Pileus Git - ~andy/linux/blob - security/selinux/hooks.c

   1 /*
   2  *  NSA Security-Enhanced Linux (SELinux) security module
   3  *
   4  *  This file contains the SELinux hook function implementations.
   5  *
   6  *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
   7  *            Chris Vance, <cvance@nai.com>
   8  *            Wayne Salamon, <wsalamon@nai.com>
   9  *            James Morris <jmorris@redhat.com>
  10  *
  11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
  13  *                                         Eric Paris <eparis@redhat.com>
  14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  15  *                          <dgoeddel@trustedcs.com>
  16  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
  17  *      Paul Moore <paul@paul-moore.com>
  18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  19  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
  20  *
  21  *      This program is free software; you can redistribute it and/or modify
  22  *      it under the terms of the GNU General Public License version 2,
  23  *      as published by the Free Software Foundation.
  24  */
  25
  26 #include <linux/init.h>
  27 #include <linux/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         } else {
1990                 /* Check for a default transition on this program. */
1991                 rc = security_transition_sid(old_tsec->sid, isec->sid,
1992                                              SECCLASS_PROCESS, NULL,
1993                                              &new_tsec->sid);
1994                 if (rc)
1995                         return rc;
1996         }
1997
1998         ad.type = LSM_AUDIT_DATA_PATH;
1999         ad.u.path = bprm->file->f_path;
2000
2001         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2002                 new_tsec->sid = old_tsec->sid;
2003
2004         if (new_tsec->sid == old_tsec->sid) {
2005                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2006                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2007                 if (rc)
2008                         return rc;
2009         } else {
2010                 /* Check permissions for the transition. */
2011                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2012                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2013                 if (rc)
2014                         return rc;
2015
2016                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2017                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2018                 if (rc)
2019                         return rc;
2020
2021                 /* Check for shared state */
2022                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2023                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2024                                           SECCLASS_PROCESS, PROCESS__SHARE,
2025                                           NULL);
2026                         if (rc)
2027                                 return -EPERM;
2028                 }
2029
2030                 /* Make sure that anyone attempting to ptrace over a task that
2031                  * changes its SID has the appropriate permit */
2032                 if (bprm->unsafe &
2033                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2034                         struct task_struct *tracer;
2035                         struct task_security_struct *sec;
2036                         u32 ptsid = 0;
2037
2038                         rcu_read_lock();
2039                         tracer = ptrace_parent(current);
2040                         if (likely(tracer != NULL)) {
2041                                 sec = __task_cred(tracer)->security;
2042                                 ptsid = sec->sid;
2043                         }
2044                         rcu_read_unlock();
2045
2046                         if (ptsid != 0) {
2047                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2048                                                   SECCLASS_PROCESS,
2049                                                   PROCESS__PTRACE, NULL);
2050                                 if (rc)
2051                                         return -EPERM;
2052                         }
2053                 }
2054
2055                 /* Clear any possibly unsafe personality bits on exec: */
2056                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2057         }
2058
2059         return 0;
2060 }
2061
2062 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2063 {
2064         const struct task_security_struct *tsec = current_security();
2065         u32 sid, osid;
2066         int atsecure = 0;
2067
2068         sid = tsec->sid;
2069         osid = tsec->osid;
2070
2071         if (osid != sid) {
2072                 /* Enable secure mode for SIDs transitions unless
2073                    the noatsecure permission is granted between
2074                    the two SIDs, i.e. ahp returns 0. */
2075                 atsecure = avc_has_perm(osid, sid,
2076                                         SECCLASS_PROCESS,
2077                                         PROCESS__NOATSECURE, NULL);
2078         }
2079
2080         return (atsecure || cap_bprm_secureexec(bprm));
2081 }
2082
2083 /* Derived from fs/exec.c:flush_old_files. */
2084 static inline void flush_unauthorized_files(const struct cred *cred,
2085                                             struct files_struct *files)
2086 {
2087         struct file *file, *devnull = NULL;
2088         struct tty_struct *tty;
2089         struct fdtable *fdt;
2090         long j = -1;
2091         int drop_tty = 0;
2092
2093         tty = get_current_tty();
2094         if (tty) {
2095                 spin_lock(&tty_files_lock);
2096                 if (!list_empty(&tty->tty_files)) {
2097                         struct tty_file_private *file_priv;
2098
2099                         /* Revalidate access to controlling tty.
2100                            Use path_has_perm on the tty path directly rather
2101                            than using file_has_perm, as this particular open
2102                            file may belong to another process and we are only
2103                            interested in the inode-based check here. */
2104                         file_priv = list_first_entry(&tty->tty_files,
2105                                                 struct tty_file_private, list);
2106                         file = file_priv->file;
2107                         if (path_has_perm(cred, &file->f_path, FILE__READ | FILE__WRITE))
2108                                 drop_tty = 1;
2109                 }
2110                 spin_unlock(&tty_files_lock);
2111                 tty_kref_put(tty);
2112         }
2113         /* Reset controlling tty. */
2114         if (drop_tty)
2115                 no_tty();
2116
2117         /* Revalidate access to inherited open files. */
2118         spin_lock(&files->file_lock);
2119         for (;;) {
2120                 unsigned long set, i;
2121                 int fd;
2122
2123                 j++;
2124                 i = j * __NFDBITS;
2125                 fdt = files_fdtable(files);
2126                 if (i >= fdt->max_fds)
2127                         break;
2128                 set = fdt->open_fds[j];
2129                 if (!set)
2130                         continue;
2131                 spin_unlock(&files->file_lock);
2132                 for ( ; set ; i++, set >>= 1) {
2133                         if (set & 1) {
2134                                 file = fget(i);
2135                                 if (!file)
2136                                         continue;
2137                                 if (file_has_perm(cred,
2138                                                   file,
2139                                                   file_to_av(file))) {
2140                                         sys_close(i);
2141                                         fd = get_unused_fd();
2142                                         if (fd != i) {
2143                                                 if (fd >= 0)
2144                                                         put_unused_fd(fd);
2145                                                 fput(file);
2146                                                 continue;
2147                                         }
2148                                         if (devnull) {
2149                                                 get_file(devnull);
2150                                         } else {
2151                                                 devnull = dentry_open(
2152                                                         dget(selinux_null),
2153                                                         mntget(selinuxfs_mount),
2154                                                         O_RDWR, cred);
2155                                                 if (IS_ERR(devnull)) {
2156                                                         devnull = NULL;
2157                                                         put_unused_fd(fd);
2158                                                         fput(file);
2159                                                         continue;
2160                                                 }
2161                                         }
2162                                         fd_install(fd, devnull);
2163                                 }
2164                                 fput(file);
2165                         }
2166                 }
2167                 spin_lock(&files->file_lock);
2168
2169         }
2170         spin_unlock(&files->file_lock);
2171 }
2172
2173 /*
2174  * Prepare a process for imminent new credential changes due to exec
2175  */
2176 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2177 {
2178         struct task_security_struct *new_tsec;
2179         struct rlimit *rlim, *initrlim;
2180         int rc, i;
2181
2182         new_tsec = bprm->cred->security;
2183         if (new_tsec->sid == new_tsec->osid)
2184                 return;
2185
2186         /* Close files for which the new task SID is not authorized. */
2187         flush_unauthorized_files(bprm->cred, current->files);
2188
2189         /* Always clear parent death signal on SID transitions. */
2190         current->pdeath_signal = 0;
2191
2192         /* Check whether the new SID can inherit resource limits from the old
2193          * SID.  If not, reset all soft limits to the lower of the current
2194          * task's hard limit and the init task's soft limit.
2195          *
2196          * Note that the setting of hard limits (even to lower them) can be
2197          * controlled by the setrlimit check.  The inclusion of the init task's
2198          * soft limit into the computation is to avoid resetting soft limits
2199          * higher than the default soft limit for cases where the default is
2200          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2201          */
2202         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2203                           PROCESS__RLIMITINH, NULL);
2204         if (rc) {
2205                 /* protect against do_prlimit() */
2206                 task_lock(current);
2207                 for (i = 0; i < RLIM_NLIMITS; i++) {
2208                         rlim = current->signal->rlim + i;
2209                         initrlim = init_task.signal->rlim + i;
2210                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2211                 }
2212                 task_unlock(current);
2213                 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2214         }
2215 }
2216
2217 /*
2218  * Clean up the process immediately after the installation of new credentials
2219  * due to exec
2220  */
2221 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2222 {
2223         const struct task_security_struct *tsec = current_security();
2224         struct itimerval itimer;
2225         u32 osid, sid;
2226         int rc, i;
2227
2228         osid = tsec->osid;
2229         sid = tsec->sid;
2230
2231         if (sid == osid)
2232                 return;
2233
2234         /* Check whether the new SID can inherit signal state from the old SID.
2235          * If not, clear itimers to avoid subsequent signal generation and
2236          * flush and unblock signals.
2237          *
2238          * This must occur _after_ the task SID has been updated so that any
2239          * kill done after the flush will be checked against the new SID.
2240          */
2241         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2242         if (rc) {
2243                 memset(&itimer, 0, sizeof itimer);
2244                 for (i = 0; i < 3; i++)
2245                         do_setitimer(i, &itimer, NULL);
2246                 spin_lock_irq(&current->sighand->siglock);
2247                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2248                         __flush_signals(current);
2249                         flush_signal_handlers(current, 1);
2250                         sigemptyset(&current->blocked);
2251                 }
2252                 spin_unlock_irq(&current->sighand->siglock);
2253         }
2254
2255         /* Wake up the parent if it is waiting so that it can recheck
2256          * wait permission to the new task SID. */
2257         read_lock(&tasklist_lock);
2258         __wake_up_parent(current, current->real_parent);
2259         read_unlock(&tasklist_lock);
2260 }
2261
2262 /* superblock security operations */
2263
2264 static int selinux_sb_alloc_security(struct super_block *sb)
2265 {
2266         return superblock_alloc_security(sb);
2267 }
2268
2269 static void selinux_sb_free_security(struct super_block *sb)
2270 {
2271         superblock_free_security(sb);
2272 }
2273
2274 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2275 {
2276         if (plen > olen)
2277                 return 0;
2278
2279         return !memcmp(prefix, option, plen);
2280 }
2281
2282 static inline int selinux_option(char *option, int len)
2283 {
2284         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2285                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2286                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2287                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2288                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2289 }
2290
2291 static inline void take_option(char **to, char *from, int *first, int len)
2292 {
2293         if (!*first) {
2294                 **to = ',';
2295                 *to += 1;
2296         } else
2297                 *first = 0;
2298         memcpy(*to, from, len);
2299         *to += len;
2300 }
2301
2302 static inline void take_selinux_option(char **to, char *from, int *first,
2303                                        int len)
2304 {
2305         int current_size = 0;
2306
2307         if (!*first) {
2308                 **to = '|';
2309                 *to += 1;
2310         } else
2311                 *first = 0;
2312
2313         while (current_size < len) {
2314                 if (*from != '"') {
2315                         **to = *from;
2316                         *to += 1;
2317                 }
2318                 from += 1;
2319                 current_size += 1;
2320         }
2321 }
2322
2323 static int selinux_sb_copy_data(char *orig, char *copy)
2324 {
2325         int fnosec, fsec, rc = 0;
2326         char *in_save, *in_curr, *in_end;
2327         char *sec_curr, *nosec_save, *nosec;
2328         int open_quote = 0;
2329
2330         in_curr = orig;
2331         sec_curr = copy;
2332
2333         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2334         if (!nosec) {
2335                 rc = -ENOMEM;
2336                 goto out;
2337         }
2338
2339         nosec_save = nosec;
2340         fnosec = fsec = 1;
2341         in_save = in_end = orig;
2342
2343         do {
2344                 if (*in_end == '"')
2345                         open_quote = !open_quote;
2346                 if ((*in_end == ',' && open_quote == 0) ||
2347                                 *in_end == '\0') {
2348                         int len = in_end - in_curr;
2349
2350                         if (selinux_option(in_curr, len))
2351                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2352                         else
2353                                 take_option(&nosec, in_curr, &fnosec, len);
2354
2355                         in_curr = in_end + 1;
2356                 }
2357         } while (*in_end++);
2358
2359         strcpy(in_save, nosec_save);
2360         free_page((unsigned long)nosec_save);
2361 out:
2362         return rc;
2363 }
2364
2365 static int selinux_sb_remount(struct super_block *sb, void *data)
2366 {
2367         int rc, i, *flags;
2368         struct security_mnt_opts opts;
2369         char *secdata, **mount_options;
2370         struct superblock_security_struct *sbsec = sb->s_security;
2371
2372         if (!(sbsec->flags & SE_SBINITIALIZED))
2373                 return 0;
2374
2375         if (!data)
2376                 return 0;
2377
2378         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2379                 return 0;
2380
2381         security_init_mnt_opts(&opts);
2382         secdata = alloc_secdata();
2383         if (!secdata)
2384                 return -ENOMEM;
2385         rc = selinux_sb_copy_data(data, secdata);
2386         if (rc)
2387                 goto out_free_secdata;
2388
2389         rc = selinux_parse_opts_str(secdata, &opts);
2390         if (rc)
2391                 goto out_free_secdata;
2392
2393         mount_options = opts.mnt_opts;
2394         flags = opts.mnt_opts_flags;
2395
2396         for (i = 0; i < opts.num_mnt_opts; i++) {
2397                 u32 sid;
2398                 size_t len;
2399
2400                 if (flags[i] == SE_SBLABELSUPP)
2401                         continue;
2402                 len = strlen(mount_options[i]);
2403                 rc = security_context_to_sid(mount_options[i], len, &sid);
2404                 if (rc) {
2405                         printk(KERN_WARNING "SELinux: security_context_to_sid"
2406                                "(%s) failed for (dev %s, type %s) errno=%d\n",
2407                                mount_options[i], sb->s_id, sb->s_type->name, rc);
2408                         goto out_free_opts;
2409                 }
2410                 rc = -EINVAL;
2411                 switch (flags[i]) {
2412                 case FSCONTEXT_MNT:
2413                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2414                                 goto out_bad_option;
2415                         break;
2416                 case CONTEXT_MNT:
2417                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2418                                 goto out_bad_option;
2419                         break;
2420                 case ROOTCONTEXT_MNT: {
2421                         struct inode_security_struct *root_isec;
2422                         root_isec = sb->s_root->d_inode->i_security;
2423
2424                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2425                                 goto out_bad_option;
2426                         break;
2427                 }
2428                 case DEFCONTEXT_MNT:
2429                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2430                                 goto out_bad_option;
2431                         break;
2432                 default:
2433                         goto out_free_opts;
2434                 }
2435         }
2436
2437         rc = 0;
2438 out_free_opts:
2439         security_free_mnt_opts(&opts);
2440 out_free_secdata:
2441         free_secdata(secdata);
2442         return rc;
2443 out_bad_option:
2444         printk(KERN_WARNING "SELinux: unable to change security options "
2445                "during remount (dev %s, type=%s)\n", sb->s_id,
2446                sb->s_type->name);
2447         goto out_free_opts;
2448 }
2449
2450 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2451 {
2452         const struct cred *cred = current_cred();
2453         struct common_audit_data ad;
2454         int rc;
2455
2456         rc = superblock_doinit(sb, data);
2457         if (rc)
2458                 return rc;
2459
2460         /* Allow all mounts performed by the kernel */
2461         if (flags & MS_KERNMOUNT)
2462                 return 0;
2463
2464         ad.type = LSM_AUDIT_DATA_DENTRY;
2465         ad.u.dentry = sb->s_root;
2466         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2467 }
2468
2469 static int selinux_sb_statfs(struct dentry *dentry)
2470 {
2471         const struct cred *cred = current_cred();
2472         struct common_audit_data ad;
2473
2474         ad.type = LSM_AUDIT_DATA_DENTRY;
2475         ad.u.dentry = dentry->d_sb->s_root;
2476         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2477 }
2478
2479 static int selinux_mount(char *dev_name,
2480                          struct path *path,
2481                          char *type,
2482                          unsigned long flags,
2483                          void *data)
2484 {
2485         const struct cred *cred = current_cred();
2486
2487         if (flags & MS_REMOUNT)
2488                 return superblock_has_perm(cred, path->dentry->d_sb,
2489                                            FILESYSTEM__REMOUNT, NULL);
2490         else
2491                 return path_has_perm(cred, path, FILE__MOUNTON);
2492 }
2493
2494 static int selinux_umount(struct vfsmount *mnt, int flags)
2495 {
2496         const struct cred *cred = current_cred();
2497
2498         return superblock_has_perm(cred, mnt->mnt_sb,
2499                                    FILESYSTEM__UNMOUNT, NULL);
2500 }
2501
2502 /* inode security operations */
2503
2504 static int selinux_inode_alloc_security(struct inode *inode)
2505 {
2506         return inode_alloc_security(inode);
2507 }
2508
2509 static void selinux_inode_free_security(struct inode *inode)
2510 {
2511         inode_free_security(inode);
2512 }
2513
2514 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2515                                        const struct qstr *qstr, char **name,
2516                                        void **value, size_t *len)
2517 {
2518         const struct task_security_struct *tsec = current_security();
2519         struct inode_security_struct *dsec;
2520         struct superblock_security_struct *sbsec;
2521         u32 sid, newsid, clen;
2522         int rc;
2523         char *namep = NULL, *context;
2524
2525         dsec = dir->i_security;
2526         sbsec = dir->i_sb->s_security;
2527
2528         sid = tsec->sid;
2529         newsid = tsec->create_sid;
2530
2531         if ((sbsec->flags & SE_SBINITIALIZED) &&
2532             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2533                 newsid = sbsec->mntpoint_sid;
2534         else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2535                 rc = security_transition_sid(sid, dsec->sid,
2536                                              inode_mode_to_security_class(inode->i_mode),
2537                                              qstr, &newsid);
2538                 if (rc) {
2539                         printk(KERN_WARNING "%s:  "
2540                                "security_transition_sid failed, rc=%d (dev=%s "
2541                                "ino=%ld)\n",
2542                                __func__,
2543                                -rc, inode->i_sb->s_id, inode->i_ino);
2544                         return rc;
2545                 }
2546         }
2547
2548         /* Possibly defer initialization to selinux_complete_init. */
2549         if (sbsec->flags & SE_SBINITIALIZED) {
2550                 struct inode_security_struct *isec = inode->i_security;
2551                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2552                 isec->sid = newsid;
2553                 isec->initialized = 1;
2554         }
2555
2556         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2557                 return -EOPNOTSUPP;
2558
2559         if (name) {
2560                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2561                 if (!namep)
2562                         return -ENOMEM;
2563                 *name = namep;
2564         }
2565
2566         if (value && len) {
2567                 rc = security_sid_to_context_force(newsid, &context, &clen);
2568                 if (rc) {
2569                         kfree(namep);
2570                         return rc;
2571                 }
2572                 *value = context;
2573                 *len = clen;
2574         }
2575
2576         return 0;
2577 }
2578
2579 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2580 {
2581         return may_create(dir, dentry, SECCLASS_FILE);
2582 }
2583
2584 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2585 {
2586         return may_link(dir, old_dentry, MAY_LINK);
2587 }
2588
2589 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2590 {
2591         return may_link(dir, dentry, MAY_UNLINK);
2592 }
2593
2594 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2595 {
2596         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2597 }
2598
2599 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2600 {
2601         return may_create(dir, dentry, SECCLASS_DIR);
2602 }
2603
2604 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2605 {
2606         return may_link(dir, dentry, MAY_RMDIR);
2607 }
2608
2609 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2610 {
2611         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2612 }
2613
2614 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2615                                 struct inode *new_inode, struct dentry *new_dentry)
2616 {
2617         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2618 }
2619
2620 static int selinux_inode_readlink(struct dentry *dentry)
2621 {
2622         const struct cred *cred = current_cred();
2623
2624         return dentry_has_perm(cred, dentry, FILE__READ);
2625 }
2626
2627 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2628 {
2629         const struct cred *cred = current_cred();
2630
2631         return dentry_has_perm(cred, dentry, FILE__READ);
2632 }
2633
2634 static noinline int audit_inode_permission(struct inode *inode,
2635                                            u32 perms, u32 audited, u32 denied,
2636                                            unsigned flags)
2637 {
2638         struct common_audit_data ad;
2639         struct inode_security_struct *isec = inode->i_security;
2640         int rc;
2641
2642         ad.type = LSM_AUDIT_DATA_INODE;
2643         ad.u.inode = inode;
2644
2645         rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2646                             audited, denied, &ad, flags);
2647         if (rc)
2648                 return rc;
2649         return 0;
2650 }
2651
2652 static int selinux_inode_permission(struct inode *inode, int mask)
2653 {
2654         const struct cred *cred = current_cred();
2655         u32 perms;
2656         bool from_access;
2657         unsigned flags = mask & MAY_NOT_BLOCK;
2658         struct inode_security_struct *isec;
2659         u32 sid;
2660         struct av_decision avd;
2661         int rc, rc2;
2662         u32 audited, denied;
2663
2664         from_access = mask & MAY_ACCESS;
2665         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2666
2667         /* No permission to check.  Existence test. */
2668         if (!mask)
2669                 return 0;
2670
2671         validate_creds(cred);
2672
2673         if (unlikely(IS_PRIVATE(inode)))
2674                 return 0;
2675
2676         perms = file_mask_to_av(inode->i_mode, mask);
2677
2678         sid = cred_sid(cred);
2679         isec = inode->i_security;
2680
2681         rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
2682         audited = avc_audit_required(perms, &avd, rc,
2683                                      from_access ? FILE__AUDIT_ACCESS : 0,
2684                                      &denied);
2685         if (likely(!audited))
2686                 return rc;
2687
2688         rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2689         if (rc2)
2690                 return rc2;
2691         return rc;
2692 }
2693
2694 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2695 {
2696         const struct cred *cred = current_cred();
2697         unsigned int ia_valid = iattr->ia_valid;
2698         __u32 av = FILE__WRITE;
2699
2700         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2701         if (ia_valid & ATTR_FORCE) {
2702                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2703                               ATTR_FORCE);
2704                 if (!ia_valid)
2705                         return 0;
2706         }
2707
2708         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2709                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2710                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2711
2712         if (ia_valid & ATTR_SIZE)
2713                 av |= FILE__OPEN;
2714
2715         return dentry_has_perm(cred, dentry, av);
2716 }
2717
2718 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2719 {
2720         const struct cred *cred = current_cred();
2721         struct path path;
2722
2723         path.dentry = dentry;
2724         path.mnt = mnt;
2725
2726         return path_has_perm(cred, &path, FILE__GETATTR);
2727 }
2728
2729 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2730 {
2731         const struct cred *cred = current_cred();
2732
2733         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2734                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2735                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2736                         if (!capable(CAP_SETFCAP))
2737                                 return -EPERM;
2738                 } else if (!capable(CAP_SYS_ADMIN)) {
2739                         /* A different attribute in the security namespace.
2740                            Restrict to administrator. */
2741                         return -EPERM;
2742                 }
2743         }
2744
2745         /* Not an attribute we recognize, so just check the
2746            ordinary setattr permission. */
2747         return dentry_has_perm(cred, dentry, FILE__SETATTR);
2748 }
2749
2750 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2751                                   const void *value, size_t size, int flags)
2752 {
2753         struct inode *inode = dentry->d_inode;
2754         struct inode_security_struct *isec = inode->i_security;
2755         struct superblock_security_struct *sbsec;
2756         struct common_audit_data ad;
2757         u32 newsid, sid = current_sid();
2758         int rc = 0;
2759
2760         if (strcmp(name, XATTR_NAME_SELINUX))
2761                 return selinux_inode_setotherxattr(dentry, name);
2762
2763         sbsec = inode->i_sb->s_security;
2764         if (!(sbsec->flags & SE_SBLABELSUPP))
2765                 return -EOPNOTSUPP;
2766
2767         if (!inode_owner_or_capable(inode))
2768                 return -EPERM;
2769
2770         ad.type = LSM_AUDIT_DATA_DENTRY;
2771         ad.u.dentry = dentry;
2772
2773         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2774                           FILE__RELABELFROM, &ad);
2775         if (rc)
2776                 return rc;
2777
2778         rc = security_context_to_sid(value, size, &newsid);
2779         if (rc == -EINVAL) {
2780                 if (!capable(CAP_MAC_ADMIN)) {
2781                         struct audit_buffer *ab;
2782                         size_t audit_size;
2783                         const char *str;
2784
2785                         /* We strip a nul only if it is at the end, otherwise the
2786                          * context contains a nul and we should audit that */
2787                         str = value;
2788                         if (str[size - 1] == '\0')
2789                                 audit_size = size - 1;
2790                         else
2791                                 audit_size = size;
2792                         ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
2793                         audit_log_format(ab, "op=setxattr invalid_context=");
2794                         audit_log_n_untrustedstring(ab, value, audit_size);
2795                         audit_log_end(ab);
2796
2797                         return rc;
2798                 }
2799                 rc = security_context_to_sid_force(value, size, &newsid);
2800         }
2801         if (rc)
2802                 return rc;
2803
2804         rc = avc_has_perm(sid, newsid, isec->sclass,
2805                           FILE__RELABELTO, &ad);
2806         if (rc)
2807                 return rc;
2808
2809         rc = security_validate_transition(isec->sid, newsid, sid,
2810                                           isec->sclass);
2811         if (rc)
2812                 return rc;
2813
2814         return avc_has_perm(newsid,
2815                             sbsec->sid,
2816                             SECCLASS_FILESYSTEM,
2817                             FILESYSTEM__ASSOCIATE,
2818                             &ad);
2819 }
2820
2821 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2822                                         const void *value, size_t size,
2823                                         int flags)
2824 {
2825         struct inode *inode = dentry->d_inode;
2826         struct inode_security_struct *isec = inode->i_security;
2827         u32 newsid;
2828         int rc;
2829
2830         if (strcmp(name, XATTR_NAME_SELINUX)) {
2831                 /* Not an attribute we recognize, so nothing to do. */
2832                 return;
2833         }
2834
2835         rc = security_context_to_sid_force(value, size, &newsid);
2836         if (rc) {
2837                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2838                        "for (%s, %lu), rc=%d\n",
2839                        inode->i_sb->s_id, inode->i_ino, -rc);
2840                 return;
2841         }
2842
2843         isec->sid = newsid;
2844         return;
2845 }
2846
2847 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2848 {
2849         const struct cred *cred = current_cred();
2850
2851         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2852 }
2853
2854 static int selinux_inode_listxattr(struct dentry *dentry)
2855 {
2856         const struct cred *cred = current_cred();
2857
2858         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2859 }
2860
2861 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2862 {
2863         if (strcmp(name, XATTR_NAME_SELINUX))
2864                 return selinux_inode_setotherxattr(dentry, name);
2865
2866         /* No one is allowed to remove a SELinux security label.
2867            You can change the label, but all data must be labeled. */
2868         return -EACCES;
2869 }
2870
2871 /*
2872  * Copy the inode security context value to the user.
2873  *
2874  * Permission check is handled by selinux_inode_getxattr hook.
2875  */
2876 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2877 {
2878         u32 size;
2879         int error;
2880         char *context = NULL;
2881         struct inode_security_struct *isec = inode->i_security;
2882
2883         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2884                 return -EOPNOTSUPP;
2885
2886         /*
2887          * If the caller has CAP_MAC_ADMIN, then get the raw context
2888          * value even if it is not defined by current policy; otherwise,
2889          * use the in-core value under current policy.
2890          * Use the non-auditing forms of the permission checks since
2891          * getxattr may be called by unprivileged processes commonly
2892          * and lack of permission just means that we fall back to the
2893          * in-core context value, not a denial.
2894          */
2895         error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
2896                                 SECURITY_CAP_NOAUDIT);
2897         if (!error)
2898                 error = security_sid_to_context_force(isec->sid, &context,
2899                                                       &size);
2900         else
2901                 error = security_sid_to_context(isec->sid, &context, &size);
2902         if (error)
2903                 return error;
2904         error = size;
2905         if (alloc) {
2906                 *buffer = context;
2907                 goto out_nofree;
2908         }
2909         kfree(context);
2910 out_nofree:
2911         return error;
2912 }
2913
2914 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2915                                      const void *value, size_t size, int flags)
2916 {
2917         struct inode_security_struct *isec = inode->i_security;
2918         u32 newsid;
2919         int rc;
2920
2921         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2922                 return -EOPNOTSUPP;
2923
2924         if (!value || !size)
2925                 return -EACCES;
2926
2927         rc = security_context_to_sid((void *)value, size, &newsid);
2928         if (rc)
2929                 return rc;
2930
2931         isec->sid = newsid;
2932         isec->initialized = 1;
2933         return 0;
2934 }
2935
2936 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2937 {
2938         const int len = sizeof(XATTR_NAME_SELINUX);
2939         if (buffer && len <= buffer_size)
2940                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2941         return len;
2942 }
2943
2944 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2945 {
2946         struct inode_security_struct *isec = inode->i_security;
2947         *secid = isec->sid;
2948 }
2949
2950 /* file security operations */
2951
2952 static int selinux_revalidate_file_permission(struct file *file, int mask)
2953 {
2954         const struct cred *cred = current_cred();
2955         struct inode *inode = file->f_path.dentry->d_inode;
2956
2957         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2958         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2959                 mask |= MAY_APPEND;
2960
2961         return file_has_perm(cred, file,
2962                              file_mask_to_av(inode->i_mode, mask));
2963 }
2964
2965 static int selinux_file_permission(struct file *file, int mask)
2966 {
2967         struct inode *inode = file->f_path.dentry->d_inode;
2968         struct file_security_struct *fsec = file->f_security;
2969         struct inode_security_struct *isec = inode->i_security;
2970         u32 sid = current_sid();
2971
2972         if (!mask)
2973                 /* No permission to check.  Existence test. */
2974                 return 0;
2975
2976         if (sid == fsec->sid && fsec->isid == isec->sid &&
2977             fsec->pseqno == avc_policy_seqno())
2978                 /* No change since file_open check. */
2979                 return 0;
2980
2981         return selinux_revalidate_file_permission(file, mask);
2982 }
2983
2984 static int selinux_file_alloc_security(struct file *file)
2985 {
2986         return file_alloc_security(file);
2987 }
2988
2989 static void selinux_file_free_security(struct file *file)
2990 {
2991         file_free_security(file);
2992 }
2993
2994 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2995                               unsigned long arg)
2996 {
2997         const struct cred *cred = current_cred();
2998         int error = 0;
2999
3000         switch (cmd) {
3001         case FIONREAD:
3002         /* fall through */
3003         case FIBMAP:
3004         /* fall through */
3005         case FIGETBSZ:
3006         /* fall through */
3007         case FS_IOC_GETFLAGS:
3008         /* fall through */
3009         case FS_IOC_GETVERSION:
3010                 error = file_has_perm(cred, file, FILE__GETATTR);
3011                 break;
3012
3013         case FS_IOC_SETFLAGS:
3014         /* fall through */
3015         case FS_IOC_SETVERSION:
3016                 error = file_has_perm(cred, file, FILE__SETATTR);
3017                 break;
3018
3019         /* sys_ioctl() checks */
3020         case FIONBIO:
3021         /* fall through */
3022         case FIOASYNC:
3023                 error = file_has_perm(cred, file, 0);
3024                 break;
3025
3026         case KDSKBENT:
3027         case KDSKBSENT:
3028                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3029                                             SECURITY_CAP_AUDIT);
3030                 break;
3031
3032         /* default case assumes that the command will go
3033          * to the file's ioctl() function.
3034          */
3035         default:
3036                 error = file_has_perm(cred, file, FILE__IOCTL);
3037         }
3038         return error;
3039 }
3040
3041 static int default_noexec;
3042
3043 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3044 {
3045         const struct cred *cred = current_cred();
3046         int rc = 0;
3047
3048         if (default_noexec &&
3049             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3050                 /*
3051                  * We are making executable an anonymous mapping or a
3052                  * private file mapping that will also be writable.
3053                  * This has an additional check.
3054                  */
3055                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3056                 if (rc)
3057                         goto error;
3058         }
3059
3060         if (file) {
3061                 /* read access is always possible with a mapping */
3062                 u32 av = FILE__READ;
3063
3064                 /* write access only matters if the mapping is shared */
3065                 if (shared && (prot & PROT_WRITE))
3066                         av |= FILE__WRITE;
3067
3068                 if (prot & PROT_EXEC)
3069                         av |= FILE__EXECUTE;
3070
3071                 return file_has_perm(cred, file, av);
3072         }
3073
3074 error:
3075         return rc;
3076 }
3077
3078 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3079                              unsigned long prot, unsigned long flags,
3080                              unsigned long addr, unsigned long addr_only)
3081 {
3082         int rc = 0;
3083         u32 sid = current_sid();
3084
3085         /*
3086          * notice that we are intentionally putting the SELinux check before
3087          * the secondary cap_file_mmap check.  This is such a likely attempt
3088          * at bad behaviour/exploit that we always want to get the AVC, even
3089          * if DAC would have also denied the operation.
3090          */
3091         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3092                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3093                                   MEMPROTECT__MMAP_ZERO, NULL);
3094                 if (rc)
3095                         return rc;
3096         }
3097
3098         /* do DAC check on address space usage */
3099         rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3100         if (rc || addr_only)
3101                 return rc;
3102
3103         if (selinux_checkreqprot)
3104                 prot = reqprot;
3105
3106         return file_map_prot_check(file, prot,
3107                                    (flags & MAP_TYPE) == MAP_SHARED);
3108 }
3109
3110 static int selinux_file_mprotect(struct vm_area_struct *vma,
3111                                  unsigned long reqprot,
3112                                  unsigned long prot)
3113 {
3114         const struct cred *cred = current_cred();
3115
3116         if (selinux_checkreqprot)
3117                 prot = reqprot;
3118
3119         if (default_noexec &&
3120             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3121                 int rc = 0;
3122                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3123                     vma->vm_end <= vma->vm_mm->brk) {
3124                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3125                 } else if (!vma->vm_file &&
3126                            vma->vm_start <= vma->vm_mm->start_stack &&
3127                            vma->vm_end >= vma->vm_mm->start_stack) {
3128                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3129                 } else if (vma->vm_file && vma->anon_vma) {
3130                         /*
3131                          * We are making executable a file mapping that has
3132                          * had some COW done. Since pages might have been
3133                          * written, check ability to execute the possibly
3134                          * modified content.  This typically should only
3135                          * occur for text relocations.
3136                          */
3137                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3138                 }
3139                 if (rc)
3140                         return rc;
3141         }
3142
3143         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3144 }
3145
3146 static int selinux_file_lock(struct file *file, unsigned int cmd)
3147 {
3148         const struct cred *cred = current_cred();
3149
3150         return file_has_perm(cred, file, FILE__LOCK);
3151 }
3152
3153 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3154                               unsigned long arg)
3155 {
3156         const struct cred *cred = current_cred();
3157         int err = 0;
3158
3159         switch (cmd) {
3160         case F_SETFL:
3161                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3162                         err = -EINVAL;
3163                         break;
3164                 }
3165
3166                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3167                         err = file_has_perm(cred, file, FILE__WRITE);
3168                         break;
3169                 }
3170                 /* fall through */
3171         case F_SETOWN:
3172         case F_SETSIG:
3173         case F_GETFL:
3174         case F_GETOWN:
3175         case F_GETSIG:
3176                 /* Just check FD__USE permission */
3177                 err = file_has_perm(cred, file, 0);
3178                 break;
3179         case F_GETLK:
3180         case F_SETLK:
3181         case F_SETLKW:
3182 #if BITS_PER_LONG == 32
3183         case F_GETLK64:
3184         case F_SETLK64:
3185         case F_SETLKW64:
3186 #endif
3187                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3188                         err = -EINVAL;
3189                         break;
3190                 }
3191                 err = file_has_perm(cred, file, FILE__LOCK);
3192                 break;
3193         }
3194
3195         return err;
3196 }
3197
3198 static int selinux_file_set_fowner(struct file *file)
3199 {
3200         struct file_security_struct *fsec;
3201
3202         fsec = file->f_security;
3203         fsec->fown_sid = current_sid();
3204
3205         return 0;
3206 }
3207
3208 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3209                                        struct fown_struct *fown, int signum)
3210 {
3211         struct file *file;
3212         u32 sid = task_sid(tsk);
3213         u32 perm;
3214         struct file_security_struct *fsec;
3215
3216         /* struct fown_struct is never outside the context of a struct file */
3217         file = container_of(fown, struct file, f_owner);
3218
3219         fsec = file->f_security;
3220
3221         if (!signum)
3222                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3223         else
3224                 perm = signal_to_av(signum);
3225
3226         return avc_has_perm(fsec->fown_sid, sid,
3227                             SECCLASS_PROCESS, perm, NULL);
3228 }
3229
3230 static int selinux_file_receive(struct file *file)
3231 {
3232         const struct cred *cred = current_cred();
3233
3234         return file_has_perm(cred, file, file_to_av(file));
3235 }
3236
3237 static int selinux_file_open(struct file *file, const struct cred *cred)
3238 {
3239         struct file_security_struct *fsec;
3240         struct inode_security_struct *isec;
3241
3242         fsec = file->f_security;
3243         isec = file->f_path.dentry->d_inode->i_security;
3244         /*
3245          * Save inode label and policy sequence number
3246          * at open-time so that selinux_file_permission
3247          * can determine whether revalidation is necessary.
3248          * Task label is already saved in the file security
3249          * struct as its SID.
3250          */
3251         fsec->isid = isec->sid;
3252         fsec->pseqno = avc_policy_seqno();
3253         /*
3254          * Since the inode label or policy seqno may have changed
3255          * between the selinux_inode_permission check and the saving
3256          * of state above, recheck that access is still permitted.
3257          * Otherwise, access might never be revalidated against the
3258          * new inode label or new policy.
3259          * This check is not redundant - do not remove.
3260          */
3261         return path_has_perm(cred, &file->f_path, open_file_to_av(file));
3262 }
3263
3264 /* task security operations */
3265
3266 static int selinux_task_create(unsigned long clone_flags)
3267 {
3268         return current_has_perm(current, PROCESS__FORK);
3269 }
3270
3271 /*
3272  * allocate the SELinux part of blank credentials
3273  */
3274 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3275 {
3276         struct task_security_struct *tsec;
3277
3278         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3279         if (!tsec)
3280                 return -ENOMEM;
3281
3282         cred->security = tsec;
3283         return 0;
3284 }
3285
3286 /*
3287  * detach and free the LSM part of a set of credentials
3288  */
3289 static void selinux_cred_free(struct cred *cred)
3290 {
3291         struct task_security_struct *tsec = cred->security;
3292
3293         /*
3294          * cred->security == NULL if security_cred_alloc_blank() or
3295          * security_prepare_creds() returned an error.
3296          */
3297         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3298         cred->security = (void *) 0x7UL;
3299         kfree(tsec);
3300 }
3301
3302 /*
3303  * prepare a new set of credentials for modification
3304  */
3305 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3306                                 gfp_t gfp)
3307 {
3308         const struct task_security_struct *old_tsec;
3309         struct task_security_struct *tsec;
3310
3311         old_tsec = old->security;
3312
3313         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3314         if (!tsec)
3315                 return -ENOMEM;
3316
3317         new->security = tsec;
3318         return 0;
3319 }
3320
3321 /*
3322  * transfer the SELinux data to a blank set of creds
3323  */
3324 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3325 {
3326         const struct task_security_struct *old_tsec = old->security;
3327         struct task_security_struct *tsec = new->security;
3328
3329         *tsec = *old_tsec;
3330 }
3331
3332 /*
3333  * set the security data for a kernel service
3334  * - all the creation contexts are set to unlabelled
3335  */
3336 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3337 {
3338         struct task_security_struct *tsec = new->security;
3339         u32 sid = current_sid();
3340         int ret;
3341
3342         ret = avc_has_perm(sid, secid,
3343                            SECCLASS_KERNEL_SERVICE,
3344                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3345                            NULL);
3346         if (ret == 0) {
3347                 tsec->sid = secid;
3348                 tsec->create_sid = 0;
3349                 tsec->keycreate_sid = 0;
3350                 tsec->sockcreate_sid = 0;
3351         }
3352         return ret;
3353 }
3354
3355 /*
3356  * set the file creation context in a security record to the same as the
3357  * objective context of the specified inode
3358  */
3359 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3360 {
3361         struct inode_security_struct *isec = inode->i_security;
3362         struct task_security_struct *tsec = new->security;
3363         u32 sid = current_sid();
3364         int ret;
3365
3366         ret = avc_has_perm(sid, isec->sid,
3367                            SECCLASS_KERNEL_SERVICE,
3368                            KERNEL_SERVICE__CREATE_FILES_AS,
3369                            NULL);
3370
3371         if (ret == 0)
3372                 tsec->create_sid = isec->sid;
3373         return ret;
3374 }
3375
3376 static int selinux_kernel_module_request(char *kmod_name)
3377 {
3378         u32 sid;
3379         struct common_audit_data ad;
3380
3381         sid = task_sid(current);
3382
3383         ad.type = LSM_AUDIT_DATA_KMOD;
3384         ad.u.kmod_name = kmod_name;
3385
3386         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3387                             SYSTEM__MODULE_REQUEST, &ad);
3388 }
3389
3390 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3391 {
3392         return current_has_perm(p, PROCESS__SETPGID);
3393 }
3394
3395 static int selinux_task_getpgid(struct task_struct *p)
3396 {
3397         return current_has_perm(p, PROCESS__GETPGID);
3398 }
3399
3400 static int selinux_task_getsid(struct task_struct *p)
3401 {
3402         return current_has_perm(p, PROCESS__GETSESSION);
3403 }
3404
3405 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3406 {
3407         *secid = task_sid(p);
3408 }
3409
3410 static int selinux_task_setnice(struct task_struct *p, int nice)
3411 {
3412         int rc;
3413
3414         rc = cap_task_setnice(p, nice);
3415         if (rc)
3416                 return rc;
3417
3418         return current_has_perm(p, PROCESS__SETSCHED);
3419 }
3420
3421 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3422 {
3423         int rc;
3424
3425         rc = cap_task_setioprio(p, ioprio);
3426         if (rc)
3427                 return rc;
3428
3429         return current_has_perm(p, PROCESS__SETSCHED);
3430 }
3431
3432 static int selinux_task_getioprio(struct task_struct *p)
3433 {
3434         return current_has_perm(p, PROCESS__GETSCHED);
3435 }
3436
3437 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3438                 struct rlimit *new_rlim)
3439 {
3440         struct rlimit *old_rlim = p->signal->rlim + resource;
3441
3442         /* Control the ability to change the hard limit (whether
3443            lowering or raising it), so that the hard limit can
3444            later be used as a safe reset point for the soft limit
3445            upon context transitions.  See selinux_bprm_committing_creds. */
3446         if (old_rlim->rlim_max != new_rlim->rlim_max)
3447                 return current_has_perm(p, PROCESS__SETRLIMIT);
3448
3449         return 0;
3450 }
3451
3452 static int selinux_task_setscheduler(struct task_struct *p)
3453 {
3454         int rc;
3455
3456         rc = cap_task_setscheduler(p);
3457         if (rc)
3458                 return rc;
3459
3460         return current_has_perm(p, PROCESS__SETSCHED);
3461 }
3462
3463 static int selinux_task_getscheduler(struct task_struct *p)
3464 {
3465         return current_has_perm(p, PROCESS__GETSCHED);
3466 }
3467
3468 static int selinux_task_movememory(struct task_struct *p)
3469 {
3470         return current_has_perm(p, PROCESS__SETSCHED);
3471 }
3472
3473 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3474                                 int sig, u32 secid)
3475 {
3476         u32 perm;
3477         int rc;
3478
3479         if (!sig)
3480                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3481         else
3482                 perm = signal_to_av(sig);
3483         if (secid)
3484                 rc = avc_has_perm(secid, task_sid(p),
3485                                   SECCLASS_PROCESS, perm, NULL);
3486         else
3487                 rc = current_has_perm(p, perm);
3488         return rc;
3489 }
3490
3491 static int selinux_task_wait(struct task_struct *p)
3492 {
3493         return task_has_perm(p, current, PROCESS__SIGCHLD);
3494 }
3495
3496 static void selinux_task_to_inode(struct task_struct *p,
3497                                   struct inode *inode)
3498 {
3499         struct inode_security_struct *isec = inode->i_security;
3500         u32 sid = task_sid(p);
3501
3502         isec->sid = sid;
3503         isec->initialized = 1;
3504 }
3505
3506 /* Returns error only if unable to parse addresses */
3507 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3508                         struct common_audit_data *ad, u8 *proto)
3509 {
3510         int offset, ihlen, ret = -EINVAL;
3511         struct iphdr _iph, *ih;
3512
3513         offset = skb_network_offset(skb);
3514         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3515         if (ih == NULL)
3516                 goto out;
3517
3518         ihlen = ih->ihl * 4;
3519         if (ihlen < sizeof(_iph))
3520                 goto out;
3521
3522         ad->u.net->v4info.saddr = ih->saddr;
3523         ad->u.net->v4info.daddr = ih->daddr;
3524         ret = 0;
3525
3526         if (proto)
3527                 *proto = ih->protocol;
3528
3529         switch (ih->protocol) {
3530         case IPPROTO_TCP: {
3531                 struct tcphdr _tcph, *th;
3532
3533                 if (ntohs(ih->frag_off) & IP_OFFSET)
3534                         break;
3535
3536                 offset += ihlen;
3537                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3538                 if (th == NULL)
3539                         break;
3540
3541                 ad->u.net->sport = th->source;
3542                 ad->u.net->dport = th->dest;
3543                 break;
3544         }
3545
3546         case IPPROTO_UDP: {
3547                 struct udphdr _udph, *uh;
3548
3549                 if (ntohs(ih->frag_off) & IP_OFFSET)
3550                         break;
3551
3552                 offset += ihlen;
3553                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3554                 if (uh == NULL)
3555                         break;
3556
3557                 ad->u.net->sport = uh->source;
3558                 ad->u.net->dport = uh->dest;
3559                 break;
3560         }
3561
3562         case IPPROTO_DCCP: {
3563                 struct dccp_hdr _dccph, *dh;
3564
3565                 if (ntohs(ih->frag_off) & IP_OFFSET)
3566                         break;
3567
3568                 offset += ihlen;
3569                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3570                 if (dh == NULL)
3571                         break;
3572
3573                 ad->u.net->sport = dh->dccph_sport;
3574                 ad->u.net->dport = dh->dccph_dport;
3575                 break;
3576         }
3577
3578         default:
3579                 break;
3580         }
3581 out:
3582         return ret;
3583 }
3584
3585 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3586
3587 /* Returns error only if unable to parse addresses */
3588 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3589                         struct common_audit_data *ad, u8 *proto)
3590 {
3591         u8 nexthdr;
3592         int ret = -EINVAL, offset;
3593         struct ipv6hdr _ipv6h, *ip6;
3594         __be16 frag_off;
3595
3596         offset = skb_network_offset(skb);
3597         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3598         if (ip6 == NULL)
3599                 goto out;
3600
3601         ad->u.net->v6info.saddr = ip6->saddr;
3602         ad->u.net->v6info.daddr = ip6->daddr;
3603         ret = 0;
3604
3605         nexthdr = ip6->nexthdr;
3606         offset += sizeof(_ipv6h);
3607         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3608         if (offset < 0)
3609                 goto out;
3610
3611         if (proto)
3612                 *proto = nexthdr;
3613
3614         switch (nexthdr) {
3615         case IPPROTO_TCP: {
3616                 struct tcphdr _tcph, *th;
3617
3618                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3619                 if (th == NULL)
3620                         break;
3621
3622                 ad->u.net->sport = th->source;
3623                 ad->u.net->dport = th->dest;
3624                 break;
3625         }
3626
3627         case IPPROTO_UDP: {
3628                 struct udphdr _udph, *uh;
3629
3630                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3631                 if (uh == NULL)
3632                         break;
3633
3634                 ad->u.net->sport = uh->source;
3635                 ad->u.net->dport = uh->dest;
3636                 break;
3637         }
3638
3639         case IPPROTO_DCCP: {
3640                 struct dccp_hdr _dccph, *dh;
3641
3642                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3643                 if (dh == NULL)
3644                         break;
3645
3646                 ad->u.net->sport = dh->dccph_sport;
3647                 ad->u.net->dport = dh->dccph_dport;
3648                 break;
3649         }
3650
3651         /* includes fragments */
3652         default:
3653                 break;
3654         }
3655 out:
3656         return ret;
3657 }
3658
3659 #endif /* IPV6 */
3660
3661 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3662                              char **_addrp, int src, u8 *proto)
3663 {
3664         char *addrp;
3665         int ret;
3666
3667         switch (ad->u.net->family) {
3668         case PF_INET:
3669                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3670                 if (ret)
3671                         goto parse_error;
3672                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
3673                                        &ad->u.net->v4info.daddr);
3674                 goto okay;
3675
3676 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3677         case PF_INET6:
3678                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3679                 if (ret)
3680                         goto parse_error;
3681                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
3682                                        &ad->u.net->v6info.daddr);
3683                 goto okay;
3684 #endif  /* IPV6 */
3685         default:
3686                 addrp = NULL;
3687                 goto okay;
3688         }
3689
3690 parse_error:
3691         printk(KERN_WARNING
3692                "SELinux: failure in selinux_parse_skb(),"
3693                " unable to parse packet\n");
3694         return ret;
3695
3696 okay:
3697         if (_addrp)
3698                 *_addrp = addrp;
3699         return 0;
3700 }
3701
3702 /**
3703  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3704  * @skb: the packet
3705  * @family: protocol family
3706  * @sid: the packet's peer label SID
3707  *
3708  * Description:
3709  * Check the various different forms of network peer labeling and determine
3710  * the peer label/SID for the packet; most of the magic actually occurs in
3711  * the security server function security_net_peersid_cmp().  The function
3712  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3713  * or -EACCES if @sid is invalid due to inconsistencies with the different
3714  * peer labels.
3715  *
3716  */
3717 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3718 {
3719         int err;
3720         u32 xfrm_sid;
3721         u32 nlbl_sid;
3722         u32 nlbl_type;
3723
3724         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3725         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3726
3727         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3728         if (unlikely(err)) {
3729                 printk(KERN_WARNING
3730                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3731                        " unable to determine packet's peer label\n");
3732                 return -EACCES;
3733         }
3734
3735         return 0;
3736 }
3737
3738 /* socket security operations */
3739
3740 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3741                                  u16 secclass, u32 *socksid)
3742 {
3743         if (tsec->sockcreate_sid > SECSID_NULL) {
3744                 *socksid = tsec->sockcreate_sid;
3745                 return 0;
3746         }
3747
3748         return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3749                                        socksid);
3750 }
3751
3752 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3753 {
3754         struct sk_security_struct *sksec = sk->sk_security;
3755         struct common_audit_data ad;
3756         struct lsm_network_audit net = {0,};
3757         u32 tsid = task_sid(task);
3758
3759         if (sksec->sid == SECINITSID_KERNEL)
3760                 return 0;
3761
3762         ad.type = LSM_AUDIT_DATA_NET;
3763         ad.u.net = &net;
3764         ad.u.net->sk = sk;
3765
3766         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3767 }
3768
3769 static int selinux_socket_create(int family, int type,
3770                                  int protocol, int kern)
3771 {
3772         const struct task_security_struct *tsec = current_security();
3773         u32 newsid;
3774         u16 secclass;
3775         int rc;
3776
3777         if (kern)
3778                 return 0;
3779
3780         secclass = socket_type_to_security_class(family, type, protocol);
3781         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3782         if (rc)
3783                 return rc;
3784
3785         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3786 }
3787
3788 static int selinux_socket_post_create(struct socket *sock, int family,
3789                                       int type, int protocol, int kern)
3790 {
3791         const struct task_security_struct *tsec = current_security();
3792         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3793         struct sk_security_struct *sksec;
3794         int err = 0;
3795
3796         isec->sclass = socket_type_to_security_class(family, type, protocol);
3797
3798         if (kern)
3799                 isec->sid = SECINITSID_KERNEL;
3800         else {
3801                 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3802                 if (err)
3803                         return err;
3804         }
3805
3806         isec->initialized = 1;
3807
3808         if (sock->sk) {
3809                 sksec = sock->sk->sk_security;
3810                 sksec->sid = isec->sid;
3811                 sksec->sclass = isec->sclass;
3812                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3813         }
3814
3815         return err;
3816 }
3817
3818 /* Range of port numbers used to automatically bind.
3819    Need to determine whether we should perform a name_bind
3820    permission check between the socket and the port number. */
3821
3822 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3823 {
3824         struct sock *sk = sock->sk;
3825         u16 family;
3826         int err;
3827
3828         err = sock_has_perm(current, sk, SOCKET__BIND);
3829         if (err)
3830                 goto out;
3831
3832         /*
3833          * If PF_INET or PF_INET6, check name_bind permission for the port.
3834          * Multiple address binding for SCTP is not supported yet: we just
3835          * check the first address now.
3836          */
3837         family = sk->sk_family;
3838         if (family == PF_INET || family == PF_INET6) {
3839                 char *addrp;
3840                 struct sk_security_struct *sksec = sk->sk_security;
3841                 struct common_audit_data ad;
3842                 struct lsm_network_audit net = {0,};
3843                 struct sockaddr_in *addr4 = NULL;
3844                 struct sockaddr_in6 *addr6 = NULL;
3845                 unsigned short snum;
3846                 u32 sid, node_perm;
3847
3848                 if (family == PF_INET) {
3849                         addr4 = (struct sockaddr_in *)address;
3850                         snum = ntohs(addr4->sin_port);
3851                         addrp = (char *)&addr4->sin_addr.s_addr;
3852                 } else {
3853                         addr6 = (struct sockaddr_in6 *)address;
3854                         snum = ntohs(addr6->sin6_port);
3855                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3856                 }
3857
3858                 if (snum) {
3859                         int low, high;
3860
3861                         inet_get_local_port_range(&low, &high);
3862
3863                         if (snum < max(PROT_SOCK, low) || snum > high) {
3864                                 err = sel_netport_sid(sk->sk_protocol,
3865                                                       snum, &sid);
3866                                 if (err)
3867                                         goto out;
3868                                 ad.type = LSM_AUDIT_DATA_NET;
3869                                 ad.u.net = &net;
3870                                 ad.u.net->sport = htons(snum);
3871                                 ad.u.net->family = family;
3872                                 err = avc_has_perm(sksec->sid, sid,
3873                                                    sksec->sclass,
3874                                                    SOCKET__NAME_BIND, &ad);
3875                                 if (err)
3876                                         goto out;
3877                         }
3878                 }
3879
3880                 switch (sksec->sclass) {
3881                 case SECCLASS_TCP_SOCKET:
3882                         node_perm = TCP_SOCKET__NODE_BIND;
3883                         break;
3884
3885                 case SECCLASS_UDP_SOCKET:
3886                         node_perm = UDP_SOCKET__NODE_BIND;
3887                         break;
3888
3889                 case SECCLASS_DCCP_SOCKET:
3890                         node_perm = DCCP_SOCKET__NODE_BIND;
3891                         break;
3892
3893                 default:
3894                         node_perm = RAWIP_SOCKET__NODE_BIND;
3895                         break;
3896                 }
3897
3898                 err = sel_netnode_sid(addrp, family, &sid);
3899                 if (err)
3900                         goto out;
3901
3902                 ad.type = LSM_AUDIT_DATA_NET;
3903                 ad.u.net = &net;
3904                 ad.u.net->sport = htons(snum);
3905                 ad.u.net->family = family;
3906
3907                 if (family == PF_INET)
3908                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
3909                 else
3910                         ad.u.net->v6info.saddr = addr6->sin6_addr;
3911
3912                 err = avc_has_perm(sksec->sid, sid,
3913                                    sksec->sclass, node_perm, &ad);
3914                 if (err)
3915                         goto out;
3916         }
3917 out:
3918         return err;
3919 }
3920
3921 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3922 {
3923         struct sock *sk = sock->sk;
3924         struct sk_security_struct *sksec = sk->sk_security;
3925         int err;
3926
3927         err = sock_has_perm(current, sk, SOCKET__CONNECT);
3928         if (err)
3929                 return err;
3930
3931         /*
3932          * If a TCP or DCCP socket, check name_connect permission for the port.
3933          */
3934         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3935             sksec->sclass == SECCLASS_DCCP_SOCKET) {
3936                 struct common_audit_data ad;
3937                 struct lsm_network_audit net = {0,};
3938                 struct sockaddr_in *addr4 = NULL;
3939                 struct sockaddr_in6 *addr6 = NULL;
3940                 unsigned short snum;
3941                 u32 sid, perm;
3942
3943                 if (sk->sk_family == PF_INET) {
3944                         addr4 = (struct sockaddr_in *)address;
3945                         if (addrlen < sizeof(struct sockaddr_in))
3946                                 return -EINVAL;
3947                         snum = ntohs(addr4->sin_port);
3948                 } else {
3949                         addr6 = (struct sockaddr_in6 *)address;
3950                         if (addrlen < SIN6_LEN_RFC2133)
3951                                 return -EINVAL;
3952                         snum = ntohs(addr6->sin6_port);
3953                 }
3954
3955                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3956                 if (err)
3957                         goto out;
3958
3959                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3960                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3961
3962                 ad.type = LSM_AUDIT_DATA_NET;
3963                 ad.u.net = &net;
3964                 ad.u.net->dport = htons(snum);
3965                 ad.u.net->family = sk->sk_family;
3966                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3967                 if (err)
3968                         goto out;
3969         }
3970
3971         err = selinux_netlbl_socket_connect(sk, address);
3972
3973 out:
3974         return err;
3975 }
3976
3977 static int selinux_socket_listen(struct socket *sock, int backlog)
3978 {
3979         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3980 }
3981
3982 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3983 {
3984         int err;
3985         struct inode_security_struct *isec;
3986         struct inode_security_struct *newisec;
3987
3988         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3989         if (err)
3990                 return err;
3991
3992         newisec = SOCK_INODE(newsock)->i_security;
3993
3994         isec = SOCK_INODE(sock)->i_security;
3995         newisec->sclass = isec->sclass;
3996         newisec->sid = isec->sid;
3997         newisec->initialized = 1;
3998
3999         return 0;
4000 }
4001
4002 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4003                                   int size)
4004 {
4005         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4006 }
4007
4008 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4009                                   int size, int flags)
4010 {
4011         return sock_has_perm(current, sock->sk, SOCKET__READ);
4012 }
4013
4014 static int selinux_socket_getsockname(struct socket *sock)
4015 {
4016         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4017 }
4018
4019 static int selinux_socket_getpeername(struct socket *sock)
4020 {
4021         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4022 }
4023
4024 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4025 {
4026         int err;
4027
4028         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4029         if (err)
4030                 return err;
4031
4032         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4033 }
4034
4035 static int selinux_socket_getsockopt(struct socket *sock, int level,
4036                                      int optname)
4037 {
4038         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4039 }
4040
4041 static int selinux_socket_shutdown(struct socket *sock, int how)
4042 {
4043         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4044 }
4045
4046 static int selinux_socket_unix_stream_connect(struct sock *sock,
4047                                               struct sock *other,
4048                                               struct sock *newsk)
4049 {
4050         struct sk_security_struct *sksec_sock = sock->sk_security;
4051         struct sk_security_struct *sksec_other = other->sk_security;
4052         struct sk_security_struct *sksec_new = newsk->sk_security;
4053         struct common_audit_data ad;
4054         struct lsm_network_audit net = {0,};
4055         int err;
4056
4057         ad.type = LSM_AUDIT_DATA_NET;
4058         ad.u.net = &net;
4059         ad.u.net->sk = other;
4060
4061         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4062                            sksec_other->sclass,
4063                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4064         if (err)
4065                 return err;
4066
4067         /* server child socket */
4068         sksec_new->peer_sid = sksec_sock->sid;
4069         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4070                                     &sksec_new->sid);
4071         if (err)
4072                 return err;
4073
4074         /* connecting socket */
4075         sksec_sock->peer_sid = sksec_new->sid;
4076
4077         return 0;
4078 }
4079
4080 static int selinux_socket_unix_may_send(struct socket *sock,
4081                                         struct socket *other)
4082 {
4083         struct sk_security_struct *ssec = sock->sk->sk_security;
4084         struct sk_security_struct *osec = other->sk->sk_security;
4085         struct common_audit_data ad;
4086         struct lsm_network_audit net = {0,};
4087
4088         ad.type = LSM_AUDIT_DATA_NET;
4089         ad.u.net = &net;
4090         ad.u.net->sk = other->sk;
4091
4092         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4093                             &ad);
4094 }
4095
4096 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4097                                     u32 peer_sid,
4098                                     struct common_audit_data *ad)
4099 {
4100         int err;
4101         u32 if_sid;
4102         u32 node_sid;
4103
4104         err = sel_netif_sid(ifindex, &if_sid);
4105         if (err)
4106                 return err;
4107         err = avc_has_perm(peer_sid, if_sid,
4108                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4109         if (err)
4110                 return err;
4111
4112         err = sel_netnode_sid(addrp, family, &node_sid);
4113         if (err)
4114                 return err;
4115         return avc_has_perm(peer_sid, node_sid,
4116                             SECCLASS_NODE, NODE__RECVFROM, ad);
4117 }
4118
4119 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4120                                        u16 family)
4121 {
4122         int err = 0;
4123         struct sk_security_struct *sksec = sk->sk_security;
4124         u32 sk_sid = sksec->sid;
4125         struct common_audit_data ad;
4126         struct lsm_network_audit net = {0,};
4127         char *addrp;
4128
4129         ad.type = LSM_AUDIT_DATA_NET;
4130         ad.u.net = &net;
4131         ad.u.net->netif = skb->skb_iif;
4132         ad.u.net->family = family;
4133         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4134         if (err)
4135                 return err;
4136
4137         if (selinux_secmark_enabled()) {
4138                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4139                                    PACKET__RECV, &ad);
4140                 if (err)
4141                         return err;
4142         }
4143
4144         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4145         if (err)
4146                 return err;
4147         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4148
4149         return err;
4150 }
4151
4152 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4153 {
4154         int err;
4155         struct sk_security_struct *sksec = sk->sk_security;
4156         u16 family = sk->sk_family;
4157         u32 sk_sid = sksec->sid;
4158         struct common_audit_data ad;
4159         struct lsm_network_audit net = {0,};
4160         char *addrp;
4161         u8 secmark_active;
4162         u8 peerlbl_active;
4163
4164         if (family != PF_INET && family != PF_INET6)
4165                 return 0;
4166
4167         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4168         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4169                 family = PF_INET;
4170
4171         /* If any sort of compatibility mode is enabled then handoff processing
4172          * to the selinux_sock_rcv_skb_compat() function to deal with the
4173          * special handling.  We do this in an attempt to keep this function
4174          * as fast and as clean as possible. */
4175         if (!selinux_policycap_netpeer)
4176                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4177
4178         secmark_active = selinux_secmark_enabled();
4179         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4180         if (!secmark_active && !peerlbl_active)
4181                 return 0;
4182
4183         ad.type = LSM_AUDIT_DATA_NET;
4184         ad.u.net = &net;
4185         ad.u.net->netif = skb->skb_iif;
4186         ad.u.net->family = family;
4187         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4188         if (err)
4189                 return err;
4190
4191         if (peerlbl_active) {
4192                 u32 peer_sid;
4193
4194                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4195                 if (err)
4196                         return err;
4197                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4198                                                peer_sid, &ad);
4199                 if (err) {
4200                         selinux_netlbl_err(skb, err, 0);
4201                         return err;
4202                 }
4203                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4204                                    PEER__RECV, &ad);
4205                 if (err)
4206                         selinux_netlbl_err(skb, err, 0);
4207         }
4208
4209         if (secmark_active) {
4210                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4211                                    PACKET__RECV, &ad);
4212                 if (err)
4213                         return err;
4214         }
4215
4216         return err;
4217 }
4218
4219 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4220                                             int __user *optlen, unsigned len)
4221 {
4222         int err = 0;
4223         char *scontext;
4224         u32 scontext_len;
4225         struct sk_security_struct *sksec = sock->sk->sk_security;
4226         u32 peer_sid = SECSID_NULL;
4227
4228         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4229             sksec->sclass == SECCLASS_TCP_SOCKET)
4230                 peer_sid = sksec->peer_sid;
4231         if (peer_sid == SECSID_NULL)
4232                 return -ENOPROTOOPT;
4233
4234         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4235         if (err)
4236                 return err;
4237
4238         if (scontext_len > len) {
4239                 err = -ERANGE;
4240                 goto out_len;
4241         }
4242
4243         if (copy_to_user(optval, scontext, scontext_len))
4244                 err = -EFAULT;
4245
4246 out_len:
4247         if (put_user(scontext_len, optlen))
4248                 err = -EFAULT;
4249         kfree(scontext);
4250         return err;
4251 }
4252
4253 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4254 {
4255         u32 peer_secid = SECSID_NULL;
4256         u16 family;
4257
4258         if (skb && skb->protocol == htons(ETH_P_IP))
4259                 family = PF_INET;
4260         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4261                 family = PF_INET6;
4262         else if (sock)
4263                 family = sock->sk->sk_family;
4264         else
4265                 goto out;
4266
4267         if (sock && family == PF_UNIX)
4268                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4269         else if (skb)
4270                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4271
4272 out:
4273         *secid = peer_secid;
4274         if (peer_secid == SECSID_NULL)
4275                 return -EINVAL;
4276         return 0;
4277 }
4278
4279 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4280 {
4281         struct sk_security_struct *sksec;
4282
4283         sksec = kzalloc(sizeof(*sksec), priority);
4284         if (!sksec)
4285                 return -ENOMEM;
4286
4287         sksec->peer_sid = SECINITSID_UNLABELED;
4288         sksec->sid = SECINITSID_UNLABELED;
4289         selinux_netlbl_sk_security_reset(sksec);
4290         sk->sk_security = sksec;
4291
4292         return 0;
4293 }
4294
4295 static void selinux_sk_free_security(struct sock *sk)
4296 {
4297         struct sk_security_struct *sksec = sk->sk_security;
4298
4299         sk->sk_security = NULL;
4300         selinux_netlbl_sk_security_free(sksec);
4301         kfree(sksec);
4302 }
4303
4304 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4305 {
4306         struct sk_security_struct *sksec = sk->sk_security;
4307         struct sk_security_struct *newsksec = newsk->sk_security;
4308
4309         newsksec->sid = sksec->sid;
4310         newsksec->peer_sid = sksec->peer_sid;
4311         newsksec->sclass = sksec->sclass;
4312
4313         selinux_netlbl_sk_security_reset(newsksec);
4314 }
4315
4316 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4317 {
4318         if (!sk)
4319                 *secid = SECINITSID_ANY_SOCKET;
4320         else {
4321                 struct sk_security_struct *sksec = sk->sk_security;
4322
4323                 *secid = sksec->sid;
4324         }
4325 }
4326
4327 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4328 {
4329         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4330         struct sk_security_struct *sksec = sk->sk_security;
4331
4332         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4333             sk->sk_family == PF_UNIX)
4334                 isec->sid = sksec->sid;
4335         sksec->sclass = isec->sclass;
4336 }
4337
4338 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4339                                      struct request_sock *req)
4340 {
4341         struct sk_security_struct *sksec = sk->sk_security;
4342         int err;
4343         u16 family = sk->sk_family;
4344         u32 newsid;
4345         u32 peersid;
4346
4347         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4348         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4349                 family = PF_INET;
4350
4351         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4352         if (err)
4353                 return err;
4354         if (peersid == SECSID_NULL) {
4355                 req->secid = sksec->sid;
4356                 req->peer_secid = SECSID_NULL;
4357         } else {
4358                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4359                 if (err)
4360                         return err;
4361                 req->secid = newsid;
4362                 req->peer_secid = peersid;
4363         }
4364
4365         return selinux_netlbl_inet_conn_request(req, family);
4366 }
4367
4368 static void selinux_inet_csk_clone(struct sock *newsk,
4369                                    const struct request_sock *req)
4370 {
4371         struct sk_security_struct *newsksec = newsk->sk_security;
4372
4373         newsksec->sid = req->secid;
4374         newsksec->peer_sid = req->peer_secid;
4375         /* NOTE: Ideally, we should also get the isec->sid for the
4376            new socket in sync, but we don't have the isec available yet.
4377            So we will wait until sock_graft to do it, by which
4378            time it will have been created and available. */
4379
4380         /* We don't need to take any sort of lock here as we are the only
4381          * thread with access to newsksec */
4382         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4383 }
4384
4385 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4386 {
4387         u16 family = sk->sk_family;
4388         struct sk_security_struct *sksec = sk->sk_security;
4389
4390         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4391         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4392                 family = PF_INET;
4393
4394         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4395 }
4396
4397 static int selinux_secmark_relabel_packet(u32 sid)
4398 {
4399         const struct task_security_struct *__tsec;
4400         u32 tsid;
4401
4402         __tsec = current_security();
4403         tsid = __tsec->sid;
4404
4405         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4406 }
4407
4408 static void selinux_secmark_refcount_inc(void)
4409 {
4410         atomic_inc(&selinux_secmark_refcount);
4411 }
4412
4413 static void selinux_secmark_refcount_dec(void)
4414 {
4415         atomic_dec(&selinux_secmark_refcount);
4416 }
4417
4418 static void selinux_req_classify_flow(const struct request_sock *req,
4419                                       struct flowi *fl)
4420 {
4421         fl->flowi_secid = req->secid;
4422 }
4423
4424 static int selinux_tun_dev_create(void)
4425 {
4426         u32 sid = current_sid();
4427
4428         /* we aren't taking into account the "sockcreate" SID since the socket
4429          * that is being created here is not a socket in the traditional sense,
4430          * instead it is a private sock, accessible only to the kernel, and
4431          * representing a wide range of network traffic spanning multiple
4432          * connections unlike traditional sockets - check the TUN driver to
4433          * get a better understanding of why this socket is special */
4434
4435         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4436                             NULL);
4437 }
4438
4439 static void selinux_tun_dev_post_create(struct sock *sk)
4440 {
4441         struct sk_security_struct *sksec = sk->sk_security;
4442
4443         /* we don't currently perform any NetLabel based labeling here and it
4444          * isn't clear that we would want to do so anyway; while we could apply
4445          * labeling without the support of the TUN user the resulting labeled
4446          * traffic from the other end of the connection would almost certainly
4447          * cause confusion to the TUN user that had no idea network labeling
4448          * protocols were being used */
4449
4450         /* see the comments in selinux_tun_dev_create() about why we don't use
4451          * the sockcreate SID here */
4452
4453         sksec->sid = current_sid();
4454         sksec->sclass = SECCLASS_TUN_SOCKET;
4455 }
4456
4457 static int selinux_tun_dev_attach(struct sock *sk)
4458 {
4459         struct sk_security_struct *sksec = sk->sk_security;
4460         u32 sid = current_sid();
4461         int err;
4462
4463         err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4464                            TUN_SOCKET__RELABELFROM, NULL);
4465         if (err)
4466                 return err;
4467         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4468                            TUN_SOCKET__RELABELTO, NULL);
4469         if (err)
4470                 return err;
4471
4472         sksec->sid = sid;
4473
4474         return 0;
4475 }
4476
4477 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4478 {
4479         int err = 0;
4480         u32 perm;
4481         struct nlmsghdr *nlh;
4482         struct sk_security_struct *sksec = sk->sk_security;
4483
4484         if (skb->len < NLMSG_SPACE(0)) {
4485                 err = -EINVAL;
4486                 goto out;
4487         }
4488         nlh = nlmsg_hdr(skb);
4489
4490         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4491         if (err) {
4492                 if (err == -EINVAL) {
4493                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4494                                   "SELinux:  unrecognized netlink message"
4495                                   " type=%hu for sclass=%hu\n",
4496                                   nlh->nlmsg_type, sksec->sclass);
4497                         if (!selinux_enforcing || security_get_allow_unknown())
4498                                 err = 0;
4499                 }
4500
4501                 /* Ignore */
4502                 if (err == -ENOENT)
4503                         err = 0;
4504                 goto out;
4505         }
4506
4507         err = sock_has_perm(current, sk, perm);
4508 out:
4509         return err;
4510 }
4511
4512 #ifdef CONFIG_NETFILTER
4513
4514 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4515                                        u16 family)
4516 {
4517         int err;
4518         char *addrp;
4519         u32 peer_sid;
4520         struct common_audit_data ad;
4521         struct lsm_network_audit net = {0,};
4522         u8 secmark_active;
4523         u8 netlbl_active;
4524         u8 peerlbl_active;
4525
4526         if (!selinux_policycap_netpeer)
4527                 return NF_ACCEPT;
4528
4529         secmark_active = selinux_secmark_enabled();
4530         netlbl_active = netlbl_enabled();
4531         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4532         if (!secmark_active && !peerlbl_active)
4533                 return NF_ACCEPT;
4534
4535         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4536                 return NF_DROP;
4537
4538         ad.type = LSM_AUDIT_DATA_NET;
4539         ad.u.net = &net;
4540         ad.u.net->netif = ifindex;
4541         ad.u.net->family = family;
4542         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4543                 return NF_DROP;
4544
4545         if (peerlbl_active) {
4546                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4547                                                peer_sid, &ad);
4548                 if (err) {
4549                         selinux_netlbl_err(skb, err, 1);
4550                         return NF_DROP;
4551                 }
4552         }
4553
4554         if (secmark_active)
4555                 if (avc_has_perm(peer_sid, skb->secmark,
4556                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4557                         return NF_DROP;
4558
4559         if (netlbl_active)
4560                 /* we do this in the FORWARD path and not the POST_ROUTING
4561                  * path because we want to make sure we apply the necessary
4562                  * labeling before IPsec is applied so we can leverage AH
4563                  * protection */
4564                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4565                         return NF_DROP;
4566
4567         return NF_ACCEPT;
4568 }
4569
4570 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4571                                          struct sk_buff *skb,
4572                                          const struct net_device *in,
4573                                          const struct net_device *out,
4574                                          int (*okfn)(struct sk_buff *))
4575 {
4576         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4577 }
4578
4579 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4580 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4581                                          struct sk_buff *skb,
4582                                          const struct net_device *in,
4583                                          const struct net_device *out,
4584                                          int (*okfn)(struct sk_buff *))
4585 {
4586         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4587 }
4588 #endif  /* IPV6 */
4589
4590 static unsigned int selinux_ip_output(struct sk_buff *skb,
4591                                       u16 family)
4592 {
4593         u32 sid;
4594
4595         if (!netlbl_enabled())
4596                 return NF_ACCEPT;
4597
4598         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4599          * because we want to make sure we apply the necessary labeling
4600          * before IPsec is applied so we can leverage AH protection */
4601         if (skb->sk) {
4602                 struct sk_security_struct *sksec = skb->sk->sk_security;
4603                 sid = sksec->sid;
4604         } else
4605                 sid = SECINITSID_KERNEL;
4606         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4607                 return NF_DROP;
4608
4609         return NF_ACCEPT;
4610 }
4611
4612 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4613                                         struct sk_buff *skb,
4614                                         const struct net_device *in,
4615                                         const struct net_device *out,
4616                                         int (*okfn)(struct sk_buff *))
4617 {
4618         return selinux_ip_output(skb, PF_INET);
4619 }
4620
4621 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4622                                                 int ifindex,
4623                                                 u16 family)
4624 {
4625         struct sock *sk = skb->sk;
4626         struct sk_security_struct *sksec;
4627         struct common_audit_data ad;
4628         struct lsm_network_audit net = {0,};
4629         char *addrp;
4630         u8 proto;
4631
4632         if (sk == NULL)
4633                 return NF_ACCEPT;
4634         sksec = sk->sk_security;
4635
4636         ad.type = LSM_AUDIT_DATA_NET;
4637         ad.u.net = &net;
4638         ad.u.net->netif = ifindex;
4639         ad.u.net->family = family;
4640         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4641                 return NF_DROP;
4642
4643         if (selinux_secmark_enabled())
4644                 if (avc_has_perm(sksec->sid, skb->secmark,
4645                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4646                         return NF_DROP_ERR(-ECONNREFUSED);
4647
4648         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4649                 return NF_DROP_ERR(-ECONNREFUSED);
4650
4651         return NF_ACCEPT;
4652 }
4653
4654 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4655                                          u16 family)
4656 {
4657         u32 secmark_perm;
4658         u32 peer_sid;
4659         struct sock *sk;
4660         struct common_audit_data ad;
4661         struct lsm_network_audit net = {0,};
4662         char *addrp;
4663         u8 secmark_active;
4664         u8 peerlbl_active;
4665
4666         /* If any sort of compatibility mode is enabled then handoff processing
4667          * to the selinux_ip_postroute_compat() function to deal with the
4668          * special handling.  We do this in an attempt to keep this function
4669          * as fast and as clean as possible. */
4670         if (!selinux_policycap_netpeer)
4671                 return selinux_ip_postroute_compat(skb, ifindex, family);
4672 #ifdef CONFIG_XFRM
4673         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4674          * packet transformation so allow the packet to pass without any checks
4675          * since we'll have another chance to perform access control checks
4676          * when the packet is on it's final way out.
4677          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4678          *       is NULL, in this case go ahead and apply access control. */
4679         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4680                 return NF_ACCEPT;
4681 #endif
4682         secmark_active = selinux_secmark_enabled();
4683         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4684         if (!secmark_active && !peerlbl_active)
4685                 return NF_ACCEPT;
4686
4687         /* if the packet is being forwarded then get the peer label from the
4688          * packet itself; otherwise check to see if it is from a local
4689          * application or the kernel, if from an application get the peer label
4690          * from the sending socket, otherwise use the kernel's sid */
4691         sk = skb->sk;
4692         if (sk == NULL) {
4693                 if (skb->skb_iif) {
4694                         secmark_perm = PACKET__FORWARD_OUT;
4695                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4696                                 return NF_DROP;
4697                 } else {
4698                         secmark_perm = PACKET__SEND;
4699                         peer_sid = SECINITSID_KERNEL;
4700                 }
4701         } else {
4702                 struct sk_security_struct *sksec = sk->sk_security;
4703                 peer_sid = sksec->sid;
4704                 secmark_perm = PACKET__SEND;
4705         }
4706
4707         ad.type = LSM_AUDIT_DATA_NET;
4708         ad.u.net = &net;
4709         ad.u.net->netif = ifindex;
4710         ad.u.net->family = family;
4711         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4712                 return NF_DROP;
4713
4714         if (secmark_active)
4715                 if (avc_has_perm(peer_sid, skb->secmark,
4716                                  SECCLASS_PACKET, secmark_perm, &ad))
4717                         return NF_DROP_ERR(-ECONNREFUSED);
4718
4719         if (peerlbl_active) {
4720                 u32 if_sid;
4721                 u32 node_sid;
4722
4723                 if (sel_netif_sid(ifindex, &if_sid))
4724                         return NF_DROP;
4725                 if (avc_has_perm(peer_sid, if_sid,
4726                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4727                         return NF_DROP_ERR(-ECONNREFUSED);
4728
4729                 if (sel_netnode_sid(addrp, family, &node_sid))
4730                         return NF_DROP;
4731                 if (avc_has_perm(peer_sid, node_sid,
4732                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4733                         return NF_DROP_ERR(-ECONNREFUSED);
4734         }
4735
4736         return NF_ACCEPT;
4737 }
4738
4739 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4740                                            struct sk_buff *skb,
4741                                            const struct net_device *in,
4742                                            const struct net_device *out,
4743                                            int (*okfn)(struct sk_buff *))
4744 {
4745         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4746 }
4747
4748 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4749 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4750                                            struct sk_buff *skb,
4751                                            const struct net_device *in,
4752                                            const struct net_device *out,
4753                                            int (*okfn)(struct sk_buff *))
4754 {
4755         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4756 }
4757 #endif  /* IPV6 */
4758
4759 #endif  /* CONFIG_NETFILTER */
4760
4761 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4762 {
4763         int err;
4764
4765         err = cap_netlink_send(sk, skb);
4766         if (err)
4767                 return err;
4768
4769         return selinux_nlmsg_perm(sk, skb);
4770 }
4771
4772 static int ipc_alloc_security(struct task_struct *task,
4773                               struct kern_ipc_perm *perm,
4774                               u16 sclass)
4775 {
4776         struct ipc_security_struct *isec;
4777         u32 sid;
4778
4779         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4780         if (!isec)
4781                 return -ENOMEM;
4782
4783         sid = task_sid(task);
4784         isec->sclass = sclass;
4785         isec->sid = sid;
4786         perm->security = isec;
4787
4788         return 0;
4789 }
4790
4791 static void ipc_free_security(struct kern_ipc_perm *perm)
4792 {
4793         struct ipc_security_struct *isec = perm->security;
4794         perm->security = NULL;
4795         kfree(isec);
4796 }
4797
4798 static int msg_msg_alloc_security(struct msg_msg *msg)
4799 {
4800         struct msg_security_struct *msec;
4801
4802         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4803         if (!msec)
4804                 return -ENOMEM;
4805
4806         msec->sid = SECINITSID_UNLABELED;
4807         msg->security = msec;
4808
4809         return 0;
4810 }
4811
4812 static void msg_msg_free_security(struct msg_msg *msg)
4813 {
4814         struct msg_security_struct *msec = msg->security;
4815
4816         msg->security = NULL;
4817         kfree(msec);
4818 }
4819
4820 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4821                         u32 perms)
4822 {
4823         struct ipc_security_struct *isec;
4824         struct common_audit_data ad;
4825         u32 sid = current_sid();
4826
4827         isec = ipc_perms->security;
4828
4829         ad.type = LSM_AUDIT_DATA_IPC;
4830         ad.u.ipc_id = ipc_perms->key;
4831
4832         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4833 }
4834
4835 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4836 {
4837         return msg_msg_alloc_security(msg);
4838 }
4839
4840 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4841 {
4842         msg_msg_free_security(msg);
4843 }
4844
4845 /* message queue security operations */
4846 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4847 {
4848         struct ipc_security_struct *isec;
4849         struct common_audit_data ad;
4850         u32 sid = current_sid();
4851         int rc;
4852
4853         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4854         if (rc)
4855                 return rc;
4856
4857         isec = msq->q_perm.security;
4858
4859         ad.type = LSM_AUDIT_DATA_IPC;
4860         ad.u.ipc_id = msq->q_perm.key;
4861
4862         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4863                           MSGQ__CREATE, &ad);
4864         if (rc) {
4865                 ipc_free_security(&msq->q_perm);
4866                 return rc;
4867         }
4868         return 0;
4869 }
4870
4871 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4872 {
4873         ipc_free_security(&msq->q_perm);
4874 }
4875
4876 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4877 {
4878         struct ipc_security_struct *isec;
4879         struct common_audit_data ad;
4880         u32 sid = current_sid();
4881
4882         isec = msq->q_perm.security;
4883
4884         ad.type = LSM_AUDIT_DATA_IPC;
4885         ad.u.ipc_id = msq->q_perm.key;
4886
4887         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4888                             MSGQ__ASSOCIATE, &ad);
4889 }
4890
4891 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4892 {
4893         int err;
4894         int perms;
4895
4896         switch (cmd) {
4897         case IPC_INFO:
4898         case MSG_INFO:
4899                 /* No specific object, just general system-wide information. */
4900                 return task_has_system(current, SYSTEM__IPC_INFO);
4901         case IPC_STAT:
4902         case MSG_STAT:
4903                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4904                 break;
4905         case IPC_SET:
4906                 perms = MSGQ__SETATTR;
4907                 break;
4908         case IPC_RMID:
4909                 perms = MSGQ__DESTROY;
4910                 break;
4911         default:
4912                 return 0;
4913         }
4914
4915         err = ipc_has_perm(&msq->q_perm, perms);
4916         return err;
4917 }
4918
4919 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4920 {
4921         struct ipc_security_struct *isec;
4922         struct msg_security_struct *msec;
4923         struct common_audit_data ad;
4924         u32 sid = current_sid();
4925         int rc;
4926
4927         isec = msq->q_perm.security;
4928         msec = msg->security;
4929
4930         /*
4931          * First time through, need to assign label to the message
4932          */
4933         if (msec->sid == SECINITSID_UNLABELED) {
4934                 /*
4935                  * Compute new sid based on current process and
4936                  * message queue this message will be stored in
4937                  */
4938                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4939                                              NULL, &msec->sid);
4940                 if (rc)
4941                         return rc;
4942         }
4943
4944         ad.type = LSM_AUDIT_DATA_IPC;
4945         ad.u.ipc_id = msq->q_perm.key;
4946
4947         /* Can this process write to the queue? */
4948         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4949                           MSGQ__WRITE, &ad);
4950         if (!rc)
4951                 /* Can this process send the message */
4952                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4953                                   MSG__SEND, &ad);
4954         if (!rc)
4955                 /* Can the message be put in the queue? */
4956                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4957                                   MSGQ__ENQUEUE, &ad);
4958
4959         return rc;
4960 }
4961
4962 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4963                                     struct task_struct *target,
4964                                     long type, int mode)
4965 {
4966         struct ipc_security_struct *isec;
4967         struct msg_security_struct *msec;
4968         struct common_audit_data ad;
4969         u32 sid = task_sid(target);
4970         int rc;
4971
4972         isec = msq->q_perm.security;
4973         msec = msg->security;
4974
4975         ad.type = LSM_AUDIT_DATA_IPC;
4976         ad.u.ipc_id = msq->q_perm.key;
4977
4978         rc = avc_has_perm(sid, isec->sid,
4979                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4980         if (!rc)
4981                 rc = avc_has_perm(sid, msec->sid,
4982                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4983         return rc;
4984 }
4985
4986 /* Shared Memory security operations */
4987 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4988 {
4989         struct ipc_security_struct *isec;
4990         struct common_audit_data ad;
4991         u32 sid = current_sid();
4992         int rc;
4993
4994         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4995         if (rc)
4996                 return rc;
4997
4998         isec = shp->shm_perm.security;
4999
5000         ad.type = LSM_AUDIT_DATA_IPC;
5001         ad.u.ipc_id = shp->shm_perm.key;
5002
5003         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5004                           SHM__CREATE, &ad);
5005         if (rc) {
5006                 ipc_free_security(&shp->shm_perm);
5007                 return rc;
5008         }
5009         return 0;
5010 }
5011
5012 static void selinux_shm_free_security(struct shmid_kernel *shp)
5013 {
5014         ipc_free_security(&shp->shm_perm);
5015 }
5016
5017 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5018 {
5019         struct ipc_security_struct *isec;
5020         struct common_audit_data ad;
5021         u32 sid = current_sid();
5022
5023         isec = shp->shm_perm.security;
5024
5025         ad.type = LSM_AUDIT_DATA_IPC;
5026         ad.u.ipc_id = shp->shm_perm.key;
5027
5028         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5029                             SHM__ASSOCIATE, &ad);
5030 }
5031
5032 /* Note, at this point, shp is locked down */
5033 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5034 {
5035         int perms;
5036         int err;
5037
5038         switch (cmd) {
5039         case IPC_INFO:
5040         case SHM_INFO:
5041                 /* No specific object, just general system-wide information. */
5042                 return task_has_system(current, SYSTEM__IPC_INFO);
5043         case IPC_STAT:
5044         case SHM_STAT:
5045                 perms = SHM__GETATTR | SHM__ASSOCIATE;
5046                 break;
5047         case IPC_SET:
5048                 perms = SHM__SETATTR;
5049                 break;
5050         case SHM_LOCK:
5051         case SHM_UNLOCK:
5052                 perms = SHM__LOCK;
5053                 break;
5054         case IPC_RMID:
5055                 perms = SHM__DESTROY;
5056                 break;
5057         default:
5058                 return 0;
5059         }
5060
5061         err = ipc_has_perm(&shp->shm_perm, perms);
5062         return err;
5063 }
5064
5065 static int selinux_shm_shmat(struct shmid_kernel *shp,
5066                              char __user *shmaddr, int shmflg)
5067 {
5068         u32 perms;
5069
5070         if (shmflg & SHM_RDONLY)
5071                 perms = SHM__READ;
5072         else
5073                 perms = SHM__READ | SHM__WRITE;
5074
5075         return ipc_has_perm(&shp->shm_perm, perms);
5076 }
5077
5078 /* Semaphore security operations */
5079 static int selinux_sem_alloc_security(struct sem_array *sma)
5080 {
5081         struct ipc_security_struct *isec;
5082         struct common_audit_data ad;
5083         u32 sid = current_sid();
5084         int rc;
5085
5086         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5087         if (rc)
5088                 return rc;
5089
5090         isec = sma->sem_perm.security;
5091
5092         ad.type = LSM_AUDIT_DATA_IPC;
5093         ad.u.ipc_id = sma->sem_perm.key;
5094
5095         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5096                           SEM__CREATE, &ad);
5097         if (rc) {
5098                 ipc_free_security(&sma->sem_perm);
5099                 return rc;
5100         }
5101         return 0;
5102 }
5103
5104 static void selinux_sem_free_security(struct sem_array *sma)
5105 {
5106         ipc_free_security(&sma->sem_perm);
5107 }
5108
5109 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5110 {
5111         struct ipc_security_struct *isec;
5112         struct common_audit_data ad;
5113         u32 sid = current_sid();
5114
5115         isec = sma->sem_perm.security;
5116
5117         ad.type = LSM_AUDIT_DATA_IPC;
5118         ad.u.ipc_id = sma->sem_perm.key;
5119
5120         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5121                             SEM__ASSOCIATE, &ad);
5122 }
5123
5124 /* Note, at this point, sma is locked down */
5125 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5126 {
5127         int err;
5128         u32 perms;
5129
5130         switch (cmd) {
5131         case IPC_INFO:
5132         case SEM_INFO:
5133                 /* No specific object, just general system-wide information. */
5134                 return task_has_system(current, SYSTEM__IPC_INFO);
5135         case GETPID:
5136         case GETNCNT:
5137         case GETZCNT:
5138                 perms = SEM__GETATTR;
5139                 break;
5140         case GETVAL:
5141         case GETALL:
5142                 perms = SEM__READ;
5143                 break;
5144         case SETVAL:
5145         case SETALL:
5146                 perms = SEM__WRITE;
5147                 break;
5148         case IPC_RMID:
5149                 perms = SEM__DESTROY;
5150                 break;
5151         case IPC_SET:
5152                 perms = SEM__SETATTR;
5153                 break;
5154         case IPC_STAT:
5155         case SEM_STAT:
5156                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5157                 break;
5158         default:
5159                 return 0;
5160         }
5161
5162         err = ipc_has_perm(&sma->sem_perm, perms);
5163         return err;
5164 }
5165
5166 static int selinux_sem_semop(struct sem_array *sma,
5167                              struct sembuf *sops, unsigned nsops, int alter)
5168 {
5169         u32 perms;
5170
5171         if (alter)
5172                 perms = SEM__READ | SEM__WRITE;
5173         else
5174                 perms = SEM__READ;
5175
5176         return ipc_has_perm(&sma->sem_perm, perms);
5177 }
5178
5179 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5180 {
5181         u32 av = 0;
5182
5183         av = 0;
5184         if (flag & S_IRUGO)
5185                 av |= IPC__UNIX_READ;
5186         if (flag & S_IWUGO)
5187                 av |= IPC__UNIX_WRITE;
5188
5189         if (av == 0)
5190                 return 0;
5191
5192         return ipc_has_perm(ipcp, av);
5193 }
5194
5195 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5196 {
5197         struct ipc_security_struct *isec = ipcp->security;
5198         *secid = isec->sid;
5199 }
5200
5201 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5202 {
5203         if (inode)
5204                 inode_doinit_with_dentry(inode, dentry);
5205 }
5206
5207 static int selinux_getprocattr(struct task_struct *p,
5208                                char *name, char **value)
5209 {
5210         const struct task_security_struct *__tsec;
5211         u32 sid;
5212         int error;
5213         unsigned len;
5214
5215         if (current != p) {
5216                 error = current_has_perm(p, PROCESS__GETATTR);
5217                 if (error)
5218                         return error;
5219         }
5220
5221         rcu_read_lock();
5222         __tsec = __task_cred(p)->security;
5223
5224         if (!strcmp(name, "current"))
5225                 sid = __tsec->sid;
5226         else if (!strcmp(name, "prev"))
5227                 sid = __tsec->osid;
5228         else if (!strcmp(name, "exec"))
5229                 sid = __tsec->exec_sid;
5230         else if (!strcmp(name, "fscreate"))
5231                 sid = __tsec->create_sid;
5232         else if (!strcmp(name, "keycreate"))
5233                 sid = __tsec->keycreate_sid;
5234         else if (!strcmp(name, "sockcreate"))
5235                 sid = __tsec->sockcreate_sid;
5236         else
5237                 goto invalid;
5238         rcu_read_unlock();
5239
5240         if (!sid)
5241                 return 0;
5242
5243         error = security_sid_to_context(sid, value, &len);
5244         if (error)
5245                 return error;
5246         return len;
5247
5248 invalid:
5249         rcu_read_unlock();
5250         return -EINVAL;
5251 }
5252
5253 static int selinux_setprocattr(struct task_struct *p,
5254                                char *name, void *value, size_t size)
5255 {
5256         struct task_security_struct *tsec;
5257         struct task_struct *tracer;
5258         struct cred *new;
5259         u32 sid = 0, ptsid;
5260         int error;
5261         char *str = value;
5262
5263         if (current != p) {
5264                 /* SELinux only allows a process to change its own
5265                    security attributes. */
5266                 return -EACCES;
5267         }
5268
5269         /*
5270          * Basic control over ability to set these attributes at all.
5271          * current == p, but we'll pass them separately in case the
5272          * above restriction is ever removed.
5273          */
5274         if (!strcmp(name, "exec"))
5275                 error = current_has_perm(p, PROCESS__SETEXEC);
5276         else if (!strcmp(name, "fscreate"))
5277                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5278         else if (!strcmp(name, "keycreate"))
5279                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5280         else if (!strcmp(name, "sockcreate"))
5281                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5282         else if (!strcmp(name, "current"))
5283                 error = current_has_perm(p, PROCESS__SETCURRENT);
5284         else
5285                 error = -EINVAL;
5286         if (error)
5287                 return error;
5288
5289         /* Obtain a SID for the context, if one was specified. */
5290         if (size && str[1] && str[1] != '\n') {
5291                 if (str[size-1] == '\n') {
5292                         str[size-1] = 0;
5293                         size--;
5294                 }
5295                 error = security_context_to_sid(value, size, &sid);
5296                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5297                         if (!capable(CAP_MAC_ADMIN)) {
5298                                 struct audit_buffer *ab;
5299                                 size_t audit_size;
5300
5301                                 /* We strip a nul only if it is at the end, otherwise the
5302                                  * context contains a nul and we should audit that */
5303                                 if (str[size - 1] == '\0')
5304                                         audit_size = size - 1;
5305                                 else
5306                                         audit_size = size;
5307                                 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5308                                 audit_log_format(ab, "op=fscreate invalid_context=");
5309                                 audit_log_n_untrustedstring(ab, value, audit_size);
5310                                 audit_log_end(ab);
5311
5312                                 return error;
5313                         }
5314                         error = security_context_to_sid_force(value, size,
5315                                                               &sid);
5316                 }
5317                 if (error)
5318                         return error;
5319         }
5320
5321         new = prepare_creds();
5322         if (!new)
5323                 return -ENOMEM;
5324
5325         /* Permission checking based on the specified context is
5326            performed during the actual operation (execve,
5327            open/mkdir/...), when we know the full context of the
5328            operation.  See selinux_bprm_set_creds for the execve
5329            checks and may_create for the file creation checks. The
5330            operation will then fail if the context is not permitted. */
5331         tsec = new->security;
5332         if (!strcmp(name, "exec")) {
5333                 tsec->exec_sid = sid;
5334         } else if (!strcmp(name, "fscreate")) {
5335                 tsec->create_sid = sid;
5336         } else if (!strcmp(name, "keycreate")) {
5337                 error = may_create_key(sid, p);
5338                 if (error)
5339                         goto abort_change;
5340                 tsec->keycreate_sid = sid;
5341         } else if (!strcmp(name, "sockcreate")) {
5342                 tsec->sockcreate_sid = sid;
5343         } else if (!strcmp(name, "current")) {
5344                 error = -EINVAL;
5345                 if (sid == 0)
5346                         goto abort_change;
5347
5348                 /* Only allow single threaded processes to change context */
5349                 error = -EPERM;
5350                 if (!current_is_single_threaded()) {
5351                         error = security_bounded_transition(tsec->sid, sid);
5352                         if (error)
5353                                 goto abort_change;
5354                 }
5355
5356                 /* Check permissions for the transition. */
5357                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5358                                      PROCESS__DYNTRANSITION, NULL);
5359                 if (error)
5360                         goto abort_change;
5361
5362                 /* Check for ptracing, and update the task SID if ok.
5363                    Otherwise, leave SID unchanged and fail. */
5364                 ptsid = 0;
5365                 task_lock(p);
5366                 tracer = ptrace_parent(p);
5367                 if (tracer)
5368                         ptsid = task_sid(tracer);
5369                 task_unlock(p);
5370
5371                 if (tracer) {
5372                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5373                                              PROCESS__PTRACE, NULL);
5374                         if (error)
5375                                 goto abort_change;
5376                 }
5377
5378                 tsec->sid = sid;
5379         } else {
5380                 error = -EINVAL;
5381                 goto abort_change;
5382         }
5383
5384         commit_creds(new);
5385         return size;
5386
5387 abort_change:
5388         abort_creds(new);
5389         return error;
5390 }
5391
5392 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5393 {
5394         return security_sid_to_context(secid, secdata, seclen);
5395 }
5396
5397 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5398 {
5399         return security_context_to_sid(secdata, seclen, secid);
5400 }
5401
5402 static void selinux_release_secctx(char *secdata, u32 seclen)
5403 {
5404         kfree(secdata);
5405 }
5406
5407 /*
5408  *      called with inode->i_mutex locked
5409  */
5410 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5411 {
5412         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5413 }
5414
5415 /*
5416  *      called with inode->i_mutex locked
5417  */
5418 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5419 {
5420         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5421 }
5422
5423 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5424 {
5425         int len = 0;
5426         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5427                                                 ctx, true);
5428         if (len < 0)
5429                 return len;
5430         *ctxlen = len;
5431         return 0;
5432 }
5433 #ifdef CONFIG_KEYS
5434
5435 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5436                              unsigned long flags)
5437 {
5438         const struct task_security_struct *tsec;
5439         struct key_security_struct *ksec;
5440
5441         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5442         if (!ksec)
5443                 return -ENOMEM;
5444
5445         tsec = cred->security;
5446         if (tsec->keycreate_sid)
5447                 ksec->sid = tsec->keycreate_sid;
5448         else
5449                 ksec->sid = tsec->sid;
5450
5451         k->security = ksec;
5452         return 0;
5453 }
5454
5455 static void selinux_key_free(struct key *k)
5456 {
5457         struct key_security_struct *ksec = k->security;
5458
5459         k->security = NULL;
5460         kfree(ksec);
5461 }
5462
5463 static int selinux_key_permission(key_ref_t key_ref,
5464                                   const struct cred *cred,
5465                                   key_perm_t perm)
5466 {
5467         struct key *key;
5468         struct key_security_struct *ksec;
5469         u32 sid;
5470
5471         /* if no specific permissions are requested, we skip the
5472            permission check. No serious, additional covert channels
5473            appear to be created. */
5474         if (perm == 0)
5475                 return 0;
5476
5477         sid = cred_sid(cred);
5478
5479         key = key_ref_to_ptr(key_ref);
5480         ksec = key->security;
5481
5482         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5483 }
5484
5485 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5486 {
5487         struct key_security_struct *ksec = key->security;
5488         char *context = NULL;
5489         unsigned len;
5490         int rc;
5491
5492         rc = security_sid_to_context(ksec->sid, &context, &len);
5493         if (!rc)
5494                 rc = len;
5495         *_buffer = context;
5496         return rc;
5497 }
5498
5499 #endif
5500
5501 static struct security_operations selinux_ops = {
5502         .name =                         "selinux",
5503
5504         .ptrace_access_check =          selinux_ptrace_access_check,
5505         .ptrace_traceme =               selinux_ptrace_traceme,
5506         .capget =                       selinux_capget,
5507         .capset =                       selinux_capset,
5508         .capable =                      selinux_capable,
5509         .quotactl =                     selinux_quotactl,
5510         .quota_on =                     selinux_quota_on,
5511         .syslog =                       selinux_syslog,
5512         .vm_enough_memory =             selinux_vm_enough_memory,
5513
5514         .netlink_send =                 selinux_netlink_send,
5515
5516         .bprm_set_creds =               selinux_bprm_set_creds,
5517         .bprm_committing_creds =        selinux_bprm_committing_creds,
5518         .bprm_committed_creds =         selinux_bprm_committed_creds,
5519         .bprm_secureexec =              selinux_bprm_secureexec,
5520
5521         .sb_alloc_security =            selinux_sb_alloc_security,
5522         .sb_free_security =             selinux_sb_free_security,
5523         .sb_copy_data =                 selinux_sb_copy_data,
5524         .sb_remount =                   selinux_sb_remount,
5525         .sb_kern_mount =                selinux_sb_kern_mount,
5526         .sb_show_options =              selinux_sb_show_options,
5527         .sb_statfs =                    selinux_sb_statfs,
5528         .sb_mount =                     selinux_mount,
5529         .sb_umount =                    selinux_umount,
5530         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5531         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5532         .sb_parse_opts_str =            selinux_parse_opts_str,
5533
5534
5535         .inode_alloc_security =         selinux_inode_alloc_security,
5536         .inode_free_security =          selinux_inode_free_security,
5537         .inode_init_security =          selinux_inode_init_security,
5538         .inode_create =                 selinux_inode_create,
5539         .inode_link =                   selinux_inode_link,
5540         .inode_unlink =                 selinux_inode_unlink,
5541         .inode_symlink =                selinux_inode_symlink,
5542         .inode_mkdir =                  selinux_inode_mkdir,
5543         .inode_rmdir =                  selinux_inode_rmdir,
5544         .inode_mknod =                  selinux_inode_mknod,
5545         .inode_rename =                 selinux_inode_rename,
5546         .inode_readlink =               selinux_inode_readlink,
5547         .inode_follow_link =            selinux_inode_follow_link,
5548         .inode_permission =             selinux_inode_permission,
5549         .inode_setattr =                selinux_inode_setattr,
5550         .inode_getattr =                selinux_inode_getattr,
5551         .inode_setxattr =               selinux_inode_setxattr,
5552         .inode_post_setxattr =          selinux_inode_post_setxattr,
5553         .inode_getxattr =               selinux_inode_getxattr,
5554         .inode_listxattr =              selinux_inode_listxattr,
5555         .inode_removexattr =            selinux_inode_removexattr,
5556         .inode_getsecurity =            selinux_inode_getsecurity,
5557         .inode_setsecurity =            selinux_inode_setsecurity,
5558         .inode_listsecurity =           selinux_inode_listsecurity,
5559         .inode_getsecid =               selinux_inode_getsecid,
5560
5561         .file_permission =              selinux_file_permission,
5562         .file_alloc_security =          selinux_file_alloc_security,
5563         .file_free_security =           selinux_file_free_security,
5564         .file_ioctl =                   selinux_file_ioctl,
5565         .file_mmap =                    selinux_file_mmap,
5566         .file_mprotect =                selinux_file_mprotect,
5567         .file_lock =                    selinux_file_lock,
5568         .file_fcntl =                   selinux_file_fcntl,
5569         .file_set_fowner =              selinux_file_set_fowner,
5570         .file_send_sigiotask =          selinux_file_send_sigiotask,
5571         .file_receive =                 selinux_file_receive,
5572
5573         .file_open =                    selinux_file_open,
5574
5575         .task_create =                  selinux_task_create,
5576         .cred_alloc_blank =             selinux_cred_alloc_blank,
5577         .cred_free =                    selinux_cred_free,
5578         .cred_prepare =                 selinux_cred_prepare,
5579         .cred_transfer =                selinux_cred_transfer,
5580         .kernel_act_as =                selinux_kernel_act_as,
5581         .kernel_create_files_as =       selinux_kernel_create_files_as,
5582         .kernel_module_request =        selinux_kernel_module_request,
5583         .task_setpgid =                 selinux_task_setpgid,
5584         .task_getpgid =                 selinux_task_getpgid,
5585         .task_getsid =                  selinux_task_getsid,
5586         .task_getsecid =                selinux_task_getsecid,
5587         .task_setnice =                 selinux_task_setnice,
5588         .task_setioprio =               selinux_task_setioprio,
5589         .task_getioprio =               selinux_task_getioprio,
5590         .task_setrlimit =               selinux_task_setrlimit,
5591         .task_setscheduler =            selinux_task_setscheduler,
5592         .task_getscheduler =            selinux_task_getscheduler,
5593         .task_movememory =              selinux_task_movememory,
5594         .task_kill =                    selinux_task_kill,
5595         .task_wait =                    selinux_task_wait,
5596         .task_to_inode =                selinux_task_to_inode,
5597
5598         .ipc_permission =               selinux_ipc_permission,
5599         .ipc_getsecid =                 selinux_ipc_getsecid,
5600
5601         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5602         .msg_msg_free_security =        selinux_msg_msg_free_security,
5603
5604         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5605         .msg_queue_free_security =      selinux_msg_queue_free_security,
5606         .msg_queue_associate =          selinux_msg_queue_associate,
5607         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5608         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5609         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5610
5611         .shm_alloc_security =           selinux_shm_alloc_security,
5612         .shm_free_security =            selinux_shm_free_security,
5613         .shm_associate =                selinux_shm_associate,
5614         .shm_shmctl =                   selinux_shm_shmctl,
5615         .shm_shmat =                    selinux_shm_shmat,
5616
5617         .sem_alloc_security =           selinux_sem_alloc_security,
5618         .sem_free_security =            selinux_sem_free_security,
5619         .sem_associate =                selinux_sem_associate,
5620         .sem_semctl =                   selinux_sem_semctl,
5621         .sem_semop =                    selinux_sem_semop,
5622
5623         .d_instantiate =                selinux_d_instantiate,
5624
5625         .getprocattr =                  selinux_getprocattr,
5626         .setprocattr =                  selinux_setprocattr,
5627
5628         .secid_to_secctx =              selinux_secid_to_secctx,
5629         .secctx_to_secid =              selinux_secctx_to_secid,
5630         .release_secctx =               selinux_release_secctx,
5631         .inode_notifysecctx =           selinux_inode_notifysecctx,
5632         .inode_setsecctx =              selinux_inode_setsecctx,
5633         .inode_getsecctx =              selinux_inode_getsecctx,
5634
5635         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5636         .unix_may_send =                selinux_socket_unix_may_send,
5637
5638         .socket_create =                selinux_socket_create,
5639         .socket_post_create =           selinux_socket_post_create,
5640         .socket_bind =                  selinux_socket_bind,
5641         .socket_connect =               selinux_socket_connect,
5642         .socket_listen =                selinux_socket_listen,
5643         .socket_accept =                selinux_socket_accept,
5644         .socket_sendmsg =               selinux_socket_sendmsg,
5645         .socket_recvmsg =               selinux_socket_recvmsg,
5646         .socket_getsockname =           selinux_socket_getsockname,
5647         .socket_getpeername =           selinux_socket_getpeername,
5648         .socket_getsockopt =            selinux_socket_getsockopt,
5649         .socket_setsockopt =            selinux_socket_setsockopt,
5650         .socket_shutdown =              selinux_socket_shutdown,
5651         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5652         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5653         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5654         .sk_alloc_security =            selinux_sk_alloc_security,
5655         .sk_free_security =             selinux_sk_free_security,
5656         .sk_clone_security =            selinux_sk_clone_security,
5657         .sk_getsecid =                  selinux_sk_getsecid,
5658         .sock_graft =                   selinux_sock_graft,
5659         .inet_conn_request =            selinux_inet_conn_request,
5660         .inet_csk_clone =               selinux_inet_csk_clone,
5661         .inet_conn_established =        selinux_inet_conn_established,
5662         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
5663         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
5664         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
5665         .req_classify_flow =            selinux_req_classify_flow,
5666         .tun_dev_create =               selinux_tun_dev_create,
5667         .tun_dev_post_create =          selinux_tun_dev_post_create,
5668         .tun_dev_attach =               selinux_tun_dev_attach,
5669
5670 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5671         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5672         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5673         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5674         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5675         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5676         .xfrm_state_free_security =     selinux_xfrm_state_free,
5677         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5678         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5679         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5680         .xfrm_decode_session =          selinux_xfrm_decode_session,
5681 #endif
5682
5683 #ifdef CONFIG_KEYS
5684         .key_alloc =                    selinux_key_alloc,
5685         .key_free =                     selinux_key_free,
5686         .key_permission =               selinux_key_permission,
5687         .key_getsecurity =              selinux_key_getsecurity,
5688 #endif
5689
5690 #ifdef CONFIG_AUDIT
5691         .audit_rule_init =              selinux_audit_rule_init,
5692         .audit_rule_known =             selinux_audit_rule_known,
5693         .audit_rule_match =             selinux_audit_rule_match,
5694         .audit_rule_free =              selinux_audit_rule_free,
5695 #endif
5696 };
5697
5698 static __init int selinux_init(void)
5699 {
5700         if (!security_module_enable(&selinux_ops)) {
5701                 selinux_enabled = 0;
5702                 return 0;
5703         }
5704
5705         if (!selinux_enabled) {
5706                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5707                 return 0;
5708         }
5709
5710         printk(KERN_INFO "SELinux:  Initializing.\n");
5711
5712         /* Set the security state for the initial task. */
5713         cred_init_security();
5714
5715         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5716
5717         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5718                                             sizeof(struct inode_security_struct),
5719                                             0, SLAB_PANIC, NULL);
5720         avc_init();
5721
5722         if (register_security(&selinux_ops))
5723                 panic("SELinux: Unable to register with kernel.\n");
5724
5725         if (selinux_enforcing)
5726                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5727         else
5728                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5729
5730         return 0;
5731 }
5732
5733 static void delayed_superblock_init(struct super_block *sb, void *unused)
5734 {
5735         superblock_doinit(sb, NULL);
5736 }
5737
5738 void selinux_complete_init(void)
5739 {
5740         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5741
5742         /* Set up any superblocks initialized prior to the policy load. */
5743         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5744         iterate_supers(delayed_superblock_init, NULL);
5745 }
5746
5747 /* SELinux requires early initialization in order to label
5748    all processes and objects when they are created. */
5749 security_initcall(selinux_init);
5750
5751 #if defined(CONFIG_NETFILTER)
5752
5753 static struct nf_hook_ops selinux_ipv4_ops[] = {
5754         {
5755                 .hook =         selinux_ipv4_postroute,
5756                 .owner =        THIS_MODULE,
5757                 .pf =           PF_INET,
5758                 .hooknum =      NF_INET_POST_ROUTING,
5759                 .priority =     NF_IP_PRI_SELINUX_LAST,
5760         },
5761         {
5762                 .hook =         selinux_ipv4_forward,
5763                 .owner =        THIS_MODULE,
5764                 .pf =           PF_INET,
5765                 .hooknum =      NF_INET_FORWARD,
5766                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5767         },
5768         {
5769                 .hook =         selinux_ipv4_output,
5770                 .owner =        THIS_MODULE,
5771                 .pf =           PF_INET,
5772                 .hooknum =      NF_INET_LOCAL_OUT,
5773                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5774         }
5775 };
5776
5777 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5778
5779 static struct nf_hook_ops selinux_ipv6_ops[] = {
5780         {
5781                 .hook =         selinux_ipv6_postroute,
5782                 .owner =        THIS_MODULE,
5783                 .pf =           PF_INET6,
5784                 .hooknum =      NF_INET_POST_ROUTING,
5785                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5786         },
5787         {
5788                 .hook =         selinux_ipv6_forward,
5789                 .owner =        THIS_MODULE,
5790                 .pf =           PF_INET6,
5791                 .hooknum =      NF_INET_FORWARD,
5792                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5793         }
5794 };
5795
5796 #endif  /* IPV6 */
5797
5798 static int __init selinux_nf_ip_init(void)
5799 {
5800         int err = 0;
5801
5802         if (!selinux_enabled)
5803                 goto out;
5804
5805         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5806
5807         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5808         if (err)
5809                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5810
5811 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5812         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5813         if (err)
5814                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5815 #endif  /* IPV6 */
5816
5817 out:
5818         return err;
5819 }
5820
5821 __initcall(selinux_nf_ip_init);
5822
5823 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5824 static void selinux_nf_ip_exit(void)
5825 {
5826         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5827
5828         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5829 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5830         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5831 #endif  /* IPV6 */
5832 }
5833 #endif
5834
5835 #else /* CONFIG_NETFILTER */
5836
5837 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5838 #define selinux_nf_ip_exit()
5839 #endif
5840
5841 #endif /* CONFIG_NETFILTER */
5842
5843 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5844 static int selinux_disabled;
5845
5846 int selinux_disable(void)
5847 {
5848         if (ss_initialized) {
5849                 /* Not permitted after initial policy load. */
5850                 return -EINVAL;
5851         }
5852
5853         if (selinux_disabled) {
5854                 /* Only do this once. */
5855                 return -EINVAL;
5856         }
5857
5858         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5859
5860         selinux_disabled = 1;
5861         selinux_enabled = 0;
5862
5863         reset_security_ops();
5864
5865         /* Try to destroy the avc node cache */
5866         avc_disable();
5867
5868         /* Unregister netfilter hooks. */
5869         selinux_nf_ip_exit();
5870
5871         /* Unregister selinuxfs. */
5872         exit_sel_fs();
5873
5874         return 0;
5875 }
5876 #endif