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.moore@hp.com>
  18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  19  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
  20  *
  21  *      This program is free software; you can redistribute it and/or modify
  22  *      it under the terms of the GNU General Public License version 2,
  23  *      as published by the Free Software Foundation.
  24  */
  25
  26 #include <linux/init.h>
  27 #include <linux/kd.h>
  28 #include <linux/kernel.h>
  29 #include <linux/tracehook.h>
  30 #include <linux/errno.h>
  31 #include <linux/ext2_fs.h>
  32 #include <linux/sched.h>
  33 #include <linux/security.h>
  34 #include <linux/xattr.h>
  35 #include <linux/capability.h>
  36 #include <linux/unistd.h>
  37 #include <linux/mm.h>
  38 #include <linux/mman.h>
  39 #include <linux/slab.h>
  40 #include <linux/pagemap.h>
  41 #include <linux/proc_fs.h>
  42 #include <linux/swap.h>
  43 #include <linux/spinlock.h>
  44 #include <linux/syscalls.h>
  45 #include <linux/dcache.h>
  46 #include <linux/file.h>
  47 #include <linux/fdtable.h>
  48 #include <linux/namei.h>
  49 #include <linux/mount.h>
  50 #include <linux/netfilter_ipv4.h>
  51 #include <linux/netfilter_ipv6.h>
  52 #include <linux/tty.h>
  53 #include <net/icmp.h>
  54 #include <net/ip.h>             /* for local_port_range[] */
  55 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  56 #include <net/net_namespace.h>
  57 #include <net/netlabel.h>
  58 #include <linux/uaccess.h>
  59 #include <asm/ioctls.h>
  60 #include <asm/atomic.h>
  61 #include <linux/bitops.h>
  62 #include <linux/interrupt.h>
  63 #include <linux/netdevice.h>    /* for network interface checks */
  64 #include <linux/netlink.h>
  65 #include <linux/tcp.h>
  66 #include <linux/udp.h>
  67 #include <linux/dccp.h>
  68 #include <linux/quota.h>
  69 #include <linux/un.h>           /* for Unix socket types */
  70 #include <net/af_unix.h>        /* for Unix socket types */
  71 #include <linux/parser.h>
  72 #include <linux/nfs_mount.h>
  73 #include <net/ipv6.h>
  74 #include <linux/hugetlb.h>
  75 #include <linux/personality.h>
  76 #include <linux/audit.h>
  77 #include <linux/string.h>
  78 #include <linux/selinux.h>
  79 #include <linux/mutex.h>
  80 #include <linux/posix-timers.h>
  81 #include <linux/syslog.h>
  82 #include <linux/user_namespace.h>
  83
  84 #include "avc.h"
  85 #include "objsec.h"
  86 #include "netif.h"
  87 #include "netnode.h"
  88 #include "netport.h"
  89 #include "xfrm.h"
  90 #include "netlabel.h"
  91 #include "audit.h"
  92
  93 #define NUM_SEL_MNT_OPTS 5
  94
  95 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
  96 extern struct security_operations *security_ops;
  97
  98 /* SECMARK reference count */
  99 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 100
 101 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 102 int selinux_enforcing;
 103
 104 static int __init enforcing_setup(char *str)
 105 {
 106         unsigned long enforcing;
 107         if (!strict_strtoul(str, 0, &enforcing))
 108                 selinux_enforcing = enforcing ? 1 : 0;
 109         return 1;
 110 }
 111 __setup("enforcing=", enforcing_setup);
 112 #endif
 113
 114 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 115 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
 116
 117 static int __init selinux_enabled_setup(char *str)
 118 {
 119         unsigned long enabled;
 120         if (!strict_strtoul(str, 0, &enabled))
 121                 selinux_enabled = enabled ? 1 : 0;
 122         return 1;
 123 }
 124 __setup("selinux=", selinux_enabled_setup);
 125 #else
 126 int selinux_enabled = 1;
 127 #endif
 128
 129 static struct kmem_cache *sel_inode_cache;
 130
 131 /**
 132  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 133  *
 134  * Description:
 135  * This function checks the SECMARK reference counter to see if any SECMARK
 136  * targets are currently configured, if the reference counter is greater than
 137  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 138  * enabled, false (0) if SECMARK is disabled.
 139  *
 140  */
 141 static int selinux_secmark_enabled(void)
 142 {
 143         return (atomic_read(&selinux_secmark_refcount) > 0);
 144 }
 145
 146 /*
 147  * initialise the security for the init task
 148  */
 149 static void cred_init_security(void)
 150 {
 151         struct cred *cred = (struct cred *) current->real_cred;
 152         struct task_security_struct *tsec;
 153
 154         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 155         if (!tsec)
 156                 panic("SELinux:  Failed to initialize initial task.\n");
 157
 158         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 159         cred->security = tsec;
 160 }
 161
 162 /*
 163  * get the security ID of a set of credentials
 164  */
 165 static inline u32 cred_sid(const struct cred *cred)
 166 {
 167         const struct task_security_struct *tsec;
 168
 169         tsec = cred->security;
 170         return tsec->sid;
 171 }
 172
 173 /*
 174  * get the objective security ID of a task
 175  */
 176 static inline u32 task_sid(const struct task_struct *task)
 177 {
 178         u32 sid;
 179
 180         rcu_read_lock();
 181         sid = cred_sid(__task_cred(task));
 182         rcu_read_unlock();
 183         return sid;
 184 }
 185
 186 /*
 187  * get the subjective security ID of the current task
 188  */
 189 static inline u32 current_sid(void)
 190 {
 191         const struct task_security_struct *tsec = current_security();
 192
 193         return tsec->sid;
 194 }
 195
 196 /* Allocate and free functions for each kind of security blob. */
 197
 198 static int inode_alloc_security(struct inode *inode)
 199 {
 200         struct inode_security_struct *isec;
 201         u32 sid = current_sid();
 202
 203         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
 204         if (!isec)
 205                 return -ENOMEM;
 206
 207         mutex_init(&isec->lock);
 208         INIT_LIST_HEAD(&isec->list);
 209         isec->inode = inode;
 210         isec->sid = SECINITSID_UNLABELED;
 211         isec->sclass = SECCLASS_FILE;
 212         isec->task_sid = sid;
 213         inode->i_security = isec;
 214
 215         return 0;
 216 }
 217
 218 static void inode_free_security(struct inode *inode)
 219 {
 220         struct inode_security_struct *isec = inode->i_security;
 221         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 222
 223         spin_lock(&sbsec->isec_lock);
 224         if (!list_empty(&isec->list))
 225                 list_del_init(&isec->list);
 226         spin_unlock(&sbsec->isec_lock);
 227
 228         inode->i_security = NULL;
 229         kmem_cache_free(sel_inode_cache, isec);
 230 }
 231
 232 static int file_alloc_security(struct file *file)
 233 {
 234         struct file_security_struct *fsec;
 235         u32 sid = current_sid();
 236
 237         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
 238         if (!fsec)
 239                 return -ENOMEM;
 240
 241         fsec->sid = sid;
 242         fsec->fown_sid = sid;
 243         file->f_security = fsec;
 244
 245         return 0;
 246 }
 247
 248 static void file_free_security(struct file *file)
 249 {
 250         struct file_security_struct *fsec = file->f_security;
 251         file->f_security = NULL;
 252         kfree(fsec);
 253 }
 254
 255 static int superblock_alloc_security(struct super_block *sb)
 256 {
 257         struct superblock_security_struct *sbsec;
 258
 259         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 260         if (!sbsec)
 261                 return -ENOMEM;
 262
 263         mutex_init(&sbsec->lock);
 264         INIT_LIST_HEAD(&sbsec->isec_head);
 265         spin_lock_init(&sbsec->isec_lock);
 266         sbsec->sb = sb;
 267         sbsec->sid = SECINITSID_UNLABELED;
 268         sbsec->def_sid = SECINITSID_FILE;
 269         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 270         sb->s_security = sbsec;
 271
 272         return 0;
 273 }
 274
 275 static void superblock_free_security(struct super_block *sb)
 276 {
 277         struct superblock_security_struct *sbsec = sb->s_security;
 278         sb->s_security = NULL;
 279         kfree(sbsec);
 280 }
 281
 282 /* The security server must be initialized before
 283    any labeling or access decisions can be provided. */
 284 extern int ss_initialized;
 285
 286 /* The file system's label must be initialized prior to use. */
 287
 288 static const char *labeling_behaviors[6] = {
 289         "uses xattr",
 290         "uses transition SIDs",
 291         "uses task SIDs",
 292         "uses genfs_contexts",
 293         "not configured for labeling",
 294         "uses mountpoint labeling",
 295 };
 296
 297 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 298
 299 static inline int inode_doinit(struct inode *inode)
 300 {
 301         return inode_doinit_with_dentry(inode, NULL);
 302 }
 303
 304 enum {
 305         Opt_error = -1,
 306         Opt_context = 1,
 307         Opt_fscontext = 2,
 308         Opt_defcontext = 3,
 309         Opt_rootcontext = 4,
 310         Opt_labelsupport = 5,
 311 };
 312
 313 static const match_table_t tokens = {
 314         {Opt_context, CONTEXT_STR "%s"},
 315         {Opt_fscontext, FSCONTEXT_STR "%s"},
 316         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 317         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 318         {Opt_labelsupport, LABELSUPP_STR},
 319         {Opt_error, NULL},
 320 };
 321
 322 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 323
 324 static int may_context_mount_sb_relabel(u32 sid,
 325                         struct superblock_security_struct *sbsec,
 326                         const struct cred *cred)
 327 {
 328         const struct task_security_struct *tsec = cred->security;
 329         int rc;
 330
 331         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 332                           FILESYSTEM__RELABELFROM, NULL);
 333         if (rc)
 334                 return rc;
 335
 336         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 337                           FILESYSTEM__RELABELTO, NULL);
 338         return rc;
 339 }
 340
 341 static int may_context_mount_inode_relabel(u32 sid,
 342                         struct superblock_security_struct *sbsec,
 343                         const struct cred *cred)
 344 {
 345         const struct task_security_struct *tsec = cred->security;
 346         int rc;
 347         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 348                           FILESYSTEM__RELABELFROM, NULL);
 349         if (rc)
 350                 return rc;
 351
 352         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 353                           FILESYSTEM__ASSOCIATE, NULL);
 354         return rc;
 355 }
 356
 357 static int sb_finish_set_opts(struct super_block *sb)
 358 {
 359         struct superblock_security_struct *sbsec = sb->s_security;
 360         struct dentry *root = sb->s_root;
 361         struct inode *root_inode = root->d_inode;
 362         int rc = 0;
 363
 364         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 365                 /* Make sure that the xattr handler exists and that no
 366                    error other than -ENODATA is returned by getxattr on
 367                    the root directory.  -ENODATA is ok, as this may be
 368                    the first boot of the SELinux kernel before we have
 369                    assigned xattr values to the filesystem. */
 370                 if (!root_inode->i_op->getxattr) {
 371                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
 372                                "xattr support\n", sb->s_id, sb->s_type->name);
 373                         rc = -EOPNOTSUPP;
 374                         goto out;
 375                 }
 376                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
 377                 if (rc < 0 && rc != -ENODATA) {
 378                         if (rc == -EOPNOTSUPP)
 379                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 380                                        "%s) has no security xattr handler\n",
 381                                        sb->s_id, sb->s_type->name);
 382                         else
 383                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 384                                        "%s) getxattr errno %d\n", sb->s_id,
 385                                        sb->s_type->name, -rc);
 386                         goto out;
 387                 }
 388         }
 389
 390         sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
 391
 392         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 393                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
 394                        sb->s_id, sb->s_type->name);
 395         else
 396                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
 397                        sb->s_id, sb->s_type->name,
 398                        labeling_behaviors[sbsec->behavior-1]);
 399
 400         if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
 401             sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
 402             sbsec->behavior == SECURITY_FS_USE_NONE ||
 403             sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 404                 sbsec->flags &= ~SE_SBLABELSUPP;
 405
 406         /* Special handling for sysfs. Is genfs but also has setxattr handler*/
 407         if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
 408                 sbsec->flags |= SE_SBLABELSUPP;
 409
 410         /* Initialize the root inode. */
 411         rc = inode_doinit_with_dentry(root_inode, root);
 412
 413         /* Initialize any other inodes associated with the superblock, e.g.
 414            inodes created prior to initial policy load or inodes created
 415            during get_sb by a pseudo filesystem that directly
 416            populates itself. */
 417         spin_lock(&sbsec->isec_lock);
 418 next_inode:
 419         if (!list_empty(&sbsec->isec_head)) {
 420                 struct inode_security_struct *isec =
 421                                 list_entry(sbsec->isec_head.next,
 422                                            struct inode_security_struct, list);
 423                 struct inode *inode = isec->inode;
 424                 spin_unlock(&sbsec->isec_lock);
 425                 inode = igrab(inode);
 426                 if (inode) {
 427                         if (!IS_PRIVATE(inode))
 428                                 inode_doinit(inode);
 429                         iput(inode);
 430                 }
 431                 spin_lock(&sbsec->isec_lock);
 432                 list_del_init(&isec->list);
 433                 goto next_inode;
 434         }
 435         spin_unlock(&sbsec->isec_lock);
 436 out:
 437         return rc;
 438 }
 439
 440 /*
 441  * This function should allow an FS to ask what it's mount security
 442  * options were so it can use those later for submounts, displaying
 443  * mount options, or whatever.
 444  */
 445 static int selinux_get_mnt_opts(const struct super_block *sb,
 446                                 struct security_mnt_opts *opts)
 447 {
 448         int rc = 0, i;
 449         struct superblock_security_struct *sbsec = sb->s_security;
 450         char *context = NULL;
 451         u32 len;
 452         char tmp;
 453
 454         security_init_mnt_opts(opts);
 455
 456         if (!(sbsec->flags & SE_SBINITIALIZED))
 457                 return -EINVAL;
 458
 459         if (!ss_initialized)
 460                 return -EINVAL;
 461
 462         tmp = sbsec->flags & SE_MNTMASK;
 463         /* count the number of mount options for this sb */
 464         for (i = 0; i < 8; i++) {
 465                 if (tmp & 0x01)
 466                         opts->num_mnt_opts++;
 467                 tmp >>= 1;
 468         }
 469         /* Check if the Label support flag is set */
 470         if (sbsec->flags & SE_SBLABELSUPP)
 471                 opts->num_mnt_opts++;
 472
 473         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 474         if (!opts->mnt_opts) {
 475                 rc = -ENOMEM;
 476                 goto out_free;
 477         }
 478
 479         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 480         if (!opts->mnt_opts_flags) {
 481                 rc = -ENOMEM;
 482                 goto out_free;
 483         }
 484
 485         i = 0;
 486         if (sbsec->flags & FSCONTEXT_MNT) {
 487                 rc = security_sid_to_context(sbsec->sid, &context, &len);
 488                 if (rc)
 489                         goto out_free;
 490                 opts->mnt_opts[i] = context;
 491                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 492         }
 493         if (sbsec->flags & CONTEXT_MNT) {
 494                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
 495                 if (rc)
 496                         goto out_free;
 497                 opts->mnt_opts[i] = context;
 498                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 499         }
 500         if (sbsec->flags & DEFCONTEXT_MNT) {
 501                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
 502                 if (rc)
 503                         goto out_free;
 504                 opts->mnt_opts[i] = context;
 505                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 506         }
 507         if (sbsec->flags & ROOTCONTEXT_MNT) {
 508                 struct inode *root = sbsec->sb->s_root->d_inode;
 509                 struct inode_security_struct *isec = root->i_security;
 510
 511                 rc = security_sid_to_context(isec->sid, &context, &len);
 512                 if (rc)
 513                         goto out_free;
 514                 opts->mnt_opts[i] = context;
 515                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 516         }
 517         if (sbsec->flags & SE_SBLABELSUPP) {
 518                 opts->mnt_opts[i] = NULL;
 519                 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
 520         }
 521
 522         BUG_ON(i != opts->num_mnt_opts);
 523
 524         return 0;
 525
 526 out_free:
 527         security_free_mnt_opts(opts);
 528         return rc;
 529 }
 530
 531 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 532                       u32 old_sid, u32 new_sid)
 533 {
 534         char mnt_flags = sbsec->flags & SE_MNTMASK;
 535
 536         /* check if the old mount command had the same options */
 537         if (sbsec->flags & SE_SBINITIALIZED)
 538                 if (!(sbsec->flags & flag) ||
 539                     (old_sid != new_sid))
 540                         return 1;
 541
 542         /* check if we were passed the same options twice,
 543          * aka someone passed context=a,context=b
 544          */
 545         if (!(sbsec->flags & SE_SBINITIALIZED))
 546                 if (mnt_flags & flag)
 547                         return 1;
 548         return 0;
 549 }
 550
 551 /*
 552  * Allow filesystems with binary mount data to explicitly set mount point
 553  * labeling information.
 554  */
 555 static int selinux_set_mnt_opts(struct super_block *sb,
 556                                 struct security_mnt_opts *opts)
 557 {
 558         const struct cred *cred = current_cred();
 559         int rc = 0, i;
 560         struct superblock_security_struct *sbsec = sb->s_security;
 561         const char *name = sb->s_type->name;
 562         struct inode *inode = sbsec->sb->s_root->d_inode;
 563         struct inode_security_struct *root_isec = inode->i_security;
 564         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 565         u32 defcontext_sid = 0;
 566         char **mount_options = opts->mnt_opts;
 567         int *flags = opts->mnt_opts_flags;
 568         int num_opts = opts->num_mnt_opts;
 569
 570         mutex_lock(&sbsec->lock);
 571
 572         if (!ss_initialized) {
 573                 if (!num_opts) {
 574                         /* Defer initialization until selinux_complete_init,
 575                            after the initial policy is loaded and the security
 576                            server is ready to handle calls. */
 577                         goto out;
 578                 }
 579                 rc = -EINVAL;
 580                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
 581                         "before the security server is initialized\n");
 582                 goto out;
 583         }
 584
 585         /*
 586          * Binary mount data FS will come through this function twice.  Once
 587          * from an explicit call and once from the generic calls from the vfs.
 588          * Since the generic VFS calls will not contain any security mount data
 589          * we need to skip the double mount verification.
 590          *
 591          * This does open a hole in which we will not notice if the first
 592          * mount using this sb set explict options and a second mount using
 593          * this sb does not set any security options.  (The first options
 594          * will be used for both mounts)
 595          */
 596         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 597             && (num_opts == 0))
 598                 goto out;
 599
 600         /*
 601          * parse the mount options, check if they are valid sids.
 602          * also check if someone is trying to mount the same sb more
 603          * than once with different security options.
 604          */
 605         for (i = 0; i < num_opts; i++) {
 606                 u32 sid;
 607
 608                 if (flags[i] == SE_SBLABELSUPP)
 609                         continue;
 610                 rc = security_context_to_sid(mount_options[i],
 611                                              strlen(mount_options[i]), &sid);
 612                 if (rc) {
 613                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 614                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 615                                mount_options[i], sb->s_id, name, rc);
 616                         goto out;
 617                 }
 618                 switch (flags[i]) {
 619                 case FSCONTEXT_MNT:
 620                         fscontext_sid = sid;
 621
 622                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 623                                         fscontext_sid))
 624                                 goto out_double_mount;
 625
 626                         sbsec->flags |= FSCONTEXT_MNT;
 627                         break;
 628                 case CONTEXT_MNT:
 629                         context_sid = sid;
 630
 631                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 632                                         context_sid))
 633                                 goto out_double_mount;
 634
 635                         sbsec->flags |= CONTEXT_MNT;
 636                         break;
 637                 case ROOTCONTEXT_MNT:
 638                         rootcontext_sid = sid;
 639
 640                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 641                                         rootcontext_sid))
 642                                 goto out_double_mount;
 643
 644                         sbsec->flags |= ROOTCONTEXT_MNT;
 645
 646                         break;
 647                 case DEFCONTEXT_MNT:
 648                         defcontext_sid = sid;
 649
 650                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 651                                         defcontext_sid))
 652                                 goto out_double_mount;
 653
 654                         sbsec->flags |= DEFCONTEXT_MNT;
 655
 656                         break;
 657                 default:
 658                         rc = -EINVAL;
 659                         goto out;
 660                 }
 661         }
 662
 663         if (sbsec->flags & SE_SBINITIALIZED) {
 664                 /* previously mounted with options, but not on this attempt? */
 665                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
 666                         goto out_double_mount;
 667                 rc = 0;
 668                 goto out;
 669         }
 670
 671         if (strcmp(sb->s_type->name, "proc") == 0)
 672                 sbsec->flags |= SE_SBPROC;
 673
 674         /* Determine the labeling behavior to use for this filesystem type. */
 675         rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
 676         if (rc) {
 677                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
 678                        __func__, sb->s_type->name, rc);
 679                 goto out;
 680         }
 681
 682         /* sets the context of the superblock for the fs being mounted. */
 683         if (fscontext_sid) {
 684                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 685                 if (rc)
 686                         goto out;
 687
 688                 sbsec->sid = fscontext_sid;
 689         }
 690
 691         /*
 692          * Switch to using mount point labeling behavior.
 693          * sets the label used on all file below the mountpoint, and will set
 694          * the superblock context if not already set.
 695          */
 696         if (context_sid) {
 697                 if (!fscontext_sid) {
 698                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 699                                                           cred);
 700                         if (rc)
 701                                 goto out;
 702                         sbsec->sid = context_sid;
 703                 } else {
 704                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 705                                                              cred);
 706                         if (rc)
 707                                 goto out;
 708                 }
 709                 if (!rootcontext_sid)
 710                         rootcontext_sid = context_sid;
 711
 712                 sbsec->mntpoint_sid = context_sid;
 713                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 714         }
 715
 716         if (rootcontext_sid) {
 717                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 718                                                      cred);
 719                 if (rc)
 720                         goto out;
 721
 722                 root_isec->sid = rootcontext_sid;
 723                 root_isec->initialized = 1;
 724         }
 725
 726         if (defcontext_sid) {
 727                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
 728                         rc = -EINVAL;
 729                         printk(KERN_WARNING "SELinux: defcontext option is "
 730                                "invalid for this filesystem type\n");
 731                         goto out;
 732                 }
 733
 734                 if (defcontext_sid != sbsec->def_sid) {
 735                         rc = may_context_mount_inode_relabel(defcontext_sid,
 736                                                              sbsec, cred);
 737                         if (rc)
 738                                 goto out;
 739                 }
 740
 741                 sbsec->def_sid = defcontext_sid;
 742         }
 743
 744         rc = sb_finish_set_opts(sb);
 745 out:
 746         mutex_unlock(&sbsec->lock);
 747         return rc;
 748 out_double_mount:
 749         rc = -EINVAL;
 750         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 751                "security settings for (dev %s, type %s)\n", sb->s_id, name);
 752         goto out;
 753 }
 754
 755 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 756                                         struct super_block *newsb)
 757 {
 758         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 759         struct superblock_security_struct *newsbsec = newsb->s_security;
 760
 761         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 762         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 763         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 764
 765         /*
 766          * if the parent was able to be mounted it clearly had no special lsm
 767          * mount options.  thus we can safely deal with this superblock later
 768          */
 769         if (!ss_initialized)
 770                 return;
 771
 772         /* how can we clone if the old one wasn't set up?? */
 773         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 774
 775         /* if fs is reusing a sb, just let its options stand... */
 776         if (newsbsec->flags & SE_SBINITIALIZED)
 777                 return;
 778
 779         mutex_lock(&newsbsec->lock);
 780
 781         newsbsec->flags = oldsbsec->flags;
 782
 783         newsbsec->sid = oldsbsec->sid;
 784         newsbsec->def_sid = oldsbsec->def_sid;
 785         newsbsec->behavior = oldsbsec->behavior;
 786
 787         if (set_context) {
 788                 u32 sid = oldsbsec->mntpoint_sid;
 789
 790                 if (!set_fscontext)
 791                         newsbsec->sid = sid;
 792                 if (!set_rootcontext) {
 793                         struct inode *newinode = newsb->s_root->d_inode;
 794                         struct inode_security_struct *newisec = newinode->i_security;
 795                         newisec->sid = sid;
 796                 }
 797                 newsbsec->mntpoint_sid = sid;
 798         }
 799         if (set_rootcontext) {
 800                 const struct inode *oldinode = oldsb->s_root->d_inode;
 801                 const struct inode_security_struct *oldisec = oldinode->i_security;
 802                 struct inode *newinode = newsb->s_root->d_inode;
 803                 struct inode_security_struct *newisec = newinode->i_security;
 804
 805                 newisec->sid = oldisec->sid;
 806         }
 807
 808         sb_finish_set_opts(newsb);
 809         mutex_unlock(&newsbsec->lock);
 810 }
 811
 812 static int selinux_parse_opts_str(char *options,
 813                                   struct security_mnt_opts *opts)
 814 {
 815         char *p;
 816         char *context = NULL, *defcontext = NULL;
 817         char *fscontext = NULL, *rootcontext = NULL;
 818         int rc, num_mnt_opts = 0;
 819
 820         opts->num_mnt_opts = 0;
 821
 822         /* Standard string-based options. */
 823         while ((p = strsep(&options, "|")) != NULL) {
 824                 int token;
 825                 substring_t args[MAX_OPT_ARGS];
 826
 827                 if (!*p)
 828                         continue;
 829
 830                 token = match_token(p, tokens, args);
 831
 832                 switch (token) {
 833                 case Opt_context:
 834                         if (context || defcontext) {
 835                                 rc = -EINVAL;
 836                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 837                                 goto out_err;
 838                         }
 839                         context = match_strdup(&args[0]);
 840                         if (!context) {
 841                                 rc = -ENOMEM;
 842                                 goto out_err;
 843                         }
 844                         break;
 845
 846                 case Opt_fscontext:
 847                         if (fscontext) {
 848                                 rc = -EINVAL;
 849                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 850                                 goto out_err;
 851                         }
 852                         fscontext = match_strdup(&args[0]);
 853                         if (!fscontext) {
 854                                 rc = -ENOMEM;
 855                                 goto out_err;
 856                         }
 857                         break;
 858
 859                 case Opt_rootcontext:
 860                         if (rootcontext) {
 861                                 rc = -EINVAL;
 862                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 863                                 goto out_err;
 864                         }
 865                         rootcontext = match_strdup(&args[0]);
 866                         if (!rootcontext) {
 867                                 rc = -ENOMEM;
 868                                 goto out_err;
 869                         }
 870                         break;
 871
 872                 case Opt_defcontext:
 873                         if (context || defcontext) {
 874                                 rc = -EINVAL;
 875                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 876                                 goto out_err;
 877                         }
 878                         defcontext = match_strdup(&args[0]);
 879                         if (!defcontext) {
 880                                 rc = -ENOMEM;
 881                                 goto out_err;
 882                         }
 883                         break;
 884                 case Opt_labelsupport:
 885                         break;
 886                 default:
 887                         rc = -EINVAL;
 888                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
 889                         goto out_err;
 890
 891                 }
 892         }
 893
 894         rc = -ENOMEM;
 895         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
 896         if (!opts->mnt_opts)
 897                 goto out_err;
 898
 899         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
 900         if (!opts->mnt_opts_flags) {
 901                 kfree(opts->mnt_opts);
 902                 goto out_err;
 903         }
 904
 905         if (fscontext) {
 906                 opts->mnt_opts[num_mnt_opts] = fscontext;
 907                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
 908         }
 909         if (context) {
 910                 opts->mnt_opts[num_mnt_opts] = context;
 911                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
 912         }
 913         if (rootcontext) {
 914                 opts->mnt_opts[num_mnt_opts] = rootcontext;
 915                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
 916         }
 917         if (defcontext) {
 918                 opts->mnt_opts[num_mnt_opts] = defcontext;
 919                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
 920         }
 921
 922         opts->num_mnt_opts = num_mnt_opts;
 923         return 0;
 924
 925 out_err:
 926         kfree(context);
 927         kfree(defcontext);
 928         kfree(fscontext);
 929         kfree(rootcontext);
 930         return rc;
 931 }
 932 /*
 933  * string mount options parsing and call set the sbsec
 934  */
 935 static int superblock_doinit(struct super_block *sb, void *data)
 936 {
 937         int rc = 0;
 938         char *options = data;
 939         struct security_mnt_opts opts;
 940
 941         security_init_mnt_opts(&opts);
 942
 943         if (!data)
 944                 goto out;
 945
 946         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
 947
 948         rc = selinux_parse_opts_str(options, &opts);
 949         if (rc)
 950                 goto out_err;
 951
 952 out:
 953         rc = selinux_set_mnt_opts(sb, &opts);
 954
 955 out_err:
 956         security_free_mnt_opts(&opts);
 957         return rc;
 958 }
 959
 960 static void selinux_write_opts(struct seq_file *m,
 961                                struct security_mnt_opts *opts)
 962 {
 963         int i;
 964         char *prefix;
 965
 966         for (i = 0; i < opts->num_mnt_opts; i++) {
 967                 char *has_comma;
 968
 969                 if (opts->mnt_opts[i])
 970                         has_comma = strchr(opts->mnt_opts[i], ',');
 971                 else
 972                         has_comma = NULL;
 973
 974                 switch (opts->mnt_opts_flags[i]) {
 975                 case CONTEXT_MNT:
 976                         prefix = CONTEXT_STR;
 977                         break;
 978                 case FSCONTEXT_MNT:
 979                         prefix = FSCONTEXT_STR;
 980                         break;
 981                 case ROOTCONTEXT_MNT:
 982                         prefix = ROOTCONTEXT_STR;
 983                         break;
 984                 case DEFCONTEXT_MNT:
 985                         prefix = DEFCONTEXT_STR;
 986                         break;
 987                 case SE_SBLABELSUPP:
 988                         seq_putc(m, ',');
 989                         seq_puts(m, LABELSUPP_STR);
 990                         continue;
 991                 default:
 992                         BUG();
 993                 };
 994                 /* we need a comma before each option */
 995                 seq_putc(m, ',');
 996                 seq_puts(m, prefix);
 997                 if (has_comma)
 998                         seq_putc(m, '\"');
 999                 seq_puts(m, opts->mnt_opts[i]);
1000                 if (has_comma)
1001                         seq_putc(m, '\"');
1002         }
1003 }
1004
1005 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1006 {
1007         struct security_mnt_opts opts;
1008         int rc;
1009
1010         rc = selinux_get_mnt_opts(sb, &opts);
1011         if (rc) {
1012                 /* before policy load we may get EINVAL, don't show anything */
1013                 if (rc == -EINVAL)
1014                         rc = 0;
1015                 return rc;
1016         }
1017
1018         selinux_write_opts(m, &opts);
1019
1020         security_free_mnt_opts(&opts);
1021
1022         return rc;
1023 }
1024
1025 static inline u16 inode_mode_to_security_class(umode_t mode)
1026 {
1027         switch (mode & S_IFMT) {
1028         case S_IFSOCK:
1029                 return SECCLASS_SOCK_FILE;
1030         case S_IFLNK:
1031                 return SECCLASS_LNK_FILE;
1032         case S_IFREG:
1033                 return SECCLASS_FILE;
1034         case S_IFBLK:
1035                 return SECCLASS_BLK_FILE;
1036         case S_IFDIR:
1037                 return SECCLASS_DIR;
1038         case S_IFCHR:
1039                 return SECCLASS_CHR_FILE;
1040         case S_IFIFO:
1041                 return SECCLASS_FIFO_FILE;
1042
1043         }
1044
1045         return SECCLASS_FILE;
1046 }
1047
1048 static inline int default_protocol_stream(int protocol)
1049 {
1050         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1051 }
1052
1053 static inline int default_protocol_dgram(int protocol)
1054 {
1055         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1056 }
1057
1058 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1059 {
1060         switch (family) {
1061         case PF_UNIX:
1062                 switch (type) {
1063                 case SOCK_STREAM:
1064                 case SOCK_SEQPACKET:
1065                         return SECCLASS_UNIX_STREAM_SOCKET;
1066                 case SOCK_DGRAM:
1067                         return SECCLASS_UNIX_DGRAM_SOCKET;
1068                 }
1069                 break;
1070         case PF_INET:
1071         case PF_INET6:
1072                 switch (type) {
1073                 case SOCK_STREAM:
1074                         if (default_protocol_stream(protocol))
1075                                 return SECCLASS_TCP_SOCKET;
1076                         else
1077                                 return SECCLASS_RAWIP_SOCKET;
1078                 case SOCK_DGRAM:
1079                         if (default_protocol_dgram(protocol))
1080                                 return SECCLASS_UDP_SOCKET;
1081                         else
1082                                 return SECCLASS_RAWIP_SOCKET;
1083                 case SOCK_DCCP:
1084                         return SECCLASS_DCCP_SOCKET;
1085                 default:
1086                         return SECCLASS_RAWIP_SOCKET;
1087                 }
1088                 break;
1089         case PF_NETLINK:
1090                 switch (protocol) {
1091                 case NETLINK_ROUTE:
1092                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1093                 case NETLINK_FIREWALL:
1094                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1095                 case NETLINK_INET_DIAG:
1096                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1097                 case NETLINK_NFLOG:
1098                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1099                 case NETLINK_XFRM:
1100                         return SECCLASS_NETLINK_XFRM_SOCKET;
1101                 case NETLINK_SELINUX:
1102                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1103                 case NETLINK_AUDIT:
1104                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1105                 case NETLINK_IP6_FW:
1106                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1107                 case NETLINK_DNRTMSG:
1108                         return SECCLASS_NETLINK_DNRT_SOCKET;
1109                 case NETLINK_KOBJECT_UEVENT:
1110                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1111                 default:
1112                         return SECCLASS_NETLINK_SOCKET;
1113                 }
1114         case PF_PACKET:
1115                 return SECCLASS_PACKET_SOCKET;
1116         case PF_KEY:
1117                 return SECCLASS_KEY_SOCKET;
1118         case PF_APPLETALK:
1119                 return SECCLASS_APPLETALK_SOCKET;
1120         }
1121
1122         return SECCLASS_SOCKET;
1123 }
1124
1125 #ifdef CONFIG_PROC_FS
1126 static int selinux_proc_get_sid(struct dentry *dentry,
1127                                 u16 tclass,
1128                                 u32 *sid)
1129 {
1130         int rc;
1131         char *buffer, *path;
1132
1133         buffer = (char *)__get_free_page(GFP_KERNEL);
1134         if (!buffer)
1135                 return -ENOMEM;
1136
1137         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1138         if (IS_ERR(path))
1139                 rc = PTR_ERR(path);
1140         else {
1141                 /* each process gets a /proc/PID/ entry. Strip off the
1142                  * PID part to get a valid selinux labeling.
1143                  * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1144                 while (path[1] >= '0' && path[1] <= '9') {
1145                         path[1] = '/';
1146                         path++;
1147                 }
1148                 rc = security_genfs_sid("proc", path, tclass, sid);
1149         }
1150         free_page((unsigned long)buffer);
1151         return rc;
1152 }
1153 #else
1154 static int selinux_proc_get_sid(struct dentry *dentry,
1155                                 u16 tclass,
1156                                 u32 *sid)
1157 {
1158         return -EINVAL;
1159 }
1160 #endif
1161
1162 /* The inode's security attributes must be initialized before first use. */
1163 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1164 {
1165         struct superblock_security_struct *sbsec = NULL;
1166         struct inode_security_struct *isec = inode->i_security;
1167         u32 sid;
1168         struct dentry *dentry;
1169 #define INITCONTEXTLEN 255
1170         char *context = NULL;
1171         unsigned len = 0;
1172         int rc = 0;
1173
1174         if (isec->initialized)
1175                 goto out;
1176
1177         mutex_lock(&isec->lock);
1178         if (isec->initialized)
1179                 goto out_unlock;
1180
1181         sbsec = inode->i_sb->s_security;
1182         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1183                 /* Defer initialization until selinux_complete_init,
1184                    after the initial policy is loaded and the security
1185                    server is ready to handle calls. */
1186                 spin_lock(&sbsec->isec_lock);
1187                 if (list_empty(&isec->list))
1188                         list_add(&isec->list, &sbsec->isec_head);
1189                 spin_unlock(&sbsec->isec_lock);
1190                 goto out_unlock;
1191         }
1192
1193         switch (sbsec->behavior) {
1194         case SECURITY_FS_USE_XATTR:
1195                 if (!inode->i_op->getxattr) {
1196                         isec->sid = sbsec->def_sid;
1197                         break;
1198                 }
1199
1200                 /* Need a dentry, since the xattr API requires one.
1201                    Life would be simpler if we could just pass the inode. */
1202                 if (opt_dentry) {
1203                         /* Called from d_instantiate or d_splice_alias. */
1204                         dentry = dget(opt_dentry);
1205                 } else {
1206                         /* Called from selinux_complete_init, try to find a dentry. */
1207                         dentry = d_find_alias(inode);
1208                 }
1209                 if (!dentry) {
1210                         /*
1211                          * this is can be hit on boot when a file is accessed
1212                          * before the policy is loaded.  When we load policy we
1213                          * may find inodes that have no dentry on the
1214                          * sbsec->isec_head list.  No reason to complain as these
1215                          * will get fixed up the next time we go through
1216                          * inode_doinit with a dentry, before these inodes could
1217                          * be used again by userspace.
1218                          */
1219                         goto out_unlock;
1220                 }
1221
1222                 len = INITCONTEXTLEN;
1223                 context = kmalloc(len+1, GFP_NOFS);
1224                 if (!context) {
1225                         rc = -ENOMEM;
1226                         dput(dentry);
1227                         goto out_unlock;
1228                 }
1229                 context[len] = '\0';
1230                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1231                                            context, len);
1232                 if (rc == -ERANGE) {
1233                         kfree(context);
1234
1235                         /* Need a larger buffer.  Query for the right size. */
1236                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1237                                                    NULL, 0);
1238                         if (rc < 0) {
1239                                 dput(dentry);
1240                                 goto out_unlock;
1241                         }
1242                         len = rc;
1243                         context = kmalloc(len+1, GFP_NOFS);
1244                         if (!context) {
1245                                 rc = -ENOMEM;
1246                                 dput(dentry);
1247                                 goto out_unlock;
1248                         }
1249                         context[len] = '\0';
1250                         rc = inode->i_op->getxattr(dentry,
1251                                                    XATTR_NAME_SELINUX,
1252                                                    context, len);
1253                 }
1254                 dput(dentry);
1255                 if (rc < 0) {
1256                         if (rc != -ENODATA) {
1257                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1258                                        "%d for dev=%s ino=%ld\n", __func__,
1259                                        -rc, inode->i_sb->s_id, inode->i_ino);
1260                                 kfree(context);
1261                                 goto out_unlock;
1262                         }
1263                         /* Map ENODATA to the default file SID */
1264                         sid = sbsec->def_sid;
1265                         rc = 0;
1266                 } else {
1267                         rc = security_context_to_sid_default(context, rc, &sid,
1268                                                              sbsec->def_sid,
1269                                                              GFP_NOFS);
1270                         if (rc) {
1271                                 char *dev = inode->i_sb->s_id;
1272                                 unsigned long ino = inode->i_ino;
1273
1274                                 if (rc == -EINVAL) {
1275                                         if (printk_ratelimit())
1276                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1277                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1278                                                         "filesystem in question.\n", ino, dev, context);
1279                                 } else {
1280                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1281                                                "returned %d for dev=%s ino=%ld\n",
1282                                                __func__, context, -rc, dev, ino);
1283                                 }
1284                                 kfree(context);
1285                                 /* Leave with the unlabeled SID */
1286                                 rc = 0;
1287                                 break;
1288                         }
1289                 }
1290                 kfree(context);
1291                 isec->sid = sid;
1292                 break;
1293         case SECURITY_FS_USE_TASK:
1294                 isec->sid = isec->task_sid;
1295                 break;
1296         case SECURITY_FS_USE_TRANS:
1297                 /* Default to the fs SID. */
1298                 isec->sid = sbsec->sid;
1299
1300                 /* Try to obtain a transition SID. */
1301                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1302                 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1303                                              isec->sclass, NULL, &sid);
1304                 if (rc)
1305                         goto out_unlock;
1306                 isec->sid = sid;
1307                 break;
1308         case SECURITY_FS_USE_MNTPOINT:
1309                 isec->sid = sbsec->mntpoint_sid;
1310                 break;
1311         default:
1312                 /* Default to the fs superblock SID. */
1313                 isec->sid = sbsec->sid;
1314
1315                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1316                         if (opt_dentry) {
1317                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1318                                 rc = selinux_proc_get_sid(opt_dentry,
1319                                                           isec->sclass,
1320                                                           &sid);
1321                                 if (rc)
1322                                         goto out_unlock;
1323                                 isec->sid = sid;
1324                         }
1325                 }
1326                 break;
1327         }
1328
1329         isec->initialized = 1;
1330
1331 out_unlock:
1332         mutex_unlock(&isec->lock);
1333 out:
1334         if (isec->sclass == SECCLASS_FILE)
1335                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1336         return rc;
1337 }
1338
1339 /* Convert a Linux signal to an access vector. */
1340 static inline u32 signal_to_av(int sig)
1341 {
1342         u32 perm = 0;
1343
1344         switch (sig) {
1345         case SIGCHLD:
1346                 /* Commonly granted from child to parent. */
1347                 perm = PROCESS__SIGCHLD;
1348                 break;
1349         case SIGKILL:
1350                 /* Cannot be caught or ignored */
1351                 perm = PROCESS__SIGKILL;
1352                 break;
1353         case SIGSTOP:
1354                 /* Cannot be caught or ignored */
1355                 perm = PROCESS__SIGSTOP;
1356                 break;
1357         default:
1358                 /* All other signals. */
1359                 perm = PROCESS__SIGNAL;
1360                 break;
1361         }
1362
1363         return perm;
1364 }
1365
1366 /*
1367  * Check permission between a pair of credentials
1368  * fork check, ptrace check, etc.
1369  */
1370 static int cred_has_perm(const struct cred *actor,
1371                          const struct cred *target,
1372                          u32 perms)
1373 {
1374         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1375
1376         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1377 }
1378
1379 /*
1380  * Check permission between a pair of tasks, e.g. signal checks,
1381  * fork check, ptrace check, etc.
1382  * tsk1 is the actor and tsk2 is the target
1383  * - this uses the default subjective creds of tsk1
1384  */
1385 static int task_has_perm(const struct task_struct *tsk1,
1386                          const struct task_struct *tsk2,
1387                          u32 perms)
1388 {
1389         const struct task_security_struct *__tsec1, *__tsec2;
1390         u32 sid1, sid2;
1391
1392         rcu_read_lock();
1393         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1394         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1395         rcu_read_unlock();
1396         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1397 }
1398
1399 /*
1400  * Check permission between current and another task, e.g. signal checks,
1401  * fork check, ptrace check, etc.
1402  * current is the actor and tsk2 is the target
1403  * - this uses current's subjective creds
1404  */
1405 static int current_has_perm(const struct task_struct *tsk,
1406                             u32 perms)
1407 {
1408         u32 sid, tsid;
1409
1410         sid = current_sid();
1411         tsid = task_sid(tsk);
1412         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1413 }
1414
1415 #if CAP_LAST_CAP > 63
1416 #error Fix SELinux to handle capabilities > 63.
1417 #endif
1418
1419 /* Check whether a task is allowed to use a capability. */
1420 static int task_has_capability(struct task_struct *tsk,
1421                                const struct cred *cred,
1422                                int cap, int audit)
1423 {
1424         struct common_audit_data ad;
1425         struct av_decision avd;
1426         u16 sclass;
1427         u32 sid = cred_sid(cred);
1428         u32 av = CAP_TO_MASK(cap);
1429         int rc;
1430
1431         COMMON_AUDIT_DATA_INIT(&ad, CAP);
1432         ad.tsk = tsk;
1433         ad.u.cap = cap;
1434
1435         switch (CAP_TO_INDEX(cap)) {
1436         case 0:
1437                 sclass = SECCLASS_CAPABILITY;
1438                 break;
1439         case 1:
1440                 sclass = SECCLASS_CAPABILITY2;
1441                 break;
1442         default:
1443                 printk(KERN_ERR
1444                        "SELinux:  out of range capability %d\n", cap);
1445                 BUG();
1446         }
1447
1448         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1449         if (audit == SECURITY_CAP_AUDIT) {
1450                 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1451                 if (rc2)
1452                         return rc2;
1453         }
1454         return rc;
1455 }
1456
1457 /* Check whether a task is allowed to use a system operation. */
1458 static int task_has_system(struct task_struct *tsk,
1459                            u32 perms)
1460 {
1461         u32 sid = task_sid(tsk);
1462
1463         return avc_has_perm(sid, SECINITSID_KERNEL,
1464                             SECCLASS_SYSTEM, perms, NULL);
1465 }
1466
1467 /* Check whether a task has a particular permission to an inode.
1468    The 'adp' parameter is optional and allows other audit
1469    data to be passed (e.g. the dentry). */
1470 static int inode_has_perm(const struct cred *cred,
1471                           struct inode *inode,
1472                           u32 perms,
1473                           struct common_audit_data *adp,
1474                           unsigned flags)
1475 {
1476         struct inode_security_struct *isec;
1477         struct common_audit_data ad;
1478         u32 sid;
1479
1480         validate_creds(cred);
1481
1482         if (unlikely(IS_PRIVATE(inode)))
1483                 return 0;
1484
1485         sid = cred_sid(cred);
1486         isec = inode->i_security;
1487
1488         if (!adp) {
1489                 adp = &ad;
1490                 COMMON_AUDIT_DATA_INIT(&ad, FS);
1491                 ad.u.fs.inode = inode;
1492         }
1493
1494         return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1495 }
1496
1497 /* Same as inode_has_perm, but pass explicit audit data containing
1498    the dentry to help the auditing code to more easily generate the
1499    pathname if needed. */
1500 static inline int dentry_has_perm(const struct cred *cred,
1501                                   struct vfsmount *mnt,
1502                                   struct dentry *dentry,
1503                                   u32 av)
1504 {
1505         struct inode *inode = dentry->d_inode;
1506         struct common_audit_data ad;
1507
1508         COMMON_AUDIT_DATA_INIT(&ad, FS);
1509         ad.u.fs.path.mnt = mnt;
1510         ad.u.fs.path.dentry = dentry;
1511         return inode_has_perm(cred, inode, av, &ad, 0);
1512 }
1513
1514 /* Check whether a task can use an open file descriptor to
1515    access an inode in a given way.  Check access to the
1516    descriptor itself, and then use dentry_has_perm to
1517    check a particular permission to the file.
1518    Access to the descriptor is implicitly granted if it
1519    has the same SID as the process.  If av is zero, then
1520    access to the file is not checked, e.g. for cases
1521    where only the descriptor is affected like seek. */
1522 static int file_has_perm(const struct cred *cred,
1523                          struct file *file,
1524                          u32 av)
1525 {
1526         struct file_security_struct *fsec = file->f_security;
1527         struct inode *inode = file->f_path.dentry->d_inode;
1528         struct common_audit_data ad;
1529         u32 sid = cred_sid(cred);
1530         int rc;
1531
1532         COMMON_AUDIT_DATA_INIT(&ad, FS);
1533         ad.u.fs.path = file->f_path;
1534
1535         if (sid != fsec->sid) {
1536                 rc = avc_has_perm(sid, fsec->sid,
1537                                   SECCLASS_FD,
1538                                   FD__USE,
1539                                   &ad);
1540                 if (rc)
1541                         goto out;
1542         }
1543
1544         /* av is zero if only checking access to the descriptor. */
1545         rc = 0;
1546         if (av)
1547                 rc = inode_has_perm(cred, inode, av, &ad, 0);
1548
1549 out:
1550         return rc;
1551 }
1552
1553 /* Check whether a task can create a file. */
1554 static int may_create(struct inode *dir,
1555                       struct dentry *dentry,
1556                       u16 tclass)
1557 {
1558         const struct task_security_struct *tsec = current_security();
1559         struct inode_security_struct *dsec;
1560         struct superblock_security_struct *sbsec;
1561         u32 sid, newsid;
1562         struct common_audit_data ad;
1563         int rc;
1564
1565         dsec = dir->i_security;
1566         sbsec = dir->i_sb->s_security;
1567
1568         sid = tsec->sid;
1569         newsid = tsec->create_sid;
1570
1571         COMMON_AUDIT_DATA_INIT(&ad, FS);
1572         ad.u.fs.path.dentry = dentry;
1573
1574         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1575                           DIR__ADD_NAME | DIR__SEARCH,
1576                           &ad);
1577         if (rc)
1578                 return rc;
1579
1580         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1581                 rc = security_transition_sid(sid, dsec->sid, tclass, NULL, &newsid);
1582                 if (rc)
1583                         return rc;
1584         }
1585
1586         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1587         if (rc)
1588                 return rc;
1589
1590         return avc_has_perm(newsid, sbsec->sid,
1591                             SECCLASS_FILESYSTEM,
1592                             FILESYSTEM__ASSOCIATE, &ad);
1593 }
1594
1595 /* Check whether a task can create a key. */
1596 static int may_create_key(u32 ksid,
1597                           struct task_struct *ctx)
1598 {
1599         u32 sid = task_sid(ctx);
1600
1601         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1602 }
1603
1604 #define MAY_LINK        0
1605 #define MAY_UNLINK      1
1606 #define MAY_RMDIR       2
1607
1608 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1609 static int may_link(struct inode *dir,
1610                     struct dentry *dentry,
1611                     int kind)
1612
1613 {
1614         struct inode_security_struct *dsec, *isec;
1615         struct common_audit_data ad;
1616         u32 sid = current_sid();
1617         u32 av;
1618         int rc;
1619
1620         dsec = dir->i_security;
1621         isec = dentry->d_inode->i_security;
1622
1623         COMMON_AUDIT_DATA_INIT(&ad, FS);
1624         ad.u.fs.path.dentry = dentry;
1625
1626         av = DIR__SEARCH;
1627         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1628         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1629         if (rc)
1630                 return rc;
1631
1632         switch (kind) {
1633         case MAY_LINK:
1634                 av = FILE__LINK;
1635                 break;
1636         case MAY_UNLINK:
1637                 av = FILE__UNLINK;
1638                 break;
1639         case MAY_RMDIR:
1640                 av = DIR__RMDIR;
1641                 break;
1642         default:
1643                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1644                         __func__, kind);
1645                 return 0;
1646         }
1647
1648         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1649         return rc;
1650 }
1651
1652 static inline int may_rename(struct inode *old_dir,
1653                              struct dentry *old_dentry,
1654                              struct inode *new_dir,
1655                              struct dentry *new_dentry)
1656 {
1657         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1658         struct common_audit_data ad;
1659         u32 sid = current_sid();
1660         u32 av;
1661         int old_is_dir, new_is_dir;
1662         int rc;
1663
1664         old_dsec = old_dir->i_security;
1665         old_isec = old_dentry->d_inode->i_security;
1666         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1667         new_dsec = new_dir->i_security;
1668
1669         COMMON_AUDIT_DATA_INIT(&ad, FS);
1670
1671         ad.u.fs.path.dentry = old_dentry;
1672         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1673                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1674         if (rc)
1675                 return rc;
1676         rc = avc_has_perm(sid, old_isec->sid,
1677                           old_isec->sclass, FILE__RENAME, &ad);
1678         if (rc)
1679                 return rc;
1680         if (old_is_dir && new_dir != old_dir) {
1681                 rc = avc_has_perm(sid, old_isec->sid,
1682                                   old_isec->sclass, DIR__REPARENT, &ad);
1683                 if (rc)
1684                         return rc;
1685         }
1686
1687         ad.u.fs.path.dentry = new_dentry;
1688         av = DIR__ADD_NAME | DIR__SEARCH;
1689         if (new_dentry->d_inode)
1690                 av |= DIR__REMOVE_NAME;
1691         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1692         if (rc)
1693                 return rc;
1694         if (new_dentry->d_inode) {
1695                 new_isec = new_dentry->d_inode->i_security;
1696                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1697                 rc = avc_has_perm(sid, new_isec->sid,
1698                                   new_isec->sclass,
1699                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1700                 if (rc)
1701                         return rc;
1702         }
1703
1704         return 0;
1705 }
1706
1707 /* Check whether a task can perform a filesystem operation. */
1708 static int superblock_has_perm(const struct cred *cred,
1709                                struct super_block *sb,
1710                                u32 perms,
1711                                struct common_audit_data *ad)
1712 {
1713         struct superblock_security_struct *sbsec;
1714         u32 sid = cred_sid(cred);
1715
1716         sbsec = sb->s_security;
1717         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1718 }
1719
1720 /* Convert a Linux mode and permission mask to an access vector. */
1721 static inline u32 file_mask_to_av(int mode, int mask)
1722 {
1723         u32 av = 0;
1724
1725         if ((mode & S_IFMT) != S_IFDIR) {
1726                 if (mask & MAY_EXEC)
1727                         av |= FILE__EXECUTE;
1728                 if (mask & MAY_READ)
1729                         av |= FILE__READ;
1730
1731                 if (mask & MAY_APPEND)
1732                         av |= FILE__APPEND;
1733                 else if (mask & MAY_WRITE)
1734                         av |= FILE__WRITE;
1735
1736         } else {
1737                 if (mask & MAY_EXEC)
1738                         av |= DIR__SEARCH;
1739                 if (mask & MAY_WRITE)
1740                         av |= DIR__WRITE;
1741                 if (mask & MAY_READ)
1742                         av |= DIR__READ;
1743         }
1744
1745         return av;
1746 }
1747
1748 /* Convert a Linux file to an access vector. */
1749 static inline u32 file_to_av(struct file *file)
1750 {
1751         u32 av = 0;
1752
1753         if (file->f_mode & FMODE_READ)
1754                 av |= FILE__READ;
1755         if (file->f_mode & FMODE_WRITE) {
1756                 if (file->f_flags & O_APPEND)
1757                         av |= FILE__APPEND;
1758                 else
1759                         av |= FILE__WRITE;
1760         }
1761         if (!av) {
1762                 /*
1763                  * Special file opened with flags 3 for ioctl-only use.
1764                  */
1765                 av = FILE__IOCTL;
1766         }
1767
1768         return av;
1769 }
1770
1771 /*
1772  * Convert a file to an access vector and include the correct open
1773  * open permission.
1774  */
1775 static inline u32 open_file_to_av(struct file *file)
1776 {
1777         u32 av = file_to_av(file);
1778
1779         if (selinux_policycap_openperm)
1780                 av |= FILE__OPEN;
1781
1782         return av;
1783 }
1784
1785 /* Hook functions begin here. */
1786
1787 static int selinux_ptrace_access_check(struct task_struct *child,
1788                                      unsigned int mode)
1789 {
1790         int rc;
1791
1792         rc = cap_ptrace_access_check(child, mode);
1793         if (rc)
1794                 return rc;
1795
1796         if (mode == PTRACE_MODE_READ) {
1797                 u32 sid = current_sid();
1798                 u32 csid = task_sid(child);
1799                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1800         }
1801
1802         return current_has_perm(child, PROCESS__PTRACE);
1803 }
1804
1805 static int selinux_ptrace_traceme(struct task_struct *parent)
1806 {
1807         int rc;
1808
1809         rc = cap_ptrace_traceme(parent);
1810         if (rc)
1811                 return rc;
1812
1813         return task_has_perm(parent, current, PROCESS__PTRACE);
1814 }
1815
1816 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1817                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1818 {
1819         int error;
1820
1821         error = current_has_perm(target, PROCESS__GETCAP);
1822         if (error)
1823                 return error;
1824
1825         return cap_capget(target, effective, inheritable, permitted);
1826 }
1827
1828 static int selinux_capset(struct cred *new, const struct cred *old,
1829                           const kernel_cap_t *effective,
1830                           const kernel_cap_t *inheritable,
1831                           const kernel_cap_t *permitted)
1832 {
1833         int error;
1834
1835         error = cap_capset(new, old,
1836                                       effective, inheritable, permitted);
1837         if (error)
1838                 return error;
1839
1840         return cred_has_perm(old, new, PROCESS__SETCAP);
1841 }
1842
1843 /*
1844  * (This comment used to live with the selinux_task_setuid hook,
1845  * which was removed).
1846  *
1847  * Since setuid only affects the current process, and since the SELinux
1848  * controls are not based on the Linux identity attributes, SELinux does not
1849  * need to control this operation.  However, SELinux does control the use of
1850  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1851  */
1852
1853 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1854                            struct user_namespace *ns, int cap, int audit)
1855 {
1856         int rc;
1857
1858         rc = cap_capable(tsk, cred, ns, cap, audit);
1859         if (rc)
1860                 return rc;
1861
1862         return task_has_capability(tsk, cred, cap, audit);
1863 }
1864
1865 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1866 {
1867         const struct cred *cred = current_cred();
1868         int rc = 0;
1869
1870         if (!sb)
1871                 return 0;
1872
1873         switch (cmds) {
1874         case Q_SYNC:
1875         case Q_QUOTAON:
1876         case Q_QUOTAOFF:
1877         case Q_SETINFO:
1878         case Q_SETQUOTA:
1879                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1880                 break;
1881         case Q_GETFMT:
1882         case Q_GETINFO:
1883         case Q_GETQUOTA:
1884                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1885                 break;
1886         default:
1887                 rc = 0;  /* let the kernel handle invalid cmds */
1888                 break;
1889         }
1890         return rc;
1891 }
1892
1893 static int selinux_quota_on(struct dentry *dentry)
1894 {
1895         const struct cred *cred = current_cred();
1896
1897         return dentry_has_perm(cred, NULL, dentry, FILE__QUOTAON);
1898 }
1899
1900 static int selinux_syslog(int type)
1901 {
1902         int rc;
1903
1904         switch (type) {
1905         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
1906         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1907                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1908                 break;
1909         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1910         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
1911         /* Set level of messages printed to console */
1912         case SYSLOG_ACTION_CONSOLE_LEVEL:
1913                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1914                 break;
1915         case SYSLOG_ACTION_CLOSE:       /* Close log */
1916         case SYSLOG_ACTION_OPEN:        /* Open log */
1917         case SYSLOG_ACTION_READ:        /* Read from log */
1918         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
1919         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
1920         default:
1921                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1922                 break;
1923         }
1924         return rc;
1925 }
1926
1927 /*
1928  * Check that a process has enough memory to allocate a new virtual
1929  * mapping. 0 means there is enough memory for the allocation to
1930  * succeed and -ENOMEM implies there is not.
1931  *
1932  * Do not audit the selinux permission check, as this is applied to all
1933  * processes that allocate mappings.
1934  */
1935 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1936 {
1937         int rc, cap_sys_admin = 0;
1938
1939         rc = selinux_capable(current, current_cred(),
1940                              &init_user_ns, CAP_SYS_ADMIN,
1941                              SECURITY_CAP_NOAUDIT);
1942         if (rc == 0)
1943                 cap_sys_admin = 1;
1944
1945         return __vm_enough_memory(mm, pages, cap_sys_admin);
1946 }
1947
1948 /* binprm security operations */
1949
1950 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
1951 {
1952         const struct task_security_struct *old_tsec;
1953         struct task_security_struct *new_tsec;
1954         struct inode_security_struct *isec;
1955         struct common_audit_data ad;
1956         struct inode *inode = bprm->file->f_path.dentry->d_inode;
1957         int rc;
1958
1959         rc = cap_bprm_set_creds(bprm);
1960         if (rc)
1961                 return rc;
1962
1963         /* SELinux context only depends on initial program or script and not
1964          * the script interpreter */
1965         if (bprm->cred_prepared)
1966                 return 0;
1967
1968         old_tsec = current_security();
1969         new_tsec = bprm->cred->security;
1970         isec = inode->i_security;
1971
1972         /* Default to the current task SID. */
1973         new_tsec->sid = old_tsec->sid;
1974         new_tsec->osid = old_tsec->sid;
1975
1976         /* Reset fs, key, and sock SIDs on execve. */
1977         new_tsec->create_sid = 0;
1978         new_tsec->keycreate_sid = 0;
1979         new_tsec->sockcreate_sid = 0;
1980
1981         if (old_tsec->exec_sid) {
1982                 new_tsec->sid = old_tsec->exec_sid;
1983                 /* Reset exec SID on execve. */
1984                 new_tsec->exec_sid = 0;
1985         } else {
1986                 /* Check for a default transition on this program. */
1987                 rc = security_transition_sid(old_tsec->sid, isec->sid,
1988                                              SECCLASS_PROCESS, NULL,
1989                                              &new_tsec->sid);
1990                 if (rc)
1991                         return rc;
1992         }
1993
1994         COMMON_AUDIT_DATA_INIT(&ad, FS);
1995         ad.u.fs.path = bprm->file->f_path;
1996
1997         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
1998                 new_tsec->sid = old_tsec->sid;
1999
2000         if (new_tsec->sid == old_tsec->sid) {
2001                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2002                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2003                 if (rc)
2004                         return rc;
2005         } else {
2006                 /* Check permissions for the transition. */
2007                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2008                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2009                 if (rc)
2010                         return rc;
2011
2012                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2013                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2014                 if (rc)
2015                         return rc;
2016
2017                 /* Check for shared state */
2018                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2019                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2020                                           SECCLASS_PROCESS, PROCESS__SHARE,
2021                                           NULL);
2022                         if (rc)
2023                                 return -EPERM;
2024                 }
2025
2026                 /* Make sure that anyone attempting to ptrace over a task that
2027                  * changes its SID has the appropriate permit */
2028                 if (bprm->unsafe &
2029                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2030                         struct task_struct *tracer;
2031                         struct task_security_struct *sec;
2032                         u32 ptsid = 0;
2033
2034                         rcu_read_lock();
2035                         tracer = tracehook_tracer_task(current);
2036                         if (likely(tracer != NULL)) {
2037                                 sec = __task_cred(tracer)->security;
2038                                 ptsid = sec->sid;
2039                         }
2040                         rcu_read_unlock();
2041
2042                         if (ptsid != 0) {
2043                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2044                                                   SECCLASS_PROCESS,
2045                                                   PROCESS__PTRACE, NULL);
2046                                 if (rc)
2047                                         return -EPERM;
2048                         }
2049                 }
2050
2051                 /* Clear any possibly unsafe personality bits on exec: */
2052                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2053         }
2054
2055         return 0;
2056 }
2057
2058 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2059 {
2060         const struct task_security_struct *tsec = current_security();
2061         u32 sid, osid;
2062         int atsecure = 0;
2063
2064         sid = tsec->sid;
2065         osid = tsec->osid;
2066
2067         if (osid != sid) {
2068                 /* Enable secure mode for SIDs transitions unless
2069                    the noatsecure permission is granted between
2070                    the two SIDs, i.e. ahp returns 0. */
2071                 atsecure = avc_has_perm(osid, sid,
2072                                         SECCLASS_PROCESS,
2073                                         PROCESS__NOATSECURE, NULL);
2074         }
2075
2076         return (atsecure || cap_bprm_secureexec(bprm));
2077 }
2078
2079 extern struct vfsmount *selinuxfs_mount;
2080 extern struct dentry *selinux_null;
2081
2082 /* Derived from fs/exec.c:flush_old_files. */
2083 static inline void flush_unauthorized_files(const struct cred *cred,
2084                                             struct files_struct *files)
2085 {
2086         struct common_audit_data ad;
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                         struct inode *inode;
2099
2100                         /* Revalidate access to controlling tty.
2101                            Use inode_has_perm on the tty inode directly rather
2102                            than using file_has_perm, as this particular open
2103                            file may belong to another process and we are only
2104                            interested in the inode-based check here. */
2105                         file_priv = list_first_entry(&tty->tty_files,
2106                                                 struct tty_file_private, list);
2107                         file = file_priv->file;
2108                         inode = file->f_path.dentry->d_inode;
2109                         if (inode_has_perm(cred, inode,
2110                                            FILE__READ | FILE__WRITE, NULL, 0)) {
2111                                 drop_tty = 1;
2112                         }
2113                 }
2114                 spin_unlock(&tty_files_lock);
2115                 tty_kref_put(tty);
2116         }
2117         /* Reset controlling tty. */
2118         if (drop_tty)
2119                 no_tty();
2120
2121         /* Revalidate access to inherited open files. */
2122
2123         COMMON_AUDIT_DATA_INIT(&ad, FS);
2124
2125         spin_lock(&files->file_lock);
2126         for (;;) {
2127                 unsigned long set, i;
2128                 int fd;
2129
2130                 j++;
2131                 i = j * __NFDBITS;
2132                 fdt = files_fdtable(files);
2133                 if (i >= fdt->max_fds)
2134                         break;
2135                 set = fdt->open_fds->fds_bits[j];
2136                 if (!set)
2137                         continue;
2138                 spin_unlock(&files->file_lock);
2139                 for ( ; set ; i++, set >>= 1) {
2140                         if (set & 1) {
2141                                 file = fget(i);
2142                                 if (!file)
2143                                         continue;
2144                                 if (file_has_perm(cred,
2145                                                   file,
2146                                                   file_to_av(file))) {
2147                                         sys_close(i);
2148                                         fd = get_unused_fd();
2149                                         if (fd != i) {
2150                                                 if (fd >= 0)
2151                                                         put_unused_fd(fd);
2152                                                 fput(file);
2153                                                 continue;
2154                                         }
2155                                         if (devnull) {
2156                                                 get_file(devnull);
2157                                         } else {
2158                                                 devnull = dentry_open(
2159                                                         dget(selinux_null),
2160                                                         mntget(selinuxfs_mount),
2161                                                         O_RDWR, cred);
2162                                                 if (IS_ERR(devnull)) {
2163                                                         devnull = NULL;
2164                                                         put_unused_fd(fd);
2165                                                         fput(file);
2166                                                         continue;
2167                                                 }
2168                                         }
2169                                         fd_install(fd, devnull);
2170                                 }
2171                                 fput(file);
2172                         }
2173                 }
2174                 spin_lock(&files->file_lock);
2175
2176         }
2177         spin_unlock(&files->file_lock);
2178 }
2179
2180 /*
2181  * Prepare a process for imminent new credential changes due to exec
2182  */
2183 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2184 {
2185         struct task_security_struct *new_tsec;
2186         struct rlimit *rlim, *initrlim;
2187         int rc, i;
2188
2189         new_tsec = bprm->cred->security;
2190         if (new_tsec->sid == new_tsec->osid)
2191                 return;
2192
2193         /* Close files for which the new task SID is not authorized. */
2194         flush_unauthorized_files(bprm->cred, current->files);
2195
2196         /* Always clear parent death signal on SID transitions. */
2197         current->pdeath_signal = 0;
2198
2199         /* Check whether the new SID can inherit resource limits from the old
2200          * SID.  If not, reset all soft limits to the lower of the current
2201          * task's hard limit and the init task's soft limit.
2202          *
2203          * Note that the setting of hard limits (even to lower them) can be
2204          * controlled by the setrlimit check.  The inclusion of the init task's
2205          * soft limit into the computation is to avoid resetting soft limits
2206          * higher than the default soft limit for cases where the default is
2207          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2208          */
2209         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2210                           PROCESS__RLIMITINH, NULL);
2211         if (rc) {
2212                 /* protect against do_prlimit() */
2213                 task_lock(current);
2214                 for (i = 0; i < RLIM_NLIMITS; i++) {
2215                         rlim = current->signal->rlim + i;
2216                         initrlim = init_task.signal->rlim + i;
2217                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2218                 }
2219                 task_unlock(current);
2220                 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2221         }
2222 }
2223
2224 /*
2225  * Clean up the process immediately after the installation of new credentials
2226  * due to exec
2227  */
2228 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2229 {
2230         const struct task_security_struct *tsec = current_security();
2231         struct itimerval itimer;
2232         u32 osid, sid;
2233         int rc, i;
2234
2235         osid = tsec->osid;
2236         sid = tsec->sid;
2237
2238         if (sid == osid)
2239                 return;
2240
2241         /* Check whether the new SID can inherit signal state from the old SID.
2242          * If not, clear itimers to avoid subsequent signal generation and
2243          * flush and unblock signals.
2244          *
2245          * This must occur _after_ the task SID has been updated so that any
2246          * kill done after the flush will be checked against the new SID.
2247          */
2248         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2249         if (rc) {
2250                 memset(&itimer, 0, sizeof itimer);
2251                 for (i = 0; i < 3; i++)
2252                         do_setitimer(i, &itimer, NULL);
2253                 spin_lock_irq(&current->sighand->siglock);
2254                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2255                         __flush_signals(current);
2256                         flush_signal_handlers(current, 1);
2257                         sigemptyset(&current->blocked);
2258                 }
2259                 spin_unlock_irq(&current->sighand->siglock);
2260         }
2261
2262         /* Wake up the parent if it is waiting so that it can recheck
2263          * wait permission to the new task SID. */
2264         read_lock(&tasklist_lock);
2265         __wake_up_parent(current, current->real_parent);
2266         read_unlock(&tasklist_lock);
2267 }
2268
2269 /* superblock security operations */
2270
2271 static int selinux_sb_alloc_security(struct super_block *sb)
2272 {
2273         return superblock_alloc_security(sb);
2274 }
2275
2276 static void selinux_sb_free_security(struct super_block *sb)
2277 {
2278         superblock_free_security(sb);
2279 }
2280
2281 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2282 {
2283         if (plen > olen)
2284                 return 0;
2285
2286         return !memcmp(prefix, option, plen);
2287 }
2288
2289 static inline int selinux_option(char *option, int len)
2290 {
2291         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2292                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2293                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2294                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2295                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2296 }
2297
2298 static inline void take_option(char **to, char *from, int *first, int len)
2299 {
2300         if (!*first) {
2301                 **to = ',';
2302                 *to += 1;
2303         } else
2304                 *first = 0;
2305         memcpy(*to, from, len);
2306         *to += len;
2307 }
2308
2309 static inline void take_selinux_option(char **to, char *from, int *first,
2310                                        int len)
2311 {
2312         int current_size = 0;
2313
2314         if (!*first) {
2315                 **to = '|';
2316                 *to += 1;
2317         } else
2318                 *first = 0;
2319
2320         while (current_size < len) {
2321                 if (*from != '"') {
2322                         **to = *from;
2323                         *to += 1;
2324                 }
2325                 from += 1;
2326                 current_size += 1;
2327         }
2328 }
2329
2330 static int selinux_sb_copy_data(char *orig, char *copy)
2331 {
2332         int fnosec, fsec, rc = 0;
2333         char *in_save, *in_curr, *in_end;
2334         char *sec_curr, *nosec_save, *nosec;
2335         int open_quote = 0;
2336
2337         in_curr = orig;
2338         sec_curr = copy;
2339
2340         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2341         if (!nosec) {
2342                 rc = -ENOMEM;
2343                 goto out;
2344         }
2345
2346         nosec_save = nosec;
2347         fnosec = fsec = 1;
2348         in_save = in_end = orig;
2349
2350         do {
2351                 if (*in_end == '"')
2352                         open_quote = !open_quote;
2353                 if ((*in_end == ',' && open_quote == 0) ||
2354                                 *in_end == '\0') {
2355                         int len = in_end - in_curr;
2356
2357                         if (selinux_option(in_curr, len))
2358                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2359                         else
2360                                 take_option(&nosec, in_curr, &fnosec, len);
2361
2362                         in_curr = in_end + 1;
2363                 }
2364         } while (*in_end++);
2365
2366         strcpy(in_save, nosec_save);
2367         free_page((unsigned long)nosec_save);
2368 out:
2369         return rc;
2370 }
2371
2372 static int selinux_sb_remount(struct super_block *sb, void *data)
2373 {
2374         int rc, i, *flags;
2375         struct security_mnt_opts opts;
2376         char *secdata, **mount_options;
2377         struct superblock_security_struct *sbsec = sb->s_security;
2378
2379         if (!(sbsec->flags & SE_SBINITIALIZED))
2380                 return 0;
2381
2382         if (!data)
2383                 return 0;
2384
2385         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2386                 return 0;
2387
2388         security_init_mnt_opts(&opts);
2389         secdata = alloc_secdata();
2390         if (!secdata)
2391                 return -ENOMEM;
2392         rc = selinux_sb_copy_data(data, secdata);
2393         if (rc)
2394                 goto out_free_secdata;
2395
2396         rc = selinux_parse_opts_str(secdata, &opts);
2397         if (rc)
2398                 goto out_free_secdata;
2399
2400         mount_options = opts.mnt_opts;
2401         flags = opts.mnt_opts_flags;
2402
2403         for (i = 0; i < opts.num_mnt_opts; i++) {
2404                 u32 sid;
2405                 size_t len;
2406
2407                 if (flags[i] == SE_SBLABELSUPP)
2408                         continue;
2409                 len = strlen(mount_options[i]);
2410                 rc = security_context_to_sid(mount_options[i], len, &sid);
2411                 if (rc) {
2412                         printk(KERN_WARNING "SELinux: security_context_to_sid"
2413                                "(%s) failed for (dev %s, type %s) errno=%d\n",
2414                                mount_options[i], sb->s_id, sb->s_type->name, rc);
2415                         goto out_free_opts;
2416                 }
2417                 rc = -EINVAL;
2418                 switch (flags[i]) {
2419                 case FSCONTEXT_MNT:
2420                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2421                                 goto out_bad_option;
2422                         break;
2423                 case CONTEXT_MNT:
2424                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2425                                 goto out_bad_option;
2426                         break;
2427                 case ROOTCONTEXT_MNT: {
2428                         struct inode_security_struct *root_isec;
2429                         root_isec = sb->s_root->d_inode->i_security;
2430
2431                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2432                                 goto out_bad_option;
2433                         break;
2434                 }
2435                 case DEFCONTEXT_MNT:
2436                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2437                                 goto out_bad_option;
2438                         break;
2439                 default:
2440                         goto out_free_opts;
2441                 }
2442         }
2443
2444         rc = 0;
2445 out_free_opts:
2446         security_free_mnt_opts(&opts);
2447 out_free_secdata:
2448         free_secdata(secdata);
2449         return rc;
2450 out_bad_option:
2451         printk(KERN_WARNING "SELinux: unable to change security options "
2452                "during remount (dev %s, type=%s)\n", sb->s_id,
2453                sb->s_type->name);
2454         goto out_free_opts;
2455 }
2456
2457 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2458 {
2459         const struct cred *cred = current_cred();
2460         struct common_audit_data ad;
2461         int rc;
2462
2463         rc = superblock_doinit(sb, data);
2464         if (rc)
2465                 return rc;
2466
2467         /* Allow all mounts performed by the kernel */
2468         if (flags & MS_KERNMOUNT)
2469                 return 0;
2470
2471         COMMON_AUDIT_DATA_INIT(&ad, FS);
2472         ad.u.fs.path.dentry = sb->s_root;
2473         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2474 }
2475
2476 static int selinux_sb_statfs(struct dentry *dentry)
2477 {
2478         const struct cred *cred = current_cred();
2479         struct common_audit_data ad;
2480
2481         COMMON_AUDIT_DATA_INIT(&ad, FS);
2482         ad.u.fs.path.dentry = dentry->d_sb->s_root;
2483         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2484 }
2485
2486 static int selinux_mount(char *dev_name,
2487                          struct path *path,
2488                          char *type,
2489                          unsigned long flags,
2490                          void *data)
2491 {
2492         const struct cred *cred = current_cred();
2493
2494         if (flags & MS_REMOUNT)
2495                 return superblock_has_perm(cred, path->mnt->mnt_sb,
2496                                            FILESYSTEM__REMOUNT, NULL);
2497         else
2498                 return dentry_has_perm(cred, path->mnt, path->dentry,
2499                                        FILE__MOUNTON);
2500 }
2501
2502 static int selinux_umount(struct vfsmount *mnt, int flags)
2503 {
2504         const struct cred *cred = current_cred();
2505
2506         return superblock_has_perm(cred, mnt->mnt_sb,
2507                                    FILESYSTEM__UNMOUNT, NULL);
2508 }
2509
2510 /* inode security operations */
2511
2512 static int selinux_inode_alloc_security(struct inode *inode)
2513 {
2514         return inode_alloc_security(inode);
2515 }
2516
2517 static void selinux_inode_free_security(struct inode *inode)
2518 {
2519         inode_free_security(inode);
2520 }
2521
2522 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2523                                        const struct qstr *qstr, char **name,
2524                                        void **value, size_t *len)
2525 {
2526         const struct task_security_struct *tsec = current_security();
2527         struct inode_security_struct *dsec;
2528         struct superblock_security_struct *sbsec;
2529         u32 sid, newsid, clen;
2530         int rc;
2531         char *namep = NULL, *context;
2532
2533         dsec = dir->i_security;
2534         sbsec = dir->i_sb->s_security;
2535
2536         sid = tsec->sid;
2537         newsid = tsec->create_sid;
2538
2539         if ((sbsec->flags & SE_SBINITIALIZED) &&
2540             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2541                 newsid = sbsec->mntpoint_sid;
2542         else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2543                 rc = security_transition_sid(sid, dsec->sid,
2544                                              inode_mode_to_security_class(inode->i_mode),
2545                                              qstr, &newsid);
2546                 if (rc) {
2547                         printk(KERN_WARNING "%s:  "
2548                                "security_transition_sid failed, rc=%d (dev=%s "
2549                                "ino=%ld)\n",
2550                                __func__,
2551                                -rc, inode->i_sb->s_id, inode->i_ino);
2552                         return rc;
2553                 }
2554         }
2555
2556         /* Possibly defer initialization to selinux_complete_init. */
2557         if (sbsec->flags & SE_SBINITIALIZED) {
2558                 struct inode_security_struct *isec = inode->i_security;
2559                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2560                 isec->sid = newsid;
2561                 isec->initialized = 1;
2562         }
2563
2564         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2565                 return -EOPNOTSUPP;
2566
2567         if (name) {
2568                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2569                 if (!namep)
2570                         return -ENOMEM;
2571                 *name = namep;
2572         }
2573
2574         if (value && len) {
2575                 rc = security_sid_to_context_force(newsid, &context, &clen);
2576                 if (rc) {
2577                         kfree(namep);
2578                         return rc;
2579                 }
2580                 *value = context;
2581                 *len = clen;
2582         }
2583
2584         return 0;
2585 }
2586
2587 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2588 {
2589         return may_create(dir, dentry, SECCLASS_FILE);
2590 }
2591
2592 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2593 {
2594         return may_link(dir, old_dentry, MAY_LINK);
2595 }
2596
2597 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2598 {
2599         return may_link(dir, dentry, MAY_UNLINK);
2600 }
2601
2602 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2603 {
2604         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2605 }
2606
2607 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2608 {
2609         return may_create(dir, dentry, SECCLASS_DIR);
2610 }
2611
2612 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2613 {
2614         return may_link(dir, dentry, MAY_RMDIR);
2615 }
2616
2617 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2618 {
2619         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2620 }
2621
2622 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2623                                 struct inode *new_inode, struct dentry *new_dentry)
2624 {
2625         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2626 }
2627
2628 static int selinux_inode_readlink(struct dentry *dentry)
2629 {
2630         const struct cred *cred = current_cred();
2631
2632         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2633 }
2634
2635 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2636 {
2637         const struct cred *cred = current_cred();
2638
2639         return dentry_has_perm(cred, NULL, dentry, FILE__READ);
2640 }
2641
2642 static int selinux_inode_permission(struct inode *inode, int mask, unsigned flags)
2643 {
2644         const struct cred *cred = current_cred();
2645         struct common_audit_data ad;
2646         u32 perms;
2647         bool from_access;
2648
2649         from_access = mask & MAY_ACCESS;
2650         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2651
2652         /* No permission to check.  Existence test. */
2653         if (!mask)
2654                 return 0;
2655
2656         COMMON_AUDIT_DATA_INIT(&ad, FS);
2657         ad.u.fs.inode = inode;
2658
2659         if (from_access)
2660                 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2661
2662         perms = file_mask_to_av(inode->i_mode, mask);
2663
2664         return inode_has_perm(cred, inode, perms, &ad, flags);
2665 }
2666
2667 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2668 {
2669         const struct cred *cred = current_cred();
2670         unsigned int ia_valid = iattr->ia_valid;
2671
2672         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2673         if (ia_valid & ATTR_FORCE) {
2674                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2675                               ATTR_FORCE);
2676                 if (!ia_valid)
2677                         return 0;
2678         }
2679
2680         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2681                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2682                 return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2683
2684         return dentry_has_perm(cred, NULL, dentry, FILE__WRITE);
2685 }
2686
2687 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2688 {
2689         const struct cred *cred = current_cred();
2690
2691         return dentry_has_perm(cred, mnt, dentry, FILE__GETATTR);
2692 }
2693
2694 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2695 {
2696         const struct cred *cred = current_cred();
2697
2698         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2699                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2700                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2701                         if (!capable(CAP_SETFCAP))
2702                                 return -EPERM;
2703                 } else if (!capable(CAP_SYS_ADMIN)) {
2704                         /* A different attribute in the security namespace.
2705                            Restrict to administrator. */
2706                         return -EPERM;
2707                 }
2708         }
2709
2710         /* Not an attribute we recognize, so just check the
2711            ordinary setattr permission. */
2712         return dentry_has_perm(cred, NULL, dentry, FILE__SETATTR);
2713 }
2714
2715 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2716                                   const void *value, size_t size, int flags)
2717 {
2718         struct inode *inode = dentry->d_inode;
2719         struct inode_security_struct *isec = inode->i_security;
2720         struct superblock_security_struct *sbsec;
2721         struct common_audit_data ad;
2722         u32 newsid, sid = current_sid();
2723         int rc = 0;
2724
2725         if (strcmp(name, XATTR_NAME_SELINUX))
2726                 return selinux_inode_setotherxattr(dentry, name);
2727
2728         sbsec = inode->i_sb->s_security;
2729         if (!(sbsec->flags & SE_SBLABELSUPP))
2730                 return -EOPNOTSUPP;
2731
2732         if (!inode_owner_or_capable(inode))
2733                 return -EPERM;
2734
2735         COMMON_AUDIT_DATA_INIT(&ad, FS);
2736         ad.u.fs.path.dentry = dentry;
2737
2738         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2739                           FILE__RELABELFROM, &ad);
2740         if (rc)
2741                 return rc;
2742
2743         rc = security_context_to_sid(value, size, &newsid);
2744         if (rc == -EINVAL) {
2745                 if (!capable(CAP_MAC_ADMIN))
2746                         return rc;
2747                 rc = security_context_to_sid_force(value, size, &newsid);
2748         }
2749         if (rc)
2750                 return rc;
2751
2752         rc = avc_has_perm(sid, newsid, isec->sclass,
2753                           FILE__RELABELTO, &ad);
2754         if (rc)
2755                 return rc;
2756
2757         rc = security_validate_transition(isec->sid, newsid, sid,
2758                                           isec->sclass);
2759         if (rc)
2760                 return rc;
2761
2762         return avc_has_perm(newsid,
2763                             sbsec->sid,
2764                             SECCLASS_FILESYSTEM,
2765                             FILESYSTEM__ASSOCIATE,
2766                             &ad);
2767 }
2768
2769 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2770                                         const void *value, size_t size,
2771                                         int flags)
2772 {
2773         struct inode *inode = dentry->d_inode;
2774         struct inode_security_struct *isec = inode->i_security;
2775         u32 newsid;
2776         int rc;
2777
2778         if (strcmp(name, XATTR_NAME_SELINUX)) {
2779                 /* Not an attribute we recognize, so nothing to do. */
2780                 return;
2781         }
2782
2783         rc = security_context_to_sid_force(value, size, &newsid);
2784         if (rc) {
2785                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2786                        "for (%s, %lu), rc=%d\n",
2787                        inode->i_sb->s_id, inode->i_ino, -rc);
2788                 return;
2789         }
2790
2791         isec->sid = newsid;
2792         return;
2793 }
2794
2795 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2796 {
2797         const struct cred *cred = current_cred();
2798
2799         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2800 }
2801
2802 static int selinux_inode_listxattr(struct dentry *dentry)
2803 {
2804         const struct cred *cred = current_cred();
2805
2806         return dentry_has_perm(cred, NULL, dentry, FILE__GETATTR);
2807 }
2808
2809 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2810 {
2811         if (strcmp(name, XATTR_NAME_SELINUX))
2812                 return selinux_inode_setotherxattr(dentry, name);
2813
2814         /* No one is allowed to remove a SELinux security label.
2815            You can change the label, but all data must be labeled. */
2816         return -EACCES;
2817 }
2818
2819 /*
2820  * Copy the inode security context value to the user.
2821  *
2822  * Permission check is handled by selinux_inode_getxattr hook.
2823  */
2824 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2825 {
2826         u32 size;
2827         int error;
2828         char *context = NULL;
2829         struct inode_security_struct *isec = inode->i_security;
2830
2831         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2832                 return -EOPNOTSUPP;
2833
2834         /*
2835          * If the caller has CAP_MAC_ADMIN, then get the raw context
2836          * value even if it is not defined by current policy; otherwise,
2837          * use the in-core value under current policy.
2838          * Use the non-auditing forms of the permission checks since
2839          * getxattr may be called by unprivileged processes commonly
2840          * and lack of permission just means that we fall back to the
2841          * in-core context value, not a denial.
2842          */
2843         error = selinux_capable(current, current_cred(),
2844                                 &init_user_ns, CAP_MAC_ADMIN,
2845                                 SECURITY_CAP_NOAUDIT);
2846         if (!error)
2847                 error = security_sid_to_context_force(isec->sid, &context,
2848                                                       &size);
2849         else
2850                 error = security_sid_to_context(isec->sid, &context, &size);
2851         if (error)
2852                 return error;
2853         error = size;
2854         if (alloc) {
2855                 *buffer = context;
2856                 goto out_nofree;
2857         }
2858         kfree(context);
2859 out_nofree:
2860         return error;
2861 }
2862
2863 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2864                                      const void *value, size_t size, int flags)
2865 {
2866         struct inode_security_struct *isec = inode->i_security;
2867         u32 newsid;
2868         int rc;
2869
2870         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2871                 return -EOPNOTSUPP;
2872
2873         if (!value || !size)
2874                 return -EACCES;
2875
2876         rc = security_context_to_sid((void *)value, size, &newsid);
2877         if (rc)
2878                 return rc;
2879
2880         isec->sid = newsid;
2881         isec->initialized = 1;
2882         return 0;
2883 }
2884
2885 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2886 {
2887         const int len = sizeof(XATTR_NAME_SELINUX);
2888         if (buffer && len <= buffer_size)
2889                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2890         return len;
2891 }
2892
2893 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2894 {
2895         struct inode_security_struct *isec = inode->i_security;
2896         *secid = isec->sid;
2897 }
2898
2899 /* file security operations */
2900
2901 static int selinux_revalidate_file_permission(struct file *file, int mask)
2902 {
2903         const struct cred *cred = current_cred();
2904         struct inode *inode = file->f_path.dentry->d_inode;
2905
2906         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2907         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2908                 mask |= MAY_APPEND;
2909
2910         return file_has_perm(cred, file,
2911                              file_mask_to_av(inode->i_mode, mask));
2912 }
2913
2914 static int selinux_file_permission(struct file *file, int mask)
2915 {
2916         struct inode *inode = file->f_path.dentry->d_inode;
2917         struct file_security_struct *fsec = file->f_security;
2918         struct inode_security_struct *isec = inode->i_security;
2919         u32 sid = current_sid();
2920
2921         if (!mask)
2922                 /* No permission to check.  Existence test. */
2923                 return 0;
2924
2925         if (sid == fsec->sid && fsec->isid == isec->sid &&
2926             fsec->pseqno == avc_policy_seqno())
2927                 /* No change since dentry_open check. */
2928                 return 0;
2929
2930         return selinux_revalidate_file_permission(file, mask);
2931 }
2932
2933 static int selinux_file_alloc_security(struct file *file)
2934 {
2935         return file_alloc_security(file);
2936 }
2937
2938 static void selinux_file_free_security(struct file *file)
2939 {
2940         file_free_security(file);
2941 }
2942
2943 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2944                               unsigned long arg)
2945 {
2946         const struct cred *cred = current_cred();
2947         int error = 0;
2948
2949         switch (cmd) {
2950         case FIONREAD:
2951         /* fall through */
2952         case FIBMAP:
2953         /* fall through */
2954         case FIGETBSZ:
2955         /* fall through */
2956         case EXT2_IOC_GETFLAGS:
2957         /* fall through */
2958         case EXT2_IOC_GETVERSION:
2959                 error = file_has_perm(cred, file, FILE__GETATTR);
2960                 break;
2961
2962         case EXT2_IOC_SETFLAGS:
2963         /* fall through */
2964         case EXT2_IOC_SETVERSION:
2965                 error = file_has_perm(cred, file, FILE__SETATTR);
2966                 break;
2967
2968         /* sys_ioctl() checks */
2969         case FIONBIO:
2970         /* fall through */
2971         case FIOASYNC:
2972                 error = file_has_perm(cred, file, 0);
2973                 break;
2974
2975         case KDSKBENT:
2976         case KDSKBSENT:
2977                 error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG,
2978                                         SECURITY_CAP_AUDIT);
2979                 break;
2980
2981         /* default case assumes that the command will go
2982          * to the file's ioctl() function.
2983          */
2984         default:
2985                 error = file_has_perm(cred, file, FILE__IOCTL);
2986         }
2987         return error;
2988 }
2989
2990 static int default_noexec;
2991
2992 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
2993 {
2994         const struct cred *cred = current_cred();
2995         int rc = 0;
2996
2997         if (default_noexec &&
2998             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
2999                 /*
3000                  * We are making executable an anonymous mapping or a
3001                  * private file mapping that will also be writable.
3002                  * This has an additional check.
3003                  */
3004                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3005                 if (rc)
3006                         goto error;
3007         }
3008
3009         if (file) {
3010                 /* read access is always possible with a mapping */
3011                 u32 av = FILE__READ;
3012
3013                 /* write access only matters if the mapping is shared */
3014                 if (shared && (prot & PROT_WRITE))
3015                         av |= FILE__WRITE;
3016
3017                 if (prot & PROT_EXEC)
3018                         av |= FILE__EXECUTE;
3019
3020                 return file_has_perm(cred, file, av);
3021         }
3022
3023 error:
3024         return rc;
3025 }
3026
3027 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3028                              unsigned long prot, unsigned long flags,
3029                              unsigned long addr, unsigned long addr_only)
3030 {
3031         int rc = 0;
3032         u32 sid = current_sid();
3033
3034         /*
3035          * notice that we are intentionally putting the SELinux check before
3036          * the secondary cap_file_mmap check.  This is such a likely attempt
3037          * at bad behaviour/exploit that we always want to get the AVC, even
3038          * if DAC would have also denied the operation.
3039          */
3040         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3041                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3042                                   MEMPROTECT__MMAP_ZERO, NULL);
3043                 if (rc)
3044                         return rc;
3045         }
3046
3047         /* do DAC check on address space usage */
3048         rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3049         if (rc || addr_only)
3050                 return rc;
3051
3052         if (selinux_checkreqprot)
3053                 prot = reqprot;
3054
3055         return file_map_prot_check(file, prot,
3056                                    (flags & MAP_TYPE) == MAP_SHARED);
3057 }
3058
3059 static int selinux_file_mprotect(struct vm_area_struct *vma,
3060                                  unsigned long reqprot,
3061                                  unsigned long prot)
3062 {
3063         const struct cred *cred = current_cred();
3064
3065         if (selinux_checkreqprot)
3066                 prot = reqprot;
3067
3068         if (default_noexec &&
3069             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3070                 int rc = 0;
3071                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3072                     vma->vm_end <= vma->vm_mm->brk) {
3073                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3074                 } else if (!vma->vm_file &&
3075                            vma->vm_start <= vma->vm_mm->start_stack &&
3076                            vma->vm_end >= vma->vm_mm->start_stack) {
3077                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3078                 } else if (vma->vm_file && vma->anon_vma) {
3079                         /*
3080                          * We are making executable a file mapping that has
3081                          * had some COW done. Since pages might have been
3082                          * written, check ability to execute the possibly
3083                          * modified content.  This typically should only
3084                          * occur for text relocations.
3085                          */
3086                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3087                 }
3088                 if (rc)
3089                         return rc;
3090         }
3091
3092         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3093 }
3094
3095 static int selinux_file_lock(struct file *file, unsigned int cmd)
3096 {
3097         const struct cred *cred = current_cred();
3098
3099         return file_has_perm(cred, file, FILE__LOCK);
3100 }
3101
3102 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3103                               unsigned long arg)
3104 {
3105         const struct cred *cred = current_cred();
3106         int err = 0;
3107
3108         switch (cmd) {
3109         case F_SETFL:
3110                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3111                         err = -EINVAL;
3112                         break;
3113                 }
3114
3115                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3116                         err = file_has_perm(cred, file, FILE__WRITE);
3117                         break;
3118                 }
3119                 /* fall through */
3120         case F_SETOWN:
3121         case F_SETSIG:
3122         case F_GETFL:
3123         case F_GETOWN:
3124         case F_GETSIG:
3125                 /* Just check FD__USE permission */
3126                 err = file_has_perm(cred, file, 0);
3127                 break;
3128         case F_GETLK:
3129         case F_SETLK:
3130         case F_SETLKW:
3131 #if BITS_PER_LONG == 32
3132         case F_GETLK64:
3133         case F_SETLK64:
3134         case F_SETLKW64:
3135 #endif
3136                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3137                         err = -EINVAL;
3138                         break;
3139                 }
3140                 err = file_has_perm(cred, file, FILE__LOCK);
3141                 break;
3142         }
3143
3144         return err;
3145 }
3146
3147 static int selinux_file_set_fowner(struct file *file)
3148 {
3149         struct file_security_struct *fsec;
3150
3151         fsec = file->f_security;
3152         fsec->fown_sid = current_sid();
3153
3154         return 0;
3155 }
3156
3157 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3158                                        struct fown_struct *fown, int signum)
3159 {
3160         struct file *file;
3161         u32 sid = task_sid(tsk);
3162         u32 perm;
3163         struct file_security_struct *fsec;
3164
3165         /* struct fown_struct is never outside the context of a struct file */
3166         file = container_of(fown, struct file, f_owner);
3167
3168         fsec = file->f_security;
3169
3170         if (!signum)
3171                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3172         else
3173                 perm = signal_to_av(signum);
3174
3175         return avc_has_perm(fsec->fown_sid, sid,
3176                             SECCLASS_PROCESS, perm, NULL);
3177 }
3178
3179 static int selinux_file_receive(struct file *file)
3180 {
3181         const struct cred *cred = current_cred();
3182
3183         return file_has_perm(cred, file, file_to_av(file));
3184 }
3185
3186 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3187 {
3188         struct file_security_struct *fsec;
3189         struct inode *inode;
3190         struct inode_security_struct *isec;
3191
3192         inode = file->f_path.dentry->d_inode;
3193         fsec = file->f_security;
3194         isec = inode->i_security;
3195         /*
3196          * Save inode label and policy sequence number
3197          * at open-time so that selinux_file_permission
3198          * can determine whether revalidation is necessary.
3199          * Task label is already saved in the file security
3200          * struct as its SID.
3201          */
3202         fsec->isid = isec->sid;
3203         fsec->pseqno = avc_policy_seqno();
3204         /*
3205          * Since the inode label or policy seqno may have changed
3206          * between the selinux_inode_permission check and the saving
3207          * of state above, recheck that access is still permitted.
3208          * Otherwise, access might never be revalidated against the
3209          * new inode label or new policy.
3210          * This check is not redundant - do not remove.
3211          */
3212         return inode_has_perm(cred, inode, open_file_to_av(file), NULL, 0);
3213 }
3214
3215 /* task security operations */
3216
3217 static int selinux_task_create(unsigned long clone_flags)
3218 {
3219         return current_has_perm(current, PROCESS__FORK);
3220 }
3221
3222 /*
3223  * allocate the SELinux part of blank credentials
3224  */
3225 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3226 {
3227         struct task_security_struct *tsec;
3228
3229         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3230         if (!tsec)
3231                 return -ENOMEM;
3232
3233         cred->security = tsec;
3234         return 0;
3235 }
3236
3237 /*
3238  * detach and free the LSM part of a set of credentials
3239  */
3240 static void selinux_cred_free(struct cred *cred)
3241 {
3242         struct task_security_struct *tsec = cred->security;
3243
3244         /*
3245          * cred->security == NULL if security_cred_alloc_blank() or
3246          * security_prepare_creds() returned an error.
3247          */
3248         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3249         cred->security = (void *) 0x7UL;
3250         kfree(tsec);
3251 }
3252
3253 /*
3254  * prepare a new set of credentials for modification
3255  */
3256 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3257                                 gfp_t gfp)
3258 {
3259         const struct task_security_struct *old_tsec;
3260         struct task_security_struct *tsec;
3261
3262         old_tsec = old->security;
3263
3264         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3265         if (!tsec)
3266                 return -ENOMEM;
3267
3268         new->security = tsec;
3269         return 0;
3270 }
3271
3272 /*
3273  * transfer the SELinux data to a blank set of creds
3274  */
3275 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3276 {
3277         const struct task_security_struct *old_tsec = old->security;
3278         struct task_security_struct *tsec = new->security;
3279
3280         *tsec = *old_tsec;
3281 }
3282
3283 /*
3284  * set the security data for a kernel service
3285  * - all the creation contexts are set to unlabelled
3286  */
3287 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3288 {
3289         struct task_security_struct *tsec = new->security;
3290         u32 sid = current_sid();
3291         int ret;
3292
3293         ret = avc_has_perm(sid, secid,
3294                            SECCLASS_KERNEL_SERVICE,
3295                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3296                            NULL);
3297         if (ret == 0) {
3298                 tsec->sid = secid;
3299                 tsec->create_sid = 0;
3300                 tsec->keycreate_sid = 0;
3301                 tsec->sockcreate_sid = 0;
3302         }
3303         return ret;
3304 }
3305
3306 /*
3307  * set the file creation context in a security record to the same as the
3308  * objective context of the specified inode
3309  */
3310 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3311 {
3312         struct inode_security_struct *isec = inode->i_security;
3313         struct task_security_struct *tsec = new->security;
3314         u32 sid = current_sid();
3315         int ret;
3316
3317         ret = avc_has_perm(sid, isec->sid,
3318                            SECCLASS_KERNEL_SERVICE,
3319                            KERNEL_SERVICE__CREATE_FILES_AS,
3320                            NULL);
3321
3322         if (ret == 0)
3323                 tsec->create_sid = isec->sid;
3324         return ret;
3325 }
3326
3327 static int selinux_kernel_module_request(char *kmod_name)
3328 {
3329         u32 sid;
3330         struct common_audit_data ad;
3331
3332         sid = task_sid(current);
3333
3334         COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3335         ad.u.kmod_name = kmod_name;
3336
3337         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3338                             SYSTEM__MODULE_REQUEST, &ad);
3339 }
3340
3341 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3342 {
3343         return current_has_perm(p, PROCESS__SETPGID);
3344 }
3345
3346 static int selinux_task_getpgid(struct task_struct *p)
3347 {
3348         return current_has_perm(p, PROCESS__GETPGID);
3349 }
3350
3351 static int selinux_task_getsid(struct task_struct *p)
3352 {
3353         return current_has_perm(p, PROCESS__GETSESSION);
3354 }
3355
3356 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3357 {
3358         *secid = task_sid(p);
3359 }
3360
3361 static int selinux_task_setnice(struct task_struct *p, int nice)
3362 {
3363         int rc;
3364
3365         rc = cap_task_setnice(p, nice);
3366         if (rc)
3367                 return rc;
3368
3369         return current_has_perm(p, PROCESS__SETSCHED);
3370 }
3371
3372 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3373 {
3374         int rc;
3375
3376         rc = cap_task_setioprio(p, ioprio);
3377         if (rc)
3378                 return rc;
3379
3380         return current_has_perm(p, PROCESS__SETSCHED);
3381 }
3382
3383 static int selinux_task_getioprio(struct task_struct *p)
3384 {
3385         return current_has_perm(p, PROCESS__GETSCHED);
3386 }
3387
3388 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3389                 struct rlimit *new_rlim)
3390 {
3391         struct rlimit *old_rlim = p->signal->rlim + resource;
3392
3393         /* Control the ability to change the hard limit (whether
3394            lowering or raising it), so that the hard limit can
3395            later be used as a safe reset point for the soft limit
3396            upon context transitions.  See selinux_bprm_committing_creds. */
3397         if (old_rlim->rlim_max != new_rlim->rlim_max)
3398                 return current_has_perm(p, PROCESS__SETRLIMIT);
3399
3400         return 0;
3401 }
3402
3403 static int selinux_task_setscheduler(struct task_struct *p)
3404 {
3405         int rc;
3406
3407         rc = cap_task_setscheduler(p);
3408         if (rc)
3409                 return rc;
3410
3411         return current_has_perm(p, PROCESS__SETSCHED);
3412 }
3413
3414 static int selinux_task_getscheduler(struct task_struct *p)
3415 {
3416         return current_has_perm(p, PROCESS__GETSCHED);
3417 }
3418
3419 static int selinux_task_movememory(struct task_struct *p)
3420 {
3421         return current_has_perm(p, PROCESS__SETSCHED);
3422 }
3423
3424 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3425                                 int sig, u32 secid)
3426 {
3427         u32 perm;
3428         int rc;
3429
3430         if (!sig)
3431                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3432         else
3433                 perm = signal_to_av(sig);
3434         if (secid)
3435                 rc = avc_has_perm(secid, task_sid(p),
3436                                   SECCLASS_PROCESS, perm, NULL);
3437         else
3438                 rc = current_has_perm(p, perm);
3439         return rc;
3440 }
3441
3442 static int selinux_task_wait(struct task_struct *p)
3443 {
3444         return task_has_perm(p, current, PROCESS__SIGCHLD);
3445 }
3446
3447 static void selinux_task_to_inode(struct task_struct *p,
3448                                   struct inode *inode)
3449 {
3450         struct inode_security_struct *isec = inode->i_security;
3451         u32 sid = task_sid(p);
3452
3453         isec->sid = sid;
3454         isec->initialized = 1;
3455 }
3456
3457 /* Returns error only if unable to parse addresses */
3458 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3459                         struct common_audit_data *ad, u8 *proto)
3460 {
3461         int offset, ihlen, ret = -EINVAL;
3462         struct iphdr _iph, *ih;
3463
3464         offset = skb_network_offset(skb);
3465         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3466         if (ih == NULL)
3467                 goto out;
3468
3469         ihlen = ih->ihl * 4;
3470         if (ihlen < sizeof(_iph))
3471                 goto out;
3472
3473         ad->u.net.v4info.saddr = ih->saddr;
3474         ad->u.net.v4info.daddr = ih->daddr;
3475         ret = 0;
3476
3477         if (proto)
3478                 *proto = ih->protocol;
3479
3480         switch (ih->protocol) {
3481         case IPPROTO_TCP: {
3482                 struct tcphdr _tcph, *th;
3483
3484                 if (ntohs(ih->frag_off) & IP_OFFSET)
3485                         break;
3486
3487                 offset += ihlen;
3488                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3489                 if (th == NULL)
3490                         break;
3491
3492                 ad->u.net.sport = th->source;
3493                 ad->u.net.dport = th->dest;
3494                 break;
3495         }
3496
3497         case IPPROTO_UDP: {
3498                 struct udphdr _udph, *uh;
3499
3500                 if (ntohs(ih->frag_off) & IP_OFFSET)
3501                         break;
3502
3503                 offset += ihlen;
3504                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3505                 if (uh == NULL)
3506                         break;
3507
3508                 ad->u.net.sport = uh->source;
3509                 ad->u.net.dport = uh->dest;
3510                 break;
3511         }
3512
3513         case IPPROTO_DCCP: {
3514                 struct dccp_hdr _dccph, *dh;
3515
3516                 if (ntohs(ih->frag_off) & IP_OFFSET)
3517                         break;
3518
3519                 offset += ihlen;
3520                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3521                 if (dh == NULL)
3522                         break;
3523
3524                 ad->u.net.sport = dh->dccph_sport;
3525                 ad->u.net.dport = dh->dccph_dport;
3526                 break;
3527         }
3528
3529         default:
3530                 break;
3531         }
3532 out:
3533         return ret;
3534 }
3535
3536 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3537
3538 /* Returns error only if unable to parse addresses */
3539 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3540                         struct common_audit_data *ad, u8 *proto)
3541 {
3542         u8 nexthdr;
3543         int ret = -EINVAL, offset;
3544         struct ipv6hdr _ipv6h, *ip6;
3545
3546         offset = skb_network_offset(skb);
3547         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3548         if (ip6 == NULL)
3549                 goto out;
3550
3551         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3552         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3553         ret = 0;
3554
3555         nexthdr = ip6->nexthdr;
3556         offset += sizeof(_ipv6h);
3557         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3558         if (offset < 0)
3559                 goto out;
3560
3561         if (proto)
3562                 *proto = nexthdr;
3563
3564         switch (nexthdr) {
3565         case IPPROTO_TCP: {
3566                 struct tcphdr _tcph, *th;
3567
3568                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3569                 if (th == NULL)
3570                         break;
3571
3572                 ad->u.net.sport = th->source;
3573                 ad->u.net.dport = th->dest;
3574                 break;
3575         }
3576
3577         case IPPROTO_UDP: {
3578                 struct udphdr _udph, *uh;
3579
3580                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3581                 if (uh == NULL)
3582                         break;
3583
3584                 ad->u.net.sport = uh->source;
3585                 ad->u.net.dport = uh->dest;
3586                 break;
3587         }
3588
3589         case IPPROTO_DCCP: {
3590                 struct dccp_hdr _dccph, *dh;
3591
3592                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3593                 if (dh == NULL)
3594                         break;
3595
3596                 ad->u.net.sport = dh->dccph_sport;
3597                 ad->u.net.dport = dh->dccph_dport;
3598                 break;
3599         }
3600
3601         /* includes fragments */
3602         default:
3603                 break;
3604         }
3605 out:
3606         return ret;
3607 }
3608
3609 #endif /* IPV6 */
3610
3611 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3612                              char **_addrp, int src, u8 *proto)
3613 {
3614         char *addrp;
3615         int ret;
3616
3617         switch (ad->u.net.family) {
3618         case PF_INET:
3619                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3620                 if (ret)
3621                         goto parse_error;
3622                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3623                                        &ad->u.net.v4info.daddr);
3624                 goto okay;
3625
3626 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3627         case PF_INET6:
3628                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3629                 if (ret)
3630                         goto parse_error;
3631                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3632                                        &ad->u.net.v6info.daddr);
3633                 goto okay;
3634 #endif  /* IPV6 */
3635         default:
3636                 addrp = NULL;
3637                 goto okay;
3638         }
3639
3640 parse_error:
3641         printk(KERN_WARNING
3642                "SELinux: failure in selinux_parse_skb(),"
3643                " unable to parse packet\n");
3644         return ret;
3645
3646 okay:
3647         if (_addrp)
3648                 *_addrp = addrp;
3649         return 0;
3650 }
3651
3652 /**
3653  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3654  * @skb: the packet
3655  * @family: protocol family
3656  * @sid: the packet's peer label SID
3657  *
3658  * Description:
3659  * Check the various different forms of network peer labeling and determine
3660  * the peer label/SID for the packet; most of the magic actually occurs in
3661  * the security server function security_net_peersid_cmp().  The function
3662  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3663  * or -EACCES if @sid is invalid due to inconsistencies with the different
3664  * peer labels.
3665  *
3666  */
3667 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3668 {
3669         int err;
3670         u32 xfrm_sid;
3671         u32 nlbl_sid;
3672         u32 nlbl_type;
3673
3674         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3675         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3676
3677         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3678         if (unlikely(err)) {
3679                 printk(KERN_WARNING
3680                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3681                        " unable to determine packet's peer label\n");
3682                 return -EACCES;
3683         }
3684
3685         return 0;
3686 }
3687
3688 /* socket security operations */
3689
3690 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3691                                  u16 secclass, u32 *socksid)
3692 {
3693         if (tsec->sockcreate_sid > SECSID_NULL) {
3694                 *socksid = tsec->sockcreate_sid;
3695                 return 0;
3696         }
3697
3698         return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3699                                        socksid);
3700 }
3701
3702 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3703 {
3704         struct sk_security_struct *sksec = sk->sk_security;
3705         struct common_audit_data ad;
3706         u32 tsid = task_sid(task);
3707
3708         if (sksec->sid == SECINITSID_KERNEL)
3709                 return 0;
3710
3711         COMMON_AUDIT_DATA_INIT(&ad, NET);
3712         ad.u.net.sk = sk;
3713
3714         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3715 }
3716
3717 static int selinux_socket_create(int family, int type,
3718                                  int protocol, int kern)
3719 {
3720         const struct task_security_struct *tsec = current_security();
3721         u32 newsid;
3722         u16 secclass;
3723         int rc;
3724
3725         if (kern)
3726                 return 0;
3727
3728         secclass = socket_type_to_security_class(family, type, protocol);
3729         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3730         if (rc)
3731                 return rc;
3732
3733         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3734 }
3735
3736 static int selinux_socket_post_create(struct socket *sock, int family,
3737                                       int type, int protocol, int kern)
3738 {
3739         const struct task_security_struct *tsec = current_security();
3740         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3741         struct sk_security_struct *sksec;
3742         int err = 0;
3743
3744         isec->sclass = socket_type_to_security_class(family, type, protocol);
3745
3746         if (kern)
3747                 isec->sid = SECINITSID_KERNEL;
3748         else {
3749                 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3750                 if (err)
3751                         return err;
3752         }
3753
3754         isec->initialized = 1;
3755
3756         if (sock->sk) {
3757                 sksec = sock->sk->sk_security;
3758                 sksec->sid = isec->sid;
3759                 sksec->sclass = isec->sclass;
3760                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3761         }
3762
3763         return err;
3764 }
3765
3766 /* Range of port numbers used to automatically bind.
3767    Need to determine whether we should perform a name_bind
3768    permission check between the socket and the port number. */
3769
3770 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3771 {
3772         struct sock *sk = sock->sk;
3773         u16 family;
3774         int err;
3775
3776         err = sock_has_perm(current, sk, SOCKET__BIND);
3777         if (err)
3778                 goto out;
3779
3780         /*
3781          * If PF_INET or PF_INET6, check name_bind permission for the port.
3782          * Multiple address binding for SCTP is not supported yet: we just
3783          * check the first address now.
3784          */
3785         family = sk->sk_family;
3786         if (family == PF_INET || family == PF_INET6) {
3787                 char *addrp;
3788                 struct sk_security_struct *sksec = sk->sk_security;
3789                 struct common_audit_data ad;
3790                 struct sockaddr_in *addr4 = NULL;
3791                 struct sockaddr_in6 *addr6 = NULL;
3792                 unsigned short snum;
3793                 u32 sid, node_perm;
3794
3795                 if (family == PF_INET) {
3796                         addr4 = (struct sockaddr_in *)address;
3797                         snum = ntohs(addr4->sin_port);
3798                         addrp = (char *)&addr4->sin_addr.s_addr;
3799                 } else {
3800                         addr6 = (struct sockaddr_in6 *)address;
3801                         snum = ntohs(addr6->sin6_port);
3802                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3803                 }
3804
3805                 if (snum) {
3806                         int low, high;
3807
3808                         inet_get_local_port_range(&low, &high);
3809
3810                         if (snum < max(PROT_SOCK, low) || snum > high) {
3811                                 err = sel_netport_sid(sk->sk_protocol,
3812                                                       snum, &sid);
3813                                 if (err)
3814                                         goto out;
3815                                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3816                                 ad.u.net.sport = htons(snum);
3817                                 ad.u.net.family = family;
3818                                 err = avc_has_perm(sksec->sid, sid,
3819                                                    sksec->sclass,
3820                                                    SOCKET__NAME_BIND, &ad);
3821                                 if (err)
3822                                         goto out;
3823                         }
3824                 }
3825
3826                 switch (sksec->sclass) {
3827                 case SECCLASS_TCP_SOCKET:
3828                         node_perm = TCP_SOCKET__NODE_BIND;
3829                         break;
3830
3831                 case SECCLASS_UDP_SOCKET:
3832                         node_perm = UDP_SOCKET__NODE_BIND;
3833                         break;
3834
3835                 case SECCLASS_DCCP_SOCKET:
3836                         node_perm = DCCP_SOCKET__NODE_BIND;
3837                         break;
3838
3839                 default:
3840                         node_perm = RAWIP_SOCKET__NODE_BIND;
3841                         break;
3842                 }
3843
3844                 err = sel_netnode_sid(addrp, family, &sid);
3845                 if (err)
3846                         goto out;
3847
3848                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3849                 ad.u.net.sport = htons(snum);
3850                 ad.u.net.family = family;
3851
3852                 if (family == PF_INET)
3853                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3854                 else
3855                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3856
3857                 err = avc_has_perm(sksec->sid, sid,
3858                                    sksec->sclass, node_perm, &ad);
3859                 if (err)
3860                         goto out;
3861         }
3862 out:
3863         return err;
3864 }
3865
3866 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3867 {
3868         struct sock *sk = sock->sk;
3869         struct sk_security_struct *sksec = sk->sk_security;
3870         int err;
3871
3872         err = sock_has_perm(current, sk, SOCKET__CONNECT);
3873         if (err)
3874                 return err;
3875
3876         /*
3877          * If a TCP or DCCP socket, check name_connect permission for the port.
3878          */
3879         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3880             sksec->sclass == SECCLASS_DCCP_SOCKET) {
3881                 struct common_audit_data ad;
3882                 struct sockaddr_in *addr4 = NULL;
3883                 struct sockaddr_in6 *addr6 = NULL;
3884                 unsigned short snum;
3885                 u32 sid, perm;
3886
3887                 if (sk->sk_family == PF_INET) {
3888                         addr4 = (struct sockaddr_in *)address;
3889                         if (addrlen < sizeof(struct sockaddr_in))
3890                                 return -EINVAL;
3891                         snum = ntohs(addr4->sin_port);
3892                 } else {
3893                         addr6 = (struct sockaddr_in6 *)address;
3894                         if (addrlen < SIN6_LEN_RFC2133)
3895                                 return -EINVAL;
3896                         snum = ntohs(addr6->sin6_port);
3897                 }
3898
3899                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3900                 if (err)
3901                         goto out;
3902
3903                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3904                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3905
3906                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3907                 ad.u.net.dport = htons(snum);
3908                 ad.u.net.family = sk->sk_family;
3909                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3910                 if (err)
3911                         goto out;
3912         }
3913
3914         err = selinux_netlbl_socket_connect(sk, address);
3915
3916 out:
3917         return err;
3918 }
3919
3920 static int selinux_socket_listen(struct socket *sock, int backlog)
3921 {
3922         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3923 }
3924
3925 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3926 {
3927         int err;
3928         struct inode_security_struct *isec;
3929         struct inode_security_struct *newisec;
3930
3931         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3932         if (err)
3933                 return err;
3934
3935         newisec = SOCK_INODE(newsock)->i_security;
3936
3937         isec = SOCK_INODE(sock)->i_security;
3938         newisec->sclass = isec->sclass;
3939         newisec->sid = isec->sid;
3940         newisec->initialized = 1;
3941
3942         return 0;
3943 }
3944
3945 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3946                                   int size)
3947 {
3948         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3949 }
3950
3951 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3952                                   int size, int flags)
3953 {
3954         return sock_has_perm(current, sock->sk, SOCKET__READ);
3955 }
3956
3957 static int selinux_socket_getsockname(struct socket *sock)
3958 {
3959         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3960 }
3961
3962 static int selinux_socket_getpeername(struct socket *sock)
3963 {
3964         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3965 }
3966
3967 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3968 {
3969         int err;
3970
3971         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3972         if (err)
3973                 return err;
3974
3975         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3976 }
3977
3978 static int selinux_socket_getsockopt(struct socket *sock, int level,
3979                                      int optname)
3980 {
3981         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
3982 }
3983
3984 static int selinux_socket_shutdown(struct socket *sock, int how)
3985 {
3986         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
3987 }
3988
3989 static int selinux_socket_unix_stream_connect(struct sock *sock,
3990                                               struct sock *other,
3991                                               struct sock *newsk)
3992 {
3993         struct sk_security_struct *sksec_sock = sock->sk_security;
3994         struct sk_security_struct *sksec_other = other->sk_security;
3995         struct sk_security_struct *sksec_new = newsk->sk_security;
3996         struct common_audit_data ad;
3997         int err;
3998
3999         COMMON_AUDIT_DATA_INIT(&ad, NET);
4000         ad.u.net.sk = other;
4001
4002         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4003                            sksec_other->sclass,
4004                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4005         if (err)
4006                 return err;
4007
4008         /* server child socket */
4009         sksec_new->peer_sid = sksec_sock->sid;
4010         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4011                                     &sksec_new->sid);
4012         if (err)
4013                 return err;
4014
4015         /* connecting socket */
4016         sksec_sock->peer_sid = sksec_new->sid;
4017
4018         return 0;
4019 }
4020
4021 static int selinux_socket_unix_may_send(struct socket *sock,
4022                                         struct socket *other)
4023 {
4024         struct sk_security_struct *ssec = sock->sk->sk_security;
4025         struct sk_security_struct *osec = other->sk->sk_security;
4026         struct common_audit_data ad;
4027
4028         COMMON_AUDIT_DATA_INIT(&ad, NET);
4029         ad.u.net.sk = other->sk;
4030
4031         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4032                             &ad);
4033 }
4034
4035 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4036                                     u32 peer_sid,
4037                                     struct common_audit_data *ad)
4038 {
4039         int err;
4040         u32 if_sid;
4041         u32 node_sid;
4042
4043         err = sel_netif_sid(ifindex, &if_sid);
4044         if (err)
4045                 return err;
4046         err = avc_has_perm(peer_sid, if_sid,
4047                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4048         if (err)
4049                 return err;
4050
4051         err = sel_netnode_sid(addrp, family, &node_sid);
4052         if (err)
4053                 return err;
4054         return avc_has_perm(peer_sid, node_sid,
4055                             SECCLASS_NODE, NODE__RECVFROM, ad);
4056 }
4057
4058 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4059                                        u16 family)
4060 {
4061         int err = 0;
4062         struct sk_security_struct *sksec = sk->sk_security;
4063         u32 sk_sid = sksec->sid;
4064         struct common_audit_data ad;
4065         char *addrp;
4066
4067         COMMON_AUDIT_DATA_INIT(&ad, NET);
4068         ad.u.net.netif = skb->skb_iif;
4069         ad.u.net.family = family;
4070         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4071         if (err)
4072                 return err;
4073
4074         if (selinux_secmark_enabled()) {
4075                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4076                                    PACKET__RECV, &ad);
4077                 if (err)
4078                         return err;
4079         }
4080
4081         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4082         if (err)
4083                 return err;
4084         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4085
4086         return err;
4087 }
4088
4089 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4090 {
4091         int err;
4092         struct sk_security_struct *sksec = sk->sk_security;
4093         u16 family = sk->sk_family;
4094         u32 sk_sid = sksec->sid;
4095         struct common_audit_data ad;
4096         char *addrp;
4097         u8 secmark_active;
4098         u8 peerlbl_active;
4099
4100         if (family != PF_INET && family != PF_INET6)
4101                 return 0;
4102
4103         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4104         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4105                 family = PF_INET;
4106
4107         /* If any sort of compatibility mode is enabled then handoff processing
4108          * to the selinux_sock_rcv_skb_compat() function to deal with the
4109          * special handling.  We do this in an attempt to keep this function
4110          * as fast and as clean as possible. */
4111         if (!selinux_policycap_netpeer)
4112                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4113
4114         secmark_active = selinux_secmark_enabled();
4115         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4116         if (!secmark_active && !peerlbl_active)
4117                 return 0;
4118
4119         COMMON_AUDIT_DATA_INIT(&ad, NET);
4120         ad.u.net.netif = skb->skb_iif;
4121         ad.u.net.family = family;
4122         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4123         if (err)
4124                 return err;
4125
4126         if (peerlbl_active) {
4127                 u32 peer_sid;
4128
4129                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4130                 if (err)
4131                         return err;
4132                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4133                                                peer_sid, &ad);
4134                 if (err) {
4135                         selinux_netlbl_err(skb, err, 0);
4136                         return err;
4137                 }
4138                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4139                                    PEER__RECV, &ad);
4140                 if (err)
4141                         selinux_netlbl_err(skb, err, 0);
4142         }
4143
4144         if (secmark_active) {
4145                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4146                                    PACKET__RECV, &ad);
4147                 if (err)
4148                         return err;
4149         }
4150
4151         return err;
4152 }
4153
4154 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4155                                             int __user *optlen, unsigned len)
4156 {
4157         int err = 0;
4158         char *scontext;
4159         u32 scontext_len;
4160         struct sk_security_struct *sksec = sock->sk->sk_security;
4161         u32 peer_sid = SECSID_NULL;
4162
4163         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4164             sksec->sclass == SECCLASS_TCP_SOCKET)
4165                 peer_sid = sksec->peer_sid;
4166         if (peer_sid == SECSID_NULL)
4167                 return -ENOPROTOOPT;
4168
4169         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4170         if (err)
4171                 return err;
4172
4173         if (scontext_len > len) {
4174                 err = -ERANGE;
4175                 goto out_len;
4176         }
4177
4178         if (copy_to_user(optval, scontext, scontext_len))
4179                 err = -EFAULT;
4180
4181 out_len:
4182         if (put_user(scontext_len, optlen))
4183                 err = -EFAULT;
4184         kfree(scontext);
4185         return err;
4186 }
4187
4188 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4189 {
4190         u32 peer_secid = SECSID_NULL;
4191         u16 family;
4192
4193         if (skb && skb->protocol == htons(ETH_P_IP))
4194                 family = PF_INET;
4195         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4196                 family = PF_INET6;
4197         else if (sock)
4198                 family = sock->sk->sk_family;
4199         else
4200                 goto out;
4201
4202         if (sock && family == PF_UNIX)
4203                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4204         else if (skb)
4205                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4206
4207 out:
4208         *secid = peer_secid;
4209         if (peer_secid == SECSID_NULL)
4210                 return -EINVAL;
4211         return 0;
4212 }
4213
4214 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4215 {
4216         struct sk_security_struct *sksec;
4217
4218         sksec = kzalloc(sizeof(*sksec), priority);
4219         if (!sksec)
4220                 return -ENOMEM;
4221
4222         sksec->peer_sid = SECINITSID_UNLABELED;
4223         sksec->sid = SECINITSID_UNLABELED;
4224         selinux_netlbl_sk_security_reset(sksec);
4225         sk->sk_security = sksec;
4226
4227         return 0;
4228 }
4229
4230 static void selinux_sk_free_security(struct sock *sk)
4231 {
4232         struct sk_security_struct *sksec = sk->sk_security;
4233
4234         sk->sk_security = NULL;
4235         selinux_netlbl_sk_security_free(sksec);
4236         kfree(sksec);
4237 }
4238
4239 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4240 {
4241         struct sk_security_struct *sksec = sk->sk_security;
4242         struct sk_security_struct *newsksec = newsk->sk_security;
4243
4244         newsksec->sid = sksec->sid;
4245         newsksec->peer_sid = sksec->peer_sid;
4246         newsksec->sclass = sksec->sclass;
4247
4248         selinux_netlbl_sk_security_reset(newsksec);
4249 }
4250
4251 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4252 {
4253         if (!sk)
4254                 *secid = SECINITSID_ANY_SOCKET;
4255         else {
4256                 struct sk_security_struct *sksec = sk->sk_security;
4257
4258                 *secid = sksec->sid;
4259         }
4260 }
4261
4262 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4263 {
4264         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4265         struct sk_security_struct *sksec = sk->sk_security;
4266
4267         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4268             sk->sk_family == PF_UNIX)
4269                 isec->sid = sksec->sid;
4270         sksec->sclass = isec->sclass;
4271 }
4272
4273 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4274                                      struct request_sock *req)
4275 {
4276         struct sk_security_struct *sksec = sk->sk_security;
4277         int err;
4278         u16 family = sk->sk_family;
4279         u32 newsid;
4280         u32 peersid;
4281
4282         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4283         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4284                 family = PF_INET;
4285
4286         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4287         if (err)
4288                 return err;
4289         if (peersid == SECSID_NULL) {
4290                 req->secid = sksec->sid;
4291                 req->peer_secid = SECSID_NULL;
4292         } else {
4293                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4294                 if (err)
4295                         return err;
4296                 req->secid = newsid;
4297                 req->peer_secid = peersid;
4298         }
4299
4300         return selinux_netlbl_inet_conn_request(req, family);
4301 }
4302
4303 static void selinux_inet_csk_clone(struct sock *newsk,
4304                                    const struct request_sock *req)
4305 {
4306         struct sk_security_struct *newsksec = newsk->sk_security;
4307
4308         newsksec->sid = req->secid;
4309         newsksec->peer_sid = req->peer_secid;
4310         /* NOTE: Ideally, we should also get the isec->sid for the
4311            new socket in sync, but we don't have the isec available yet.
4312            So we will wait until sock_graft to do it, by which
4313            time it will have been created and available. */
4314
4315         /* We don't need to take any sort of lock here as we are the only
4316          * thread with access to newsksec */
4317         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4318 }
4319
4320 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4321 {
4322         u16 family = sk->sk_family;
4323         struct sk_security_struct *sksec = sk->sk_security;
4324
4325         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4326         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4327                 family = PF_INET;
4328
4329         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4330 }
4331
4332 static int selinux_secmark_relabel_packet(u32 sid)
4333 {
4334         const struct task_security_struct *__tsec;
4335         u32 tsid;
4336
4337         __tsec = current_security();
4338         tsid = __tsec->sid;
4339
4340         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4341 }
4342
4343 static void selinux_secmark_refcount_inc(void)
4344 {
4345         atomic_inc(&selinux_secmark_refcount);
4346 }
4347
4348 static void selinux_secmark_refcount_dec(void)
4349 {
4350         atomic_dec(&selinux_secmark_refcount);
4351 }
4352
4353 static void selinux_req_classify_flow(const struct request_sock *req,
4354                                       struct flowi *fl)
4355 {
4356         fl->flowi_secid = req->secid;
4357 }
4358
4359 static int selinux_tun_dev_create(void)
4360 {
4361         u32 sid = current_sid();
4362
4363         /* we aren't taking into account the "sockcreate" SID since the socket
4364          * that is being created here is not a socket in the traditional sense,
4365          * instead it is a private sock, accessible only to the kernel, and
4366          * representing a wide range of network traffic spanning multiple
4367          * connections unlike traditional sockets - check the TUN driver to
4368          * get a better understanding of why this socket is special */
4369
4370         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4371                             NULL);
4372 }
4373
4374 static void selinux_tun_dev_post_create(struct sock *sk)
4375 {
4376         struct sk_security_struct *sksec = sk->sk_security;
4377
4378         /* we don't currently perform any NetLabel based labeling here and it
4379          * isn't clear that we would want to do so anyway; while we could apply
4380          * labeling without the support of the TUN user the resulting labeled
4381          * traffic from the other end of the connection would almost certainly
4382          * cause confusion to the TUN user that had no idea network labeling
4383          * protocols were being used */
4384
4385         /* see the comments in selinux_tun_dev_create() about why we don't use
4386          * the sockcreate SID here */
4387
4388         sksec->sid = current_sid();
4389         sksec->sclass = SECCLASS_TUN_SOCKET;
4390 }
4391
4392 static int selinux_tun_dev_attach(struct sock *sk)
4393 {
4394         struct sk_security_struct *sksec = sk->sk_security;
4395         u32 sid = current_sid();
4396         int err;
4397
4398         err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4399                            TUN_SOCKET__RELABELFROM, NULL);
4400         if (err)
4401                 return err;
4402         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4403                            TUN_SOCKET__RELABELTO, NULL);
4404         if (err)
4405                 return err;
4406
4407         sksec->sid = sid;
4408
4409         return 0;
4410 }
4411
4412 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4413 {
4414         int err = 0;
4415         u32 perm;
4416         struct nlmsghdr *nlh;
4417         struct sk_security_struct *sksec = sk->sk_security;
4418
4419         if (skb->len < NLMSG_SPACE(0)) {
4420                 err = -EINVAL;
4421                 goto out;
4422         }
4423         nlh = nlmsg_hdr(skb);
4424
4425         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4426         if (err) {
4427                 if (err == -EINVAL) {
4428                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4429                                   "SELinux:  unrecognized netlink message"
4430                                   " type=%hu for sclass=%hu\n",
4431                                   nlh->nlmsg_type, sksec->sclass);
4432                         if (!selinux_enforcing || security_get_allow_unknown())
4433                                 err = 0;
4434                 }
4435
4436                 /* Ignore */
4437                 if (err == -ENOENT)
4438                         err = 0;
4439                 goto out;
4440         }
4441
4442         err = sock_has_perm(current, sk, perm);
4443 out:
4444         return err;
4445 }
4446
4447 #ifdef CONFIG_NETFILTER
4448
4449 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4450                                        u16 family)
4451 {
4452         int err;
4453         char *addrp;
4454         u32 peer_sid;
4455         struct common_audit_data ad;
4456         u8 secmark_active;
4457         u8 netlbl_active;
4458         u8 peerlbl_active;
4459
4460         if (!selinux_policycap_netpeer)
4461                 return NF_ACCEPT;
4462
4463         secmark_active = selinux_secmark_enabled();
4464         netlbl_active = netlbl_enabled();
4465         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4466         if (!secmark_active && !peerlbl_active)
4467                 return NF_ACCEPT;
4468
4469         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4470                 return NF_DROP;
4471
4472         COMMON_AUDIT_DATA_INIT(&ad, NET);
4473         ad.u.net.netif = ifindex;
4474         ad.u.net.family = family;
4475         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4476                 return NF_DROP;
4477
4478         if (peerlbl_active) {
4479                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4480                                                peer_sid, &ad);
4481                 if (err) {
4482                         selinux_netlbl_err(skb, err, 1);
4483                         return NF_DROP;
4484                 }
4485         }
4486
4487         if (secmark_active)
4488                 if (avc_has_perm(peer_sid, skb->secmark,
4489                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4490                         return NF_DROP;
4491
4492         if (netlbl_active)
4493                 /* we do this in the FORWARD path and not the POST_ROUTING
4494                  * path because we want to make sure we apply the necessary
4495                  * labeling before IPsec is applied so we can leverage AH
4496                  * protection */
4497                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4498                         return NF_DROP;
4499
4500         return NF_ACCEPT;
4501 }
4502
4503 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4504                                          struct sk_buff *skb,
4505                                          const struct net_device *in,
4506                                          const struct net_device *out,
4507                                          int (*okfn)(struct sk_buff *))
4508 {
4509         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4510 }
4511
4512 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4513 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4514                                          struct sk_buff *skb,
4515                                          const struct net_device *in,
4516                                          const struct net_device *out,
4517                                          int (*okfn)(struct sk_buff *))
4518 {
4519         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4520 }
4521 #endif  /* IPV6 */
4522
4523 static unsigned int selinux_ip_output(struct sk_buff *skb,
4524                                       u16 family)
4525 {
4526         u32 sid;
4527
4528         if (!netlbl_enabled())
4529                 return NF_ACCEPT;
4530
4531         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4532          * because we want to make sure we apply the necessary labeling
4533          * before IPsec is applied so we can leverage AH protection */
4534         if (skb->sk) {
4535                 struct sk_security_struct *sksec = skb->sk->sk_security;
4536                 sid = sksec->sid;
4537         } else
4538                 sid = SECINITSID_KERNEL;
4539         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4540                 return NF_DROP;
4541
4542         return NF_ACCEPT;
4543 }
4544
4545 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4546                                         struct sk_buff *skb,
4547                                         const struct net_device *in,
4548                                         const struct net_device *out,
4549                                         int (*okfn)(struct sk_buff *))
4550 {
4551         return selinux_ip_output(skb, PF_INET);
4552 }
4553
4554 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4555                                                 int ifindex,
4556                                                 u16 family)
4557 {
4558         struct sock *sk = skb->sk;
4559         struct sk_security_struct *sksec;
4560         struct common_audit_data ad;
4561         char *addrp;
4562         u8 proto;
4563
4564         if (sk == NULL)
4565                 return NF_ACCEPT;
4566         sksec = sk->sk_security;
4567
4568         COMMON_AUDIT_DATA_INIT(&ad, NET);
4569         ad.u.net.netif = ifindex;
4570         ad.u.net.family = family;
4571         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4572                 return NF_DROP;
4573
4574         if (selinux_secmark_enabled())
4575                 if (avc_has_perm(sksec->sid, skb->secmark,
4576                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4577                         return NF_DROP_ERR(-ECONNREFUSED);
4578
4579         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4580                 return NF_DROP_ERR(-ECONNREFUSED);
4581
4582         return NF_ACCEPT;
4583 }
4584
4585 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4586                                          u16 family)
4587 {
4588         u32 secmark_perm;
4589         u32 peer_sid;
4590         struct sock *sk;
4591         struct common_audit_data ad;
4592         char *addrp;
4593         u8 secmark_active;
4594         u8 peerlbl_active;
4595
4596         /* If any sort of compatibility mode is enabled then handoff processing
4597          * to the selinux_ip_postroute_compat() function to deal with the
4598          * special handling.  We do this in an attempt to keep this function
4599          * as fast and as clean as possible. */
4600         if (!selinux_policycap_netpeer)
4601                 return selinux_ip_postroute_compat(skb, ifindex, family);
4602 #ifdef CONFIG_XFRM
4603         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4604          * packet transformation so allow the packet to pass without any checks
4605          * since we'll have another chance to perform access control checks
4606          * when the packet is on it's final way out.
4607          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4608          *       is NULL, in this case go ahead and apply access control. */
4609         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4610                 return NF_ACCEPT;
4611 #endif
4612         secmark_active = selinux_secmark_enabled();
4613         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4614         if (!secmark_active && !peerlbl_active)
4615                 return NF_ACCEPT;
4616
4617         /* if the packet is being forwarded then get the peer label from the
4618          * packet itself; otherwise check to see if it is from a local
4619          * application or the kernel, if from an application get the peer label
4620          * from the sending socket, otherwise use the kernel's sid */
4621         sk = skb->sk;
4622         if (sk == NULL) {
4623                 if (skb->skb_iif) {
4624                         secmark_perm = PACKET__FORWARD_OUT;
4625                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4626                                 return NF_DROP;
4627                 } else {
4628                         secmark_perm = PACKET__SEND;
4629                         peer_sid = SECINITSID_KERNEL;
4630                 }
4631         } else {
4632                 struct sk_security_struct *sksec = sk->sk_security;
4633                 peer_sid = sksec->sid;
4634                 secmark_perm = PACKET__SEND;
4635         }
4636
4637         COMMON_AUDIT_DATA_INIT(&ad, NET);
4638         ad.u.net.netif = ifindex;
4639         ad.u.net.family = family;
4640         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4641                 return NF_DROP;
4642
4643         if (secmark_active)
4644                 if (avc_has_perm(peer_sid, skb->secmark,
4645                                  SECCLASS_PACKET, secmark_perm, &ad))
4646                         return NF_DROP_ERR(-ECONNREFUSED);
4647
4648         if (peerlbl_active) {
4649                 u32 if_sid;
4650                 u32 node_sid;
4651
4652                 if (sel_netif_sid(ifindex, &if_sid))
4653                         return NF_DROP;
4654                 if (avc_has_perm(peer_sid, if_sid,
4655                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4656                         return NF_DROP_ERR(-ECONNREFUSED);
4657
4658                 if (sel_netnode_sid(addrp, family, &node_sid))
4659                         return NF_DROP;
4660                 if (avc_has_perm(peer_sid, node_sid,
4661                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4662                         return NF_DROP_ERR(-ECONNREFUSED);
4663         }
4664
4665         return NF_ACCEPT;
4666 }
4667
4668 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4669                                            struct sk_buff *skb,
4670                                            const struct net_device *in,
4671                                            const struct net_device *out,
4672                                            int (*okfn)(struct sk_buff *))
4673 {
4674         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4675 }
4676
4677 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4678 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4679                                            struct sk_buff *skb,
4680                                            const struct net_device *in,
4681                                            const struct net_device *out,
4682                                            int (*okfn)(struct sk_buff *))
4683 {
4684         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4685 }
4686 #endif  /* IPV6 */
4687
4688 #endif  /* CONFIG_NETFILTER */
4689
4690 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4691 {
4692         int err;
4693
4694         err = cap_netlink_send(sk, skb);
4695         if (err)
4696                 return err;
4697
4698         return selinux_nlmsg_perm(sk, skb);
4699 }
4700
4701 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4702 {
4703         int err;
4704         struct common_audit_data ad;
4705         u32 sid;
4706
4707         err = cap_netlink_recv(skb, capability);
4708         if (err)
4709                 return err;
4710
4711         COMMON_AUDIT_DATA_INIT(&ad, CAP);
4712         ad.u.cap = capability;
4713
4714         security_task_getsecid(current, &sid);
4715         return avc_has_perm(sid, sid, SECCLASS_CAPABILITY,
4716                             CAP_TO_MASK(capability), &ad);
4717 }
4718
4719 static int ipc_alloc_security(struct task_struct *task,
4720                               struct kern_ipc_perm *perm,
4721                               u16 sclass)
4722 {
4723         struct ipc_security_struct *isec;
4724         u32 sid;
4725
4726         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4727         if (!isec)
4728                 return -ENOMEM;
4729
4730         sid = task_sid(task);
4731         isec->sclass = sclass;
4732         isec->sid = sid;
4733         perm->security = isec;
4734
4735         return 0;
4736 }
4737
4738 static void ipc_free_security(struct kern_ipc_perm *perm)
4739 {
4740         struct ipc_security_struct *isec = perm->security;
4741         perm->security = NULL;
4742         kfree(isec);
4743 }
4744
4745 static int msg_msg_alloc_security(struct msg_msg *msg)
4746 {
4747         struct msg_security_struct *msec;
4748
4749         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4750         if (!msec)
4751                 return -ENOMEM;
4752
4753         msec->sid = SECINITSID_UNLABELED;
4754         msg->security = msec;
4755
4756         return 0;
4757 }
4758
4759 static void msg_msg_free_security(struct msg_msg *msg)
4760 {
4761         struct msg_security_struct *msec = msg->security;
4762
4763         msg->security = NULL;
4764         kfree(msec);
4765 }
4766
4767 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4768                         u32 perms)
4769 {
4770         struct ipc_security_struct *isec;
4771         struct common_audit_data ad;
4772         u32 sid = current_sid();
4773
4774         isec = ipc_perms->security;
4775
4776         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4777         ad.u.ipc_id = ipc_perms->key;
4778
4779         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4780 }
4781
4782 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4783 {
4784         return msg_msg_alloc_security(msg);
4785 }
4786
4787 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4788 {
4789         msg_msg_free_security(msg);
4790 }
4791
4792 /* message queue security operations */
4793 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4794 {
4795         struct ipc_security_struct *isec;
4796         struct common_audit_data ad;
4797         u32 sid = current_sid();
4798         int rc;
4799
4800         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4801         if (rc)
4802                 return rc;
4803
4804         isec = msq->q_perm.security;
4805
4806         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4807         ad.u.ipc_id = msq->q_perm.key;
4808
4809         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4810                           MSGQ__CREATE, &ad);
4811         if (rc) {
4812                 ipc_free_security(&msq->q_perm);
4813                 return rc;
4814         }
4815         return 0;
4816 }
4817
4818 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4819 {
4820         ipc_free_security(&msq->q_perm);
4821 }
4822
4823 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4824 {
4825         struct ipc_security_struct *isec;
4826         struct common_audit_data ad;
4827         u32 sid = current_sid();
4828
4829         isec = msq->q_perm.security;
4830
4831         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4832         ad.u.ipc_id = msq->q_perm.key;
4833
4834         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4835                             MSGQ__ASSOCIATE, &ad);
4836 }
4837
4838 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4839 {
4840         int err;
4841         int perms;
4842
4843         switch (cmd) {
4844         case IPC_INFO:
4845         case MSG_INFO:
4846                 /* No specific object, just general system-wide information. */
4847                 return task_has_system(current, SYSTEM__IPC_INFO);
4848         case IPC_STAT:
4849         case MSG_STAT:
4850                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4851                 break;
4852         case IPC_SET:
4853                 perms = MSGQ__SETATTR;
4854                 break;
4855         case IPC_RMID:
4856                 perms = MSGQ__DESTROY;
4857                 break;
4858         default:
4859                 return 0;
4860         }
4861
4862         err = ipc_has_perm(&msq->q_perm, perms);
4863         return err;
4864 }
4865
4866 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4867 {
4868         struct ipc_security_struct *isec;
4869         struct msg_security_struct *msec;
4870         struct common_audit_data ad;
4871         u32 sid = current_sid();
4872         int rc;
4873
4874         isec = msq->q_perm.security;
4875         msec = msg->security;
4876
4877         /*
4878          * First time through, need to assign label to the message
4879          */
4880         if (msec->sid == SECINITSID_UNLABELED) {
4881                 /*
4882                  * Compute new sid based on current process and
4883                  * message queue this message will be stored in
4884                  */
4885                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4886                                              NULL, &msec->sid);
4887                 if (rc)
4888                         return rc;
4889         }
4890
4891         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4892         ad.u.ipc_id = msq->q_perm.key;
4893
4894         /* Can this process write to the queue? */
4895         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4896                           MSGQ__WRITE, &ad);
4897         if (!rc)
4898                 /* Can this process send the message */
4899                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4900                                   MSG__SEND, &ad);
4901         if (!rc)
4902                 /* Can the message be put in the queue? */
4903                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4904                                   MSGQ__ENQUEUE, &ad);
4905
4906         return rc;
4907 }
4908
4909 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4910                                     struct task_struct *target,
4911                                     long type, int mode)
4912 {
4913         struct ipc_security_struct *isec;
4914         struct msg_security_struct *msec;
4915         struct common_audit_data ad;
4916         u32 sid = task_sid(target);
4917         int rc;
4918
4919         isec = msq->q_perm.security;
4920         msec = msg->security;
4921
4922         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4923         ad.u.ipc_id = msq->q_perm.key;
4924
4925         rc = avc_has_perm(sid, isec->sid,
4926                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4927         if (!rc)
4928                 rc = avc_has_perm(sid, msec->sid,
4929                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4930         return rc;
4931 }
4932
4933 /* Shared Memory security operations */
4934 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4935 {
4936         struct ipc_security_struct *isec;
4937         struct common_audit_data ad;
4938         u32 sid = current_sid();
4939         int rc;
4940
4941         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4942         if (rc)
4943                 return rc;
4944
4945         isec = shp->shm_perm.security;
4946
4947         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4948         ad.u.ipc_id = shp->shm_perm.key;
4949
4950         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4951                           SHM__CREATE, &ad);
4952         if (rc) {
4953                 ipc_free_security(&shp->shm_perm);
4954                 return rc;
4955         }
4956         return 0;
4957 }
4958
4959 static void selinux_shm_free_security(struct shmid_kernel *shp)
4960 {
4961         ipc_free_security(&shp->shm_perm);
4962 }
4963
4964 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4965 {
4966         struct ipc_security_struct *isec;
4967         struct common_audit_data ad;
4968         u32 sid = current_sid();
4969
4970         isec = shp->shm_perm.security;
4971
4972         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4973         ad.u.ipc_id = shp->shm_perm.key;
4974
4975         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4976                             SHM__ASSOCIATE, &ad);
4977 }
4978
4979 /* Note, at this point, shp is locked down */
4980 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
4981 {
4982         int perms;
4983         int err;
4984
4985         switch (cmd) {
4986         case IPC_INFO:
4987         case SHM_INFO:
4988                 /* No specific object, just general system-wide information. */
4989                 return task_has_system(current, SYSTEM__IPC_INFO);
4990         case IPC_STAT:
4991         case SHM_STAT:
4992                 perms = SHM__GETATTR | SHM__ASSOCIATE;
4993                 break;
4994         case IPC_SET:
4995                 perms = SHM__SETATTR;
4996                 break;
4997         case SHM_LOCK:
4998         case SHM_UNLOCK:
4999                 perms = SHM__LOCK;
5000                 break;
5001         case IPC_RMID:
5002                 perms = SHM__DESTROY;
5003                 break;
5004         default:
5005                 return 0;
5006         }
5007
5008         err = ipc_has_perm(&shp->shm_perm, perms);
5009         return err;
5010 }
5011
5012 static int selinux_shm_shmat(struct shmid_kernel *shp,
5013                              char __user *shmaddr, int shmflg)
5014 {
5015         u32 perms;
5016
5017         if (shmflg & SHM_RDONLY)
5018                 perms = SHM__READ;
5019         else
5020                 perms = SHM__READ | SHM__WRITE;
5021
5022         return ipc_has_perm(&shp->shm_perm, perms);
5023 }
5024
5025 /* Semaphore security operations */
5026 static int selinux_sem_alloc_security(struct sem_array *sma)
5027 {
5028         struct ipc_security_struct *isec;
5029         struct common_audit_data ad;
5030         u32 sid = current_sid();
5031         int rc;
5032
5033         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5034         if (rc)
5035                 return rc;
5036
5037         isec = sma->sem_perm.security;
5038
5039         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5040         ad.u.ipc_id = sma->sem_perm.key;
5041
5042         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5043                           SEM__CREATE, &ad);
5044         if (rc) {
5045                 ipc_free_security(&sma->sem_perm);
5046                 return rc;
5047         }
5048         return 0;
5049 }
5050
5051 static void selinux_sem_free_security(struct sem_array *sma)
5052 {
5053         ipc_free_security(&sma->sem_perm);
5054 }
5055
5056 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5057 {
5058         struct ipc_security_struct *isec;
5059         struct common_audit_data ad;
5060         u32 sid = current_sid();
5061
5062         isec = sma->sem_perm.security;
5063
5064         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5065         ad.u.ipc_id = sma->sem_perm.key;
5066
5067         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5068                             SEM__ASSOCIATE, &ad);
5069 }
5070
5071 /* Note, at this point, sma is locked down */
5072 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5073 {
5074         int err;
5075         u32 perms;
5076
5077         switch (cmd) {
5078         case IPC_INFO:
5079         case SEM_INFO:
5080                 /* No specific object, just general system-wide information. */
5081                 return task_has_system(current, SYSTEM__IPC_INFO);
5082         case GETPID:
5083         case GETNCNT:
5084         case GETZCNT:
5085                 perms = SEM__GETATTR;
5086                 break;
5087         case GETVAL:
5088         case GETALL:
5089                 perms = SEM__READ;
5090                 break;
5091         case SETVAL:
5092         case SETALL:
5093                 perms = SEM__WRITE;
5094                 break;
5095         case IPC_RMID:
5096                 perms = SEM__DESTROY;
5097                 break;
5098         case IPC_SET:
5099                 perms = SEM__SETATTR;
5100                 break;
5101         case IPC_STAT:
5102         case SEM_STAT:
5103                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5104                 break;
5105         default:
5106                 return 0;
5107         }
5108
5109         err = ipc_has_perm(&sma->sem_perm, perms);
5110         return err;
5111 }
5112
5113 static int selinux_sem_semop(struct sem_array *sma,
5114                              struct sembuf *sops, unsigned nsops, int alter)
5115 {
5116         u32 perms;
5117
5118         if (alter)
5119                 perms = SEM__READ | SEM__WRITE;
5120         else
5121                 perms = SEM__READ;
5122
5123         return ipc_has_perm(&sma->sem_perm, perms);
5124 }
5125
5126 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5127 {
5128         u32 av = 0;
5129
5130         av = 0;
5131         if (flag & S_IRUGO)
5132                 av |= IPC__UNIX_READ;
5133         if (flag & S_IWUGO)
5134                 av |= IPC__UNIX_WRITE;
5135
5136         if (av == 0)
5137                 return 0;
5138
5139         return ipc_has_perm(ipcp, av);
5140 }
5141
5142 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5143 {
5144         struct ipc_security_struct *isec = ipcp->security;
5145         *secid = isec->sid;
5146 }
5147
5148 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5149 {
5150         if (inode)
5151                 inode_doinit_with_dentry(inode, dentry);
5152 }
5153
5154 static int selinux_getprocattr(struct task_struct *p,
5155                                char *name, char **value)
5156 {
5157         const struct task_security_struct *__tsec;
5158         u32 sid;
5159         int error;
5160         unsigned len;
5161
5162         if (current != p) {
5163                 error = current_has_perm(p, PROCESS__GETATTR);
5164                 if (error)
5165                         return error;
5166         }
5167
5168         rcu_read_lock();
5169         __tsec = __task_cred(p)->security;
5170
5171         if (!strcmp(name, "current"))
5172                 sid = __tsec->sid;
5173         else if (!strcmp(name, "prev"))
5174                 sid = __tsec->osid;
5175         else if (!strcmp(name, "exec"))
5176                 sid = __tsec->exec_sid;
5177         else if (!strcmp(name, "fscreate"))
5178                 sid = __tsec->create_sid;
5179         else if (!strcmp(name, "keycreate"))
5180                 sid = __tsec->keycreate_sid;
5181         else if (!strcmp(name, "sockcreate"))
5182                 sid = __tsec->sockcreate_sid;
5183         else
5184                 goto invalid;
5185         rcu_read_unlock();
5186
5187         if (!sid)
5188                 return 0;
5189
5190         error = security_sid_to_context(sid, value, &len);
5191         if (error)
5192                 return error;
5193         return len;
5194
5195 invalid:
5196         rcu_read_unlock();
5197         return -EINVAL;
5198 }
5199
5200 static int selinux_setprocattr(struct task_struct *p,
5201                                char *name, void *value, size_t size)
5202 {
5203         struct task_security_struct *tsec;
5204         struct task_struct *tracer;
5205         struct cred *new;
5206         u32 sid = 0, ptsid;
5207         int error;
5208         char *str = value;
5209
5210         if (current != p) {
5211                 /* SELinux only allows a process to change its own
5212                    security attributes. */
5213                 return -EACCES;
5214         }
5215
5216         /*
5217          * Basic control over ability to set these attributes at all.
5218          * current == p, but we'll pass them separately in case the
5219          * above restriction is ever removed.
5220          */
5221         if (!strcmp(name, "exec"))
5222                 error = current_has_perm(p, PROCESS__SETEXEC);
5223         else if (!strcmp(name, "fscreate"))
5224                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5225         else if (!strcmp(name, "keycreate"))
5226                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5227         else if (!strcmp(name, "sockcreate"))
5228                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5229         else if (!strcmp(name, "current"))
5230                 error = current_has_perm(p, PROCESS__SETCURRENT);
5231         else
5232                 error = -EINVAL;
5233         if (error)
5234                 return error;
5235
5236         /* Obtain a SID for the context, if one was specified. */
5237         if (size && str[1] && str[1] != '\n') {
5238                 if (str[size-1] == '\n') {
5239                         str[size-1] = 0;
5240                         size--;
5241                 }
5242                 error = security_context_to_sid(value, size, &sid);
5243                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5244                         if (!capable(CAP_MAC_ADMIN))
5245                                 return error;
5246                         error = security_context_to_sid_force(value, size,
5247                                                               &sid);
5248                 }
5249                 if (error)
5250                         return error;
5251         }
5252
5253         new = prepare_creds();
5254         if (!new)
5255                 return -ENOMEM;
5256
5257         /* Permission checking based on the specified context is
5258            performed during the actual operation (execve,
5259            open/mkdir/...), when we know the full context of the
5260            operation.  See selinux_bprm_set_creds for the execve
5261            checks and may_create for the file creation checks. The
5262            operation will then fail if the context is not permitted. */
5263         tsec = new->security;
5264         if (!strcmp(name, "exec")) {
5265                 tsec->exec_sid = sid;
5266         } else if (!strcmp(name, "fscreate")) {
5267                 tsec->create_sid = sid;
5268         } else if (!strcmp(name, "keycreate")) {
5269                 error = may_create_key(sid, p);
5270                 if (error)
5271                         goto abort_change;
5272                 tsec->keycreate_sid = sid;
5273         } else if (!strcmp(name, "sockcreate")) {
5274                 tsec->sockcreate_sid = sid;
5275         } else if (!strcmp(name, "current")) {
5276                 error = -EINVAL;
5277                 if (sid == 0)
5278                         goto abort_change;
5279
5280                 /* Only allow single threaded processes to change context */
5281                 error = -EPERM;
5282                 if (!current_is_single_threaded()) {
5283                         error = security_bounded_transition(tsec->sid, sid);
5284                         if (error)
5285                                 goto abort_change;
5286                 }
5287
5288                 /* Check permissions for the transition. */
5289                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5290                                      PROCESS__DYNTRANSITION, NULL);
5291                 if (error)
5292                         goto abort_change;
5293
5294                 /* Check for ptracing, and update the task SID if ok.
5295                    Otherwise, leave SID unchanged and fail. */
5296                 ptsid = 0;
5297                 task_lock(p);
5298                 tracer = tracehook_tracer_task(p);
5299                 if (tracer)
5300                         ptsid = task_sid(tracer);
5301                 task_unlock(p);
5302
5303                 if (tracer) {
5304                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5305                                              PROCESS__PTRACE, NULL);
5306                         if (error)
5307                                 goto abort_change;
5308                 }
5309
5310                 tsec->sid = sid;
5311         } else {
5312                 error = -EINVAL;
5313                 goto abort_change;
5314         }
5315
5316         commit_creds(new);
5317         return size;
5318
5319 abort_change:
5320         abort_creds(new);
5321         return error;
5322 }
5323
5324 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5325 {
5326         return security_sid_to_context(secid, secdata, seclen);
5327 }
5328
5329 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5330 {
5331         return security_context_to_sid(secdata, seclen, secid);
5332 }
5333
5334 static void selinux_release_secctx(char *secdata, u32 seclen)
5335 {
5336         kfree(secdata);
5337 }
5338
5339 /*
5340  *      called with inode->i_mutex locked
5341  */
5342 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5343 {
5344         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5345 }
5346
5347 /*
5348  *      called with inode->i_mutex locked
5349  */
5350 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5351 {
5352         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5353 }
5354
5355 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5356 {
5357         int len = 0;
5358         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5359                                                 ctx, true);
5360         if (len < 0)
5361                 return len;
5362         *ctxlen = len;
5363         return 0;
5364 }
5365 #ifdef CONFIG_KEYS
5366
5367 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5368                              unsigned long flags)
5369 {
5370         const struct task_security_struct *tsec;
5371         struct key_security_struct *ksec;
5372
5373         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5374         if (!ksec)
5375                 return -ENOMEM;
5376
5377         tsec = cred->security;
5378         if (tsec->keycreate_sid)
5379                 ksec->sid = tsec->keycreate_sid;
5380         else
5381                 ksec->sid = tsec->sid;
5382
5383         k->security = ksec;
5384         return 0;
5385 }
5386
5387 static void selinux_key_free(struct key *k)
5388 {
5389         struct key_security_struct *ksec = k->security;
5390
5391         k->security = NULL;
5392         kfree(ksec);
5393 }
5394
5395 static int selinux_key_permission(key_ref_t key_ref,
5396                                   const struct cred *cred,
5397                                   key_perm_t perm)
5398 {
5399         struct key *key;
5400         struct key_security_struct *ksec;
5401         u32 sid;
5402
5403         /* if no specific permissions are requested, we skip the
5404            permission check. No serious, additional covert channels
5405            appear to be created. */
5406         if (perm == 0)
5407                 return 0;
5408
5409         sid = cred_sid(cred);
5410
5411         key = key_ref_to_ptr(key_ref);
5412         ksec = key->security;
5413
5414         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5415 }
5416
5417 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5418 {
5419         struct key_security_struct *ksec = key->security;
5420         char *context = NULL;
5421         unsigned len;
5422         int rc;
5423
5424         rc = security_sid_to_context(ksec->sid, &context, &len);
5425         if (!rc)
5426                 rc = len;
5427         *_buffer = context;
5428         return rc;
5429 }
5430
5431 #endif
5432
5433 static struct security_operations selinux_ops = {
5434         .name =                         "selinux",
5435
5436         .ptrace_access_check =          selinux_ptrace_access_check,
5437         .ptrace_traceme =               selinux_ptrace_traceme,
5438         .capget =                       selinux_capget,
5439         .capset =                       selinux_capset,
5440         .capable =                      selinux_capable,
5441         .quotactl =                     selinux_quotactl,
5442         .quota_on =                     selinux_quota_on,
5443         .syslog =                       selinux_syslog,
5444         .vm_enough_memory =             selinux_vm_enough_memory,
5445
5446         .netlink_send =                 selinux_netlink_send,
5447         .netlink_recv =                 selinux_netlink_recv,
5448
5449         .bprm_set_creds =               selinux_bprm_set_creds,
5450         .bprm_committing_creds =        selinux_bprm_committing_creds,
5451         .bprm_committed_creds =         selinux_bprm_committed_creds,
5452         .bprm_secureexec =              selinux_bprm_secureexec,
5453
5454         .sb_alloc_security =            selinux_sb_alloc_security,
5455         .sb_free_security =             selinux_sb_free_security,
5456         .sb_copy_data =                 selinux_sb_copy_data,
5457         .sb_remount =                   selinux_sb_remount,
5458         .sb_kern_mount =                selinux_sb_kern_mount,
5459         .sb_show_options =              selinux_sb_show_options,
5460         .sb_statfs =                    selinux_sb_statfs,
5461         .sb_mount =                     selinux_mount,
5462         .sb_umount =                    selinux_umount,
5463         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5464         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5465         .sb_parse_opts_str =            selinux_parse_opts_str,
5466
5467
5468         .inode_alloc_security =         selinux_inode_alloc_security,
5469         .inode_free_security =          selinux_inode_free_security,
5470         .inode_init_security =          selinux_inode_init_security,
5471         .inode_create =                 selinux_inode_create,
5472         .inode_link =                   selinux_inode_link,
5473         .inode_unlink =                 selinux_inode_unlink,
5474         .inode_symlink =                selinux_inode_symlink,
5475         .inode_mkdir =                  selinux_inode_mkdir,
5476         .inode_rmdir =                  selinux_inode_rmdir,
5477         .inode_mknod =                  selinux_inode_mknod,
5478         .inode_rename =                 selinux_inode_rename,
5479         .inode_readlink =               selinux_inode_readlink,
5480         .inode_follow_link =            selinux_inode_follow_link,
5481         .inode_permission =             selinux_inode_permission,
5482         .inode_setattr =                selinux_inode_setattr,
5483         .inode_getattr =                selinux_inode_getattr,
5484         .inode_setxattr =               selinux_inode_setxattr,
5485         .inode_post_setxattr =          selinux_inode_post_setxattr,
5486         .inode_getxattr =               selinux_inode_getxattr,
5487         .inode_listxattr =              selinux_inode_listxattr,
5488         .inode_removexattr =            selinux_inode_removexattr,
5489         .inode_getsecurity =            selinux_inode_getsecurity,
5490         .inode_setsecurity =            selinux_inode_setsecurity,
5491         .inode_listsecurity =           selinux_inode_listsecurity,
5492         .inode_getsecid =               selinux_inode_getsecid,
5493
5494         .file_permission =              selinux_file_permission,
5495         .file_alloc_security =          selinux_file_alloc_security,
5496         .file_free_security =           selinux_file_free_security,
5497         .file_ioctl =                   selinux_file_ioctl,
5498         .file_mmap =                    selinux_file_mmap,
5499         .file_mprotect =                selinux_file_mprotect,
5500         .file_lock =                    selinux_file_lock,
5501         .file_fcntl =                   selinux_file_fcntl,
5502         .file_set_fowner =              selinux_file_set_fowner,
5503         .file_send_sigiotask =          selinux_file_send_sigiotask,
5504         .file_receive =                 selinux_file_receive,
5505
5506         .dentry_open =                  selinux_dentry_open,
5507
5508         .task_create =                  selinux_task_create,
5509         .cred_alloc_blank =             selinux_cred_alloc_blank,
5510         .cred_free =                    selinux_cred_free,
5511         .cred_prepare =                 selinux_cred_prepare,
5512         .cred_transfer =                selinux_cred_transfer,
5513         .kernel_act_as =                selinux_kernel_act_as,
5514         .kernel_create_files_as =       selinux_kernel_create_files_as,
5515         .kernel_module_request =        selinux_kernel_module_request,
5516         .task_setpgid =                 selinux_task_setpgid,
5517         .task_getpgid =                 selinux_task_getpgid,
5518         .task_getsid =                  selinux_task_getsid,
5519         .task_getsecid =                selinux_task_getsecid,
5520         .task_setnice =                 selinux_task_setnice,
5521         .task_setioprio =               selinux_task_setioprio,
5522         .task_getioprio =               selinux_task_getioprio,
5523         .task_setrlimit =               selinux_task_setrlimit,
5524         .task_setscheduler =            selinux_task_setscheduler,
5525         .task_getscheduler =            selinux_task_getscheduler,
5526         .task_movememory =              selinux_task_movememory,
5527         .task_kill =                    selinux_task_kill,
5528         .task_wait =                    selinux_task_wait,
5529         .task_to_inode =                selinux_task_to_inode,
5530
5531         .ipc_permission =               selinux_ipc_permission,
5532         .ipc_getsecid =                 selinux_ipc_getsecid,
5533
5534         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5535         .msg_msg_free_security =        selinux_msg_msg_free_security,
5536
5537         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5538         .msg_queue_free_security =      selinux_msg_queue_free_security,
5539         .msg_queue_associate =          selinux_msg_queue_associate,
5540         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5541         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5542         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5543
5544         .shm_alloc_security =           selinux_shm_alloc_security,
5545         .shm_free_security =            selinux_shm_free_security,
5546         .shm_associate =                selinux_shm_associate,
5547         .shm_shmctl =                   selinux_shm_shmctl,
5548         .shm_shmat =                    selinux_shm_shmat,
5549
5550         .sem_alloc_security =           selinux_sem_alloc_security,
5551         .sem_free_security =            selinux_sem_free_security,
5552         .sem_associate =                selinux_sem_associate,
5553         .sem_semctl =                   selinux_sem_semctl,
5554         .sem_semop =                    selinux_sem_semop,
5555
5556         .d_instantiate =                selinux_d_instantiate,
5557
5558         .getprocattr =                  selinux_getprocattr,
5559         .setprocattr =                  selinux_setprocattr,
5560
5561         .secid_to_secctx =              selinux_secid_to_secctx,
5562         .secctx_to_secid =              selinux_secctx_to_secid,
5563         .release_secctx =               selinux_release_secctx,
5564         .inode_notifysecctx =           selinux_inode_notifysecctx,
5565         .inode_setsecctx =              selinux_inode_setsecctx,
5566         .inode_getsecctx =              selinux_inode_getsecctx,
5567
5568         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5569         .unix_may_send =                selinux_socket_unix_may_send,
5570
5571         .socket_create =                selinux_socket_create,
5572         .socket_post_create =           selinux_socket_post_create,
5573         .socket_bind =                  selinux_socket_bind,
5574         .socket_connect =               selinux_socket_connect,
5575         .socket_listen =                selinux_socket_listen,
5576         .socket_accept =                selinux_socket_accept,
5577         .socket_sendmsg =               selinux_socket_sendmsg,
5578         .socket_recvmsg =               selinux_socket_recvmsg,
5579         .socket_getsockname =           selinux_socket_getsockname,
5580         .socket_getpeername =           selinux_socket_getpeername,
5581         .socket_getsockopt =            selinux_socket_getsockopt,
5582         .socket_setsockopt =            selinux_socket_setsockopt,
5583         .socket_shutdown =              selinux_socket_shutdown,
5584         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5585         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5586         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5587         .sk_alloc_security =            selinux_sk_alloc_security,
5588         .sk_free_security =             selinux_sk_free_security,
5589         .sk_clone_security =            selinux_sk_clone_security,
5590         .sk_getsecid =                  selinux_sk_getsecid,
5591         .sock_graft =                   selinux_sock_graft,
5592         .inet_conn_request =            selinux_inet_conn_request,
5593         .inet_csk_clone =               selinux_inet_csk_clone,
5594         .inet_conn_established =        selinux_inet_conn_established,
5595         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
5596         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
5597         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
5598         .req_classify_flow =            selinux_req_classify_flow,
5599         .tun_dev_create =               selinux_tun_dev_create,
5600         .tun_dev_post_create =          selinux_tun_dev_post_create,
5601         .tun_dev_attach =               selinux_tun_dev_attach,
5602
5603 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5604         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5605         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5606         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5607         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5608         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5609         .xfrm_state_free_security =     selinux_xfrm_state_free,
5610         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5611         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5612         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5613         .xfrm_decode_session =          selinux_xfrm_decode_session,
5614 #endif
5615
5616 #ifdef CONFIG_KEYS
5617         .key_alloc =                    selinux_key_alloc,
5618         .key_free =                     selinux_key_free,
5619         .key_permission =               selinux_key_permission,
5620         .key_getsecurity =              selinux_key_getsecurity,
5621 #endif
5622
5623 #ifdef CONFIG_AUDIT
5624         .audit_rule_init =              selinux_audit_rule_init,
5625         .audit_rule_known =             selinux_audit_rule_known,
5626         .audit_rule_match =             selinux_audit_rule_match,
5627         .audit_rule_free =              selinux_audit_rule_free,
5628 #endif
5629 };
5630
5631 static __init int selinux_init(void)
5632 {
5633         if (!security_module_enable(&selinux_ops)) {
5634                 selinux_enabled = 0;
5635                 return 0;
5636         }
5637
5638         if (!selinux_enabled) {
5639                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5640                 return 0;
5641         }
5642
5643         printk(KERN_INFO "SELinux:  Initializing.\n");
5644
5645         /* Set the security state for the initial task. */
5646         cred_init_security();
5647
5648         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5649
5650         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5651                                             sizeof(struct inode_security_struct),
5652                                             0, SLAB_PANIC, NULL);
5653         avc_init();
5654
5655         if (register_security(&selinux_ops))
5656                 panic("SELinux: Unable to register with kernel.\n");
5657
5658         if (selinux_enforcing)
5659                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5660         else
5661                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5662
5663         return 0;
5664 }
5665
5666 static void delayed_superblock_init(struct super_block *sb, void *unused)
5667 {
5668         superblock_doinit(sb, NULL);
5669 }
5670
5671 void selinux_complete_init(void)
5672 {
5673         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5674
5675         /* Set up any superblocks initialized prior to the policy load. */
5676         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5677         iterate_supers(delayed_superblock_init, NULL);
5678 }
5679
5680 /* SELinux requires early initialization in order to label
5681    all processes and objects when they are created. */
5682 security_initcall(selinux_init);
5683
5684 #if defined(CONFIG_NETFILTER)
5685
5686 static struct nf_hook_ops selinux_ipv4_ops[] = {
5687         {
5688                 .hook =         selinux_ipv4_postroute,
5689                 .owner =        THIS_MODULE,
5690                 .pf =           PF_INET,
5691                 .hooknum =      NF_INET_POST_ROUTING,
5692                 .priority =     NF_IP_PRI_SELINUX_LAST,
5693         },
5694         {
5695                 .hook =         selinux_ipv4_forward,
5696                 .owner =        THIS_MODULE,
5697                 .pf =           PF_INET,
5698                 .hooknum =      NF_INET_FORWARD,
5699                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5700         },
5701         {
5702                 .hook =         selinux_ipv4_output,
5703                 .owner =        THIS_MODULE,
5704                 .pf =           PF_INET,
5705                 .hooknum =      NF_INET_LOCAL_OUT,
5706                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5707         }
5708 };
5709
5710 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5711
5712 static struct nf_hook_ops selinux_ipv6_ops[] = {
5713         {
5714                 .hook =         selinux_ipv6_postroute,
5715                 .owner =        THIS_MODULE,
5716                 .pf =           PF_INET6,
5717                 .hooknum =      NF_INET_POST_ROUTING,
5718                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5719         },
5720         {
5721                 .hook =         selinux_ipv6_forward,
5722                 .owner =        THIS_MODULE,
5723                 .pf =           PF_INET6,
5724                 .hooknum =      NF_INET_FORWARD,
5725                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5726         }
5727 };
5728
5729 #endif  /* IPV6 */
5730
5731 static int __init selinux_nf_ip_init(void)
5732 {
5733         int err = 0;
5734
5735         if (!selinux_enabled)
5736                 goto out;
5737
5738         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5739
5740         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5741         if (err)
5742                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5743
5744 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5745         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5746         if (err)
5747                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5748 #endif  /* IPV6 */
5749
5750 out:
5751         return err;
5752 }
5753
5754 __initcall(selinux_nf_ip_init);
5755
5756 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5757 static void selinux_nf_ip_exit(void)
5758 {
5759         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5760
5761         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5762 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5763         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5764 #endif  /* IPV6 */
5765 }
5766 #endif
5767
5768 #else /* CONFIG_NETFILTER */
5769
5770 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5771 #define selinux_nf_ip_exit()
5772 #endif
5773
5774 #endif /* CONFIG_NETFILTER */
5775
5776 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5777 static int selinux_disabled;
5778
5779 int selinux_disable(void)
5780 {
5781         extern void exit_sel_fs(void);
5782
5783         if (ss_initialized) {
5784                 /* Not permitted after initial policy load. */
5785                 return -EINVAL;
5786         }
5787
5788         if (selinux_disabled) {
5789                 /* Only do this once. */
5790                 return -EINVAL;
5791         }
5792
5793         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5794
5795         selinux_disabled = 1;
5796         selinux_enabled = 0;
5797
5798         reset_security_ops();
5799
5800         /* Try to destroy the avc node cache */
5801         avc_disable();
5802
5803         /* Unregister netfilter hooks. */
5804         selinux_nf_ip_exit();
5805
5806         /* Unregister selinuxfs. */
5807         exit_sel_fs();
5808
5809         return 0;
5810 }
5811 #endif