security/selinux/hooks.c

   1 /*
   2  *  NSA Security-Enhanced Linux (SELinux) security module
   3  *
   4  *  This file contains the SELinux hook function implementations.
   5  *
   6  *  Authors:  Stephen Smalley, <[email protected]>
   7  *            Chris Vance, <[email protected]>
   8  *            Wayne Salamon, <[email protected]>
   9  *            James Morris <[email protected]>
  10  *
  11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <[email protected]>
  13  *                                         Eric Paris <[email protected]>
  14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  15  *                          <[email protected]>
  16  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
  17  *      Paul Moore <[email protected]>
  18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  19  *                     Yuichi Nakamura <[email protected]>
  20  *
  21  *      This program is free software; you can redistribute it and/or modify
  22  *      it under the terms of the GNU General Public License version 2,
  23  *      as published by the Free Software Foundation.
  24  */
  25
  26 #include <linux/init.h>
  27 #include <linux/kd.h>
  28 #include <linux/kernel.h>
  29 #include <linux/tracehook.h>
  30 #include <linux/errno.h>
  31 #include <linux/sched.h>
  32 #include <linux/security.h>
  33 #include <linux/xattr.h>
  34 #include <linux/capability.h>
  35 #include <linux/unistd.h>
  36 #include <linux/mm.h>
  37 #include <linux/mman.h>
  38 #include <linux/slab.h>
  39 #include <linux/pagemap.h>
  40 #include <linux/proc_fs.h>
  41 #include <linux/swap.h>
  42 #include <linux/spinlock.h>
  43 #include <linux/syscalls.h>
  44 #include <linux/dcache.h>
  45 #include <linux/file.h>
  46 #include <linux/fdtable.h>
  47 #include <linux/namei.h>
  48 #include <linux/mount.h>
  49 #include <linux/netfilter_ipv4.h>
  50 #include <linux/netfilter_ipv6.h>
  51 #include <linux/tty.h>
  52 #include <net/icmp.h>
  53 #include <net/ip.h>             /* for local_port_range[] */
  54 #include <net/sock.h>
  55 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  56 #include <net/inet_connection_sock.h>
  57 #include <net/net_namespace.h>
  58 #include <net/netlabel.h>
  59 #include <linux/uaccess.h>
  60 #include <asm/ioctls.h>
  61 #include <linux/atomic.h>
  62 #include <linux/bitops.h>
  63 #include <linux/interrupt.h>
  64 #include <linux/netdevice.h>    /* for network interface checks */
  65 #include <net/netlink.h>
  66 #include <linux/tcp.h>
  67 #include <linux/udp.h>
  68 #include <linux/dccp.h>
  69 #include <linux/quota.h>
  70 #include <linux/un.h>           /* for Unix socket types */
  71 #include <net/af_unix.h>        /* for Unix socket types */
  72 #include <linux/parser.h>
  73 #include <linux/nfs_mount.h>
  74 #include <net/ipv6.h>
  75 #include <linux/hugetlb.h>
  76 #include <linux/personality.h>
  77 #include <linux/audit.h>
  78 #include <linux/string.h>
  79 #include <linux/selinux.h>
  80 #include <linux/mutex.h>
  81 #include <linux/posix-timers.h>
  82 #include <linux/syslog.h>
  83 #include <linux/user_namespace.h>
  84 #include <linux/export.h>
  85 #include <linux/msg.h>
  86 #include <linux/shm.h>
  87
  88 #include "avc.h"
  89 #include "objsec.h"
  90 #include "netif.h"
  91 #include "netnode.h"
  92 #include "netport.h"
  93 #include "xfrm.h"
  94 #include "netlabel.h"
  95 #include "audit.h"
  96 #include "avc_ss.h"
  97
  98 extern struct security_operations *security_ops;
  99
 100 /* SECMARK reference count */
 101 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 102
 103 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 104 int selinux_enforcing;
 105
 106 static int __init enforcing_setup(char *str)
 107 {
 108         unsigned long enforcing;
 109         if (!strict_strtoul(str, 0, &enforcing))
 110                 selinux_enforcing = enforcing ? 1 : 0;
 111         return 1;
 112 }
 113 __setup("enforcing=", enforcing_setup);
 114 #endif
 115
 116 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 117 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
 118
 119 static int __init selinux_enabled_setup(char *str)
 120 {
 121         unsigned long enabled;
 122         if (!strict_strtoul(str, 0, &enabled))
 123                 selinux_enabled = enabled ? 1 : 0;
 124         return 1;
 125 }
 126 __setup("selinux=", selinux_enabled_setup);
 127 #else
 128 int selinux_enabled = 1;
 129 #endif
 130
 131 static struct kmem_cache *sel_inode_cache;
 132
 133 /**
 134  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 135  *
 136  * Description:
 137  * This function checks the SECMARK reference counter to see if any SECMARK
 138  * targets are currently configured, if the reference counter is greater than
 139  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 140  * enabled, false (0) if SECMARK is disabled.  If the always_check_network
 141  * policy capability is enabled, SECMARK is always considered enabled.
 142  *
 143  */
 144 static int selinux_secmark_enabled(void)
 145 {
 146         return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount));
 147 }
 148
 149 /**
 150  * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
 151  *
 152  * Description:
 153  * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
 154  * (1) if any are enabled or false (0) if neither are enabled.  If the
 155  * always_check_network policy capability is enabled, peer labeling
 156  * is always considered enabled.
 157  *
 158  */
 159 static int selinux_peerlbl_enabled(void)
 160 {
 161         return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled());
 162 }
 163
 164 /*
 165  * initialise the security for the init task
 166  */
 167 static void cred_init_security(void)
 168 {
 169         struct cred *cred = (struct cred *) current->real_cred;
 170         struct task_security_struct *tsec;
 171
 172         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 173         if (!tsec)
 174                 panic("SELinux:  Failed to initialize initial task.\n");
 175
 176         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 177         cred->security = tsec;
 178 }
 179
 180 /*
 181  * get the security ID of a set of credentials
 182  */
 183 static inline u32 cred_sid(const struct cred *cred)
 184 {
 185         const struct task_security_struct *tsec;
 186
 187         tsec = cred->security;
 188         return tsec->sid;
 189 }
 190
 191 /*
 192  * get the objective security ID of a task
 193  */
 194 static inline u32 task_sid(const struct task_struct *task)
 195 {
 196         u32 sid;
 197
 198         rcu_read_lock();
 199         sid = cred_sid(__task_cred(task));
 200         rcu_read_unlock();
 201         return sid;
 202 }
 203
 204 /*
 205  * get the subjective security ID of the current task
 206  */
 207 static inline u32 current_sid(void)
 208 {
 209         const struct task_security_struct *tsec = current_security();
 210
 211         return tsec->sid;
 212 }
 213
 214 /* Allocate and free functions for each kind of security blob. */
 215
 216 static int inode_alloc_security(struct inode *inode)
 217 {
 218         struct inode_security_struct *isec;
 219         u32 sid = current_sid();
 220
 221         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
 222         if (!isec)
 223                 return -ENOMEM;
 224
 225         mutex_init(&isec->lock);
 226         INIT_LIST_HEAD(&isec->list);
 227         isec->inode = inode;
 228         isec->sid = SECINITSID_UNLABELED;
 229         isec->sclass = SECCLASS_FILE;
 230         isec->task_sid = sid;
 231         inode->i_security = isec;
 232
 233         return 0;
 234 }
 235
 236 static void inode_free_rcu(struct rcu_head *head)
 237 {
 238         struct inode_security_struct *isec;
 239
 240         isec = container_of(head, struct inode_security_struct, rcu);
 241         kmem_cache_free(sel_inode_cache, isec);
 242 }
 243
 244 static void inode_free_security(struct inode *inode)
 245 {
 246         struct inode_security_struct *isec = inode->i_security;
 247         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 248
 249         spin_lock(&sbsec->isec_lock);
 250         if (!list_empty(&isec->list))
 251                 list_del_init(&isec->list);
 252         spin_unlock(&sbsec->isec_lock);
 253
 254         /*
 255          * The inode may still be referenced in a path walk and
 256          * a call to selinux_inode_permission() can be made
 257          * after inode_free_security() is called. Ideally, the VFS
 258          * wouldn't do this, but fixing that is a much harder
 259          * job. For now, simply free the i_security via RCU, and
 260          * leave the current inode->i_security pointer intact.
 261          * The inode will be freed after the RCU grace period too.
 262          */
 263         call_rcu(&isec->rcu, inode_free_rcu);
 264 }
 265
 266 static int file_alloc_security(struct file *file)
 267 {
 268         struct file_security_struct *fsec;
 269         u32 sid = current_sid();
 270
 271         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
 272         if (!fsec)
 273                 return -ENOMEM;
 274
 275         fsec->sid = sid;
 276         fsec->fown_sid = sid;
 277         file->f_security = fsec;
 278
 279         return 0;
 280 }
 281
 282 static void file_free_security(struct file *file)
 283 {
 284         struct file_security_struct *fsec = file->f_security;
 285         file->f_security = NULL;
 286         kfree(fsec);
 287 }
 288
 289 static int superblock_alloc_security(struct super_block *sb)
 290 {
 291         struct superblock_security_struct *sbsec;
 292
 293         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 294         if (!sbsec)
 295                 return -ENOMEM;
 296
 297         mutex_init(&sbsec->lock);
 298         INIT_LIST_HEAD(&sbsec->isec_head);
 299         spin_lock_init(&sbsec->isec_lock);
 300         sbsec->sb = sb;
 301         sbsec->sid = SECINITSID_UNLABELED;
 302         sbsec->def_sid = SECINITSID_FILE;
 303         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 304         sb->s_security = sbsec;
 305
 306         return 0;
 307 }
 308
 309 static void superblock_free_security(struct super_block *sb)
 310 {
 311         struct superblock_security_struct *sbsec = sb->s_security;
 312         sb->s_security = NULL;
 313         kfree(sbsec);
 314 }
 315
 316 /* The file system's label must be initialized prior to use. */
 317
 318 static const char *labeling_behaviors[7] = {
 319         "uses xattr",
 320         "uses transition SIDs",
 321         "uses task SIDs",
 322         "uses genfs_contexts",
 323         "not configured for labeling",
 324         "uses mountpoint labeling",
 325         "uses native labeling",
 326 };
 327
 328 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 329
 330 static inline int inode_doinit(struct inode *inode)
 331 {
 332         return inode_doinit_with_dentry(inode, NULL);
 333 }
 334
 335 enum {
 336         Opt_error = -1,
 337         Opt_context = 1,
 338         Opt_fscontext = 2,
 339         Opt_defcontext = 3,
 340         Opt_rootcontext = 4,
 341         Opt_labelsupport = 5,
 342         Opt_nextmntopt = 6,
 343 };
 344
 345 #define NUM_SEL_MNT_OPTS        (Opt_nextmntopt - 1)
 346
 347 static const match_table_t tokens = {
 348         {Opt_context, CONTEXT_STR "%s"},
 349         {Opt_fscontext, FSCONTEXT_STR "%s"},
 350         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 351         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 352         {Opt_labelsupport, LABELSUPP_STR},
 353         {Opt_error, NULL},
 354 };
 355
 356 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 357
 358 static int may_context_mount_sb_relabel(u32 sid,
 359                         struct superblock_security_struct *sbsec,
 360                         const struct cred *cred)
 361 {
 362         const struct task_security_struct *tsec = cred->security;
 363         int rc;
 364
 365         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 366                           FILESYSTEM__RELABELFROM, NULL);
 367         if (rc)
 368                 return rc;
 369
 370         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 371                           FILESYSTEM__RELABELTO, NULL);
 372         return rc;
 373 }
 374
 375 static int may_context_mount_inode_relabel(u32 sid,
 376                         struct superblock_security_struct *sbsec,
 377                         const struct cred *cred)
 378 {
 379         const struct task_security_struct *tsec = cred->security;
 380         int rc;
 381         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 382                           FILESYSTEM__RELABELFROM, NULL);
 383         if (rc)
 384                 return rc;
 385
 386         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 387                           FILESYSTEM__ASSOCIATE, NULL);
 388         return rc;
 389 }
 390
 391 static int selinux_is_sblabel_mnt(struct super_block *sb)
 392 {
 393         struct superblock_security_struct *sbsec = sb->s_security;
 394
 395         if (sbsec->behavior == SECURITY_FS_USE_XATTR ||
 396             sbsec->behavior == SECURITY_FS_USE_TRANS ||
 397             sbsec->behavior == SECURITY_FS_USE_TASK)
 398                 return 1;
 399
 400         /* Special handling for sysfs. Is genfs but also has setxattr handler*/
 401         if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
 402                 return 1;
 403
 404         /*
 405          * Special handling for rootfs. Is genfs but supports
 406          * setting SELinux context on in-core inodes.
 407          */
 408         if (strncmp(sb->s_type->name, "rootfs", sizeof("rootfs")) == 0)
 409                 return 1;
 410
 411         return 0;
 412 }
 413
 414 static int sb_finish_set_opts(struct super_block *sb)
 415 {
 416         struct superblock_security_struct *sbsec = sb->s_security;
 417         struct dentry *root = sb->s_root;
 418         struct inode *root_inode = root->d_inode;
 419         int rc = 0;
 420
 421         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 422                 /* Make sure that the xattr handler exists and that no
 423                    error other than -ENODATA is returned by getxattr on
 424                    the root directory.  -ENODATA is ok, as this may be
 425                    the first boot of the SELinux kernel before we have
 426                    assigned xattr values to the filesystem. */
 427                 if (!root_inode->i_op->getxattr) {
 428                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
 429                                "xattr support\n", sb->s_id, sb->s_type->name);
 430                         rc = -EOPNOTSUPP;
 431                         goto out;
 432                 }
 433                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
 434                 if (rc < 0 && rc != -ENODATA) {
 435                         if (rc == -EOPNOTSUPP)
 436                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 437                                        "%s) has no security xattr handler\n",
 438                                        sb->s_id, sb->s_type->name);
 439                         else
 440                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 441                                        "%s) getxattr errno %d\n", sb->s_id,
 442                                        sb->s_type->name, -rc);
 443                         goto out;
 444                 }
 445         }
 446
 447         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 448                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
 449                        sb->s_id, sb->s_type->name);
 450         else
 451                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
 452                        sb->s_id, sb->s_type->name,
 453                        labeling_behaviors[sbsec->behavior-1]);
 454
 455         sbsec->flags |= SE_SBINITIALIZED;
 456         if (selinux_is_sblabel_mnt(sb))
 457                 sbsec->flags |= SBLABEL_MNT;
 458
 459         /* Initialize the root inode. */
 460         rc = inode_doinit_with_dentry(root_inode, root);
 461
 462         /* Initialize any other inodes associated with the superblock, e.g.
 463            inodes created prior to initial policy load or inodes created
 464            during get_sb by a pseudo filesystem that directly
 465            populates itself. */
 466         spin_lock(&sbsec->isec_lock);
 467 next_inode:
 468         if (!list_empty(&sbsec->isec_head)) {
 469                 struct inode_security_struct *isec =
 470                                 list_entry(sbsec->isec_head.next,
 471                                            struct inode_security_struct, list);
 472                 struct inode *inode = isec->inode;
 473                 spin_unlock(&sbsec->isec_lock);
 474                 inode = igrab(inode);
 475                 if (inode) {
 476                         if (!IS_PRIVATE(inode))
 477                                 inode_doinit(inode);
 478                         iput(inode);
 479                 }
 480                 spin_lock(&sbsec->isec_lock);
 481                 list_del_init(&isec->list);
 482                 goto next_inode;
 483         }
 484         spin_unlock(&sbsec->isec_lock);
 485 out:
 486         return rc;
 487 }
 488
 489 /*
 490  * This function should allow an FS to ask what it's mount security
 491  * options were so it can use those later for submounts, displaying
 492  * mount options, or whatever.
 493  */
 494 static int selinux_get_mnt_opts(const struct super_block *sb,
 495                                 struct security_mnt_opts *opts)
 496 {
 497         int rc = 0, i;
 498         struct superblock_security_struct *sbsec = sb->s_security;
 499         char *context = NULL;
 500         u32 len;
 501         char tmp;
 502
 503         security_init_mnt_opts(opts);
 504
 505         if (!(sbsec->flags & SE_SBINITIALIZED))
 506                 return -EINVAL;
 507
 508         if (!ss_initialized)
 509                 return -EINVAL;
 510
 511         /* make sure we always check enough bits to cover the mask */
 512         BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));
 513
 514         tmp = sbsec->flags & SE_MNTMASK;
 515         /* count the number of mount options for this sb */
 516         for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
 517                 if (tmp & 0x01)
 518                         opts->num_mnt_opts++;
 519                 tmp >>= 1;
 520         }
 521         /* Check if the Label support flag is set */
 522         if (sbsec->flags & SBLABEL_MNT)
 523                 opts->num_mnt_opts++;
 524
 525         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 526         if (!opts->mnt_opts) {
 527                 rc = -ENOMEM;
 528                 goto out_free;
 529         }
 530
 531         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 532         if (!opts->mnt_opts_flags) {
 533                 rc = -ENOMEM;
 534                 goto out_free;
 535         }
 536
 537         i = 0;
 538         if (sbsec->flags & FSCONTEXT_MNT) {
 539                 rc = security_sid_to_context(sbsec->sid, &context, &len);
 540                 if (rc)
 541                         goto out_free;
 542                 opts->mnt_opts[i] = context;
 543                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 544         }
 545         if (sbsec->flags & CONTEXT_MNT) {
 546                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
 547                 if (rc)
 548                         goto out_free;
 549                 opts->mnt_opts[i] = context;
 550                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 551         }
 552         if (sbsec->flags & DEFCONTEXT_MNT) {
 553                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
 554                 if (rc)
 555                         goto out_free;
 556                 opts->mnt_opts[i] = context;
 557                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 558         }
 559         if (sbsec->flags & ROOTCONTEXT_MNT) {
 560                 struct inode *root = sbsec->sb->s_root->d_inode;
 561                 struct inode_security_struct *isec = root->i_security;
 562
 563                 rc = security_sid_to_context(isec->sid, &context, &len);
 564                 if (rc)
 565                         goto out_free;
 566                 opts->mnt_opts[i] = context;
 567                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 568         }
 569         if (sbsec->flags & SBLABEL_MNT) {
 570                 opts->mnt_opts[i] = NULL;
 571                 opts->mnt_opts_flags[i++] = SBLABEL_MNT;
 572         }
 573
 574         BUG_ON(i != opts->num_mnt_opts);
 575
 576         return 0;
 577
 578 out_free:
 579         security_free_mnt_opts(opts);
 580         return rc;
 581 }
 582
 583 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 584                       u32 old_sid, u32 new_sid)
 585 {
 586         char mnt_flags = sbsec->flags & SE_MNTMASK;
 587
 588         /* check if the old mount command had the same options */
 589         if (sbsec->flags & SE_SBINITIALIZED)
 590                 if (!(sbsec->flags & flag) ||
 591                     (old_sid != new_sid))
 592                         return 1;
 593
 594         /* check if we were passed the same options twice,
 595          * aka someone passed context=a,context=b
 596          */
 597         if (!(sbsec->flags & SE_SBINITIALIZED))
 598                 if (mnt_flags & flag)
 599                         return 1;
 600         return 0;
 601 }
 602
 603 /*
 604  * Allow filesystems with binary mount data to explicitly set mount point
 605  * labeling information.
 606  */
 607 static int selinux_set_mnt_opts(struct super_block *sb,
 608                                 struct security_mnt_opts *opts,
 609                                 unsigned long kern_flags,
 610                                 unsigned long *set_kern_flags)
 611 {
 612         const struct cred *cred = current_cred();
 613         int rc = 0, i;
 614         struct superblock_security_struct *sbsec = sb->s_security;
 615         const char *name = sb->s_type->name;
 616         struct inode *inode = sbsec->sb->s_root->d_inode;
 617         struct inode_security_struct *root_isec = inode->i_security;
 618         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 619         u32 defcontext_sid = 0;
 620         char **mount_options = opts->mnt_opts;
 621         int *flags = opts->mnt_opts_flags;
 622         int num_opts = opts->num_mnt_opts;
 623
 624         mutex_lock(&sbsec->lock);
 625
 626         if (!ss_initialized) {
 627                 if (!num_opts) {
 628                         /* Defer initialization until selinux_complete_init,
 629                            after the initial policy is loaded and the security
 630                            server is ready to handle calls. */
 631                         goto out;
 632                 }
 633                 rc = -EINVAL;
 634                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
 635                         "before the security server is initialized\n");
 636                 goto out;
 637         }
 638         if (kern_flags && !set_kern_flags) {
 639                 /* Specifying internal flags without providing a place to
 640                  * place the results is not allowed */
 641                 rc = -EINVAL;
 642                 goto out;
 643         }
 644
 645         /*
 646          * Binary mount data FS will come through this function twice.  Once
 647          * from an explicit call and once from the generic calls from the vfs.
 648          * Since the generic VFS calls will not contain any security mount data
 649          * we need to skip the double mount verification.
 650          *
 651          * This does open a hole in which we will not notice if the first
 652          * mount using this sb set explict options and a second mount using
 653          * this sb does not set any security options.  (The first options
 654          * will be used for both mounts)
 655          */
 656         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 657             && (num_opts == 0))
 658                 goto out;
 659
 660         /*
 661          * parse the mount options, check if they are valid sids.
 662          * also check if someone is trying to mount the same sb more
 663          * than once with different security options.
 664          */
 665         for (i = 0; i < num_opts; i++) {
 666                 u32 sid;
 667
 668                 if (flags[i] == SBLABEL_MNT)
 669                         continue;
 670                 rc = security_context_to_sid(mount_options[i],
 671                                              strlen(mount_options[i]), &sid, GFP_KERNEL);
 672                 if (rc) {
 673                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 674                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 675                                mount_options[i], sb->s_id, name, rc);
 676                         goto out;
 677                 }
 678                 switch (flags[i]) {
 679                 case FSCONTEXT_MNT:
 680                         fscontext_sid = sid;
 681
 682                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 683                                         fscontext_sid))
 684                                 goto out_double_mount;
 685
 686                         sbsec->flags |= FSCONTEXT_MNT;
 687                         break;
 688                 case CONTEXT_MNT:
 689                         context_sid = sid;
 690
 691                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 692                                         context_sid))
 693                                 goto out_double_mount;
 694
 695                         sbsec->flags |= CONTEXT_MNT;
 696                         break;
 697                 case ROOTCONTEXT_MNT:
 698                         rootcontext_sid = sid;
 699
 700                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 701                                         rootcontext_sid))
 702                                 goto out_double_mount;
 703
 704                         sbsec->flags |= ROOTCONTEXT_MNT;
 705
 706                         break;
 707                 case DEFCONTEXT_MNT:
 708                         defcontext_sid = sid;
 709
 710                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 711                                         defcontext_sid))
 712                                 goto out_double_mount;
 713
 714                         sbsec->flags |= DEFCONTEXT_MNT;
 715
 716                         break;
 717                 default:
 718                         rc = -EINVAL;
 719                         goto out;
 720                 }
 721         }
 722
 723         if (sbsec->flags & SE_SBINITIALIZED) {
 724                 /* previously mounted with options, but not on this attempt? */
 725                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
 726                         goto out_double_mount;
 727                 rc = 0;
 728                 goto out;
 729         }
 730
 731         if (strcmp(sb->s_type->name, "proc") == 0)
 732                 sbsec->flags |= SE_SBPROC;
 733
 734         if (!sbsec->behavior) {
 735                 /*
 736                  * Determine the labeling behavior to use for this
 737                  * filesystem type.
 738                  */
 739                 rc = security_fs_use(sb);
 740                 if (rc) {
 741                         printk(KERN_WARNING
 742                                 "%s: security_fs_use(%s) returned %d\n",
 743                                         __func__, sb->s_type->name, rc);
 744                         goto out;
 745                 }
 746         }
 747         /* sets the context of the superblock for the fs being mounted. */
 748         if (fscontext_sid) {
 749                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 750                 if (rc)
 751                         goto out;
 752
 753                 sbsec->sid = fscontext_sid;
 754         }
 755
 756         /*
 757          * Switch to using mount point labeling behavior.
 758          * sets the label used on all file below the mountpoint, and will set
 759          * the superblock context if not already set.
 760          */
 761         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
 762                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 763                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 764         }
 765
 766         if (context_sid) {
 767                 if (!fscontext_sid) {
 768                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 769                                                           cred);
 770                         if (rc)
 771                                 goto out;
 772                         sbsec->sid = context_sid;
 773                 } else {
 774                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 775                                                              cred);
 776                         if (rc)
 777                                 goto out;
 778                 }
 779                 if (!rootcontext_sid)
 780                         rootcontext_sid = context_sid;
 781
 782                 sbsec->mntpoint_sid = context_sid;
 783                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 784         }
 785
 786         if (rootcontext_sid) {
 787                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 788                                                      cred);
 789                 if (rc)
 790                         goto out;
 791
 792                 root_isec->sid = rootcontext_sid;
 793                 root_isec->initialized = 1;
 794         }
 795
 796         if (defcontext_sid) {
 797                 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
 798                         sbsec->behavior != SECURITY_FS_USE_NATIVE) {
 799                         rc = -EINVAL;
 800                         printk(KERN_WARNING "SELinux: defcontext option is "
 801                                "invalid for this filesystem type\n");
 802                         goto out;
 803                 }
 804
 805                 if (defcontext_sid != sbsec->def_sid) {
 806                         rc = may_context_mount_inode_relabel(defcontext_sid,
 807                                                              sbsec, cred);
 808                         if (rc)
 809                                 goto out;
 810                 }
 811
 812                 sbsec->def_sid = defcontext_sid;
 813         }
 814
 815         rc = sb_finish_set_opts(sb);
 816 out:
 817         mutex_unlock(&sbsec->lock);
 818         return rc;
 819 out_double_mount:
 820         rc = -EINVAL;
 821         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 822                "security settings for (dev %s, type %s)\n", sb->s_id, name);
 823         goto out;
 824 }
 825
 826 static int selinux_cmp_sb_context(const struct super_block *oldsb,
 827                                     const struct super_block *newsb)
 828 {
 829         struct superblock_security_struct *old = oldsb->s_security;
 830         struct superblock_security_struct *new = newsb->s_security;
 831         char oldflags = old->flags & SE_MNTMASK;
 832         char newflags = new->flags & SE_MNTMASK;
 833
 834         if (oldflags != newflags)
 835                 goto mismatch;
 836         if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
 837                 goto mismatch;
 838         if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
 839                 goto mismatch;
 840         if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
 841                 goto mismatch;
 842         if (oldflags & ROOTCONTEXT_MNT) {
 843                 struct inode_security_struct *oldroot = oldsb->s_root->d_inode->i_security;
 844                 struct inode_security_struct *newroot = newsb->s_root->d_inode->i_security;
 845                 if (oldroot->sid != newroot->sid)
 846                         goto mismatch;
 847         }
 848         return 0;
 849 mismatch:
 850         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, "
 851                             "different security settings for (dev %s, "
 852                             "type %s)\n", newsb->s_id, newsb->s_type->name);
 853         return -EBUSY;
 854 }
 855
 856 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 857                                         struct super_block *newsb)
 858 {
 859         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 860         struct superblock_security_struct *newsbsec = newsb->s_security;
 861
 862         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 863         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 864         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 865
 866         /*
 867          * if the parent was able to be mounted it clearly had no special lsm
 868          * mount options.  thus we can safely deal with this superblock later
 869          */
 870         if (!ss_initialized)
 871                 return 0;
 872
 873         /* how can we clone if the old one wasn't set up?? */
 874         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 875
 876         /* if fs is reusing a sb, make sure that the contexts match */
 877         if (newsbsec->flags & SE_SBINITIALIZED)
 878                 return selinux_cmp_sb_context(oldsb, newsb);
 879
 880         mutex_lock(&newsbsec->lock);
 881
 882         newsbsec->flags = oldsbsec->flags;
 883
 884         newsbsec->sid = oldsbsec->sid;
 885         newsbsec->def_sid = oldsbsec->def_sid;
 886         newsbsec->behavior = oldsbsec->behavior;
 887
 888         if (set_context) {
 889                 u32 sid = oldsbsec->mntpoint_sid;
 890
 891                 if (!set_fscontext)
 892                         newsbsec->sid = sid;
 893                 if (!set_rootcontext) {
 894                         struct inode *newinode = newsb->s_root->d_inode;
 895                         struct inode_security_struct *newisec = newinode->i_security;
 896                         newisec->sid = sid;
 897                 }
 898                 newsbsec->mntpoint_sid = sid;
 899         }
 900         if (set_rootcontext) {
 901                 const struct inode *oldinode = oldsb->s_root->d_inode;
 902                 const struct inode_security_struct *oldisec = oldinode->i_security;
 903                 struct inode *newinode = newsb->s_root->d_inode;
 904                 struct inode_security_struct *newisec = newinode->i_security;
 905
 906                 newisec->sid = oldisec->sid;
 907         }
 908
 909         sb_finish_set_opts(newsb);
 910         mutex_unlock(&newsbsec->lock);
 911         return 0;
 912 }
 913
 914 static int selinux_parse_opts_str(char *options,
 915                                   struct security_mnt_opts *opts)
 916 {
 917         char *p;
 918         char *context = NULL, *defcontext = NULL;
 919         char *fscontext = NULL, *rootcontext = NULL;
 920         int rc, num_mnt_opts = 0;
 921
 922         opts->num_mnt_opts = 0;
 923
 924         /* Standard string-based options. */
 925         while ((p = strsep(&options, "|")) != NULL) {
 926                 int token;
 927                 substring_t args[MAX_OPT_ARGS];
 928
 929                 if (!*p)
 930                         continue;
 931
 932                 token = match_token(p, tokens, args);
 933
 934                 switch (token) {
 935                 case Opt_context:
 936                         if (context || defcontext) {
 937                                 rc = -EINVAL;
 938                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 939                                 goto out_err;
 940                         }
 941                         context = match_strdup(&args[0]);
 942                         if (!context) {
 943                                 rc = -ENOMEM;
 944                                 goto out_err;
 945                         }
 946                         break;
 947
 948                 case Opt_fscontext:
 949                         if (fscontext) {
 950                                 rc = -EINVAL;
 951                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 952                                 goto out_err;
 953                         }
 954                         fscontext = match_strdup(&args[0]);
 955                         if (!fscontext) {
 956                                 rc = -ENOMEM;
 957                                 goto out_err;
 958                         }
 959                         break;
 960
 961                 case Opt_rootcontext:
 962                         if (rootcontext) {
 963                                 rc = -EINVAL;
 964                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 965                                 goto out_err;
 966                         }
 967                         rootcontext = match_strdup(&args[0]);
 968                         if (!rootcontext) {
 969                                 rc = -ENOMEM;
 970                                 goto out_err;
 971                         }
 972                         break;
 973
 974                 case Opt_defcontext:
 975                         if (context || defcontext) {
 976                                 rc = -EINVAL;
 977                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 978                                 goto out_err;
 979                         }
 980                         defcontext = match_strdup(&args[0]);
 981                         if (!defcontext) {
 982                                 rc = -ENOMEM;
 983                                 goto out_err;
 984                         }
 985                         break;
 986                 case Opt_labelsupport:
 987                         break;
 988                 default:
 989                         rc = -EINVAL;
 990                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
 991                         goto out_err;
 992
 993                 }
 994         }
 995
 996         rc = -ENOMEM;
 997         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
 998         if (!opts->mnt_opts)
 999                 goto out_err;
1000
1001         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
1002         if (!opts->mnt_opts_flags) {
1003                 kfree(opts->mnt_opts);
1004                 goto out_err;
1005         }
1006
1007         if (fscontext) {
1008                 opts->mnt_opts[num_mnt_opts] = fscontext;
1009                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1010         }
1011         if (context) {
1012                 opts->mnt_opts[num_mnt_opts] = context;
1013                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1014         }
1015         if (rootcontext) {
1016                 opts->mnt_opts[num_mnt_opts] = rootcontext;
1017                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1018         }
1019         if (defcontext) {
1020                 opts->mnt_opts[num_mnt_opts] = defcontext;
1021                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1022         }
1023
1024         opts->num_mnt_opts = num_mnt_opts;
1025         return 0;
1026
1027 out_err:
1028         kfree(context);
1029         kfree(defcontext);
1030         kfree(fscontext);
1031         kfree(rootcontext);
1032         return rc;
1033 }
1034 /*
1035  * string mount options parsing and call set the sbsec
1036  */
1037 static int superblock_doinit(struct super_block *sb, void *data)
1038 {
1039         int rc = 0;
1040         char *options = data;
1041         struct security_mnt_opts opts;
1042
1043         security_init_mnt_opts(&opts);
1044
1045         if (!data)
1046                 goto out;
1047
1048         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
1049
1050         rc = selinux_parse_opts_str(options, &opts);
1051         if (rc)
1052                 goto out_err;
1053
1054 out:
1055         rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1056
1057 out_err:
1058         security_free_mnt_opts(&opts);
1059         return rc;
1060 }
1061
1062 static void selinux_write_opts(struct seq_file *m,
1063                                struct security_mnt_opts *opts)
1064 {
1065         int i;
1066         char *prefix;
1067
1068         for (i = 0; i < opts->num_mnt_opts; i++) {
1069                 char *has_comma;
1070
1071                 if (opts->mnt_opts[i])
1072                         has_comma = strchr(opts->mnt_opts[i], ',');
1073                 else
1074                         has_comma = NULL;
1075
1076                 switch (opts->mnt_opts_flags[i]) {
1077                 case CONTEXT_MNT:
1078                         prefix = CONTEXT_STR;
1079                         break;
1080                 case FSCONTEXT_MNT:
1081                         prefix = FSCONTEXT_STR;
1082                         break;
1083                 case ROOTCONTEXT_MNT:
1084                         prefix = ROOTCONTEXT_STR;
1085                         break;
1086                 case DEFCONTEXT_MNT:
1087                         prefix = DEFCONTEXT_STR;
1088                         break;
1089                 case SBLABEL_MNT:
1090                         seq_putc(m, ',');
1091                         seq_puts(m, LABELSUPP_STR);
1092                         continue;
1093                 default:
1094                         BUG();
1095                         return;
1096                 };
1097                 /* we need a comma before each option */
1098                 seq_putc(m, ',');
1099                 seq_puts(m, prefix);
1100                 if (has_comma)
1101                         seq_putc(m, '\"');
1102                 seq_puts(m, opts->mnt_opts[i]);
1103                 if (has_comma)
1104                         seq_putc(m, '\"');
1105         }
1106 }
1107
1108 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1109 {
1110         struct security_mnt_opts opts;
1111         int rc;
1112
1113         rc = selinux_get_mnt_opts(sb, &opts);
1114         if (rc) {
1115                 /* before policy load we may get EINVAL, don't show anything */
1116                 if (rc == -EINVAL)
1117                         rc = 0;
1118                 return rc;
1119         }
1120
1121         selinux_write_opts(m, &opts);
1122
1123         security_free_mnt_opts(&opts);
1124
1125         return rc;
1126 }
1127
1128 static inline u16 inode_mode_to_security_class(umode_t mode)
1129 {
1130         switch (mode & S_IFMT) {
1131         case S_IFSOCK:
1132                 return SECCLASS_SOCK_FILE;
1133         case S_IFLNK:
1134                 return SECCLASS_LNK_FILE;
1135         case S_IFREG:
1136                 return SECCLASS_FILE;
1137         case S_IFBLK:
1138                 return SECCLASS_BLK_FILE;
1139         case S_IFDIR:
1140                 return SECCLASS_DIR;
1141         case S_IFCHR:
1142                 return SECCLASS_CHR_FILE;
1143         case S_IFIFO:
1144                 return SECCLASS_FIFO_FILE;
1145
1146         }
1147
1148         return SECCLASS_FILE;
1149 }
1150
1151 static inline int default_protocol_stream(int protocol)
1152 {
1153         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1154 }
1155
1156 static inline int default_protocol_dgram(int protocol)
1157 {
1158         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1159 }
1160
1161 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1162 {
1163         switch (family) {
1164         case PF_UNIX:
1165                 switch (type) {
1166                 case SOCK_STREAM:
1167                 case SOCK_SEQPACKET:
1168                         return SECCLASS_UNIX_STREAM_SOCKET;
1169                 case SOCK_DGRAM:
1170                         return SECCLASS_UNIX_DGRAM_SOCKET;
1171                 }
1172                 break;
1173         case PF_INET:
1174         case PF_INET6:
1175                 switch (type) {
1176                 case SOCK_STREAM:
1177                         if (default_protocol_stream(protocol))
1178                                 return SECCLASS_TCP_SOCKET;
1179                         else
1180                                 return SECCLASS_RAWIP_SOCKET;
1181                 case SOCK_DGRAM:
1182                         if (default_protocol_dgram(protocol))
1183                                 return SECCLASS_UDP_SOCKET;
1184                         else
1185                                 return SECCLASS_RAWIP_SOCKET;
1186                 case SOCK_DCCP:
1187                         return SECCLASS_DCCP_SOCKET;
1188                 default:
1189                         return SECCLASS_RAWIP_SOCKET;
1190                 }
1191                 break;
1192         case PF_NETLINK:
1193                 switch (protocol) {
1194                 case NETLINK_ROUTE:
1195                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1196                 case NETLINK_FIREWALL:
1197                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1198                 case NETLINK_SOCK_DIAG:
1199                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1200                 case NETLINK_NFLOG:
1201                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1202                 case NETLINK_XFRM:
1203                         return SECCLASS_NETLINK_XFRM_SOCKET;
1204                 case NETLINK_SELINUX:
1205                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1206                 case NETLINK_AUDIT:
1207                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1208                 case NETLINK_IP6_FW:
1209                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1210                 case NETLINK_DNRTMSG:
1211                         return SECCLASS_NETLINK_DNRT_SOCKET;
1212                 case NETLINK_KOBJECT_UEVENT:
1213                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1214                 default:
1215                         return SECCLASS_NETLINK_SOCKET;
1216                 }
1217         case PF_PACKET:
1218                 return SECCLASS_PACKET_SOCKET;
1219         case PF_KEY:
1220                 return SECCLASS_KEY_SOCKET;
1221         case PF_APPLETALK:
1222                 return SECCLASS_APPLETALK_SOCKET;
1223         }
1224
1225         return SECCLASS_SOCKET;
1226 }
1227
1228 #ifdef CONFIG_PROC_FS
1229 static int selinux_proc_get_sid(struct dentry *dentry,
1230                                 u16 tclass,
1231                                 u32 *sid)
1232 {
1233         int rc;
1234         char *buffer, *path;
1235
1236         buffer = (char *)__get_free_page(GFP_KERNEL);
1237         if (!buffer)
1238                 return -ENOMEM;
1239
1240         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1241         if (IS_ERR(path))
1242                 rc = PTR_ERR(path);
1243         else {
1244                 /* each process gets a /proc/PID/ entry. Strip off the
1245                  * PID part to get a valid selinux labeling.
1246                  * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1247                 while (path[1] >= '0' && path[1] <= '9') {
1248                         path[1] = '/';
1249                         path++;
1250                 }
1251                 rc = security_genfs_sid("proc", path, tclass, sid);
1252         }
1253         free_page((unsigned long)buffer);
1254         return rc;
1255 }
1256 #else
1257 static int selinux_proc_get_sid(struct dentry *dentry,
1258                                 u16 tclass,
1259                                 u32 *sid)
1260 {
1261         return -EINVAL;
1262 }
1263 #endif
1264
1265 /* The inode's security attributes must be initialized before first use. */
1266 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1267 {
1268         struct superblock_security_struct *sbsec = NULL;
1269         struct inode_security_struct *isec = inode->i_security;
1270         u32 sid;
1271         struct dentry *dentry;
1272 #define INITCONTEXTLEN 255
1273         char *context = NULL;
1274         unsigned len = 0;
1275         int rc = 0;
1276
1277         if (isec->initialized)
1278                 goto out;
1279
1280         mutex_lock(&isec->lock);
1281         if (isec->initialized)
1282                 goto out_unlock;
1283
1284         sbsec = inode->i_sb->s_security;
1285         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1286                 /* Defer initialization until selinux_complete_init,
1287                    after the initial policy is loaded and the security
1288                    server is ready to handle calls. */
1289                 spin_lock(&sbsec->isec_lock);
1290                 if (list_empty(&isec->list))
1291                         list_add(&isec->list, &sbsec->isec_head);
1292                 spin_unlock(&sbsec->isec_lock);
1293                 goto out_unlock;
1294         }
1295
1296         switch (sbsec->behavior) {
1297         case SECURITY_FS_USE_NATIVE:
1298                 break;
1299         case SECURITY_FS_USE_XATTR:
1300                 if (!inode->i_op->getxattr) {
1301                         isec->sid = sbsec->def_sid;
1302                         break;
1303                 }
1304
1305                 /* Need a dentry, since the xattr API requires one.
1306                    Life would be simpler if we could just pass the inode. */
1307                 if (opt_dentry) {
1308                         /* Called from d_instantiate or d_splice_alias. */
1309                         dentry = dget(opt_dentry);
1310                 } else {
1311                         /* Called from selinux_complete_init, try to find a dentry. */
1312                         dentry = d_find_alias(inode);
1313                 }
1314                 if (!dentry) {
1315                         /*
1316                          * this is can be hit on boot when a file is accessed
1317                          * before the policy is loaded.  When we load policy we
1318                          * may find inodes that have no dentry on the
1319                          * sbsec->isec_head list.  No reason to complain as these
1320                          * will get fixed up the next time we go through
1321                          * inode_doinit with a dentry, before these inodes could
1322                          * be used again by userspace.
1323                          */
1324                         goto out_unlock;
1325                 }
1326
1327                 len = INITCONTEXTLEN;
1328                 context = kmalloc(len+1, GFP_NOFS);
1329                 if (!context) {
1330                         rc = -ENOMEM;
1331                         dput(dentry);
1332                         goto out_unlock;
1333                 }
1334                 context[len] = '\0';
1335                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1336                                            context, len);
1337                 if (rc == -ERANGE) {
1338                         kfree(context);
1339
1340                         /* Need a larger buffer.  Query for the right size. */
1341                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1342                                                    NULL, 0);
1343                         if (rc < 0) {
1344                                 dput(dentry);
1345                                 goto out_unlock;
1346                         }
1347                         len = rc;
1348                         context = kmalloc(len+1, GFP_NOFS);
1349                         if (!context) {
1350                                 rc = -ENOMEM;
1351                                 dput(dentry);
1352                                 goto out_unlock;
1353                         }
1354                         context[len] = '\0';
1355                         rc = inode->i_op->getxattr(dentry,
1356                                                    XATTR_NAME_SELINUX,
1357                                                    context, len);
1358                 }
1359                 dput(dentry);
1360                 if (rc < 0) {
1361                         if (rc != -ENODATA) {
1362                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1363                                        "%d for dev=%s ino=%ld\n", __func__,
1364                                        -rc, inode->i_sb->s_id, inode->i_ino);
1365                                 kfree(context);
1366                                 goto out_unlock;
1367                         }
1368                         /* Map ENODATA to the default file SID */
1369                         sid = sbsec->def_sid;
1370                         rc = 0;
1371                 } else {
1372                         rc = security_context_to_sid_default(context, rc, &sid,
1373                                                              sbsec->def_sid,
1374                                                              GFP_NOFS);
1375                         if (rc) {
1376                                 char *dev = inode->i_sb->s_id;
1377                                 unsigned long ino = inode->i_ino;
1378
1379                                 if (rc == -EINVAL) {
1380                                         if (printk_ratelimit())
1381                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1382                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1383                                                         "filesystem in question.\n", ino, dev, context);
1384                                 } else {
1385                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1386                                                "returned %d for dev=%s ino=%ld\n",
1387                                                __func__, context, -rc, dev, ino);
1388                                 }
1389                                 kfree(context);
1390                                 /* Leave with the unlabeled SID */
1391                                 rc = 0;
1392                                 break;
1393                         }
1394                 }
1395                 kfree(context);
1396                 isec->sid = sid;
1397                 break;
1398         case SECURITY_FS_USE_TASK:
1399                 isec->sid = isec->task_sid;
1400                 break;
1401         case SECURITY_FS_USE_TRANS:
1402                 /* Default to the fs SID. */
1403                 isec->sid = sbsec->sid;
1404
1405                 /* Try to obtain a transition SID. */
1406                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1407                 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1408                                              isec->sclass, NULL, &sid);
1409                 if (rc)
1410                         goto out_unlock;
1411                 isec->sid = sid;
1412                 break;
1413         case SECURITY_FS_USE_MNTPOINT:
1414                 isec->sid = sbsec->mntpoint_sid;
1415                 break;
1416         default:
1417                 /* Default to the fs superblock SID. */
1418                 isec->sid = sbsec->sid;
1419
1420                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1421                         if (opt_dentry) {
1422                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1423                                 rc = selinux_proc_get_sid(opt_dentry,
1424                                                           isec->sclass,
1425                                                           &sid);
1426                                 if (rc)
1427                                         goto out_unlock;
1428                                 isec->sid = sid;
1429                         }
1430                 }
1431                 break;
1432         }
1433
1434         isec->initialized = 1;
1435
1436 out_unlock:
1437         mutex_unlock(&isec->lock);
1438 out:
1439         if (isec->sclass == SECCLASS_FILE)
1440                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1441         return rc;
1442 }
1443
1444 /* Convert a Linux signal to an access vector. */
1445 static inline u32 signal_to_av(int sig)
1446 {
1447         u32 perm = 0;
1448
1449         switch (sig) {
1450         case SIGCHLD:
1451                 /* Commonly granted from child to parent. */
1452                 perm = PROCESS__SIGCHLD;
1453                 break;
1454         case SIGKILL:
1455                 /* Cannot be caught or ignored */
1456                 perm = PROCESS__SIGKILL;
1457                 break;
1458         case SIGSTOP:
1459                 /* Cannot be caught or ignored */
1460                 perm = PROCESS__SIGSTOP;
1461                 break;
1462         default:
1463                 /* All other signals. */
1464                 perm = PROCESS__SIGNAL;
1465                 break;
1466         }
1467
1468         return perm;
1469 }
1470
1471 /*
1472  * Check permission between a pair of credentials
1473  * fork check, ptrace check, etc.
1474  */
1475 static int cred_has_perm(const struct cred *actor,
1476                          const struct cred *target,
1477                          u32 perms)
1478 {
1479         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1480
1481         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1482 }
1483
1484 /*
1485  * Check permission between a pair of tasks, e.g. signal checks,
1486  * fork check, ptrace check, etc.
1487  * tsk1 is the actor and tsk2 is the target
1488  * - this uses the default subjective creds of tsk1
1489  */
1490 static int task_has_perm(const struct task_struct *tsk1,
1491                          const struct task_struct *tsk2,
1492                          u32 perms)
1493 {
1494         const struct task_security_struct *__tsec1, *__tsec2;
1495         u32 sid1, sid2;
1496
1497         rcu_read_lock();
1498         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1499         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1500         rcu_read_unlock();
1501         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1502 }
1503
1504 /*
1505  * Check permission between current and another task, e.g. signal checks,
1506  * fork check, ptrace check, etc.
1507  * current is the actor and tsk2 is the target
1508  * - this uses current's subjective creds
1509  */
1510 static int current_has_perm(const struct task_struct *tsk,
1511                             u32 perms)
1512 {
1513         u32 sid, tsid;
1514
1515         sid = current_sid();
1516         tsid = task_sid(tsk);
1517         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1518 }
1519
1520 #if CAP_LAST_CAP > 63
1521 #error Fix SELinux to handle capabilities > 63.
1522 #endif
1523
1524 /* Check whether a task is allowed to use a capability. */
1525 static int cred_has_capability(const struct cred *cred,
1526                                int cap, int audit)
1527 {
1528         struct common_audit_data ad;
1529         struct av_decision avd;
1530         u16 sclass;
1531         u32 sid = cred_sid(cred);
1532         u32 av = CAP_TO_MASK(cap);
1533         int rc;
1534
1535         ad.type = LSM_AUDIT_DATA_CAP;
1536         ad.u.cap = cap;
1537
1538         switch (CAP_TO_INDEX(cap)) {
1539         case 0:
1540                 sclass = SECCLASS_CAPABILITY;
1541                 break;
1542         case 1:
1543                 sclass = SECCLASS_CAPABILITY2;
1544                 break;
1545         default:
1546                 printk(KERN_ERR
1547                        "SELinux:  out of range capability %d\n", cap);
1548                 BUG();
1549                 return -EINVAL;
1550         }
1551
1552         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1553         if (audit == SECURITY_CAP_AUDIT) {
1554                 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1555                 if (rc2)
1556                         return rc2;
1557         }
1558         return rc;
1559 }
1560
1561 /* Check whether a task is allowed to use a system operation. */
1562 static int task_has_system(struct task_struct *tsk,
1563                            u32 perms)
1564 {
1565         u32 sid = task_sid(tsk);
1566
1567         return avc_has_perm(sid, SECINITSID_KERNEL,
1568                             SECCLASS_SYSTEM, perms, NULL);
1569 }
1570
1571 /* Check whether a task has a particular permission to an inode.
1572    The 'adp' parameter is optional and allows other audit
1573    data to be passed (e.g. the dentry). */
1574 static int inode_has_perm(const struct cred *cred,
1575                           struct inode *inode,
1576                           u32 perms,
1577                           struct common_audit_data *adp)
1578 {
1579         struct inode_security_struct *isec;
1580         u32 sid;
1581
1582         validate_creds(cred);
1583
1584         if (unlikely(IS_PRIVATE(inode)))
1585                 return 0;
1586
1587         sid = cred_sid(cred);
1588         isec = inode->i_security;
1589
1590         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1591 }
1592
1593 /* Same as inode_has_perm, but pass explicit audit data containing
1594    the dentry to help the auditing code to more easily generate the
1595    pathname if needed. */
1596 static inline int dentry_has_perm(const struct cred *cred,
1597                                   struct dentry *dentry,
1598                                   u32 av)
1599 {
1600         struct inode *inode = dentry->d_inode;
1601         struct common_audit_data ad;
1602
1603         ad.type = LSM_AUDIT_DATA_DENTRY;
1604         ad.u.dentry = dentry;
1605         return inode_has_perm(cred, inode, av, &ad);
1606 }
1607
1608 /* Same as inode_has_perm, but pass explicit audit data containing
1609    the path to help the auditing code to more easily generate the
1610    pathname if needed. */
1611 static inline int path_has_perm(const struct cred *cred,
1612                                 struct path *path,
1613                                 u32 av)
1614 {
1615         struct inode *inode = path->dentry->d_inode;
1616         struct common_audit_data ad;
1617
1618         ad.type = LSM_AUDIT_DATA_PATH;
1619         ad.u.path = *path;
1620         return inode_has_perm(cred, inode, av, &ad);
1621 }
1622
1623 /* Same as path_has_perm, but uses the inode from the file struct. */
1624 static inline int file_path_has_perm(const struct cred *cred,
1625                                      struct file *file,
1626                                      u32 av)
1627 {
1628         struct common_audit_data ad;
1629
1630         ad.type = LSM_AUDIT_DATA_PATH;
1631         ad.u.path = file->f_path;
1632         return inode_has_perm(cred, file_inode(file), av, &ad);
1633 }
1634
1635 /* Check whether a task can use an open file descriptor to
1636    access an inode in a given way.  Check access to the
1637    descriptor itself, and then use dentry_has_perm to
1638    check a particular permission to the file.
1639    Access to the descriptor is implicitly granted if it
1640    has the same SID as the process.  If av is zero, then
1641    access to the file is not checked, e.g. for cases
1642    where only the descriptor is affected like seek. */
1643 static int file_has_perm(const struct cred *cred,
1644                          struct file *file,
1645                          u32 av)
1646 {
1647         struct file_security_struct *fsec = file->f_security;
1648         struct inode *inode = file_inode(file);
1649         struct common_audit_data ad;
1650         u32 sid = cred_sid(cred);
1651         int rc;
1652
1653         ad.type = LSM_AUDIT_DATA_PATH;
1654         ad.u.path = file->f_path;
1655
1656         if (sid != fsec->sid) {
1657                 rc = avc_has_perm(sid, fsec->sid,
1658                                   SECCLASS_FD,
1659                                   FD__USE,
1660                                   &ad);
1661                 if (rc)
1662                         goto out;
1663         }
1664
1665         /* av is zero if only checking access to the descriptor. */
1666         rc = 0;
1667         if (av)
1668                 rc = inode_has_perm(cred, inode, av, &ad);
1669
1670 out:
1671         return rc;
1672 }
1673
1674 /* Check whether a task can create a file. */
1675 static int may_create(struct inode *dir,
1676                       struct dentry *dentry,
1677                       u16 tclass)
1678 {
1679         const struct task_security_struct *tsec = current_security();
1680         struct inode_security_struct *dsec;
1681         struct superblock_security_struct *sbsec;
1682         u32 sid, newsid;
1683         struct common_audit_data ad;
1684         int rc;
1685
1686         dsec = dir->i_security;
1687         sbsec = dir->i_sb->s_security;
1688
1689         sid = tsec->sid;
1690         newsid = tsec->create_sid;
1691
1692         ad.type = LSM_AUDIT_DATA_DENTRY;
1693         ad.u.dentry = dentry;
1694
1695         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1696                           DIR__ADD_NAME | DIR__SEARCH,
1697                           &ad);
1698         if (rc)
1699                 return rc;
1700
1701         if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
1702                 rc = security_transition_sid(sid, dsec->sid, tclass,
1703                                              &dentry->d_name, &newsid);
1704                 if (rc)
1705                         return rc;
1706         }
1707
1708         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1709         if (rc)
1710                 return rc;
1711
1712         return avc_has_perm(newsid, sbsec->sid,
1713                             SECCLASS_FILESYSTEM,
1714                             FILESYSTEM__ASSOCIATE, &ad);
1715 }
1716
1717 /* Check whether a task can create a key. */
1718 static int may_create_key(u32 ksid,
1719                           struct task_struct *ctx)
1720 {
1721         u32 sid = task_sid(ctx);
1722
1723         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1724 }
1725
1726 #define MAY_LINK        0
1727 #define MAY_UNLINK      1
1728 #define MAY_RMDIR       2
1729
1730 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1731 static int may_link(struct inode *dir,
1732                     struct dentry *dentry,
1733                     int kind)
1734
1735 {
1736         struct inode_security_struct *dsec, *isec;
1737         struct common_audit_data ad;
1738         u32 sid = current_sid();
1739         u32 av;
1740         int rc;
1741
1742         dsec = dir->i_security;
1743         isec = dentry->d_inode->i_security;
1744
1745         ad.type = LSM_AUDIT_DATA_DENTRY;
1746         ad.u.dentry = dentry;
1747
1748         av = DIR__SEARCH;
1749         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1750         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1751         if (rc)
1752                 return rc;
1753
1754         switch (kind) {
1755         case MAY_LINK:
1756                 av = FILE__LINK;
1757                 break;
1758         case MAY_UNLINK:
1759                 av = FILE__UNLINK;
1760                 break;
1761         case MAY_RMDIR:
1762                 av = DIR__RMDIR;
1763                 break;
1764         default:
1765                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1766                         __func__, kind);
1767                 return 0;
1768         }
1769
1770         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1771         return rc;
1772 }
1773
1774 static inline int may_rename(struct inode *old_dir,
1775                              struct dentry *old_dentry,
1776                              struct inode *new_dir,
1777                              struct dentry *new_dentry)
1778 {
1779         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1780         struct common_audit_data ad;
1781         u32 sid = current_sid();
1782         u32 av;
1783         int old_is_dir, new_is_dir;
1784         int rc;
1785
1786         old_dsec = old_dir->i_security;
1787         old_isec = old_dentry->d_inode->i_security;
1788         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1789         new_dsec = new_dir->i_security;
1790
1791         ad.type = LSM_AUDIT_DATA_DENTRY;
1792
1793         ad.u.dentry = old_dentry;
1794         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1795                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1796         if (rc)
1797                 return rc;
1798         rc = avc_has_perm(sid, old_isec->sid,
1799                           old_isec->sclass, FILE__RENAME, &ad);
1800         if (rc)
1801                 return rc;
1802         if (old_is_dir && new_dir != old_dir) {
1803                 rc = avc_has_perm(sid, old_isec->sid,
1804                                   old_isec->sclass, DIR__REPARENT, &ad);
1805                 if (rc)
1806                         return rc;
1807         }
1808
1809         ad.u.dentry = new_dentry;
1810         av = DIR__ADD_NAME | DIR__SEARCH;
1811         if (new_dentry->d_inode)
1812                 av |= DIR__REMOVE_NAME;
1813         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1814         if (rc)
1815                 return rc;
1816         if (new_dentry->d_inode) {
1817                 new_isec = new_dentry->d_inode->i_security;
1818                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1819                 rc = avc_has_perm(sid, new_isec->sid,
1820                                   new_isec->sclass,
1821                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1822                 if (rc)
1823                         return rc;
1824         }
1825
1826         return 0;
1827 }
1828
1829 /* Check whether a task can perform a filesystem operation. */
1830 static int superblock_has_perm(const struct cred *cred,
1831                                struct super_block *sb,
1832                                u32 perms,
1833                                struct common_audit_data *ad)
1834 {
1835         struct superblock_security_struct *sbsec;
1836         u32 sid = cred_sid(cred);
1837
1838         sbsec = sb->s_security;
1839         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1840 }
1841
1842 /* Convert a Linux mode and permission mask to an access vector. */
1843 static inline u32 file_mask_to_av(int mode, int mask)
1844 {
1845         u32 av = 0;
1846
1847         if (!S_ISDIR(mode)) {
1848                 if (mask & MAY_EXEC)
1849                         av |= FILE__EXECUTE;
1850                 if (mask & MAY_READ)
1851                         av |= FILE__READ;
1852
1853                 if (mask & MAY_APPEND)
1854                         av |= FILE__APPEND;
1855                 else if (mask & MAY_WRITE)
1856                         av |= FILE__WRITE;
1857
1858         } else {
1859                 if (mask & MAY_EXEC)
1860                         av |= DIR__SEARCH;
1861                 if (mask & MAY_WRITE)
1862                         av |= DIR__WRITE;
1863                 if (mask & MAY_READ)
1864                         av |= DIR__READ;
1865         }
1866
1867         return av;
1868 }
1869
1870 /* Convert a Linux file to an access vector. */
1871 static inline u32 file_to_av(struct file *file)
1872 {
1873         u32 av = 0;
1874
1875         if (file->f_mode & FMODE_READ)
1876                 av |= FILE__READ;
1877         if (file->f_mode & FMODE_WRITE) {
1878                 if (file->f_flags & O_APPEND)
1879                         av |= FILE__APPEND;
1880                 else
1881                         av |= FILE__WRITE;
1882         }
1883         if (!av) {
1884                 /*
1885                  * Special file opened with flags 3 for ioctl-only use.
1886                  */
1887                 av = FILE__IOCTL;
1888         }
1889
1890         return av;
1891 }
1892
1893 /*
1894  * Convert a file to an access vector and include the correct open
1895  * open permission.
1896  */
1897 static inline u32 open_file_to_av(struct file *file)
1898 {
1899         u32 av = file_to_av(file);
1900
1901         if (selinux_policycap_openperm)
1902                 av |= FILE__OPEN;
1903
1904         return av;
1905 }
1906
1907 /* Hook functions begin here. */
1908
1909 static int selinux_ptrace_access_check(struct task_struct *child,
1910                                      unsigned int mode)
1911 {
1912         int rc;
1913
1914         rc = cap_ptrace_access_check(child, mode);
1915         if (rc)
1916                 return rc;
1917
1918         if (mode & PTRACE_MODE_READ) {
1919                 u32 sid = current_sid();
1920                 u32 csid = task_sid(child);
1921                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1922         }
1923
1924         return current_has_perm(child, PROCESS__PTRACE);
1925 }
1926
1927 static int selinux_ptrace_traceme(struct task_struct *parent)
1928 {
1929         int rc;
1930
1931         rc = cap_ptrace_traceme(parent);
1932         if (rc)
1933                 return rc;
1934
1935         return task_has_perm(parent, current, PROCESS__PTRACE);
1936 }
1937
1938 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1939                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1940 {
1941         int error;
1942
1943         error = current_has_perm(target, PROCESS__GETCAP);
1944         if (error)
1945                 return error;
1946
1947         return cap_capget(target, effective, inheritable, permitted);
1948 }
1949
1950 static int selinux_capset(struct cred *new, const struct cred *old,
1951                           const kernel_cap_t *effective,
1952                           const kernel_cap_t *inheritable,
1953                           const kernel_cap_t *permitted)
1954 {
1955         int error;
1956
1957         error = cap_capset(new, old,
1958                                       effective, inheritable, permitted);
1959         if (error)
1960                 return error;
1961
1962         return cred_has_perm(old, new, PROCESS__SETCAP);
1963 }
1964
1965 /*
1966  * (This comment used to live with the selinux_task_setuid hook,
1967  * which was removed).
1968  *
1969  * Since setuid only affects the current process, and since the SELinux
1970  * controls are not based on the Linux identity attributes, SELinux does not
1971  * need to control this operation.  However, SELinux does control the use of
1972  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1973  */
1974
1975 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
1976                            int cap, int audit)
1977 {
1978         int rc;
1979
1980         rc = cap_capable(cred, ns, cap, audit);
1981         if (rc)
1982                 return rc;
1983
1984         return cred_has_capability(cred, cap, audit);
1985 }
1986
1987 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1988 {
1989         const struct cred *cred = current_cred();
1990         int rc = 0;
1991
1992         if (!sb)
1993                 return 0;
1994
1995         switch (cmds) {
1996         case Q_SYNC:
1997         case Q_QUOTAON:
1998         case Q_QUOTAOFF:
1999         case Q_SETINFO:
2000         case Q_SETQUOTA:
2001                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2002                 break;
2003         case Q_GETFMT:
2004         case Q_GETINFO:
2005         case Q_GETQUOTA:
2006                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2007                 break;
2008         default:
2009                 rc = 0;  /* let the kernel handle invalid cmds */
2010                 break;
2011         }
2012         return rc;
2013 }
2014
2015 static int selinux_quota_on(struct dentry *dentry)
2016 {
2017         const struct cred *cred = current_cred();
2018
2019         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2020 }
2021
2022 static int selinux_syslog(int type)
2023 {
2024         int rc;
2025
2026         switch (type) {
2027         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2028         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2029                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2030                 break;
2031         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2032         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2033         /* Set level of messages printed to console */
2034         case SYSLOG_ACTION_CONSOLE_LEVEL:
2035                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2036                 break;
2037         case SYSLOG_ACTION_CLOSE:       /* Close log */
2038         case SYSLOG_ACTION_OPEN:        /* Open log */
2039         case SYSLOG_ACTION_READ:        /* Read from log */
2040         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
2041         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
2042         default:
2043                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2044                 break;
2045         }
2046         return rc;
2047 }
2048
2049 /*
2050  * Check that a process has enough memory to allocate a new virtual
2051  * mapping. 0 means there is enough memory for the allocation to
2052  * succeed and -ENOMEM implies there is not.
2053  *
2054  * Do not audit the selinux permission check, as this is applied to all
2055  * processes that allocate mappings.
2056  */
2057 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2058 {
2059         int rc, cap_sys_admin = 0;
2060
2061         rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
2062                              SECURITY_CAP_NOAUDIT);
2063         if (rc == 0)
2064                 cap_sys_admin = 1;
2065
2066         return __vm_enough_memory(mm, pages, cap_sys_admin);
2067 }
2068
2069 /* binprm security operations */
2070
2071 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2072 {
2073         const struct task_security_struct *old_tsec;
2074         struct task_security_struct *new_tsec;
2075         struct inode_security_struct *isec;
2076         struct common_audit_data ad;
2077         struct inode *inode = file_inode(bprm->file);
2078         int rc;
2079
2080         rc = cap_bprm_set_creds(bprm);
2081         if (rc)
2082                 return rc;
2083
2084         /* SELinux context only depends on initial program or script and not
2085          * the script interpreter */
2086         if (bprm->cred_prepared)
2087                 return 0;
2088
2089         old_tsec = current_security();
2090         new_tsec = bprm->cred->security;
2091         isec = inode->i_security;
2092
2093         /* Default to the current task SID. */
2094         new_tsec->sid = old_tsec->sid;
2095         new_tsec->osid = old_tsec->sid;
2096
2097         /* Reset fs, key, and sock SIDs on execve. */
2098         new_tsec->create_sid = 0;
2099         new_tsec->keycreate_sid = 0;
2100         new_tsec->sockcreate_sid = 0;
2101
2102         if (old_tsec->exec_sid) {
2103                 new_tsec->sid = old_tsec->exec_sid;
2104                 /* Reset exec SID on execve. */
2105                 new_tsec->exec_sid = 0;
2106
2107                 /*
2108                  * Minimize confusion: if no_new_privs and a transition is
2109                  * explicitly requested, then fail the exec.
2110                  */
2111                 if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)
2112                         return -EPERM;
2113         } else {
2114                 /* Check for a default transition on this program. */
2115                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2116                                              SECCLASS_PROCESS, NULL,
2117                                              &new_tsec->sid);
2118                 if (rc)
2119                         return rc;
2120         }
2121
2122         ad.type = LSM_AUDIT_DATA_PATH;
2123         ad.u.path = bprm->file->f_path;
2124
2125         if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
2126             (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2127                 new_tsec->sid = old_tsec->sid;
2128
2129         if (new_tsec->sid == old_tsec->sid) {
2130                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2131                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2132                 if (rc)
2133                         return rc;
2134         } else {
2135                 /* Check permissions for the transition. */
2136                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2137                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2138                 if (rc)
2139                         return rc;
2140
2141                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2142                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2143                 if (rc)
2144                         return rc;
2145
2146                 /* Check for shared state */
2147                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2148                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2149                                           SECCLASS_PROCESS, PROCESS__SHARE,
2150                                           NULL);
2151                         if (rc)
2152                                 return -EPERM;
2153                 }
2154
2155                 /* Make sure that anyone attempting to ptrace over a task that
2156                  * changes its SID has the appropriate permit */
2157                 if (bprm->unsafe &
2158                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2159                         struct task_struct *tracer;
2160                         struct task_security_struct *sec;
2161                         u32 ptsid = 0;
2162
2163                         rcu_read_lock();
2164                         tracer = ptrace_parent(current);
2165                         if (likely(tracer != NULL)) {
2166                                 sec = __task_cred(tracer)->security;
2167                                 ptsid = sec->sid;
2168                         }
2169                         rcu_read_unlock();
2170
2171                         if (ptsid != 0) {
2172                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2173                                                   SECCLASS_PROCESS,
2174                                                   PROCESS__PTRACE, NULL);
2175                                 if (rc)
2176                                         return -EPERM;
2177                         }
2178                 }
2179
2180                 /* Clear any possibly unsafe personality bits on exec: */
2181                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2182         }
2183
2184         return 0;
2185 }
2186
2187 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2188 {
2189         const struct task_security_struct *tsec = current_security();
2190         u32 sid, osid;
2191         int atsecure = 0;
2192
2193         sid = tsec->sid;
2194         osid = tsec->osid;
2195
2196         if (osid != sid) {
2197                 /* Enable secure mode for SIDs transitions unless
2198                    the noatsecure permission is granted between
2199                    the two SIDs, i.e. ahp returns 0. */
2200                 atsecure = avc_has_perm(osid, sid,
2201                                         SECCLASS_PROCESS,
2202                                         PROCESS__NOATSECURE, NULL);
2203         }
2204
2205         return (atsecure || cap_bprm_secureexec(bprm));
2206 }
2207
2208 static int match_file(const void *p, struct file *file, unsigned fd)
2209 {
2210         return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2211 }
2212
2213 /* Derived from fs/exec.c:flush_old_files. */
2214 static inline void flush_unauthorized_files(const struct cred *cred,
2215                                             struct files_struct *files)
2216 {
2217         struct file *file, *devnull = NULL;
2218         struct tty_struct *tty;
2219         int drop_tty = 0;
2220         unsigned n;
2221
2222         tty = get_current_tty();
2223         if (tty) {
2224                 spin_lock(&tty_files_lock);
2225                 if (!list_empty(&tty->tty_files)) {
2226                         struct tty_file_private *file_priv;
2227
2228                         /* Revalidate access to controlling tty.
2229                            Use file_path_has_perm on the tty path directly
2230                            rather than using file_has_perm, as this particular
2231                            open file may belong to another process and we are
2232                            only interested in the inode-based check here. */
2233                         file_priv = list_first_entry(&tty->tty_files,
2234                                                 struct tty_file_private, list);
2235                         file = file_priv->file;
2236                         if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2237                                 drop_tty = 1;
2238                 }
2239                 spin_unlock(&tty_files_lock);
2240                 tty_kref_put(tty);
2241         }
2242         /* Reset controlling tty. */
2243         if (drop_tty)
2244                 no_tty();
2245
2246         /* Revalidate access to inherited open files. */
2247         n = iterate_fd(files, 0, match_file, cred);
2248         if (!n) /* none found? */
2249                 return;
2250
2251         devnull = dentry_open(&selinux_null, O_RDWR, cred);
2252         if (IS_ERR(devnull))
2253                 devnull = NULL;
2254         /* replace all the matching ones with this */
2255         do {
2256                 replace_fd(n - 1, devnull, 0);
2257         } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2258         if (devnull)
2259                 fput(devnull);
2260 }
2261
2262 /*
2263  * Prepare a process for imminent new credential changes due to exec
2264  */
2265 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2266 {
2267         struct task_security_struct *new_tsec;
2268         struct rlimit *rlim, *initrlim;
2269         int rc, i;
2270
2271         new_tsec = bprm->cred->security;
2272         if (new_tsec->sid == new_tsec->osid)
2273                 return;
2274
2275         /* Close files for which the new task SID is not authorized. */
2276         flush_unauthorized_files(bprm->cred, current->files);
2277
2278         /* Always clear parent death signal on SID transitions. */
2279         current->pdeath_signal = 0;
2280
2281         /* Check whether the new SID can inherit resource limits from the old
2282          * SID.  If not, reset all soft limits to the lower of the current
2283          * task's hard limit and the init task's soft limit.
2284          *
2285          * Note that the setting of hard limits (even to lower them) can be
2286          * controlled by the setrlimit check.  The inclusion of the init task's
2287          * soft limit into the computation is to avoid resetting soft limits
2288          * higher than the default soft limit for cases where the default is
2289          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2290          */
2291         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2292                           PROCESS__RLIMITINH, NULL);
2293         if (rc) {
2294                 /* protect against do_prlimit() */
2295                 task_lock(current);
2296                 for (i = 0; i < RLIM_NLIMITS; i++) {
2297                         rlim = current->signal->rlim + i;
2298                         initrlim = init_task.signal->rlim + i;
2299                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2300                 }
2301                 task_unlock(current);
2302                 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2303         }
2304 }
2305
2306 /*
2307  * Clean up the process immediately after the installation of new credentials
2308  * due to exec
2309  */
2310 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2311 {
2312         const struct task_security_struct *tsec = current_security();
2313         struct itimerval itimer;
2314         u32 osid, sid;
2315         int rc, i;
2316
2317         osid = tsec->osid;
2318         sid = tsec->sid;
2319
2320         if (sid == osid)
2321                 return;
2322
2323         /* Check whether the new SID can inherit signal state from the old SID.
2324          * If not, clear itimers to avoid subsequent signal generation and
2325          * flush and unblock signals.
2326          *
2327          * This must occur _after_ the task SID has been updated so that any
2328          * kill done after the flush will be checked against the new SID.
2329          */
2330         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2331         if (rc) {
2332                 memset(&itimer, 0, sizeof itimer);
2333                 for (i = 0; i < 3; i++)
2334                         do_setitimer(i, &itimer, NULL);
2335                 spin_lock_irq(&current->sighand->siglock);
2336                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2337                         __flush_signals(current);
2338                         flush_signal_handlers(current, 1);
2339                         sigemptyset(&current->blocked);
2340                 }
2341                 spin_unlock_irq(&current->sighand->siglock);
2342         }
2343
2344         /* Wake up the parent if it is waiting so that it can recheck
2345          * wait permission to the new task SID. */
2346         read_lock(&tasklist_lock);
2347         __wake_up_parent(current, current->real_parent);
2348         read_unlock(&tasklist_lock);
2349 }
2350
2351 /* superblock security operations */
2352
2353 static int selinux_sb_alloc_security(struct super_block *sb)
2354 {
2355         return superblock_alloc_security(sb);
2356 }
2357
2358 static void selinux_sb_free_security(struct super_block *sb)
2359 {
2360         superblock_free_security(sb);
2361 }
2362
2363 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2364 {
2365         if (plen > olen)
2366                 return 0;
2367
2368         return !memcmp(prefix, option, plen);
2369 }
2370
2371 static inline int selinux_option(char *option, int len)
2372 {
2373         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2374                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2375                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2376                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2377                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2378 }
2379
2380 static inline void take_option(char **to, char *from, int *first, int len)
2381 {
2382         if (!*first) {
2383                 **to = ',';
2384                 *to += 1;
2385         } else
2386                 *first = 0;
2387         memcpy(*to, from, len);
2388         *to += len;
2389 }
2390
2391 static inline void take_selinux_option(char **to, char *from, int *first,
2392                                        int len)
2393 {
2394         int current_size = 0;
2395
2396         if (!*first) {
2397                 **to = '|';
2398                 *to += 1;
2399         } else
2400                 *first = 0;
2401
2402         while (current_size < len) {
2403                 if (*from != '"') {
2404                         **to = *from;
2405                         *to += 1;
2406                 }
2407                 from += 1;
2408                 current_size += 1;
2409         }
2410 }
2411
2412 static int selinux_sb_copy_data(char *orig, char *copy)
2413 {
2414         int fnosec, fsec, rc = 0;
2415         char *in_save, *in_curr, *in_end;
2416         char *sec_curr, *nosec_save, *nosec;
2417         int open_quote = 0;
2418
2419         in_curr = orig;
2420         sec_curr = copy;
2421
2422         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2423         if (!nosec) {
2424                 rc = -ENOMEM;
2425                 goto out;
2426         }
2427
2428         nosec_save = nosec;
2429         fnosec = fsec = 1;
2430         in_save = in_end = orig;
2431
2432         do {
2433                 if (*in_end == '"')
2434                         open_quote = !open_quote;
2435                 if ((*in_end == ',' && open_quote == 0) ||
2436                                 *in_end == '\0') {
2437                         int len = in_end - in_curr;
2438
2439                         if (selinux_option(in_curr, len))
2440                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2441                         else
2442                                 take_option(&nosec, in_curr, &fnosec, len);
2443
2444                         in_curr = in_end + 1;
2445                 }
2446         } while (*in_end++);
2447
2448         strcpy(in_save, nosec_save);
2449         free_page((unsigned long)nosec_save);
2450 out:
2451         return rc;
2452 }
2453
2454 static int selinux_sb_remount(struct super_block *sb, void *data)
2455 {
2456         int rc, i, *flags;
2457         struct security_mnt_opts opts;
2458         char *secdata, **mount_options;
2459         struct superblock_security_struct *sbsec = sb->s_security;
2460
2461         if (!(sbsec->flags & SE_SBINITIALIZED))
2462                 return 0;
2463
2464         if (!data)
2465                 return 0;
2466
2467         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2468                 return 0;
2469
2470         security_init_mnt_opts(&opts);
2471         secdata = alloc_secdata();
2472         if (!secdata)
2473                 return -ENOMEM;
2474         rc = selinux_sb_copy_data(data, secdata);
2475         if (rc)
2476                 goto out_free_secdata;
2477
2478         rc = selinux_parse_opts_str(secdata, &opts);
2479         if (rc)
2480                 goto out_free_secdata;
2481
2482         mount_options = opts.mnt_opts;
2483         flags = opts.mnt_opts_flags;
2484
2485         for (i = 0; i < opts.num_mnt_opts; i++) {
2486                 u32 sid;
2487                 size_t len;
2488
2489                 if (flags[i] == SBLABEL_MNT)
2490                         continue;
2491                 len = strlen(mount_options[i]);
2492                 rc = security_context_to_sid(mount_options[i], len, &sid,
2493                                              GFP_KERNEL);
2494                 if (rc) {
2495                         printk(KERN_WARNING "SELinux: security_context_to_sid"
2496                                "(%s) failed for (dev %s, type %s) errno=%d\n",
2497                                mount_options[i], sb->s_id, sb->s_type->name, rc);
2498                         goto out_free_opts;
2499                 }
2500                 rc = -EINVAL;
2501                 switch (flags[i]) {
2502                 case FSCONTEXT_MNT:
2503                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2504                                 goto out_bad_option;
2505                         break;
2506                 case CONTEXT_MNT:
2507                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2508                                 goto out_bad_option;
2509                         break;
2510                 case ROOTCONTEXT_MNT: {
2511                         struct inode_security_struct *root_isec;
2512                         root_isec = sb->s_root->d_inode->i_security;
2513
2514                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2515                                 goto out_bad_option;
2516                         break;
2517                 }
2518                 case DEFCONTEXT_MNT:
2519                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2520                                 goto out_bad_option;
2521                         break;
2522                 default:
2523                         goto out_free_opts;
2524                 }
2525         }
2526
2527         rc = 0;
2528 out_free_opts:
2529         security_free_mnt_opts(&opts);
2530 out_free_secdata:
2531         free_secdata(secdata);
2532         return rc;
2533 out_bad_option:
2534         printk(KERN_WARNING "SELinux: unable to change security options "
2535                "during remount (dev %s, type=%s)\n", sb->s_id,
2536                sb->s_type->name);
2537         goto out_free_opts;
2538 }
2539
2540 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2541 {
2542         const struct cred *cred = current_cred();
2543         struct common_audit_data ad;
2544         int rc;
2545
2546         rc = superblock_doinit(sb, data);
2547         if (rc)
2548                 return rc;
2549
2550         /* Allow all mounts performed by the kernel */
2551         if (flags & MS_KERNMOUNT)
2552                 return 0;
2553
2554         ad.type = LSM_AUDIT_DATA_DENTRY;
2555         ad.u.dentry = sb->s_root;
2556         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2557 }
2558
2559 static int selinux_sb_statfs(struct dentry *dentry)
2560 {
2561         const struct cred *cred = current_cred();
2562         struct common_audit_data ad;
2563
2564         ad.type = LSM_AUDIT_DATA_DENTRY;
2565         ad.u.dentry = dentry->d_sb->s_root;
2566         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2567 }
2568
2569 static int selinux_mount(const char *dev_name,
2570                          struct path *path,
2571                          const char *type,
2572                          unsigned long flags,
2573                          void *data)
2574 {
2575         const struct cred *cred = current_cred();
2576
2577         if (flags & MS_REMOUNT)
2578                 return superblock_has_perm(cred, path->dentry->d_sb,
2579                                            FILESYSTEM__REMOUNT, NULL);
2580         else
2581                 return path_has_perm(cred, path, FILE__MOUNTON);
2582 }
2583
2584 static int selinux_umount(struct vfsmount *mnt, int flags)
2585 {
2586         const struct cred *cred = current_cred();
2587
2588         return superblock_has_perm(cred, mnt->mnt_sb,
2589                                    FILESYSTEM__UNMOUNT, NULL);
2590 }
2591
2592 /* inode security operations */
2593
2594 static int selinux_inode_alloc_security(struct inode *inode)
2595 {
2596         return inode_alloc_security(inode);
2597 }
2598
2599 static void selinux_inode_free_security(struct inode *inode)
2600 {
2601         inode_free_security(inode);
2602 }
2603
2604 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2605                                         struct qstr *name, void **ctx,
2606                                         u32 *ctxlen)
2607 {
2608         const struct cred *cred = current_cred();
2609         struct task_security_struct *tsec;
2610         struct inode_security_struct *dsec;
2611         struct superblock_security_struct *sbsec;
2612         struct inode *dir = dentry->d_parent->d_inode;
2613         u32 newsid;
2614         int rc;
2615
2616         tsec = cred->security;
2617         dsec = dir->i_security;
2618         sbsec = dir->i_sb->s_security;
2619
2620         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2621                 newsid = tsec->create_sid;
2622         } else {
2623                 rc = security_transition_sid(tsec->sid, dsec->sid,
2624                                              inode_mode_to_security_class(mode),
2625                                              name,
2626                                              &newsid);
2627                 if (rc) {
2628                         printk(KERN_WARNING
2629                                 "%s: security_transition_sid failed, rc=%d\n",
2630                                __func__, -rc);
2631                         return rc;
2632                 }
2633         }
2634
2635         return security_sid_to_context(newsid, (char **)ctx, ctxlen);
2636 }
2637
2638 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2639                                        const struct qstr *qstr,
2640                                        const char **name,
2641                                        void **value, size_t *len)
2642 {
2643         const struct task_security_struct *tsec = current_security();
2644         struct inode_security_struct *dsec;
2645         struct superblock_security_struct *sbsec;
2646         u32 sid, newsid, clen;
2647         int rc;
2648         char *context;
2649
2650         dsec = dir->i_security;
2651         sbsec = dir->i_sb->s_security;
2652
2653         sid = tsec->sid;
2654         newsid = tsec->create_sid;
2655
2656         if ((sbsec->flags & SE_SBINITIALIZED) &&
2657             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2658                 newsid = sbsec->mntpoint_sid;
2659         else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
2660                 rc = security_transition_sid(sid, dsec->sid,
2661                                              inode_mode_to_security_class(inode->i_mode),
2662                                              qstr, &newsid);
2663                 if (rc) {
2664                         printk(KERN_WARNING "%s:  "
2665                                "security_transition_sid failed, rc=%d (dev=%s "
2666                                "ino=%ld)\n",
2667                                __func__,
2668                                -rc, inode->i_sb->s_id, inode->i_ino);
2669                         return rc;
2670                 }
2671         }
2672
2673         /* Possibly defer initialization to selinux_complete_init. */
2674         if (sbsec->flags & SE_SBINITIALIZED) {
2675                 struct inode_security_struct *isec = inode->i_security;
2676                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2677                 isec->sid = newsid;
2678                 isec->initialized = 1;
2679         }
2680
2681         if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2682                 return -EOPNOTSUPP;
2683
2684         if (name)
2685                 *name = XATTR_SELINUX_SUFFIX;
2686
2687         if (value && len) {
2688                 rc = security_sid_to_context_force(newsid, &context, &clen);
2689                 if (rc)
2690                         return rc;
2691                 *value = context;
2692                 *len = clen;
2693         }
2694
2695         return 0;
2696 }
2697
2698 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2699 {
2700         return may_create(dir, dentry, SECCLASS_FILE);
2701 }
2702
2703 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2704 {
2705         return may_link(dir, old_dentry, MAY_LINK);
2706 }
2707
2708 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2709 {
2710         return may_link(dir, dentry, MAY_UNLINK);
2711 }
2712
2713 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2714 {
2715         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2716 }
2717
2718 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2719 {
2720         return may_create(dir, dentry, SECCLASS_DIR);
2721 }
2722
2723 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2724 {
2725         return may_link(dir, dentry, MAY_RMDIR);
2726 }
2727
2728 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2729 {
2730         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2731 }
2732
2733 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2734                                 struct inode *new_inode, struct dentry *new_dentry)
2735 {
2736         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2737 }
2738
2739 static int selinux_inode_readlink(struct dentry *dentry)
2740 {
2741         const struct cred *cred = current_cred();
2742
2743         return dentry_has_perm(cred, dentry, FILE__READ);
2744 }
2745
2746 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2747 {
2748         const struct cred *cred = current_cred();
2749
2750         return dentry_has_perm(cred, dentry, FILE__READ);
2751 }
2752
2753 static noinline int audit_inode_permission(struct inode *inode,
2754                                            u32 perms, u32 audited, u32 denied,
2755                                            unsigned flags)
2756 {
2757         struct common_audit_data ad;
2758         struct inode_security_struct *isec = inode->i_security;
2759         int rc;
2760
2761         ad.type = LSM_AUDIT_DATA_INODE;
2762         ad.u.inode = inode;
2763
2764         rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2765                             audited, denied, &ad, flags);
2766         if (rc)
2767                 return rc;
2768         return 0;
2769 }
2770
2771 static int selinux_inode_permission(struct inode *inode, int mask)
2772 {
2773         const struct cred *cred = current_cred();
2774         u32 perms;
2775         bool from_access;
2776         unsigned flags = mask & MAY_NOT_BLOCK;
2777         struct inode_security_struct *isec;
2778         u32 sid;
2779         struct av_decision avd;
2780         int rc, rc2;
2781         u32 audited, denied;
2782
2783         from_access = mask & MAY_ACCESS;
2784         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2785
2786         /* No permission to check.  Existence test. */
2787         if (!mask)
2788                 return 0;
2789
2790         validate_creds(cred);
2791
2792         if (unlikely(IS_PRIVATE(inode)))
2793                 return 0;
2794
2795         perms = file_mask_to_av(inode->i_mode, mask);
2796
2797         sid = cred_sid(cred);
2798         isec = inode->i_security;
2799
2800         rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
2801         audited = avc_audit_required(perms, &avd, rc,
2802                                      from_access ? FILE__AUDIT_ACCESS : 0,
2803                                      &denied);
2804         if (likely(!audited))
2805                 return rc;
2806
2807         rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2808         if (rc2)
2809                 return rc2;
2810         return rc;
2811 }
2812
2813 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2814 {
2815         const struct cred *cred = current_cred();
2816         unsigned int ia_valid = iattr->ia_valid;
2817         __u32 av = FILE__WRITE;
2818
2819         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2820         if (ia_valid & ATTR_FORCE) {
2821                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2822                               ATTR_FORCE);
2823                 if (!ia_valid)
2824                         return 0;
2825         }
2826
2827         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2828                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2829                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2830
2831         if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2832                 av |= FILE__OPEN;
2833
2834         return dentry_has_perm(cred, dentry, av);
2835 }
2836
2837 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2838 {
2839         const struct cred *cred = current_cred();
2840         struct path path;
2841
2842         path.dentry = dentry;
2843         path.mnt = mnt;
2844
2845         return path_has_perm(cred, &path, FILE__GETATTR);
2846 }
2847
2848 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2849 {
2850         const struct cred *cred = current_cred();
2851
2852         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2853                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2854                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2855                         if (!capable(CAP_SETFCAP))
2856                                 return -EPERM;
2857                 } else if (!capable(CAP_SYS_ADMIN)) {
2858                         /* A different attribute in the security namespace.
2859                            Restrict to administrator. */
2860                         return -EPERM;
2861                 }
2862         }
2863
2864         /* Not an attribute we recognize, so just check the
2865            ordinary setattr permission. */
2866         return dentry_has_perm(cred, dentry, FILE__SETATTR);
2867 }
2868
2869 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2870                                   const void *value, size_t size, int flags)
2871 {
2872         struct inode *inode = dentry->d_inode;
2873         struct inode_security_struct *isec = inode->i_security;
2874         struct superblock_security_struct *sbsec;
2875         struct common_audit_data ad;
2876         u32 newsid, sid = current_sid();
2877         int rc = 0;
2878
2879         if (strcmp(name, XATTR_NAME_SELINUX))
2880                 return selinux_inode_setotherxattr(dentry, name);
2881
2882         sbsec = inode->i_sb->s_security;
2883         if (!(sbsec->flags & SBLABEL_MNT))
2884                 return -EOPNOTSUPP;
2885
2886         if (!inode_owner_or_capable(inode))
2887                 return -EPERM;
2888
2889         ad.type = LSM_AUDIT_DATA_DENTRY;
2890         ad.u.dentry = dentry;
2891
2892         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2893                           FILE__RELABELFROM, &ad);
2894         if (rc)
2895                 return rc;
2896
2897         rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
2898         if (rc == -EINVAL) {
2899                 if (!capable(CAP_MAC_ADMIN)) {
2900                         struct audit_buffer *ab;
2901                         size_t audit_size;
2902                         const char *str;
2903
2904                         /* We strip a nul only if it is at the end, otherwise the
2905                          * context contains a nul and we should audit that */
2906                         if (value) {
2907                                 str = value;
2908                                 if (str[size - 1] == '\0')
2909                                         audit_size = size - 1;
2910                                 else
2911                                         audit_size = size;
2912                         } else {
2913                                 str = "";
2914                                 audit_size = 0;
2915                         }
2916                         ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
2917                         audit_log_format(ab, "op=setxattr invalid_context=");
2918                         audit_log_n_untrustedstring(ab, value, audit_size);
2919                         audit_log_end(ab);
2920
2921                         return rc;
2922                 }
2923                 rc = security_context_to_sid_force(value, size, &newsid);
2924         }
2925         if (rc)
2926                 return rc;
2927
2928         rc = avc_has_perm(sid, newsid, isec->sclass,
2929                           FILE__RELABELTO, &ad);
2930         if (rc)
2931                 return rc;
2932
2933         rc = security_validate_transition(isec->sid, newsid, sid,
2934                                           isec->sclass);
2935         if (rc)
2936                 return rc;
2937
2938         return avc_has_perm(newsid,
2939                             sbsec->sid,
2940                             SECCLASS_FILESYSTEM,
2941                             FILESYSTEM__ASSOCIATE,
2942                             &ad);
2943 }
2944
2945 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2946                                         const void *value, size_t size,
2947                                         int flags)
2948 {
2949         struct inode *inode = dentry->d_inode;
2950         struct inode_security_struct *isec = inode->i_security;
2951         u32 newsid;
2952         int rc;
2953
2954         if (strcmp(name, XATTR_NAME_SELINUX)) {
2955                 /* Not an attribute we recognize, so nothing to do. */
2956                 return;
2957         }
2958
2959         rc = security_context_to_sid_force(value, size, &newsid);
2960         if (rc) {
2961                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2962                        "for (%s, %lu), rc=%d\n",
2963                        inode->i_sb->s_id, inode->i_ino, -rc);
2964                 return;
2965         }
2966
2967         isec->sclass = inode_mode_to_security_class(inode->i_mode);
2968         isec->sid = newsid;
2969         isec->initialized = 1;
2970
2971         return;
2972 }
2973
2974 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2975 {
2976         const struct cred *cred = current_cred();
2977
2978         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2979 }
2980
2981 static int selinux_inode_listxattr(struct dentry *dentry)
2982 {
2983         const struct cred *cred = current_cred();
2984
2985         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2986 }
2987
2988 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2989 {
2990         if (strcmp(name, XATTR_NAME_SELINUX))
2991                 return selinux_inode_setotherxattr(dentry, name);
2992
2993         /* No one is allowed to remove a SELinux security label.
2994            You can change the label, but all data must be labeled. */
2995         return -EACCES;
2996 }
2997
2998 /*
2999  * Copy the inode security context value to the user.
3000  *
3001  * Permission check is handled by selinux_inode_getxattr hook.
3002  */
3003 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
3004 {
3005         u32 size;
3006         int error;
3007         char *context = NULL;
3008         struct inode_security_struct *isec = inode->i_security;
3009
3010         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3011                 return -EOPNOTSUPP;
3012
3013         /*
3014          * If the caller has CAP_MAC_ADMIN, then get the raw context
3015          * value even if it is not defined by current policy; otherwise,
3016          * use the in-core value under current policy.
3017          * Use the non-auditing forms of the permission checks since
3018          * getxattr may be called by unprivileged processes commonly
3019          * and lack of permission just means that we fall back to the
3020          * in-core context value, not a denial.
3021          */
3022         error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3023                                 SECURITY_CAP_NOAUDIT);
3024         if (!error)
3025                 error = security_sid_to_context_force(isec->sid, &context,
3026                                                       &size);
3027         else
3028                 error = security_sid_to_context(isec->sid, &context, &size);
3029         if (error)
3030                 return error;
3031         error = size;
3032         if (alloc) {
3033                 *buffer = context;
3034                 goto out_nofree;
3035         }
3036         kfree(context);
3037 out_nofree:
3038         return error;
3039 }
3040
3041 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3042                                      const void *value, size_t size, int flags)
3043 {
3044         struct inode_security_struct *isec = inode->i_security;
3045         u32 newsid;
3046         int rc;
3047
3048         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3049                 return -EOPNOTSUPP;
3050
3051         if (!value || !size)
3052                 return -EACCES;
3053
3054         rc = security_context_to_sid((void *)value, size, &newsid, GFP_KERNEL);
3055         if (rc)
3056                 return rc;
3057
3058         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3059         isec->sid = newsid;
3060         isec->initialized = 1;
3061         return 0;
3062 }
3063
3064 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3065 {
3066         const int len = sizeof(XATTR_NAME_SELINUX);
3067         if (buffer && len <= buffer_size)
3068                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3069         return len;
3070 }
3071
3072 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
3073 {
3074         struct inode_security_struct *isec = inode->i_security;
3075         *secid = isec->sid;
3076 }
3077
3078 /* file security operations */
3079
3080 static int selinux_revalidate_file_permission(struct file *file, int mask)
3081 {
3082         const struct cred *cred = current_cred();
3083         struct inode *inode = file_inode(file);
3084
3085         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3086         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3087                 mask |= MAY_APPEND;
3088
3089         return file_has_perm(cred, file,
3090                              file_mask_to_av(inode->i_mode, mask));
3091 }
3092
3093 static int selinux_file_permission(struct file *file, int mask)
3094 {
3095         struct inode *inode = file_inode(file);
3096         struct file_security_struct *fsec = file->f_security;
3097         struct inode_security_struct *isec = inode->i_security;
3098         u32 sid = current_sid();
3099
3100         if (!mask)
3101                 /* No permission to check.  Existence test. */
3102                 return 0;
3103
3104         if (sid == fsec->sid && fsec->isid == isec->sid &&
3105             fsec->pseqno == avc_policy_seqno())
3106                 /* No change since file_open check. */
3107                 return 0;
3108
3109         return selinux_revalidate_file_permission(file, mask);
3110 }
3111
3112 static int selinux_file_alloc_security(struct file *file)
3113 {
3114         return file_alloc_security(file);
3115 }
3116
3117 static void selinux_file_free_security(struct file *file)
3118 {
3119         file_free_security(file);
3120 }
3121
3122 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3123                               unsigned long arg)
3124 {
3125         const struct cred *cred = current_cred();
3126         int error = 0;
3127
3128         switch (cmd) {
3129         case FIONREAD:
3130         /* fall through */
3131         case FIBMAP:
3132         /* fall through */
3133         case FIGETBSZ:
3134         /* fall through */
3135         case FS_IOC_GETFLAGS:
3136         /* fall through */
3137         case FS_IOC_GETVERSION:
3138                 error = file_has_perm(cred, file, FILE__GETATTR);
3139                 break;
3140
3141         case FS_IOC_SETFLAGS:
3142         /* fall through */
3143         case FS_IOC_SETVERSION:
3144                 error = file_has_perm(cred, file, FILE__SETATTR);
3145                 break;
3146
3147         /* sys_ioctl() checks */
3148         case FIONBIO:
3149         /* fall through */
3150         case FIOASYNC:
3151                 error = file_has_perm(cred, file, 0);
3152                 break;
3153
3154         case KDSKBENT:
3155         case KDSKBSENT:
3156                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3157                                             SECURITY_CAP_AUDIT);
3158                 break;
3159
3160         /* default case assumes that the command will go
3161          * to the file's ioctl() function.
3162          */
3163         default:
3164                 error = file_has_perm(cred, file, FILE__IOCTL);
3165         }
3166         return error;
3167 }
3168
3169 static int default_noexec;
3170
3171 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3172 {
3173         const struct cred *cred = current_cred();
3174         int rc = 0;
3175
3176         if (default_noexec &&
3177             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3178                 /*
3179                  * We are making executable an anonymous mapping or a
3180                  * private file mapping that will also be writable.
3181                  * This has an additional check.
3182                  */
3183                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3184                 if (rc)
3185                         goto error;
3186         }
3187
3188         if (file) {
3189                 /* read access is always possible with a mapping */
3190                 u32 av = FILE__READ;
3191
3192                 /* write access only matters if the mapping is shared */
3193                 if (shared && (prot & PROT_WRITE))
3194                         av |= FILE__WRITE;
3195
3196                 if (prot & PROT_EXEC)
3197                         av |= FILE__EXECUTE;
3198
3199                 return file_has_perm(cred, file, av);
3200         }
3201
3202 error:
3203         return rc;
3204 }
3205
3206 static int selinux_mmap_addr(unsigned long addr)
3207 {
3208         int rc = 0;
3209         u32 sid = current_sid();
3210
3211         /*
3212          * notice that we are intentionally putting the SELinux check before
3213          * the secondary cap_file_mmap check.  This is such a likely attempt
3214          * at bad behaviour/exploit that we always want to get the AVC, even
3215          * if DAC would have also denied the operation.
3216          */
3217         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3218                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3219                                   MEMPROTECT__MMAP_ZERO, NULL);
3220                 if (rc)
3221                         return rc;
3222         }
3223
3224         /* do DAC check on address space usage */
3225         return cap_mmap_addr(addr);
3226 }
3227
3228 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3229                              unsigned long prot, unsigned long flags)
3230 {
3231         if (selinux_checkreqprot)
3232                 prot = reqprot;
3233
3234         return file_map_prot_check(file, prot,
3235                                    (flags & MAP_TYPE) == MAP_SHARED);
3236 }
3237
3238 static int selinux_file_mprotect(struct vm_area_struct *vma,
3239                                  unsigned long reqprot,
3240                                  unsigned long prot)
3241 {
3242         const struct cred *cred = current_cred();
3243
3244         if (selinux_checkreqprot)
3245                 prot = reqprot;
3246
3247         if (default_noexec &&
3248             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3249                 int rc = 0;
3250                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3251                     vma->vm_end <= vma->vm_mm->brk) {
3252                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3253                 } else if (!vma->vm_file &&
3254                            vma->vm_start <= vma->vm_mm->start_stack &&
3255                            vma->vm_end >= vma->vm_mm->start_stack) {
3256                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3257                 } else if (vma->vm_file && vma->anon_vma) {
3258                         /*
3259                          * We are making executable a file mapping that has
3260                          * had some COW done. Since pages might have been
3261                          * written, check ability to execute the possibly
3262                          * modified content.  This typically should only
3263                          * occur for text relocations.
3264                          */
3265                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3266                 }
3267                 if (rc)
3268                         return rc;
3269         }
3270
3271         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3272 }
3273
3274 static int selinux_file_lock(struct file *file, unsigned int cmd)
3275 {
3276         const struct cred *cred = current_cred();
3277
3278         return file_has_perm(cred, file, FILE__LOCK);
3279 }
3280
3281 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3282                               unsigned long arg)
3283 {
3284         const struct cred *cred = current_cred();
3285         int err = 0;
3286
3287         switch (cmd) {
3288         case F_SETFL:
3289                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3290                         err = file_has_perm(cred, file, FILE__WRITE);
3291                         break;
3292                 }
3293                 /* fall through */
3294         case F_SETOWN:
3295         case F_SETSIG:
3296         case F_GETFL:
3297         case F_GETOWN:
3298         case F_GETSIG:
3299         case F_GETOWNER_UIDS:
3300                 /* Just check FD__USE permission */
3301                 err = file_has_perm(cred, file, 0);
3302                 break;
3303         case F_GETLK:
3304         case F_SETLK:
3305         case F_SETLKW:
3306 #if BITS_PER_LONG == 32
3307         case F_GETLK64:
3308         case F_SETLK64:
3309         case F_SETLKW64:
3310 #endif
3311                 err = file_has_perm(cred, file, FILE__LOCK);
3312                 break;
3313         }
3314
3315         return err;
3316 }
3317
3318 static int selinux_file_set_fowner(struct file *file)
3319 {
3320         struct file_security_struct *fsec;
3321
3322         fsec = file->f_security;
3323         fsec->fown_sid = current_sid();
3324
3325         return 0;
3326 }
3327
3328 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3329                                        struct fown_struct *fown, int signum)
3330 {
3331         struct file *file;
3332         u32 sid = task_sid(tsk);
3333         u32 perm;
3334         struct file_security_struct *fsec;
3335
3336         /* struct fown_struct is never outside the context of a struct file */
3337         file = container_of(fown, struct file, f_owner);
3338
3339         fsec = file->f_security;
3340
3341         if (!signum)
3342                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3343         else
3344                 perm = signal_to_av(signum);
3345
3346         return avc_has_perm(fsec->fown_sid, sid,
3347                             SECCLASS_PROCESS, perm, NULL);
3348 }
3349
3350 static int selinux_file_receive(struct file *file)
3351 {
3352         const struct cred *cred = current_cred();
3353
3354         return file_has_perm(cred, file, file_to_av(file));
3355 }
3356
3357 static int selinux_file_open(struct file *file, const struct cred *cred)
3358 {
3359         struct file_security_struct *fsec;
3360         struct inode_security_struct *isec;
3361
3362         fsec = file->f_security;
3363         isec = file_inode(file)->i_security;
3364         /*
3365          * Save inode label and policy sequence number
3366          * at open-time so that selinux_file_permission
3367          * can determine whether revalidation is necessary.
3368          * Task label is already saved in the file security
3369          * struct as its SID.
3370          */
3371         fsec->isid = isec->sid;
3372         fsec->pseqno = avc_policy_seqno();
3373         /*
3374          * Since the inode label or policy seqno may have changed
3375          * between the selinux_inode_permission check and the saving
3376          * of state above, recheck that access is still permitted.
3377          * Otherwise, access might never be revalidated against the
3378          * new inode label or new policy.
3379          * This check is not redundant - do not remove.
3380          */
3381         return file_path_has_perm(cred, file, open_file_to_av(file));
3382 }
3383
3384 /* task security operations */
3385
3386 static int selinux_task_create(unsigned long clone_flags)
3387 {
3388         return current_has_perm(current, PROCESS__FORK);
3389 }
3390
3391 /*
3392  * allocate the SELinux part of blank credentials
3393  */
3394 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3395 {
3396         struct task_security_struct *tsec;
3397
3398         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3399         if (!tsec)
3400                 return -ENOMEM;
3401
3402         cred->security = tsec;
3403         return 0;
3404 }
3405
3406 /*
3407  * detach and free the LSM part of a set of credentials
3408  */
3409 static void selinux_cred_free(struct cred *cred)
3410 {
3411         struct task_security_struct *tsec = cred->security;
3412
3413         /*
3414          * cred->security == NULL if security_cred_alloc_blank() or
3415          * security_prepare_creds() returned an error.
3416          */
3417         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3418         cred->security = (void *) 0x7UL;
3419         kfree(tsec);
3420 }
3421
3422 /*
3423  * prepare a new set of credentials for modification
3424  */
3425 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3426                                 gfp_t gfp)
3427 {
3428         const struct task_security_struct *old_tsec;
3429         struct task_security_struct *tsec;
3430
3431         old_tsec = old->security;
3432
3433         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3434         if (!tsec)
3435                 return -ENOMEM;
3436
3437         new->security = tsec;
3438         return 0;
3439 }
3440
3441 /*
3442  * transfer the SELinux data to a blank set of creds
3443  */
3444 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3445 {
3446         const struct task_security_struct *old_tsec = old->security;
3447         struct task_security_struct *tsec = new->security;
3448
3449         *tsec = *old_tsec;
3450 }
3451
3452 /*
3453  * set the security data for a kernel service
3454  * - all the creation contexts are set to unlabelled
3455  */
3456 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3457 {
3458         struct task_security_struct *tsec = new->security;
3459         u32 sid = current_sid();
3460         int ret;
3461
3462         ret = avc_has_perm(sid, secid,
3463                            SECCLASS_KERNEL_SERVICE,
3464                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3465                            NULL);
3466         if (ret == 0) {
3467                 tsec->sid = secid;
3468                 tsec->create_sid = 0;
3469                 tsec->keycreate_sid = 0;
3470                 tsec->sockcreate_sid = 0;
3471         }
3472         return ret;
3473 }
3474
3475 /*
3476  * set the file creation context in a security record to the same as the
3477  * objective context of the specified inode
3478  */
3479 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3480 {
3481         struct inode_security_struct *isec = inode->i_security;
3482         struct task_security_struct *tsec = new->security;
3483         u32 sid = current_sid();
3484         int ret;
3485
3486         ret = avc_has_perm(sid, isec->sid,
3487                            SECCLASS_KERNEL_SERVICE,
3488                            KERNEL_SERVICE__CREATE_FILES_AS,
3489                            NULL);
3490
3491         if (ret == 0)
3492                 tsec->create_sid = isec->sid;
3493         return ret;
3494 }
3495
3496 static int selinux_kernel_module_request(char *kmod_name)
3497 {
3498         u32 sid;
3499         struct common_audit_data ad;
3500
3501         sid = task_sid(current);
3502
3503         ad.type = LSM_AUDIT_DATA_KMOD;
3504         ad.u.kmod_name = kmod_name;
3505
3506         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3507                             SYSTEM__MODULE_REQUEST, &ad);
3508 }
3509
3510 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3511 {
3512         return current_has_perm(p, PROCESS__SETPGID);
3513 }
3514
3515 static int selinux_task_getpgid(struct task_struct *p)
3516 {
3517         return current_has_perm(p, PROCESS__GETPGID);
3518 }
3519
3520 static int selinux_task_getsid(struct task_struct *p)
3521 {
3522         return current_has_perm(p, PROCESS__GETSESSION);
3523 }
3524
3525 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3526 {
3527         *secid = task_sid(p);
3528 }
3529
3530 static int selinux_task_setnice(struct task_struct *p, int nice)
3531 {
3532         int rc;
3533
3534         rc = cap_task_setnice(p, nice);
3535         if (rc)
3536                 return rc;
3537
3538         return current_has_perm(p, PROCESS__SETSCHED);
3539 }
3540
3541 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3542 {
3543         int rc;
3544
3545         rc = cap_task_setioprio(p, ioprio);
3546         if (rc)
3547                 return rc;
3548
3549         return current_has_perm(p, PROCESS__SETSCHED);
3550 }
3551
3552 static int selinux_task_getioprio(struct task_struct *p)
3553 {
3554         return current_has_perm(p, PROCESS__GETSCHED);
3555 }
3556
3557 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3558                 struct rlimit *new_rlim)
3559 {
3560         struct rlimit *old_rlim = p->signal->rlim + resource;
3561
3562         /* Control the ability to change the hard limit (whether
3563            lowering or raising it), so that the hard limit can
3564            later be used as a safe reset point for the soft limit
3565            upon context transitions.  See selinux_bprm_committing_creds. */
3566         if (old_rlim->rlim_max != new_rlim->rlim_max)
3567                 return current_has_perm(p, PROCESS__SETRLIMIT);
3568
3569         return 0;
3570 }
3571
3572 static int selinux_task_setscheduler(struct task_struct *p)
3573 {
3574         int rc;
3575
3576         rc = cap_task_setscheduler(p);
3577         if (rc)
3578                 return rc;
3579
3580         return current_has_perm(p, PROCESS__SETSCHED);
3581 }
3582
3583 static int selinux_task_getscheduler(struct task_struct *p)
3584 {
3585         return current_has_perm(p, PROCESS__GETSCHED);
3586 }
3587
3588 static int selinux_task_movememory(struct task_struct *p)
3589 {
3590         return current_has_perm(p, PROCESS__SETSCHED);
3591 }
3592
3593 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3594                                 int sig, u32 secid)
3595 {
3596         u32 perm;
3597         int rc;
3598
3599         if (!sig)
3600                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3601         else
3602                 perm = signal_to_av(sig);
3603         if (secid)
3604                 rc = avc_has_perm(secid, task_sid(p),
3605                                   SECCLASS_PROCESS, perm, NULL);
3606         else
3607                 rc = current_has_perm(p, perm);
3608         return rc;
3609 }
3610
3611 static int selinux_task_wait(struct task_struct *p)
3612 {
3613         return task_has_perm(p, current, PROCESS__SIGCHLD);
3614 }
3615
3616 static void selinux_task_to_inode(struct task_struct *p,
3617                                   struct inode *inode)
3618 {
3619         struct inode_security_struct *isec = inode->i_security;
3620         u32 sid = task_sid(p);
3621
3622         isec->sid = sid;
3623         isec->initialized = 1;
3624 }
3625
3626 /* Returns error only if unable to parse addresses */
3627 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3628                         struct common_audit_data *ad, u8 *proto)
3629 {
3630         int offset, ihlen, ret = -EINVAL;
3631         struct iphdr _iph, *ih;
3632
3633         offset = skb_network_offset(skb);
3634         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3635         if (ih == NULL)
3636                 goto out;
3637
3638         ihlen = ih->ihl * 4;
3639         if (ihlen < sizeof(_iph))
3640                 goto out;
3641
3642         ad->u.net->v4info.saddr = ih->saddr;
3643         ad->u.net->v4info.daddr = ih->daddr;
3644         ret = 0;
3645
3646         if (proto)
3647                 *proto = ih->protocol;
3648
3649         switch (ih->protocol) {
3650         case IPPROTO_TCP: {
3651                 struct tcphdr _tcph, *th;
3652
3653                 if (ntohs(ih->frag_off) & IP_OFFSET)
3654                         break;
3655
3656                 offset += ihlen;
3657                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3658                 if (th == NULL)
3659                         break;
3660
3661                 ad->u.net->sport = th->source;
3662                 ad->u.net->dport = th->dest;
3663                 break;
3664         }
3665
3666         case IPPROTO_UDP: {
3667                 struct udphdr _udph, *uh;
3668
3669                 if (ntohs(ih->frag_off) & IP_OFFSET)
3670                         break;
3671
3672                 offset += ihlen;
3673                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3674                 if (uh == NULL)
3675                         break;
3676
3677                 ad->u.net->sport = uh->source;
3678                 ad->u.net->dport = uh->dest;
3679                 break;
3680         }
3681
3682         case IPPROTO_DCCP: {
3683                 struct dccp_hdr _dccph, *dh;
3684
3685                 if (ntohs(ih->frag_off) & IP_OFFSET)
3686                         break;
3687
3688                 offset += ihlen;
3689                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3690                 if (dh == NULL)
3691                         break;
3692
3693                 ad->u.net->sport = dh->dccph_sport;
3694                 ad->u.net->dport = dh->dccph_dport;
3695                 break;
3696         }
3697
3698         default:
3699                 break;
3700         }
3701 out:
3702         return ret;
3703 }
3704
3705 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3706
3707 /* Returns error only if unable to parse addresses */
3708 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3709                         struct common_audit_data *ad, u8 *proto)
3710 {
3711         u8 nexthdr;
3712         int ret = -EINVAL, offset;
3713         struct ipv6hdr _ipv6h, *ip6;
3714         __be16 frag_off;
3715
3716         offset = skb_network_offset(skb);
3717         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3718         if (ip6 == NULL)
3719                 goto out;
3720
3721         ad->u.net->v6info.saddr = ip6->saddr;
3722         ad->u.net->v6info.daddr = ip6->daddr;
3723         ret = 0;
3724
3725         nexthdr = ip6->nexthdr;
3726         offset += sizeof(_ipv6h);
3727         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3728         if (offset < 0)
3729                 goto out;
3730
3731         if (proto)
3732                 *proto = nexthdr;
3733
3734         switch (nexthdr) {
3735         case IPPROTO_TCP: {
3736                 struct tcphdr _tcph, *th;
3737
3738                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3739                 if (th == NULL)
3740                         break;
3741
3742                 ad->u.net->sport = th->source;
3743                 ad->u.net->dport = th->dest;
3744                 break;
3745         }
3746
3747         case IPPROTO_UDP: {
3748                 struct udphdr _udph, *uh;
3749
3750                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3751                 if (uh == NULL)
3752                         break;
3753
3754                 ad->u.net->sport = uh->source;
3755                 ad->u.net->dport = uh->dest;
3756                 break;
3757         }
3758
3759         case IPPROTO_DCCP: {
3760                 struct dccp_hdr _dccph, *dh;
3761
3762                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3763                 if (dh == NULL)
3764                         break;
3765
3766                 ad->u.net->sport = dh->dccph_sport;
3767                 ad->u.net->dport = dh->dccph_dport;
3768                 break;
3769         }
3770
3771         /* includes fragments */
3772         default:
3773                 break;
3774         }
3775 out:
3776         return ret;
3777 }
3778
3779 #endif /* IPV6 */
3780
3781 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3782                              char **_addrp, int src, u8 *proto)
3783 {
3784         char *addrp;
3785         int ret;
3786
3787         switch (ad->u.net->family) {
3788         case PF_INET:
3789                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3790                 if (ret)
3791                         goto parse_error;
3792                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
3793                                        &ad->u.net->v4info.daddr);
3794                 goto okay;
3795
3796 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3797         case PF_INET6:
3798                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3799                 if (ret)
3800                         goto parse_error;
3801                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
3802                                        &ad->u.net->v6info.daddr);
3803                 goto okay;
3804 #endif  /* IPV6 */
3805         default:
3806                 addrp = NULL;
3807                 goto okay;
3808         }
3809
3810 parse_error:
3811         printk(KERN_WARNING
3812                "SELinux: failure in selinux_parse_skb(),"
3813                " unable to parse packet\n");
3814         return ret;
3815
3816 okay:
3817         if (_addrp)
3818                 *_addrp = addrp;
3819         return 0;
3820 }
3821
3822 /**
3823  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3824  * @skb: the packet
3825  * @family: protocol family
3826  * @sid: the packet's peer label SID
3827  *
3828  * Description:
3829  * Check the various different forms of network peer labeling and determine
3830  * the peer label/SID for the packet; most of the magic actually occurs in
3831  * the security server function security_net_peersid_cmp().  The function
3832  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3833  * or -EACCES if @sid is invalid due to inconsistencies with the different
3834  * peer labels.
3835  *
3836  */
3837 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3838 {
3839         int err;
3840         u32 xfrm_sid;
3841         u32 nlbl_sid;
3842         u32 nlbl_type;
3843
3844         err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
3845         if (unlikely(err))
3846                 return -EACCES;
3847         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3848         if (unlikely(err))
3849                 return -EACCES;
3850
3851         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3852         if (unlikely(err)) {
3853                 printk(KERN_WARNING
3854                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3855                        " unable to determine packet's peer label\n");
3856                 return -EACCES;
3857         }
3858
3859         return 0;
3860 }
3861
3862 /**
3863  * selinux_conn_sid - Determine the child socket label for a connection
3864  * @sk_sid: the parent socket's SID
3865  * @skb_sid: the packet's SID
3866  * @conn_sid: the resulting connection SID
3867  *
3868  * If @skb_sid is valid then the user:role:type information from @sk_sid is
3869  * combined with the MLS information from @skb_sid in order to create
3870  * @conn_sid.  If @skb_sid is not valid then then @conn_sid is simply a copy
3871  * of @sk_sid.  Returns zero on success, negative values on failure.
3872  *
3873  */
3874 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
3875 {
3876         int err = 0;
3877
3878         if (skb_sid != SECSID_NULL)
3879                 err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid);
3880         else
3881                 *conn_sid = sk_sid;
3882
3883         return err;
3884 }
3885
3886 /* socket security operations */
3887
3888 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3889                                  u16 secclass, u32 *socksid)
3890 {
3891         if (tsec->sockcreate_sid > SECSID_NULL) {
3892                 *socksid = tsec->sockcreate_sid;
3893                 return 0;
3894         }
3895
3896         return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3897                                        socksid);
3898 }
3899
3900 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3901 {
3902         struct sk_security_struct *sksec = sk->sk_security;
3903         struct common_audit_data ad;
3904         struct lsm_network_audit net = {0,};
3905         u32 tsid = task_sid(task);
3906
3907         if (sksec->sid == SECINITSID_KERNEL)
3908                 return 0;
3909
3910         ad.type = LSM_AUDIT_DATA_NET;
3911         ad.u.net = &net;
3912         ad.u.net->sk = sk;
3913
3914         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3915 }
3916
3917 static int selinux_socket_create(int family, int type,
3918                                  int protocol, int kern)
3919 {
3920         const struct task_security_struct *tsec = current_security();
3921         u32 newsid;
3922         u16 secclass;
3923         int rc;
3924
3925         if (kern)
3926                 return 0;
3927
3928         secclass = socket_type_to_security_class(family, type, protocol);
3929         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3930         if (rc)
3931                 return rc;
3932
3933         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3934 }
3935
3936 static int selinux_socket_post_create(struct socket *sock, int family,
3937                                       int type, int protocol, int kern)
3938 {
3939         const struct task_security_struct *tsec = current_security();
3940         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3941         struct sk_security_struct *sksec;
3942         int err = 0;
3943
3944         isec->sclass = socket_type_to_security_class(family, type, protocol);
3945
3946         if (kern)
3947                 isec->sid = SECINITSID_KERNEL;
3948         else {
3949                 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3950                 if (err)
3951                         return err;
3952         }
3953
3954         isec->initialized = 1;
3955
3956         if (sock->sk) {
3957                 sksec = sock->sk->sk_security;
3958                 sksec->sid = isec->sid;
3959                 sksec->sclass = isec->sclass;
3960                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3961         }
3962
3963         return err;
3964 }
3965
3966 /* Range of port numbers used to automatically bind.
3967    Need to determine whether we should perform a name_bind
3968    permission check between the socket and the port number. */
3969
3970 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3971 {
3972         struct sock *sk = sock->sk;
3973         u16 family;
3974         int err;
3975
3976         err = sock_has_perm(current, sk, SOCKET__BIND);
3977         if (err)
3978                 goto out;
3979
3980         /*
3981          * If PF_INET or PF_INET6, check name_bind permission for the port.
3982          * Multiple address binding for SCTP is not supported yet: we just
3983          * check the first address now.
3984          */
3985         family = sk->sk_family;
3986         if (family == PF_INET || family == PF_INET6) {
3987                 char *addrp;
3988                 struct sk_security_struct *sksec = sk->sk_security;
3989                 struct common_audit_data ad;
3990                 struct lsm_network_audit net = {0,};
3991                 struct sockaddr_in *addr4 = NULL;
3992                 struct sockaddr_in6 *addr6 = NULL;
3993                 unsigned short snum;
3994                 u32 sid, node_perm;
3995
3996                 if (family == PF_INET) {
3997                         addr4 = (struct sockaddr_in *)address;
3998                         snum = ntohs(addr4->sin_port);
3999                         addrp = (char *)&addr4->sin_addr.s_addr;
4000                 } else {
4001                         addr6 = (struct sockaddr_in6 *)address;
4002                         snum = ntohs(addr6->sin6_port);
4003                         addrp = (char *)&addr6->sin6_addr.s6_addr;
4004                 }
4005
4006                 if (snum) {
4007                         int low, high;
4008
4009                         inet_get_local_port_range(sock_net(sk), &low, &high);
4010
4011                         if (snum < max(PROT_SOCK, low) || snum > high) {
4012                                 err = sel_netport_sid(sk->sk_protocol,
4013                                                       snum, &sid);
4014                                 if (err)
4015                                         goto out;
4016                                 ad.type = LSM_AUDIT_DATA_NET;
4017                                 ad.u.net = &net;
4018                                 ad.u.net->sport = htons(snum);
4019                                 ad.u.net->family = family;
4020                                 err = avc_has_perm(sksec->sid, sid,
4021                                                    sksec->sclass,
4022                                                    SOCKET__NAME_BIND, &ad);
4023                                 if (err)
4024                                         goto out;
4025                         }
4026                 }
4027
4028                 switch (sksec->sclass) {
4029                 case SECCLASS_TCP_SOCKET:
4030                         node_perm = TCP_SOCKET__NODE_BIND;
4031                         break;
4032
4033                 case SECCLASS_UDP_SOCKET:
4034                         node_perm = UDP_SOCKET__NODE_BIND;
4035                         break;
4036
4037                 case SECCLASS_DCCP_SOCKET:
4038                         node_perm = DCCP_SOCKET__NODE_BIND;
4039                         break;
4040
4041                 default:
4042                         node_perm = RAWIP_SOCKET__NODE_BIND;
4043                         break;
4044                 }
4045
4046                 err = sel_netnode_sid(addrp, family, &sid);
4047                 if (err)
4048                         goto out;
4049
4050                 ad.type = LSM_AUDIT_DATA_NET;
4051                 ad.u.net = &net;
4052                 ad.u.net->sport = htons(snum);
4053                 ad.u.net->family = family;
4054
4055                 if (family == PF_INET)
4056                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4057                 else
4058                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4059
4060                 err = avc_has_perm(sksec->sid, sid,
4061                                    sksec->sclass, node_perm, &ad);
4062                 if (err)
4063                         goto out;
4064         }
4065 out:
4066         return err;
4067 }
4068
4069 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
4070 {
4071         struct sock *sk = sock->sk;
4072         struct sk_security_struct *sksec = sk->sk_security;
4073         int err;
4074
4075         err = sock_has_perm(current, sk, SOCKET__CONNECT);
4076         if (err)
4077                 return err;
4078
4079         /*
4080          * If a TCP or DCCP socket, check name_connect permission for the port.
4081          */
4082         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4083             sksec->sclass == SECCLASS_DCCP_SOCKET) {
4084                 struct common_audit_data ad;
4085                 struct lsm_network_audit net = {0,};
4086                 struct sockaddr_in *addr4 = NULL;
4087                 struct sockaddr_in6 *addr6 = NULL;
4088                 unsigned short snum;
4089                 u32 sid, perm;
4090
4091                 if (sk->sk_family == PF_INET) {
4092                         addr4 = (struct sockaddr_in *)address;
4093                         if (addrlen < sizeof(struct sockaddr_in))
4094                                 return -EINVAL;
4095                         snum = ntohs(addr4->sin_port);
4096                 } else {
4097                         addr6 = (struct sockaddr_in6 *)address;
4098                         if (addrlen < SIN6_LEN_RFC2133)
4099                                 return -EINVAL;
4100                         snum = ntohs(addr6->sin6_port);
4101                 }
4102
4103                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4104                 if (err)
4105                         goto out;
4106
4107                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
4108                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
4109
4110                 ad.type = LSM_AUDIT_DATA_NET;
4111                 ad.u.net = &net;
4112                 ad.u.net->dport = htons(snum);
4113                 ad.u.net->family = sk->sk_family;
4114                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4115                 if (err)
4116                         goto out;
4117         }
4118
4119         err = selinux_netlbl_socket_connect(sk, address);
4120
4121 out:
4122         return err;
4123 }
4124
4125 static int selinux_socket_listen(struct socket *sock, int backlog)
4126 {
4127         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
4128 }
4129
4130 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4131 {
4132         int err;
4133         struct inode_security_struct *isec;
4134         struct inode_security_struct *newisec;
4135
4136         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4137         if (err)
4138                 return err;
4139
4140         newisec = SOCK_INODE(newsock)->i_security;
4141
4142         isec = SOCK_INODE(sock)->i_security;
4143         newisec->sclass = isec->sclass;
4144         newisec->sid = isec->sid;
4145         newisec->initialized = 1;
4146
4147         return 0;
4148 }
4149
4150 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4151                                   int size)
4152 {
4153         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4154 }
4155
4156 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4157                                   int size, int flags)
4158 {
4159         return sock_has_perm(current, sock->sk, SOCKET__READ);
4160 }
4161
4162 static int selinux_socket_getsockname(struct socket *sock)
4163 {
4164         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4165 }
4166
4167 static int selinux_socket_getpeername(struct socket *sock)
4168 {
4169         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4170 }
4171
4172 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4173 {
4174         int err;
4175
4176         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4177         if (err)
4178                 return err;
4179
4180         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4181 }
4182
4183 static int selinux_socket_getsockopt(struct socket *sock, int level,
4184                                      int optname)
4185 {
4186         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4187 }
4188
4189 static int selinux_socket_shutdown(struct socket *sock, int how)
4190 {
4191         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4192 }
4193
4194 static int selinux_socket_unix_stream_connect(struct sock *sock,
4195                                               struct sock *other,
4196                                               struct sock *newsk)
4197 {
4198         struct sk_security_struct *sksec_sock = sock->sk_security;
4199         struct sk_security_struct *sksec_other = other->sk_security;
4200         struct sk_security_struct *sksec_new = newsk->sk_security;
4201         struct common_audit_data ad;
4202         struct lsm_network_audit net = {0,};
4203         int err;
4204
4205         ad.type = LSM_AUDIT_DATA_NET;
4206         ad.u.net = &net;
4207         ad.u.net->sk = other;
4208
4209         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4210                            sksec_other->sclass,
4211                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4212         if (err)
4213                 return err;
4214
4215         /* server child socket */
4216         sksec_new->peer_sid = sksec_sock->sid;
4217         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4218                                     &sksec_new->sid);
4219         if (err)
4220                 return err;
4221
4222         /* connecting socket */
4223         sksec_sock->peer_sid = sksec_new->sid;
4224
4225         return 0;
4226 }
4227
4228 static int selinux_socket_unix_may_send(struct socket *sock,
4229                                         struct socket *other)
4230 {
4231         struct sk_security_struct *ssec = sock->sk->sk_security;
4232         struct sk_security_struct *osec = other->sk->sk_security;
4233         struct common_audit_data ad;
4234         struct lsm_network_audit net = {0,};
4235
4236         ad.type = LSM_AUDIT_DATA_NET;
4237         ad.u.net = &net;
4238         ad.u.net->sk = other->sk;
4239
4240         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4241                             &ad);
4242 }
4243
4244 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4245                                     u32 peer_sid,
4246                                     struct common_audit_data *ad)
4247 {
4248         int err;
4249         u32 if_sid;
4250         u32 node_sid;
4251
4252         err = sel_netif_sid(ifindex, &if_sid);
4253         if (err)
4254                 return err;
4255         err = avc_has_perm(peer_sid, if_sid,
4256                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4257         if (err)
4258                 return err;
4259
4260         err = sel_netnode_sid(addrp, family, &node_sid);
4261         if (err)
4262                 return err;
4263         return avc_has_perm(peer_sid, node_sid,
4264                             SECCLASS_NODE, NODE__RECVFROM, ad);
4265 }
4266
4267 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4268                                        u16 family)
4269 {
4270         int err = 0;
4271         struct sk_security_struct *sksec = sk->sk_security;
4272         u32 sk_sid = sksec->sid;
4273         struct common_audit_data ad;
4274         struct lsm_network_audit net = {0,};
4275         char *addrp;
4276
4277         ad.type = LSM_AUDIT_DATA_NET;
4278         ad.u.net = &net;
4279         ad.u.net->netif = skb->skb_iif;
4280         ad.u.net->family = family;
4281         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4282         if (err)
4283                 return err;
4284
4285         if (selinux_secmark_enabled()) {
4286                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4287                                    PACKET__RECV, &ad);
4288                 if (err)
4289                         return err;
4290         }
4291
4292         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4293         if (err)
4294                 return err;
4295         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4296
4297         return err;
4298 }
4299
4300 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4301 {
4302         int err;
4303         struct sk_security_struct *sksec = sk->sk_security;
4304         u16 family = sk->sk_family;
4305         u32 sk_sid = sksec->sid;
4306         struct common_audit_data ad;
4307         struct lsm_network_audit net = {0,};
4308         char *addrp;
4309         u8 secmark_active;
4310         u8 peerlbl_active;
4311
4312         if (family != PF_INET && family != PF_INET6)
4313                 return 0;
4314
4315         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4316         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4317                 family = PF_INET;
4318
4319         /* If any sort of compatibility mode is enabled then handoff processing
4320          * to the selinux_sock_rcv_skb_compat() function to deal with the
4321          * special handling.  We do this in an attempt to keep this function
4322          * as fast and as clean as possible. */
4323         if (!selinux_policycap_netpeer)
4324                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4325
4326         secmark_active = selinux_secmark_enabled();
4327         peerlbl_active = selinux_peerlbl_enabled();
4328         if (!secmark_active && !peerlbl_active)
4329                 return 0;
4330
4331         ad.type = LSM_AUDIT_DATA_NET;
4332         ad.u.net = &net;
4333         ad.u.net->netif = skb->skb_iif;
4334         ad.u.net->family = family;
4335         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4336         if (err)
4337                 return err;
4338
4339         if (peerlbl_active) {
4340                 u32 peer_sid;
4341
4342                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4343                 if (err)
4344                         return err;
4345                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4346                                                peer_sid, &ad);
4347                 if (err) {
4348                         selinux_netlbl_err(skb, err, 0);
4349                         return err;
4350                 }
4351                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4352                                    PEER__RECV, &ad);
4353                 if (err) {
4354                         selinux_netlbl_err(skb, err, 0);
4355                         return err;
4356                 }
4357         }
4358
4359         if (secmark_active) {
4360                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4361                                    PACKET__RECV, &ad);
4362                 if (err)
4363                         return err;
4364         }
4365
4366         return err;
4367 }
4368
4369 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4370                                             int __user *optlen, unsigned len)
4371 {
4372         int err = 0;
4373         char *scontext;
4374         u32 scontext_len;
4375         struct sk_security_struct *sksec = sock->sk->sk_security;
4376         u32 peer_sid = SECSID_NULL;
4377
4378         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4379             sksec->sclass == SECCLASS_TCP_SOCKET)
4380                 peer_sid = sksec->peer_sid;
4381         if (peer_sid == SECSID_NULL)
4382                 return -ENOPROTOOPT;
4383
4384         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4385         if (err)
4386                 return err;
4387
4388         if (scontext_len > len) {
4389                 err = -ERANGE;
4390                 goto out_len;
4391         }
4392
4393         if (copy_to_user(optval, scontext, scontext_len))
4394                 err = -EFAULT;
4395
4396 out_len:
4397         if (put_user(scontext_len, optlen))
4398                 err = -EFAULT;
4399         kfree(scontext);
4400         return err;
4401 }
4402
4403 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4404 {
4405         u32 peer_secid = SECSID_NULL;
4406         u16 family;
4407
4408         if (skb && skb->protocol == htons(ETH_P_IP))
4409                 family = PF_INET;
4410         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4411                 family = PF_INET6;
4412         else if (sock)
4413                 family = sock->sk->sk_family;
4414         else
4415                 goto out;
4416
4417         if (sock && family == PF_UNIX)
4418                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4419         else if (skb)
4420                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4421
4422 out:
4423         *secid = peer_secid;
4424         if (peer_secid == SECSID_NULL)
4425                 return -EINVAL;
4426         return 0;
4427 }
4428
4429 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4430 {
4431         struct sk_security_struct *sksec;
4432
4433         sksec = kzalloc(sizeof(*sksec), priority);
4434         if (!sksec)
4435                 return -ENOMEM;
4436
4437         sksec->peer_sid = SECINITSID_UNLABELED;
4438         sksec->sid = SECINITSID_UNLABELED;
4439         selinux_netlbl_sk_security_reset(sksec);
4440         sk->sk_security = sksec;
4441
4442         return 0;
4443 }
4444
4445 static void selinux_sk_free_security(struct sock *sk)
4446 {
4447         struct sk_security_struct *sksec = sk->sk_security;
4448
4449         sk->sk_security = NULL;
4450         selinux_netlbl_sk_security_free(sksec);
4451         kfree(sksec);
4452 }
4453
4454 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4455 {
4456         struct sk_security_struct *sksec = sk->sk_security;
4457         struct sk_security_struct *newsksec = newsk->sk_security;
4458
4459         newsksec->sid = sksec->sid;
4460         newsksec->peer_sid = sksec->peer_sid;
4461         newsksec->sclass = sksec->sclass;
4462
4463         selinux_netlbl_sk_security_reset(newsksec);
4464 }
4465
4466 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4467 {
4468         if (!sk)
4469                 *secid = SECINITSID_ANY_SOCKET;
4470         else {
4471                 struct sk_security_struct *sksec = sk->sk_security;
4472
4473                 *secid = sksec->sid;
4474         }
4475 }
4476
4477 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4478 {
4479         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4480         struct sk_security_struct *sksec = sk->sk_security;
4481
4482         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4483             sk->sk_family == PF_UNIX)
4484                 isec->sid = sksec->sid;
4485         sksec->sclass = isec->sclass;
4486 }
4487
4488 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4489                                      struct request_sock *req)
4490 {
4491         struct sk_security_struct *sksec = sk->sk_security;
4492         int err;
4493         u16 family = req->rsk_ops->family;
4494         u32 connsid;
4495         u32 peersid;
4496
4497         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4498         if (err)
4499                 return err;
4500         err = selinux_conn_sid(sksec->sid, peersid, &connsid);
4501         if (err)
4502                 return err;
4503         req->secid = connsid;
4504         req->peer_secid = peersid;
4505
4506         return selinux_netlbl_inet_conn_request(req, family);
4507 }
4508
4509 static void selinux_inet_csk_clone(struct sock *newsk,
4510                                    const struct request_sock *req)
4511 {
4512         struct sk_security_struct *newsksec = newsk->sk_security;
4513
4514         newsksec->sid = req->secid;
4515         newsksec->peer_sid = req->peer_secid;
4516         /* NOTE: Ideally, we should also get the isec->sid for the
4517            new socket in sync, but we don't have the isec available yet.
4518            So we will wait until sock_graft to do it, by which
4519            time it will have been created and available. */
4520
4521         /* We don't need to take any sort of lock here as we are the only
4522          * thread with access to newsksec */
4523         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4524 }
4525
4526 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4527 {
4528         u16 family = sk->sk_family;
4529         struct sk_security_struct *sksec = sk->sk_security;
4530
4531         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4532         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4533                 family = PF_INET;
4534
4535         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4536 }
4537
4538 static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
4539 {
4540         skb_set_owner_w(skb, sk);
4541 }
4542
4543 static int selinux_secmark_relabel_packet(u32 sid)
4544 {
4545         const struct task_security_struct *__tsec;
4546         u32 tsid;
4547
4548         __tsec = current_security();
4549         tsid = __tsec->sid;
4550
4551         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4552 }
4553
4554 static void selinux_secmark_refcount_inc(void)
4555 {
4556         atomic_inc(&selinux_secmark_refcount);
4557 }
4558
4559 static void selinux_secmark_refcount_dec(void)
4560 {
4561         atomic_dec(&selinux_secmark_refcount);
4562 }
4563
4564 static void selinux_req_classify_flow(const struct request_sock *req,
4565                                       struct flowi *fl)
4566 {
4567         fl->flowi_secid = req->secid;
4568 }
4569
4570 static int selinux_tun_dev_alloc_security(void **security)
4571 {
4572         struct tun_security_struct *tunsec;
4573
4574         tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
4575         if (!tunsec)
4576                 return -ENOMEM;
4577         tunsec->sid = current_sid();
4578
4579         *security = tunsec;
4580         return 0;
4581 }
4582
4583 static void selinux_tun_dev_free_security(void *security)
4584 {
4585         kfree(security);
4586 }
4587
4588 static int selinux_tun_dev_create(void)
4589 {
4590         u32 sid = current_sid();
4591
4592         /* we aren't taking into account the "sockcreate" SID since the socket
4593          * that is being created here is not a socket in the traditional sense,
4594          * instead it is a private sock, accessible only to the kernel, and
4595          * representing a wide range of network traffic spanning multiple
4596          * connections unlike traditional sockets - check the TUN driver to
4597          * get a better understanding of why this socket is special */
4598
4599         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4600                             NULL);
4601 }
4602
4603 static int selinux_tun_dev_attach_queue(void *security)
4604 {
4605         struct tun_security_struct *tunsec = security;
4606
4607         return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
4608                             TUN_SOCKET__ATTACH_QUEUE, NULL);
4609 }
4610
4611 static int selinux_tun_dev_attach(struct sock *sk, void *security)
4612 {
4613         struct tun_security_struct *tunsec = security;
4614         struct sk_security_struct *sksec = sk->sk_security;
4615
4616         /* we don't currently perform any NetLabel based labeling here and it
4617          * isn't clear that we would want to do so anyway; while we could apply
4618          * labeling without the support of the TUN user the resulting labeled
4619          * traffic from the other end of the connection would almost certainly
4620          * cause confusion to the TUN user that had no idea network labeling
4621          * protocols were being used */
4622
4623         sksec->sid = tunsec->sid;
4624         sksec->sclass = SECCLASS_TUN_SOCKET;
4625
4626         return 0;
4627 }
4628
4629 static int selinux_tun_dev_open(void *security)
4630 {
4631         struct tun_security_struct *tunsec = security;
4632         u32 sid = current_sid();
4633         int err;
4634
4635         err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4636                            TUN_SOCKET__RELABELFROM, NULL);
4637         if (err)
4638                 return err;
4639         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4640                            TUN_SOCKET__RELABELTO, NULL);
4641         if (err)
4642                 return err;
4643         tunsec->sid = sid;
4644
4645         return 0;
4646 }
4647
4648 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4649 {
4650         int err = 0;
4651         u32 perm;
4652         struct nlmsghdr *nlh;
4653         struct sk_security_struct *sksec = sk->sk_security;
4654
4655         if (skb->len < NLMSG_HDRLEN) {
4656                 err = -EINVAL;
4657                 goto out;
4658         }
4659         nlh = nlmsg_hdr(skb);
4660
4661         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4662         if (err) {
4663                 if (err == -EINVAL) {
4664                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4665                                   "SELinux:  unrecognized netlink message"
4666                                   " type=%hu for sclass=%hu\n",
4667                                   nlh->nlmsg_type, sksec->sclass);
4668                         if (!selinux_enforcing || security_get_allow_unknown())
4669                                 err = 0;
4670                 }
4671
4672                 /* Ignore */
4673                 if (err == -ENOENT)
4674                         err = 0;
4675                 goto out;
4676         }
4677
4678         err = sock_has_perm(current, sk, perm);
4679 out:
4680         return err;
4681 }
4682
4683 #ifdef CONFIG_NETFILTER
4684
4685 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4686                                        u16 family)
4687 {
4688         int err;
4689         char *addrp;
4690         u32 peer_sid;
4691         struct common_audit_data ad;
4692         struct lsm_network_audit net = {0,};
4693         u8 secmark_active;
4694         u8 netlbl_active;
4695         u8 peerlbl_active;
4696
4697         if (!selinux_policycap_netpeer)
4698                 return NF_ACCEPT;
4699
4700         secmark_active = selinux_secmark_enabled();
4701         netlbl_active = netlbl_enabled();
4702         peerlbl_active = selinux_peerlbl_enabled();
4703         if (!secmark_active && !peerlbl_active)
4704                 return NF_ACCEPT;
4705
4706         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4707                 return NF_DROP;
4708
4709         ad.type = LSM_AUDIT_DATA_NET;
4710         ad.u.net = &net;
4711         ad.u.net->netif = ifindex;
4712         ad.u.net->family = family;
4713         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4714                 return NF_DROP;
4715
4716         if (peerlbl_active) {
4717                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4718                                                peer_sid, &ad);
4719                 if (err) {
4720                         selinux_netlbl_err(skb, err, 1);
4721                         return NF_DROP;
4722                 }
4723         }
4724
4725         if (secmark_active)
4726                 if (avc_has_perm(peer_sid, skb->secmark,
4727                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4728                         return NF_DROP;
4729
4730         if (netlbl_active)
4731                 /* we do this in the FORWARD path and not the POST_ROUTING
4732                  * path because we want to make sure we apply the necessary
4733                  * labeling before IPsec is applied so we can leverage AH
4734                  * protection */
4735                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4736                         return NF_DROP;
4737
4738         return NF_ACCEPT;
4739 }
4740
4741 static unsigned int selinux_ipv4_forward(const struct nf_hook_ops *ops,
4742                                          struct sk_buff *skb,
4743                                          const struct net_device *in,
4744                                          const struct net_device *out,
4745                                          int (*okfn)(struct sk_buff *))
4746 {
4747         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4748 }
4749
4750 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4751 static unsigned int selinux_ipv6_forward(const struct nf_hook_ops *ops,
4752                                          struct sk_buff *skb,
4753                                          const struct net_device *in,
4754                                          const struct net_device *out,
4755                                          int (*okfn)(struct sk_buff *))
4756 {
4757         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4758 }
4759 #endif  /* IPV6 */
4760
4761 static unsigned int selinux_ip_output(struct sk_buff *skb,
4762                                       u16 family)
4763 {
4764         struct sock *sk;
4765         u32 sid;
4766
4767         if (!netlbl_enabled())
4768                 return NF_ACCEPT;
4769
4770         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4771          * because we want to make sure we apply the necessary labeling
4772          * before IPsec is applied so we can leverage AH protection */
4773         sk = skb->sk;
4774         if (sk) {
4775                 struct sk_security_struct *sksec;
4776
4777                 if (sk->sk_state == TCP_LISTEN)
4778                         /* if the socket is the listening state then this
4779                          * packet is a SYN-ACK packet which means it needs to
4780                          * be labeled based on the connection/request_sock and
4781                          * not the parent socket.  unfortunately, we can't
4782                          * lookup the request_sock yet as it isn't queued on
4783                          * the parent socket until after the SYN-ACK is sent.
4784                          * the "solution" is to simply pass the packet as-is
4785                          * as any IP option based labeling should be copied
4786                          * from the initial connection request (in the IP
4787                          * layer).  it is far from ideal, but until we get a
4788                          * security label in the packet itself this is the
4789                          * best we can do. */
4790                         return NF_ACCEPT;
4791
4792                 /* standard practice, label using the parent socket */
4793                 sksec = sk->sk_security;
4794                 sid = sksec->sid;
4795         } else
4796                 sid = SECINITSID_KERNEL;
4797         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4798                 return NF_DROP;
4799
4800         return NF_ACCEPT;
4801 }
4802
4803 static unsigned int selinux_ipv4_output(const struct nf_hook_ops *ops,
4804                                         struct sk_buff *skb,
4805                                         const struct net_device *in,
4806                                         const struct net_device *out,
4807                                         int (*okfn)(struct sk_buff *))
4808 {
4809         return selinux_ip_output(skb, PF_INET);
4810 }
4811
4812 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4813                                                 int ifindex,
4814                                                 u16 family)
4815 {
4816         struct sock *sk = skb->sk;
4817         struct sk_security_struct *sksec;
4818         struct common_audit_data ad;
4819         struct lsm_network_audit net = {0,};
4820         char *addrp;
4821         u8 proto;
4822
4823         if (sk == NULL)
4824                 return NF_ACCEPT;
4825         sksec = sk->sk_security;
4826
4827         ad.type = LSM_AUDIT_DATA_NET;
4828         ad.u.net = &net;
4829         ad.u.net->netif = ifindex;
4830         ad.u.net->family = family;
4831         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4832                 return NF_DROP;
4833
4834         if (selinux_secmark_enabled())
4835                 if (avc_has_perm(sksec->sid, skb->secmark,
4836                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4837                         return NF_DROP_ERR(-ECONNREFUSED);
4838
4839         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4840                 return NF_DROP_ERR(-ECONNREFUSED);
4841
4842         return NF_ACCEPT;
4843 }
4844
4845 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4846                                          u16 family)
4847 {
4848         u32 secmark_perm;
4849         u32 peer_sid;
4850         struct sock *sk;
4851         struct common_audit_data ad;
4852         struct lsm_network_audit net = {0,};
4853         char *addrp;
4854         u8 secmark_active;
4855         u8 peerlbl_active;
4856
4857         /* If any sort of compatibility mode is enabled then handoff processing
4858          * to the selinux_ip_postroute_compat() function to deal with the
4859          * special handling.  We do this in an attempt to keep this function
4860          * as fast and as clean as possible. */
4861         if (!selinux_policycap_netpeer)
4862                 return selinux_ip_postroute_compat(skb, ifindex, family);
4863
4864         secmark_active = selinux_secmark_enabled();
4865         peerlbl_active = selinux_peerlbl_enabled();
4866         if (!secmark_active && !peerlbl_active)
4867                 return NF_ACCEPT;
4868
4869         sk = skb->sk;
4870
4871 #ifdef CONFIG_XFRM
4872         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4873          * packet transformation so allow the packet to pass without any checks
4874          * since we'll have another chance to perform access control checks
4875          * when the packet is on it's final way out.
4876          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4877          *       is NULL, in this case go ahead and apply access control.
4878          * NOTE: if this is a local socket (skb->sk != NULL) that is in the
4879          *       TCP listening state we cannot wait until the XFRM processing
4880          *       is done as we will miss out on the SA label if we do;
4881          *       unfortunately, this means more work, but it is only once per
4882          *       connection. */
4883         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
4884             !(sk != NULL && sk->sk_state == TCP_LISTEN))
4885                 return NF_ACCEPT;
4886 #endif
4887
4888         if (sk == NULL) {
4889                 /* Without an associated socket the packet is either coming
4890                  * from the kernel or it is being forwarded; check the packet
4891                  * to determine which and if the packet is being forwarded
4892                  * query the packet directly to determine the security label. */
4893                 if (skb->skb_iif) {
4894                         secmark_perm = PACKET__FORWARD_OUT;
4895                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4896                                 return NF_DROP;
4897                 } else {
4898                         secmark_perm = PACKET__SEND;
4899                         peer_sid = SECINITSID_KERNEL;
4900                 }
4901         } else if (sk->sk_state == TCP_LISTEN) {
4902                 /* Locally generated packet but the associated socket is in the
4903                  * listening state which means this is a SYN-ACK packet.  In
4904                  * this particular case the correct security label is assigned
4905                  * to the connection/request_sock but unfortunately we can't
4906                  * query the request_sock as it isn't queued on the parent
4907                  * socket until after the SYN-ACK packet is sent; the only
4908                  * viable choice is to regenerate the label like we do in
4909                  * selinux_inet_conn_request().  See also selinux_ip_output()
4910                  * for similar problems. */
4911                 u32 skb_sid;
4912                 struct sk_security_struct *sksec = sk->sk_security;
4913                 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
4914                         return NF_DROP;
4915                 /* At this point, if the returned skb peerlbl is SECSID_NULL
4916                  * and the packet has been through at least one XFRM
4917                  * transformation then we must be dealing with the "final"
4918                  * form of labeled IPsec packet; since we've already applied
4919                  * all of our access controls on this packet we can safely
4920                  * pass the packet. */
4921                 if (skb_sid == SECSID_NULL) {
4922                         switch (family) {
4923                         case PF_INET:
4924                                 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
4925                                         return NF_ACCEPT;
4926                                 break;
4927                         case PF_INET6:
4928                                 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
4929                                         return NF_ACCEPT;
4930                         default:
4931                                 return NF_DROP_ERR(-ECONNREFUSED);
4932                         }
4933                 }
4934                 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
4935                         return NF_DROP;
4936                 secmark_perm = PACKET__SEND;
4937         } else {
4938                 /* Locally generated packet, fetch the security label from the
4939                  * associated socket. */
4940                 struct sk_security_struct *sksec = sk->sk_security;
4941                 peer_sid = sksec->sid;
4942                 secmark_perm = PACKET__SEND;
4943         }
4944
4945         ad.type = LSM_AUDIT_DATA_NET;
4946         ad.u.net = &net;
4947         ad.u.net->netif = ifindex;
4948         ad.u.net->family = family;
4949         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4950                 return NF_DROP;
4951
4952         if (secmark_active)
4953                 if (avc_has_perm(peer_sid, skb->secmark,
4954                                  SECCLASS_PACKET, secmark_perm, &ad))
4955                         return NF_DROP_ERR(-ECONNREFUSED);
4956
4957         if (peerlbl_active) {
4958                 u32 if_sid;
4959                 u32 node_sid;
4960
4961                 if (sel_netif_sid(ifindex, &if_sid))
4962                         return NF_DROP;
4963                 if (avc_has_perm(peer_sid, if_sid,
4964                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4965                         return NF_DROP_ERR(-ECONNREFUSED);
4966
4967                 if (sel_netnode_sid(addrp, family, &node_sid))
4968                         return NF_DROP;
4969                 if (avc_has_perm(peer_sid, node_sid,
4970                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4971                         return NF_DROP_ERR(-ECONNREFUSED);
4972         }
4973
4974         return NF_ACCEPT;
4975 }
4976
4977 static unsigned int selinux_ipv4_postroute(const struct nf_hook_ops *ops,
4978                                            struct sk_buff *skb,
4979                                            const struct net_device *in,
4980                                            const struct net_device *out,
4981                                            int (*okfn)(struct sk_buff *))
4982 {
4983         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4984 }
4985
4986 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4987 static unsigned int selinux_ipv6_postroute(const struct nf_hook_ops *ops,
4988                                            struct sk_buff *skb,
4989                                            const struct net_device *in,
4990                                            const struct net_device *out,
4991                                            int (*okfn)(struct sk_buff *))
4992 {
4993         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4994 }
4995 #endif  /* IPV6 */
4996
4997 #endif  /* CONFIG_NETFILTER */
4998
4999 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5000 {
5001         int err;
5002
5003         err = cap_netlink_send(sk, skb);
5004         if (err)
5005                 return err;
5006
5007         return selinux_nlmsg_perm(sk, skb);
5008 }
5009
5010 static int ipc_alloc_security(struct task_struct *task,
5011                               struct kern_ipc_perm *perm,
5012                               u16 sclass)
5013 {
5014         struct ipc_security_struct *isec;
5015         u32 sid;
5016
5017         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
5018         if (!isec)
5019                 return -ENOMEM;
5020
5021         sid = task_sid(task);
5022         isec->sclass = sclass;
5023         isec->sid = sid;
5024         perm->security = isec;
5025
5026         return 0;
5027 }
5028
5029 static void ipc_free_security(struct kern_ipc_perm *perm)
5030 {
5031         struct ipc_security_struct *isec = perm->security;
5032         perm->security = NULL;
5033         kfree(isec);
5034 }
5035
5036 static int msg_msg_alloc_security(struct msg_msg *msg)
5037 {
5038         struct msg_security_struct *msec;
5039
5040         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
5041         if (!msec)
5042                 return -ENOMEM;
5043
5044         msec->sid = SECINITSID_UNLABELED;
5045         msg->security = msec;
5046
5047         return 0;
5048 }
5049
5050 static void msg_msg_free_security(struct msg_msg *msg)
5051 {
5052         struct msg_security_struct *msec = msg->security;
5053
5054         msg->security = NULL;
5055         kfree(msec);
5056 }
5057
5058 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5059                         u32 perms)
5060 {
5061         struct ipc_security_struct *isec;
5062         struct common_audit_data ad;
5063         u32 sid = current_sid();
5064
5065         isec = ipc_perms->security;
5066
5067         ad.type = LSM_AUDIT_DATA_IPC;
5068         ad.u.ipc_id = ipc_perms->key;
5069
5070         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
5071 }
5072
5073 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5074 {
5075         return msg_msg_alloc_security(msg);
5076 }
5077
5078 static void selinux_msg_msg_free_security(struct msg_msg *msg)
5079 {
5080         msg_msg_free_security(msg);
5081 }
5082
5083 /* message queue security operations */
5084 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
5085 {
5086         struct ipc_security_struct *isec;
5087         struct common_audit_data ad;
5088         u32 sid = current_sid();
5089         int rc;
5090
5091         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
5092         if (rc)
5093                 return rc;
5094
5095         isec = msq->q_perm.security;
5096
5097         ad.type = LSM_AUDIT_DATA_IPC;
5098         ad.u.ipc_id = msq->q_perm.key;
5099
5100         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5101                           MSGQ__CREATE, &ad);
5102         if (rc) {
5103                 ipc_free_security(&msq->q_perm);
5104                 return rc;
5105         }
5106         return 0;
5107 }
5108
5109 static void selinux_msg_queue_free_security(struct msg_queue *msq)
5110 {
5111         ipc_free_security(&msq->q_perm);
5112 }
5113
5114 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
5115 {
5116         struct ipc_security_struct *isec;
5117         struct common_audit_data ad;
5118         u32 sid = current_sid();
5119
5120         isec = msq->q_perm.security;
5121
5122         ad.type = LSM_AUDIT_DATA_IPC;
5123         ad.u.ipc_id = msq->q_perm.key;
5124
5125         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5126                             MSGQ__ASSOCIATE, &ad);
5127 }
5128
5129 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
5130 {
5131         int err;
5132         int perms;
5133
5134         switch (cmd) {
5135         case IPC_INFO:
5136         case MSG_INFO:
5137                 /* No specific object, just general system-wide information. */
5138                 return task_has_system(current, SYSTEM__IPC_INFO);
5139         case IPC_STAT:
5140         case MSG_STAT:
5141                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5142                 break;
5143         case IPC_SET:
5144                 perms = MSGQ__SETATTR;
5145                 break;
5146         case IPC_RMID:
5147                 perms = MSGQ__DESTROY;
5148                 break;
5149         default:
5150                 return 0;
5151         }
5152
5153         err = ipc_has_perm(&msq->q_perm, perms);
5154         return err;
5155 }
5156
5157 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
5158 {
5159         struct ipc_security_struct *isec;
5160         struct msg_security_struct *msec;
5161         struct common_audit_data ad;
5162         u32 sid = current_sid();
5163         int rc;
5164
5165         isec = msq->q_perm.security;
5166         msec = msg->security;
5167
5168         /*
5169          * First time through, need to assign label to the message
5170          */
5171         if (msec->sid == SECINITSID_UNLABELED) {
5172                 /*
5173                  * Compute new sid based on current process and
5174                  * message queue this message will be stored in
5175                  */
5176                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5177                                              NULL, &msec->sid);
5178                 if (rc)
5179                         return rc;
5180         }
5181
5182         ad.type = LSM_AUDIT_DATA_IPC;
5183         ad.u.ipc_id = msq->q_perm.key;
5184
5185         /* Can this process write to the queue? */
5186         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5187                           MSGQ__WRITE, &ad);
5188         if (!rc)
5189                 /* Can this process send the message */
5190                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5191                                   MSG__SEND, &ad);
5192         if (!rc)
5193                 /* Can the message be put in the queue? */
5194                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5195                                   MSGQ__ENQUEUE, &ad);
5196
5197         return rc;
5198 }
5199
5200 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5201                                     struct task_struct *target,
5202                                     long type, int mode)
5203 {
5204         struct ipc_security_struct *isec;
5205         struct msg_security_struct *msec;
5206         struct common_audit_data ad;
5207         u32 sid = task_sid(target);
5208         int rc;
5209
5210         isec = msq->q_perm.security;
5211         msec = msg->security;
5212
5213         ad.type = LSM_AUDIT_DATA_IPC;
5214         ad.u.ipc_id = msq->q_perm.key;
5215
5216         rc = avc_has_perm(sid, isec->sid,
5217                           SECCLASS_MSGQ, MSGQ__READ, &ad);
5218         if (!rc)
5219                 rc = avc_has_perm(sid, msec->sid,
5220                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
5221         return rc;
5222 }
5223
5224 /* Shared Memory security operations */
5225 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5226 {
5227         struct ipc_security_struct *isec;
5228         struct common_audit_data ad;
5229         u32 sid = current_sid();
5230         int rc;
5231
5232         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5233         if (rc)
5234                 return rc;
5235
5236         isec = shp->shm_perm.security;
5237
5238         ad.type = LSM_AUDIT_DATA_IPC;
5239         ad.u.ipc_id = shp->shm_perm.key;
5240
5241         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5242                           SHM__CREATE, &ad);
5243         if (rc) {
5244                 ipc_free_security(&shp->shm_perm);
5245                 return rc;
5246         }
5247         return 0;
5248 }
5249
5250 static void selinux_shm_free_security(struct shmid_kernel *shp)
5251 {
5252         ipc_free_security(&shp->shm_perm);
5253 }
5254
5255 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5256 {
5257         struct ipc_security_struct *isec;
5258         struct common_audit_data ad;
5259         u32 sid = current_sid();
5260
5261         isec = shp->shm_perm.security;
5262
5263         ad.type = LSM_AUDIT_DATA_IPC;
5264         ad.u.ipc_id = shp->shm_perm.key;
5265
5266         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5267                             SHM__ASSOCIATE, &ad);
5268 }
5269
5270 /* Note, at this point, shp is locked down */
5271 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5272 {
5273         int perms;
5274         int err;
5275
5276         switch (cmd) {
5277         case IPC_INFO:
5278         case SHM_INFO:
5279                 /* No specific object, just general system-wide information. */
5280                 return task_has_system(current, SYSTEM__IPC_INFO);
5281         case IPC_STAT:
5282         case SHM_STAT:
5283                 perms = SHM__GETATTR | SHM__ASSOCIATE;
5284                 break;
5285         case IPC_SET:
5286                 perms = SHM__SETATTR;
5287                 break;
5288         case SHM_LOCK:
5289         case SHM_UNLOCK:
5290                 perms = SHM__LOCK;
5291                 break;
5292         case IPC_RMID:
5293                 perms = SHM__DESTROY;
5294                 break;
5295         default:
5296                 return 0;
5297         }
5298
5299         err = ipc_has_perm(&shp->shm_perm, perms);
5300         return err;
5301 }
5302
5303 static int selinux_shm_shmat(struct shmid_kernel *shp,
5304                              char __user *shmaddr, int shmflg)
5305 {
5306         u32 perms;
5307
5308         if (shmflg & SHM_RDONLY)
5309                 perms = SHM__READ;
5310         else
5311                 perms = SHM__READ | SHM__WRITE;
5312
5313         return ipc_has_perm(&shp->shm_perm, perms);
5314 }
5315
5316 /* Semaphore security operations */
5317 static int selinux_sem_alloc_security(struct sem_array *sma)
5318 {
5319         struct ipc_security_struct *isec;
5320         struct common_audit_data ad;
5321         u32 sid = current_sid();
5322         int rc;
5323
5324         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5325         if (rc)
5326                 return rc;
5327
5328         isec = sma->sem_perm.security;
5329
5330         ad.type = LSM_AUDIT_DATA_IPC;
5331         ad.u.ipc_id = sma->sem_perm.key;
5332
5333         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5334                           SEM__CREATE, &ad);
5335         if (rc) {
5336                 ipc_free_security(&sma->sem_perm);
5337                 return rc;
5338         }
5339         return 0;
5340 }
5341
5342 static void selinux_sem_free_security(struct sem_array *sma)
5343 {
5344         ipc_free_security(&sma->sem_perm);
5345 }
5346
5347 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5348 {
5349         struct ipc_security_struct *isec;
5350         struct common_audit_data ad;
5351         u32 sid = current_sid();
5352
5353         isec = sma->sem_perm.security;
5354
5355         ad.type = LSM_AUDIT_DATA_IPC;
5356         ad.u.ipc_id = sma->sem_perm.key;
5357
5358         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5359                             SEM__ASSOCIATE, &ad);
5360 }
5361
5362 /* Note, at this point, sma is locked down */
5363 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5364 {
5365         int err;
5366         u32 perms;
5367
5368         switch (cmd) {
5369         case IPC_INFO:
5370         case SEM_INFO:
5371                 /* No specific object, just general system-wide information. */
5372                 return task_has_system(current, SYSTEM__IPC_INFO);
5373         case GETPID:
5374         case GETNCNT:
5375         case GETZCNT:
5376                 perms = SEM__GETATTR;
5377                 break;
5378         case GETVAL:
5379         case GETALL:
5380                 perms = SEM__READ;
5381                 break;
5382         case SETVAL:
5383         case SETALL:
5384                 perms = SEM__WRITE;
5385                 break;
5386         case IPC_RMID:
5387                 perms = SEM__DESTROY;
5388                 break;
5389         case IPC_SET:
5390                 perms = SEM__SETATTR;
5391                 break;
5392         case IPC_STAT:
5393         case SEM_STAT:
5394                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5395                 break;
5396         default:
5397                 return 0;
5398         }
5399
5400         err = ipc_has_perm(&sma->sem_perm, perms);
5401         return err;
5402 }
5403
5404 static int selinux_sem_semop(struct sem_array *sma,
5405                              struct sembuf *sops, unsigned nsops, int alter)
5406 {
5407         u32 perms;
5408
5409         if (alter)
5410                 perms = SEM__READ | SEM__WRITE;
5411         else
5412                 perms = SEM__READ;
5413
5414         return ipc_has_perm(&sma->sem_perm, perms);
5415 }
5416
5417 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5418 {
5419         u32 av = 0;
5420
5421         av = 0;
5422         if (flag & S_IRUGO)
5423                 av |= IPC__UNIX_READ;
5424         if (flag & S_IWUGO)
5425                 av |= IPC__UNIX_WRITE;
5426
5427         if (av == 0)
5428                 return 0;
5429
5430         return ipc_has_perm(ipcp, av);
5431 }
5432
5433 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5434 {
5435         struct ipc_security_struct *isec = ipcp->security;
5436         *secid = isec->sid;
5437 }
5438
5439 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5440 {
5441         if (inode)
5442                 inode_doinit_with_dentry(inode, dentry);
5443 }
5444
5445 static int selinux_getprocattr(struct task_struct *p,
5446                                char *name, char **value)
5447 {
5448         const struct task_security_struct *__tsec;
5449         u32 sid;
5450         int error;
5451         unsigned len;
5452
5453         if (current != p) {
5454                 error = current_has_perm(p, PROCESS__GETATTR);
5455                 if (error)
5456                         return error;
5457         }
5458
5459         rcu_read_lock();
5460         __tsec = __task_cred(p)->security;
5461
5462         if (!strcmp(name, "current"))
5463                 sid = __tsec->sid;
5464         else if (!strcmp(name, "prev"))
5465                 sid = __tsec->osid;
5466         else if (!strcmp(name, "exec"))
5467                 sid = __tsec->exec_sid;
5468         else if (!strcmp(name, "fscreate"))
5469                 sid = __tsec->create_sid;
5470         else if (!strcmp(name, "keycreate"))
5471                 sid = __tsec->keycreate_sid;
5472         else if (!strcmp(name, "sockcreate"))
5473                 sid = __tsec->sockcreate_sid;
5474         else
5475                 goto invalid;
5476         rcu_read_unlock();
5477
5478         if (!sid)
5479                 return 0;
5480
5481         error = security_sid_to_context(sid, value, &len);
5482         if (error)
5483                 return error;
5484         return len;
5485
5486 invalid:
5487         rcu_read_unlock();
5488         return -EINVAL;
5489 }
5490
5491 static int selinux_setprocattr(struct task_struct *p,
5492                                char *name, void *value, size_t size)
5493 {
5494         struct task_security_struct *tsec;
5495         struct task_struct *tracer;
5496         struct cred *new;
5497         u32 sid = 0, ptsid;
5498         int error;
5499         char *str = value;
5500
5501         if (current != p) {
5502                 /* SELinux only allows a process to change its own
5503                    security attributes. */
5504                 return -EACCES;
5505         }
5506
5507         /*
5508          * Basic control over ability to set these attributes at all.
5509          * current == p, but we'll pass them separately in case the
5510          * above restriction is ever removed.
5511          */
5512         if (!strcmp(name, "exec"))
5513                 error = current_has_perm(p, PROCESS__SETEXEC);
5514         else if (!strcmp(name, "fscreate"))
5515                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5516         else if (!strcmp(name, "keycreate"))
5517                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5518         else if (!strcmp(name, "sockcreate"))
5519                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5520         else if (!strcmp(name, "current"))
5521                 error = current_has_perm(p, PROCESS__SETCURRENT);
5522         else
5523                 error = -EINVAL;
5524         if (error)
5525                 return error;
5526
5527         /* Obtain a SID for the context, if one was specified. */
5528         if (size && str[1] && str[1] != '\n') {
5529                 if (str[size-1] == '\n') {
5530                         str[size-1] = 0;
5531                         size--;
5532                 }
5533                 error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5534                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5535                         if (!capable(CAP_MAC_ADMIN)) {
5536                                 struct audit_buffer *ab;
5537                                 size_t audit_size;
5538
5539                                 /* We strip a nul only if it is at the end, otherwise the
5540                                  * context contains a nul and we should audit that */
5541                                 if (str[size - 1] == '\0')
5542                                         audit_size = size - 1;
5543                                 else
5544                                         audit_size = size;
5545                                 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5546                                 audit_log_format(ab, "op=fscreate invalid_context=");
5547                                 audit_log_n_untrustedstring(ab, value, audit_size);
5548                                 audit_log_end(ab);
5549
5550                                 return error;
5551                         }
5552                         error = security_context_to_sid_force(value, size,
5553                                                               &sid);
5554                 }
5555                 if (error)
5556                         return error;
5557         }
5558
5559         new = prepare_creds();
5560         if (!new)
5561                 return -ENOMEM;
5562
5563         /* Permission checking based on the specified context is
5564            performed during the actual operation (execve,
5565            open/mkdir/...), when we know the full context of the
5566            operation.  See selinux_bprm_set_creds for the execve
5567            checks and may_create for the file creation checks. The
5568            operation will then fail if the context is not permitted. */
5569         tsec = new->security;
5570         if (!strcmp(name, "exec")) {
5571                 tsec->exec_sid = sid;
5572         } else if (!strcmp(name, "fscreate")) {
5573                 tsec->create_sid = sid;
5574         } else if (!strcmp(name, "keycreate")) {
5575                 error = may_create_key(sid, p);
5576                 if (error)
5577                         goto abort_change;
5578                 tsec->keycreate_sid = sid;
5579         } else if (!strcmp(name, "sockcreate")) {
5580                 tsec->sockcreate_sid = sid;
5581         } else if (!strcmp(name, "current")) {
5582                 error = -EINVAL;
5583                 if (sid == 0)
5584                         goto abort_change;
5585
5586                 /* Only allow single threaded processes to change context */
5587                 error = -EPERM;
5588                 if (!current_is_single_threaded()) {
5589                         error = security_bounded_transition(tsec->sid, sid);
5590                         if (error)
5591                                 goto abort_change;
5592                 }
5593
5594                 /* Check permissions for the transition. */
5595                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5596                                      PROCESS__DYNTRANSITION, NULL);
5597                 if (error)
5598                         goto abort_change;
5599
5600                 /* Check for ptracing, and update the task SID if ok.
5601                    Otherwise, leave SID unchanged and fail. */
5602                 ptsid = 0;
5603                 rcu_read_lock();
5604                 tracer = ptrace_parent(p);
5605                 if (tracer)
5606                         ptsid = task_sid(tracer);
5607                 rcu_read_unlock();
5608
5609                 if (tracer) {
5610                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5611                                              PROCESS__PTRACE, NULL);
5612                         if (error)
5613                                 goto abort_change;
5614                 }
5615
5616                 tsec->sid = sid;
5617         } else {
5618                 error = -EINVAL;
5619                 goto abort_change;
5620         }
5621
5622         commit_creds(new);
5623         return size;
5624
5625 abort_change:
5626         abort_creds(new);
5627         return error;
5628 }
5629
5630 static int selinux_ismaclabel(const char *name)
5631 {
5632         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
5633 }
5634
5635 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5636 {
5637         return security_sid_to_context(secid, secdata, seclen);
5638 }
5639
5640 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5641 {
5642         return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
5643 }
5644
5645 static void selinux_release_secctx(char *secdata, u32 seclen)
5646 {
5647         kfree(secdata);
5648 }
5649
5650 /*
5651  *      called with inode->i_mutex locked
5652  */
5653 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5654 {
5655         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5656 }
5657
5658 /*
5659  *      called with inode->i_mutex locked
5660  */
5661 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5662 {
5663         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5664 }
5665
5666 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5667 {
5668         int len = 0;
5669         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5670                                                 ctx, true);
5671         if (len < 0)
5672                 return len;
5673         *ctxlen = len;
5674         return 0;
5675 }
5676 #ifdef CONFIG_KEYS
5677
5678 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5679                              unsigned long flags)
5680 {
5681         const struct task_security_struct *tsec;
5682         struct key_security_struct *ksec;
5683
5684         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5685         if (!ksec)
5686                 return -ENOMEM;
5687
5688         tsec = cred->security;
5689         if (tsec->keycreate_sid)
5690                 ksec->sid = tsec->keycreate_sid;
5691         else
5692                 ksec->sid = tsec->sid;
5693
5694         k->security = ksec;
5695         return 0;
5696 }
5697
5698 static void selinux_key_free(struct key *k)
5699 {
5700         struct key_security_struct *ksec = k->security;
5701
5702         k->security = NULL;
5703         kfree(ksec);
5704 }
5705
5706 static int selinux_key_permission(key_ref_t key_ref,
5707                                   const struct cred *cred,
5708                                   key_perm_t perm)
5709 {
5710         struct key *key;
5711         struct key_security_struct *ksec;
5712         u32 sid;
5713
5714         /* if no specific permissions are requested, we skip the
5715            permission check. No serious, additional covert channels
5716            appear to be created. */
5717         if (perm == 0)
5718                 return 0;
5719
5720         sid = cred_sid(cred);
5721
5722         key = key_ref_to_ptr(key_ref);
5723         ksec = key->security;
5724
5725         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5726 }
5727
5728 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5729 {
5730         struct key_security_struct *ksec = key->security;
5731         char *context = NULL;
5732         unsigned len;
5733         int rc;
5734
5735         rc = security_sid_to_context(ksec->sid, &context, &len);
5736         if (!rc)
5737                 rc = len;
5738         *_buffer = context;
5739         return rc;
5740 }
5741
5742 #endif
5743
5744 static struct security_operations selinux_ops = {
5745         .name =                         "selinux",
5746
5747         .ptrace_access_check =          selinux_ptrace_access_check,
5748         .ptrace_traceme =               selinux_ptrace_traceme,
5749         .capget =                       selinux_capget,
5750         .capset =                       selinux_capset,
5751         .capable =                      selinux_capable,
5752         .quotactl =                     selinux_quotactl,
5753         .quota_on =                     selinux_quota_on,
5754         .syslog =                       selinux_syslog,
5755         .vm_enough_memory =             selinux_vm_enough_memory,
5756
5757         .netlink_send =                 selinux_netlink_send,
5758
5759         .bprm_set_creds =               selinux_bprm_set_creds,
5760         .bprm_committing_creds =        selinux_bprm_committing_creds,
5761         .bprm_committed_creds =         selinux_bprm_committed_creds,
5762         .bprm_secureexec =              selinux_bprm_secureexec,
5763
5764         .sb_alloc_security =            selinux_sb_alloc_security,
5765         .sb_free_security =             selinux_sb_free_security,
5766         .sb_copy_data =                 selinux_sb_copy_data,
5767         .sb_remount =                   selinux_sb_remount,
5768         .sb_kern_mount =                selinux_sb_kern_mount,
5769         .sb_show_options =              selinux_sb_show_options,
5770         .sb_statfs =                    selinux_sb_statfs,
5771         .sb_mount =                     selinux_mount,
5772         .sb_umount =                    selinux_umount,
5773         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5774         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5775         .sb_parse_opts_str =            selinux_parse_opts_str,
5776
5777         .dentry_init_security =         selinux_dentry_init_security,
5778
5779         .inode_alloc_security =         selinux_inode_alloc_security,
5780         .inode_free_security =          selinux_inode_free_security,
5781         .inode_init_security =          selinux_inode_init_security,
5782         .inode_create =                 selinux_inode_create,
5783         .inode_link =                   selinux_inode_link,
5784         .inode_unlink =                 selinux_inode_unlink,
5785         .inode_symlink =                selinux_inode_symlink,
5786         .inode_mkdir =                  selinux_inode_mkdir,
5787         .inode_rmdir =                  selinux_inode_rmdir,
5788         .inode_mknod =                  selinux_inode_mknod,
5789         .inode_rename =                 selinux_inode_rename,
5790         .inode_readlink =               selinux_inode_readlink,
5791         .inode_follow_link =            selinux_inode_follow_link,
5792         .inode_permission =             selinux_inode_permission,
5793         .inode_setattr =                selinux_inode_setattr,
5794         .inode_getattr =                selinux_inode_getattr,
5795         .inode_setxattr =               selinux_inode_setxattr,
5796         .inode_post_setxattr =          selinux_inode_post_setxattr,
5797         .inode_getxattr =               selinux_inode_getxattr,
5798         .inode_listxattr =              selinux_inode_listxattr,
5799         .inode_removexattr =            selinux_inode_removexattr,
5800         .inode_getsecurity =            selinux_inode_getsecurity,
5801         .inode_setsecurity =            selinux_inode_setsecurity,
5802         .inode_listsecurity =           selinux_inode_listsecurity,
5803         .inode_getsecid =               selinux_inode_getsecid,
5804
5805         .file_permission =              selinux_file_permission,
5806         .file_alloc_security =          selinux_file_alloc_security,
5807         .file_free_security =           selinux_file_free_security,
5808         .file_ioctl =                   selinux_file_ioctl,
5809         .mmap_file =                    selinux_mmap_file,
5810         .mmap_addr =                    selinux_mmap_addr,
5811         .file_mprotect =                selinux_file_mprotect,
5812         .file_lock =                    selinux_file_lock,
5813         .file_fcntl =                   selinux_file_fcntl,
5814         .file_set_fowner =              selinux_file_set_fowner,
5815         .file_send_sigiotask =          selinux_file_send_sigiotask,
5816         .file_receive =                 selinux_file_receive,
5817
5818         .file_open =                    selinux_file_open,
5819
5820         .task_create =                  selinux_task_create,
5821         .cred_alloc_blank =             selinux_cred_alloc_blank,
5822         .cred_free =                    selinux_cred_free,
5823         .cred_prepare =                 selinux_cred_prepare,
5824         .cred_transfer =                selinux_cred_transfer,
5825         .kernel_act_as =                selinux_kernel_act_as,
5826         .kernel_create_files_as =       selinux_kernel_create_files_as,
5827         .kernel_module_request =        selinux_kernel_module_request,
5828         .task_setpgid =                 selinux_task_setpgid,
5829         .task_getpgid =                 selinux_task_getpgid,
5830         .task_getsid =                  selinux_task_getsid,
5831         .task_getsecid =                selinux_task_getsecid,
5832         .task_setnice =                 selinux_task_setnice,
5833         .task_setioprio =               selinux_task_setioprio,
5834         .task_getioprio =               selinux_task_getioprio,
5835         .task_setrlimit =               selinux_task_setrlimit,
5836         .task_setscheduler =            selinux_task_setscheduler,
5837         .task_getscheduler =            selinux_task_getscheduler,
5838         .task_movememory =              selinux_task_movememory,
5839         .task_kill =                    selinux_task_kill,
5840         .task_wait =                    selinux_task_wait,
5841         .task_to_inode =                selinux_task_to_inode,
5842
5843         .ipc_permission =               selinux_ipc_permission,
5844         .ipc_getsecid =                 selinux_ipc_getsecid,
5845
5846         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5847         .msg_msg_free_security =        selinux_msg_msg_free_security,
5848
5849         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5850         .msg_queue_free_security =      selinux_msg_queue_free_security,
5851         .msg_queue_associate =          selinux_msg_queue_associate,
5852         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5853         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5854         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5855
5856         .shm_alloc_security =           selinux_shm_alloc_security,
5857         .shm_free_security =            selinux_shm_free_security,
5858         .shm_associate =                selinux_shm_associate,
5859         .shm_shmctl =                   selinux_shm_shmctl,
5860         .shm_shmat =                    selinux_shm_shmat,
5861
5862         .sem_alloc_security =           selinux_sem_alloc_security,
5863         .sem_free_security =            selinux_sem_free_security,
5864         .sem_associate =                selinux_sem_associate,
5865         .sem_semctl =                   selinux_sem_semctl,
5866         .sem_semop =                    selinux_sem_semop,
5867
5868         .d_instantiate =                selinux_d_instantiate,
5869
5870         .getprocattr =                  selinux_getprocattr,
5871         .setprocattr =                  selinux_setprocattr,
5872
5873         .ismaclabel =                   selinux_ismaclabel,
5874         .secid_to_secctx =              selinux_secid_to_secctx,
5875         .secctx_to_secid =              selinux_secctx_to_secid,
5876         .release_secctx =               selinux_release_secctx,
5877         .inode_notifysecctx =           selinux_inode_notifysecctx,
5878         .inode_setsecctx =              selinux_inode_setsecctx,
5879         .inode_getsecctx =              selinux_inode_getsecctx,
5880
5881         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5882         .unix_may_send =                selinux_socket_unix_may_send,
5883
5884         .socket_create =                selinux_socket_create,
5885         .socket_post_create =           selinux_socket_post_create,
5886         .socket_bind =                  selinux_socket_bind,
5887         .socket_connect =               selinux_socket_connect,
5888         .socket_listen =                selinux_socket_listen,
5889         .socket_accept =                selinux_socket_accept,
5890         .socket_sendmsg =               selinux_socket_sendmsg,
5891         .socket_recvmsg =               selinux_socket_recvmsg,
5892         .socket_getsockname =           selinux_socket_getsockname,
5893         .socket_getpeername =           selinux_socket_getpeername,
5894         .socket_getsockopt =            selinux_socket_getsockopt,
5895         .socket_setsockopt =            selinux_socket_setsockopt,
5896         .socket_shutdown =              selinux_socket_shutdown,
5897         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5898         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5899         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5900         .sk_alloc_security =            selinux_sk_alloc_security,
5901         .sk_free_security =             selinux_sk_free_security,
5902         .sk_clone_security =            selinux_sk_clone_security,
5903         .sk_getsecid =                  selinux_sk_getsecid,
5904         .sock_graft =                   selinux_sock_graft,
5905         .inet_conn_request =            selinux_inet_conn_request,
5906         .inet_csk_clone =               selinux_inet_csk_clone,
5907         .inet_conn_established =        selinux_inet_conn_established,
5908         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
5909         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
5910         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
5911         .req_classify_flow =            selinux_req_classify_flow,
5912         .tun_dev_alloc_security =       selinux_tun_dev_alloc_security,
5913         .tun_dev_free_security =        selinux_tun_dev_free_security,
5914         .tun_dev_create =               selinux_tun_dev_create,
5915         .tun_dev_attach_queue =         selinux_tun_dev_attach_queue,
5916         .tun_dev_attach =               selinux_tun_dev_attach,
5917         .tun_dev_open =                 selinux_tun_dev_open,
5918         .skb_owned_by =                 selinux_skb_owned_by,
5919
5920 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5921         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5922         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5923         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5924         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5925         .xfrm_state_alloc =             selinux_xfrm_state_alloc,
5926         .xfrm_state_alloc_acquire =     selinux_xfrm_state_alloc_acquire,
5927         .xfrm_state_free_security =     selinux_xfrm_state_free,
5928         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5929         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5930         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5931         .xfrm_decode_session =          selinux_xfrm_decode_session,
5932 #endif
5933
5934 #ifdef CONFIG_KEYS
5935         .key_alloc =                    selinux_key_alloc,
5936         .key_free =                     selinux_key_free,
5937         .key_permission =               selinux_key_permission,
5938         .key_getsecurity =              selinux_key_getsecurity,
5939 #endif
5940
5941 #ifdef CONFIG_AUDIT
5942         .audit_rule_init =              selinux_audit_rule_init,
5943         .audit_rule_known =             selinux_audit_rule_known,
5944         .audit_rule_match =             selinux_audit_rule_match,
5945         .audit_rule_free =              selinux_audit_rule_free,
5946 #endif
5947 };
5948
5949 static __init int selinux_init(void)
5950 {
5951         if (!security_module_enable(&selinux_ops)) {
5952                 selinux_enabled = 0;
5953                 return 0;
5954         }
5955
5956         if (!selinux_enabled) {
5957                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5958                 return 0;
5959         }
5960
5961         printk(KERN_INFO "SELinux:  Initializing.\n");
5962
5963         /* Set the security state for the initial task. */
5964         cred_init_security();
5965
5966         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5967
5968         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5969                                             sizeof(struct inode_security_struct),
5970                                             0, SLAB_PANIC, NULL);
5971         avc_init();
5972
5973         if (register_security(&selinux_ops))
5974                 panic("SELinux: Unable to register with kernel.\n");
5975
5976         if (selinux_enforcing)
5977                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5978         else
5979                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5980
5981         return 0;
5982 }
5983
5984 static void delayed_superblock_init(struct super_block *sb, void *unused)
5985 {
5986         superblock_doinit(sb, NULL);
5987 }
5988
5989 void selinux_complete_init(void)
5990 {
5991         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5992
5993         /* Set up any superblocks initialized prior to the policy load. */
5994         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5995         iterate_supers(delayed_superblock_init, NULL);
5996 }
5997
5998 /* SELinux requires early initialization in order to label
5999    all processes and objects when they are created. */
6000 security_initcall(selinux_init);
6001
6002 #if defined(CONFIG_NETFILTER)
6003
6004 static struct nf_hook_ops selinux_ipv4_ops[] = {
6005         {
6006                 .hook =         selinux_ipv4_postroute,
6007                 .owner =        THIS_MODULE,
6008                 .pf =           NFPROTO_IPV4,
6009                 .hooknum =      NF_INET_POST_ROUTING,
6010                 .priority =     NF_IP_PRI_SELINUX_LAST,
6011         },
6012         {
6013                 .hook =         selinux_ipv4_forward,
6014                 .owner =        THIS_MODULE,
6015                 .pf =           NFPROTO_IPV4,
6016                 .hooknum =      NF_INET_FORWARD,
6017                 .priority =     NF_IP_PRI_SELINUX_FIRST,
6018         },
6019         {
6020                 .hook =         selinux_ipv4_output,
6021                 .owner =        THIS_MODULE,
6022                 .pf =           NFPROTO_IPV4,
6023                 .hooknum =      NF_INET_LOCAL_OUT,
6024                 .priority =     NF_IP_PRI_SELINUX_FIRST,
6025         }
6026 };
6027
6028 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6029
6030 static struct nf_hook_ops selinux_ipv6_ops[] = {
6031         {
6032                 .hook =         selinux_ipv6_postroute,
6033                 .owner =        THIS_MODULE,
6034                 .pf =           NFPROTO_IPV6,
6035                 .hooknum =      NF_INET_POST_ROUTING,
6036                 .priority =     NF_IP6_PRI_SELINUX_LAST,
6037         },
6038         {
6039                 .hook =         selinux_ipv6_forward,
6040                 .owner =        THIS_MODULE,
6041                 .pf =           NFPROTO_IPV6,
6042                 .hooknum =      NF_INET_FORWARD,
6043                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
6044         }
6045 };
6046
6047 #endif  /* IPV6 */
6048
6049 static int __init selinux_nf_ip_init(void)
6050 {
6051         int err = 0;
6052
6053         if (!selinux_enabled)
6054                 goto out;
6055
6056         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
6057
6058         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
6059         if (err)
6060                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
6061
6062 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6063         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
6064         if (err)
6065                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
6066 #endif  /* IPV6 */
6067
6068 out:
6069         return err;
6070 }
6071
6072 __initcall(selinux_nf_ip_init);
6073
6074 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
6075 static void selinux_nf_ip_exit(void)
6076 {
6077         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
6078
6079         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
6080 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6081         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
6082 #endif  /* IPV6 */
6083 }
6084 #endif
6085
6086 #else /* CONFIG_NETFILTER */
6087
6088 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
6089 #define selinux_nf_ip_exit()
6090 #endif
6091
6092 #endif /* CONFIG_NETFILTER */
6093
6094 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
6095 static int selinux_disabled;
6096
6097 int selinux_disable(void)
6098 {
6099         if (ss_initialized) {
6100                 /* Not permitted after initial policy load. */
6101                 return -EINVAL;
6102         }
6103
6104         if (selinux_disabled) {
6105                 /* Only do this once. */
6106                 return -EINVAL;
6107         }
6108
6109         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
6110
6111         selinux_disabled = 1;
6112         selinux_enabled = 0;
6113
6114         reset_security_ops();
6115
6116         /* Try to destroy the avc node cache */
6117         avc_disable();
6118
6119         /* Unregister netfilter hooks. */
6120         selinux_nf_ip_exit();
6121
6122         /* Unregister selinuxfs. */
6123         exit_sel_fs();
6124
6125         return 0;
6126 }
6127 #endif