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 (!kstrtoul(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 (!kstrtoul(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                         /* We must have a dentry to determine the label on
1422                          * procfs inodes */
1423                         if (opt_dentry)
1424                                 /* Called from d_instantiate or
1425                                  * d_splice_alias. */
1426                                 dentry = dget(opt_dentry);
1427                         else
1428                                 /* Called from selinux_complete_init, try to
1429                                  * find a dentry. */
1430                                 dentry = d_find_alias(inode);
1431                         /*
1432                          * This can be hit on boot when a file is accessed
1433                          * before the policy is loaded.  When we load policy we
1434                          * may find inodes that have no dentry on the
1435                          * sbsec->isec_head list.  No reason to complain as
1436                          * these will get fixed up the next time we go through
1437                          * inode_doinit() with a dentry, before these inodes
1438                          * could be used again by userspace.
1439                          */
1440                         if (!dentry)
1441                                 goto out_unlock;
1442                         isec->sclass = inode_mode_to_security_class(inode->i_mode);
1443                         rc = selinux_proc_get_sid(dentry, isec->sclass, &sid);
1444                         dput(dentry);
1445                         if (rc)
1446                                 goto out_unlock;
1447                         isec->sid = sid;
1448                 }
1449                 break;
1450         }
1451
1452         isec->initialized = 1;
1453
1454 out_unlock:
1455         mutex_unlock(&isec->lock);
1456 out:
1457         if (isec->sclass == SECCLASS_FILE)
1458                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1459         return rc;
1460 }
1461
1462 /* Convert a Linux signal to an access vector. */
1463 static inline u32 signal_to_av(int sig)
1464 {
1465         u32 perm = 0;
1466
1467         switch (sig) {
1468         case SIGCHLD:
1469                 /* Commonly granted from child to parent. */
1470                 perm = PROCESS__SIGCHLD;
1471                 break;
1472         case SIGKILL:
1473                 /* Cannot be caught or ignored */
1474                 perm = PROCESS__SIGKILL;
1475                 break;
1476         case SIGSTOP:
1477                 /* Cannot be caught or ignored */
1478                 perm = PROCESS__SIGSTOP;
1479                 break;
1480         default:
1481                 /* All other signals. */
1482                 perm = PROCESS__SIGNAL;
1483                 break;
1484         }
1485
1486         return perm;
1487 }
1488
1489 /*
1490  * Check permission between a pair of credentials
1491  * fork check, ptrace check, etc.
1492  */
1493 static int cred_has_perm(const struct cred *actor,
1494                          const struct cred *target,
1495                          u32 perms)
1496 {
1497         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1498
1499         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1500 }
1501
1502 /*
1503  * Check permission between a pair of tasks, e.g. signal checks,
1504  * fork check, ptrace check, etc.
1505  * tsk1 is the actor and tsk2 is the target
1506  * - this uses the default subjective creds of tsk1
1507  */
1508 static int task_has_perm(const struct task_struct *tsk1,
1509                          const struct task_struct *tsk2,
1510                          u32 perms)
1511 {
1512         const struct task_security_struct *__tsec1, *__tsec2;
1513         u32 sid1, sid2;
1514
1515         rcu_read_lock();
1516         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1517         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1518         rcu_read_unlock();
1519         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1520 }
1521
1522 /*
1523  * Check permission between current and another task, e.g. signal checks,
1524  * fork check, ptrace check, etc.
1525  * current is the actor and tsk2 is the target
1526  * - this uses current's subjective creds
1527  */
1528 static int current_has_perm(const struct task_struct *tsk,
1529                             u32 perms)
1530 {
1531         u32 sid, tsid;
1532
1533         sid = current_sid();
1534         tsid = task_sid(tsk);
1535         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1536 }
1537
1538 #if CAP_LAST_CAP > 63
1539 #error Fix SELinux to handle capabilities > 63.
1540 #endif
1541
1542 /* Check whether a task is allowed to use a capability. */
1543 static int cred_has_capability(const struct cred *cred,
1544                                int cap, int audit)
1545 {
1546         struct common_audit_data ad;
1547         struct av_decision avd;
1548         u16 sclass;
1549         u32 sid = cred_sid(cred);
1550         u32 av = CAP_TO_MASK(cap);
1551         int rc;
1552
1553         ad.type = LSM_AUDIT_DATA_CAP;
1554         ad.u.cap = cap;
1555
1556         switch (CAP_TO_INDEX(cap)) {
1557         case 0:
1558                 sclass = SECCLASS_CAPABILITY;
1559                 break;
1560         case 1:
1561                 sclass = SECCLASS_CAPABILITY2;
1562                 break;
1563         default:
1564                 printk(KERN_ERR
1565                        "SELinux:  out of range capability %d\n", cap);
1566                 BUG();
1567                 return -EINVAL;
1568         }
1569
1570         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1571         if (audit == SECURITY_CAP_AUDIT) {
1572                 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad);
1573                 if (rc2)
1574                         return rc2;
1575         }
1576         return rc;
1577 }
1578
1579 /* Check whether a task is allowed to use a system operation. */
1580 static int task_has_system(struct task_struct *tsk,
1581                            u32 perms)
1582 {
1583         u32 sid = task_sid(tsk);
1584
1585         return avc_has_perm(sid, SECINITSID_KERNEL,
1586                             SECCLASS_SYSTEM, perms, NULL);
1587 }
1588
1589 /* Check whether a task has a particular permission to an inode.
1590    The 'adp' parameter is optional and allows other audit
1591    data to be passed (e.g. the dentry). */
1592 static int inode_has_perm(const struct cred *cred,
1593                           struct inode *inode,
1594                           u32 perms,
1595                           struct common_audit_data *adp)
1596 {
1597         struct inode_security_struct *isec;
1598         u32 sid;
1599
1600         validate_creds(cred);
1601
1602         if (unlikely(IS_PRIVATE(inode)))
1603                 return 0;
1604
1605         sid = cred_sid(cred);
1606         isec = inode->i_security;
1607
1608         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1609 }
1610
1611 /* Same as inode_has_perm, but pass explicit audit data containing
1612    the dentry to help the auditing code to more easily generate the
1613    pathname if needed. */
1614 static inline int dentry_has_perm(const struct cred *cred,
1615                                   struct dentry *dentry,
1616                                   u32 av)
1617 {
1618         struct inode *inode = dentry->d_inode;
1619         struct common_audit_data ad;
1620
1621         ad.type = LSM_AUDIT_DATA_DENTRY;
1622         ad.u.dentry = dentry;
1623         return inode_has_perm(cred, inode, av, &ad);
1624 }
1625
1626 /* Same as inode_has_perm, but pass explicit audit data containing
1627    the path to help the auditing code to more easily generate the
1628    pathname if needed. */
1629 static inline int path_has_perm(const struct cred *cred,
1630                                 struct path *path,
1631                                 u32 av)
1632 {
1633         struct inode *inode = path->dentry->d_inode;
1634         struct common_audit_data ad;
1635
1636         ad.type = LSM_AUDIT_DATA_PATH;
1637         ad.u.path = *path;
1638         return inode_has_perm(cred, inode, av, &ad);
1639 }
1640
1641 /* Same as path_has_perm, but uses the inode from the file struct. */
1642 static inline int file_path_has_perm(const struct cred *cred,
1643                                      struct file *file,
1644                                      u32 av)
1645 {
1646         struct common_audit_data ad;
1647
1648         ad.type = LSM_AUDIT_DATA_PATH;
1649         ad.u.path = file->f_path;
1650         return inode_has_perm(cred, file_inode(file), av, &ad);
1651 }
1652
1653 /* Check whether a task can use an open file descriptor to
1654    access an inode in a given way.  Check access to the
1655    descriptor itself, and then use dentry_has_perm to
1656    check a particular permission to the file.
1657    Access to the descriptor is implicitly granted if it
1658    has the same SID as the process.  If av is zero, then
1659    access to the file is not checked, e.g. for cases
1660    where only the descriptor is affected like seek. */
1661 static int file_has_perm(const struct cred *cred,
1662                          struct file *file,
1663                          u32 av)
1664 {
1665         struct file_security_struct *fsec = file->f_security;
1666         struct inode *inode = file_inode(file);
1667         struct common_audit_data ad;
1668         u32 sid = cred_sid(cred);
1669         int rc;
1670
1671         ad.type = LSM_AUDIT_DATA_PATH;
1672         ad.u.path = file->f_path;
1673
1674         if (sid != fsec->sid) {
1675                 rc = avc_has_perm(sid, fsec->sid,
1676                                   SECCLASS_FD,
1677                                   FD__USE,
1678                                   &ad);
1679                 if (rc)
1680                         goto out;
1681         }
1682
1683         /* av is zero if only checking access to the descriptor. */
1684         rc = 0;
1685         if (av)
1686                 rc = inode_has_perm(cred, inode, av, &ad);
1687
1688 out:
1689         return rc;
1690 }
1691
1692 /* Check whether a task can create a file. */
1693 static int may_create(struct inode *dir,
1694                       struct dentry *dentry,
1695                       u16 tclass)
1696 {
1697         const struct task_security_struct *tsec = current_security();
1698         struct inode_security_struct *dsec;
1699         struct superblock_security_struct *sbsec;
1700         u32 sid, newsid;
1701         struct common_audit_data ad;
1702         int rc;
1703
1704         dsec = dir->i_security;
1705         sbsec = dir->i_sb->s_security;
1706
1707         sid = tsec->sid;
1708         newsid = tsec->create_sid;
1709
1710         ad.type = LSM_AUDIT_DATA_DENTRY;
1711         ad.u.dentry = dentry;
1712
1713         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1714                           DIR__ADD_NAME | DIR__SEARCH,
1715                           &ad);
1716         if (rc)
1717                 return rc;
1718
1719         if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
1720                 rc = security_transition_sid(sid, dsec->sid, tclass,
1721                                              &dentry->d_name, &newsid);
1722                 if (rc)
1723                         return rc;
1724         }
1725
1726         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1727         if (rc)
1728                 return rc;
1729
1730         return avc_has_perm(newsid, sbsec->sid,
1731                             SECCLASS_FILESYSTEM,
1732                             FILESYSTEM__ASSOCIATE, &ad);
1733 }
1734
1735 /* Check whether a task can create a key. */
1736 static int may_create_key(u32 ksid,
1737                           struct task_struct *ctx)
1738 {
1739         u32 sid = task_sid(ctx);
1740
1741         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1742 }
1743
1744 #define MAY_LINK        0
1745 #define MAY_UNLINK      1
1746 #define MAY_RMDIR       2
1747
1748 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1749 static int may_link(struct inode *dir,
1750                     struct dentry *dentry,
1751                     int kind)
1752
1753 {
1754         struct inode_security_struct *dsec, *isec;
1755         struct common_audit_data ad;
1756         u32 sid = current_sid();
1757         u32 av;
1758         int rc;
1759
1760         dsec = dir->i_security;
1761         isec = dentry->d_inode->i_security;
1762
1763         ad.type = LSM_AUDIT_DATA_DENTRY;
1764         ad.u.dentry = dentry;
1765
1766         av = DIR__SEARCH;
1767         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1768         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1769         if (rc)
1770                 return rc;
1771
1772         switch (kind) {
1773         case MAY_LINK:
1774                 av = FILE__LINK;
1775                 break;
1776         case MAY_UNLINK:
1777                 av = FILE__UNLINK;
1778                 break;
1779         case MAY_RMDIR:
1780                 av = DIR__RMDIR;
1781                 break;
1782         default:
1783                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1784                         __func__, kind);
1785                 return 0;
1786         }
1787
1788         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1789         return rc;
1790 }
1791
1792 static inline int may_rename(struct inode *old_dir,
1793                              struct dentry *old_dentry,
1794                              struct inode *new_dir,
1795                              struct dentry *new_dentry)
1796 {
1797         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1798         struct common_audit_data ad;
1799         u32 sid = current_sid();
1800         u32 av;
1801         int old_is_dir, new_is_dir;
1802         int rc;
1803
1804         old_dsec = old_dir->i_security;
1805         old_isec = old_dentry->d_inode->i_security;
1806         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1807         new_dsec = new_dir->i_security;
1808
1809         ad.type = LSM_AUDIT_DATA_DENTRY;
1810
1811         ad.u.dentry = old_dentry;
1812         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1813                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1814         if (rc)
1815                 return rc;
1816         rc = avc_has_perm(sid, old_isec->sid,
1817                           old_isec->sclass, FILE__RENAME, &ad);
1818         if (rc)
1819                 return rc;
1820         if (old_is_dir && new_dir != old_dir) {
1821                 rc = avc_has_perm(sid, old_isec->sid,
1822                                   old_isec->sclass, DIR__REPARENT, &ad);
1823                 if (rc)
1824                         return rc;
1825         }
1826
1827         ad.u.dentry = new_dentry;
1828         av = DIR__ADD_NAME | DIR__SEARCH;
1829         if (new_dentry->d_inode)
1830                 av |= DIR__REMOVE_NAME;
1831         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1832         if (rc)
1833                 return rc;
1834         if (new_dentry->d_inode) {
1835                 new_isec = new_dentry->d_inode->i_security;
1836                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1837                 rc = avc_has_perm(sid, new_isec->sid,
1838                                   new_isec->sclass,
1839                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1840                 if (rc)
1841                         return rc;
1842         }
1843
1844         return 0;
1845 }
1846
1847 /* Check whether a task can perform a filesystem operation. */
1848 static int superblock_has_perm(const struct cred *cred,
1849                                struct super_block *sb,
1850                                u32 perms,
1851                                struct common_audit_data *ad)
1852 {
1853         struct superblock_security_struct *sbsec;
1854         u32 sid = cred_sid(cred);
1855
1856         sbsec = sb->s_security;
1857         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1858 }
1859
1860 /* Convert a Linux mode and permission mask to an access vector. */
1861 static inline u32 file_mask_to_av(int mode, int mask)
1862 {
1863         u32 av = 0;
1864
1865         if (!S_ISDIR(mode)) {
1866                 if (mask & MAY_EXEC)
1867                         av |= FILE__EXECUTE;
1868                 if (mask & MAY_READ)
1869                         av |= FILE__READ;
1870
1871                 if (mask & MAY_APPEND)
1872                         av |= FILE__APPEND;
1873                 else if (mask & MAY_WRITE)
1874                         av |= FILE__WRITE;
1875
1876         } else {
1877                 if (mask & MAY_EXEC)
1878                         av |= DIR__SEARCH;
1879                 if (mask & MAY_WRITE)
1880                         av |= DIR__WRITE;
1881                 if (mask & MAY_READ)
1882                         av |= DIR__READ;
1883         }
1884
1885         return av;
1886 }
1887
1888 /* Convert a Linux file to an access vector. */
1889 static inline u32 file_to_av(struct file *file)
1890 {
1891         u32 av = 0;
1892
1893         if (file->f_mode & FMODE_READ)
1894                 av |= FILE__READ;
1895         if (file->f_mode & FMODE_WRITE) {
1896                 if (file->f_flags & O_APPEND)
1897                         av |= FILE__APPEND;
1898                 else
1899                         av |= FILE__WRITE;
1900         }
1901         if (!av) {
1902                 /*
1903                  * Special file opened with flags 3 for ioctl-only use.
1904                  */
1905                 av = FILE__IOCTL;
1906         }
1907
1908         return av;
1909 }
1910
1911 /*
1912  * Convert a file to an access vector and include the correct open
1913  * open permission.
1914  */
1915 static inline u32 open_file_to_av(struct file *file)
1916 {
1917         u32 av = file_to_av(file);
1918
1919         if (selinux_policycap_openperm)
1920                 av |= FILE__OPEN;
1921
1922         return av;
1923 }
1924
1925 /* Hook functions begin here. */
1926
1927 static int selinux_ptrace_access_check(struct task_struct *child,
1928                                      unsigned int mode)
1929 {
1930         int rc;
1931
1932         rc = cap_ptrace_access_check(child, mode);
1933         if (rc)
1934                 return rc;
1935
1936         if (mode & PTRACE_MODE_READ) {
1937                 u32 sid = current_sid();
1938                 u32 csid = task_sid(child);
1939                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1940         }
1941
1942         return current_has_perm(child, PROCESS__PTRACE);
1943 }
1944
1945 static int selinux_ptrace_traceme(struct task_struct *parent)
1946 {
1947         int rc;
1948
1949         rc = cap_ptrace_traceme(parent);
1950         if (rc)
1951                 return rc;
1952
1953         return task_has_perm(parent, current, PROCESS__PTRACE);
1954 }
1955
1956 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1957                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1958 {
1959         int error;
1960
1961         error = current_has_perm(target, PROCESS__GETCAP);
1962         if (error)
1963                 return error;
1964
1965         return cap_capget(target, effective, inheritable, permitted);
1966 }
1967
1968 static int selinux_capset(struct cred *new, const struct cred *old,
1969                           const kernel_cap_t *effective,
1970                           const kernel_cap_t *inheritable,
1971                           const kernel_cap_t *permitted)
1972 {
1973         int error;
1974
1975         error = cap_capset(new, old,
1976                                       effective, inheritable, permitted);
1977         if (error)
1978                 return error;
1979
1980         return cred_has_perm(old, new, PROCESS__SETCAP);
1981 }
1982
1983 /*
1984  * (This comment used to live with the selinux_task_setuid hook,
1985  * which was removed).
1986  *
1987  * Since setuid only affects the current process, and since the SELinux
1988  * controls are not based on the Linux identity attributes, SELinux does not
1989  * need to control this operation.  However, SELinux does control the use of
1990  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1991  */
1992
1993 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
1994                            int cap, int audit)
1995 {
1996         int rc;
1997
1998         rc = cap_capable(cred, ns, cap, audit);
1999         if (rc)
2000                 return rc;
2001
2002         return cred_has_capability(cred, cap, audit);
2003 }
2004
2005 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2006 {
2007         const struct cred *cred = current_cred();
2008         int rc = 0;
2009
2010         if (!sb)
2011                 return 0;
2012
2013         switch (cmds) {
2014         case Q_SYNC:
2015         case Q_QUOTAON:
2016         case Q_QUOTAOFF:
2017         case Q_SETINFO:
2018         case Q_SETQUOTA:
2019                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2020                 break;
2021         case Q_GETFMT:
2022         case Q_GETINFO:
2023         case Q_GETQUOTA:
2024                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2025                 break;
2026         default:
2027                 rc = 0;  /* let the kernel handle invalid cmds */
2028                 break;
2029         }
2030         return rc;
2031 }
2032
2033 static int selinux_quota_on(struct dentry *dentry)
2034 {
2035         const struct cred *cred = current_cred();
2036
2037         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2038 }
2039
2040 static int selinux_syslog(int type)
2041 {
2042         int rc;
2043
2044         switch (type) {
2045         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2046         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2047                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2048                 break;
2049         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2050         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2051         /* Set level of messages printed to console */
2052         case SYSLOG_ACTION_CONSOLE_LEVEL:
2053                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2054                 break;
2055         case SYSLOG_ACTION_CLOSE:       /* Close log */
2056         case SYSLOG_ACTION_OPEN:        /* Open log */
2057         case SYSLOG_ACTION_READ:        /* Read from log */
2058         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
2059         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
2060         default:
2061                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2062                 break;
2063         }
2064         return rc;
2065 }
2066
2067 /*
2068  * Check that a process has enough memory to allocate a new virtual
2069  * mapping. 0 means there is enough memory for the allocation to
2070  * succeed and -ENOMEM implies there is not.
2071  *
2072  * Do not audit the selinux permission check, as this is applied to all
2073  * processes that allocate mappings.
2074  */
2075 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2076 {
2077         int rc, cap_sys_admin = 0;
2078
2079         rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
2080                              SECURITY_CAP_NOAUDIT);
2081         if (rc == 0)
2082                 cap_sys_admin = 1;
2083
2084         return __vm_enough_memory(mm, pages, cap_sys_admin);
2085 }
2086
2087 /* binprm security operations */
2088
2089 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2090 {
2091         const struct task_security_struct *old_tsec;
2092         struct task_security_struct *new_tsec;
2093         struct inode_security_struct *isec;
2094         struct common_audit_data ad;
2095         struct inode *inode = file_inode(bprm->file);
2096         int rc;
2097
2098         rc = cap_bprm_set_creds(bprm);
2099         if (rc)
2100                 return rc;
2101
2102         /* SELinux context only depends on initial program or script and not
2103          * the script interpreter */
2104         if (bprm->cred_prepared)
2105                 return 0;
2106
2107         old_tsec = current_security();
2108         new_tsec = bprm->cred->security;
2109         isec = inode->i_security;
2110
2111         /* Default to the current task SID. */
2112         new_tsec->sid = old_tsec->sid;
2113         new_tsec->osid = old_tsec->sid;
2114
2115         /* Reset fs, key, and sock SIDs on execve. */
2116         new_tsec->create_sid = 0;
2117         new_tsec->keycreate_sid = 0;
2118         new_tsec->sockcreate_sid = 0;
2119
2120         if (old_tsec->exec_sid) {
2121                 new_tsec->sid = old_tsec->exec_sid;
2122                 /* Reset exec SID on execve. */
2123                 new_tsec->exec_sid = 0;
2124
2125                 /*
2126                  * Minimize confusion: if no_new_privs and a transition is
2127                  * explicitly requested, then fail the exec.
2128                  */
2129                 if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)
2130                         return -EPERM;
2131         } else {
2132                 /* Check for a default transition on this program. */
2133                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2134                                              SECCLASS_PROCESS, NULL,
2135                                              &new_tsec->sid);
2136                 if (rc)
2137                         return rc;
2138         }
2139
2140         ad.type = LSM_AUDIT_DATA_PATH;
2141         ad.u.path = bprm->file->f_path;
2142
2143         if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
2144             (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2145                 new_tsec->sid = old_tsec->sid;
2146
2147         if (new_tsec->sid == old_tsec->sid) {
2148                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2149                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2150                 if (rc)
2151                         return rc;
2152         } else {
2153                 /* Check permissions for the transition. */
2154                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2155                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2156                 if (rc)
2157                         return rc;
2158
2159                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2160                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2161                 if (rc)
2162                         return rc;
2163
2164                 /* Check for shared state */
2165                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2166                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2167                                           SECCLASS_PROCESS, PROCESS__SHARE,
2168                                           NULL);
2169                         if (rc)
2170                                 return -EPERM;
2171                 }
2172
2173                 /* Make sure that anyone attempting to ptrace over a task that
2174                  * changes its SID has the appropriate permit */
2175                 if (bprm->unsafe &
2176                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2177                         struct task_struct *tracer;
2178                         struct task_security_struct *sec;
2179                         u32 ptsid = 0;
2180
2181                         rcu_read_lock();
2182                         tracer = ptrace_parent(current);
2183                         if (likely(tracer != NULL)) {
2184                                 sec = __task_cred(tracer)->security;
2185                                 ptsid = sec->sid;
2186                         }
2187                         rcu_read_unlock();
2188
2189                         if (ptsid != 0) {
2190                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2191                                                   SECCLASS_PROCESS,
2192                                                   PROCESS__PTRACE, NULL);
2193                                 if (rc)
2194                                         return -EPERM;
2195                         }
2196                 }
2197
2198                 /* Clear any possibly unsafe personality bits on exec: */
2199                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2200         }
2201
2202         return 0;
2203 }
2204
2205 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2206 {
2207         const struct task_security_struct *tsec = current_security();
2208         u32 sid, osid;
2209         int atsecure = 0;
2210
2211         sid = tsec->sid;
2212         osid = tsec->osid;
2213
2214         if (osid != sid) {
2215                 /* Enable secure mode for SIDs transitions unless
2216                    the noatsecure permission is granted between
2217                    the two SIDs, i.e. ahp returns 0. */
2218                 atsecure = avc_has_perm(osid, sid,
2219                                         SECCLASS_PROCESS,
2220                                         PROCESS__NOATSECURE, NULL);
2221         }
2222
2223         return (atsecure || cap_bprm_secureexec(bprm));
2224 }
2225
2226 static int match_file(const void *p, struct file *file, unsigned fd)
2227 {
2228         return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2229 }
2230
2231 /* Derived from fs/exec.c:flush_old_files. */
2232 static inline void flush_unauthorized_files(const struct cred *cred,
2233                                             struct files_struct *files)
2234 {
2235         struct file *file, *devnull = NULL;
2236         struct tty_struct *tty;
2237         int drop_tty = 0;
2238         unsigned n;
2239
2240         tty = get_current_tty();
2241         if (tty) {
2242                 spin_lock(&tty_files_lock);
2243                 if (!list_empty(&tty->tty_files)) {
2244                         struct tty_file_private *file_priv;
2245
2246                         /* Revalidate access to controlling tty.
2247                            Use file_path_has_perm on the tty path directly
2248                            rather than using file_has_perm, as this particular
2249                            open file may belong to another process and we are
2250                            only interested in the inode-based check here. */
2251                         file_priv = list_first_entry(&tty->tty_files,
2252                                                 struct tty_file_private, list);
2253                         file = file_priv->file;
2254                         if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2255                                 drop_tty = 1;
2256                 }
2257                 spin_unlock(&tty_files_lock);
2258                 tty_kref_put(tty);
2259         }
2260         /* Reset controlling tty. */
2261         if (drop_tty)
2262                 no_tty();
2263
2264         /* Revalidate access to inherited open files. */
2265         n = iterate_fd(files, 0, match_file, cred);
2266         if (!n) /* none found? */
2267                 return;
2268
2269         devnull = dentry_open(&selinux_null, O_RDWR, cred);
2270         if (IS_ERR(devnull))
2271                 devnull = NULL;
2272         /* replace all the matching ones with this */
2273         do {
2274                 replace_fd(n - 1, devnull, 0);
2275         } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2276         if (devnull)
2277                 fput(devnull);
2278 }
2279
2280 /*
2281  * Prepare a process for imminent new credential changes due to exec
2282  */
2283 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2284 {
2285         struct task_security_struct *new_tsec;
2286         struct rlimit *rlim, *initrlim;
2287         int rc, i;
2288
2289         new_tsec = bprm->cred->security;
2290         if (new_tsec->sid == new_tsec->osid)
2291                 return;
2292
2293         /* Close files for which the new task SID is not authorized. */
2294         flush_unauthorized_files(bprm->cred, current->files);
2295
2296         /* Always clear parent death signal on SID transitions. */
2297         current->pdeath_signal = 0;
2298
2299         /* Check whether the new SID can inherit resource limits from the old
2300          * SID.  If not, reset all soft limits to the lower of the current
2301          * task's hard limit and the init task's soft limit.
2302          *
2303          * Note that the setting of hard limits (even to lower them) can be
2304          * controlled by the setrlimit check.  The inclusion of the init task's
2305          * soft limit into the computation is to avoid resetting soft limits
2306          * higher than the default soft limit for cases where the default is
2307          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2308          */
2309         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2310                           PROCESS__RLIMITINH, NULL);
2311         if (rc) {
2312                 /* protect against do_prlimit() */
2313                 task_lock(current);
2314                 for (i = 0; i < RLIM_NLIMITS; i++) {
2315                         rlim = current->signal->rlim + i;
2316                         initrlim = init_task.signal->rlim + i;
2317                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2318                 }
2319                 task_unlock(current);
2320                 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2321         }
2322 }
2323
2324 /*
2325  * Clean up the process immediately after the installation of new credentials
2326  * due to exec
2327  */
2328 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2329 {
2330         const struct task_security_struct *tsec = current_security();
2331         struct itimerval itimer;
2332         u32 osid, sid;
2333         int rc, i;
2334
2335         osid = tsec->osid;
2336         sid = tsec->sid;
2337
2338         if (sid == osid)
2339                 return;
2340
2341         /* Check whether the new SID can inherit signal state from the old SID.
2342          * If not, clear itimers to avoid subsequent signal generation and
2343          * flush and unblock signals.
2344          *
2345          * This must occur _after_ the task SID has been updated so that any
2346          * kill done after the flush will be checked against the new SID.
2347          */
2348         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2349         if (rc) {
2350                 memset(&itimer, 0, sizeof itimer);
2351                 for (i = 0; i < 3; i++)
2352                         do_setitimer(i, &itimer, NULL);
2353                 spin_lock_irq(&current->sighand->siglock);
2354                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2355                         __flush_signals(current);
2356                         flush_signal_handlers(current, 1);
2357                         sigemptyset(&current->blocked);
2358                 }
2359                 spin_unlock_irq(&current->sighand->siglock);
2360         }
2361
2362         /* Wake up the parent if it is waiting so that it can recheck
2363          * wait permission to the new task SID. */
2364         read_lock(&tasklist_lock);
2365         __wake_up_parent(current, current->real_parent);
2366         read_unlock(&tasklist_lock);
2367 }
2368
2369 /* superblock security operations */
2370
2371 static int selinux_sb_alloc_security(struct super_block *sb)
2372 {
2373         return superblock_alloc_security(sb);
2374 }
2375
2376 static void selinux_sb_free_security(struct super_block *sb)
2377 {
2378         superblock_free_security(sb);
2379 }
2380
2381 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2382 {
2383         if (plen > olen)
2384                 return 0;
2385
2386         return !memcmp(prefix, option, plen);
2387 }
2388
2389 static inline int selinux_option(char *option, int len)
2390 {
2391         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2392                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2393                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2394                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2395                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2396 }
2397
2398 static inline void take_option(char **to, char *from, int *first, int len)
2399 {
2400         if (!*first) {
2401                 **to = ',';
2402                 *to += 1;
2403         } else
2404                 *first = 0;
2405         memcpy(*to, from, len);
2406         *to += len;
2407 }
2408
2409 static inline void take_selinux_option(char **to, char *from, int *first,
2410                                        int len)
2411 {
2412         int current_size = 0;
2413
2414         if (!*first) {
2415                 **to = '|';
2416                 *to += 1;
2417         } else
2418                 *first = 0;
2419
2420         while (current_size < len) {
2421                 if (*from != '"') {
2422                         **to = *from;
2423                         *to += 1;
2424                 }
2425                 from += 1;
2426                 current_size += 1;
2427         }
2428 }
2429
2430 static int selinux_sb_copy_data(char *orig, char *copy)
2431 {
2432         int fnosec, fsec, rc = 0;
2433         char *in_save, *in_curr, *in_end;
2434         char *sec_curr, *nosec_save, *nosec;
2435         int open_quote = 0;
2436
2437         in_curr = orig;
2438         sec_curr = copy;
2439
2440         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2441         if (!nosec) {
2442                 rc = -ENOMEM;
2443                 goto out;
2444         }
2445
2446         nosec_save = nosec;
2447         fnosec = fsec = 1;
2448         in_save = in_end = orig;
2449
2450         do {
2451                 if (*in_end == '"')
2452                         open_quote = !open_quote;
2453                 if ((*in_end == ',' && open_quote == 0) ||
2454                                 *in_end == '\0') {
2455                         int len = in_end - in_curr;
2456
2457                         if (selinux_option(in_curr, len))
2458                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2459                         else
2460                                 take_option(&nosec, in_curr, &fnosec, len);
2461
2462                         in_curr = in_end + 1;
2463                 }
2464         } while (*in_end++);
2465
2466         strcpy(in_save, nosec_save);
2467         free_page((unsigned long)nosec_save);
2468 out:
2469         return rc;
2470 }
2471
2472 static int selinux_sb_remount(struct super_block *sb, void *data)
2473 {
2474         int rc, i, *flags;
2475         struct security_mnt_opts opts;
2476         char *secdata, **mount_options;
2477         struct superblock_security_struct *sbsec = sb->s_security;
2478
2479         if (!(sbsec->flags & SE_SBINITIALIZED))
2480                 return 0;
2481
2482         if (!data)
2483                 return 0;
2484
2485         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2486                 return 0;
2487
2488         security_init_mnt_opts(&opts);
2489         secdata = alloc_secdata();
2490         if (!secdata)
2491                 return -ENOMEM;
2492         rc = selinux_sb_copy_data(data, secdata);
2493         if (rc)
2494                 goto out_free_secdata;
2495
2496         rc = selinux_parse_opts_str(secdata, &opts);
2497         if (rc)
2498                 goto out_free_secdata;
2499
2500         mount_options = opts.mnt_opts;
2501         flags = opts.mnt_opts_flags;
2502
2503         for (i = 0; i < opts.num_mnt_opts; i++) {
2504                 u32 sid;
2505                 size_t len;
2506
2507                 if (flags[i] == SBLABEL_MNT)
2508                         continue;
2509                 len = strlen(mount_options[i]);
2510                 rc = security_context_to_sid(mount_options[i], len, &sid,
2511                                              GFP_KERNEL);
2512                 if (rc) {
2513                         printk(KERN_WARNING "SELinux: security_context_to_sid"
2514                                "(%s) failed for (dev %s, type %s) errno=%d\n",
2515                                mount_options[i], sb->s_id, sb->s_type->name, rc);
2516                         goto out_free_opts;
2517                 }
2518                 rc = -EINVAL;
2519                 switch (flags[i]) {
2520                 case FSCONTEXT_MNT:
2521                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2522                                 goto out_bad_option;
2523                         break;
2524                 case CONTEXT_MNT:
2525                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2526                                 goto out_bad_option;
2527                         break;
2528                 case ROOTCONTEXT_MNT: {
2529                         struct inode_security_struct *root_isec;
2530                         root_isec = sb->s_root->d_inode->i_security;
2531
2532                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2533                                 goto out_bad_option;
2534                         break;
2535                 }
2536                 case DEFCONTEXT_MNT:
2537                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2538                                 goto out_bad_option;
2539                         break;
2540                 default:
2541                         goto out_free_opts;
2542                 }
2543         }
2544
2545         rc = 0;
2546 out_free_opts:
2547         security_free_mnt_opts(&opts);
2548 out_free_secdata:
2549         free_secdata(secdata);
2550         return rc;
2551 out_bad_option:
2552         printk(KERN_WARNING "SELinux: unable to change security options "
2553                "during remount (dev %s, type=%s)\n", sb->s_id,
2554                sb->s_type->name);
2555         goto out_free_opts;
2556 }
2557
2558 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2559 {
2560         const struct cred *cred = current_cred();
2561         struct common_audit_data ad;
2562         int rc;
2563
2564         rc = superblock_doinit(sb, data);
2565         if (rc)
2566                 return rc;
2567
2568         /* Allow all mounts performed by the kernel */
2569         if (flags & MS_KERNMOUNT)
2570                 return 0;
2571
2572         ad.type = LSM_AUDIT_DATA_DENTRY;
2573         ad.u.dentry = sb->s_root;
2574         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2575 }
2576
2577 static int selinux_sb_statfs(struct dentry *dentry)
2578 {
2579         const struct cred *cred = current_cred();
2580         struct common_audit_data ad;
2581
2582         ad.type = LSM_AUDIT_DATA_DENTRY;
2583         ad.u.dentry = dentry->d_sb->s_root;
2584         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2585 }
2586
2587 static int selinux_mount(const char *dev_name,
2588                          struct path *path,
2589                          const char *type,
2590                          unsigned long flags,
2591                          void *data)
2592 {
2593         const struct cred *cred = current_cred();
2594
2595         if (flags & MS_REMOUNT)
2596                 return superblock_has_perm(cred, path->dentry->d_sb,
2597                                            FILESYSTEM__REMOUNT, NULL);
2598         else
2599                 return path_has_perm(cred, path, FILE__MOUNTON);
2600 }
2601
2602 static int selinux_umount(struct vfsmount *mnt, int flags)
2603 {
2604         const struct cred *cred = current_cred();
2605
2606         return superblock_has_perm(cred, mnt->mnt_sb,
2607                                    FILESYSTEM__UNMOUNT, NULL);
2608 }
2609
2610 /* inode security operations */
2611
2612 static int selinux_inode_alloc_security(struct inode *inode)
2613 {
2614         return inode_alloc_security(inode);
2615 }
2616
2617 static void selinux_inode_free_security(struct inode *inode)
2618 {
2619         inode_free_security(inode);
2620 }
2621
2622 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2623                                         struct qstr *name, void **ctx,
2624                                         u32 *ctxlen)
2625 {
2626         const struct cred *cred = current_cred();
2627         struct task_security_struct *tsec;
2628         struct inode_security_struct *dsec;
2629         struct superblock_security_struct *sbsec;
2630         struct inode *dir = dentry->d_parent->d_inode;
2631         u32 newsid;
2632         int rc;
2633
2634         tsec = cred->security;
2635         dsec = dir->i_security;
2636         sbsec = dir->i_sb->s_security;
2637
2638         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2639                 newsid = tsec->create_sid;
2640         } else {
2641                 rc = security_transition_sid(tsec->sid, dsec->sid,
2642                                              inode_mode_to_security_class(mode),
2643                                              name,
2644                                              &newsid);
2645                 if (rc) {
2646                         printk(KERN_WARNING
2647                                 "%s: security_transition_sid failed, rc=%d\n",
2648                                __func__, -rc);
2649                         return rc;
2650                 }
2651         }
2652
2653         return security_sid_to_context(newsid, (char **)ctx, ctxlen);
2654 }
2655
2656 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2657                                        const struct qstr *qstr,
2658                                        const char **name,
2659                                        void **value, size_t *len)
2660 {
2661         const struct task_security_struct *tsec = current_security();
2662         struct inode_security_struct *dsec;
2663         struct superblock_security_struct *sbsec;
2664         u32 sid, newsid, clen;
2665         int rc;
2666         char *context;
2667
2668         dsec = dir->i_security;
2669         sbsec = dir->i_sb->s_security;
2670
2671         sid = tsec->sid;
2672         newsid = tsec->create_sid;
2673
2674         if ((sbsec->flags & SE_SBINITIALIZED) &&
2675             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2676                 newsid = sbsec->mntpoint_sid;
2677         else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
2678                 rc = security_transition_sid(sid, dsec->sid,
2679                                              inode_mode_to_security_class(inode->i_mode),
2680                                              qstr, &newsid);
2681                 if (rc) {
2682                         printk(KERN_WARNING "%s:  "
2683                                "security_transition_sid failed, rc=%d (dev=%s "
2684                                "ino=%ld)\n",
2685                                __func__,
2686                                -rc, inode->i_sb->s_id, inode->i_ino);
2687                         return rc;
2688                 }
2689         }
2690
2691         /* Possibly defer initialization to selinux_complete_init. */
2692         if (sbsec->flags & SE_SBINITIALIZED) {
2693                 struct inode_security_struct *isec = inode->i_security;
2694                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2695                 isec->sid = newsid;
2696                 isec->initialized = 1;
2697         }
2698
2699         if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2700                 return -EOPNOTSUPP;
2701
2702         if (name)
2703                 *name = XATTR_SELINUX_SUFFIX;
2704
2705         if (value && len) {
2706                 rc = security_sid_to_context_force(newsid, &context, &clen);
2707                 if (rc)
2708                         return rc;
2709                 *value = context;
2710                 *len = clen;
2711         }
2712
2713         return 0;
2714 }
2715
2716 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2717 {
2718         return may_create(dir, dentry, SECCLASS_FILE);
2719 }
2720
2721 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2722 {
2723         return may_link(dir, old_dentry, MAY_LINK);
2724 }
2725
2726 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2727 {
2728         return may_link(dir, dentry, MAY_UNLINK);
2729 }
2730
2731 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2732 {
2733         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2734 }
2735
2736 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2737 {
2738         return may_create(dir, dentry, SECCLASS_DIR);
2739 }
2740
2741 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2742 {
2743         return may_link(dir, dentry, MAY_RMDIR);
2744 }
2745
2746 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2747 {
2748         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2749 }
2750
2751 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2752                                 struct inode *new_inode, struct dentry *new_dentry)
2753 {
2754         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2755 }
2756
2757 static int selinux_inode_readlink(struct dentry *dentry)
2758 {
2759         const struct cred *cred = current_cred();
2760
2761         return dentry_has_perm(cred, dentry, FILE__READ);
2762 }
2763
2764 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2765 {
2766         const struct cred *cred = current_cred();
2767
2768         return dentry_has_perm(cred, dentry, FILE__READ);
2769 }
2770
2771 static noinline int audit_inode_permission(struct inode *inode,
2772                                            u32 perms, u32 audited, u32 denied,
2773                                            unsigned flags)
2774 {
2775         struct common_audit_data ad;
2776         struct inode_security_struct *isec = inode->i_security;
2777         int rc;
2778
2779         ad.type = LSM_AUDIT_DATA_INODE;
2780         ad.u.inode = inode;
2781
2782         rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2783                             audited, denied, &ad, flags);
2784         if (rc)
2785                 return rc;
2786         return 0;
2787 }
2788
2789 static int selinux_inode_permission(struct inode *inode, int mask)
2790 {
2791         const struct cred *cred = current_cred();
2792         u32 perms;
2793         bool from_access;
2794         unsigned flags = mask & MAY_NOT_BLOCK;
2795         struct inode_security_struct *isec;
2796         u32 sid;
2797         struct av_decision avd;
2798         int rc, rc2;
2799         u32 audited, denied;
2800
2801         from_access = mask & MAY_ACCESS;
2802         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2803
2804         /* No permission to check.  Existence test. */
2805         if (!mask)
2806                 return 0;
2807
2808         validate_creds(cred);
2809
2810         if (unlikely(IS_PRIVATE(inode)))
2811                 return 0;
2812
2813         perms = file_mask_to_av(inode->i_mode, mask);
2814
2815         sid = cred_sid(cred);
2816         isec = inode->i_security;
2817
2818         rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
2819         audited = avc_audit_required(perms, &avd, rc,
2820                                      from_access ? FILE__AUDIT_ACCESS : 0,
2821                                      &denied);
2822         if (likely(!audited))
2823                 return rc;
2824
2825         rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2826         if (rc2)
2827                 return rc2;
2828         return rc;
2829 }
2830
2831 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2832 {
2833         const struct cred *cred = current_cred();
2834         unsigned int ia_valid = iattr->ia_valid;
2835         __u32 av = FILE__WRITE;
2836
2837         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2838         if (ia_valid & ATTR_FORCE) {
2839                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2840                               ATTR_FORCE);
2841                 if (!ia_valid)
2842                         return 0;
2843         }
2844
2845         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2846                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2847                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2848
2849         if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2850                 av |= FILE__OPEN;
2851
2852         return dentry_has_perm(cred, dentry, av);
2853 }
2854
2855 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2856 {
2857         const struct cred *cred = current_cred();
2858         struct path path;
2859
2860         path.dentry = dentry;
2861         path.mnt = mnt;
2862
2863         return path_has_perm(cred, &path, FILE__GETATTR);
2864 }
2865
2866 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2867 {
2868         const struct cred *cred = current_cred();
2869
2870         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2871                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2872                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2873                         if (!capable(CAP_SETFCAP))
2874                                 return -EPERM;
2875                 } else if (!capable(CAP_SYS_ADMIN)) {
2876                         /* A different attribute in the security namespace.
2877                            Restrict to administrator. */
2878                         return -EPERM;
2879                 }
2880         }
2881
2882         /* Not an attribute we recognize, so just check the
2883            ordinary setattr permission. */
2884         return dentry_has_perm(cred, dentry, FILE__SETATTR);
2885 }
2886
2887 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2888                                   const void *value, size_t size, int flags)
2889 {
2890         struct inode *inode = dentry->d_inode;
2891         struct inode_security_struct *isec = inode->i_security;
2892         struct superblock_security_struct *sbsec;
2893         struct common_audit_data ad;
2894         u32 newsid, sid = current_sid();
2895         int rc = 0;
2896
2897         if (strcmp(name, XATTR_NAME_SELINUX))
2898                 return selinux_inode_setotherxattr(dentry, name);
2899
2900         sbsec = inode->i_sb->s_security;
2901         if (!(sbsec->flags & SBLABEL_MNT))
2902                 return -EOPNOTSUPP;
2903
2904         if (!inode_owner_or_capable(inode))
2905                 return -EPERM;
2906
2907         ad.type = LSM_AUDIT_DATA_DENTRY;
2908         ad.u.dentry = dentry;
2909
2910         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2911                           FILE__RELABELFROM, &ad);
2912         if (rc)
2913                 return rc;
2914
2915         rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
2916         if (rc == -EINVAL) {
2917                 if (!capable(CAP_MAC_ADMIN)) {
2918                         struct audit_buffer *ab;
2919                         size_t audit_size;
2920                         const char *str;
2921
2922                         /* We strip a nul only if it is at the end, otherwise the
2923                          * context contains a nul and we should audit that */
2924                         if (value) {
2925                                 str = value;
2926                                 if (str[size - 1] == '\0')
2927                                         audit_size = size - 1;
2928                                 else
2929                                         audit_size = size;
2930                         } else {
2931                                 str = "";
2932                                 audit_size = 0;
2933                         }
2934                         ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
2935                         audit_log_format(ab, "op=setxattr invalid_context=");
2936                         audit_log_n_untrustedstring(ab, value, audit_size);
2937                         audit_log_end(ab);
2938
2939                         return rc;
2940                 }
2941                 rc = security_context_to_sid_force(value, size, &newsid);
2942         }
2943         if (rc)
2944                 return rc;
2945
2946         rc = avc_has_perm(sid, newsid, isec->sclass,
2947                           FILE__RELABELTO, &ad);
2948         if (rc)
2949                 return rc;
2950
2951         rc = security_validate_transition(isec->sid, newsid, sid,
2952                                           isec->sclass);
2953         if (rc)
2954                 return rc;
2955
2956         return avc_has_perm(newsid,
2957                             sbsec->sid,
2958                             SECCLASS_FILESYSTEM,
2959                             FILESYSTEM__ASSOCIATE,
2960                             &ad);
2961 }
2962
2963 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2964                                         const void *value, size_t size,
2965                                         int flags)
2966 {
2967         struct inode *inode = dentry->d_inode;
2968         struct inode_security_struct *isec = inode->i_security;
2969         u32 newsid;
2970         int rc;
2971
2972         if (strcmp(name, XATTR_NAME_SELINUX)) {
2973                 /* Not an attribute we recognize, so nothing to do. */
2974                 return;
2975         }
2976
2977         rc = security_context_to_sid_force(value, size, &newsid);
2978         if (rc) {
2979                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2980                        "for (%s, %lu), rc=%d\n",
2981                        inode->i_sb->s_id, inode->i_ino, -rc);
2982                 return;
2983         }
2984
2985         isec->sclass = inode_mode_to_security_class(inode->i_mode);
2986         isec->sid = newsid;
2987         isec->initialized = 1;
2988
2989         return;
2990 }
2991
2992 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2993 {
2994         const struct cred *cred = current_cred();
2995
2996         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2997 }
2998
2999 static int selinux_inode_listxattr(struct dentry *dentry)
3000 {
3001         const struct cred *cred = current_cred();
3002
3003         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3004 }
3005
3006 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3007 {
3008         if (strcmp(name, XATTR_NAME_SELINUX))
3009                 return selinux_inode_setotherxattr(dentry, name);
3010
3011         /* No one is allowed to remove a SELinux security label.
3012            You can change the label, but all data must be labeled. */
3013         return -EACCES;
3014 }
3015
3016 /*
3017  * Copy the inode security context value to the user.
3018  *
3019  * Permission check is handled by selinux_inode_getxattr hook.
3020  */
3021 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
3022 {
3023         u32 size;
3024         int error;
3025         char *context = NULL;
3026         struct inode_security_struct *isec = inode->i_security;
3027
3028         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3029                 return -EOPNOTSUPP;
3030
3031         /*
3032          * If the caller has CAP_MAC_ADMIN, then get the raw context
3033          * value even if it is not defined by current policy; otherwise,
3034          * use the in-core value under current policy.
3035          * Use the non-auditing forms of the permission checks since
3036          * getxattr may be called by unprivileged processes commonly
3037          * and lack of permission just means that we fall back to the
3038          * in-core context value, not a denial.
3039          */
3040         error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3041                                 SECURITY_CAP_NOAUDIT);
3042         if (!error)
3043                 error = security_sid_to_context_force(isec->sid, &context,
3044                                                       &size);
3045         else
3046                 error = security_sid_to_context(isec->sid, &context, &size);
3047         if (error)
3048                 return error;
3049         error = size;
3050         if (alloc) {
3051                 *buffer = context;
3052                 goto out_nofree;
3053         }
3054         kfree(context);
3055 out_nofree:
3056         return error;
3057 }
3058
3059 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3060                                      const void *value, size_t size, int flags)
3061 {
3062         struct inode_security_struct *isec = inode->i_security;
3063         u32 newsid;
3064         int rc;
3065
3066         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3067                 return -EOPNOTSUPP;
3068
3069         if (!value || !size)
3070                 return -EACCES;
3071
3072         rc = security_context_to_sid((void *)value, size, &newsid, GFP_KERNEL);
3073         if (rc)
3074                 return rc;
3075
3076         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3077         isec->sid = newsid;
3078         isec->initialized = 1;
3079         return 0;
3080 }
3081
3082 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3083 {
3084         const int len = sizeof(XATTR_NAME_SELINUX);
3085         if (buffer && len <= buffer_size)
3086                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3087         return len;
3088 }
3089
3090 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
3091 {
3092         struct inode_security_struct *isec = inode->i_security;
3093         *secid = isec->sid;
3094 }
3095
3096 /* file security operations */
3097
3098 static int selinux_revalidate_file_permission(struct file *file, int mask)
3099 {
3100         const struct cred *cred = current_cred();
3101         struct inode *inode = file_inode(file);
3102
3103         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3104         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3105                 mask |= MAY_APPEND;
3106
3107         return file_has_perm(cred, file,
3108                              file_mask_to_av(inode->i_mode, mask));
3109 }
3110
3111 static int selinux_file_permission(struct file *file, int mask)
3112 {
3113         struct inode *inode = file_inode(file);
3114         struct file_security_struct *fsec = file->f_security;
3115         struct inode_security_struct *isec = inode->i_security;
3116         u32 sid = current_sid();
3117
3118         if (!mask)
3119                 /* No permission to check.  Existence test. */
3120                 return 0;
3121
3122         if (sid == fsec->sid && fsec->isid == isec->sid &&
3123             fsec->pseqno == avc_policy_seqno())
3124                 /* No change since file_open check. */
3125                 return 0;
3126
3127         return selinux_revalidate_file_permission(file, mask);
3128 }
3129
3130 static int selinux_file_alloc_security(struct file *file)
3131 {
3132         return file_alloc_security(file);
3133 }
3134
3135 static void selinux_file_free_security(struct file *file)
3136 {
3137         file_free_security(file);
3138 }
3139
3140 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3141                               unsigned long arg)
3142 {
3143         const struct cred *cred = current_cred();
3144         int error = 0;
3145
3146         switch (cmd) {
3147         case FIONREAD:
3148         /* fall through */
3149         case FIBMAP:
3150         /* fall through */
3151         case FIGETBSZ:
3152         /* fall through */
3153         case FS_IOC_GETFLAGS:
3154         /* fall through */
3155         case FS_IOC_GETVERSION:
3156                 error = file_has_perm(cred, file, FILE__GETATTR);
3157                 break;
3158
3159         case FS_IOC_SETFLAGS:
3160         /* fall through */
3161         case FS_IOC_SETVERSION:
3162                 error = file_has_perm(cred, file, FILE__SETATTR);
3163                 break;
3164
3165         /* sys_ioctl() checks */
3166         case FIONBIO:
3167         /* fall through */
3168         case FIOASYNC:
3169                 error = file_has_perm(cred, file, 0);
3170                 break;
3171
3172         case KDSKBENT:
3173         case KDSKBSENT:
3174                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3175                                             SECURITY_CAP_AUDIT);
3176                 break;
3177
3178         /* default case assumes that the command will go
3179          * to the file's ioctl() function.
3180          */
3181         default:
3182                 error = file_has_perm(cred, file, FILE__IOCTL);
3183         }
3184         return error;
3185 }
3186
3187 static int default_noexec;
3188
3189 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3190 {
3191         const struct cred *cred = current_cred();
3192         int rc = 0;
3193
3194         if (default_noexec &&
3195             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3196                 /*
3197                  * We are making executable an anonymous mapping or a
3198                  * private file mapping that will also be writable.
3199                  * This has an additional check.
3200                  */
3201                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3202                 if (rc)
3203                         goto error;
3204         }
3205
3206         if (file) {
3207                 /* read access is always possible with a mapping */
3208                 u32 av = FILE__READ;
3209
3210                 /* write access only matters if the mapping is shared */
3211                 if (shared && (prot & PROT_WRITE))
3212                         av |= FILE__WRITE;
3213
3214                 if (prot & PROT_EXEC)
3215                         av |= FILE__EXECUTE;
3216
3217                 return file_has_perm(cred, file, av);
3218         }
3219
3220 error:
3221         return rc;
3222 }
3223
3224 static int selinux_mmap_addr(unsigned long addr)
3225 {
3226         int rc;
3227
3228         /* do DAC check on address space usage */
3229         rc = cap_mmap_addr(addr);
3230         if (rc)
3231                 return rc;
3232
3233         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3234                 u32 sid = current_sid();
3235                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3236                                   MEMPROTECT__MMAP_ZERO, NULL);
3237         }
3238
3239         return rc;
3240 }
3241
3242 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3243                              unsigned long prot, unsigned long flags)
3244 {
3245         if (selinux_checkreqprot)
3246                 prot = reqprot;
3247
3248         return file_map_prot_check(file, prot,
3249                                    (flags & MAP_TYPE) == MAP_SHARED);
3250 }
3251
3252 static int selinux_file_mprotect(struct vm_area_struct *vma,
3253                                  unsigned long reqprot,
3254                                  unsigned long prot)
3255 {
3256         const struct cred *cred = current_cred();
3257
3258         if (selinux_checkreqprot)
3259                 prot = reqprot;
3260
3261         if (default_noexec &&
3262             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3263                 int rc = 0;
3264                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3265                     vma->vm_end <= vma->vm_mm->brk) {
3266                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3267                 } else if (!vma->vm_file &&
3268                            vma->vm_start <= vma->vm_mm->start_stack &&
3269                            vma->vm_end >= vma->vm_mm->start_stack) {
3270                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3271                 } else if (vma->vm_file && vma->anon_vma) {
3272                         /*
3273                          * We are making executable a file mapping that has
3274                          * had some COW done. Since pages might have been
3275                          * written, check ability to execute the possibly
3276                          * modified content.  This typically should only
3277                          * occur for text relocations.
3278                          */
3279                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3280                 }
3281                 if (rc)
3282                         return rc;
3283         }
3284
3285         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3286 }
3287
3288 static int selinux_file_lock(struct file *file, unsigned int cmd)
3289 {
3290         const struct cred *cred = current_cred();
3291
3292         return file_has_perm(cred, file, FILE__LOCK);
3293 }
3294
3295 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3296                               unsigned long arg)
3297 {
3298         const struct cred *cred = current_cred();
3299         int err = 0;
3300
3301         switch (cmd) {
3302         case F_SETFL:
3303                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3304                         err = file_has_perm(cred, file, FILE__WRITE);
3305                         break;
3306                 }
3307                 /* fall through */
3308         case F_SETOWN:
3309         case F_SETSIG:
3310         case F_GETFL:
3311         case F_GETOWN:
3312         case F_GETSIG:
3313         case F_GETOWNER_UIDS:
3314                 /* Just check FD__USE permission */
3315                 err = file_has_perm(cred, file, 0);
3316                 break;
3317         case F_GETLK:
3318         case F_SETLK:
3319         case F_SETLKW:
3320 #if BITS_PER_LONG == 32
3321         case F_GETLK64:
3322         case F_SETLK64:
3323         case F_SETLKW64:
3324 #endif
3325                 err = file_has_perm(cred, file, FILE__LOCK);
3326                 break;
3327         }
3328
3329         return err;
3330 }
3331
3332 static int selinux_file_set_fowner(struct file *file)
3333 {
3334         struct file_security_struct *fsec;
3335
3336         fsec = file->f_security;
3337         fsec->fown_sid = current_sid();
3338
3339         return 0;
3340 }
3341
3342 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3343                                        struct fown_struct *fown, int signum)
3344 {
3345         struct file *file;
3346         u32 sid = task_sid(tsk);
3347         u32 perm;
3348         struct file_security_struct *fsec;
3349
3350         /* struct fown_struct is never outside the context of a struct file */
3351         file = container_of(fown, struct file, f_owner);
3352
3353         fsec = file->f_security;
3354
3355         if (!signum)
3356                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3357         else
3358                 perm = signal_to_av(signum);
3359
3360         return avc_has_perm(fsec->fown_sid, sid,
3361                             SECCLASS_PROCESS, perm, NULL);
3362 }
3363
3364 static int selinux_file_receive(struct file *file)
3365 {
3366         const struct cred *cred = current_cred();
3367
3368         return file_has_perm(cred, file, file_to_av(file));
3369 }
3370
3371 static int selinux_file_open(struct file *file, const struct cred *cred)
3372 {
3373         struct file_security_struct *fsec;
3374         struct inode_security_struct *isec;
3375
3376         fsec = file->f_security;
3377         isec = file_inode(file)->i_security;
3378         /*
3379          * Save inode label and policy sequence number
3380          * at open-time so that selinux_file_permission
3381          * can determine whether revalidation is necessary.
3382          * Task label is already saved in the file security
3383          * struct as its SID.
3384          */
3385         fsec->isid = isec->sid;
3386         fsec->pseqno = avc_policy_seqno();
3387         /*
3388          * Since the inode label or policy seqno may have changed
3389          * between the selinux_inode_permission check and the saving
3390          * of state above, recheck that access is still permitted.
3391          * Otherwise, access might never be revalidated against the
3392          * new inode label or new policy.
3393          * This check is not redundant - do not remove.
3394          */
3395         return file_path_has_perm(cred, file, open_file_to_av(file));
3396 }
3397
3398 /* task security operations */
3399
3400 static int selinux_task_create(unsigned long clone_flags)
3401 {
3402         return current_has_perm(current, PROCESS__FORK);
3403 }
3404
3405 /*
3406  * allocate the SELinux part of blank credentials
3407  */
3408 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3409 {
3410         struct task_security_struct *tsec;
3411
3412         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3413         if (!tsec)
3414                 return -ENOMEM;
3415
3416         cred->security = tsec;
3417         return 0;
3418 }
3419
3420 /*
3421  * detach and free the LSM part of a set of credentials
3422  */
3423 static void selinux_cred_free(struct cred *cred)
3424 {
3425         struct task_security_struct *tsec = cred->security;
3426
3427         /*
3428          * cred->security == NULL if security_cred_alloc_blank() or
3429          * security_prepare_creds() returned an error.
3430          */
3431         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3432         cred->security = (void *) 0x7UL;
3433         kfree(tsec);
3434 }
3435
3436 /*
3437  * prepare a new set of credentials for modification
3438  */
3439 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3440                                 gfp_t gfp)
3441 {
3442         const struct task_security_struct *old_tsec;
3443         struct task_security_struct *tsec;
3444
3445         old_tsec = old->security;
3446
3447         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3448         if (!tsec)
3449                 return -ENOMEM;
3450
3451         new->security = tsec;
3452         return 0;
3453 }
3454
3455 /*
3456  * transfer the SELinux data to a blank set of creds
3457  */
3458 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3459 {
3460         const struct task_security_struct *old_tsec = old->security;
3461         struct task_security_struct *tsec = new->security;
3462
3463         *tsec = *old_tsec;
3464 }
3465
3466 /*
3467  * set the security data for a kernel service
3468  * - all the creation contexts are set to unlabelled
3469  */
3470 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3471 {
3472         struct task_security_struct *tsec = new->security;
3473         u32 sid = current_sid();
3474         int ret;
3475
3476         ret = avc_has_perm(sid, secid,
3477                            SECCLASS_KERNEL_SERVICE,
3478                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3479                            NULL);
3480         if (ret == 0) {
3481                 tsec->sid = secid;
3482                 tsec->create_sid = 0;
3483                 tsec->keycreate_sid = 0;
3484                 tsec->sockcreate_sid = 0;
3485         }
3486         return ret;
3487 }
3488
3489 /*
3490  * set the file creation context in a security record to the same as the
3491  * objective context of the specified inode
3492  */
3493 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3494 {
3495         struct inode_security_struct *isec = inode->i_security;
3496         struct task_security_struct *tsec = new->security;
3497         u32 sid = current_sid();
3498         int ret;
3499
3500         ret = avc_has_perm(sid, isec->sid,
3501                            SECCLASS_KERNEL_SERVICE,
3502                            KERNEL_SERVICE__CREATE_FILES_AS,
3503                            NULL);
3504
3505         if (ret == 0)
3506                 tsec->create_sid = isec->sid;
3507         return ret;
3508 }
3509
3510 static int selinux_kernel_module_request(char *kmod_name)
3511 {
3512         u32 sid;
3513         struct common_audit_data ad;
3514
3515         sid = task_sid(current);
3516
3517         ad.type = LSM_AUDIT_DATA_KMOD;
3518         ad.u.kmod_name = kmod_name;
3519
3520         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3521                             SYSTEM__MODULE_REQUEST, &ad);
3522 }
3523
3524 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3525 {
3526         return current_has_perm(p, PROCESS__SETPGID);
3527 }
3528
3529 static int selinux_task_getpgid(struct task_struct *p)
3530 {
3531         return current_has_perm(p, PROCESS__GETPGID);
3532 }
3533
3534 static int selinux_task_getsid(struct task_struct *p)
3535 {
3536         return current_has_perm(p, PROCESS__GETSESSION);
3537 }
3538
3539 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3540 {
3541         *secid = task_sid(p);
3542 }
3543
3544 static int selinux_task_setnice(struct task_struct *p, int nice)
3545 {
3546         int rc;
3547
3548         rc = cap_task_setnice(p, nice);
3549         if (rc)
3550                 return rc;
3551
3552         return current_has_perm(p, PROCESS__SETSCHED);
3553 }
3554
3555 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3556 {
3557         int rc;
3558
3559         rc = cap_task_setioprio(p, ioprio);
3560         if (rc)
3561                 return rc;
3562
3563         return current_has_perm(p, PROCESS__SETSCHED);
3564 }
3565
3566 static int selinux_task_getioprio(struct task_struct *p)
3567 {
3568         return current_has_perm(p, PROCESS__GETSCHED);
3569 }
3570
3571 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3572                 struct rlimit *new_rlim)
3573 {
3574         struct rlimit *old_rlim = p->signal->rlim + resource;
3575
3576         /* Control the ability to change the hard limit (whether
3577            lowering or raising it), so that the hard limit can
3578            later be used as a safe reset point for the soft limit
3579            upon context transitions.  See selinux_bprm_committing_creds. */
3580         if (old_rlim->rlim_max != new_rlim->rlim_max)
3581                 return current_has_perm(p, PROCESS__SETRLIMIT);
3582
3583         return 0;
3584 }
3585
3586 static int selinux_task_setscheduler(struct task_struct *p)
3587 {
3588         int rc;
3589
3590         rc = cap_task_setscheduler(p);
3591         if (rc)
3592                 return rc;
3593
3594         return current_has_perm(p, PROCESS__SETSCHED);
3595 }
3596
3597 static int selinux_task_getscheduler(struct task_struct *p)
3598 {
3599         return current_has_perm(p, PROCESS__GETSCHED);
3600 }
3601
3602 static int selinux_task_movememory(struct task_struct *p)
3603 {
3604         return current_has_perm(p, PROCESS__SETSCHED);
3605 }
3606
3607 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3608                                 int sig, u32 secid)
3609 {
3610         u32 perm;
3611         int rc;
3612
3613         if (!sig)
3614                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3615         else
3616                 perm = signal_to_av(sig);
3617         if (secid)
3618                 rc = avc_has_perm(secid, task_sid(p),
3619                                   SECCLASS_PROCESS, perm, NULL);
3620         else
3621                 rc = current_has_perm(p, perm);
3622         return rc;
3623 }
3624
3625 static int selinux_task_wait(struct task_struct *p)
3626 {
3627         return task_has_perm(p, current, PROCESS__SIGCHLD);
3628 }
3629
3630 static void selinux_task_to_inode(struct task_struct *p,
3631                                   struct inode *inode)
3632 {
3633         struct inode_security_struct *isec = inode->i_security;
3634         u32 sid = task_sid(p);
3635
3636         isec->sid = sid;
3637         isec->initialized = 1;
3638 }
3639
3640 /* Returns error only if unable to parse addresses */
3641 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3642                         struct common_audit_data *ad, u8 *proto)
3643 {
3644         int offset, ihlen, ret = -EINVAL;
3645         struct iphdr _iph, *ih;
3646
3647         offset = skb_network_offset(skb);
3648         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3649         if (ih == NULL)
3650                 goto out;
3651
3652         ihlen = ih->ihl * 4;
3653         if (ihlen < sizeof(_iph))
3654                 goto out;
3655
3656         ad->u.net->v4info.saddr = ih->saddr;
3657         ad->u.net->v4info.daddr = ih->daddr;
3658         ret = 0;
3659
3660         if (proto)
3661                 *proto = ih->protocol;
3662
3663         switch (ih->protocol) {
3664         case IPPROTO_TCP: {
3665                 struct tcphdr _tcph, *th;
3666
3667                 if (ntohs(ih->frag_off) & IP_OFFSET)
3668                         break;
3669
3670                 offset += ihlen;
3671                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3672                 if (th == NULL)
3673                         break;
3674
3675                 ad->u.net->sport = th->source;
3676                 ad->u.net->dport = th->dest;
3677                 break;
3678         }
3679
3680         case IPPROTO_UDP: {
3681                 struct udphdr _udph, *uh;
3682
3683                 if (ntohs(ih->frag_off) & IP_OFFSET)
3684                         break;
3685
3686                 offset += ihlen;
3687                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3688                 if (uh == NULL)
3689                         break;
3690
3691                 ad->u.net->sport = uh->source;
3692                 ad->u.net->dport = uh->dest;
3693                 break;
3694         }
3695
3696         case IPPROTO_DCCP: {
3697                 struct dccp_hdr _dccph, *dh;
3698
3699                 if (ntohs(ih->frag_off) & IP_OFFSET)
3700                         break;
3701
3702                 offset += ihlen;
3703                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3704                 if (dh == NULL)
3705                         break;
3706
3707                 ad->u.net->sport = dh->dccph_sport;
3708                 ad->u.net->dport = dh->dccph_dport;
3709                 break;
3710         }
3711
3712         default:
3713                 break;
3714         }
3715 out:
3716         return ret;
3717 }
3718
3719 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3720
3721 /* Returns error only if unable to parse addresses */
3722 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3723                         struct common_audit_data *ad, u8 *proto)
3724 {
3725         u8 nexthdr;
3726         int ret = -EINVAL, offset;
3727         struct ipv6hdr _ipv6h, *ip6;
3728         __be16 frag_off;
3729
3730         offset = skb_network_offset(skb);
3731         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3732         if (ip6 == NULL)
3733                 goto out;
3734
3735         ad->u.net->v6info.saddr = ip6->saddr;
3736         ad->u.net->v6info.daddr = ip6->daddr;
3737         ret = 0;
3738
3739         nexthdr = ip6->nexthdr;
3740         offset += sizeof(_ipv6h);
3741         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3742         if (offset < 0)
3743                 goto out;
3744
3745         if (proto)
3746                 *proto = nexthdr;
3747
3748         switch (nexthdr) {
3749         case IPPROTO_TCP: {
3750                 struct tcphdr _tcph, *th;
3751
3752                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3753                 if (th == NULL)
3754                         break;
3755
3756                 ad->u.net->sport = th->source;
3757                 ad->u.net->dport = th->dest;
3758                 break;
3759         }
3760
3761         case IPPROTO_UDP: {
3762                 struct udphdr _udph, *uh;
3763
3764                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3765                 if (uh == NULL)
3766                         break;
3767
3768                 ad->u.net->sport = uh->source;
3769                 ad->u.net->dport = uh->dest;
3770                 break;
3771         }
3772
3773         case IPPROTO_DCCP: {
3774                 struct dccp_hdr _dccph, *dh;
3775
3776                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3777                 if (dh == NULL)
3778                         break;
3779
3780                 ad->u.net->sport = dh->dccph_sport;
3781                 ad->u.net->dport = dh->dccph_dport;
3782                 break;
3783         }
3784
3785         /* includes fragments */
3786         default:
3787                 break;
3788         }
3789 out:
3790         return ret;
3791 }
3792
3793 #endif /* IPV6 */
3794
3795 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3796                              char **_addrp, int src, u8 *proto)
3797 {
3798         char *addrp;
3799         int ret;
3800
3801         switch (ad->u.net->family) {
3802         case PF_INET:
3803                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3804                 if (ret)
3805                         goto parse_error;
3806                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
3807                                        &ad->u.net->v4info.daddr);
3808                 goto okay;
3809
3810 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3811         case PF_INET6:
3812                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3813                 if (ret)
3814                         goto parse_error;
3815                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
3816                                        &ad->u.net->v6info.daddr);
3817                 goto okay;
3818 #endif  /* IPV6 */
3819         default:
3820                 addrp = NULL;
3821                 goto okay;
3822         }
3823
3824 parse_error:
3825         printk(KERN_WARNING
3826                "SELinux: failure in selinux_parse_skb(),"
3827                " unable to parse packet\n");
3828         return ret;
3829
3830 okay:
3831         if (_addrp)
3832                 *_addrp = addrp;
3833         return 0;
3834 }
3835
3836 /**
3837  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3838  * @skb: the packet
3839  * @family: protocol family
3840  * @sid: the packet's peer label SID
3841  *
3842  * Description:
3843  * Check the various different forms of network peer labeling and determine
3844  * the peer label/SID for the packet; most of the magic actually occurs in
3845  * the security server function security_net_peersid_cmp().  The function
3846  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3847  * or -EACCES if @sid is invalid due to inconsistencies with the different
3848  * peer labels.
3849  *
3850  */
3851 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3852 {
3853         int err;
3854         u32 xfrm_sid;
3855         u32 nlbl_sid;
3856         u32 nlbl_type;
3857
3858         err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
3859         if (unlikely(err))
3860                 return -EACCES;
3861         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3862         if (unlikely(err))
3863                 return -EACCES;
3864
3865         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3866         if (unlikely(err)) {
3867                 printk(KERN_WARNING
3868                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3869                        " unable to determine packet's peer label\n");
3870                 return -EACCES;
3871         }
3872
3873         return 0;
3874 }
3875
3876 /**
3877  * selinux_conn_sid - Determine the child socket label for a connection
3878  * @sk_sid: the parent socket's SID
3879  * @skb_sid: the packet's SID
3880  * @conn_sid: the resulting connection SID
3881  *
3882  * If @skb_sid is valid then the user:role:type information from @sk_sid is
3883  * combined with the MLS information from @skb_sid in order to create
3884  * @conn_sid.  If @skb_sid is not valid then then @conn_sid is simply a copy
3885  * of @sk_sid.  Returns zero on success, negative values on failure.
3886  *
3887  */
3888 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
3889 {
3890         int err = 0;
3891
3892         if (skb_sid != SECSID_NULL)
3893                 err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid);
3894         else
3895                 *conn_sid = sk_sid;
3896
3897         return err;
3898 }
3899
3900 /* socket security operations */
3901
3902 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3903                                  u16 secclass, u32 *socksid)
3904 {
3905         if (tsec->sockcreate_sid > SECSID_NULL) {
3906                 *socksid = tsec->sockcreate_sid;
3907                 return 0;
3908         }
3909
3910         return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3911                                        socksid);
3912 }
3913
3914 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3915 {
3916         struct sk_security_struct *sksec = sk->sk_security;
3917         struct common_audit_data ad;
3918         struct lsm_network_audit net = {0,};
3919         u32 tsid = task_sid(task);
3920
3921         if (sksec->sid == SECINITSID_KERNEL)
3922                 return 0;
3923
3924         ad.type = LSM_AUDIT_DATA_NET;
3925         ad.u.net = &net;
3926         ad.u.net->sk = sk;
3927
3928         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3929 }
3930
3931 static int selinux_socket_create(int family, int type,
3932                                  int protocol, int kern)
3933 {
3934         const struct task_security_struct *tsec = current_security();
3935         u32 newsid;
3936         u16 secclass;
3937         int rc;
3938
3939         if (kern)
3940                 return 0;
3941
3942         secclass = socket_type_to_security_class(family, type, protocol);
3943         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3944         if (rc)
3945                 return rc;
3946
3947         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3948 }
3949
3950 static int selinux_socket_post_create(struct socket *sock, int family,
3951                                       int type, int protocol, int kern)
3952 {
3953         const struct task_security_struct *tsec = current_security();
3954         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3955         struct sk_security_struct *sksec;
3956         int err = 0;
3957
3958         isec->sclass = socket_type_to_security_class(family, type, protocol);
3959
3960         if (kern)
3961                 isec->sid = SECINITSID_KERNEL;
3962         else {
3963                 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3964                 if (err)
3965                         return err;
3966         }
3967
3968         isec->initialized = 1;
3969
3970         if (sock->sk) {
3971                 sksec = sock->sk->sk_security;
3972                 sksec->sid = isec->sid;
3973                 sksec->sclass = isec->sclass;
3974                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3975         }
3976
3977         return err;
3978 }
3979
3980 /* Range of port numbers used to automatically bind.
3981    Need to determine whether we should perform a name_bind
3982    permission check between the socket and the port number. */
3983
3984 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3985 {
3986         struct sock *sk = sock->sk;
3987         u16 family;
3988         int err;
3989
3990         err = sock_has_perm(current, sk, SOCKET__BIND);
3991         if (err)
3992                 goto out;
3993
3994         /*
3995          * If PF_INET or PF_INET6, check name_bind permission for the port.
3996          * Multiple address binding for SCTP is not supported yet: we just
3997          * check the first address now.
3998          */
3999         family = sk->sk_family;
4000         if (family == PF_INET || family == PF_INET6) {
4001                 char *addrp;
4002                 struct sk_security_struct *sksec = sk->sk_security;
4003                 struct common_audit_data ad;
4004                 struct lsm_network_audit net = {0,};
4005                 struct sockaddr_in *addr4 = NULL;
4006                 struct sockaddr_in6 *addr6 = NULL;
4007                 unsigned short snum;
4008                 u32 sid, node_perm;
4009
4010                 if (family == PF_INET) {
4011                         addr4 = (struct sockaddr_in *)address;
4012                         snum = ntohs(addr4->sin_port);
4013                         addrp = (char *)&addr4->sin_addr.s_addr;
4014                 } else {
4015                         addr6 = (struct sockaddr_in6 *)address;
4016                         snum = ntohs(addr6->sin6_port);
4017                         addrp = (char *)&addr6->sin6_addr.s6_addr;
4018                 }
4019
4020                 if (snum) {
4021                         int low, high;
4022
4023                         inet_get_local_port_range(sock_net(sk), &low, &high);
4024
4025                         if (snum < max(PROT_SOCK, low) || snum > high) {
4026                                 err = sel_netport_sid(sk->sk_protocol,
4027                                                       snum, &sid);
4028                                 if (err)
4029                                         goto out;
4030                                 ad.type = LSM_AUDIT_DATA_NET;
4031                                 ad.u.net = &net;
4032                                 ad.u.net->sport = htons(snum);
4033                                 ad.u.net->family = family;
4034                                 err = avc_has_perm(sksec->sid, sid,
4035                                                    sksec->sclass,
4036                                                    SOCKET__NAME_BIND, &ad);
4037                                 if (err)
4038                                         goto out;
4039                         }
4040                 }
4041
4042                 switch (sksec->sclass) {
4043                 case SECCLASS_TCP_SOCKET:
4044                         node_perm = TCP_SOCKET__NODE_BIND;
4045                         break;
4046
4047                 case SECCLASS_UDP_SOCKET:
4048                         node_perm = UDP_SOCKET__NODE_BIND;
4049                         break;
4050
4051                 case SECCLASS_DCCP_SOCKET:
4052                         node_perm = DCCP_SOCKET__NODE_BIND;
4053                         break;
4054
4055                 default:
4056                         node_perm = RAWIP_SOCKET__NODE_BIND;
4057                         break;
4058                 }
4059
4060                 err = sel_netnode_sid(addrp, family, &sid);
4061                 if (err)
4062                         goto out;
4063
4064                 ad.type = LSM_AUDIT_DATA_NET;
4065                 ad.u.net = &net;
4066                 ad.u.net->sport = htons(snum);
4067                 ad.u.net->family = family;
4068
4069                 if (family == PF_INET)
4070                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4071                 else
4072                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4073
4074                 err = avc_has_perm(sksec->sid, sid,
4075                                    sksec->sclass, node_perm, &ad);
4076                 if (err)
4077                         goto out;
4078         }
4079 out:
4080         return err;
4081 }
4082
4083 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
4084 {
4085         struct sock *sk = sock->sk;
4086         struct sk_security_struct *sksec = sk->sk_security;
4087         int err;
4088
4089         err = sock_has_perm(current, sk, SOCKET__CONNECT);
4090         if (err)
4091                 return err;
4092
4093         /*
4094          * If a TCP or DCCP socket, check name_connect permission for the port.
4095          */
4096         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4097             sksec->sclass == SECCLASS_DCCP_SOCKET) {
4098                 struct common_audit_data ad;
4099                 struct lsm_network_audit net = {0,};
4100                 struct sockaddr_in *addr4 = NULL;
4101                 struct sockaddr_in6 *addr6 = NULL;
4102                 unsigned short snum;
4103                 u32 sid, perm;
4104
4105                 if (sk->sk_family == PF_INET) {
4106                         addr4 = (struct sockaddr_in *)address;
4107                         if (addrlen < sizeof(struct sockaddr_in))
4108                                 return -EINVAL;
4109                         snum = ntohs(addr4->sin_port);
4110                 } else {
4111                         addr6 = (struct sockaddr_in6 *)address;
4112                         if (addrlen < SIN6_LEN_RFC2133)
4113                                 return -EINVAL;
4114                         snum = ntohs(addr6->sin6_port);
4115                 }
4116
4117                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4118                 if (err)
4119                         goto out;
4120
4121                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
4122                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
4123
4124                 ad.type = LSM_AUDIT_DATA_NET;
4125                 ad.u.net = &net;
4126                 ad.u.net->dport = htons(snum);
4127                 ad.u.net->family = sk->sk_family;
4128                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4129                 if (err)
4130                         goto out;
4131         }
4132
4133         err = selinux_netlbl_socket_connect(sk, address);
4134
4135 out:
4136         return err;
4137 }
4138
4139 static int selinux_socket_listen(struct socket *sock, int backlog)
4140 {
4141         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
4142 }
4143
4144 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4145 {
4146         int err;
4147         struct inode_security_struct *isec;
4148         struct inode_security_struct *newisec;
4149
4150         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4151         if (err)
4152                 return err;
4153
4154         newisec = SOCK_INODE(newsock)->i_security;
4155
4156         isec = SOCK_INODE(sock)->i_security;
4157         newisec->sclass = isec->sclass;
4158         newisec->sid = isec->sid;
4159         newisec->initialized = 1;
4160
4161         return 0;
4162 }
4163
4164 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4165                                   int size)
4166 {
4167         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4168 }
4169
4170 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4171                                   int size, int flags)
4172 {
4173         return sock_has_perm(current, sock->sk, SOCKET__READ);
4174 }
4175
4176 static int selinux_socket_getsockname(struct socket *sock)
4177 {
4178         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4179 }
4180
4181 static int selinux_socket_getpeername(struct socket *sock)
4182 {
4183         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4184 }
4185
4186 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4187 {
4188         int err;
4189
4190         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4191         if (err)
4192                 return err;
4193
4194         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4195 }
4196
4197 static int selinux_socket_getsockopt(struct socket *sock, int level,
4198                                      int optname)
4199 {
4200         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4201 }
4202
4203 static int selinux_socket_shutdown(struct socket *sock, int how)
4204 {
4205         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4206 }
4207
4208 static int selinux_socket_unix_stream_connect(struct sock *sock,
4209                                               struct sock *other,
4210                                               struct sock *newsk)
4211 {
4212         struct sk_security_struct *sksec_sock = sock->sk_security;
4213         struct sk_security_struct *sksec_other = other->sk_security;
4214         struct sk_security_struct *sksec_new = newsk->sk_security;
4215         struct common_audit_data ad;
4216         struct lsm_network_audit net = {0,};
4217         int err;
4218
4219         ad.type = LSM_AUDIT_DATA_NET;
4220         ad.u.net = &net;
4221         ad.u.net->sk = other;
4222
4223         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4224                            sksec_other->sclass,
4225                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4226         if (err)
4227                 return err;
4228
4229         /* server child socket */
4230         sksec_new->peer_sid = sksec_sock->sid;
4231         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4232                                     &sksec_new->sid);
4233         if (err)
4234                 return err;
4235
4236         /* connecting socket */
4237         sksec_sock->peer_sid = sksec_new->sid;
4238
4239         return 0;
4240 }
4241
4242 static int selinux_socket_unix_may_send(struct socket *sock,
4243                                         struct socket *other)
4244 {
4245         struct sk_security_struct *ssec = sock->sk->sk_security;
4246         struct sk_security_struct *osec = other->sk->sk_security;
4247         struct common_audit_data ad;
4248         struct lsm_network_audit net = {0,};
4249
4250         ad.type = LSM_AUDIT_DATA_NET;
4251         ad.u.net = &net;
4252         ad.u.net->sk = other->sk;
4253
4254         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4255                             &ad);
4256 }
4257
4258 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4259                                     u32 peer_sid,
4260                                     struct common_audit_data *ad)
4261 {
4262         int err;
4263         u32 if_sid;
4264         u32 node_sid;
4265
4266         err = sel_netif_sid(ifindex, &if_sid);
4267         if (err)
4268                 return err;
4269         err = avc_has_perm(peer_sid, if_sid,
4270                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4271         if (err)
4272                 return err;
4273
4274         err = sel_netnode_sid(addrp, family, &node_sid);
4275         if (err)
4276                 return err;
4277         return avc_has_perm(peer_sid, node_sid,
4278                             SECCLASS_NODE, NODE__RECVFROM, ad);
4279 }
4280
4281 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4282                                        u16 family)
4283 {
4284         int err = 0;
4285         struct sk_security_struct *sksec = sk->sk_security;
4286         u32 sk_sid = sksec->sid;
4287         struct common_audit_data ad;
4288         struct lsm_network_audit net = {0,};
4289         char *addrp;
4290
4291         ad.type = LSM_AUDIT_DATA_NET;
4292         ad.u.net = &net;
4293         ad.u.net->netif = skb->skb_iif;
4294         ad.u.net->family = family;
4295         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4296         if (err)
4297                 return err;
4298
4299         if (selinux_secmark_enabled()) {
4300                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4301                                    PACKET__RECV, &ad);
4302                 if (err)
4303                         return err;
4304         }
4305
4306         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4307         if (err)
4308                 return err;
4309         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4310
4311         return err;
4312 }
4313
4314 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4315 {
4316         int err;
4317         struct sk_security_struct *sksec = sk->sk_security;
4318         u16 family = sk->sk_family;
4319         u32 sk_sid = sksec->sid;
4320         struct common_audit_data ad;
4321         struct lsm_network_audit net = {0,};
4322         char *addrp;
4323         u8 secmark_active;
4324         u8 peerlbl_active;
4325
4326         if (family != PF_INET && family != PF_INET6)
4327                 return 0;
4328
4329         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4330         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4331                 family = PF_INET;
4332
4333         /* If any sort of compatibility mode is enabled then handoff processing
4334          * to the selinux_sock_rcv_skb_compat() function to deal with the
4335          * special handling.  We do this in an attempt to keep this function
4336          * as fast and as clean as possible. */
4337         if (!selinux_policycap_netpeer)
4338                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4339
4340         secmark_active = selinux_secmark_enabled();
4341         peerlbl_active = selinux_peerlbl_enabled();
4342         if (!secmark_active && !peerlbl_active)
4343                 return 0;
4344
4345         ad.type = LSM_AUDIT_DATA_NET;
4346         ad.u.net = &net;
4347         ad.u.net->netif = skb->skb_iif;
4348         ad.u.net->family = family;
4349         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4350         if (err)
4351                 return err;
4352
4353         if (peerlbl_active) {
4354                 u32 peer_sid;
4355
4356                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4357                 if (err)
4358                         return err;
4359                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4360                                                peer_sid, &ad);
4361                 if (err) {
4362                         selinux_netlbl_err(skb, err, 0);
4363                         return err;
4364                 }
4365                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4366                                    PEER__RECV, &ad);
4367                 if (err) {
4368                         selinux_netlbl_err(skb, err, 0);
4369                         return err;
4370                 }
4371         }
4372
4373         if (secmark_active) {
4374                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4375                                    PACKET__RECV, &ad);
4376                 if (err)
4377                         return err;
4378         }
4379
4380         return err;
4381 }
4382
4383 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4384                                             int __user *optlen, unsigned len)
4385 {
4386         int err = 0;
4387         char *scontext;
4388         u32 scontext_len;
4389         struct sk_security_struct *sksec = sock->sk->sk_security;
4390         u32 peer_sid = SECSID_NULL;
4391
4392         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4393             sksec->sclass == SECCLASS_TCP_SOCKET)
4394                 peer_sid = sksec->peer_sid;
4395         if (peer_sid == SECSID_NULL)
4396                 return -ENOPROTOOPT;
4397
4398         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4399         if (err)
4400                 return err;
4401
4402         if (scontext_len > len) {
4403                 err = -ERANGE;
4404                 goto out_len;
4405         }
4406
4407         if (copy_to_user(optval, scontext, scontext_len))
4408                 err = -EFAULT;
4409
4410 out_len:
4411         if (put_user(scontext_len, optlen))
4412                 err = -EFAULT;
4413         kfree(scontext);
4414         return err;
4415 }
4416
4417 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4418 {
4419         u32 peer_secid = SECSID_NULL;
4420         u16 family;
4421
4422         if (skb && skb->protocol == htons(ETH_P_IP))
4423                 family = PF_INET;
4424         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4425                 family = PF_INET6;
4426         else if (sock)
4427                 family = sock->sk->sk_family;
4428         else
4429                 goto out;
4430
4431         if (sock && family == PF_UNIX)
4432                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4433         else if (skb)
4434                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4435
4436 out:
4437         *secid = peer_secid;
4438         if (peer_secid == SECSID_NULL)
4439                 return -EINVAL;
4440         return 0;
4441 }
4442
4443 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4444 {
4445         struct sk_security_struct *sksec;
4446
4447         sksec = kzalloc(sizeof(*sksec), priority);
4448         if (!sksec)
4449                 return -ENOMEM;
4450
4451         sksec->peer_sid = SECINITSID_UNLABELED;
4452         sksec->sid = SECINITSID_UNLABELED;
4453         selinux_netlbl_sk_security_reset(sksec);
4454         sk->sk_security = sksec;
4455
4456         return 0;
4457 }
4458
4459 static void selinux_sk_free_security(struct sock *sk)
4460 {
4461         struct sk_security_struct *sksec = sk->sk_security;
4462
4463         sk->sk_security = NULL;
4464         selinux_netlbl_sk_security_free(sksec);
4465         kfree(sksec);
4466 }
4467
4468 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4469 {
4470         struct sk_security_struct *sksec = sk->sk_security;
4471         struct sk_security_struct *newsksec = newsk->sk_security;
4472
4473         newsksec->sid = sksec->sid;
4474         newsksec->peer_sid = sksec->peer_sid;
4475         newsksec->sclass = sksec->sclass;
4476
4477         selinux_netlbl_sk_security_reset(newsksec);
4478 }
4479
4480 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4481 {
4482         if (!sk)
4483                 *secid = SECINITSID_ANY_SOCKET;
4484         else {
4485                 struct sk_security_struct *sksec = sk->sk_security;
4486
4487                 *secid = sksec->sid;
4488         }
4489 }
4490
4491 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4492 {
4493         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4494         struct sk_security_struct *sksec = sk->sk_security;
4495
4496         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4497             sk->sk_family == PF_UNIX)
4498                 isec->sid = sksec->sid;
4499         sksec->sclass = isec->sclass;
4500 }
4501
4502 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4503                                      struct request_sock *req)
4504 {
4505         struct sk_security_struct *sksec = sk->sk_security;
4506         int err;
4507         u16 family = req->rsk_ops->family;
4508         u32 connsid;
4509         u32 peersid;
4510
4511         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4512         if (err)
4513                 return err;
4514         err = selinux_conn_sid(sksec->sid, peersid, &connsid);
4515         if (err)
4516                 return err;
4517         req->secid = connsid;
4518         req->peer_secid = peersid;
4519
4520         return selinux_netlbl_inet_conn_request(req, family);
4521 }
4522
4523 static void selinux_inet_csk_clone(struct sock *newsk,
4524                                    const struct request_sock *req)
4525 {
4526         struct sk_security_struct *newsksec = newsk->sk_security;
4527
4528         newsksec->sid = req->secid;
4529         newsksec->peer_sid = req->peer_secid;
4530         /* NOTE: Ideally, we should also get the isec->sid for the
4531            new socket in sync, but we don't have the isec available yet.
4532            So we will wait until sock_graft to do it, by which
4533            time it will have been created and available. */
4534
4535         /* We don't need to take any sort of lock here as we are the only
4536          * thread with access to newsksec */
4537         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4538 }
4539
4540 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4541 {
4542         u16 family = sk->sk_family;
4543         struct sk_security_struct *sksec = sk->sk_security;
4544
4545         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4546         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4547                 family = PF_INET;
4548
4549         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4550 }
4551
4552 static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
4553 {
4554         skb_set_owner_w(skb, sk);
4555 }
4556
4557 static int selinux_secmark_relabel_packet(u32 sid)
4558 {
4559         const struct task_security_struct *__tsec;
4560         u32 tsid;
4561
4562         __tsec = current_security();
4563         tsid = __tsec->sid;
4564
4565         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4566 }
4567
4568 static void selinux_secmark_refcount_inc(void)
4569 {
4570         atomic_inc(&selinux_secmark_refcount);
4571 }
4572
4573 static void selinux_secmark_refcount_dec(void)
4574 {
4575         atomic_dec(&selinux_secmark_refcount);
4576 }
4577
4578 static void selinux_req_classify_flow(const struct request_sock *req,
4579                                       struct flowi *fl)
4580 {
4581         fl->flowi_secid = req->secid;
4582 }
4583
4584 static int selinux_tun_dev_alloc_security(void **security)
4585 {
4586         struct tun_security_struct *tunsec;
4587
4588         tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
4589         if (!tunsec)
4590                 return -ENOMEM;
4591         tunsec->sid = current_sid();
4592
4593         *security = tunsec;
4594         return 0;
4595 }
4596
4597 static void selinux_tun_dev_free_security(void *security)
4598 {
4599         kfree(security);
4600 }
4601
4602 static int selinux_tun_dev_create(void)
4603 {
4604         u32 sid = current_sid();
4605
4606         /* we aren't taking into account the "sockcreate" SID since the socket
4607          * that is being created here is not a socket in the traditional sense,
4608          * instead it is a private sock, accessible only to the kernel, and
4609          * representing a wide range of network traffic spanning multiple
4610          * connections unlike traditional sockets - check the TUN driver to
4611          * get a better understanding of why this socket is special */
4612
4613         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4614                             NULL);
4615 }
4616
4617 static int selinux_tun_dev_attach_queue(void *security)
4618 {
4619         struct tun_security_struct *tunsec = security;
4620
4621         return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
4622                             TUN_SOCKET__ATTACH_QUEUE, NULL);
4623 }
4624
4625 static int selinux_tun_dev_attach(struct sock *sk, void *security)
4626 {
4627         struct tun_security_struct *tunsec = security;
4628         struct sk_security_struct *sksec = sk->sk_security;
4629
4630         /* we don't currently perform any NetLabel based labeling here and it
4631          * isn't clear that we would want to do so anyway; while we could apply
4632          * labeling without the support of the TUN user the resulting labeled
4633          * traffic from the other end of the connection would almost certainly
4634          * cause confusion to the TUN user that had no idea network labeling
4635          * protocols were being used */
4636
4637         sksec->sid = tunsec->sid;
4638         sksec->sclass = SECCLASS_TUN_SOCKET;
4639
4640         return 0;
4641 }
4642
4643 static int selinux_tun_dev_open(void *security)
4644 {
4645         struct tun_security_struct *tunsec = security;
4646         u32 sid = current_sid();
4647         int err;
4648
4649         err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4650                            TUN_SOCKET__RELABELFROM, NULL);
4651         if (err)
4652                 return err;
4653         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4654                            TUN_SOCKET__RELABELTO, NULL);
4655         if (err)
4656                 return err;
4657         tunsec->sid = sid;
4658
4659         return 0;
4660 }
4661
4662 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4663 {
4664         int err = 0;
4665         u32 perm;
4666         struct nlmsghdr *nlh;
4667         struct sk_security_struct *sksec = sk->sk_security;
4668
4669         if (skb->len < NLMSG_HDRLEN) {
4670                 err = -EINVAL;
4671                 goto out;
4672         }
4673         nlh = nlmsg_hdr(skb);
4674
4675         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4676         if (err) {
4677                 if (err == -EINVAL) {
4678                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4679                                   "SELinux:  unrecognized netlink message"
4680                                   " type=%hu for sclass=%hu\n",
4681                                   nlh->nlmsg_type, sksec->sclass);
4682                         if (!selinux_enforcing || security_get_allow_unknown())
4683                                 err = 0;
4684                 }
4685
4686                 /* Ignore */
4687                 if (err == -ENOENT)
4688                         err = 0;
4689                 goto out;
4690         }
4691
4692         err = sock_has_perm(current, sk, perm);
4693 out:
4694         return err;
4695 }
4696
4697 #ifdef CONFIG_NETFILTER
4698
4699 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4700                                        u16 family)
4701 {
4702         int err;
4703         char *addrp;
4704         u32 peer_sid;
4705         struct common_audit_data ad;
4706         struct lsm_network_audit net = {0,};
4707         u8 secmark_active;
4708         u8 netlbl_active;
4709         u8 peerlbl_active;
4710
4711         if (!selinux_policycap_netpeer)
4712                 return NF_ACCEPT;
4713
4714         secmark_active = selinux_secmark_enabled();
4715         netlbl_active = netlbl_enabled();
4716         peerlbl_active = selinux_peerlbl_enabled();
4717         if (!secmark_active && !peerlbl_active)
4718                 return NF_ACCEPT;
4719
4720         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4721                 return NF_DROP;
4722
4723         ad.type = LSM_AUDIT_DATA_NET;
4724         ad.u.net = &net;
4725         ad.u.net->netif = ifindex;
4726         ad.u.net->family = family;
4727         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4728                 return NF_DROP;
4729
4730         if (peerlbl_active) {
4731                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4732                                                peer_sid, &ad);
4733                 if (err) {
4734                         selinux_netlbl_err(skb, err, 1);
4735                         return NF_DROP;
4736                 }
4737         }
4738
4739         if (secmark_active)
4740                 if (avc_has_perm(peer_sid, skb->secmark,
4741                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4742                         return NF_DROP;
4743
4744         if (netlbl_active)
4745                 /* we do this in the FORWARD path and not the POST_ROUTING
4746                  * path because we want to make sure we apply the necessary
4747                  * labeling before IPsec is applied so we can leverage AH
4748                  * protection */
4749                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4750                         return NF_DROP;
4751
4752         return NF_ACCEPT;
4753 }
4754
4755 static unsigned int selinux_ipv4_forward(const struct nf_hook_ops *ops,
4756                                          struct sk_buff *skb,
4757                                          const struct net_device *in,
4758                                          const struct net_device *out,
4759                                          int (*okfn)(struct sk_buff *))
4760 {
4761         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4762 }
4763
4764 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4765 static unsigned int selinux_ipv6_forward(const struct nf_hook_ops *ops,
4766                                          struct sk_buff *skb,
4767                                          const struct net_device *in,
4768                                          const struct net_device *out,
4769                                          int (*okfn)(struct sk_buff *))
4770 {
4771         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4772 }
4773 #endif  /* IPV6 */
4774
4775 static unsigned int selinux_ip_output(struct sk_buff *skb,
4776                                       u16 family)
4777 {
4778         struct sock *sk;
4779         u32 sid;
4780
4781         if (!netlbl_enabled())
4782                 return NF_ACCEPT;
4783
4784         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4785          * because we want to make sure we apply the necessary labeling
4786          * before IPsec is applied so we can leverage AH protection */
4787         sk = skb->sk;
4788         if (sk) {
4789                 struct sk_security_struct *sksec;
4790
4791                 if (sk->sk_state == TCP_LISTEN)
4792                         /* if the socket is the listening state then this
4793                          * packet is a SYN-ACK packet which means it needs to
4794                          * be labeled based on the connection/request_sock and
4795                          * not the parent socket.  unfortunately, we can't
4796                          * lookup the request_sock yet as it isn't queued on
4797                          * the parent socket until after the SYN-ACK is sent.
4798                          * the "solution" is to simply pass the packet as-is
4799                          * as any IP option based labeling should be copied
4800                          * from the initial connection request (in the IP
4801                          * layer).  it is far from ideal, but until we get a
4802                          * security label in the packet itself this is the
4803                          * best we can do. */
4804                         return NF_ACCEPT;
4805
4806                 /* standard practice, label using the parent socket */
4807                 sksec = sk->sk_security;
4808                 sid = sksec->sid;
4809         } else
4810                 sid = SECINITSID_KERNEL;
4811         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4812                 return NF_DROP;
4813
4814         return NF_ACCEPT;
4815 }
4816
4817 static unsigned int selinux_ipv4_output(const struct nf_hook_ops *ops,
4818                                         struct sk_buff *skb,
4819                                         const struct net_device *in,
4820                                         const struct net_device *out,
4821                                         int (*okfn)(struct sk_buff *))
4822 {
4823         return selinux_ip_output(skb, PF_INET);
4824 }
4825
4826 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4827                                                 int ifindex,
4828                                                 u16 family)
4829 {
4830         struct sock *sk = skb->sk;
4831         struct sk_security_struct *sksec;
4832         struct common_audit_data ad;
4833         struct lsm_network_audit net = {0,};
4834         char *addrp;
4835         u8 proto;
4836
4837         if (sk == NULL)
4838                 return NF_ACCEPT;
4839         sksec = sk->sk_security;
4840
4841         ad.type = LSM_AUDIT_DATA_NET;
4842         ad.u.net = &net;
4843         ad.u.net->netif = ifindex;
4844         ad.u.net->family = family;
4845         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4846                 return NF_DROP;
4847
4848         if (selinux_secmark_enabled())
4849                 if (avc_has_perm(sksec->sid, skb->secmark,
4850                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4851                         return NF_DROP_ERR(-ECONNREFUSED);
4852
4853         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4854                 return NF_DROP_ERR(-ECONNREFUSED);
4855
4856         return NF_ACCEPT;
4857 }
4858
4859 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4860                                          u16 family)
4861 {
4862         u32 secmark_perm;
4863         u32 peer_sid;
4864         struct sock *sk;
4865         struct common_audit_data ad;
4866         struct lsm_network_audit net = {0,};
4867         char *addrp;
4868         u8 secmark_active;
4869         u8 peerlbl_active;
4870
4871         /* If any sort of compatibility mode is enabled then handoff processing
4872          * to the selinux_ip_postroute_compat() function to deal with the
4873          * special handling.  We do this in an attempt to keep this function
4874          * as fast and as clean as possible. */
4875         if (!selinux_policycap_netpeer)
4876                 return selinux_ip_postroute_compat(skb, ifindex, family);
4877
4878         secmark_active = selinux_secmark_enabled();
4879         peerlbl_active = selinux_peerlbl_enabled();
4880         if (!secmark_active && !peerlbl_active)
4881                 return NF_ACCEPT;
4882
4883         sk = skb->sk;
4884
4885 #ifdef CONFIG_XFRM
4886         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4887          * packet transformation so allow the packet to pass without any checks
4888          * since we'll have another chance to perform access control checks
4889          * when the packet is on it's final way out.
4890          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4891          *       is NULL, in this case go ahead and apply access control.
4892          * NOTE: if this is a local socket (skb->sk != NULL) that is in the
4893          *       TCP listening state we cannot wait until the XFRM processing
4894          *       is done as we will miss out on the SA label if we do;
4895          *       unfortunately, this means more work, but it is only once per
4896          *       connection. */
4897         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
4898             !(sk != NULL && sk->sk_state == TCP_LISTEN))
4899                 return NF_ACCEPT;
4900 #endif
4901
4902         if (sk == NULL) {
4903                 /* Without an associated socket the packet is either coming
4904                  * from the kernel or it is being forwarded; check the packet
4905                  * to determine which and if the packet is being forwarded
4906                  * query the packet directly to determine the security label. */
4907                 if (skb->skb_iif) {
4908                         secmark_perm = PACKET__FORWARD_OUT;
4909                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4910                                 return NF_DROP;
4911                 } else {
4912                         secmark_perm = PACKET__SEND;
4913                         peer_sid = SECINITSID_KERNEL;
4914                 }
4915         } else if (sk->sk_state == TCP_LISTEN) {
4916                 /* Locally generated packet but the associated socket is in the
4917                  * listening state which means this is a SYN-ACK packet.  In
4918                  * this particular case the correct security label is assigned
4919                  * to the connection/request_sock but unfortunately we can't
4920                  * query the request_sock as it isn't queued on the parent
4921                  * socket until after the SYN-ACK packet is sent; the only
4922                  * viable choice is to regenerate the label like we do in
4923                  * selinux_inet_conn_request().  See also selinux_ip_output()
4924                  * for similar problems. */
4925                 u32 skb_sid;
4926                 struct sk_security_struct *sksec = sk->sk_security;
4927                 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
4928                         return NF_DROP;
4929                 /* At this point, if the returned skb peerlbl is SECSID_NULL
4930                  * and the packet has been through at least one XFRM
4931                  * transformation then we must be dealing with the "final"
4932                  * form of labeled IPsec packet; since we've already applied
4933                  * all of our access controls on this packet we can safely
4934                  * pass the packet. */
4935                 if (skb_sid == SECSID_NULL) {
4936                         switch (family) {
4937                         case PF_INET:
4938                                 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
4939                                         return NF_ACCEPT;
4940                                 break;
4941                         case PF_INET6:
4942                                 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
4943                                         return NF_ACCEPT;
4944                         default:
4945                                 return NF_DROP_ERR(-ECONNREFUSED);
4946                         }
4947                 }
4948                 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
4949                         return NF_DROP;
4950                 secmark_perm = PACKET__SEND;
4951         } else {
4952                 /* Locally generated packet, fetch the security label from the
4953                  * associated socket. */
4954                 struct sk_security_struct *sksec = sk->sk_security;
4955                 peer_sid = sksec->sid;
4956                 secmark_perm = PACKET__SEND;
4957         }
4958
4959         ad.type = LSM_AUDIT_DATA_NET;
4960         ad.u.net = &net;
4961         ad.u.net->netif = ifindex;
4962         ad.u.net->family = family;
4963         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4964                 return NF_DROP;
4965
4966         if (secmark_active)
4967                 if (avc_has_perm(peer_sid, skb->secmark,
4968                                  SECCLASS_PACKET, secmark_perm, &ad))
4969                         return NF_DROP_ERR(-ECONNREFUSED);
4970
4971         if (peerlbl_active) {
4972                 u32 if_sid;
4973                 u32 node_sid;
4974
4975                 if (sel_netif_sid(ifindex, &if_sid))
4976                         return NF_DROP;
4977                 if (avc_has_perm(peer_sid, if_sid,
4978                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4979                         return NF_DROP_ERR(-ECONNREFUSED);
4980
4981                 if (sel_netnode_sid(addrp, family, &node_sid))
4982                         return NF_DROP;
4983                 if (avc_has_perm(peer_sid, node_sid,
4984                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4985                         return NF_DROP_ERR(-ECONNREFUSED);
4986         }
4987
4988         return NF_ACCEPT;
4989 }
4990
4991 static unsigned int selinux_ipv4_postroute(const struct nf_hook_ops *ops,
4992                                            struct sk_buff *skb,
4993                                            const struct net_device *in,
4994                                            const struct net_device *out,
4995                                            int (*okfn)(struct sk_buff *))
4996 {
4997         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4998 }
4999
5000 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5001 static unsigned int selinux_ipv6_postroute(const struct nf_hook_ops *ops,
5002                                            struct sk_buff *skb,
5003                                            const struct net_device *in,
5004                                            const struct net_device *out,
5005                                            int (*okfn)(struct sk_buff *))
5006 {
5007         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
5008 }
5009 #endif  /* IPV6 */
5010
5011 #endif  /* CONFIG_NETFILTER */
5012
5013 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5014 {
5015         int err;
5016
5017         err = cap_netlink_send(sk, skb);
5018         if (err)
5019                 return err;
5020
5021         return selinux_nlmsg_perm(sk, skb);
5022 }
5023
5024 static int ipc_alloc_security(struct task_struct *task,
5025                               struct kern_ipc_perm *perm,
5026                               u16 sclass)
5027 {
5028         struct ipc_security_struct *isec;
5029         u32 sid;
5030
5031         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
5032         if (!isec)
5033                 return -ENOMEM;
5034
5035         sid = task_sid(task);
5036         isec->sclass = sclass;
5037         isec->sid = sid;
5038         perm->security = isec;
5039
5040         return 0;
5041 }
5042
5043 static void ipc_free_security(struct kern_ipc_perm *perm)
5044 {
5045         struct ipc_security_struct *isec = perm->security;
5046         perm->security = NULL;
5047         kfree(isec);
5048 }
5049
5050 static int msg_msg_alloc_security(struct msg_msg *msg)
5051 {
5052         struct msg_security_struct *msec;
5053
5054         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
5055         if (!msec)
5056                 return -ENOMEM;
5057
5058         msec->sid = SECINITSID_UNLABELED;
5059         msg->security = msec;
5060
5061         return 0;
5062 }
5063
5064 static void msg_msg_free_security(struct msg_msg *msg)
5065 {
5066         struct msg_security_struct *msec = msg->security;
5067
5068         msg->security = NULL;
5069         kfree(msec);
5070 }
5071
5072 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5073                         u32 perms)
5074 {
5075         struct ipc_security_struct *isec;
5076         struct common_audit_data ad;
5077         u32 sid = current_sid();
5078
5079         isec = ipc_perms->security;
5080
5081         ad.type = LSM_AUDIT_DATA_IPC;
5082         ad.u.ipc_id = ipc_perms->key;
5083
5084         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
5085 }
5086
5087 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5088 {
5089         return msg_msg_alloc_security(msg);
5090 }
5091
5092 static void selinux_msg_msg_free_security(struct msg_msg *msg)
5093 {
5094         msg_msg_free_security(msg);
5095 }
5096
5097 /* message queue security operations */
5098 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
5099 {
5100         struct ipc_security_struct *isec;
5101         struct common_audit_data ad;
5102         u32 sid = current_sid();
5103         int rc;
5104
5105         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
5106         if (rc)
5107                 return rc;
5108
5109         isec = msq->q_perm.security;
5110
5111         ad.type = LSM_AUDIT_DATA_IPC;
5112         ad.u.ipc_id = msq->q_perm.key;
5113
5114         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5115                           MSGQ__CREATE, &ad);
5116         if (rc) {
5117                 ipc_free_security(&msq->q_perm);
5118                 return rc;
5119         }
5120         return 0;
5121 }
5122
5123 static void selinux_msg_queue_free_security(struct msg_queue *msq)
5124 {
5125         ipc_free_security(&msq->q_perm);
5126 }
5127
5128 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
5129 {
5130         struct ipc_security_struct *isec;
5131         struct common_audit_data ad;
5132         u32 sid = current_sid();
5133
5134         isec = msq->q_perm.security;
5135
5136         ad.type = LSM_AUDIT_DATA_IPC;
5137         ad.u.ipc_id = msq->q_perm.key;
5138
5139         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5140                             MSGQ__ASSOCIATE, &ad);
5141 }
5142
5143 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
5144 {
5145         int err;
5146         int perms;
5147
5148         switch (cmd) {
5149         case IPC_INFO:
5150         case MSG_INFO:
5151                 /* No specific object, just general system-wide information. */
5152                 return task_has_system(current, SYSTEM__IPC_INFO);
5153         case IPC_STAT:
5154         case MSG_STAT:
5155                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5156                 break;
5157         case IPC_SET:
5158                 perms = MSGQ__SETATTR;
5159                 break;
5160         case IPC_RMID:
5161                 perms = MSGQ__DESTROY;
5162                 break;
5163         default:
5164                 return 0;
5165         }
5166
5167         err = ipc_has_perm(&msq->q_perm, perms);
5168         return err;
5169 }
5170
5171 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
5172 {
5173         struct ipc_security_struct *isec;
5174         struct msg_security_struct *msec;
5175         struct common_audit_data ad;
5176         u32 sid = current_sid();
5177         int rc;
5178
5179         isec = msq->q_perm.security;
5180         msec = msg->security;
5181
5182         /*
5183          * First time through, need to assign label to the message
5184          */
5185         if (msec->sid == SECINITSID_UNLABELED) {
5186                 /*
5187                  * Compute new sid based on current process and
5188                  * message queue this message will be stored in
5189                  */
5190                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5191                                              NULL, &msec->sid);
5192                 if (rc)
5193                         return rc;
5194         }
5195
5196         ad.type = LSM_AUDIT_DATA_IPC;
5197         ad.u.ipc_id = msq->q_perm.key;
5198
5199         /* Can this process write to the queue? */
5200         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5201                           MSGQ__WRITE, &ad);
5202         if (!rc)
5203                 /* Can this process send the message */
5204                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5205                                   MSG__SEND, &ad);
5206         if (!rc)
5207                 /* Can the message be put in the queue? */
5208                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5209                                   MSGQ__ENQUEUE, &ad);
5210
5211         return rc;
5212 }
5213
5214 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5215                                     struct task_struct *target,
5216                                     long type, int mode)
5217 {
5218         struct ipc_security_struct *isec;
5219         struct msg_security_struct *msec;
5220         struct common_audit_data ad;
5221         u32 sid = task_sid(target);
5222         int rc;
5223
5224         isec = msq->q_perm.security;
5225         msec = msg->security;
5226
5227         ad.type = LSM_AUDIT_DATA_IPC;
5228         ad.u.ipc_id = msq->q_perm.key;
5229
5230         rc = avc_has_perm(sid, isec->sid,
5231                           SECCLASS_MSGQ, MSGQ__READ, &ad);
5232         if (!rc)
5233                 rc = avc_has_perm(sid, msec->sid,
5234                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
5235         return rc;
5236 }
5237
5238 /* Shared Memory security operations */
5239 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5240 {
5241         struct ipc_security_struct *isec;
5242         struct common_audit_data ad;
5243         u32 sid = current_sid();
5244         int rc;
5245
5246         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5247         if (rc)
5248                 return rc;
5249
5250         isec = shp->shm_perm.security;
5251
5252         ad.type = LSM_AUDIT_DATA_IPC;
5253         ad.u.ipc_id = shp->shm_perm.key;
5254
5255         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5256                           SHM__CREATE, &ad);
5257         if (rc) {
5258                 ipc_free_security(&shp->shm_perm);
5259                 return rc;
5260         }
5261         return 0;
5262 }
5263
5264 static void selinux_shm_free_security(struct shmid_kernel *shp)
5265 {
5266         ipc_free_security(&shp->shm_perm);
5267 }
5268
5269 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5270 {
5271         struct ipc_security_struct *isec;
5272         struct common_audit_data ad;
5273         u32 sid = current_sid();
5274
5275         isec = shp->shm_perm.security;
5276
5277         ad.type = LSM_AUDIT_DATA_IPC;
5278         ad.u.ipc_id = shp->shm_perm.key;
5279
5280         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5281                             SHM__ASSOCIATE, &ad);
5282 }
5283
5284 /* Note, at this point, shp is locked down */
5285 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5286 {
5287         int perms;
5288         int err;
5289
5290         switch (cmd) {
5291         case IPC_INFO:
5292         case SHM_INFO:
5293                 /* No specific object, just general system-wide information. */
5294                 return task_has_system(current, SYSTEM__IPC_INFO);
5295         case IPC_STAT:
5296         case SHM_STAT:
5297                 perms = SHM__GETATTR | SHM__ASSOCIATE;
5298                 break;
5299         case IPC_SET:
5300                 perms = SHM__SETATTR;
5301                 break;
5302         case SHM_LOCK:
5303         case SHM_UNLOCK:
5304                 perms = SHM__LOCK;
5305                 break;
5306         case IPC_RMID:
5307                 perms = SHM__DESTROY;
5308                 break;
5309         default:
5310                 return 0;
5311         }
5312
5313         err = ipc_has_perm(&shp->shm_perm, perms);
5314         return err;
5315 }
5316
5317 static int selinux_shm_shmat(struct shmid_kernel *shp,
5318                              char __user *shmaddr, int shmflg)
5319 {
5320         u32 perms;
5321
5322         if (shmflg & SHM_RDONLY)
5323                 perms = SHM__READ;
5324         else
5325                 perms = SHM__READ | SHM__WRITE;
5326
5327         return ipc_has_perm(&shp->shm_perm, perms);
5328 }
5329
5330 /* Semaphore security operations */
5331 static int selinux_sem_alloc_security(struct sem_array *sma)
5332 {
5333         struct ipc_security_struct *isec;
5334         struct common_audit_data ad;
5335         u32 sid = current_sid();
5336         int rc;
5337
5338         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5339         if (rc)
5340                 return rc;
5341
5342         isec = sma->sem_perm.security;
5343
5344         ad.type = LSM_AUDIT_DATA_IPC;
5345         ad.u.ipc_id = sma->sem_perm.key;
5346
5347         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5348                           SEM__CREATE, &ad);
5349         if (rc) {
5350                 ipc_free_security(&sma->sem_perm);
5351                 return rc;
5352         }
5353         return 0;
5354 }
5355
5356 static void selinux_sem_free_security(struct sem_array *sma)
5357 {
5358         ipc_free_security(&sma->sem_perm);
5359 }
5360
5361 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5362 {
5363         struct ipc_security_struct *isec;
5364         struct common_audit_data ad;
5365         u32 sid = current_sid();
5366
5367         isec = sma->sem_perm.security;
5368
5369         ad.type = LSM_AUDIT_DATA_IPC;
5370         ad.u.ipc_id = sma->sem_perm.key;
5371
5372         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5373                             SEM__ASSOCIATE, &ad);
5374 }
5375
5376 /* Note, at this point, sma is locked down */
5377 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5378 {
5379         int err;
5380         u32 perms;
5381
5382         switch (cmd) {
5383         case IPC_INFO:
5384         case SEM_INFO:
5385                 /* No specific object, just general system-wide information. */
5386                 return task_has_system(current, SYSTEM__IPC_INFO);
5387         case GETPID:
5388         case GETNCNT:
5389         case GETZCNT:
5390                 perms = SEM__GETATTR;
5391                 break;
5392         case GETVAL:
5393         case GETALL:
5394                 perms = SEM__READ;
5395                 break;
5396         case SETVAL:
5397         case SETALL:
5398                 perms = SEM__WRITE;
5399                 break;
5400         case IPC_RMID:
5401                 perms = SEM__DESTROY;
5402                 break;
5403         case IPC_SET:
5404                 perms = SEM__SETATTR;
5405                 break;
5406         case IPC_STAT:
5407         case SEM_STAT:
5408                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5409                 break;
5410         default:
5411                 return 0;
5412         }
5413
5414         err = ipc_has_perm(&sma->sem_perm, perms);
5415         return err;
5416 }
5417
5418 static int selinux_sem_semop(struct sem_array *sma,
5419                              struct sembuf *sops, unsigned nsops, int alter)
5420 {
5421         u32 perms;
5422
5423         if (alter)
5424                 perms = SEM__READ | SEM__WRITE;
5425         else
5426                 perms = SEM__READ;
5427
5428         return ipc_has_perm(&sma->sem_perm, perms);
5429 }
5430
5431 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5432 {
5433         u32 av = 0;
5434
5435         av = 0;
5436         if (flag & S_IRUGO)
5437                 av |= IPC__UNIX_READ;
5438         if (flag & S_IWUGO)
5439                 av |= IPC__UNIX_WRITE;
5440
5441         if (av == 0)
5442                 return 0;
5443
5444         return ipc_has_perm(ipcp, av);
5445 }
5446
5447 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5448 {
5449         struct ipc_security_struct *isec = ipcp->security;
5450         *secid = isec->sid;
5451 }
5452
5453 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5454 {
5455         if (inode)
5456                 inode_doinit_with_dentry(inode, dentry);
5457 }
5458
5459 static int selinux_getprocattr(struct task_struct *p,
5460                                char *name, char **value)
5461 {
5462         const struct task_security_struct *__tsec;
5463         u32 sid;
5464         int error;
5465         unsigned len;
5466
5467         if (current != p) {
5468                 error = current_has_perm(p, PROCESS__GETATTR);
5469                 if (error)
5470                         return error;
5471         }
5472
5473         rcu_read_lock();
5474         __tsec = __task_cred(p)->security;
5475
5476         if (!strcmp(name, "current"))
5477                 sid = __tsec->sid;
5478         else if (!strcmp(name, "prev"))
5479                 sid = __tsec->osid;
5480         else if (!strcmp(name, "exec"))
5481                 sid = __tsec->exec_sid;
5482         else if (!strcmp(name, "fscreate"))
5483                 sid = __tsec->create_sid;
5484         else if (!strcmp(name, "keycreate"))
5485                 sid = __tsec->keycreate_sid;
5486         else if (!strcmp(name, "sockcreate"))
5487                 sid = __tsec->sockcreate_sid;
5488         else
5489                 goto invalid;
5490         rcu_read_unlock();
5491
5492         if (!sid)
5493                 return 0;
5494
5495         error = security_sid_to_context(sid, value, &len);
5496         if (error)
5497                 return error;
5498         return len;
5499
5500 invalid:
5501         rcu_read_unlock();
5502         return -EINVAL;
5503 }
5504
5505 static int selinux_setprocattr(struct task_struct *p,
5506                                char *name, void *value, size_t size)
5507 {
5508         struct task_security_struct *tsec;
5509         struct task_struct *tracer;
5510         struct cred *new;
5511         u32 sid = 0, ptsid;
5512         int error;
5513         char *str = value;
5514
5515         if (current != p) {
5516                 /* SELinux only allows a process to change its own
5517                    security attributes. */
5518                 return -EACCES;
5519         }
5520
5521         /*
5522          * Basic control over ability to set these attributes at all.
5523          * current == p, but we'll pass them separately in case the
5524          * above restriction is ever removed.
5525          */
5526         if (!strcmp(name, "exec"))
5527                 error = current_has_perm(p, PROCESS__SETEXEC);
5528         else if (!strcmp(name, "fscreate"))
5529                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5530         else if (!strcmp(name, "keycreate"))
5531                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5532         else if (!strcmp(name, "sockcreate"))
5533                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5534         else if (!strcmp(name, "current"))
5535                 error = current_has_perm(p, PROCESS__SETCURRENT);
5536         else
5537                 error = -EINVAL;
5538         if (error)
5539                 return error;
5540
5541         /* Obtain a SID for the context, if one was specified. */
5542         if (size && str[1] && str[1] != '\n') {
5543                 if (str[size-1] == '\n') {
5544                         str[size-1] = 0;
5545                         size--;
5546                 }
5547                 error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5548                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5549                         if (!capable(CAP_MAC_ADMIN)) {
5550                                 struct audit_buffer *ab;
5551                                 size_t audit_size;
5552
5553                                 /* We strip a nul only if it is at the end, otherwise the
5554                                  * context contains a nul and we should audit that */
5555                                 if (str[size - 1] == '\0')
5556                                         audit_size = size - 1;
5557                                 else
5558                                         audit_size = size;
5559                                 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5560                                 audit_log_format(ab, "op=fscreate invalid_context=");
5561                                 audit_log_n_untrustedstring(ab, value, audit_size);
5562                                 audit_log_end(ab);
5563
5564                                 return error;
5565                         }
5566                         error = security_context_to_sid_force(value, size,
5567                                                               &sid);
5568                 }
5569                 if (error)
5570                         return error;
5571         }
5572
5573         new = prepare_creds();
5574         if (!new)
5575                 return -ENOMEM;
5576
5577         /* Permission checking based on the specified context is
5578            performed during the actual operation (execve,
5579            open/mkdir/...), when we know the full context of the
5580            operation.  See selinux_bprm_set_creds for the execve
5581            checks and may_create for the file creation checks. The
5582            operation will then fail if the context is not permitted. */
5583         tsec = new->security;
5584         if (!strcmp(name, "exec")) {
5585                 tsec->exec_sid = sid;
5586         } else if (!strcmp(name, "fscreate")) {
5587                 tsec->create_sid = sid;
5588         } else if (!strcmp(name, "keycreate")) {
5589                 error = may_create_key(sid, p);
5590                 if (error)
5591                         goto abort_change;
5592                 tsec->keycreate_sid = sid;
5593         } else if (!strcmp(name, "sockcreate")) {
5594                 tsec->sockcreate_sid = sid;
5595         } else if (!strcmp(name, "current")) {
5596                 error = -EINVAL;
5597                 if (sid == 0)
5598                         goto abort_change;
5599
5600                 /* Only allow single threaded processes to change context */
5601                 error = -EPERM;
5602                 if (!current_is_single_threaded()) {
5603                         error = security_bounded_transition(tsec->sid, sid);
5604                         if (error)
5605                                 goto abort_change;
5606                 }
5607
5608                 /* Check permissions for the transition. */
5609                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5610                                      PROCESS__DYNTRANSITION, NULL);
5611                 if (error)
5612                         goto abort_change;
5613
5614                 /* Check for ptracing, and update the task SID if ok.
5615                    Otherwise, leave SID unchanged and fail. */
5616                 ptsid = 0;
5617                 rcu_read_lock();
5618                 tracer = ptrace_parent(p);
5619                 if (tracer)
5620                         ptsid = task_sid(tracer);
5621                 rcu_read_unlock();
5622
5623                 if (tracer) {
5624                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5625                                              PROCESS__PTRACE, NULL);
5626                         if (error)
5627                                 goto abort_change;
5628                 }
5629
5630                 tsec->sid = sid;
5631         } else {
5632                 error = -EINVAL;
5633                 goto abort_change;
5634         }
5635
5636         commit_creds(new);
5637         return size;
5638
5639 abort_change:
5640         abort_creds(new);
5641         return error;
5642 }
5643
5644 static int selinux_ismaclabel(const char *name)
5645 {
5646         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
5647 }
5648
5649 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5650 {
5651         return security_sid_to_context(secid, secdata, seclen);
5652 }
5653
5654 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5655 {
5656         return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
5657 }
5658
5659 static void selinux_release_secctx(char *secdata, u32 seclen)
5660 {
5661         kfree(secdata);
5662 }
5663
5664 /*
5665  *      called with inode->i_mutex locked
5666  */
5667 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5668 {
5669         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5670 }
5671
5672 /*
5673  *      called with inode->i_mutex locked
5674  */
5675 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5676 {
5677         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5678 }
5679
5680 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5681 {
5682         int len = 0;
5683         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5684                                                 ctx, true);
5685         if (len < 0)
5686                 return len;
5687         *ctxlen = len;
5688         return 0;
5689 }
5690 #ifdef CONFIG_KEYS
5691
5692 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5693                              unsigned long flags)
5694 {
5695         const struct task_security_struct *tsec;
5696         struct key_security_struct *ksec;
5697
5698         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5699         if (!ksec)
5700                 return -ENOMEM;
5701
5702         tsec = cred->security;
5703         if (tsec->keycreate_sid)
5704                 ksec->sid = tsec->keycreate_sid;
5705         else
5706                 ksec->sid = tsec->sid;
5707
5708         k->security = ksec;
5709         return 0;
5710 }
5711
5712 static void selinux_key_free(struct key *k)
5713 {
5714         struct key_security_struct *ksec = k->security;
5715
5716         k->security = NULL;
5717         kfree(ksec);
5718 }
5719
5720 static int selinux_key_permission(key_ref_t key_ref,
5721                                   const struct cred *cred,
5722                                   key_perm_t perm)
5723 {
5724         struct key *key;
5725         struct key_security_struct *ksec;
5726         u32 sid;
5727
5728         /* if no specific permissions are requested, we skip the
5729            permission check. No serious, additional covert channels
5730            appear to be created. */
5731         if (perm == 0)
5732                 return 0;
5733
5734         sid = cred_sid(cred);
5735
5736         key = key_ref_to_ptr(key_ref);
5737         ksec = key->security;
5738
5739         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5740 }
5741
5742 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5743 {
5744         struct key_security_struct *ksec = key->security;
5745         char *context = NULL;
5746         unsigned len;
5747         int rc;
5748
5749         rc = security_sid_to_context(ksec->sid, &context, &len);
5750         if (!rc)
5751                 rc = len;
5752         *_buffer = context;
5753         return rc;
5754 }
5755
5756 #endif
5757
5758 static struct security_operations selinux_ops = {
5759         .name =                         "selinux",
5760
5761         .ptrace_access_check =          selinux_ptrace_access_check,
5762         .ptrace_traceme =               selinux_ptrace_traceme,
5763         .capget =                       selinux_capget,
5764         .capset =                       selinux_capset,
5765         .capable =                      selinux_capable,
5766         .quotactl =                     selinux_quotactl,
5767         .quota_on =                     selinux_quota_on,
5768         .syslog =                       selinux_syslog,
5769         .vm_enough_memory =             selinux_vm_enough_memory,
5770
5771         .netlink_send =                 selinux_netlink_send,
5772
5773         .bprm_set_creds =               selinux_bprm_set_creds,
5774         .bprm_committing_creds =        selinux_bprm_committing_creds,
5775         .bprm_committed_creds =         selinux_bprm_committed_creds,
5776         .bprm_secureexec =              selinux_bprm_secureexec,
5777
5778         .sb_alloc_security =            selinux_sb_alloc_security,
5779         .sb_free_security =             selinux_sb_free_security,
5780         .sb_copy_data =                 selinux_sb_copy_data,
5781         .sb_remount =                   selinux_sb_remount,
5782         .sb_kern_mount =                selinux_sb_kern_mount,
5783         .sb_show_options =              selinux_sb_show_options,
5784         .sb_statfs =                    selinux_sb_statfs,
5785         .sb_mount =                     selinux_mount,
5786         .sb_umount =                    selinux_umount,
5787         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5788         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5789         .sb_parse_opts_str =            selinux_parse_opts_str,
5790
5791         .dentry_init_security =         selinux_dentry_init_security,
5792
5793         .inode_alloc_security =         selinux_inode_alloc_security,
5794         .inode_free_security =          selinux_inode_free_security,
5795         .inode_init_security =          selinux_inode_init_security,
5796         .inode_create =                 selinux_inode_create,
5797         .inode_link =                   selinux_inode_link,
5798         .inode_unlink =                 selinux_inode_unlink,
5799         .inode_symlink =                selinux_inode_symlink,
5800         .inode_mkdir =                  selinux_inode_mkdir,
5801         .inode_rmdir =                  selinux_inode_rmdir,
5802         .inode_mknod =                  selinux_inode_mknod,
5803         .inode_rename =                 selinux_inode_rename,
5804         .inode_readlink =               selinux_inode_readlink,
5805         .inode_follow_link =            selinux_inode_follow_link,
5806         .inode_permission =             selinux_inode_permission,
5807         .inode_setattr =                selinux_inode_setattr,
5808         .inode_getattr =                selinux_inode_getattr,
5809         .inode_setxattr =               selinux_inode_setxattr,
5810         .inode_post_setxattr =          selinux_inode_post_setxattr,
5811         .inode_getxattr =               selinux_inode_getxattr,
5812         .inode_listxattr =              selinux_inode_listxattr,
5813         .inode_removexattr =            selinux_inode_removexattr,
5814         .inode_getsecurity =            selinux_inode_getsecurity,
5815         .inode_setsecurity =            selinux_inode_setsecurity,
5816         .inode_listsecurity =           selinux_inode_listsecurity,
5817         .inode_getsecid =               selinux_inode_getsecid,
5818
5819         .file_permission =              selinux_file_permission,
5820         .file_alloc_security =          selinux_file_alloc_security,
5821         .file_free_security =           selinux_file_free_security,
5822         .file_ioctl =                   selinux_file_ioctl,
5823         .mmap_file =                    selinux_mmap_file,
5824         .mmap_addr =                    selinux_mmap_addr,
5825         .file_mprotect =                selinux_file_mprotect,
5826         .file_lock =                    selinux_file_lock,
5827         .file_fcntl =                   selinux_file_fcntl,
5828         .file_set_fowner =              selinux_file_set_fowner,
5829         .file_send_sigiotask =          selinux_file_send_sigiotask,
5830         .file_receive =                 selinux_file_receive,
5831
5832         .file_open =                    selinux_file_open,
5833
5834         .task_create =                  selinux_task_create,
5835         .cred_alloc_blank =             selinux_cred_alloc_blank,
5836         .cred_free =                    selinux_cred_free,
5837         .cred_prepare =                 selinux_cred_prepare,
5838         .cred_transfer =                selinux_cred_transfer,
5839         .kernel_act_as =                selinux_kernel_act_as,
5840         .kernel_create_files_as =       selinux_kernel_create_files_as,
5841         .kernel_module_request =        selinux_kernel_module_request,
5842         .task_setpgid =                 selinux_task_setpgid,
5843         .task_getpgid =                 selinux_task_getpgid,
5844         .task_getsid =                  selinux_task_getsid,
5845         .task_getsecid =                selinux_task_getsecid,
5846         .task_setnice =                 selinux_task_setnice,
5847         .task_setioprio =               selinux_task_setioprio,
5848         .task_getioprio =               selinux_task_getioprio,
5849         .task_setrlimit =               selinux_task_setrlimit,
5850         .task_setscheduler =            selinux_task_setscheduler,
5851         .task_getscheduler =            selinux_task_getscheduler,
5852         .task_movememory =              selinux_task_movememory,
5853         .task_kill =                    selinux_task_kill,
5854         .task_wait =                    selinux_task_wait,
5855         .task_to_inode =                selinux_task_to_inode,
5856
5857         .ipc_permission =               selinux_ipc_permission,
5858         .ipc_getsecid =                 selinux_ipc_getsecid,
5859
5860         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5861         .msg_msg_free_security =        selinux_msg_msg_free_security,
5862
5863         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5864         .msg_queue_free_security =      selinux_msg_queue_free_security,
5865         .msg_queue_associate =          selinux_msg_queue_associate,
5866         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5867         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5868         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5869
5870         .shm_alloc_security =           selinux_shm_alloc_security,
5871         .shm_free_security =            selinux_shm_free_security,
5872         .shm_associate =                selinux_shm_associate,
5873         .shm_shmctl =                   selinux_shm_shmctl,
5874         .shm_shmat =                    selinux_shm_shmat,
5875
5876         .sem_alloc_security =           selinux_sem_alloc_security,
5877         .sem_free_security =            selinux_sem_free_security,
5878         .sem_associate =                selinux_sem_associate,
5879         .sem_semctl =                   selinux_sem_semctl,
5880         .sem_semop =                    selinux_sem_semop,
5881
5882         .d_instantiate =                selinux_d_instantiate,
5883
5884         .getprocattr =                  selinux_getprocattr,
5885         .setprocattr =                  selinux_setprocattr,
5886
5887         .ismaclabel =                   selinux_ismaclabel,
5888         .secid_to_secctx =              selinux_secid_to_secctx,
5889         .secctx_to_secid =              selinux_secctx_to_secid,
5890         .release_secctx =               selinux_release_secctx,
5891         .inode_notifysecctx =           selinux_inode_notifysecctx,
5892         .inode_setsecctx =              selinux_inode_setsecctx,
5893         .inode_getsecctx =              selinux_inode_getsecctx,
5894
5895         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5896         .unix_may_send =                selinux_socket_unix_may_send,
5897
5898         .socket_create =                selinux_socket_create,
5899         .socket_post_create =           selinux_socket_post_create,
5900         .socket_bind =                  selinux_socket_bind,
5901         .socket_connect =               selinux_socket_connect,
5902         .socket_listen =                selinux_socket_listen,
5903         .socket_accept =                selinux_socket_accept,
5904         .socket_sendmsg =               selinux_socket_sendmsg,
5905         .socket_recvmsg =               selinux_socket_recvmsg,
5906         .socket_getsockname =           selinux_socket_getsockname,
5907         .socket_getpeername =           selinux_socket_getpeername,
5908         .socket_getsockopt =            selinux_socket_getsockopt,
5909         .socket_setsockopt =            selinux_socket_setsockopt,
5910         .socket_shutdown =              selinux_socket_shutdown,
5911         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5912         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5913         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5914         .sk_alloc_security =            selinux_sk_alloc_security,
5915         .sk_free_security =             selinux_sk_free_security,
5916         .sk_clone_security =            selinux_sk_clone_security,
5917         .sk_getsecid =                  selinux_sk_getsecid,
5918         .sock_graft =                   selinux_sock_graft,
5919         .inet_conn_request =            selinux_inet_conn_request,
5920         .inet_csk_clone =               selinux_inet_csk_clone,
5921         .inet_conn_established =        selinux_inet_conn_established,
5922         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
5923         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
5924         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
5925         .req_classify_flow =            selinux_req_classify_flow,
5926         .tun_dev_alloc_security =       selinux_tun_dev_alloc_security,
5927         .tun_dev_free_security =        selinux_tun_dev_free_security,
5928         .tun_dev_create =               selinux_tun_dev_create,
5929         .tun_dev_attach_queue =         selinux_tun_dev_attach_queue,
5930         .tun_dev_attach =               selinux_tun_dev_attach,
5931         .tun_dev_open =                 selinux_tun_dev_open,
5932         .skb_owned_by =                 selinux_skb_owned_by,
5933
5934 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5935         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5936         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5937         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5938         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5939         .xfrm_state_alloc =             selinux_xfrm_state_alloc,
5940         .xfrm_state_alloc_acquire =     selinux_xfrm_state_alloc_acquire,
5941         .xfrm_state_free_security =     selinux_xfrm_state_free,
5942         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5943         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5944         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5945         .xfrm_decode_session =          selinux_xfrm_decode_session,
5946 #endif
5947
5948 #ifdef CONFIG_KEYS
5949         .key_alloc =                    selinux_key_alloc,
5950         .key_free =                     selinux_key_free,
5951         .key_permission =               selinux_key_permission,
5952         .key_getsecurity =              selinux_key_getsecurity,
5953 #endif
5954
5955 #ifdef CONFIG_AUDIT
5956         .audit_rule_init =              selinux_audit_rule_init,
5957         .audit_rule_known =             selinux_audit_rule_known,
5958         .audit_rule_match =             selinux_audit_rule_match,
5959         .audit_rule_free =              selinux_audit_rule_free,
5960 #endif
5961 };
5962
5963 static __init int selinux_init(void)
5964 {
5965         if (!security_module_enable(&selinux_ops)) {
5966                 selinux_enabled = 0;
5967                 return 0;
5968         }
5969
5970         if (!selinux_enabled) {
5971                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5972                 return 0;
5973         }
5974
5975         printk(KERN_INFO "SELinux:  Initializing.\n");
5976
5977         /* Set the security state for the initial task. */
5978         cred_init_security();
5979
5980         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5981
5982         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5983                                             sizeof(struct inode_security_struct),
5984                                             0, SLAB_PANIC, NULL);
5985         avc_init();
5986
5987         if (register_security(&selinux_ops))
5988                 panic("SELinux: Unable to register with kernel.\n");
5989
5990         if (selinux_enforcing)
5991                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5992         else
5993                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5994
5995         return 0;
5996 }
5997
5998 static void delayed_superblock_init(struct super_block *sb, void *unused)
5999 {
6000         superblock_doinit(sb, NULL);
6001 }
6002
6003 void selinux_complete_init(void)
6004 {
6005         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
6006
6007         /* Set up any superblocks initialized prior to the policy load. */
6008         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
6009         iterate_supers(delayed_superblock_init, NULL);
6010 }
6011
6012 /* SELinux requires early initialization in order to label
6013    all processes and objects when they are created. */
6014 security_initcall(selinux_init);
6015
6016 #if defined(CONFIG_NETFILTER)
6017
6018 static struct nf_hook_ops selinux_ipv4_ops[] = {
6019         {
6020                 .hook =         selinux_ipv4_postroute,
6021                 .owner =        THIS_MODULE,
6022                 .pf =           NFPROTO_IPV4,
6023                 .hooknum =      NF_INET_POST_ROUTING,
6024                 .priority =     NF_IP_PRI_SELINUX_LAST,
6025         },
6026         {
6027                 .hook =         selinux_ipv4_forward,
6028                 .owner =        THIS_MODULE,
6029                 .pf =           NFPROTO_IPV4,
6030                 .hooknum =      NF_INET_FORWARD,
6031                 .priority =     NF_IP_PRI_SELINUX_FIRST,
6032         },
6033         {
6034                 .hook =         selinux_ipv4_output,
6035                 .owner =        THIS_MODULE,
6036                 .pf =           NFPROTO_IPV4,
6037                 .hooknum =      NF_INET_LOCAL_OUT,
6038                 .priority =     NF_IP_PRI_SELINUX_FIRST,
6039         }
6040 };
6041
6042 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6043
6044 static struct nf_hook_ops selinux_ipv6_ops[] = {
6045         {
6046                 .hook =         selinux_ipv6_postroute,
6047                 .owner =        THIS_MODULE,
6048                 .pf =           NFPROTO_IPV6,
6049                 .hooknum =      NF_INET_POST_ROUTING,
6050                 .priority =     NF_IP6_PRI_SELINUX_LAST,
6051         },
6052         {
6053                 .hook =         selinux_ipv6_forward,
6054                 .owner =        THIS_MODULE,
6055                 .pf =           NFPROTO_IPV6,
6056                 .hooknum =      NF_INET_FORWARD,
6057                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
6058         }
6059 };
6060
6061 #endif  /* IPV6 */
6062
6063 static int __init selinux_nf_ip_init(void)
6064 {
6065         int err = 0;
6066
6067         if (!selinux_enabled)
6068                 goto out;
6069
6070         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
6071
6072         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
6073         if (err)
6074                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
6075
6076 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6077         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
6078         if (err)
6079                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
6080 #endif  /* IPV6 */
6081
6082 out:
6083         return err;
6084 }
6085
6086 __initcall(selinux_nf_ip_init);
6087
6088 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
6089 static void selinux_nf_ip_exit(void)
6090 {
6091         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
6092
6093         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
6094 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6095         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
6096 #endif  /* IPV6 */
6097 }
6098 #endif
6099
6100 #else /* CONFIG_NETFILTER */
6101
6102 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
6103 #define selinux_nf_ip_exit()
6104 #endif
6105
6106 #endif /* CONFIG_NETFILTER */
6107
6108 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
6109 static int selinux_disabled;
6110
6111 int selinux_disable(void)
6112 {
6113         if (ss_initialized) {
6114                 /* Not permitted after initial policy load. */
6115                 return -EINVAL;
6116         }
6117
6118         if (selinux_disabled) {
6119                 /* Only do this once. */
6120                 return -EINVAL;
6121         }
6122
6123         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
6124
6125         selinux_disabled = 1;
6126         selinux_enabled = 0;
6127
6128         reset_security_ops();
6129
6130         /* Try to destroy the avc node cache */
6131         avc_disable();
6132
6133         /* Unregister netfilter hooks. */
6134         selinux_nf_ip_exit();
6135
6136         /* Unregister selinuxfs. */
6137         exit_sel_fs();
6138
6139         return 0;
6140 }
6141 #endif