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         case F_OFD_GETLK:
3321         case F_OFD_SETLK:
3322         case F_OFD_SETLKW:
3323 #if BITS_PER_LONG == 32
3324         case F_GETLK64:
3325         case F_SETLK64:
3326         case F_SETLKW64:
3327 #endif
3328                 err = file_has_perm(cred, file, FILE__LOCK);
3329                 break;
3330         }
3331
3332         return err;
3333 }
3334
3335 static int selinux_file_set_fowner(struct file *file)
3336 {
3337         struct file_security_struct *fsec;
3338
3339         fsec = file->f_security;
3340         fsec->fown_sid = current_sid();
3341
3342         return 0;
3343 }
3344
3345 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3346                                        struct fown_struct *fown, int signum)
3347 {
3348         struct file *file;
3349         u32 sid = task_sid(tsk);
3350         u32 perm;
3351         struct file_security_struct *fsec;
3352
3353         /* struct fown_struct is never outside the context of a struct file */
3354         file = container_of(fown, struct file, f_owner);
3355
3356         fsec = file->f_security;
3357
3358         if (!signum)
3359                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3360         else
3361                 perm = signal_to_av(signum);
3362
3363         return avc_has_perm(fsec->fown_sid, sid,
3364                             SECCLASS_PROCESS, perm, NULL);
3365 }
3366
3367 static int selinux_file_receive(struct file *file)
3368 {
3369         const struct cred *cred = current_cred();
3370
3371         return file_has_perm(cred, file, file_to_av(file));
3372 }
3373
3374 static int selinux_file_open(struct file *file, const struct cred *cred)
3375 {
3376         struct file_security_struct *fsec;
3377         struct inode_security_struct *isec;
3378
3379         fsec = file->f_security;
3380         isec = file_inode(file)->i_security;
3381         /*
3382          * Save inode label and policy sequence number
3383          * at open-time so that selinux_file_permission
3384          * can determine whether revalidation is necessary.
3385          * Task label is already saved in the file security
3386          * struct as its SID.
3387          */
3388         fsec->isid = isec->sid;
3389         fsec->pseqno = avc_policy_seqno();
3390         /*
3391          * Since the inode label or policy seqno may have changed
3392          * between the selinux_inode_permission check and the saving
3393          * of state above, recheck that access is still permitted.
3394          * Otherwise, access might never be revalidated against the
3395          * new inode label or new policy.
3396          * This check is not redundant - do not remove.
3397          */
3398         return file_path_has_perm(cred, file, open_file_to_av(file));
3399 }
3400
3401 /* task security operations */
3402
3403 static int selinux_task_create(unsigned long clone_flags)
3404 {
3405         return current_has_perm(current, PROCESS__FORK);
3406 }
3407
3408 /*
3409  * allocate the SELinux part of blank credentials
3410  */
3411 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3412 {
3413         struct task_security_struct *tsec;
3414
3415         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3416         if (!tsec)
3417                 return -ENOMEM;
3418
3419         cred->security = tsec;
3420         return 0;
3421 }
3422
3423 /*
3424  * detach and free the LSM part of a set of credentials
3425  */
3426 static void selinux_cred_free(struct cred *cred)
3427 {
3428         struct task_security_struct *tsec = cred->security;
3429
3430         /*
3431          * cred->security == NULL if security_cred_alloc_blank() or
3432          * security_prepare_creds() returned an error.
3433          */
3434         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3435         cred->security = (void *) 0x7UL;
3436         kfree(tsec);
3437 }
3438
3439 /*
3440  * prepare a new set of credentials for modification
3441  */
3442 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3443                                 gfp_t gfp)
3444 {
3445         const struct task_security_struct *old_tsec;
3446         struct task_security_struct *tsec;
3447
3448         old_tsec = old->security;
3449
3450         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3451         if (!tsec)
3452                 return -ENOMEM;
3453
3454         new->security = tsec;
3455         return 0;
3456 }
3457
3458 /*
3459  * transfer the SELinux data to a blank set of creds
3460  */
3461 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3462 {
3463         const struct task_security_struct *old_tsec = old->security;
3464         struct task_security_struct *tsec = new->security;
3465
3466         *tsec = *old_tsec;
3467 }
3468
3469 /*
3470  * set the security data for a kernel service
3471  * - all the creation contexts are set to unlabelled
3472  */
3473 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3474 {
3475         struct task_security_struct *tsec = new->security;
3476         u32 sid = current_sid();
3477         int ret;
3478
3479         ret = avc_has_perm(sid, secid,
3480                            SECCLASS_KERNEL_SERVICE,
3481                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3482                            NULL);
3483         if (ret == 0) {
3484                 tsec->sid = secid;
3485                 tsec->create_sid = 0;
3486                 tsec->keycreate_sid = 0;
3487                 tsec->sockcreate_sid = 0;
3488         }
3489         return ret;
3490 }
3491
3492 /*
3493  * set the file creation context in a security record to the same as the
3494  * objective context of the specified inode
3495  */
3496 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3497 {
3498         struct inode_security_struct *isec = inode->i_security;
3499         struct task_security_struct *tsec = new->security;
3500         u32 sid = current_sid();
3501         int ret;
3502
3503         ret = avc_has_perm(sid, isec->sid,
3504                            SECCLASS_KERNEL_SERVICE,
3505                            KERNEL_SERVICE__CREATE_FILES_AS,
3506                            NULL);
3507
3508         if (ret == 0)
3509                 tsec->create_sid = isec->sid;
3510         return ret;
3511 }
3512
3513 static int selinux_kernel_module_request(char *kmod_name)
3514 {
3515         u32 sid;
3516         struct common_audit_data ad;
3517
3518         sid = task_sid(current);
3519
3520         ad.type = LSM_AUDIT_DATA_KMOD;
3521         ad.u.kmod_name = kmod_name;
3522
3523         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3524                             SYSTEM__MODULE_REQUEST, &ad);
3525 }
3526
3527 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3528 {
3529         return current_has_perm(p, PROCESS__SETPGID);
3530 }
3531
3532 static int selinux_task_getpgid(struct task_struct *p)
3533 {
3534         return current_has_perm(p, PROCESS__GETPGID);
3535 }
3536
3537 static int selinux_task_getsid(struct task_struct *p)
3538 {
3539         return current_has_perm(p, PROCESS__GETSESSION);
3540 }
3541
3542 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3543 {
3544         *secid = task_sid(p);
3545 }
3546
3547 static int selinux_task_setnice(struct task_struct *p, int nice)
3548 {
3549         int rc;
3550
3551         rc = cap_task_setnice(p, nice);
3552         if (rc)
3553                 return rc;
3554
3555         return current_has_perm(p, PROCESS__SETSCHED);
3556 }
3557
3558 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3559 {
3560         int rc;
3561
3562         rc = cap_task_setioprio(p, ioprio);
3563         if (rc)
3564                 return rc;
3565
3566         return current_has_perm(p, PROCESS__SETSCHED);
3567 }
3568
3569 static int selinux_task_getioprio(struct task_struct *p)
3570 {
3571         return current_has_perm(p, PROCESS__GETSCHED);
3572 }
3573
3574 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3575                 struct rlimit *new_rlim)
3576 {
3577         struct rlimit *old_rlim = p->signal->rlim + resource;
3578
3579         /* Control the ability to change the hard limit (whether
3580            lowering or raising it), so that the hard limit can
3581            later be used as a safe reset point for the soft limit
3582            upon context transitions.  See selinux_bprm_committing_creds. */
3583         if (old_rlim->rlim_max != new_rlim->rlim_max)
3584                 return current_has_perm(p, PROCESS__SETRLIMIT);
3585
3586         return 0;
3587 }
3588
3589 static int selinux_task_setscheduler(struct task_struct *p)
3590 {
3591         int rc;
3592
3593         rc = cap_task_setscheduler(p);
3594         if (rc)
3595                 return rc;
3596
3597         return current_has_perm(p, PROCESS__SETSCHED);
3598 }
3599
3600 static int selinux_task_getscheduler(struct task_struct *p)
3601 {
3602         return current_has_perm(p, PROCESS__GETSCHED);
3603 }
3604
3605 static int selinux_task_movememory(struct task_struct *p)
3606 {
3607         return current_has_perm(p, PROCESS__SETSCHED);
3608 }
3609
3610 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3611                                 int sig, u32 secid)
3612 {
3613         u32 perm;
3614         int rc;
3615
3616         if (!sig)
3617                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3618         else
3619                 perm = signal_to_av(sig);
3620         if (secid)
3621                 rc = avc_has_perm(secid, task_sid(p),
3622                                   SECCLASS_PROCESS, perm, NULL);
3623         else
3624                 rc = current_has_perm(p, perm);
3625         return rc;
3626 }
3627
3628 static int selinux_task_wait(struct task_struct *p)
3629 {
3630         return task_has_perm(p, current, PROCESS__SIGCHLD);
3631 }
3632
3633 static void selinux_task_to_inode(struct task_struct *p,
3634                                   struct inode *inode)
3635 {
3636         struct inode_security_struct *isec = inode->i_security;
3637         u32 sid = task_sid(p);
3638
3639         isec->sid = sid;
3640         isec->initialized = 1;
3641 }
3642
3643 /* Returns error only if unable to parse addresses */
3644 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3645                         struct common_audit_data *ad, u8 *proto)
3646 {
3647         int offset, ihlen, ret = -EINVAL;
3648         struct iphdr _iph, *ih;
3649
3650         offset = skb_network_offset(skb);
3651         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3652         if (ih == NULL)
3653                 goto out;
3654
3655         ihlen = ih->ihl * 4;
3656         if (ihlen < sizeof(_iph))
3657                 goto out;
3658
3659         ad->u.net->v4info.saddr = ih->saddr;
3660         ad->u.net->v4info.daddr = ih->daddr;
3661         ret = 0;
3662
3663         if (proto)
3664                 *proto = ih->protocol;
3665
3666         switch (ih->protocol) {
3667         case IPPROTO_TCP: {
3668                 struct tcphdr _tcph, *th;
3669
3670                 if (ntohs(ih->frag_off) & IP_OFFSET)
3671                         break;
3672
3673                 offset += ihlen;
3674                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3675                 if (th == NULL)
3676                         break;
3677
3678                 ad->u.net->sport = th->source;
3679                 ad->u.net->dport = th->dest;
3680                 break;
3681         }
3682
3683         case IPPROTO_UDP: {
3684                 struct udphdr _udph, *uh;
3685
3686                 if (ntohs(ih->frag_off) & IP_OFFSET)
3687                         break;
3688
3689                 offset += ihlen;
3690                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3691                 if (uh == NULL)
3692                         break;
3693
3694                 ad->u.net->sport = uh->source;
3695                 ad->u.net->dport = uh->dest;
3696                 break;
3697         }
3698
3699         case IPPROTO_DCCP: {
3700                 struct dccp_hdr _dccph, *dh;
3701
3702                 if (ntohs(ih->frag_off) & IP_OFFSET)
3703                         break;
3704
3705                 offset += ihlen;
3706                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3707                 if (dh == NULL)
3708                         break;
3709
3710                 ad->u.net->sport = dh->dccph_sport;
3711                 ad->u.net->dport = dh->dccph_dport;
3712                 break;
3713         }
3714
3715         default:
3716                 break;
3717         }
3718 out:
3719         return ret;
3720 }
3721
3722 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3723
3724 /* Returns error only if unable to parse addresses */
3725 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3726                         struct common_audit_data *ad, u8 *proto)
3727 {
3728         u8 nexthdr;
3729         int ret = -EINVAL, offset;
3730         struct ipv6hdr _ipv6h, *ip6;
3731         __be16 frag_off;
3732
3733         offset = skb_network_offset(skb);
3734         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3735         if (ip6 == NULL)
3736                 goto out;
3737
3738         ad->u.net->v6info.saddr = ip6->saddr;
3739         ad->u.net->v6info.daddr = ip6->daddr;
3740         ret = 0;
3741
3742         nexthdr = ip6->nexthdr;
3743         offset += sizeof(_ipv6h);
3744         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3745         if (offset < 0)
3746                 goto out;
3747
3748         if (proto)
3749                 *proto = nexthdr;
3750
3751         switch (nexthdr) {
3752         case IPPROTO_TCP: {
3753                 struct tcphdr _tcph, *th;
3754
3755                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3756                 if (th == NULL)
3757                         break;
3758
3759                 ad->u.net->sport = th->source;
3760                 ad->u.net->dport = th->dest;
3761                 break;
3762         }
3763
3764         case IPPROTO_UDP: {
3765                 struct udphdr _udph, *uh;
3766
3767                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3768                 if (uh == NULL)
3769                         break;
3770
3771                 ad->u.net->sport = uh->source;
3772                 ad->u.net->dport = uh->dest;
3773                 break;
3774         }
3775
3776         case IPPROTO_DCCP: {
3777                 struct dccp_hdr _dccph, *dh;
3778
3779                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3780                 if (dh == NULL)
3781                         break;
3782
3783                 ad->u.net->sport = dh->dccph_sport;
3784                 ad->u.net->dport = dh->dccph_dport;
3785                 break;
3786         }
3787
3788         /* includes fragments */
3789         default:
3790                 break;
3791         }
3792 out:
3793         return ret;
3794 }
3795
3796 #endif /* IPV6 */
3797
3798 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3799                              char **_addrp, int src, u8 *proto)
3800 {
3801         char *addrp;
3802         int ret;
3803
3804         switch (ad->u.net->family) {
3805         case PF_INET:
3806                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3807                 if (ret)
3808                         goto parse_error;
3809                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
3810                                        &ad->u.net->v4info.daddr);
3811                 goto okay;
3812
3813 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3814         case PF_INET6:
3815                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3816                 if (ret)
3817                         goto parse_error;
3818                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
3819                                        &ad->u.net->v6info.daddr);
3820                 goto okay;
3821 #endif  /* IPV6 */
3822         default:
3823                 addrp = NULL;
3824                 goto okay;
3825         }
3826
3827 parse_error:
3828         printk(KERN_WARNING
3829                "SELinux: failure in selinux_parse_skb(),"
3830                " unable to parse packet\n");
3831         return ret;
3832
3833 okay:
3834         if (_addrp)
3835                 *_addrp = addrp;
3836         return 0;
3837 }
3838
3839 /**
3840  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3841  * @skb: the packet
3842  * @family: protocol family
3843  * @sid: the packet's peer label SID
3844  *
3845  * Description:
3846  * Check the various different forms of network peer labeling and determine
3847  * the peer label/SID for the packet; most of the magic actually occurs in
3848  * the security server function security_net_peersid_cmp().  The function
3849  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3850  * or -EACCES if @sid is invalid due to inconsistencies with the different
3851  * peer labels.
3852  *
3853  */
3854 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3855 {
3856         int err;
3857         u32 xfrm_sid;
3858         u32 nlbl_sid;
3859         u32 nlbl_type;
3860
3861         err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
3862         if (unlikely(err))
3863                 return -EACCES;
3864         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3865         if (unlikely(err))
3866                 return -EACCES;
3867
3868         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3869         if (unlikely(err)) {
3870                 printk(KERN_WARNING
3871                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3872                        " unable to determine packet's peer label\n");
3873                 return -EACCES;
3874         }
3875
3876         return 0;
3877 }
3878
3879 /**
3880  * selinux_conn_sid - Determine the child socket label for a connection
3881  * @sk_sid: the parent socket's SID
3882  * @skb_sid: the packet's SID
3883  * @conn_sid: the resulting connection SID
3884  *
3885  * If @skb_sid is valid then the user:role:type information from @sk_sid is
3886  * combined with the MLS information from @skb_sid in order to create
3887  * @conn_sid.  If @skb_sid is not valid then then @conn_sid is simply a copy
3888  * of @sk_sid.  Returns zero on success, negative values on failure.
3889  *
3890  */
3891 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
3892 {
3893         int err = 0;
3894
3895         if (skb_sid != SECSID_NULL)
3896                 err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid);
3897         else
3898                 *conn_sid = sk_sid;
3899
3900         return err;
3901 }
3902
3903 /* socket security operations */
3904
3905 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3906                                  u16 secclass, u32 *socksid)
3907 {
3908         if (tsec->sockcreate_sid > SECSID_NULL) {
3909                 *socksid = tsec->sockcreate_sid;
3910                 return 0;
3911         }
3912
3913         return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3914                                        socksid);
3915 }
3916
3917 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3918 {
3919         struct sk_security_struct *sksec = sk->sk_security;
3920         struct common_audit_data ad;
3921         struct lsm_network_audit net = {0,};
3922         u32 tsid = task_sid(task);
3923
3924         if (sksec->sid == SECINITSID_KERNEL)
3925                 return 0;
3926
3927         ad.type = LSM_AUDIT_DATA_NET;
3928         ad.u.net = &net;
3929         ad.u.net->sk = sk;
3930
3931         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3932 }
3933
3934 static int selinux_socket_create(int family, int type,
3935                                  int protocol, int kern)
3936 {
3937         const struct task_security_struct *tsec = current_security();
3938         u32 newsid;
3939         u16 secclass;
3940         int rc;
3941
3942         if (kern)
3943                 return 0;
3944
3945         secclass = socket_type_to_security_class(family, type, protocol);
3946         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3947         if (rc)
3948                 return rc;
3949
3950         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3951 }
3952
3953 static int selinux_socket_post_create(struct socket *sock, int family,
3954                                       int type, int protocol, int kern)
3955 {
3956         const struct task_security_struct *tsec = current_security();
3957         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3958         struct sk_security_struct *sksec;
3959         int err = 0;
3960
3961         isec->sclass = socket_type_to_security_class(family, type, protocol);
3962
3963         if (kern)
3964                 isec->sid = SECINITSID_KERNEL;
3965         else {
3966                 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3967                 if (err)
3968                         return err;
3969         }
3970
3971         isec->initialized = 1;
3972
3973         if (sock->sk) {
3974                 sksec = sock->sk->sk_security;
3975                 sksec->sid = isec->sid;
3976                 sksec->sclass = isec->sclass;
3977                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3978         }
3979
3980         return err;
3981 }
3982
3983 /* Range of port numbers used to automatically bind.
3984    Need to determine whether we should perform a name_bind
3985    permission check between the socket and the port number. */
3986
3987 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3988 {
3989         struct sock *sk = sock->sk;
3990         u16 family;
3991         int err;
3992
3993         err = sock_has_perm(current, sk, SOCKET__BIND);
3994         if (err)
3995                 goto out;
3996
3997         /*
3998          * If PF_INET or PF_INET6, check name_bind permission for the port.
3999          * Multiple address binding for SCTP is not supported yet: we just
4000          * check the first address now.
4001          */
4002         family = sk->sk_family;
4003         if (family == PF_INET || family == PF_INET6) {
4004                 char *addrp;
4005                 struct sk_security_struct *sksec = sk->sk_security;
4006                 struct common_audit_data ad;
4007                 struct lsm_network_audit net = {0,};
4008                 struct sockaddr_in *addr4 = NULL;
4009                 struct sockaddr_in6 *addr6 = NULL;
4010                 unsigned short snum;
4011                 u32 sid, node_perm;
4012
4013                 if (family == PF_INET) {
4014                         addr4 = (struct sockaddr_in *)address;
4015                         snum = ntohs(addr4->sin_port);
4016                         addrp = (char *)&addr4->sin_addr.s_addr;
4017                 } else {
4018                         addr6 = (struct sockaddr_in6 *)address;
4019                         snum = ntohs(addr6->sin6_port);
4020                         addrp = (char *)&addr6->sin6_addr.s6_addr;
4021                 }
4022
4023                 if (snum) {
4024                         int low, high;
4025
4026                         inet_get_local_port_range(sock_net(sk), &low, &high);
4027
4028                         if (snum < max(PROT_SOCK, low) || snum > high) {
4029                                 err = sel_netport_sid(sk->sk_protocol,
4030                                                       snum, &sid);
4031                                 if (err)
4032                                         goto out;
4033                                 ad.type = LSM_AUDIT_DATA_NET;
4034                                 ad.u.net = &net;
4035                                 ad.u.net->sport = htons(snum);
4036                                 ad.u.net->family = family;
4037                                 err = avc_has_perm(sksec->sid, sid,
4038                                                    sksec->sclass,
4039                                                    SOCKET__NAME_BIND, &ad);
4040                                 if (err)
4041                                         goto out;
4042                         }
4043                 }
4044
4045                 switch (sksec->sclass) {
4046                 case SECCLASS_TCP_SOCKET:
4047                         node_perm = TCP_SOCKET__NODE_BIND;
4048                         break;
4049
4050                 case SECCLASS_UDP_SOCKET:
4051                         node_perm = UDP_SOCKET__NODE_BIND;
4052                         break;
4053
4054                 case SECCLASS_DCCP_SOCKET:
4055                         node_perm = DCCP_SOCKET__NODE_BIND;
4056                         break;
4057
4058                 default:
4059                         node_perm = RAWIP_SOCKET__NODE_BIND;
4060                         break;
4061                 }
4062
4063                 err = sel_netnode_sid(addrp, family, &sid);
4064                 if (err)
4065                         goto out;
4066
4067                 ad.type = LSM_AUDIT_DATA_NET;
4068                 ad.u.net = &net;
4069                 ad.u.net->sport = htons(snum);
4070                 ad.u.net->family = family;
4071
4072                 if (family == PF_INET)
4073                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4074                 else
4075                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4076
4077                 err = avc_has_perm(sksec->sid, sid,
4078                                    sksec->sclass, node_perm, &ad);
4079                 if (err)
4080                         goto out;
4081         }
4082 out:
4083         return err;
4084 }
4085
4086 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
4087 {
4088         struct sock *sk = sock->sk;
4089         struct sk_security_struct *sksec = sk->sk_security;
4090         int err;
4091
4092         err = sock_has_perm(current, sk, SOCKET__CONNECT);
4093         if (err)
4094                 return err;
4095
4096         /*
4097          * If a TCP or DCCP socket, check name_connect permission for the port.
4098          */
4099         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4100             sksec->sclass == SECCLASS_DCCP_SOCKET) {
4101                 struct common_audit_data ad;
4102                 struct lsm_network_audit net = {0,};
4103                 struct sockaddr_in *addr4 = NULL;
4104                 struct sockaddr_in6 *addr6 = NULL;
4105                 unsigned short snum;
4106                 u32 sid, perm;
4107
4108                 if (sk->sk_family == PF_INET) {
4109                         addr4 = (struct sockaddr_in *)address;
4110                         if (addrlen < sizeof(struct sockaddr_in))
4111                                 return -EINVAL;
4112                         snum = ntohs(addr4->sin_port);
4113                 } else {
4114                         addr6 = (struct sockaddr_in6 *)address;
4115                         if (addrlen < SIN6_LEN_RFC2133)
4116                                 return -EINVAL;
4117                         snum = ntohs(addr6->sin6_port);
4118                 }
4119
4120                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4121                 if (err)
4122                         goto out;
4123
4124                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
4125                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
4126
4127                 ad.type = LSM_AUDIT_DATA_NET;
4128                 ad.u.net = &net;
4129                 ad.u.net->dport = htons(snum);
4130                 ad.u.net->family = sk->sk_family;
4131                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4132                 if (err)
4133                         goto out;
4134         }
4135
4136         err = selinux_netlbl_socket_connect(sk, address);
4137
4138 out:
4139         return err;
4140 }
4141
4142 static int selinux_socket_listen(struct socket *sock, int backlog)
4143 {
4144         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
4145 }
4146
4147 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4148 {
4149         int err;
4150         struct inode_security_struct *isec;
4151         struct inode_security_struct *newisec;
4152
4153         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4154         if (err)
4155                 return err;
4156
4157         newisec = SOCK_INODE(newsock)->i_security;
4158
4159         isec = SOCK_INODE(sock)->i_security;
4160         newisec->sclass = isec->sclass;
4161         newisec->sid = isec->sid;
4162         newisec->initialized = 1;
4163
4164         return 0;
4165 }
4166
4167 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4168                                   int size)
4169 {
4170         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4171 }
4172
4173 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4174                                   int size, int flags)
4175 {
4176         return sock_has_perm(current, sock->sk, SOCKET__READ);
4177 }
4178
4179 static int selinux_socket_getsockname(struct socket *sock)
4180 {
4181         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4182 }
4183
4184 static int selinux_socket_getpeername(struct socket *sock)
4185 {
4186         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4187 }
4188
4189 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4190 {
4191         int err;
4192
4193         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4194         if (err)
4195                 return err;
4196
4197         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4198 }
4199
4200 static int selinux_socket_getsockopt(struct socket *sock, int level,
4201                                      int optname)
4202 {
4203         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4204 }
4205
4206 static int selinux_socket_shutdown(struct socket *sock, int how)
4207 {
4208         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4209 }
4210
4211 static int selinux_socket_unix_stream_connect(struct sock *sock,
4212                                               struct sock *other,
4213                                               struct sock *newsk)
4214 {
4215         struct sk_security_struct *sksec_sock = sock->sk_security;
4216         struct sk_security_struct *sksec_other = other->sk_security;
4217         struct sk_security_struct *sksec_new = newsk->sk_security;
4218         struct common_audit_data ad;
4219         struct lsm_network_audit net = {0,};
4220         int err;
4221
4222         ad.type = LSM_AUDIT_DATA_NET;
4223         ad.u.net = &net;
4224         ad.u.net->sk = other;
4225
4226         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4227                            sksec_other->sclass,
4228                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4229         if (err)
4230                 return err;
4231
4232         /* server child socket */
4233         sksec_new->peer_sid = sksec_sock->sid;
4234         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4235                                     &sksec_new->sid);
4236         if (err)
4237                 return err;
4238
4239         /* connecting socket */
4240         sksec_sock->peer_sid = sksec_new->sid;
4241
4242         return 0;
4243 }
4244
4245 static int selinux_socket_unix_may_send(struct socket *sock,
4246                                         struct socket *other)
4247 {
4248         struct sk_security_struct *ssec = sock->sk->sk_security;
4249         struct sk_security_struct *osec = other->sk->sk_security;
4250         struct common_audit_data ad;
4251         struct lsm_network_audit net = {0,};
4252
4253         ad.type = LSM_AUDIT_DATA_NET;
4254         ad.u.net = &net;
4255         ad.u.net->sk = other->sk;
4256
4257         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4258                             &ad);
4259 }
4260
4261 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4262                                     u32 peer_sid,
4263                                     struct common_audit_data *ad)
4264 {
4265         int err;
4266         u32 if_sid;
4267         u32 node_sid;
4268
4269         err = sel_netif_sid(ifindex, &if_sid);
4270         if (err)
4271                 return err;
4272         err = avc_has_perm(peer_sid, if_sid,
4273                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4274         if (err)
4275                 return err;
4276
4277         err = sel_netnode_sid(addrp, family, &node_sid);
4278         if (err)
4279                 return err;
4280         return avc_has_perm(peer_sid, node_sid,
4281                             SECCLASS_NODE, NODE__RECVFROM, ad);
4282 }
4283
4284 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4285                                        u16 family)
4286 {
4287         int err = 0;
4288         struct sk_security_struct *sksec = sk->sk_security;
4289         u32 sk_sid = sksec->sid;
4290         struct common_audit_data ad;
4291         struct lsm_network_audit net = {0,};
4292         char *addrp;
4293
4294         ad.type = LSM_AUDIT_DATA_NET;
4295         ad.u.net = &net;
4296         ad.u.net->netif = skb->skb_iif;
4297         ad.u.net->family = family;
4298         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4299         if (err)
4300                 return err;
4301
4302         if (selinux_secmark_enabled()) {
4303                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4304                                    PACKET__RECV, &ad);
4305                 if (err)
4306                         return err;
4307         }
4308
4309         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4310         if (err)
4311                 return err;
4312         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4313
4314         return err;
4315 }
4316
4317 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4318 {
4319         int err;
4320         struct sk_security_struct *sksec = sk->sk_security;
4321         u16 family = sk->sk_family;
4322         u32 sk_sid = sksec->sid;
4323         struct common_audit_data ad;
4324         struct lsm_network_audit net = {0,};
4325         char *addrp;
4326         u8 secmark_active;
4327         u8 peerlbl_active;
4328
4329         if (family != PF_INET && family != PF_INET6)
4330                 return 0;
4331
4332         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4333         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4334                 family = PF_INET;
4335
4336         /* If any sort of compatibility mode is enabled then handoff processing
4337          * to the selinux_sock_rcv_skb_compat() function to deal with the
4338          * special handling.  We do this in an attempt to keep this function
4339          * as fast and as clean as possible. */
4340         if (!selinux_policycap_netpeer)
4341                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4342
4343         secmark_active = selinux_secmark_enabled();
4344         peerlbl_active = selinux_peerlbl_enabled();
4345         if (!secmark_active && !peerlbl_active)
4346                 return 0;
4347
4348         ad.type = LSM_AUDIT_DATA_NET;
4349         ad.u.net = &net;
4350         ad.u.net->netif = skb->skb_iif;
4351         ad.u.net->family = family;
4352         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4353         if (err)
4354                 return err;
4355
4356         if (peerlbl_active) {
4357                 u32 peer_sid;
4358
4359                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4360                 if (err)
4361                         return err;
4362                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4363                                                peer_sid, &ad);
4364                 if (err) {
4365                         selinux_netlbl_err(skb, err, 0);
4366                         return err;
4367                 }
4368                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4369                                    PEER__RECV, &ad);
4370                 if (err) {
4371                         selinux_netlbl_err(skb, err, 0);
4372                         return err;
4373                 }
4374         }
4375
4376         if (secmark_active) {
4377                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4378                                    PACKET__RECV, &ad);
4379                 if (err)
4380                         return err;
4381         }
4382
4383         return err;
4384 }
4385
4386 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4387                                             int __user *optlen, unsigned len)
4388 {
4389         int err = 0;
4390         char *scontext;
4391         u32 scontext_len;
4392         struct sk_security_struct *sksec = sock->sk->sk_security;
4393         u32 peer_sid = SECSID_NULL;
4394
4395         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4396             sksec->sclass == SECCLASS_TCP_SOCKET)
4397                 peer_sid = sksec->peer_sid;
4398         if (peer_sid == SECSID_NULL)
4399                 return -ENOPROTOOPT;
4400
4401         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4402         if (err)
4403                 return err;
4404
4405         if (scontext_len > len) {
4406                 err = -ERANGE;
4407                 goto out_len;
4408         }
4409
4410         if (copy_to_user(optval, scontext, scontext_len))
4411                 err = -EFAULT;
4412
4413 out_len:
4414         if (put_user(scontext_len, optlen))
4415                 err = -EFAULT;
4416         kfree(scontext);
4417         return err;
4418 }
4419
4420 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4421 {
4422         u32 peer_secid = SECSID_NULL;
4423         u16 family;
4424
4425         if (skb && skb->protocol == htons(ETH_P_IP))
4426                 family = PF_INET;
4427         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4428                 family = PF_INET6;
4429         else if (sock)
4430                 family = sock->sk->sk_family;
4431         else
4432                 goto out;
4433
4434         if (sock && family == PF_UNIX)
4435                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4436         else if (skb)
4437                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4438
4439 out:
4440         *secid = peer_secid;
4441         if (peer_secid == SECSID_NULL)
4442                 return -EINVAL;
4443         return 0;
4444 }
4445
4446 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4447 {
4448         struct sk_security_struct *sksec;
4449
4450         sksec = kzalloc(sizeof(*sksec), priority);
4451         if (!sksec)
4452                 return -ENOMEM;
4453
4454         sksec->peer_sid = SECINITSID_UNLABELED;
4455         sksec->sid = SECINITSID_UNLABELED;
4456         selinux_netlbl_sk_security_reset(sksec);
4457         sk->sk_security = sksec;
4458
4459         return 0;
4460 }
4461
4462 static void selinux_sk_free_security(struct sock *sk)
4463 {
4464         struct sk_security_struct *sksec = sk->sk_security;
4465
4466         sk->sk_security = NULL;
4467         selinux_netlbl_sk_security_free(sksec);
4468         kfree(sksec);
4469 }
4470
4471 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4472 {
4473         struct sk_security_struct *sksec = sk->sk_security;
4474         struct sk_security_struct *newsksec = newsk->sk_security;
4475
4476         newsksec->sid = sksec->sid;
4477         newsksec->peer_sid = sksec->peer_sid;
4478         newsksec->sclass = sksec->sclass;
4479
4480         selinux_netlbl_sk_security_reset(newsksec);
4481 }
4482
4483 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4484 {
4485         if (!sk)
4486                 *secid = SECINITSID_ANY_SOCKET;
4487         else {
4488                 struct sk_security_struct *sksec = sk->sk_security;
4489
4490                 *secid = sksec->sid;
4491         }
4492 }
4493
4494 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4495 {
4496         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4497         struct sk_security_struct *sksec = sk->sk_security;
4498
4499         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4500             sk->sk_family == PF_UNIX)
4501                 isec->sid = sksec->sid;
4502         sksec->sclass = isec->sclass;
4503 }
4504
4505 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4506                                      struct request_sock *req)
4507 {
4508         struct sk_security_struct *sksec = sk->sk_security;
4509         int err;
4510         u16 family = req->rsk_ops->family;
4511         u32 connsid;
4512         u32 peersid;
4513
4514         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4515         if (err)
4516                 return err;
4517         err = selinux_conn_sid(sksec->sid, peersid, &connsid);
4518         if (err)
4519                 return err;
4520         req->secid = connsid;
4521         req->peer_secid = peersid;
4522
4523         return selinux_netlbl_inet_conn_request(req, family);
4524 }
4525
4526 static void selinux_inet_csk_clone(struct sock *newsk,
4527                                    const struct request_sock *req)
4528 {
4529         struct sk_security_struct *newsksec = newsk->sk_security;
4530
4531         newsksec->sid = req->secid;
4532         newsksec->peer_sid = req->peer_secid;
4533         /* NOTE: Ideally, we should also get the isec->sid for the
4534            new socket in sync, but we don't have the isec available yet.
4535            So we will wait until sock_graft to do it, by which
4536            time it will have been created and available. */
4537
4538         /* We don't need to take any sort of lock here as we are the only
4539          * thread with access to newsksec */
4540         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4541 }
4542
4543 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4544 {
4545         u16 family = sk->sk_family;
4546         struct sk_security_struct *sksec = sk->sk_security;
4547
4548         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4549         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4550                 family = PF_INET;
4551
4552         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4553 }
4554
4555 static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
4556 {
4557         skb_set_owner_w(skb, sk);
4558 }
4559
4560 static int selinux_secmark_relabel_packet(u32 sid)
4561 {
4562         const struct task_security_struct *__tsec;
4563         u32 tsid;
4564
4565         __tsec = current_security();
4566         tsid = __tsec->sid;
4567
4568         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4569 }
4570
4571 static void selinux_secmark_refcount_inc(void)
4572 {
4573         atomic_inc(&selinux_secmark_refcount);
4574 }
4575
4576 static void selinux_secmark_refcount_dec(void)
4577 {
4578         atomic_dec(&selinux_secmark_refcount);
4579 }
4580
4581 static void selinux_req_classify_flow(const struct request_sock *req,
4582                                       struct flowi *fl)
4583 {
4584         fl->flowi_secid = req->secid;
4585 }
4586
4587 static int selinux_tun_dev_alloc_security(void **security)
4588 {
4589         struct tun_security_struct *tunsec;
4590
4591         tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
4592         if (!tunsec)
4593                 return -ENOMEM;
4594         tunsec->sid = current_sid();
4595
4596         *security = tunsec;
4597         return 0;
4598 }
4599
4600 static void selinux_tun_dev_free_security(void *security)
4601 {
4602         kfree(security);
4603 }
4604
4605 static int selinux_tun_dev_create(void)
4606 {
4607         u32 sid = current_sid();
4608
4609         /* we aren't taking into account the "sockcreate" SID since the socket
4610          * that is being created here is not a socket in the traditional sense,
4611          * instead it is a private sock, accessible only to the kernel, and
4612          * representing a wide range of network traffic spanning multiple
4613          * connections unlike traditional sockets - check the TUN driver to
4614          * get a better understanding of why this socket is special */
4615
4616         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4617                             NULL);
4618 }
4619
4620 static int selinux_tun_dev_attach_queue(void *security)
4621 {
4622         struct tun_security_struct *tunsec = security;
4623
4624         return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
4625                             TUN_SOCKET__ATTACH_QUEUE, NULL);
4626 }
4627
4628 static int selinux_tun_dev_attach(struct sock *sk, void *security)
4629 {
4630         struct tun_security_struct *tunsec = security;
4631         struct sk_security_struct *sksec = sk->sk_security;
4632
4633         /* we don't currently perform any NetLabel based labeling here and it
4634          * isn't clear that we would want to do so anyway; while we could apply
4635          * labeling without the support of the TUN user the resulting labeled
4636          * traffic from the other end of the connection would almost certainly
4637          * cause confusion to the TUN user that had no idea network labeling
4638          * protocols were being used */
4639
4640         sksec->sid = tunsec->sid;
4641         sksec->sclass = SECCLASS_TUN_SOCKET;
4642
4643         return 0;
4644 }
4645
4646 static int selinux_tun_dev_open(void *security)
4647 {
4648         struct tun_security_struct *tunsec = security;
4649         u32 sid = current_sid();
4650         int err;
4651
4652         err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4653                            TUN_SOCKET__RELABELFROM, NULL);
4654         if (err)
4655                 return err;
4656         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4657                            TUN_SOCKET__RELABELTO, NULL);
4658         if (err)
4659                 return err;
4660         tunsec->sid = sid;
4661
4662         return 0;
4663 }
4664
4665 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4666 {
4667         int err = 0;
4668         u32 perm;
4669         struct nlmsghdr *nlh;
4670         struct sk_security_struct *sksec = sk->sk_security;
4671
4672         if (skb->len < NLMSG_HDRLEN) {
4673                 err = -EINVAL;
4674                 goto out;
4675         }
4676         nlh = nlmsg_hdr(skb);
4677
4678         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4679         if (err) {
4680                 if (err == -EINVAL) {
4681                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4682                                   "SELinux:  unrecognized netlink message"
4683                                   " type=%hu for sclass=%hu\n",
4684                                   nlh->nlmsg_type, sksec->sclass);
4685                         if (!selinux_enforcing || security_get_allow_unknown())
4686                                 err = 0;
4687                 }
4688
4689                 /* Ignore */
4690                 if (err == -ENOENT)
4691                         err = 0;
4692                 goto out;
4693         }
4694
4695         err = sock_has_perm(current, sk, perm);
4696 out:
4697         return err;
4698 }
4699
4700 #ifdef CONFIG_NETFILTER
4701
4702 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4703                                        u16 family)
4704 {
4705         int err;
4706         char *addrp;
4707         u32 peer_sid;
4708         struct common_audit_data ad;
4709         struct lsm_network_audit net = {0,};
4710         u8 secmark_active;
4711         u8 netlbl_active;
4712         u8 peerlbl_active;
4713
4714         if (!selinux_policycap_netpeer)
4715                 return NF_ACCEPT;
4716
4717         secmark_active = selinux_secmark_enabled();
4718         netlbl_active = netlbl_enabled();
4719         peerlbl_active = selinux_peerlbl_enabled();
4720         if (!secmark_active && !peerlbl_active)
4721                 return NF_ACCEPT;
4722
4723         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4724                 return NF_DROP;
4725
4726         ad.type = LSM_AUDIT_DATA_NET;
4727         ad.u.net = &net;
4728         ad.u.net->netif = ifindex;
4729         ad.u.net->family = family;
4730         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4731                 return NF_DROP;
4732
4733         if (peerlbl_active) {
4734                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4735                                                peer_sid, &ad);
4736                 if (err) {
4737                         selinux_netlbl_err(skb, err, 1);
4738                         return NF_DROP;
4739                 }
4740         }
4741
4742         if (secmark_active)
4743                 if (avc_has_perm(peer_sid, skb->secmark,
4744                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4745                         return NF_DROP;
4746
4747         if (netlbl_active)
4748                 /* we do this in the FORWARD path and not the POST_ROUTING
4749                  * path because we want to make sure we apply the necessary
4750                  * labeling before IPsec is applied so we can leverage AH
4751                  * protection */
4752                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4753                         return NF_DROP;
4754
4755         return NF_ACCEPT;
4756 }
4757
4758 static unsigned int selinux_ipv4_forward(const struct nf_hook_ops *ops,
4759                                          struct sk_buff *skb,
4760                                          const struct net_device *in,
4761                                          const struct net_device *out,
4762                                          int (*okfn)(struct sk_buff *))
4763 {
4764         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4765 }
4766
4767 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4768 static unsigned int selinux_ipv6_forward(const struct nf_hook_ops *ops,
4769                                          struct sk_buff *skb,
4770                                          const struct net_device *in,
4771                                          const struct net_device *out,
4772                                          int (*okfn)(struct sk_buff *))
4773 {
4774         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4775 }
4776 #endif  /* IPV6 */
4777
4778 static unsigned int selinux_ip_output(struct sk_buff *skb,
4779                                       u16 family)
4780 {
4781         struct sock *sk;
4782         u32 sid;
4783
4784         if (!netlbl_enabled())
4785                 return NF_ACCEPT;
4786
4787         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4788          * because we want to make sure we apply the necessary labeling
4789          * before IPsec is applied so we can leverage AH protection */
4790         sk = skb->sk;
4791         if (sk) {
4792                 struct sk_security_struct *sksec;
4793
4794                 if (sk->sk_state == TCP_LISTEN)
4795                         /* if the socket is the listening state then this
4796                          * packet is a SYN-ACK packet which means it needs to
4797                          * be labeled based on the connection/request_sock and
4798                          * not the parent socket.  unfortunately, we can't
4799                          * lookup the request_sock yet as it isn't queued on
4800                          * the parent socket until after the SYN-ACK is sent.
4801                          * the "solution" is to simply pass the packet as-is
4802                          * as any IP option based labeling should be copied
4803                          * from the initial connection request (in the IP
4804                          * layer).  it is far from ideal, but until we get a
4805                          * security label in the packet itself this is the
4806                          * best we can do. */
4807                         return NF_ACCEPT;
4808
4809                 /* standard practice, label using the parent socket */
4810                 sksec = sk->sk_security;
4811                 sid = sksec->sid;
4812         } else
4813                 sid = SECINITSID_KERNEL;
4814         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4815                 return NF_DROP;
4816
4817         return NF_ACCEPT;
4818 }
4819
4820 static unsigned int selinux_ipv4_output(const struct nf_hook_ops *ops,
4821                                         struct sk_buff *skb,
4822                                         const struct net_device *in,
4823                                         const struct net_device *out,
4824                                         int (*okfn)(struct sk_buff *))
4825 {
4826         return selinux_ip_output(skb, PF_INET);
4827 }
4828
4829 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4830                                                 int ifindex,
4831                                                 u16 family)
4832 {
4833         struct sock *sk = skb->sk;
4834         struct sk_security_struct *sksec;
4835         struct common_audit_data ad;
4836         struct lsm_network_audit net = {0,};
4837         char *addrp;
4838         u8 proto;
4839
4840         if (sk == NULL)
4841                 return NF_ACCEPT;
4842         sksec = sk->sk_security;
4843
4844         ad.type = LSM_AUDIT_DATA_NET;
4845         ad.u.net = &net;
4846         ad.u.net->netif = ifindex;
4847         ad.u.net->family = family;
4848         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4849                 return NF_DROP;
4850
4851         if (selinux_secmark_enabled())
4852                 if (avc_has_perm(sksec->sid, skb->secmark,
4853                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4854                         return NF_DROP_ERR(-ECONNREFUSED);
4855
4856         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4857                 return NF_DROP_ERR(-ECONNREFUSED);
4858
4859         return NF_ACCEPT;
4860 }
4861
4862 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4863                                          u16 family)
4864 {
4865         u32 secmark_perm;
4866         u32 peer_sid;
4867         struct sock *sk;
4868         struct common_audit_data ad;
4869         struct lsm_network_audit net = {0,};
4870         char *addrp;
4871         u8 secmark_active;
4872         u8 peerlbl_active;
4873
4874         /* If any sort of compatibility mode is enabled then handoff processing
4875          * to the selinux_ip_postroute_compat() function to deal with the
4876          * special handling.  We do this in an attempt to keep this function
4877          * as fast and as clean as possible. */
4878         if (!selinux_policycap_netpeer)
4879                 return selinux_ip_postroute_compat(skb, ifindex, family);
4880
4881         secmark_active = selinux_secmark_enabled();
4882         peerlbl_active = selinux_peerlbl_enabled();
4883         if (!secmark_active && !peerlbl_active)
4884                 return NF_ACCEPT;
4885
4886         sk = skb->sk;
4887
4888 #ifdef CONFIG_XFRM
4889         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4890          * packet transformation so allow the packet to pass without any checks
4891          * since we'll have another chance to perform access control checks
4892          * when the packet is on it's final way out.
4893          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4894          *       is NULL, in this case go ahead and apply access control.
4895          * NOTE: if this is a local socket (skb->sk != NULL) that is in the
4896          *       TCP listening state we cannot wait until the XFRM processing
4897          *       is done as we will miss out on the SA label if we do;
4898          *       unfortunately, this means more work, but it is only once per
4899          *       connection. */
4900         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
4901             !(sk != NULL && sk->sk_state == TCP_LISTEN))
4902                 return NF_ACCEPT;
4903 #endif
4904
4905         if (sk == NULL) {
4906                 /* Without an associated socket the packet is either coming
4907                  * from the kernel or it is being forwarded; check the packet
4908                  * to determine which and if the packet is being forwarded
4909                  * query the packet directly to determine the security label. */
4910                 if (skb->skb_iif) {
4911                         secmark_perm = PACKET__FORWARD_OUT;
4912                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4913                                 return NF_DROP;
4914                 } else {
4915                         secmark_perm = PACKET__SEND;
4916                         peer_sid = SECINITSID_KERNEL;
4917                 }
4918         } else if (sk->sk_state == TCP_LISTEN) {
4919                 /* Locally generated packet but the associated socket is in the
4920                  * listening state which means this is a SYN-ACK packet.  In
4921                  * this particular case the correct security label is assigned
4922                  * to the connection/request_sock but unfortunately we can't
4923                  * query the request_sock as it isn't queued on the parent
4924                  * socket until after the SYN-ACK packet is sent; the only
4925                  * viable choice is to regenerate the label like we do in
4926                  * selinux_inet_conn_request().  See also selinux_ip_output()
4927                  * for similar problems. */
4928                 u32 skb_sid;
4929                 struct sk_security_struct *sksec = sk->sk_security;
4930                 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
4931                         return NF_DROP;
4932                 /* At this point, if the returned skb peerlbl is SECSID_NULL
4933                  * and the packet has been through at least one XFRM
4934                  * transformation then we must be dealing with the "final"
4935                  * form of labeled IPsec packet; since we've already applied
4936                  * all of our access controls on this packet we can safely
4937                  * pass the packet. */
4938                 if (skb_sid == SECSID_NULL) {
4939                         switch (family) {
4940                         case PF_INET:
4941                                 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
4942                                         return NF_ACCEPT;
4943                                 break;
4944                         case PF_INET6:
4945                                 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
4946                                         return NF_ACCEPT;
4947                         default:
4948                                 return NF_DROP_ERR(-ECONNREFUSED);
4949                         }
4950                 }
4951                 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
4952                         return NF_DROP;
4953                 secmark_perm = PACKET__SEND;
4954         } else {
4955                 /* Locally generated packet, fetch the security label from the
4956                  * associated socket. */
4957                 struct sk_security_struct *sksec = sk->sk_security;
4958                 peer_sid = sksec->sid;
4959                 secmark_perm = PACKET__SEND;
4960         }
4961
4962         ad.type = LSM_AUDIT_DATA_NET;
4963         ad.u.net = &net;
4964         ad.u.net->netif = ifindex;
4965         ad.u.net->family = family;
4966         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4967                 return NF_DROP;
4968
4969         if (secmark_active)
4970                 if (avc_has_perm(peer_sid, skb->secmark,
4971                                  SECCLASS_PACKET, secmark_perm, &ad))
4972                         return NF_DROP_ERR(-ECONNREFUSED);
4973
4974         if (peerlbl_active) {
4975                 u32 if_sid;
4976                 u32 node_sid;
4977
4978                 if (sel_netif_sid(ifindex, &if_sid))
4979                         return NF_DROP;
4980                 if (avc_has_perm(peer_sid, if_sid,
4981                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4982                         return NF_DROP_ERR(-ECONNREFUSED);
4983
4984                 if (sel_netnode_sid(addrp, family, &node_sid))
4985                         return NF_DROP;
4986                 if (avc_has_perm(peer_sid, node_sid,
4987                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4988                         return NF_DROP_ERR(-ECONNREFUSED);
4989         }
4990
4991         return NF_ACCEPT;
4992 }
4993
4994 static unsigned int selinux_ipv4_postroute(const struct nf_hook_ops *ops,
4995                                            struct sk_buff *skb,
4996                                            const struct net_device *in,
4997                                            const struct net_device *out,
4998                                            int (*okfn)(struct sk_buff *))
4999 {
5000         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
5001 }
5002
5003 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5004 static unsigned int selinux_ipv6_postroute(const struct nf_hook_ops *ops,
5005                                            struct sk_buff *skb,
5006                                            const struct net_device *in,
5007                                            const struct net_device *out,
5008                                            int (*okfn)(struct sk_buff *))
5009 {
5010         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
5011 }
5012 #endif  /* IPV6 */
5013
5014 #endif  /* CONFIG_NETFILTER */
5015
5016 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5017 {
5018         int err;
5019
5020         err = cap_netlink_send(sk, skb);
5021         if (err)
5022                 return err;
5023
5024         return selinux_nlmsg_perm(sk, skb);
5025 }
5026
5027 static int ipc_alloc_security(struct task_struct *task,
5028                               struct kern_ipc_perm *perm,
5029                               u16 sclass)
5030 {
5031         struct ipc_security_struct *isec;
5032         u32 sid;
5033
5034         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
5035         if (!isec)
5036                 return -ENOMEM;
5037
5038         sid = task_sid(task);
5039         isec->sclass = sclass;
5040         isec->sid = sid;
5041         perm->security = isec;
5042
5043         return 0;
5044 }
5045
5046 static void ipc_free_security(struct kern_ipc_perm *perm)
5047 {
5048         struct ipc_security_struct *isec = perm->security;
5049         perm->security = NULL;
5050         kfree(isec);
5051 }
5052
5053 static int msg_msg_alloc_security(struct msg_msg *msg)
5054 {
5055         struct msg_security_struct *msec;
5056
5057         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
5058         if (!msec)
5059                 return -ENOMEM;
5060
5061         msec->sid = SECINITSID_UNLABELED;
5062         msg->security = msec;
5063
5064         return 0;
5065 }
5066
5067 static void msg_msg_free_security(struct msg_msg *msg)
5068 {
5069         struct msg_security_struct *msec = msg->security;
5070
5071         msg->security = NULL;
5072         kfree(msec);
5073 }
5074
5075 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5076                         u32 perms)
5077 {
5078         struct ipc_security_struct *isec;
5079         struct common_audit_data ad;
5080         u32 sid = current_sid();
5081
5082         isec = ipc_perms->security;
5083
5084         ad.type = LSM_AUDIT_DATA_IPC;
5085         ad.u.ipc_id = ipc_perms->key;
5086
5087         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
5088 }
5089
5090 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5091 {
5092         return msg_msg_alloc_security(msg);
5093 }
5094
5095 static void selinux_msg_msg_free_security(struct msg_msg *msg)
5096 {
5097         msg_msg_free_security(msg);
5098 }
5099
5100 /* message queue security operations */
5101 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
5102 {
5103         struct ipc_security_struct *isec;
5104         struct common_audit_data ad;
5105         u32 sid = current_sid();
5106         int rc;
5107
5108         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
5109         if (rc)
5110                 return rc;
5111
5112         isec = msq->q_perm.security;
5113
5114         ad.type = LSM_AUDIT_DATA_IPC;
5115         ad.u.ipc_id = msq->q_perm.key;
5116
5117         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5118                           MSGQ__CREATE, &ad);
5119         if (rc) {
5120                 ipc_free_security(&msq->q_perm);
5121                 return rc;
5122         }
5123         return 0;
5124 }
5125
5126 static void selinux_msg_queue_free_security(struct msg_queue *msq)
5127 {
5128         ipc_free_security(&msq->q_perm);
5129 }
5130
5131 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
5132 {
5133         struct ipc_security_struct *isec;
5134         struct common_audit_data ad;
5135         u32 sid = current_sid();
5136
5137         isec = msq->q_perm.security;
5138
5139         ad.type = LSM_AUDIT_DATA_IPC;
5140         ad.u.ipc_id = msq->q_perm.key;
5141
5142         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5143                             MSGQ__ASSOCIATE, &ad);
5144 }
5145
5146 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
5147 {
5148         int err;
5149         int perms;
5150
5151         switch (cmd) {
5152         case IPC_INFO:
5153         case MSG_INFO:
5154                 /* No specific object, just general system-wide information. */
5155                 return task_has_system(current, SYSTEM__IPC_INFO);
5156         case IPC_STAT:
5157         case MSG_STAT:
5158                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5159                 break;
5160         case IPC_SET:
5161                 perms = MSGQ__SETATTR;
5162                 break;
5163         case IPC_RMID:
5164                 perms = MSGQ__DESTROY;
5165                 break;
5166         default:
5167                 return 0;
5168         }
5169
5170         err = ipc_has_perm(&msq->q_perm, perms);
5171         return err;
5172 }
5173
5174 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
5175 {
5176         struct ipc_security_struct *isec;
5177         struct msg_security_struct *msec;
5178         struct common_audit_data ad;
5179         u32 sid = current_sid();
5180         int rc;
5181
5182         isec = msq->q_perm.security;
5183         msec = msg->security;
5184
5185         /*
5186          * First time through, need to assign label to the message
5187          */
5188         if (msec->sid == SECINITSID_UNLABELED) {
5189                 /*
5190                  * Compute new sid based on current process and
5191                  * message queue this message will be stored in
5192                  */
5193                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5194                                              NULL, &msec->sid);
5195                 if (rc)
5196                         return rc;
5197         }
5198
5199         ad.type = LSM_AUDIT_DATA_IPC;
5200         ad.u.ipc_id = msq->q_perm.key;
5201
5202         /* Can this process write to the queue? */
5203         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5204                           MSGQ__WRITE, &ad);
5205         if (!rc)
5206                 /* Can this process send the message */
5207                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5208                                   MSG__SEND, &ad);
5209         if (!rc)
5210                 /* Can the message be put in the queue? */
5211                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5212                                   MSGQ__ENQUEUE, &ad);
5213
5214         return rc;
5215 }
5216
5217 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5218                                     struct task_struct *target,
5219                                     long type, int mode)
5220 {
5221         struct ipc_security_struct *isec;
5222         struct msg_security_struct *msec;
5223         struct common_audit_data ad;
5224         u32 sid = task_sid(target);
5225         int rc;
5226
5227         isec = msq->q_perm.security;
5228         msec = msg->security;
5229
5230         ad.type = LSM_AUDIT_DATA_IPC;
5231         ad.u.ipc_id = msq->q_perm.key;
5232
5233         rc = avc_has_perm(sid, isec->sid,
5234                           SECCLASS_MSGQ, MSGQ__READ, &ad);
5235         if (!rc)
5236                 rc = avc_has_perm(sid, msec->sid,
5237                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
5238         return rc;
5239 }
5240
5241 /* Shared Memory security operations */
5242 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5243 {
5244         struct ipc_security_struct *isec;
5245         struct common_audit_data ad;
5246         u32 sid = current_sid();
5247         int rc;
5248
5249         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5250         if (rc)
5251                 return rc;
5252
5253         isec = shp->shm_perm.security;
5254
5255         ad.type = LSM_AUDIT_DATA_IPC;
5256         ad.u.ipc_id = shp->shm_perm.key;
5257
5258         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5259                           SHM__CREATE, &ad);
5260         if (rc) {
5261                 ipc_free_security(&shp->shm_perm);
5262                 return rc;
5263         }
5264         return 0;
5265 }
5266
5267 static void selinux_shm_free_security(struct shmid_kernel *shp)
5268 {
5269         ipc_free_security(&shp->shm_perm);
5270 }
5271
5272 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5273 {
5274         struct ipc_security_struct *isec;
5275         struct common_audit_data ad;
5276         u32 sid = current_sid();
5277
5278         isec = shp->shm_perm.security;
5279
5280         ad.type = LSM_AUDIT_DATA_IPC;
5281         ad.u.ipc_id = shp->shm_perm.key;
5282
5283         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5284                             SHM__ASSOCIATE, &ad);
5285 }
5286
5287 /* Note, at this point, shp is locked down */
5288 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5289 {
5290         int perms;
5291         int err;
5292
5293         switch (cmd) {
5294         case IPC_INFO:
5295         case SHM_INFO:
5296                 /* No specific object, just general system-wide information. */
5297                 return task_has_system(current, SYSTEM__IPC_INFO);
5298         case IPC_STAT:
5299         case SHM_STAT:
5300                 perms = SHM__GETATTR | SHM__ASSOCIATE;
5301                 break;
5302         case IPC_SET:
5303                 perms = SHM__SETATTR;
5304                 break;
5305         case SHM_LOCK:
5306         case SHM_UNLOCK:
5307                 perms = SHM__LOCK;
5308                 break;
5309         case IPC_RMID:
5310                 perms = SHM__DESTROY;
5311                 break;
5312         default:
5313                 return 0;
5314         }
5315
5316         err = ipc_has_perm(&shp->shm_perm, perms);
5317         return err;
5318 }
5319
5320 static int selinux_shm_shmat(struct shmid_kernel *shp,
5321                              char __user *shmaddr, int shmflg)
5322 {
5323         u32 perms;
5324
5325         if (shmflg & SHM_RDONLY)
5326                 perms = SHM__READ;
5327         else
5328                 perms = SHM__READ | SHM__WRITE;
5329
5330         return ipc_has_perm(&shp->shm_perm, perms);
5331 }
5332
5333 /* Semaphore security operations */
5334 static int selinux_sem_alloc_security(struct sem_array *sma)
5335 {
5336         struct ipc_security_struct *isec;
5337         struct common_audit_data ad;
5338         u32 sid = current_sid();
5339         int rc;
5340
5341         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5342         if (rc)
5343                 return rc;
5344
5345         isec = sma->sem_perm.security;
5346
5347         ad.type = LSM_AUDIT_DATA_IPC;
5348         ad.u.ipc_id = sma->sem_perm.key;
5349
5350         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5351                           SEM__CREATE, &ad);
5352         if (rc) {
5353                 ipc_free_security(&sma->sem_perm);
5354                 return rc;
5355         }
5356         return 0;
5357 }
5358
5359 static void selinux_sem_free_security(struct sem_array *sma)
5360 {
5361         ipc_free_security(&sma->sem_perm);
5362 }
5363
5364 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5365 {
5366         struct ipc_security_struct *isec;
5367         struct common_audit_data ad;
5368         u32 sid = current_sid();
5369
5370         isec = sma->sem_perm.security;
5371
5372         ad.type = LSM_AUDIT_DATA_IPC;
5373         ad.u.ipc_id = sma->sem_perm.key;
5374
5375         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5376                             SEM__ASSOCIATE, &ad);
5377 }
5378
5379 /* Note, at this point, sma is locked down */
5380 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5381 {
5382         int err;
5383         u32 perms;
5384
5385         switch (cmd) {
5386         case IPC_INFO:
5387         case SEM_INFO:
5388                 /* No specific object, just general system-wide information. */
5389                 return task_has_system(current, SYSTEM__IPC_INFO);
5390         case GETPID:
5391         case GETNCNT:
5392         case GETZCNT:
5393                 perms = SEM__GETATTR;
5394                 break;
5395         case GETVAL:
5396         case GETALL:
5397                 perms = SEM__READ;
5398                 break;
5399         case SETVAL:
5400         case SETALL:
5401                 perms = SEM__WRITE;
5402                 break;
5403         case IPC_RMID:
5404                 perms = SEM__DESTROY;
5405                 break;
5406         case IPC_SET:
5407                 perms = SEM__SETATTR;
5408                 break;
5409         case IPC_STAT:
5410         case SEM_STAT:
5411                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5412                 break;
5413         default:
5414                 return 0;
5415         }
5416
5417         err = ipc_has_perm(&sma->sem_perm, perms);
5418         return err;
5419 }
5420
5421 static int selinux_sem_semop(struct sem_array *sma,
5422                              struct sembuf *sops, unsigned nsops, int alter)
5423 {
5424         u32 perms;
5425
5426         if (alter)
5427                 perms = SEM__READ | SEM__WRITE;
5428         else
5429                 perms = SEM__READ;
5430
5431         return ipc_has_perm(&sma->sem_perm, perms);
5432 }
5433
5434 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5435 {
5436         u32 av = 0;
5437
5438         av = 0;
5439         if (flag & S_IRUGO)
5440                 av |= IPC__UNIX_READ;
5441         if (flag & S_IWUGO)
5442                 av |= IPC__UNIX_WRITE;
5443
5444         if (av == 0)
5445                 return 0;
5446
5447         return ipc_has_perm(ipcp, av);
5448 }
5449
5450 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5451 {
5452         struct ipc_security_struct *isec = ipcp->security;
5453         *secid = isec->sid;
5454 }
5455
5456 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5457 {
5458         if (inode)
5459                 inode_doinit_with_dentry(inode, dentry);
5460 }
5461
5462 static int selinux_getprocattr(struct task_struct *p,
5463                                char *name, char **value)
5464 {
5465         const struct task_security_struct *__tsec;
5466         u32 sid;
5467         int error;
5468         unsigned len;
5469
5470         if (current != p) {
5471                 error = current_has_perm(p, PROCESS__GETATTR);
5472                 if (error)
5473                         return error;
5474         }
5475
5476         rcu_read_lock();
5477         __tsec = __task_cred(p)->security;
5478
5479         if (!strcmp(name, "current"))
5480                 sid = __tsec->sid;
5481         else if (!strcmp(name, "prev"))
5482                 sid = __tsec->osid;
5483         else if (!strcmp(name, "exec"))
5484                 sid = __tsec->exec_sid;
5485         else if (!strcmp(name, "fscreate"))
5486                 sid = __tsec->create_sid;
5487         else if (!strcmp(name, "keycreate"))
5488                 sid = __tsec->keycreate_sid;
5489         else if (!strcmp(name, "sockcreate"))
5490                 sid = __tsec->sockcreate_sid;
5491         else
5492                 goto invalid;
5493         rcu_read_unlock();
5494
5495         if (!sid)
5496                 return 0;
5497
5498         error = security_sid_to_context(sid, value, &len);
5499         if (error)
5500                 return error;
5501         return len;
5502
5503 invalid:
5504         rcu_read_unlock();
5505         return -EINVAL;
5506 }
5507
5508 static int selinux_setprocattr(struct task_struct *p,
5509                                char *name, void *value, size_t size)
5510 {
5511         struct task_security_struct *tsec;
5512         struct task_struct *tracer;
5513         struct cred *new;
5514         u32 sid = 0, ptsid;
5515         int error;
5516         char *str = value;
5517
5518         if (current != p) {
5519                 /* SELinux only allows a process to change its own
5520                    security attributes. */
5521                 return -EACCES;
5522         }
5523
5524         /*
5525          * Basic control over ability to set these attributes at all.
5526          * current == p, but we'll pass them separately in case the
5527          * above restriction is ever removed.
5528          */
5529         if (!strcmp(name, "exec"))
5530                 error = current_has_perm(p, PROCESS__SETEXEC);
5531         else if (!strcmp(name, "fscreate"))
5532                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5533         else if (!strcmp(name, "keycreate"))
5534                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5535         else if (!strcmp(name, "sockcreate"))
5536                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5537         else if (!strcmp(name, "current"))
5538                 error = current_has_perm(p, PROCESS__SETCURRENT);
5539         else
5540                 error = -EINVAL;
5541         if (error)
5542                 return error;
5543
5544         /* Obtain a SID for the context, if one was specified. */
5545         if (size && str[1] && str[1] != '\n') {
5546                 if (str[size-1] == '\n') {
5547                         str[size-1] = 0;
5548                         size--;
5549                 }
5550                 error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5551                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5552                         if (!capable(CAP_MAC_ADMIN)) {
5553                                 struct audit_buffer *ab;
5554                                 size_t audit_size;
5555
5556                                 /* We strip a nul only if it is at the end, otherwise the
5557                                  * context contains a nul and we should audit that */
5558                                 if (str[size - 1] == '\0')
5559                                         audit_size = size - 1;
5560                                 else
5561                                         audit_size = size;
5562                                 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5563                                 audit_log_format(ab, "op=fscreate invalid_context=");
5564                                 audit_log_n_untrustedstring(ab, value, audit_size);
5565                                 audit_log_end(ab);
5566
5567                                 return error;
5568                         }
5569                         error = security_context_to_sid_force(value, size,
5570                                                               &sid);
5571                 }
5572                 if (error)
5573                         return error;
5574         }
5575
5576         new = prepare_creds();
5577         if (!new)
5578                 return -ENOMEM;
5579
5580         /* Permission checking based on the specified context is
5581            performed during the actual operation (execve,
5582            open/mkdir/...), when we know the full context of the
5583            operation.  See selinux_bprm_set_creds for the execve
5584            checks and may_create for the file creation checks. The
5585            operation will then fail if the context is not permitted. */
5586         tsec = new->security;
5587         if (!strcmp(name, "exec")) {
5588                 tsec->exec_sid = sid;
5589         } else if (!strcmp(name, "fscreate")) {
5590                 tsec->create_sid = sid;
5591         } else if (!strcmp(name, "keycreate")) {
5592                 error = may_create_key(sid, p);
5593                 if (error)
5594                         goto abort_change;
5595                 tsec->keycreate_sid = sid;
5596         } else if (!strcmp(name, "sockcreate")) {
5597                 tsec->sockcreate_sid = sid;
5598         } else if (!strcmp(name, "current")) {
5599                 error = -EINVAL;
5600                 if (sid == 0)
5601                         goto abort_change;
5602
5603                 /* Only allow single threaded processes to change context */
5604                 error = -EPERM;
5605                 if (!current_is_single_threaded()) {
5606                         error = security_bounded_transition(tsec->sid, sid);
5607                         if (error)
5608                                 goto abort_change;
5609                 }
5610
5611                 /* Check permissions for the transition. */
5612                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5613                                      PROCESS__DYNTRANSITION, NULL);
5614                 if (error)
5615                         goto abort_change;
5616
5617                 /* Check for ptracing, and update the task SID if ok.
5618                    Otherwise, leave SID unchanged and fail. */
5619                 ptsid = 0;
5620                 rcu_read_lock();
5621                 tracer = ptrace_parent(p);
5622                 if (tracer)
5623                         ptsid = task_sid(tracer);
5624                 rcu_read_unlock();
5625
5626                 if (tracer) {
5627                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5628                                              PROCESS__PTRACE, NULL);
5629                         if (error)
5630                                 goto abort_change;
5631                 }
5632
5633                 tsec->sid = sid;
5634         } else {
5635                 error = -EINVAL;
5636                 goto abort_change;
5637         }
5638
5639         commit_creds(new);
5640         return size;
5641
5642 abort_change:
5643         abort_creds(new);
5644         return error;
5645 }
5646
5647 static int selinux_ismaclabel(const char *name)
5648 {
5649         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
5650 }
5651
5652 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5653 {
5654         return security_sid_to_context(secid, secdata, seclen);
5655 }
5656
5657 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5658 {
5659         return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
5660 }
5661
5662 static void selinux_release_secctx(char *secdata, u32 seclen)
5663 {
5664         kfree(secdata);
5665 }
5666
5667 /*
5668  *      called with inode->i_mutex locked
5669  */
5670 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5671 {
5672         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5673 }
5674
5675 /*
5676  *      called with inode->i_mutex locked
5677  */
5678 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5679 {
5680         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5681 }
5682
5683 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5684 {
5685         int len = 0;
5686         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5687                                                 ctx, true);
5688         if (len < 0)
5689                 return len;
5690         *ctxlen = len;
5691         return 0;
5692 }
5693 #ifdef CONFIG_KEYS
5694
5695 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5696                              unsigned long flags)
5697 {
5698         const struct task_security_struct *tsec;
5699         struct key_security_struct *ksec;
5700
5701         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5702         if (!ksec)
5703                 return -ENOMEM;
5704
5705         tsec = cred->security;
5706         if (tsec->keycreate_sid)
5707                 ksec->sid = tsec->keycreate_sid;
5708         else
5709                 ksec->sid = tsec->sid;
5710
5711         k->security = ksec;
5712         return 0;
5713 }
5714
5715 static void selinux_key_free(struct key *k)
5716 {
5717         struct key_security_struct *ksec = k->security;
5718
5719         k->security = NULL;
5720         kfree(ksec);
5721 }
5722
5723 static int selinux_key_permission(key_ref_t key_ref,
5724                                   const struct cred *cred,
5725                                   key_perm_t perm)
5726 {
5727         struct key *key;
5728         struct key_security_struct *ksec;
5729         u32 sid;
5730
5731         /* if no specific permissions are requested, we skip the
5732            permission check. No serious, additional covert channels
5733            appear to be created. */
5734         if (perm == 0)
5735                 return 0;
5736
5737         sid = cred_sid(cred);
5738
5739         key = key_ref_to_ptr(key_ref);
5740         ksec = key->security;
5741
5742         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5743 }
5744
5745 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5746 {
5747         struct key_security_struct *ksec = key->security;
5748         char *context = NULL;
5749         unsigned len;
5750         int rc;
5751
5752         rc = security_sid_to_context(ksec->sid, &context, &len);
5753         if (!rc)
5754                 rc = len;
5755         *_buffer = context;
5756         return rc;
5757 }
5758
5759 #endif
5760
5761 static struct security_operations selinux_ops = {
5762         .name =                         "selinux",
5763
5764         .ptrace_access_check =          selinux_ptrace_access_check,
5765         .ptrace_traceme =               selinux_ptrace_traceme,
5766         .capget =                       selinux_capget,
5767         .capset =                       selinux_capset,
5768         .capable =                      selinux_capable,
5769         .quotactl =                     selinux_quotactl,
5770         .quota_on =                     selinux_quota_on,
5771         .syslog =                       selinux_syslog,
5772         .vm_enough_memory =             selinux_vm_enough_memory,
5773
5774         .netlink_send =                 selinux_netlink_send,
5775
5776         .bprm_set_creds =               selinux_bprm_set_creds,
5777         .bprm_committing_creds =        selinux_bprm_committing_creds,
5778         .bprm_committed_creds =         selinux_bprm_committed_creds,
5779         .bprm_secureexec =              selinux_bprm_secureexec,
5780
5781         .sb_alloc_security =            selinux_sb_alloc_security,
5782         .sb_free_security =             selinux_sb_free_security,
5783         .sb_copy_data =                 selinux_sb_copy_data,
5784         .sb_remount =                   selinux_sb_remount,
5785         .sb_kern_mount =                selinux_sb_kern_mount,
5786         .sb_show_options =              selinux_sb_show_options,
5787         .sb_statfs =                    selinux_sb_statfs,
5788         .sb_mount =                     selinux_mount,
5789         .sb_umount =                    selinux_umount,
5790         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5791         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5792         .sb_parse_opts_str =            selinux_parse_opts_str,
5793
5794         .dentry_init_security =         selinux_dentry_init_security,
5795
5796         .inode_alloc_security =         selinux_inode_alloc_security,
5797         .inode_free_security =          selinux_inode_free_security,
5798         .inode_init_security =          selinux_inode_init_security,
5799         .inode_create =                 selinux_inode_create,
5800         .inode_link =                   selinux_inode_link,
5801         .inode_unlink =                 selinux_inode_unlink,
5802         .inode_symlink =                selinux_inode_symlink,
5803         .inode_mkdir =                  selinux_inode_mkdir,
5804         .inode_rmdir =                  selinux_inode_rmdir,
5805         .inode_mknod =                  selinux_inode_mknod,
5806         .inode_rename =                 selinux_inode_rename,
5807         .inode_readlink =               selinux_inode_readlink,
5808         .inode_follow_link =            selinux_inode_follow_link,
5809         .inode_permission =             selinux_inode_permission,
5810         .inode_setattr =                selinux_inode_setattr,
5811         .inode_getattr =                selinux_inode_getattr,
5812         .inode_setxattr =               selinux_inode_setxattr,
5813         .inode_post_setxattr =          selinux_inode_post_setxattr,
5814         .inode_getxattr =               selinux_inode_getxattr,
5815         .inode_listxattr =              selinux_inode_listxattr,
5816         .inode_removexattr =            selinux_inode_removexattr,
5817         .inode_getsecurity =            selinux_inode_getsecurity,
5818         .inode_setsecurity =            selinux_inode_setsecurity,
5819         .inode_listsecurity =           selinux_inode_listsecurity,
5820         .inode_getsecid =               selinux_inode_getsecid,
5821
5822         .file_permission =              selinux_file_permission,
5823         .file_alloc_security =          selinux_file_alloc_security,
5824         .file_free_security =           selinux_file_free_security,
5825         .file_ioctl =                   selinux_file_ioctl,
5826         .mmap_file =                    selinux_mmap_file,
5827         .mmap_addr =                    selinux_mmap_addr,
5828         .file_mprotect =                selinux_file_mprotect,
5829         .file_lock =                    selinux_file_lock,
5830         .file_fcntl =                   selinux_file_fcntl,
5831         .file_set_fowner =              selinux_file_set_fowner,
5832         .file_send_sigiotask =          selinux_file_send_sigiotask,
5833         .file_receive =                 selinux_file_receive,
5834
5835         .file_open =                    selinux_file_open,
5836
5837         .task_create =                  selinux_task_create,
5838         .cred_alloc_blank =             selinux_cred_alloc_blank,
5839         .cred_free =                    selinux_cred_free,
5840         .cred_prepare =                 selinux_cred_prepare,
5841         .cred_transfer =                selinux_cred_transfer,
5842         .kernel_act_as =                selinux_kernel_act_as,
5843         .kernel_create_files_as =       selinux_kernel_create_files_as,
5844         .kernel_module_request =        selinux_kernel_module_request,
5845         .task_setpgid =                 selinux_task_setpgid,
5846         .task_getpgid =                 selinux_task_getpgid,
5847         .task_getsid =                  selinux_task_getsid,
5848         .task_getsecid =                selinux_task_getsecid,
5849         .task_setnice =                 selinux_task_setnice,
5850         .task_setioprio =               selinux_task_setioprio,
5851         .task_getioprio =               selinux_task_getioprio,
5852         .task_setrlimit =               selinux_task_setrlimit,
5853         .task_setscheduler =            selinux_task_setscheduler,
5854         .task_getscheduler =            selinux_task_getscheduler,
5855         .task_movememory =              selinux_task_movememory,
5856         .task_kill =                    selinux_task_kill,
5857         .task_wait =                    selinux_task_wait,
5858         .task_to_inode =                selinux_task_to_inode,
5859
5860         .ipc_permission =               selinux_ipc_permission,
5861         .ipc_getsecid =                 selinux_ipc_getsecid,
5862
5863         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5864         .msg_msg_free_security =        selinux_msg_msg_free_security,
5865
5866         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5867         .msg_queue_free_security =      selinux_msg_queue_free_security,
5868         .msg_queue_associate =          selinux_msg_queue_associate,
5869         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5870         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5871         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5872
5873         .shm_alloc_security =           selinux_shm_alloc_security,
5874         .shm_free_security =            selinux_shm_free_security,
5875         .shm_associate =                selinux_shm_associate,
5876         .shm_shmctl =                   selinux_shm_shmctl,
5877         .shm_shmat =                    selinux_shm_shmat,
5878
5879         .sem_alloc_security =           selinux_sem_alloc_security,
5880         .sem_free_security =            selinux_sem_free_security,
5881         .sem_associate =                selinux_sem_associate,
5882         .sem_semctl =                   selinux_sem_semctl,
5883         .sem_semop =                    selinux_sem_semop,
5884
5885         .d_instantiate =                selinux_d_instantiate,
5886
5887         .getprocattr =                  selinux_getprocattr,
5888         .setprocattr =                  selinux_setprocattr,
5889
5890         .ismaclabel =                   selinux_ismaclabel,
5891         .secid_to_secctx =              selinux_secid_to_secctx,
5892         .secctx_to_secid =              selinux_secctx_to_secid,
5893         .release_secctx =               selinux_release_secctx,
5894         .inode_notifysecctx =           selinux_inode_notifysecctx,
5895         .inode_setsecctx =              selinux_inode_setsecctx,
5896         .inode_getsecctx =              selinux_inode_getsecctx,
5897
5898         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5899         .unix_may_send =                selinux_socket_unix_may_send,
5900
5901         .socket_create =                selinux_socket_create,
5902         .socket_post_create =           selinux_socket_post_create,
5903         .socket_bind =                  selinux_socket_bind,
5904         .socket_connect =               selinux_socket_connect,
5905         .socket_listen =                selinux_socket_listen,
5906         .socket_accept =                selinux_socket_accept,
5907         .socket_sendmsg =               selinux_socket_sendmsg,
5908         .socket_recvmsg =               selinux_socket_recvmsg,
5909         .socket_getsockname =           selinux_socket_getsockname,
5910         .socket_getpeername =           selinux_socket_getpeername,
5911         .socket_getsockopt =            selinux_socket_getsockopt,
5912         .socket_setsockopt =            selinux_socket_setsockopt,
5913         .socket_shutdown =              selinux_socket_shutdown,
5914         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5915         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5916         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5917         .sk_alloc_security =            selinux_sk_alloc_security,
5918         .sk_free_security =             selinux_sk_free_security,
5919         .sk_clone_security =            selinux_sk_clone_security,
5920         .sk_getsecid =                  selinux_sk_getsecid,
5921         .sock_graft =                   selinux_sock_graft,
5922         .inet_conn_request =            selinux_inet_conn_request,
5923         .inet_csk_clone =               selinux_inet_csk_clone,
5924         .inet_conn_established =        selinux_inet_conn_established,
5925         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
5926         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
5927         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
5928         .req_classify_flow =            selinux_req_classify_flow,
5929         .tun_dev_alloc_security =       selinux_tun_dev_alloc_security,
5930         .tun_dev_free_security =        selinux_tun_dev_free_security,
5931         .tun_dev_create =               selinux_tun_dev_create,
5932         .tun_dev_attach_queue =         selinux_tun_dev_attach_queue,
5933         .tun_dev_attach =               selinux_tun_dev_attach,
5934         .tun_dev_open =                 selinux_tun_dev_open,
5935         .skb_owned_by =                 selinux_skb_owned_by,
5936
5937 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5938         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5939         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5940         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5941         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5942         .xfrm_state_alloc =             selinux_xfrm_state_alloc,
5943         .xfrm_state_alloc_acquire =     selinux_xfrm_state_alloc_acquire,
5944         .xfrm_state_free_security =     selinux_xfrm_state_free,
5945         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5946         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5947         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5948         .xfrm_decode_session =          selinux_xfrm_decode_session,
5949 #endif
5950
5951 #ifdef CONFIG_KEYS
5952         .key_alloc =                    selinux_key_alloc,
5953         .key_free =                     selinux_key_free,
5954         .key_permission =               selinux_key_permission,
5955         .key_getsecurity =              selinux_key_getsecurity,
5956 #endif
5957
5958 #ifdef CONFIG_AUDIT
5959         .audit_rule_init =              selinux_audit_rule_init,
5960         .audit_rule_known =             selinux_audit_rule_known,
5961         .audit_rule_match =             selinux_audit_rule_match,
5962         .audit_rule_free =              selinux_audit_rule_free,
5963 #endif
5964 };
5965
5966 static __init int selinux_init(void)
5967 {
5968         if (!security_module_enable(&selinux_ops)) {
5969                 selinux_enabled = 0;
5970                 return 0;
5971         }
5972
5973         if (!selinux_enabled) {
5974                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5975                 return 0;
5976         }
5977
5978         printk(KERN_INFO "SELinux:  Initializing.\n");
5979
5980         /* Set the security state for the initial task. */
5981         cred_init_security();
5982
5983         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5984
5985         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5986                                             sizeof(struct inode_security_struct),
5987                                             0, SLAB_PANIC, NULL);
5988         avc_init();
5989
5990         if (register_security(&selinux_ops))
5991                 panic("SELinux: Unable to register with kernel.\n");
5992
5993         if (selinux_enforcing)
5994                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5995         else
5996                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5997
5998         return 0;
5999 }
6000
6001 static void delayed_superblock_init(struct super_block *sb, void *unused)
6002 {
6003         superblock_doinit(sb, NULL);
6004 }
6005
6006 void selinux_complete_init(void)
6007 {
6008         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
6009
6010         /* Set up any superblocks initialized prior to the policy load. */
6011         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
6012         iterate_supers(delayed_superblock_init, NULL);
6013 }
6014
6015 /* SELinux requires early initialization in order to label
6016    all processes and objects when they are created. */
6017 security_initcall(selinux_init);
6018
6019 #if defined(CONFIG_NETFILTER)
6020
6021 static struct nf_hook_ops selinux_ipv4_ops[] = {
6022         {
6023                 .hook =         selinux_ipv4_postroute,
6024                 .owner =        THIS_MODULE,
6025                 .pf =           NFPROTO_IPV4,
6026                 .hooknum =      NF_INET_POST_ROUTING,
6027                 .priority =     NF_IP_PRI_SELINUX_LAST,
6028         },
6029         {
6030                 .hook =         selinux_ipv4_forward,
6031                 .owner =        THIS_MODULE,
6032                 .pf =           NFPROTO_IPV4,
6033                 .hooknum =      NF_INET_FORWARD,
6034                 .priority =     NF_IP_PRI_SELINUX_FIRST,
6035         },
6036         {
6037                 .hook =         selinux_ipv4_output,
6038                 .owner =        THIS_MODULE,
6039                 .pf =           NFPROTO_IPV4,
6040                 .hooknum =      NF_INET_LOCAL_OUT,
6041                 .priority =     NF_IP_PRI_SELINUX_FIRST,
6042         }
6043 };
6044
6045 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6046
6047 static struct nf_hook_ops selinux_ipv6_ops[] = {
6048         {
6049                 .hook =         selinux_ipv6_postroute,
6050                 .owner =        THIS_MODULE,
6051                 .pf =           NFPROTO_IPV6,
6052                 .hooknum =      NF_INET_POST_ROUTING,
6053                 .priority =     NF_IP6_PRI_SELINUX_LAST,
6054         },
6055         {
6056                 .hook =         selinux_ipv6_forward,
6057                 .owner =        THIS_MODULE,
6058                 .pf =           NFPROTO_IPV6,
6059                 .hooknum =      NF_INET_FORWARD,
6060                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
6061         }
6062 };
6063
6064 #endif  /* IPV6 */
6065
6066 static int __init selinux_nf_ip_init(void)
6067 {
6068         int err = 0;
6069
6070         if (!selinux_enabled)
6071                 goto out;
6072
6073         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
6074
6075         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
6076         if (err)
6077                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
6078
6079 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6080         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
6081         if (err)
6082                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
6083 #endif  /* IPV6 */
6084
6085 out:
6086         return err;
6087 }
6088
6089 __initcall(selinux_nf_ip_init);
6090
6091 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
6092 static void selinux_nf_ip_exit(void)
6093 {
6094         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
6095
6096         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
6097 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
6098         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
6099 #endif  /* IPV6 */
6100 }
6101 #endif
6102
6103 #else /* CONFIG_NETFILTER */
6104
6105 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
6106 #define selinux_nf_ip_exit()
6107 #endif
6108
6109 #endif /* CONFIG_NETFILTER */
6110
6111 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
6112 static int selinux_disabled;
6113
6114 int selinux_disable(void)
6115 {
6116         if (ss_initialized) {
6117                 /* Not permitted after initial policy load. */
6118                 return -EINVAL;
6119         }
6120
6121         if (selinux_disabled) {
6122                 /* Only do this once. */
6123                 return -EINVAL;
6124         }
6125
6126         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
6127
6128         selinux_disabled = 1;
6129         selinux_enabled = 0;
6130
6131         reset_security_ops();
6132
6133         /* Try to destroy the avc node cache */
6134         avc_disable();
6135
6136         /* Unregister netfilter hooks. */
6137         selinux_nf_ip_exit();
6138
6139         /* Unregister selinuxfs. */
6140         exit_sel_fs();
6141
6142         return 0;
6143 }
6144 #endif