security/selinux/hooks.c

   1 /*
   2  *  NSA Security-Enhanced Linux (SELinux) security module
   3  *
   4  *  This file contains the SELinux hook function implementations.
   5  *
   6  *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
   7  *            Chris Vance, <cvance@nai.com>
   8  *            Wayne Salamon, <wsalamon@nai.com>
   9  *            James Morris <jmorris@redhat.com>
  10  *
  11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
  13  *                                         Eric Paris <eparis@redhat.com>
  14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  15  *                          <dgoeddel@trustedcs.com>
  16  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
  17  *      Paul Moore <paul@paul-moore.com>
  18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  19  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
  20  *
  21  *      This program is free software; you can redistribute it and/or modify
  22  *      it under the terms of the GNU General Public License version 2,
  23  *      as published by the Free Software Foundation.
  24  */
  25
  26 #include <linux/init.h>
  27 #include <linux/kd.h>
  28 #include <linux/kernel.h>
  29 #include <linux/tracehook.h>
  30 #include <linux/errno.h>
  31 #include <linux/ext2_fs.h>
  32 #include <linux/sched.h>
  33 #include <linux/security.h>
  34 #include <linux/xattr.h>
  35 #include <linux/capability.h>
  36 #include <linux/unistd.h>
  37 #include <linux/mm.h>
  38 #include <linux/mman.h>
  39 #include <linux/slab.h>
  40 #include <linux/pagemap.h>
  41 #include <linux/proc_fs.h>
  42 #include <linux/swap.h>
  43 #include <linux/spinlock.h>
  44 #include <linux/syscalls.h>
  45 #include <linux/dcache.h>
  46 #include <linux/file.h>
  47 #include <linux/fdtable.h>
  48 #include <linux/namei.h>
  49 #include <linux/mount.h>
  50 #include <linux/netfilter_ipv4.h>
  51 #include <linux/netfilter_ipv6.h>
  52 #include <linux/tty.h>
  53 #include <net/icmp.h>
  54 #include <net/ip.h>             /* for local_port_range[] */
  55 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  56 #include <net/net_namespace.h>
  57 #include <net/netlabel.h>
  58 #include <linux/uaccess.h>
  59 #include <asm/ioctls.h>
  60 #include <linux/atomic.h>
  61 #include <linux/bitops.h>
  62 #include <linux/interrupt.h>
  63 #include <linux/netdevice.h>    /* for network interface checks */
  64 #include <linux/netlink.h>
  65 #include <linux/tcp.h>
  66 #include <linux/udp.h>
  67 #include <linux/dccp.h>
  68 #include <linux/quota.h>
  69 #include <linux/un.h>           /* for Unix socket types */
  70 #include <net/af_unix.h>        /* for Unix socket types */
  71 #include <linux/parser.h>
  72 #include <linux/nfs_mount.h>
  73 #include <net/ipv6.h>
  74 #include <linux/hugetlb.h>
  75 #include <linux/personality.h>
  76 #include <linux/audit.h>
  77 #include <linux/string.h>
  78 #include <linux/selinux.h>
  79 #include <linux/mutex.h>
  80 #include <linux/posix-timers.h>
  81 #include <linux/syslog.h>
  82 #include <linux/user_namespace.h>
  83 #include <linux/export.h>
  84
  85 #include "avc.h"
  86 #include "objsec.h"
  87 #include "netif.h"
  88 #include "netnode.h"
  89 #include "netport.h"
  90 #include "xfrm.h"
  91 #include "netlabel.h"
  92 #include "audit.h"
  93 #include "avc_ss.h"
  94
  95 #define NUM_SEL_MNT_OPTS 5
  96
  97 extern struct security_operations *security_ops;
  98
  99 /* SECMARK reference count */
 100 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 101
 102 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 103 int selinux_enforcing;
 104
 105 static int __init enforcing_setup(char *str)
 106 {
 107         unsigned long enforcing;
 108         if (!strict_strtoul(str, 0, &enforcing))
 109                 selinux_enforcing = enforcing ? 1 : 0;
 110         return 1;
 111 }
 112 __setup("enforcing=", enforcing_setup);
 113 #endif
 114
 115 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 116 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
 117
 118 static int __init selinux_enabled_setup(char *str)
 119 {
 120         unsigned long enabled;
 121         if (!strict_strtoul(str, 0, &enabled))
 122                 selinux_enabled = enabled ? 1 : 0;
 123         return 1;
 124 }
 125 __setup("selinux=", selinux_enabled_setup);
 126 #else
 127 int selinux_enabled = 1;
 128 #endif
 129
 130 static struct kmem_cache *sel_inode_cache;
 131
 132 /**
 133  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 134  *
 135  * Description:
 136  * This function checks the SECMARK reference counter to see if any SECMARK
 137  * targets are currently configured, if the reference counter is greater than
 138  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 139  * enabled, false (0) if SECMARK is disabled.
 140  *
 141  */
 142 static int selinux_secmark_enabled(void)
 143 {
 144         return (atomic_read(&selinux_secmark_refcount) > 0);
 145 }
 146
 147 /*
 148  * initialise the security for the init task
 149  */
 150 static void cred_init_security(void)
 151 {
 152         struct cred *cred = (struct cred *) current->real_cred;
 153         struct task_security_struct *tsec;
 154
 155         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 156         if (!tsec)
 157                 panic("SELinux:  Failed to initialize initial task.\n");
 158
 159         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 160         cred->security = tsec;
 161 }
 162
 163 /*
 164  * get the security ID of a set of credentials
 165  */
 166 static inline u32 cred_sid(const struct cred *cred)
 167 {
 168         const struct task_security_struct *tsec;
 169
 170         tsec = cred->security;
 171         return tsec->sid;
 172 }
 173
 174 /*
 175  * get the objective security ID of a task
 176  */
 177 static inline u32 task_sid(const struct task_struct *task)
 178 {
 179         u32 sid;
 180
 181         rcu_read_lock();
 182         sid = cred_sid(__task_cred(task));
 183         rcu_read_unlock();
 184         return sid;
 185 }
 186
 187 /*
 188  * get the subjective security ID of the current task
 189  */
 190 static inline u32 current_sid(void)
 191 {
 192         const struct task_security_struct *tsec = current_security();
 193
 194         return tsec->sid;
 195 }
 196
 197 /* Allocate and free functions for each kind of security blob. */
 198
 199 static int inode_alloc_security(struct inode *inode)
 200 {
 201         struct inode_security_struct *isec;
 202         u32 sid = current_sid();
 203
 204         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
 205         if (!isec)
 206                 return -ENOMEM;
 207
 208         mutex_init(&isec->lock);
 209         INIT_LIST_HEAD(&isec->list);
 210         isec->inode = inode;
 211         isec->sid = SECINITSID_UNLABELED;
 212         isec->sclass = SECCLASS_FILE;
 213         isec->task_sid = sid;
 214         inode->i_security = isec;
 215
 216         return 0;
 217 }
 218
 219 static void inode_free_security(struct inode *inode)
 220 {
 221         struct inode_security_struct *isec = inode->i_security;
 222         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 223
 224         spin_lock(&sbsec->isec_lock);
 225         if (!list_empty(&isec->list))
 226                 list_del_init(&isec->list);
 227         spin_unlock(&sbsec->isec_lock);
 228
 229         inode->i_security = NULL;
 230         kmem_cache_free(sel_inode_cache, isec);
 231 }
 232
 233 static int file_alloc_security(struct file *file)
 234 {
 235         struct file_security_struct *fsec;
 236         u32 sid = current_sid();
 237
 238         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
 239         if (!fsec)
 240                 return -ENOMEM;
 241
 242         fsec->sid = sid;
 243         fsec->fown_sid = sid;
 244         file->f_security = fsec;
 245
 246         return 0;
 247 }
 248
 249 static void file_free_security(struct file *file)
 250 {
 251         struct file_security_struct *fsec = file->f_security;
 252         file->f_security = NULL;
 253         kfree(fsec);
 254 }
 255
 256 static int superblock_alloc_security(struct super_block *sb)
 257 {
 258         struct superblock_security_struct *sbsec;
 259
 260         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 261         if (!sbsec)
 262                 return -ENOMEM;
 263
 264         mutex_init(&sbsec->lock);
 265         INIT_LIST_HEAD(&sbsec->isec_head);
 266         spin_lock_init(&sbsec->isec_lock);
 267         sbsec->sb = sb;
 268         sbsec->sid = SECINITSID_UNLABELED;
 269         sbsec->def_sid = SECINITSID_FILE;
 270         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 271         sb->s_security = sbsec;
 272
 273         return 0;
 274 }
 275
 276 static void superblock_free_security(struct super_block *sb)
 277 {
 278         struct superblock_security_struct *sbsec = sb->s_security;
 279         sb->s_security = NULL;
 280         kfree(sbsec);
 281 }
 282
 283 /* The file system's label must be initialized prior to use. */
 284
 285 static const char *labeling_behaviors[6] = {
 286         "uses xattr",
 287         "uses transition SIDs",
 288         "uses task SIDs",
 289         "uses genfs_contexts",
 290         "not configured for labeling",
 291         "uses mountpoint labeling",
 292 };
 293
 294 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 295
 296 static inline int inode_doinit(struct inode *inode)
 297 {
 298         return inode_doinit_with_dentry(inode, NULL);
 299 }
 300
 301 enum {
 302         Opt_error = -1,
 303         Opt_context = 1,
 304         Opt_fscontext = 2,
 305         Opt_defcontext = 3,
 306         Opt_rootcontext = 4,
 307         Opt_labelsupport = 5,
 308 };
 309
 310 static const match_table_t tokens = {
 311         {Opt_context, CONTEXT_STR "%s"},
 312         {Opt_fscontext, FSCONTEXT_STR "%s"},
 313         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 314         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 315         {Opt_labelsupport, LABELSUPP_STR},
 316         {Opt_error, NULL},
 317 };
 318
 319 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 320
 321 static int may_context_mount_sb_relabel(u32 sid,
 322                         struct superblock_security_struct *sbsec,
 323                         const struct cred *cred)
 324 {
 325         const struct task_security_struct *tsec = cred->security;
 326         int rc;
 327
 328         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 329                           FILESYSTEM__RELABELFROM, NULL);
 330         if (rc)
 331                 return rc;
 332
 333         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 334                           FILESYSTEM__RELABELTO, NULL);
 335         return rc;
 336 }
 337
 338 static int may_context_mount_inode_relabel(u32 sid,
 339                         struct superblock_security_struct *sbsec,
 340                         const struct cred *cred)
 341 {
 342         const struct task_security_struct *tsec = cred->security;
 343         int rc;
 344         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 345                           FILESYSTEM__RELABELFROM, NULL);
 346         if (rc)
 347                 return rc;
 348
 349         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 350                           FILESYSTEM__ASSOCIATE, NULL);
 351         return rc;
 352 }
 353
 354 static int sb_finish_set_opts(struct super_block *sb)
 355 {
 356         struct superblock_security_struct *sbsec = sb->s_security;
 357         struct dentry *root = sb->s_root;
 358         struct inode *root_inode = root->d_inode;
 359         int rc = 0;
 360
 361         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 362                 /* Make sure that the xattr handler exists and that no
 363                    error other than -ENODATA is returned by getxattr on
 364                    the root directory.  -ENODATA is ok, as this may be
 365                    the first boot of the SELinux kernel before we have
 366                    assigned xattr values to the filesystem. */
 367                 if (!root_inode->i_op->getxattr) {
 368                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
 369                                "xattr support\n", sb->s_id, sb->s_type->name);
 370                         rc = -EOPNOTSUPP;
 371                         goto out;
 372                 }
 373                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
 374                 if (rc < 0 && rc != -ENODATA) {
 375                         if (rc == -EOPNOTSUPP)
 376                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 377                                        "%s) has no security xattr handler\n",
 378                                        sb->s_id, sb->s_type->name);
 379                         else
 380                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 381                                        "%s) getxattr errno %d\n", sb->s_id,
 382                                        sb->s_type->name, -rc);
 383                         goto out;
 384                 }
 385         }
 386
 387         sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
 388
 389         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 390                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
 391                        sb->s_id, sb->s_type->name);
 392         else
 393                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
 394                        sb->s_id, sb->s_type->name,
 395                        labeling_behaviors[sbsec->behavior-1]);
 396
 397         if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
 398             sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
 399             sbsec->behavior == SECURITY_FS_USE_NONE ||
 400             sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 401                 sbsec->flags &= ~SE_SBLABELSUPP;
 402
 403         /* Special handling for sysfs. Is genfs but also has setxattr handler*/
 404         if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
 405                 sbsec->flags |= SE_SBLABELSUPP;
 406
 407         /* Initialize the root inode. */
 408         rc = inode_doinit_with_dentry(root_inode, root);
 409
 410         /* Initialize any other inodes associated with the superblock, e.g.
 411            inodes created prior to initial policy load or inodes created
 412            during get_sb by a pseudo filesystem that directly
 413            populates itself. */
 414         spin_lock(&sbsec->isec_lock);
 415 next_inode:
 416         if (!list_empty(&sbsec->isec_head)) {
 417                 struct inode_security_struct *isec =
 418                                 list_entry(sbsec->isec_head.next,
 419                                            struct inode_security_struct, list);
 420                 struct inode *inode = isec->inode;
 421                 spin_unlock(&sbsec->isec_lock);
 422                 inode = igrab(inode);
 423                 if (inode) {
 424                         if (!IS_PRIVATE(inode))
 425                                 inode_doinit(inode);
 426                         iput(inode);
 427                 }
 428                 spin_lock(&sbsec->isec_lock);
 429                 list_del_init(&isec->list);
 430                 goto next_inode;
 431         }
 432         spin_unlock(&sbsec->isec_lock);
 433 out:
 434         return rc;
 435 }
 436
 437 /*
 438  * This function should allow an FS to ask what it's mount security
 439  * options were so it can use those later for submounts, displaying
 440  * mount options, or whatever.
 441  */
 442 static int selinux_get_mnt_opts(const struct super_block *sb,
 443                                 struct security_mnt_opts *opts)
 444 {
 445         int rc = 0, i;
 446         struct superblock_security_struct *sbsec = sb->s_security;
 447         char *context = NULL;
 448         u32 len;
 449         char tmp;
 450
 451         security_init_mnt_opts(opts);
 452
 453         if (!(sbsec->flags & SE_SBINITIALIZED))
 454                 return -EINVAL;
 455
 456         if (!ss_initialized)
 457                 return -EINVAL;
 458
 459         tmp = sbsec->flags & SE_MNTMASK;
 460         /* count the number of mount options for this sb */
 461         for (i = 0; i < 8; i++) {
 462                 if (tmp & 0x01)
 463                         opts->num_mnt_opts++;
 464                 tmp >>= 1;
 465         }
 466         /* Check if the Label support flag is set */
 467         if (sbsec->flags & SE_SBLABELSUPP)
 468                 opts->num_mnt_opts++;
 469
 470         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 471         if (!opts->mnt_opts) {
 472                 rc = -ENOMEM;
 473                 goto out_free;
 474         }
 475
 476         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 477         if (!opts->mnt_opts_flags) {
 478                 rc = -ENOMEM;
 479                 goto out_free;
 480         }
 481
 482         i = 0;
 483         if (sbsec->flags & FSCONTEXT_MNT) {
 484                 rc = security_sid_to_context(sbsec->sid, &context, &len);
 485                 if (rc)
 486                         goto out_free;
 487                 opts->mnt_opts[i] = context;
 488                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 489         }
 490         if (sbsec->flags & CONTEXT_MNT) {
 491                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
 492                 if (rc)
 493                         goto out_free;
 494                 opts->mnt_opts[i] = context;
 495                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 496         }
 497         if (sbsec->flags & DEFCONTEXT_MNT) {
 498                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
 499                 if (rc)
 500                         goto out_free;
 501                 opts->mnt_opts[i] = context;
 502                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 503         }
 504         if (sbsec->flags & ROOTCONTEXT_MNT) {
 505                 struct inode *root = sbsec->sb->s_root->d_inode;
 506                 struct inode_security_struct *isec = root->i_security;
 507
 508                 rc = security_sid_to_context(isec->sid, &context, &len);
 509                 if (rc)
 510                         goto out_free;
 511                 opts->mnt_opts[i] = context;
 512                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 513         }
 514         if (sbsec->flags & SE_SBLABELSUPP) {
 515                 opts->mnt_opts[i] = NULL;
 516                 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
 517         }
 518
 519         BUG_ON(i != opts->num_mnt_opts);
 520
 521         return 0;
 522
 523 out_free:
 524         security_free_mnt_opts(opts);
 525         return rc;
 526 }
 527
 528 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 529                       u32 old_sid, u32 new_sid)
 530 {
 531         char mnt_flags = sbsec->flags & SE_MNTMASK;
 532
 533         /* check if the old mount command had the same options */
 534         if (sbsec->flags & SE_SBINITIALIZED)
 535                 if (!(sbsec->flags & flag) ||
 536                     (old_sid != new_sid))
 537                         return 1;
 538
 539         /* check if we were passed the same options twice,
 540          * aka someone passed context=a,context=b
 541          */
 542         if (!(sbsec->flags & SE_SBINITIALIZED))
 543                 if (mnt_flags & flag)
 544                         return 1;
 545         return 0;
 546 }
 547
 548 /*
 549  * Allow filesystems with binary mount data to explicitly set mount point
 550  * labeling information.
 551  */
 552 static int selinux_set_mnt_opts(struct super_block *sb,
 553                                 struct security_mnt_opts *opts)
 554 {
 555         const struct cred *cred = current_cred();
 556         int rc = 0, i;
 557         struct superblock_security_struct *sbsec = sb->s_security;
 558         const char *name = sb->s_type->name;
 559         struct inode *inode = sbsec->sb->s_root->d_inode;
 560         struct inode_security_struct *root_isec = inode->i_security;
 561         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 562         u32 defcontext_sid = 0;
 563         char **mount_options = opts->mnt_opts;
 564         int *flags = opts->mnt_opts_flags;
 565         int num_opts = opts->num_mnt_opts;
 566
 567         mutex_lock(&sbsec->lock);
 568
 569         if (!ss_initialized) {
 570                 if (!num_opts) {
 571                         /* Defer initialization until selinux_complete_init,
 572                            after the initial policy is loaded and the security
 573                            server is ready to handle calls. */
 574                         goto out;
 575                 }
 576                 rc = -EINVAL;
 577                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
 578                         "before the security server is initialized\n");
 579                 goto out;
 580         }
 581
 582         /*
 583          * Binary mount data FS will come through this function twice.  Once
 584          * from an explicit call and once from the generic calls from the vfs.
 585          * Since the generic VFS calls will not contain any security mount data
 586          * we need to skip the double mount verification.
 587          *
 588          * This does open a hole in which we will not notice if the first
 589          * mount using this sb set explict options and a second mount using
 590          * this sb does not set any security options.  (The first options
 591          * will be used for both mounts)
 592          */
 593         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 594             && (num_opts == 0))
 595                 goto out;
 596
 597         /*
 598          * parse the mount options, check if they are valid sids.
 599          * also check if someone is trying to mount the same sb more
 600          * than once with different security options.
 601          */
 602         for (i = 0; i < num_opts; i++) {
 603                 u32 sid;
 604
 605                 if (flags[i] == SE_SBLABELSUPP)
 606                         continue;
 607                 rc = security_context_to_sid(mount_options[i],
 608                                              strlen(mount_options[i]), &sid);
 609                 if (rc) {
 610                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 611                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 612                                mount_options[i], sb->s_id, name, rc);
 613                         goto out;
 614                 }
 615                 switch (flags[i]) {
 616                 case FSCONTEXT_MNT:
 617                         fscontext_sid = sid;
 618
 619                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 620                                         fscontext_sid))
 621                                 goto out_double_mount;
 622
 623                         sbsec->flags |= FSCONTEXT_MNT;
 624                         break;
 625                 case CONTEXT_MNT:
 626                         context_sid = sid;
 627
 628                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 629                                         context_sid))
 630                                 goto out_double_mount;
 631
 632                         sbsec->flags |= CONTEXT_MNT;
 633                         break;
 634                 case ROOTCONTEXT_MNT:
 635                         rootcontext_sid = sid;
 636
 637                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 638                                         rootcontext_sid))
 639                                 goto out_double_mount;
 640
 641                         sbsec->flags |= ROOTCONTEXT_MNT;
 642
 643                         break;
 644                 case DEFCONTEXT_MNT:
 645                         defcontext_sid = sid;
 646
 647                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 648                                         defcontext_sid))
 649                                 goto out_double_mount;
 650
 651                         sbsec->flags |= DEFCONTEXT_MNT;
 652
 653                         break;
 654                 default:
 655                         rc = -EINVAL;
 656                         goto out;
 657                 }
 658         }
 659
 660         if (sbsec->flags & SE_SBINITIALIZED) {
 661                 /* previously mounted with options, but not on this attempt? */
 662                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
 663                         goto out_double_mount;
 664                 rc = 0;
 665                 goto out;
 666         }
 667
 668         if (strcmp(sb->s_type->name, "proc") == 0)
 669                 sbsec->flags |= SE_SBPROC;
 670
 671         /* Determine the labeling behavior to use for this filesystem type. */
 672         rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
 673         if (rc) {
 674                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
 675                        __func__, sb->s_type->name, rc);
 676                 goto out;
 677         }
 678
 679         /* sets the context of the superblock for the fs being mounted. */
 680         if (fscontext_sid) {
 681                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 682                 if (rc)
 683                         goto out;
 684
 685                 sbsec->sid = fscontext_sid;
 686         }
 687
 688         /*
 689          * Switch to using mount point labeling behavior.
 690          * sets the label used on all file below the mountpoint, and will set
 691          * the superblock context if not already set.
 692          */
 693         if (context_sid) {
 694                 if (!fscontext_sid) {
 695                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 696                                                           cred);
 697                         if (rc)
 698                                 goto out;
 699                         sbsec->sid = context_sid;
 700                 } else {
 701                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 702                                                              cred);
 703                         if (rc)
 704                                 goto out;
 705                 }
 706                 if (!rootcontext_sid)
 707                         rootcontext_sid = context_sid;
 708
 709                 sbsec->mntpoint_sid = context_sid;
 710                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 711         }
 712
 713         if (rootcontext_sid) {
 714                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 715                                                      cred);
 716                 if (rc)
 717                         goto out;
 718
 719                 root_isec->sid = rootcontext_sid;
 720                 root_isec->initialized = 1;
 721         }
 722
 723         if (defcontext_sid) {
 724                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
 725                         rc = -EINVAL;
 726                         printk(KERN_WARNING "SELinux: defcontext option is "
 727                                "invalid for this filesystem type\n");
 728                         goto out;
 729                 }
 730
 731                 if (defcontext_sid != sbsec->def_sid) {
 732                         rc = may_context_mount_inode_relabel(defcontext_sid,
 733                                                              sbsec, cred);
 734                         if (rc)
 735                                 goto out;
 736                 }
 737
 738                 sbsec->def_sid = defcontext_sid;
 739         }
 740
 741         rc = sb_finish_set_opts(sb);
 742 out:
 743         mutex_unlock(&sbsec->lock);
 744         return rc;
 745 out_double_mount:
 746         rc = -EINVAL;
 747         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 748                "security settings for (dev %s, type %s)\n", sb->s_id, name);
 749         goto out;
 750 }
 751
 752 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 753                                         struct super_block *newsb)
 754 {
 755         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 756         struct superblock_security_struct *newsbsec = newsb->s_security;
 757
 758         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 759         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 760         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 761
 762         /*
 763          * if the parent was able to be mounted it clearly had no special lsm
 764          * mount options.  thus we can safely deal with this superblock later
 765          */
 766         if (!ss_initialized)
 767                 return;
 768
 769         /* how can we clone if the old one wasn't set up?? */
 770         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 771
 772         /* if fs is reusing a sb, just let its options stand... */
 773         if (newsbsec->flags & SE_SBINITIALIZED)
 774                 return;
 775
 776         mutex_lock(&newsbsec->lock);
 777
 778         newsbsec->flags = oldsbsec->flags;
 779
 780         newsbsec->sid = oldsbsec->sid;
 781         newsbsec->def_sid = oldsbsec->def_sid;
 782         newsbsec->behavior = oldsbsec->behavior;
 783
 784         if (set_context) {
 785                 u32 sid = oldsbsec->mntpoint_sid;
 786
 787                 if (!set_fscontext)
 788                         newsbsec->sid = sid;
 789                 if (!set_rootcontext) {
 790                         struct inode *newinode = newsb->s_root->d_inode;
 791                         struct inode_security_struct *newisec = newinode->i_security;
 792                         newisec->sid = sid;
 793                 }
 794                 newsbsec->mntpoint_sid = sid;
 795         }
 796         if (set_rootcontext) {
 797                 const struct inode *oldinode = oldsb->s_root->d_inode;
 798                 const struct inode_security_struct *oldisec = oldinode->i_security;
 799                 struct inode *newinode = newsb->s_root->d_inode;
 800                 struct inode_security_struct *newisec = newinode->i_security;
 801
 802                 newisec->sid = oldisec->sid;
 803         }
 804
 805         sb_finish_set_opts(newsb);
 806         mutex_unlock(&newsbsec->lock);
 807 }
 808
 809 static int selinux_parse_opts_str(char *options,
 810                                   struct security_mnt_opts *opts)
 811 {
 812         char *p;
 813         char *context = NULL, *defcontext = NULL;
 814         char *fscontext = NULL, *rootcontext = NULL;
 815         int rc, num_mnt_opts = 0;
 816
 817         opts->num_mnt_opts = 0;
 818
 819         /* Standard string-based options. */
 820         while ((p = strsep(&options, "|")) != NULL) {
 821                 int token;
 822                 substring_t args[MAX_OPT_ARGS];
 823
 824                 if (!*p)
 825                         continue;
 826
 827                 token = match_token(p, tokens, args);
 828
 829                 switch (token) {
 830                 case Opt_context:
 831                         if (context || defcontext) {
 832                                 rc = -EINVAL;
 833                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 834                                 goto out_err;
 835                         }
 836                         context = match_strdup(&args[0]);
 837                         if (!context) {
 838                                 rc = -ENOMEM;
 839                                 goto out_err;
 840                         }
 841                         break;
 842
 843                 case Opt_fscontext:
 844                         if (fscontext) {
 845                                 rc = -EINVAL;
 846                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 847                                 goto out_err;
 848                         }
 849                         fscontext = match_strdup(&args[0]);
 850                         if (!fscontext) {
 851                                 rc = -ENOMEM;
 852                                 goto out_err;
 853                         }
 854                         break;
 855
 856                 case Opt_rootcontext:
 857                         if (rootcontext) {
 858                                 rc = -EINVAL;
 859                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 860                                 goto out_err;
 861                         }
 862                         rootcontext = match_strdup(&args[0]);
 863                         if (!rootcontext) {
 864                                 rc = -ENOMEM;
 865                                 goto out_err;
 866                         }
 867                         break;
 868
 869                 case Opt_defcontext:
 870                         if (context || defcontext) {
 871                                 rc = -EINVAL;
 872                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 873                                 goto out_err;
 874                         }
 875                         defcontext = match_strdup(&args[0]);
 876                         if (!defcontext) {
 877                                 rc = -ENOMEM;
 878                                 goto out_err;
 879                         }
 880                         break;
 881                 case Opt_labelsupport:
 882                         break;
 883                 default:
 884                         rc = -EINVAL;
 885                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
 886                         goto out_err;
 887
 888                 }
 889         }
 890
 891         rc = -ENOMEM;
 892         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
 893         if (!opts->mnt_opts)
 894                 goto out_err;
 895
 896         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
 897         if (!opts->mnt_opts_flags) {
 898                 kfree(opts->mnt_opts);
 899                 goto out_err;
 900         }
 901
 902         if (fscontext) {
 903                 opts->mnt_opts[num_mnt_opts] = fscontext;
 904                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
 905         }
 906         if (context) {
 907                 opts->mnt_opts[num_mnt_opts] = context;
 908                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
 909         }
 910         if (rootcontext) {
 911                 opts->mnt_opts[num_mnt_opts] = rootcontext;
 912                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
 913         }
 914         if (defcontext) {
 915                 opts->mnt_opts[num_mnt_opts] = defcontext;
 916                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
 917         }
 918
 919         opts->num_mnt_opts = num_mnt_opts;
 920         return 0;
 921
 922 out_err:
 923         kfree(context);
 924         kfree(defcontext);
 925         kfree(fscontext);
 926         kfree(rootcontext);
 927         return rc;
 928 }
 929 /*
 930  * string mount options parsing and call set the sbsec
 931  */
 932 static int superblock_doinit(struct super_block *sb, void *data)
 933 {
 934         int rc = 0;
 935         char *options = data;
 936         struct security_mnt_opts opts;
 937
 938         security_init_mnt_opts(&opts);
 939
 940         if (!data)
 941                 goto out;
 942
 943         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
 944
 945         rc = selinux_parse_opts_str(options, &opts);
 946         if (rc)
 947                 goto out_err;
 948
 949 out:
 950         rc = selinux_set_mnt_opts(sb, &opts);
 951
 952 out_err:
 953         security_free_mnt_opts(&opts);
 954         return rc;
 955 }
 956
 957 static void selinux_write_opts(struct seq_file *m,
 958                                struct security_mnt_opts *opts)
 959 {
 960         int i;
 961         char *prefix;
 962
 963         for (i = 0; i < opts->num_mnt_opts; i++) {
 964                 char *has_comma;
 965
 966                 if (opts->mnt_opts[i])
 967                         has_comma = strchr(opts->mnt_opts[i], ',');
 968                 else
 969                         has_comma = NULL;
 970
 971                 switch (opts->mnt_opts_flags[i]) {
 972                 case CONTEXT_MNT:
 973                         prefix = CONTEXT_STR;
 974                         break;
 975                 case FSCONTEXT_MNT:
 976                         prefix = FSCONTEXT_STR;
 977                         break;
 978                 case ROOTCONTEXT_MNT:
 979                         prefix = ROOTCONTEXT_STR;
 980                         break;
 981                 case DEFCONTEXT_MNT:
 982                         prefix = DEFCONTEXT_STR;
 983                         break;
 984                 case SE_SBLABELSUPP:
 985                         seq_putc(m, ',');
 986                         seq_puts(m, LABELSUPP_STR);
 987                         continue;
 988                 default:
 989                         BUG();
 990                         return;
 991                 };
 992                 /* we need a comma before each option */
 993                 seq_putc(m, ',');
 994                 seq_puts(m, prefix);
 995                 if (has_comma)
 996                         seq_putc(m, '\"');
 997                 seq_puts(m, opts->mnt_opts[i]);
 998                 if (has_comma)
 999                         seq_putc(m, '\"');
1000         }
1001 }
1002
1003 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1004 {
1005         struct security_mnt_opts opts;
1006         int rc;
1007
1008         rc = selinux_get_mnt_opts(sb, &opts);
1009         if (rc) {
1010                 /* before policy load we may get EINVAL, don't show anything */
1011                 if (rc == -EINVAL)
1012                         rc = 0;
1013                 return rc;
1014         }
1015
1016         selinux_write_opts(m, &opts);
1017
1018         security_free_mnt_opts(&opts);
1019
1020         return rc;
1021 }
1022
1023 static inline u16 inode_mode_to_security_class(umode_t mode)
1024 {
1025         switch (mode & S_IFMT) {
1026         case S_IFSOCK:
1027                 return SECCLASS_SOCK_FILE;
1028         case S_IFLNK:
1029                 return SECCLASS_LNK_FILE;
1030         case S_IFREG:
1031                 return SECCLASS_FILE;
1032         case S_IFBLK:
1033                 return SECCLASS_BLK_FILE;
1034         case S_IFDIR:
1035                 return SECCLASS_DIR;
1036         case S_IFCHR:
1037                 return SECCLASS_CHR_FILE;
1038         case S_IFIFO:
1039                 return SECCLASS_FIFO_FILE;
1040
1041         }
1042
1043         return SECCLASS_FILE;
1044 }
1045
1046 static inline int default_protocol_stream(int protocol)
1047 {
1048         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1049 }
1050
1051 static inline int default_protocol_dgram(int protocol)
1052 {
1053         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1054 }
1055
1056 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1057 {
1058         switch (family) {
1059         case PF_UNIX:
1060                 switch (type) {
1061                 case SOCK_STREAM:
1062                 case SOCK_SEQPACKET:
1063                         return SECCLASS_UNIX_STREAM_SOCKET;
1064                 case SOCK_DGRAM:
1065                         return SECCLASS_UNIX_DGRAM_SOCKET;
1066                 }
1067                 break;
1068         case PF_INET:
1069         case PF_INET6:
1070                 switch (type) {
1071                 case SOCK_STREAM:
1072                         if (default_protocol_stream(protocol))
1073                                 return SECCLASS_TCP_SOCKET;
1074                         else
1075                                 return SECCLASS_RAWIP_SOCKET;
1076                 case SOCK_DGRAM:
1077                         if (default_protocol_dgram(protocol))
1078                                 return SECCLASS_UDP_SOCKET;
1079                         else
1080                                 return SECCLASS_RAWIP_SOCKET;
1081                 case SOCK_DCCP:
1082                         return SECCLASS_DCCP_SOCKET;
1083                 default:
1084                         return SECCLASS_RAWIP_SOCKET;
1085                 }
1086                 break;
1087         case PF_NETLINK:
1088                 switch (protocol) {
1089                 case NETLINK_ROUTE:
1090                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1091                 case NETLINK_FIREWALL:
1092                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1093                 case NETLINK_INET_DIAG:
1094                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1095                 case NETLINK_NFLOG:
1096                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1097                 case NETLINK_XFRM:
1098                         return SECCLASS_NETLINK_XFRM_SOCKET;
1099                 case NETLINK_SELINUX:
1100                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1101                 case NETLINK_AUDIT:
1102                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1103                 case NETLINK_IP6_FW:
1104                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1105                 case NETLINK_DNRTMSG:
1106                         return SECCLASS_NETLINK_DNRT_SOCKET;
1107                 case NETLINK_KOBJECT_UEVENT:
1108                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1109                 default:
1110                         return SECCLASS_NETLINK_SOCKET;
1111                 }
1112         case PF_PACKET:
1113                 return SECCLASS_PACKET_SOCKET;
1114         case PF_KEY:
1115                 return SECCLASS_KEY_SOCKET;
1116         case PF_APPLETALK:
1117                 return SECCLASS_APPLETALK_SOCKET;
1118         }
1119
1120         return SECCLASS_SOCKET;
1121 }
1122
1123 #ifdef CONFIG_PROC_FS
1124 static int selinux_proc_get_sid(struct dentry *dentry,
1125                                 u16 tclass,
1126                                 u32 *sid)
1127 {
1128         int rc;
1129         char *buffer, *path;
1130
1131         buffer = (char *)__get_free_page(GFP_KERNEL);
1132         if (!buffer)
1133                 return -ENOMEM;
1134
1135         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1136         if (IS_ERR(path))
1137                 rc = PTR_ERR(path);
1138         else {
1139                 /* each process gets a /proc/PID/ entry. Strip off the
1140                  * PID part to get a valid selinux labeling.
1141                  * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1142                 while (path[1] >= '0' && path[1] <= '9') {
1143                         path[1] = '/';
1144                         path++;
1145                 }
1146                 rc = security_genfs_sid("proc", path, tclass, sid);
1147         }
1148         free_page((unsigned long)buffer);
1149         return rc;
1150 }
1151 #else
1152 static int selinux_proc_get_sid(struct dentry *dentry,
1153                                 u16 tclass,
1154                                 u32 *sid)
1155 {
1156         return -EINVAL;
1157 }
1158 #endif
1159
1160 /* The inode's security attributes must be initialized before first use. */
1161 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1162 {
1163         struct superblock_security_struct *sbsec = NULL;
1164         struct inode_security_struct *isec = inode->i_security;
1165         u32 sid;
1166         struct dentry *dentry;
1167 #define INITCONTEXTLEN 255
1168         char *context = NULL;
1169         unsigned len = 0;
1170         int rc = 0;
1171
1172         if (isec->initialized)
1173                 goto out;
1174
1175         mutex_lock(&isec->lock);
1176         if (isec->initialized)
1177                 goto out_unlock;
1178
1179         sbsec = inode->i_sb->s_security;
1180         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1181                 /* Defer initialization until selinux_complete_init,
1182                    after the initial policy is loaded and the security
1183                    server is ready to handle calls. */
1184                 spin_lock(&sbsec->isec_lock);
1185                 if (list_empty(&isec->list))
1186                         list_add(&isec->list, &sbsec->isec_head);
1187                 spin_unlock(&sbsec->isec_lock);
1188                 goto out_unlock;
1189         }
1190
1191         switch (sbsec->behavior) {
1192         case SECURITY_FS_USE_XATTR:
1193                 if (!inode->i_op->getxattr) {
1194                         isec->sid = sbsec->def_sid;
1195                         break;
1196                 }
1197
1198                 /* Need a dentry, since the xattr API requires one.
1199                    Life would be simpler if we could just pass the inode. */
1200                 if (opt_dentry) {
1201                         /* Called from d_instantiate or d_splice_alias. */
1202                         dentry = dget(opt_dentry);
1203                 } else {
1204                         /* Called from selinux_complete_init, try to find a dentry. */
1205                         dentry = d_find_alias(inode);
1206                 }
1207                 if (!dentry) {
1208                         /*
1209                          * this is can be hit on boot when a file is accessed
1210                          * before the policy is loaded.  When we load policy we
1211                          * may find inodes that have no dentry on the
1212                          * sbsec->isec_head list.  No reason to complain as these
1213                          * will get fixed up the next time we go through
1214                          * inode_doinit with a dentry, before these inodes could
1215                          * be used again by userspace.
1216                          */
1217                         goto out_unlock;
1218                 }
1219
1220                 len = INITCONTEXTLEN;
1221                 context = kmalloc(len+1, GFP_NOFS);
1222                 if (!context) {
1223                         rc = -ENOMEM;
1224                         dput(dentry);
1225                         goto out_unlock;
1226                 }
1227                 context[len] = '\0';
1228                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1229                                            context, len);
1230                 if (rc == -ERANGE) {
1231                         kfree(context);
1232
1233                         /* Need a larger buffer.  Query for the right size. */
1234                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1235                                                    NULL, 0);
1236                         if (rc < 0) {
1237                                 dput(dentry);
1238                                 goto out_unlock;
1239                         }
1240                         len = rc;
1241                         context = kmalloc(len+1, GFP_NOFS);
1242                         if (!context) {
1243                                 rc = -ENOMEM;
1244                                 dput(dentry);
1245                                 goto out_unlock;
1246                         }
1247                         context[len] = '\0';
1248                         rc = inode->i_op->getxattr(dentry,
1249                                                    XATTR_NAME_SELINUX,
1250                                                    context, len);
1251                 }
1252                 dput(dentry);
1253                 if (rc < 0) {
1254                         if (rc != -ENODATA) {
1255                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1256                                        "%d for dev=%s ino=%ld\n", __func__,
1257                                        -rc, inode->i_sb->s_id, inode->i_ino);
1258                                 kfree(context);
1259                                 goto out_unlock;
1260                         }
1261                         /* Map ENODATA to the default file SID */
1262                         sid = sbsec->def_sid;
1263                         rc = 0;
1264                 } else {
1265                         rc = security_context_to_sid_default(context, rc, &sid,
1266                                                              sbsec->def_sid,
1267                                                              GFP_NOFS);
1268                         if (rc) {
1269                                 char *dev = inode->i_sb->s_id;
1270                                 unsigned long ino = inode->i_ino;
1271
1272                                 if (rc == -EINVAL) {
1273                                         if (printk_ratelimit())
1274                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1275                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1276                                                         "filesystem in question.\n", ino, dev, context);
1277                                 } else {
1278                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1279                                                "returned %d for dev=%s ino=%ld\n",
1280                                                __func__, context, -rc, dev, ino);
1281                                 }
1282                                 kfree(context);
1283                                 /* Leave with the unlabeled SID */
1284                                 rc = 0;
1285                                 break;
1286                         }
1287                 }
1288                 kfree(context);
1289                 isec->sid = sid;
1290                 break;
1291         case SECURITY_FS_USE_TASK:
1292                 isec->sid = isec->task_sid;
1293                 break;
1294         case SECURITY_FS_USE_TRANS:
1295                 /* Default to the fs SID. */
1296                 isec->sid = sbsec->sid;
1297
1298                 /* Try to obtain a transition SID. */
1299                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1300                 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1301                                              isec->sclass, NULL, &sid);
1302                 if (rc)
1303                         goto out_unlock;
1304                 isec->sid = sid;
1305                 break;
1306         case SECURITY_FS_USE_MNTPOINT:
1307                 isec->sid = sbsec->mntpoint_sid;
1308                 break;
1309         default:
1310                 /* Default to the fs superblock SID. */
1311                 isec->sid = sbsec->sid;
1312
1313                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1314                         if (opt_dentry) {
1315                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1316                                 rc = selinux_proc_get_sid(opt_dentry,
1317                                                           isec->sclass,
1318                                                           &sid);
1319                                 if (rc)
1320                                         goto out_unlock;
1321                                 isec->sid = sid;
1322                         }
1323                 }
1324                 break;
1325         }
1326
1327         isec->initialized = 1;
1328
1329 out_unlock:
1330         mutex_unlock(&isec->lock);
1331 out:
1332         if (isec->sclass == SECCLASS_FILE)
1333                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1334         return rc;
1335 }
1336
1337 /* Convert a Linux signal to an access vector. */
1338 static inline u32 signal_to_av(int sig)
1339 {
1340         u32 perm = 0;
1341
1342         switch (sig) {
1343         case SIGCHLD:
1344                 /* Commonly granted from child to parent. */
1345                 perm = PROCESS__SIGCHLD;
1346                 break;
1347         case SIGKILL:
1348                 /* Cannot be caught or ignored */
1349                 perm = PROCESS__SIGKILL;
1350                 break;
1351         case SIGSTOP:
1352                 /* Cannot be caught or ignored */
1353                 perm = PROCESS__SIGSTOP;
1354                 break;
1355         default:
1356                 /* All other signals. */
1357                 perm = PROCESS__SIGNAL;
1358                 break;
1359         }
1360
1361         return perm;
1362 }
1363
1364 /*
1365  * Check permission between a pair of credentials
1366  * fork check, ptrace check, etc.
1367  */
1368 static int cred_has_perm(const struct cred *actor,
1369                          const struct cred *target,
1370                          u32 perms)
1371 {
1372         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1373
1374         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1375 }
1376
1377 /*
1378  * Check permission between a pair of tasks, e.g. signal checks,
1379  * fork check, ptrace check, etc.
1380  * tsk1 is the actor and tsk2 is the target
1381  * - this uses the default subjective creds of tsk1
1382  */
1383 static int task_has_perm(const struct task_struct *tsk1,
1384                          const struct task_struct *tsk2,
1385                          u32 perms)
1386 {
1387         const struct task_security_struct *__tsec1, *__tsec2;
1388         u32 sid1, sid2;
1389
1390         rcu_read_lock();
1391         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1392         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1393         rcu_read_unlock();
1394         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1395 }
1396
1397 /*
1398  * Check permission between current and another task, e.g. signal checks,
1399  * fork check, ptrace check, etc.
1400  * current is the actor and tsk2 is the target
1401  * - this uses current's subjective creds
1402  */
1403 static int current_has_perm(const struct task_struct *tsk,
1404                             u32 perms)
1405 {
1406         u32 sid, tsid;
1407
1408         sid = current_sid();
1409         tsid = task_sid(tsk);
1410         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1411 }
1412
1413 #if CAP_LAST_CAP > 63
1414 #error Fix SELinux to handle capabilities > 63.
1415 #endif
1416
1417 /* Check whether a task is allowed to use a capability. */
1418 static int task_has_capability(struct task_struct *tsk,
1419                                const struct cred *cred,
1420                                int cap, int audit)
1421 {
1422         struct common_audit_data ad;
1423         struct av_decision avd;
1424         u16 sclass;
1425         u32 sid = cred_sid(cred);
1426         u32 av = CAP_TO_MASK(cap);
1427         int rc;
1428
1429         COMMON_AUDIT_DATA_INIT(&ad, CAP);
1430         ad.tsk = tsk;
1431         ad.u.cap = cap;
1432
1433         switch (CAP_TO_INDEX(cap)) {
1434         case 0:
1435                 sclass = SECCLASS_CAPABILITY;
1436                 break;
1437         case 1:
1438                 sclass = SECCLASS_CAPABILITY2;
1439                 break;
1440         default:
1441                 printk(KERN_ERR
1442                        "SELinux:  out of range capability %d\n", cap);
1443                 BUG();
1444                 return -EINVAL;
1445         }
1446
1447         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1448         if (audit == SECURITY_CAP_AUDIT) {
1449                 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1450                 if (rc2)
1451                         return rc2;
1452         }
1453         return rc;
1454 }
1455
1456 /* Check whether a task is allowed to use a system operation. */
1457 static int task_has_system(struct task_struct *tsk,
1458                            u32 perms)
1459 {
1460         u32 sid = task_sid(tsk);
1461
1462         return avc_has_perm(sid, SECINITSID_KERNEL,
1463                             SECCLASS_SYSTEM, perms, NULL);
1464 }
1465
1466 /* Check whether a task has a particular permission to an inode.
1467    The 'adp' parameter is optional and allows other audit
1468    data to be passed (e.g. the dentry). */
1469 static int inode_has_perm(const struct cred *cred,
1470                           struct inode *inode,
1471                           u32 perms,
1472                           struct common_audit_data *adp,
1473                           unsigned flags)
1474 {
1475         struct inode_security_struct *isec;
1476         u32 sid;
1477
1478         validate_creds(cred);
1479
1480         if (unlikely(IS_PRIVATE(inode)))
1481                 return 0;
1482
1483         sid = cred_sid(cred);
1484         isec = inode->i_security;
1485
1486         return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1487 }
1488
1489 static int inode_has_perm_noadp(const struct cred *cred,
1490                                 struct inode *inode,
1491                                 u32 perms,
1492                                 unsigned flags)
1493 {
1494         struct common_audit_data ad;
1495
1496         COMMON_AUDIT_DATA_INIT(&ad, INODE);
1497         ad.u.inode = inode;
1498         return inode_has_perm(cred, inode, perms, &ad, flags);
1499 }
1500
1501 /* Same as inode_has_perm, but pass explicit audit data containing
1502    the dentry to help the auditing code to more easily generate the
1503    pathname if needed. */
1504 static inline int dentry_has_perm(const struct cred *cred,
1505                                   struct dentry *dentry,
1506                                   u32 av)
1507 {
1508         struct inode *inode = dentry->d_inode;
1509         struct common_audit_data ad;
1510
1511         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1512         ad.u.dentry = dentry;
1513         return inode_has_perm(cred, inode, av, &ad, 0);
1514 }
1515
1516 /* Same as inode_has_perm, but pass explicit audit data containing
1517    the path to help the auditing code to more easily generate the
1518    pathname if needed. */
1519 static inline int path_has_perm(const struct cred *cred,
1520                                 struct path *path,
1521                                 u32 av)
1522 {
1523         struct inode *inode = path->dentry->d_inode;
1524         struct common_audit_data ad;
1525
1526         COMMON_AUDIT_DATA_INIT(&ad, PATH);
1527         ad.u.path = *path;
1528         return inode_has_perm(cred, inode, av, &ad, 0);
1529 }
1530
1531 /* Check whether a task can use an open file descriptor to
1532    access an inode in a given way.  Check access to the
1533    descriptor itself, and then use dentry_has_perm to
1534    check a particular permission to the file.
1535    Access to the descriptor is implicitly granted if it
1536    has the same SID as the process.  If av is zero, then
1537    access to the file is not checked, e.g. for cases
1538    where only the descriptor is affected like seek. */
1539 static int file_has_perm(const struct cred *cred,
1540                          struct file *file,
1541                          u32 av)
1542 {
1543         struct file_security_struct *fsec = file->f_security;
1544         struct inode *inode = file->f_path.dentry->d_inode;
1545         struct common_audit_data ad;
1546         u32 sid = cred_sid(cred);
1547         int rc;
1548
1549         COMMON_AUDIT_DATA_INIT(&ad, PATH);
1550         ad.u.path = file->f_path;
1551
1552         if (sid != fsec->sid) {
1553                 rc = avc_has_perm(sid, fsec->sid,
1554                                   SECCLASS_FD,
1555                                   FD__USE,
1556                                   &ad);
1557                 if (rc)
1558                         goto out;
1559         }
1560
1561         /* av is zero if only checking access to the descriptor. */
1562         rc = 0;
1563         if (av)
1564                 rc = inode_has_perm(cred, inode, av, &ad, 0);
1565
1566 out:
1567         return rc;
1568 }
1569
1570 /* Check whether a task can create a file. */
1571 static int may_create(struct inode *dir,
1572                       struct dentry *dentry,
1573                       u16 tclass)
1574 {
1575         const struct task_security_struct *tsec = current_security();
1576         struct inode_security_struct *dsec;
1577         struct superblock_security_struct *sbsec;
1578         u32 sid, newsid;
1579         struct common_audit_data ad;
1580         int rc;
1581
1582         dsec = dir->i_security;
1583         sbsec = dir->i_sb->s_security;
1584
1585         sid = tsec->sid;
1586         newsid = tsec->create_sid;
1587
1588         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1589         ad.u.dentry = dentry;
1590
1591         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1592                           DIR__ADD_NAME | DIR__SEARCH,
1593                           &ad);
1594         if (rc)
1595                 return rc;
1596
1597         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1598                 rc = security_transition_sid(sid, dsec->sid, tclass,
1599                                              &dentry->d_name, &newsid);
1600                 if (rc)
1601                         return rc;
1602         }
1603
1604         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1605         if (rc)
1606                 return rc;
1607
1608         return avc_has_perm(newsid, sbsec->sid,
1609                             SECCLASS_FILESYSTEM,
1610                             FILESYSTEM__ASSOCIATE, &ad);
1611 }
1612
1613 /* Check whether a task can create a key. */
1614 static int may_create_key(u32 ksid,
1615                           struct task_struct *ctx)
1616 {
1617         u32 sid = task_sid(ctx);
1618
1619         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1620 }
1621
1622 #define MAY_LINK        0
1623 #define MAY_UNLINK      1
1624 #define MAY_RMDIR       2
1625
1626 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1627 static int may_link(struct inode *dir,
1628                     struct dentry *dentry,
1629                     int kind)
1630
1631 {
1632         struct inode_security_struct *dsec, *isec;
1633         struct common_audit_data ad;
1634         u32 sid = current_sid();
1635         u32 av;
1636         int rc;
1637
1638         dsec = dir->i_security;
1639         isec = dentry->d_inode->i_security;
1640
1641         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1642         ad.u.dentry = dentry;
1643
1644         av = DIR__SEARCH;
1645         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1646         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1647         if (rc)
1648                 return rc;
1649
1650         switch (kind) {
1651         case MAY_LINK:
1652                 av = FILE__LINK;
1653                 break;
1654         case MAY_UNLINK:
1655                 av = FILE__UNLINK;
1656                 break;
1657         case MAY_RMDIR:
1658                 av = DIR__RMDIR;
1659                 break;
1660         default:
1661                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1662                         __func__, kind);
1663                 return 0;
1664         }
1665
1666         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1667         return rc;
1668 }
1669
1670 static inline int may_rename(struct inode *old_dir,
1671                              struct dentry *old_dentry,
1672                              struct inode *new_dir,
1673                              struct dentry *new_dentry)
1674 {
1675         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1676         struct common_audit_data ad;
1677         u32 sid = current_sid();
1678         u32 av;
1679         int old_is_dir, new_is_dir;
1680         int rc;
1681
1682         old_dsec = old_dir->i_security;
1683         old_isec = old_dentry->d_inode->i_security;
1684         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1685         new_dsec = new_dir->i_security;
1686
1687         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1688
1689         ad.u.dentry = old_dentry;
1690         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1691                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1692         if (rc)
1693                 return rc;
1694         rc = avc_has_perm(sid, old_isec->sid,
1695                           old_isec->sclass, FILE__RENAME, &ad);
1696         if (rc)
1697                 return rc;
1698         if (old_is_dir && new_dir != old_dir) {
1699                 rc = avc_has_perm(sid, old_isec->sid,
1700                                   old_isec->sclass, DIR__REPARENT, &ad);
1701                 if (rc)
1702                         return rc;
1703         }
1704
1705         ad.u.dentry = new_dentry;
1706         av = DIR__ADD_NAME | DIR__SEARCH;
1707         if (new_dentry->d_inode)
1708                 av |= DIR__REMOVE_NAME;
1709         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1710         if (rc)
1711                 return rc;
1712         if (new_dentry->d_inode) {
1713                 new_isec = new_dentry->d_inode->i_security;
1714                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1715                 rc = avc_has_perm(sid, new_isec->sid,
1716                                   new_isec->sclass,
1717                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1718                 if (rc)
1719                         return rc;
1720         }
1721
1722         return 0;
1723 }
1724
1725 /* Check whether a task can perform a filesystem operation. */
1726 static int superblock_has_perm(const struct cred *cred,
1727                                struct super_block *sb,
1728                                u32 perms,
1729                                struct common_audit_data *ad)
1730 {
1731         struct superblock_security_struct *sbsec;
1732         u32 sid = cred_sid(cred);
1733
1734         sbsec = sb->s_security;
1735         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1736 }
1737
1738 /* Convert a Linux mode and permission mask to an access vector. */
1739 static inline u32 file_mask_to_av(int mode, int mask)
1740 {
1741         u32 av = 0;
1742
1743         if ((mode & S_IFMT) != S_IFDIR) {
1744                 if (mask & MAY_EXEC)
1745                         av |= FILE__EXECUTE;
1746                 if (mask & MAY_READ)
1747                         av |= FILE__READ;
1748
1749                 if (mask & MAY_APPEND)
1750                         av |= FILE__APPEND;
1751                 else if (mask & MAY_WRITE)
1752                         av |= FILE__WRITE;
1753
1754         } else {
1755                 if (mask & MAY_EXEC)
1756                         av |= DIR__SEARCH;
1757                 if (mask & MAY_WRITE)
1758                         av |= DIR__WRITE;
1759                 if (mask & MAY_READ)
1760                         av |= DIR__READ;
1761         }
1762
1763         return av;
1764 }
1765
1766 /* Convert a Linux file to an access vector. */
1767 static inline u32 file_to_av(struct file *file)
1768 {
1769         u32 av = 0;
1770
1771         if (file->f_mode & FMODE_READ)
1772                 av |= FILE__READ;
1773         if (file->f_mode & FMODE_WRITE) {
1774                 if (file->f_flags & O_APPEND)
1775                         av |= FILE__APPEND;
1776                 else
1777                         av |= FILE__WRITE;
1778         }
1779         if (!av) {
1780                 /*
1781                  * Special file opened with flags 3 for ioctl-only use.
1782                  */
1783                 av = FILE__IOCTL;
1784         }
1785
1786         return av;
1787 }
1788
1789 /*
1790  * Convert a file to an access vector and include the correct open
1791  * open permission.
1792  */
1793 static inline u32 open_file_to_av(struct file *file)
1794 {
1795         u32 av = file_to_av(file);
1796
1797         if (selinux_policycap_openperm)
1798                 av |= FILE__OPEN;
1799
1800         return av;
1801 }
1802
1803 /* Hook functions begin here. */
1804
1805 static int selinux_ptrace_access_check(struct task_struct *child,
1806                                      unsigned int mode)
1807 {
1808         int rc;
1809
1810         rc = cap_ptrace_access_check(child, mode);
1811         if (rc)
1812                 return rc;
1813
1814         if (mode == PTRACE_MODE_READ) {
1815                 u32 sid = current_sid();
1816                 u32 csid = task_sid(child);
1817                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1818         }
1819
1820         return current_has_perm(child, PROCESS__PTRACE);
1821 }
1822
1823 static int selinux_ptrace_traceme(struct task_struct *parent)
1824 {
1825         int rc;
1826
1827         rc = cap_ptrace_traceme(parent);
1828         if (rc)
1829                 return rc;
1830
1831         return task_has_perm(parent, current, PROCESS__PTRACE);
1832 }
1833
1834 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1835                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1836 {
1837         int error;
1838
1839         error = current_has_perm(target, PROCESS__GETCAP);
1840         if (error)
1841                 return error;
1842
1843         return cap_capget(target, effective, inheritable, permitted);
1844 }
1845
1846 static int selinux_capset(struct cred *new, const struct cred *old,
1847                           const kernel_cap_t *effective,
1848                           const kernel_cap_t *inheritable,
1849                           const kernel_cap_t *permitted)
1850 {
1851         int error;
1852
1853         error = cap_capset(new, old,
1854                                       effective, inheritable, permitted);
1855         if (error)
1856                 return error;
1857
1858         return cred_has_perm(old, new, PROCESS__SETCAP);
1859 }
1860
1861 /*
1862  * (This comment used to live with the selinux_task_setuid hook,
1863  * which was removed).
1864  *
1865  * Since setuid only affects the current process, and since the SELinux
1866  * controls are not based on the Linux identity attributes, SELinux does not
1867  * need to control this operation.  However, SELinux does control the use of
1868  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1869  */
1870
1871 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1872                            struct user_namespace *ns, int cap, int audit)
1873 {
1874         int rc;
1875
1876         rc = cap_capable(tsk, cred, ns, cap, audit);
1877         if (rc)
1878                 return rc;
1879
1880         return task_has_capability(tsk, cred, cap, audit);
1881 }
1882
1883 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1884 {
1885         const struct cred *cred = current_cred();
1886         int rc = 0;
1887
1888         if (!sb)
1889                 return 0;
1890
1891         switch (cmds) {
1892         case Q_SYNC:
1893         case Q_QUOTAON:
1894         case Q_QUOTAOFF:
1895         case Q_SETINFO:
1896         case Q_SETQUOTA:
1897                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1898                 break;
1899         case Q_GETFMT:
1900         case Q_GETINFO:
1901         case Q_GETQUOTA:
1902                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1903                 break;
1904         default:
1905                 rc = 0;  /* let the kernel handle invalid cmds */
1906                 break;
1907         }
1908         return rc;
1909 }
1910
1911 static int selinux_quota_on(struct dentry *dentry)
1912 {
1913         const struct cred *cred = current_cred();
1914
1915         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
1916 }
1917
1918 static int selinux_syslog(int type)
1919 {
1920         int rc;
1921
1922         switch (type) {
1923         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
1924         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1925                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1926                 break;
1927         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1928         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
1929         /* Set level of messages printed to console */
1930         case SYSLOG_ACTION_CONSOLE_LEVEL:
1931                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1932                 break;
1933         case SYSLOG_ACTION_CLOSE:       /* Close log */
1934         case SYSLOG_ACTION_OPEN:        /* Open log */
1935         case SYSLOG_ACTION_READ:        /* Read from log */
1936         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
1937         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
1938         default:
1939                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1940                 break;
1941         }
1942         return rc;
1943 }
1944
1945 /*
1946  * Check that a process has enough memory to allocate a new virtual
1947  * mapping. 0 means there is enough memory for the allocation to
1948  * succeed and -ENOMEM implies there is not.
1949  *
1950  * Do not audit the selinux permission check, as this is applied to all
1951  * processes that allocate mappings.
1952  */
1953 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1954 {
1955         int rc, cap_sys_admin = 0;
1956
1957         rc = selinux_capable(current, current_cred(),
1958                              &init_user_ns, CAP_SYS_ADMIN,
1959                              SECURITY_CAP_NOAUDIT);
1960         if (rc == 0)
1961                 cap_sys_admin = 1;
1962
1963         return __vm_enough_memory(mm, pages, cap_sys_admin);
1964 }
1965
1966 /* binprm security operations */
1967
1968 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
1969 {
1970         const struct task_security_struct *old_tsec;
1971         struct task_security_struct *new_tsec;
1972         struct inode_security_struct *isec;
1973         struct common_audit_data ad;
1974         struct inode *inode = bprm->file->f_path.dentry->d_inode;
1975         int rc;
1976
1977         rc = cap_bprm_set_creds(bprm);
1978         if (rc)
1979                 return rc;
1980
1981         /* SELinux context only depends on initial program or script and not
1982          * the script interpreter */
1983         if (bprm->cred_prepared)
1984                 return 0;
1985
1986         old_tsec = current_security();
1987         new_tsec = bprm->cred->security;
1988         isec = inode->i_security;
1989
1990         /* Default to the current task SID. */
1991         new_tsec->sid = old_tsec->sid;
1992         new_tsec->osid = old_tsec->sid;
1993
1994         /* Reset fs, key, and sock SIDs on execve. */
1995         new_tsec->create_sid = 0;
1996         new_tsec->keycreate_sid = 0;
1997         new_tsec->sockcreate_sid = 0;
1998
1999         if (old_tsec->exec_sid) {
2000                 new_tsec->sid = old_tsec->exec_sid;
2001                 /* Reset exec SID on execve. */
2002                 new_tsec->exec_sid = 0;
2003         } else {
2004                 /* Check for a default transition on this program. */
2005                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2006                                              SECCLASS_PROCESS, NULL,
2007                                              &new_tsec->sid);
2008                 if (rc)
2009                         return rc;
2010         }
2011
2012         COMMON_AUDIT_DATA_INIT(&ad, PATH);
2013         ad.u.path = bprm->file->f_path;
2014
2015         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2016                 new_tsec->sid = old_tsec->sid;
2017
2018         if (new_tsec->sid == old_tsec->sid) {
2019                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2020                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2021                 if (rc)
2022                         return rc;
2023         } else {
2024                 /* Check permissions for the transition. */
2025                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2026                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2027                 if (rc)
2028                         return rc;
2029
2030                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2031                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2032                 if (rc)
2033                         return rc;
2034
2035                 /* Check for shared state */
2036                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2037                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2038                                           SECCLASS_PROCESS, PROCESS__SHARE,
2039                                           NULL);
2040                         if (rc)
2041                                 return -EPERM;
2042                 }
2043
2044                 /* Make sure that anyone attempting to ptrace over a task that
2045                  * changes its SID has the appropriate permit */
2046                 if (bprm->unsafe &
2047                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2048                         struct task_struct *tracer;
2049                         struct task_security_struct *sec;
2050                         u32 ptsid = 0;
2051
2052                         rcu_read_lock();
2053                         tracer = ptrace_parent(current);
2054                         if (likely(tracer != NULL)) {
2055                                 sec = __task_cred(tracer)->security;
2056                                 ptsid = sec->sid;
2057                         }
2058                         rcu_read_unlock();
2059
2060                         if (ptsid != 0) {
2061                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2062                                                   SECCLASS_PROCESS,
2063                                                   PROCESS__PTRACE, NULL);
2064                                 if (rc)
2065                                         return -EPERM;
2066                         }
2067                 }
2068
2069                 /* Clear any possibly unsafe personality bits on exec: */
2070                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2071         }
2072
2073         return 0;
2074 }
2075
2076 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2077 {
2078         const struct task_security_struct *tsec = current_security();
2079         u32 sid, osid;
2080         int atsecure = 0;
2081
2082         sid = tsec->sid;
2083         osid = tsec->osid;
2084
2085         if (osid != sid) {
2086                 /* Enable secure mode for SIDs transitions unless
2087                    the noatsecure permission is granted between
2088                    the two SIDs, i.e. ahp returns 0. */
2089                 atsecure = avc_has_perm(osid, sid,
2090                                         SECCLASS_PROCESS,
2091                                         PROCESS__NOATSECURE, NULL);
2092         }
2093
2094         return (atsecure || cap_bprm_secureexec(bprm));
2095 }
2096
2097 /* Derived from fs/exec.c:flush_old_files. */
2098 static inline void flush_unauthorized_files(const struct cred *cred,
2099                                             struct files_struct *files)
2100 {
2101         struct common_audit_data ad;
2102         struct file *file, *devnull = NULL;
2103         struct tty_struct *tty;
2104         struct fdtable *fdt;
2105         long j = -1;
2106         int drop_tty = 0;
2107
2108         tty = get_current_tty();
2109         if (tty) {
2110                 spin_lock(&tty_files_lock);
2111                 if (!list_empty(&tty->tty_files)) {
2112                         struct tty_file_private *file_priv;
2113                         struct inode *inode;
2114
2115                         /* Revalidate access to controlling tty.
2116                            Use inode_has_perm on the tty inode directly rather
2117                            than using file_has_perm, as this particular open
2118                            file may belong to another process and we are only
2119                            interested in the inode-based check here. */
2120                         file_priv = list_first_entry(&tty->tty_files,
2121                                                 struct tty_file_private, list);
2122                         file = file_priv->file;
2123                         inode = file->f_path.dentry->d_inode;
2124                         if (inode_has_perm_noadp(cred, inode,
2125                                            FILE__READ | FILE__WRITE, 0)) {
2126                                 drop_tty = 1;
2127                         }
2128                 }
2129                 spin_unlock(&tty_files_lock);
2130                 tty_kref_put(tty);
2131         }
2132         /* Reset controlling tty. */
2133         if (drop_tty)
2134                 no_tty();
2135
2136         /* Revalidate access to inherited open files. */
2137
2138         COMMON_AUDIT_DATA_INIT(&ad, INODE);
2139
2140         spin_lock(&files->file_lock);
2141         for (;;) {
2142                 unsigned long set, i;
2143                 int fd;
2144
2145                 j++;
2146                 i = j * __NFDBITS;
2147                 fdt = files_fdtable(files);
2148                 if (i >= fdt->max_fds)
2149                         break;
2150                 set = fdt->open_fds->fds_bits[j];
2151                 if (!set)
2152                         continue;
2153                 spin_unlock(&files->file_lock);
2154                 for ( ; set ; i++, set >>= 1) {
2155                         if (set & 1) {
2156                                 file = fget(i);
2157                                 if (!file)
2158                                         continue;
2159                                 if (file_has_perm(cred,
2160                                                   file,
2161                                                   file_to_av(file))) {
2162                                         sys_close(i);
2163                                         fd = get_unused_fd();
2164                                         if (fd != i) {
2165                                                 if (fd >= 0)
2166                                                         put_unused_fd(fd);
2167                                                 fput(file);
2168                                                 continue;
2169                                         }
2170                                         if (devnull) {
2171                                                 get_file(devnull);
2172                                         } else {
2173                                                 devnull = dentry_open(
2174                                                         dget(selinux_null),
2175                                                         mntget(selinuxfs_mount),
2176                                                         O_RDWR, cred);
2177                                                 if (IS_ERR(devnull)) {
2178                                                         devnull = NULL;
2179                                                         put_unused_fd(fd);
2180                                                         fput(file);
2181                                                         continue;
2182                                                 }
2183                                         }
2184                                         fd_install(fd, devnull);
2185                                 }
2186                                 fput(file);
2187                         }
2188                 }
2189                 spin_lock(&files->file_lock);
2190
2191         }
2192         spin_unlock(&files->file_lock);
2193 }
2194
2195 /*
2196  * Prepare a process for imminent new credential changes due to exec
2197  */
2198 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2199 {
2200         struct task_security_struct *new_tsec;
2201         struct rlimit *rlim, *initrlim;
2202         int rc, i;
2203
2204         new_tsec = bprm->cred->security;
2205         if (new_tsec->sid == new_tsec->osid)
2206                 return;
2207
2208         /* Close files for which the new task SID is not authorized. */
2209         flush_unauthorized_files(bprm->cred, current->files);
2210
2211         /* Always clear parent death signal on SID transitions. */
2212         current->pdeath_signal = 0;
2213
2214         /* Check whether the new SID can inherit resource limits from the old
2215          * SID.  If not, reset all soft limits to the lower of the current
2216          * task's hard limit and the init task's soft limit.
2217          *
2218          * Note that the setting of hard limits (even to lower them) can be
2219          * controlled by the setrlimit check.  The inclusion of the init task's
2220          * soft limit into the computation is to avoid resetting soft limits
2221          * higher than the default soft limit for cases where the default is
2222          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2223          */
2224         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2225                           PROCESS__RLIMITINH, NULL);
2226         if (rc) {
2227                 /* protect against do_prlimit() */
2228                 task_lock(current);
2229                 for (i = 0; i < RLIM_NLIMITS; i++) {
2230                         rlim = current->signal->rlim + i;
2231                         initrlim = init_task.signal->rlim + i;
2232                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2233                 }
2234                 task_unlock(current);
2235                 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2236         }
2237 }
2238
2239 /*
2240  * Clean up the process immediately after the installation of new credentials
2241  * due to exec
2242  */
2243 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2244 {
2245         const struct task_security_struct *tsec = current_security();
2246         struct itimerval itimer;
2247         u32 osid, sid;
2248         int rc, i;
2249
2250         osid = tsec->osid;
2251         sid = tsec->sid;
2252
2253         if (sid == osid)
2254                 return;
2255
2256         /* Check whether the new SID can inherit signal state from the old SID.
2257          * If not, clear itimers to avoid subsequent signal generation and
2258          * flush and unblock signals.
2259          *
2260          * This must occur _after_ the task SID has been updated so that any
2261          * kill done after the flush will be checked against the new SID.
2262          */
2263         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2264         if (rc) {
2265                 memset(&itimer, 0, sizeof itimer);
2266                 for (i = 0; i < 3; i++)
2267                         do_setitimer(i, &itimer, NULL);
2268                 spin_lock_irq(&current->sighand->siglock);
2269                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2270                         __flush_signals(current);
2271                         flush_signal_handlers(current, 1);
2272                         sigemptyset(&current->blocked);
2273                 }
2274                 spin_unlock_irq(&current->sighand->siglock);
2275         }
2276
2277         /* Wake up the parent if it is waiting so that it can recheck
2278          * wait permission to the new task SID. */
2279         read_lock(&tasklist_lock);
2280         __wake_up_parent(current, current->real_parent);
2281         read_unlock(&tasklist_lock);
2282 }
2283
2284 /* superblock security operations */
2285
2286 static int selinux_sb_alloc_security(struct super_block *sb)
2287 {
2288         return superblock_alloc_security(sb);
2289 }
2290
2291 static void selinux_sb_free_security(struct super_block *sb)
2292 {
2293         superblock_free_security(sb);
2294 }
2295
2296 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2297 {
2298         if (plen > olen)
2299                 return 0;
2300
2301         return !memcmp(prefix, option, plen);
2302 }
2303
2304 static inline int selinux_option(char *option, int len)
2305 {
2306         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2307                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2308                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2309                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2310                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2311 }
2312
2313 static inline void take_option(char **to, char *from, int *first, int len)
2314 {
2315         if (!*first) {
2316                 **to = ',';
2317                 *to += 1;
2318         } else
2319                 *first = 0;
2320         memcpy(*to, from, len);
2321         *to += len;
2322 }
2323
2324 static inline void take_selinux_option(char **to, char *from, int *first,
2325                                        int len)
2326 {
2327         int current_size = 0;
2328
2329         if (!*first) {
2330                 **to = '|';
2331                 *to += 1;
2332         } else
2333                 *first = 0;
2334
2335         while (current_size < len) {
2336                 if (*from != '"') {
2337                         **to = *from;
2338                         *to += 1;
2339                 }
2340                 from += 1;
2341                 current_size += 1;
2342         }
2343 }
2344
2345 static int selinux_sb_copy_data(char *orig, char *copy)
2346 {
2347         int fnosec, fsec, rc = 0;
2348         char *in_save, *in_curr, *in_end;
2349         char *sec_curr, *nosec_save, *nosec;
2350         int open_quote = 0;
2351
2352         in_curr = orig;
2353         sec_curr = copy;
2354
2355         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2356         if (!nosec) {
2357                 rc = -ENOMEM;
2358                 goto out;
2359         }
2360
2361         nosec_save = nosec;
2362         fnosec = fsec = 1;
2363         in_save = in_end = orig;
2364
2365         do {
2366                 if (*in_end == '"')
2367                         open_quote = !open_quote;
2368                 if ((*in_end == ',' && open_quote == 0) ||
2369                                 *in_end == '\0') {
2370                         int len = in_end - in_curr;
2371
2372                         if (selinux_option(in_curr, len))
2373                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2374                         else
2375                                 take_option(&nosec, in_curr, &fnosec, len);
2376
2377                         in_curr = in_end + 1;
2378                 }
2379         } while (*in_end++);
2380
2381         strcpy(in_save, nosec_save);
2382         free_page((unsigned long)nosec_save);
2383 out:
2384         return rc;
2385 }
2386
2387 static int selinux_sb_remount(struct super_block *sb, void *data)
2388 {
2389         int rc, i, *flags;
2390         struct security_mnt_opts opts;
2391         char *secdata, **mount_options;
2392         struct superblock_security_struct *sbsec = sb->s_security;
2393
2394         if (!(sbsec->flags & SE_SBINITIALIZED))
2395                 return 0;
2396
2397         if (!data)
2398                 return 0;
2399
2400         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2401                 return 0;
2402
2403         security_init_mnt_opts(&opts);
2404         secdata = alloc_secdata();
2405         if (!secdata)
2406                 return -ENOMEM;
2407         rc = selinux_sb_copy_data(data, secdata);
2408         if (rc)
2409                 goto out_free_secdata;
2410
2411         rc = selinux_parse_opts_str(secdata, &opts);
2412         if (rc)
2413                 goto out_free_secdata;
2414
2415         mount_options = opts.mnt_opts;
2416         flags = opts.mnt_opts_flags;
2417
2418         for (i = 0; i < opts.num_mnt_opts; i++) {
2419                 u32 sid;
2420                 size_t len;
2421
2422                 if (flags[i] == SE_SBLABELSUPP)
2423                         continue;
2424                 len = strlen(mount_options[i]);
2425                 rc = security_context_to_sid(mount_options[i], len, &sid);
2426                 if (rc) {
2427                         printk(KERN_WARNING "SELinux: security_context_to_sid"
2428                                "(%s) failed for (dev %s, type %s) errno=%d\n",
2429                                mount_options[i], sb->s_id, sb->s_type->name, rc);
2430                         goto out_free_opts;
2431                 }
2432                 rc = -EINVAL;
2433                 switch (flags[i]) {
2434                 case FSCONTEXT_MNT:
2435                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2436                                 goto out_bad_option;
2437                         break;
2438                 case CONTEXT_MNT:
2439                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2440                                 goto out_bad_option;
2441                         break;
2442                 case ROOTCONTEXT_MNT: {
2443                         struct inode_security_struct *root_isec;
2444                         root_isec = sb->s_root->d_inode->i_security;
2445
2446                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2447                                 goto out_bad_option;
2448                         break;
2449                 }
2450                 case DEFCONTEXT_MNT:
2451                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2452                                 goto out_bad_option;
2453                         break;
2454                 default:
2455                         goto out_free_opts;
2456                 }
2457         }
2458
2459         rc = 0;
2460 out_free_opts:
2461         security_free_mnt_opts(&opts);
2462 out_free_secdata:
2463         free_secdata(secdata);
2464         return rc;
2465 out_bad_option:
2466         printk(KERN_WARNING "SELinux: unable to change security options "
2467                "during remount (dev %s, type=%s)\n", sb->s_id,
2468                sb->s_type->name);
2469         goto out_free_opts;
2470 }
2471
2472 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2473 {
2474         const struct cred *cred = current_cred();
2475         struct common_audit_data ad;
2476         int rc;
2477
2478         rc = superblock_doinit(sb, data);
2479         if (rc)
2480                 return rc;
2481
2482         /* Allow all mounts performed by the kernel */
2483         if (flags & MS_KERNMOUNT)
2484                 return 0;
2485
2486         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2487         ad.u.dentry = sb->s_root;
2488         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2489 }
2490
2491 static int selinux_sb_statfs(struct dentry *dentry)
2492 {
2493         const struct cred *cred = current_cred();
2494         struct common_audit_data ad;
2495
2496         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2497         ad.u.dentry = dentry->d_sb->s_root;
2498         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2499 }
2500
2501 static int selinux_mount(char *dev_name,
2502                          struct path *path,
2503                          char *type,
2504                          unsigned long flags,
2505                          void *data)
2506 {
2507         const struct cred *cred = current_cred();
2508
2509         if (flags & MS_REMOUNT)
2510                 return superblock_has_perm(cred, path->mnt->mnt_sb,
2511                                            FILESYSTEM__REMOUNT, NULL);
2512         else
2513                 return path_has_perm(cred, path, FILE__MOUNTON);
2514 }
2515
2516 static int selinux_umount(struct vfsmount *mnt, int flags)
2517 {
2518         const struct cred *cred = current_cred();
2519
2520         return superblock_has_perm(cred, mnt->mnt_sb,
2521                                    FILESYSTEM__UNMOUNT, NULL);
2522 }
2523
2524 /* inode security operations */
2525
2526 static int selinux_inode_alloc_security(struct inode *inode)
2527 {
2528         return inode_alloc_security(inode);
2529 }
2530
2531 static void selinux_inode_free_security(struct inode *inode)
2532 {
2533         inode_free_security(inode);
2534 }
2535
2536 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2537                                        const struct qstr *qstr, char **name,
2538                                        void **value, size_t *len)
2539 {
2540         const struct task_security_struct *tsec = current_security();
2541         struct inode_security_struct *dsec;
2542         struct superblock_security_struct *sbsec;
2543         u32 sid, newsid, clen;
2544         int rc;
2545         char *namep = NULL, *context;
2546
2547         dsec = dir->i_security;
2548         sbsec = dir->i_sb->s_security;
2549
2550         sid = tsec->sid;
2551         newsid = tsec->create_sid;
2552
2553         if ((sbsec->flags & SE_SBINITIALIZED) &&
2554             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2555                 newsid = sbsec->mntpoint_sid;
2556         else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2557                 rc = security_transition_sid(sid, dsec->sid,
2558                                              inode_mode_to_security_class(inode->i_mode),
2559                                              qstr, &newsid);
2560                 if (rc) {
2561                         printk(KERN_WARNING "%s:  "
2562                                "security_transition_sid failed, rc=%d (dev=%s "
2563                                "ino=%ld)\n",
2564                                __func__,
2565                                -rc, inode->i_sb->s_id, inode->i_ino);
2566                         return rc;
2567                 }
2568         }
2569
2570         /* Possibly defer initialization to selinux_complete_init. */
2571         if (sbsec->flags & SE_SBINITIALIZED) {
2572                 struct inode_security_struct *isec = inode->i_security;
2573                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2574                 isec->sid = newsid;
2575                 isec->initialized = 1;
2576         }
2577
2578         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2579                 return -EOPNOTSUPP;
2580
2581         if (name) {
2582                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2583                 if (!namep)
2584                         return -ENOMEM;
2585                 *name = namep;
2586         }
2587
2588         if (value && len) {
2589                 rc = security_sid_to_context_force(newsid, &context, &clen);
2590                 if (rc) {
2591                         kfree(namep);
2592                         return rc;
2593                 }
2594                 *value = context;
2595                 *len = clen;
2596         }
2597
2598         return 0;
2599 }
2600
2601 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2602 {
2603         return may_create(dir, dentry, SECCLASS_FILE);
2604 }
2605
2606 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2607 {
2608         return may_link(dir, old_dentry, MAY_LINK);
2609 }
2610
2611 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2612 {
2613         return may_link(dir, dentry, MAY_UNLINK);
2614 }
2615
2616 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2617 {
2618         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2619 }
2620
2621 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2622 {
2623         return may_create(dir, dentry, SECCLASS_DIR);
2624 }
2625
2626 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2627 {
2628         return may_link(dir, dentry, MAY_RMDIR);
2629 }
2630
2631 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2632 {
2633         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2634 }
2635
2636 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2637                                 struct inode *new_inode, struct dentry *new_dentry)
2638 {
2639         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2640 }
2641
2642 static int selinux_inode_readlink(struct dentry *dentry)
2643 {
2644         const struct cred *cred = current_cred();
2645
2646         return dentry_has_perm(cred, dentry, FILE__READ);
2647 }
2648
2649 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2650 {
2651         const struct cred *cred = current_cred();
2652
2653         return dentry_has_perm(cred, dentry, FILE__READ);
2654 }
2655
2656 static int selinux_inode_permission(struct inode *inode, int mask)
2657 {
2658         const struct cred *cred = current_cred();
2659         struct common_audit_data ad;
2660         u32 perms;
2661         bool from_access;
2662         unsigned flags = mask & MAY_NOT_BLOCK;
2663
2664         from_access = mask & MAY_ACCESS;
2665         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2666
2667         /* No permission to check.  Existence test. */
2668         if (!mask)
2669                 return 0;
2670
2671         COMMON_AUDIT_DATA_INIT(&ad, INODE);
2672         ad.u.inode = inode;
2673
2674         if (from_access)
2675                 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2676
2677         perms = file_mask_to_av(inode->i_mode, mask);
2678
2679         return inode_has_perm(cred, inode, perms, &ad, flags);
2680 }
2681
2682 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2683 {
2684         const struct cred *cred = current_cred();
2685         unsigned int ia_valid = iattr->ia_valid;
2686
2687         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2688         if (ia_valid & ATTR_FORCE) {
2689                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2690                               ATTR_FORCE);
2691                 if (!ia_valid)
2692                         return 0;
2693         }
2694
2695         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2696                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2697                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2698
2699         return dentry_has_perm(cred, dentry, FILE__WRITE);
2700 }
2701
2702 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2703 {
2704         const struct cred *cred = current_cred();
2705         struct path path;
2706
2707         path.dentry = dentry;
2708         path.mnt = mnt;
2709
2710         return path_has_perm(cred, &path, FILE__GETATTR);
2711 }
2712
2713 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2714 {
2715         const struct cred *cred = current_cred();
2716
2717         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2718                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2719                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2720                         if (!capable(CAP_SETFCAP))
2721                                 return -EPERM;
2722                 } else if (!capable(CAP_SYS_ADMIN)) {
2723                         /* A different attribute in the security namespace.
2724                            Restrict to administrator. */
2725                         return -EPERM;
2726                 }
2727         }
2728
2729         /* Not an attribute we recognize, so just check the
2730            ordinary setattr permission. */
2731         return dentry_has_perm(cred, dentry, FILE__SETATTR);
2732 }
2733
2734 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2735                                   const void *value, size_t size, int flags)
2736 {
2737         struct inode *inode = dentry->d_inode;
2738         struct inode_security_struct *isec = inode->i_security;
2739         struct superblock_security_struct *sbsec;
2740         struct common_audit_data ad;
2741         u32 newsid, sid = current_sid();
2742         int rc = 0;
2743
2744         if (strcmp(name, XATTR_NAME_SELINUX))
2745                 return selinux_inode_setotherxattr(dentry, name);
2746
2747         sbsec = inode->i_sb->s_security;
2748         if (!(sbsec->flags & SE_SBLABELSUPP))
2749                 return -EOPNOTSUPP;
2750
2751         if (!inode_owner_or_capable(inode))
2752                 return -EPERM;
2753
2754         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2755         ad.u.dentry = dentry;
2756
2757         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2758                           FILE__RELABELFROM, &ad);
2759         if (rc)
2760                 return rc;
2761
2762         rc = security_context_to_sid(value, size, &newsid);
2763         if (rc == -EINVAL) {
2764                 if (!capable(CAP_MAC_ADMIN))
2765                         return rc;
2766                 rc = security_context_to_sid_force(value, size, &newsid);
2767         }
2768         if (rc)
2769                 return rc;
2770
2771         rc = avc_has_perm(sid, newsid, isec->sclass,
2772                           FILE__RELABELTO, &ad);
2773         if (rc)
2774                 return rc;
2775
2776         rc = security_validate_transition(isec->sid, newsid, sid,
2777                                           isec->sclass);
2778         if (rc)
2779                 return rc;
2780
2781         return avc_has_perm(newsid,
2782                             sbsec->sid,
2783                             SECCLASS_FILESYSTEM,
2784                             FILESYSTEM__ASSOCIATE,
2785                             &ad);
2786 }
2787
2788 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2789                                         const void *value, size_t size,
2790                                         int flags)
2791 {
2792         struct inode *inode = dentry->d_inode;
2793         struct inode_security_struct *isec = inode->i_security;
2794         u32 newsid;
2795         int rc;
2796
2797         if (strcmp(name, XATTR_NAME_SELINUX)) {
2798                 /* Not an attribute we recognize, so nothing to do. */
2799                 return;
2800         }
2801
2802         rc = security_context_to_sid_force(value, size, &newsid);
2803         if (rc) {
2804                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2805                        "for (%s, %lu), rc=%d\n",
2806                        inode->i_sb->s_id, inode->i_ino, -rc);
2807                 return;
2808         }
2809
2810         isec->sid = newsid;
2811         return;
2812 }
2813
2814 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2815 {
2816         const struct cred *cred = current_cred();
2817
2818         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2819 }
2820
2821 static int selinux_inode_listxattr(struct dentry *dentry)
2822 {
2823         const struct cred *cred = current_cred();
2824
2825         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2826 }
2827
2828 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2829 {
2830         if (strcmp(name, XATTR_NAME_SELINUX))
2831                 return selinux_inode_setotherxattr(dentry, name);
2832
2833         /* No one is allowed to remove a SELinux security label.
2834            You can change the label, but all data must be labeled. */
2835         return -EACCES;
2836 }
2837
2838 /*
2839  * Copy the inode security context value to the user.
2840  *
2841  * Permission check is handled by selinux_inode_getxattr hook.
2842  */
2843 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2844 {
2845         u32 size;
2846         int error;
2847         char *context = NULL;
2848         struct inode_security_struct *isec = inode->i_security;
2849
2850         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2851                 return -EOPNOTSUPP;
2852
2853         /*
2854          * If the caller has CAP_MAC_ADMIN, then get the raw context
2855          * value even if it is not defined by current policy; otherwise,
2856          * use the in-core value under current policy.
2857          * Use the non-auditing forms of the permission checks since
2858          * getxattr may be called by unprivileged processes commonly
2859          * and lack of permission just means that we fall back to the
2860          * in-core context value, not a denial.
2861          */
2862         error = selinux_capable(current, current_cred(),
2863                                 &init_user_ns, CAP_MAC_ADMIN,
2864                                 SECURITY_CAP_NOAUDIT);
2865         if (!error)
2866                 error = security_sid_to_context_force(isec->sid, &context,
2867                                                       &size);
2868         else
2869                 error = security_sid_to_context(isec->sid, &context, &size);
2870         if (error)
2871                 return error;
2872         error = size;
2873         if (alloc) {
2874                 *buffer = context;
2875                 goto out_nofree;
2876         }
2877         kfree(context);
2878 out_nofree:
2879         return error;
2880 }
2881
2882 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2883                                      const void *value, size_t size, int flags)
2884 {
2885         struct inode_security_struct *isec = inode->i_security;
2886         u32 newsid;
2887         int rc;
2888
2889         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2890                 return -EOPNOTSUPP;
2891
2892         if (!value || !size)
2893                 return -EACCES;
2894
2895         rc = security_context_to_sid((void *)value, size, &newsid);
2896         if (rc)
2897                 return rc;
2898
2899         isec->sid = newsid;
2900         isec->initialized = 1;
2901         return 0;
2902 }
2903
2904 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2905 {
2906         const int len = sizeof(XATTR_NAME_SELINUX);
2907         if (buffer && len <= buffer_size)
2908                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2909         return len;
2910 }
2911
2912 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2913 {
2914         struct inode_security_struct *isec = inode->i_security;
2915         *secid = isec->sid;
2916 }
2917
2918 /* file security operations */
2919
2920 static int selinux_revalidate_file_permission(struct file *file, int mask)
2921 {
2922         const struct cred *cred = current_cred();
2923         struct inode *inode = file->f_path.dentry->d_inode;
2924
2925         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2926         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2927                 mask |= MAY_APPEND;
2928
2929         return file_has_perm(cred, file,
2930                              file_mask_to_av(inode->i_mode, mask));
2931 }
2932
2933 static int selinux_file_permission(struct file *file, int mask)
2934 {
2935         struct inode *inode = file->f_path.dentry->d_inode;
2936         struct file_security_struct *fsec = file->f_security;
2937         struct inode_security_struct *isec = inode->i_security;
2938         u32 sid = current_sid();
2939
2940         if (!mask)
2941                 /* No permission to check.  Existence test. */
2942                 return 0;
2943
2944         if (sid == fsec->sid && fsec->isid == isec->sid &&
2945             fsec->pseqno == avc_policy_seqno())
2946                 /* No change since dentry_open check. */
2947                 return 0;
2948
2949         return selinux_revalidate_file_permission(file, mask);
2950 }
2951
2952 static int selinux_file_alloc_security(struct file *file)
2953 {
2954         return file_alloc_security(file);
2955 }
2956
2957 static void selinux_file_free_security(struct file *file)
2958 {
2959         file_free_security(file);
2960 }
2961
2962 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2963                               unsigned long arg)
2964 {
2965         const struct cred *cred = current_cred();
2966         int error = 0;
2967
2968         switch (cmd) {
2969         case FIONREAD:
2970         /* fall through */
2971         case FIBMAP:
2972         /* fall through */
2973         case FIGETBSZ:
2974         /* fall through */
2975         case EXT2_IOC_GETFLAGS:
2976         /* fall through */
2977         case EXT2_IOC_GETVERSION:
2978                 error = file_has_perm(cred, file, FILE__GETATTR);
2979                 break;
2980
2981         case EXT2_IOC_SETFLAGS:
2982         /* fall through */
2983         case EXT2_IOC_SETVERSION:
2984                 error = file_has_perm(cred, file, FILE__SETATTR);
2985                 break;
2986
2987         /* sys_ioctl() checks */
2988         case FIONBIO:
2989         /* fall through */
2990         case FIOASYNC:
2991                 error = file_has_perm(cred, file, 0);
2992                 break;
2993
2994         case KDSKBENT:
2995         case KDSKBSENT:
2996                 error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG,
2997                                         SECURITY_CAP_AUDIT);
2998                 break;
2999
3000         /* default case assumes that the command will go
3001          * to the file's ioctl() function.
3002          */
3003         default:
3004                 error = file_has_perm(cred, file, FILE__IOCTL);
3005         }
3006         return error;
3007 }
3008
3009 static int default_noexec;
3010
3011 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3012 {
3013         const struct cred *cred = current_cred();
3014         int rc = 0;
3015
3016         if (default_noexec &&
3017             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3018                 /*
3019                  * We are making executable an anonymous mapping or a
3020                  * private file mapping that will also be writable.
3021                  * This has an additional check.
3022                  */
3023                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3024                 if (rc)
3025                         goto error;
3026         }
3027
3028         if (file) {
3029                 /* read access is always possible with a mapping */
3030                 u32 av = FILE__READ;
3031
3032                 /* write access only matters if the mapping is shared */
3033                 if (shared && (prot & PROT_WRITE))
3034                         av |= FILE__WRITE;
3035
3036                 if (prot & PROT_EXEC)
3037                         av |= FILE__EXECUTE;
3038
3039                 return file_has_perm(cred, file, av);
3040         }
3041
3042 error:
3043         return rc;
3044 }
3045
3046 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3047                              unsigned long prot, unsigned long flags,
3048                              unsigned long addr, unsigned long addr_only)
3049 {
3050         int rc = 0;
3051         u32 sid = current_sid();
3052
3053         /*
3054          * notice that we are intentionally putting the SELinux check before
3055          * the secondary cap_file_mmap check.  This is such a likely attempt
3056          * at bad behaviour/exploit that we always want to get the AVC, even
3057          * if DAC would have also denied the operation.
3058          */
3059         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3060                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3061                                   MEMPROTECT__MMAP_ZERO, NULL);
3062                 if (rc)
3063                         return rc;
3064         }
3065
3066         /* do DAC check on address space usage */
3067         rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3068         if (rc || addr_only)
3069                 return rc;
3070
3071         if (selinux_checkreqprot)
3072                 prot = reqprot;
3073
3074         return file_map_prot_check(file, prot,
3075                                    (flags & MAP_TYPE) == MAP_SHARED);
3076 }
3077
3078 static int selinux_file_mprotect(struct vm_area_struct *vma,
3079                                  unsigned long reqprot,
3080                                  unsigned long prot)
3081 {
3082         const struct cred *cred = current_cred();
3083
3084         if (selinux_checkreqprot)
3085                 prot = reqprot;
3086
3087         if (default_noexec &&
3088             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3089                 int rc = 0;
3090                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3091                     vma->vm_end <= vma->vm_mm->brk) {
3092                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3093                 } else if (!vma->vm_file &&
3094                            vma->vm_start <= vma->vm_mm->start_stack &&
3095                            vma->vm_end >= vma->vm_mm->start_stack) {
3096                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3097                 } else if (vma->vm_file && vma->anon_vma) {
3098                         /*
3099                          * We are making executable a file mapping that has
3100                          * had some COW done. Since pages might have been
3101                          * written, check ability to execute the possibly
3102                          * modified content.  This typically should only
3103                          * occur for text relocations.
3104                          */
3105                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3106                 }
3107                 if (rc)
3108                         return rc;
3109         }
3110
3111         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3112 }
3113
3114 static int selinux_file_lock(struct file *file, unsigned int cmd)
3115 {
3116         const struct cred *cred = current_cred();
3117
3118         return file_has_perm(cred, file, FILE__LOCK);
3119 }
3120
3121 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3122                               unsigned long arg)
3123 {
3124         const struct cred *cred = current_cred();
3125         int err = 0;
3126
3127         switch (cmd) {
3128         case F_SETFL:
3129                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3130                         err = -EINVAL;
3131                         break;
3132                 }
3133
3134                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3135                         err = file_has_perm(cred, file, FILE__WRITE);
3136                         break;
3137                 }
3138                 /* fall through */
3139         case F_SETOWN:
3140         case F_SETSIG:
3141         case F_GETFL:
3142         case F_GETOWN:
3143         case F_GETSIG:
3144                 /* Just check FD__USE permission */
3145                 err = file_has_perm(cred, file, 0);
3146                 break;
3147         case F_GETLK:
3148         case F_SETLK:
3149         case F_SETLKW:
3150 #if BITS_PER_LONG == 32
3151         case F_GETLK64:
3152         case F_SETLK64:
3153         case F_SETLKW64:
3154 #endif
3155                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3156                         err = -EINVAL;
3157                         break;
3158                 }
3159                 err = file_has_perm(cred, file, FILE__LOCK);
3160                 break;
3161         }
3162
3163         return err;
3164 }
3165
3166 static int selinux_file_set_fowner(struct file *file)
3167 {
3168         struct file_security_struct *fsec;
3169
3170         fsec = file->f_security;
3171         fsec->fown_sid = current_sid();
3172
3173         return 0;
3174 }
3175
3176 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3177                                        struct fown_struct *fown, int signum)
3178 {
3179         struct file *file;
3180         u32 sid = task_sid(tsk);
3181         u32 perm;
3182         struct file_security_struct *fsec;
3183
3184         /* struct fown_struct is never outside the context of a struct file */
3185         file = container_of(fown, struct file, f_owner);
3186
3187         fsec = file->f_security;
3188
3189         if (!signum)
3190                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3191         else
3192                 perm = signal_to_av(signum);
3193
3194         return avc_has_perm(fsec->fown_sid, sid,
3195                             SECCLASS_PROCESS, perm, NULL);
3196 }
3197
3198 static int selinux_file_receive(struct file *file)
3199 {
3200         const struct cred *cred = current_cred();
3201
3202         return file_has_perm(cred, file, file_to_av(file));
3203 }
3204
3205 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3206 {
3207         struct file_security_struct *fsec;
3208         struct inode *inode;
3209         struct inode_security_struct *isec;
3210
3211         inode = file->f_path.dentry->d_inode;
3212         fsec = file->f_security;
3213         isec = inode->i_security;
3214         /*
3215          * Save inode label and policy sequence number
3216          * at open-time so that selinux_file_permission
3217          * can determine whether revalidation is necessary.
3218          * Task label is already saved in the file security
3219          * struct as its SID.
3220          */
3221         fsec->isid = isec->sid;
3222         fsec->pseqno = avc_policy_seqno();
3223         /*
3224          * Since the inode label or policy seqno may have changed
3225          * between the selinux_inode_permission check and the saving
3226          * of state above, recheck that access is still permitted.
3227          * Otherwise, access might never be revalidated against the
3228          * new inode label or new policy.
3229          * This check is not redundant - do not remove.
3230          */
3231         return inode_has_perm_noadp(cred, inode, open_file_to_av(file), 0);
3232 }
3233
3234 /* task security operations */
3235
3236 static int selinux_task_create(unsigned long clone_flags)
3237 {
3238         return current_has_perm(current, PROCESS__FORK);
3239 }
3240
3241 /*
3242  * allocate the SELinux part of blank credentials
3243  */
3244 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3245 {
3246         struct task_security_struct *tsec;
3247
3248         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3249         if (!tsec)
3250                 return -ENOMEM;
3251
3252         cred->security = tsec;
3253         return 0;
3254 }
3255
3256 /*
3257  * detach and free the LSM part of a set of credentials
3258  */
3259 static void selinux_cred_free(struct cred *cred)
3260 {
3261         struct task_security_struct *tsec = cred->security;
3262
3263         /*
3264          * cred->security == NULL if security_cred_alloc_blank() or
3265          * security_prepare_creds() returned an error.
3266          */
3267         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3268         cred->security = (void *) 0x7UL;
3269         kfree(tsec);
3270 }
3271
3272 /*
3273  * prepare a new set of credentials for modification
3274  */
3275 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3276                                 gfp_t gfp)
3277 {
3278         const struct task_security_struct *old_tsec;
3279         struct task_security_struct *tsec;
3280
3281         old_tsec = old->security;
3282
3283         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3284         if (!tsec)
3285                 return -ENOMEM;
3286
3287         new->security = tsec;
3288         return 0;
3289 }
3290
3291 /*
3292  * transfer the SELinux data to a blank set of creds
3293  */
3294 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3295 {
3296         const struct task_security_struct *old_tsec = old->security;
3297         struct task_security_struct *tsec = new->security;
3298
3299         *tsec = *old_tsec;
3300 }
3301
3302 /*
3303  * set the security data for a kernel service
3304  * - all the creation contexts are set to unlabelled
3305  */
3306 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3307 {
3308         struct task_security_struct *tsec = new->security;
3309         u32 sid = current_sid();
3310         int ret;
3311
3312         ret = avc_has_perm(sid, secid,
3313                            SECCLASS_KERNEL_SERVICE,
3314                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3315                            NULL);
3316         if (ret == 0) {
3317                 tsec->sid = secid;
3318                 tsec->create_sid = 0;
3319                 tsec->keycreate_sid = 0;
3320                 tsec->sockcreate_sid = 0;
3321         }
3322         return ret;
3323 }
3324
3325 /*
3326  * set the file creation context in a security record to the same as the
3327  * objective context of the specified inode
3328  */
3329 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3330 {
3331         struct inode_security_struct *isec = inode->i_security;
3332         struct task_security_struct *tsec = new->security;
3333         u32 sid = current_sid();
3334         int ret;
3335
3336         ret = avc_has_perm(sid, isec->sid,
3337                            SECCLASS_KERNEL_SERVICE,
3338                            KERNEL_SERVICE__CREATE_FILES_AS,
3339                            NULL);
3340
3341         if (ret == 0)
3342                 tsec->create_sid = isec->sid;
3343         return ret;
3344 }
3345
3346 static int selinux_kernel_module_request(char *kmod_name)
3347 {
3348         u32 sid;
3349         struct common_audit_data ad;
3350
3351         sid = task_sid(current);
3352
3353         COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3354         ad.u.kmod_name = kmod_name;
3355
3356         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3357                             SYSTEM__MODULE_REQUEST, &ad);
3358 }
3359
3360 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3361 {
3362         return current_has_perm(p, PROCESS__SETPGID);
3363 }
3364
3365 static int selinux_task_getpgid(struct task_struct *p)
3366 {
3367         return current_has_perm(p, PROCESS__GETPGID);
3368 }
3369
3370 static int selinux_task_getsid(struct task_struct *p)
3371 {
3372         return current_has_perm(p, PROCESS__GETSESSION);
3373 }
3374
3375 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3376 {
3377         *secid = task_sid(p);
3378 }
3379
3380 static int selinux_task_setnice(struct task_struct *p, int nice)
3381 {
3382         int rc;
3383
3384         rc = cap_task_setnice(p, nice);
3385         if (rc)
3386                 return rc;
3387
3388         return current_has_perm(p, PROCESS__SETSCHED);
3389 }
3390
3391 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3392 {
3393         int rc;
3394
3395         rc = cap_task_setioprio(p, ioprio);
3396         if (rc)
3397                 return rc;
3398
3399         return current_has_perm(p, PROCESS__SETSCHED);
3400 }
3401
3402 static int selinux_task_getioprio(struct task_struct *p)
3403 {
3404         return current_has_perm(p, PROCESS__GETSCHED);
3405 }
3406
3407 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3408                 struct rlimit *new_rlim)
3409 {
3410         struct rlimit *old_rlim = p->signal->rlim + resource;
3411
3412         /* Control the ability to change the hard limit (whether
3413            lowering or raising it), so that the hard limit can
3414            later be used as a safe reset point for the soft limit
3415            upon context transitions.  See selinux_bprm_committing_creds. */
3416         if (old_rlim->rlim_max != new_rlim->rlim_max)
3417                 return current_has_perm(p, PROCESS__SETRLIMIT);
3418
3419         return 0;
3420 }
3421
3422 static int selinux_task_setscheduler(struct task_struct *p)
3423 {
3424         int rc;
3425
3426         rc = cap_task_setscheduler(p);
3427         if (rc)
3428                 return rc;
3429
3430         return current_has_perm(p, PROCESS__SETSCHED);
3431 }
3432
3433 static int selinux_task_getscheduler(struct task_struct *p)
3434 {
3435         return current_has_perm(p, PROCESS__GETSCHED);
3436 }
3437
3438 static int selinux_task_movememory(struct task_struct *p)
3439 {
3440         return current_has_perm(p, PROCESS__SETSCHED);
3441 }
3442
3443 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3444                                 int sig, u32 secid)
3445 {
3446         u32 perm;
3447         int rc;
3448
3449         if (!sig)
3450                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3451         else
3452                 perm = signal_to_av(sig);
3453         if (secid)
3454                 rc = avc_has_perm(secid, task_sid(p),
3455                                   SECCLASS_PROCESS, perm, NULL);
3456         else
3457                 rc = current_has_perm(p, perm);
3458         return rc;
3459 }
3460
3461 static int selinux_task_wait(struct task_struct *p)
3462 {
3463         return task_has_perm(p, current, PROCESS__SIGCHLD);
3464 }
3465
3466 static void selinux_task_to_inode(struct task_struct *p,
3467                                   struct inode *inode)
3468 {
3469         struct inode_security_struct *isec = inode->i_security;
3470         u32 sid = task_sid(p);
3471
3472         isec->sid = sid;
3473         isec->initialized = 1;
3474 }
3475
3476 /* Returns error only if unable to parse addresses */
3477 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3478                         struct common_audit_data *ad, u8 *proto)
3479 {
3480         int offset, ihlen, ret = -EINVAL;
3481         struct iphdr _iph, *ih;
3482
3483         offset = skb_network_offset(skb);
3484         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3485         if (ih == NULL)
3486                 goto out;
3487
3488         ihlen = ih->ihl * 4;
3489         if (ihlen < sizeof(_iph))
3490                 goto out;
3491
3492         ad->u.net.v4info.saddr = ih->saddr;
3493         ad->u.net.v4info.daddr = ih->daddr;
3494         ret = 0;
3495
3496         if (proto)
3497                 *proto = ih->protocol;
3498
3499         switch (ih->protocol) {
3500         case IPPROTO_TCP: {
3501                 struct tcphdr _tcph, *th;
3502
3503                 if (ntohs(ih->frag_off) & IP_OFFSET)
3504                         break;
3505
3506                 offset += ihlen;
3507                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3508                 if (th == NULL)
3509                         break;
3510
3511                 ad->u.net.sport = th->source;
3512                 ad->u.net.dport = th->dest;
3513                 break;
3514         }
3515
3516         case IPPROTO_UDP: {
3517                 struct udphdr _udph, *uh;
3518
3519                 if (ntohs(ih->frag_off) & IP_OFFSET)
3520                         break;
3521
3522                 offset += ihlen;
3523                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3524                 if (uh == NULL)
3525                         break;
3526
3527                 ad->u.net.sport = uh->source;
3528                 ad->u.net.dport = uh->dest;
3529                 break;
3530         }
3531
3532         case IPPROTO_DCCP: {
3533                 struct dccp_hdr _dccph, *dh;
3534
3535                 if (ntohs(ih->frag_off) & IP_OFFSET)
3536                         break;
3537
3538                 offset += ihlen;
3539                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3540                 if (dh == NULL)
3541                         break;
3542
3543                 ad->u.net.sport = dh->dccph_sport;
3544                 ad->u.net.dport = dh->dccph_dport;
3545                 break;
3546         }
3547
3548         default:
3549                 break;
3550         }
3551 out:
3552         return ret;
3553 }
3554
3555 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3556
3557 /* Returns error only if unable to parse addresses */
3558 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3559                         struct common_audit_data *ad, u8 *proto)
3560 {
3561         u8 nexthdr;
3562         int ret = -EINVAL, offset;
3563         struct ipv6hdr _ipv6h, *ip6;
3564
3565         offset = skb_network_offset(skb);
3566         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3567         if (ip6 == NULL)
3568                 goto out;
3569
3570         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3571         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3572         ret = 0;
3573
3574         nexthdr = ip6->nexthdr;
3575         offset += sizeof(_ipv6h);
3576         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3577         if (offset < 0)
3578                 goto out;
3579
3580         if (proto)
3581                 *proto = nexthdr;
3582
3583         switch (nexthdr) {
3584         case IPPROTO_TCP: {
3585                 struct tcphdr _tcph, *th;
3586
3587                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3588                 if (th == NULL)
3589                         break;
3590
3591                 ad->u.net.sport = th->source;
3592                 ad->u.net.dport = th->dest;
3593                 break;
3594         }
3595
3596         case IPPROTO_UDP: {
3597                 struct udphdr _udph, *uh;
3598
3599                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3600                 if (uh == NULL)
3601                         break;
3602
3603                 ad->u.net.sport = uh->source;
3604                 ad->u.net.dport = uh->dest;
3605                 break;
3606         }
3607
3608         case IPPROTO_DCCP: {
3609                 struct dccp_hdr _dccph, *dh;
3610
3611                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3612                 if (dh == NULL)
3613                         break;
3614
3615                 ad->u.net.sport = dh->dccph_sport;
3616                 ad->u.net.dport = dh->dccph_dport;
3617                 break;
3618         }
3619
3620         /* includes fragments */
3621         default:
3622                 break;
3623         }
3624 out:
3625         return ret;
3626 }
3627
3628 #endif /* IPV6 */
3629
3630 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3631                              char **_addrp, int src, u8 *proto)
3632 {
3633         char *addrp;
3634         int ret;
3635
3636         switch (ad->u.net.family) {
3637         case PF_INET:
3638                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3639                 if (ret)
3640                         goto parse_error;
3641                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3642                                        &ad->u.net.v4info.daddr);
3643                 goto okay;
3644
3645 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3646         case PF_INET6:
3647                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3648                 if (ret)
3649                         goto parse_error;
3650                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3651                                        &ad->u.net.v6info.daddr);
3652                 goto okay;
3653 #endif  /* IPV6 */
3654         default:
3655                 addrp = NULL;
3656                 goto okay;
3657         }
3658
3659 parse_error:
3660         printk(KERN_WARNING
3661                "SELinux: failure in selinux_parse_skb(),"
3662                " unable to parse packet\n");
3663         return ret;
3664
3665 okay:
3666         if (_addrp)
3667                 *_addrp = addrp;
3668         return 0;
3669 }
3670
3671 /**
3672  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3673  * @skb: the packet
3674  * @family: protocol family
3675  * @sid: the packet's peer label SID
3676  *
3677  * Description:
3678  * Check the various different forms of network peer labeling and determine
3679  * the peer label/SID for the packet; most of the magic actually occurs in
3680  * the security server function security_net_peersid_cmp().  The function
3681  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3682  * or -EACCES if @sid is invalid due to inconsistencies with the different
3683  * peer labels.
3684  *
3685  */
3686 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3687 {
3688         int err;
3689         u32 xfrm_sid;
3690         u32 nlbl_sid;
3691         u32 nlbl_type;
3692
3693         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3694         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3695
3696         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3697         if (unlikely(err)) {
3698                 printk(KERN_WARNING
3699                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3700                        " unable to determine packet's peer label\n");
3701                 return -EACCES;
3702         }
3703
3704         return 0;
3705 }
3706
3707 /* socket security operations */
3708
3709 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3710                                  u16 secclass, u32 *socksid)
3711 {
3712         if (tsec->sockcreate_sid > SECSID_NULL) {
3713                 *socksid = tsec->sockcreate_sid;
3714                 return 0;
3715         }
3716
3717         return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3718                                        socksid);
3719 }
3720
3721 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3722 {
3723         struct sk_security_struct *sksec = sk->sk_security;
3724         struct common_audit_data ad;
3725         u32 tsid = task_sid(task);
3726
3727         if (sksec->sid == SECINITSID_KERNEL)
3728                 return 0;
3729
3730         COMMON_AUDIT_DATA_INIT(&ad, NET);
3731         ad.u.net.sk = sk;
3732
3733         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3734 }
3735
3736 static int selinux_socket_create(int family, int type,
3737                                  int protocol, int kern)
3738 {
3739         const struct task_security_struct *tsec = current_security();
3740         u32 newsid;
3741         u16 secclass;
3742         int rc;
3743
3744         if (kern)
3745                 return 0;
3746
3747         secclass = socket_type_to_security_class(family, type, protocol);
3748         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3749         if (rc)
3750                 return rc;
3751
3752         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3753 }
3754
3755 static int selinux_socket_post_create(struct socket *sock, int family,
3756                                       int type, int protocol, int kern)
3757 {
3758         const struct task_security_struct *tsec = current_security();
3759         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3760         struct sk_security_struct *sksec;
3761         int err = 0;
3762
3763         isec->sclass = socket_type_to_security_class(family, type, protocol);
3764
3765         if (kern)
3766                 isec->sid = SECINITSID_KERNEL;
3767         else {
3768                 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3769                 if (err)
3770                         return err;
3771         }
3772
3773         isec->initialized = 1;
3774
3775         if (sock->sk) {
3776                 sksec = sock->sk->sk_security;
3777                 sksec->sid = isec->sid;
3778                 sksec->sclass = isec->sclass;
3779                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3780         }
3781
3782         return err;
3783 }
3784
3785 /* Range of port numbers used to automatically bind.
3786    Need to determine whether we should perform a name_bind
3787    permission check between the socket and the port number. */
3788
3789 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3790 {
3791         struct sock *sk = sock->sk;
3792         u16 family;
3793         int err;
3794
3795         err = sock_has_perm(current, sk, SOCKET__BIND);
3796         if (err)
3797                 goto out;
3798
3799         /*
3800          * If PF_INET or PF_INET6, check name_bind permission for the port.
3801          * Multiple address binding for SCTP is not supported yet: we just
3802          * check the first address now.
3803          */
3804         family = sk->sk_family;
3805         if (family == PF_INET || family == PF_INET6) {
3806                 char *addrp;
3807                 struct sk_security_struct *sksec = sk->sk_security;
3808                 struct common_audit_data ad;
3809                 struct sockaddr_in *addr4 = NULL;
3810                 struct sockaddr_in6 *addr6 = NULL;
3811                 unsigned short snum;
3812                 u32 sid, node_perm;
3813
3814                 if (family == PF_INET) {
3815                         addr4 = (struct sockaddr_in *)address;
3816                         snum = ntohs(addr4->sin_port);
3817                         addrp = (char *)&addr4->sin_addr.s_addr;
3818                 } else {
3819                         addr6 = (struct sockaddr_in6 *)address;
3820                         snum = ntohs(addr6->sin6_port);
3821                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3822                 }
3823
3824                 if (snum) {
3825                         int low, high;
3826
3827                         inet_get_local_port_range(&low, &high);
3828
3829                         if (snum < max(PROT_SOCK, low) || snum > high) {
3830                                 err = sel_netport_sid(sk->sk_protocol,
3831                                                       snum, &sid);
3832                                 if (err)
3833                                         goto out;
3834                                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3835                                 ad.u.net.sport = htons(snum);
3836                                 ad.u.net.family = family;
3837                                 err = avc_has_perm(sksec->sid, sid,
3838                                                    sksec->sclass,
3839                                                    SOCKET__NAME_BIND, &ad);
3840                                 if (err)
3841                                         goto out;
3842                         }
3843                 }
3844
3845                 switch (sksec->sclass) {
3846                 case SECCLASS_TCP_SOCKET:
3847                         node_perm = TCP_SOCKET__NODE_BIND;
3848                         break;
3849
3850                 case SECCLASS_UDP_SOCKET:
3851                         node_perm = UDP_SOCKET__NODE_BIND;
3852                         break;
3853
3854                 case SECCLASS_DCCP_SOCKET:
3855                         node_perm = DCCP_SOCKET__NODE_BIND;
3856                         break;
3857
3858                 default:
3859                         node_perm = RAWIP_SOCKET__NODE_BIND;
3860                         break;
3861                 }
3862
3863                 err = sel_netnode_sid(addrp, family, &sid);
3864                 if (err)
3865                         goto out;
3866
3867                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3868                 ad.u.net.sport = htons(snum);
3869                 ad.u.net.family = family;
3870
3871                 if (family == PF_INET)
3872                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3873                 else
3874                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3875
3876                 err = avc_has_perm(sksec->sid, sid,
3877                                    sksec->sclass, node_perm, &ad);
3878                 if (err)
3879                         goto out;
3880         }
3881 out:
3882         return err;
3883 }
3884
3885 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3886 {
3887         struct sock *sk = sock->sk;
3888         struct sk_security_struct *sksec = sk->sk_security;
3889         int err;
3890
3891         err = sock_has_perm(current, sk, SOCKET__CONNECT);
3892         if (err)
3893                 return err;
3894
3895         /*
3896          * If a TCP or DCCP socket, check name_connect permission for the port.
3897          */
3898         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3899             sksec->sclass == SECCLASS_DCCP_SOCKET) {
3900                 struct common_audit_data ad;
3901                 struct sockaddr_in *addr4 = NULL;
3902                 struct sockaddr_in6 *addr6 = NULL;
3903                 unsigned short snum;
3904                 u32 sid, perm;
3905
3906                 if (sk->sk_family == PF_INET) {
3907                         addr4 = (struct sockaddr_in *)address;
3908                         if (addrlen < sizeof(struct sockaddr_in))
3909                                 return -EINVAL;
3910                         snum = ntohs(addr4->sin_port);
3911                 } else {
3912                         addr6 = (struct sockaddr_in6 *)address;
3913                         if (addrlen < SIN6_LEN_RFC2133)
3914                                 return -EINVAL;
3915                         snum = ntohs(addr6->sin6_port);
3916                 }
3917
3918                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3919                 if (err)
3920                         goto out;
3921
3922                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3923                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3924
3925                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3926                 ad.u.net.dport = htons(snum);
3927                 ad.u.net.family = sk->sk_family;
3928                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3929                 if (err)
3930                         goto out;
3931         }
3932
3933         err = selinux_netlbl_socket_connect(sk, address);
3934
3935 out:
3936         return err;
3937 }
3938
3939 static int selinux_socket_listen(struct socket *sock, int backlog)
3940 {
3941         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3942 }
3943
3944 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3945 {
3946         int err;
3947         struct inode_security_struct *isec;
3948         struct inode_security_struct *newisec;
3949
3950         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3951         if (err)
3952                 return err;
3953
3954         newisec = SOCK_INODE(newsock)->i_security;
3955
3956         isec = SOCK_INODE(sock)->i_security;
3957         newisec->sclass = isec->sclass;
3958         newisec->sid = isec->sid;
3959         newisec->initialized = 1;
3960
3961         return 0;
3962 }
3963
3964 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3965                                   int size)
3966 {
3967         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3968 }
3969
3970 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3971                                   int size, int flags)
3972 {
3973         return sock_has_perm(current, sock->sk, SOCKET__READ);
3974 }
3975
3976 static int selinux_socket_getsockname(struct socket *sock)
3977 {
3978         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3979 }
3980
3981 static int selinux_socket_getpeername(struct socket *sock)
3982 {
3983         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3984 }
3985
3986 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3987 {
3988         int err;
3989
3990         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3991         if (err)
3992                 return err;
3993
3994         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3995 }
3996
3997 static int selinux_socket_getsockopt(struct socket *sock, int level,
3998                                      int optname)
3999 {
4000         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4001 }
4002
4003 static int selinux_socket_shutdown(struct socket *sock, int how)
4004 {
4005         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4006 }
4007
4008 static int selinux_socket_unix_stream_connect(struct sock *sock,
4009                                               struct sock *other,
4010                                               struct sock *newsk)
4011 {
4012         struct sk_security_struct *sksec_sock = sock->sk_security;
4013         struct sk_security_struct *sksec_other = other->sk_security;
4014         struct sk_security_struct *sksec_new = newsk->sk_security;
4015         struct common_audit_data ad;
4016         int err;
4017
4018         COMMON_AUDIT_DATA_INIT(&ad, NET);
4019         ad.u.net.sk = other;
4020
4021         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4022                            sksec_other->sclass,
4023                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4024         if (err)
4025                 return err;
4026
4027         /* server child socket */
4028         sksec_new->peer_sid = sksec_sock->sid;
4029         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4030                                     &sksec_new->sid);
4031         if (err)
4032                 return err;
4033
4034         /* connecting socket */
4035         sksec_sock->peer_sid = sksec_new->sid;
4036
4037         return 0;
4038 }
4039
4040 static int selinux_socket_unix_may_send(struct socket *sock,
4041                                         struct socket *other)
4042 {
4043         struct sk_security_struct *ssec = sock->sk->sk_security;
4044         struct sk_security_struct *osec = other->sk->sk_security;
4045         struct common_audit_data ad;
4046
4047         COMMON_AUDIT_DATA_INIT(&ad, NET);
4048         ad.u.net.sk = other->sk;
4049
4050         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4051                             &ad);
4052 }
4053
4054 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4055                                     u32 peer_sid,
4056                                     struct common_audit_data *ad)
4057 {
4058         int err;
4059         u32 if_sid;
4060         u32 node_sid;
4061
4062         err = sel_netif_sid(ifindex, &if_sid);
4063         if (err)
4064                 return err;
4065         err = avc_has_perm(peer_sid, if_sid,
4066                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4067         if (err)
4068                 return err;
4069
4070         err = sel_netnode_sid(addrp, family, &node_sid);
4071         if (err)
4072                 return err;
4073         return avc_has_perm(peer_sid, node_sid,
4074                             SECCLASS_NODE, NODE__RECVFROM, ad);
4075 }
4076
4077 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4078                                        u16 family)
4079 {
4080         int err = 0;
4081         struct sk_security_struct *sksec = sk->sk_security;
4082         u32 sk_sid = sksec->sid;
4083         struct common_audit_data ad;
4084         char *addrp;
4085
4086         COMMON_AUDIT_DATA_INIT(&ad, NET);
4087         ad.u.net.netif = skb->skb_iif;
4088         ad.u.net.family = family;
4089         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4090         if (err)
4091                 return err;
4092
4093         if (selinux_secmark_enabled()) {
4094                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4095                                    PACKET__RECV, &ad);
4096                 if (err)
4097                         return err;
4098         }
4099
4100         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4101         if (err)
4102                 return err;
4103         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4104
4105         return err;
4106 }
4107
4108 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4109 {
4110         int err;
4111         struct sk_security_struct *sksec = sk->sk_security;
4112         u16 family = sk->sk_family;
4113         u32 sk_sid = sksec->sid;
4114         struct common_audit_data ad;
4115         char *addrp;
4116         u8 secmark_active;
4117         u8 peerlbl_active;
4118
4119         if (family != PF_INET && family != PF_INET6)
4120                 return 0;
4121
4122         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4123         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4124                 family = PF_INET;
4125
4126         /* If any sort of compatibility mode is enabled then handoff processing
4127          * to the selinux_sock_rcv_skb_compat() function to deal with the
4128          * special handling.  We do this in an attempt to keep this function
4129          * as fast and as clean as possible. */
4130         if (!selinux_policycap_netpeer)
4131                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4132
4133         secmark_active = selinux_secmark_enabled();
4134         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4135         if (!secmark_active && !peerlbl_active)
4136                 return 0;
4137
4138         COMMON_AUDIT_DATA_INIT(&ad, NET);
4139         ad.u.net.netif = skb->skb_iif;
4140         ad.u.net.family = family;
4141         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4142         if (err)
4143                 return err;
4144
4145         if (peerlbl_active) {
4146                 u32 peer_sid;
4147
4148                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4149                 if (err)
4150                         return err;
4151                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4152                                                peer_sid, &ad);
4153                 if (err) {
4154                         selinux_netlbl_err(skb, err, 0);
4155                         return err;
4156                 }
4157                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4158                                    PEER__RECV, &ad);
4159                 if (err)
4160                         selinux_netlbl_err(skb, err, 0);
4161         }
4162
4163         if (secmark_active) {
4164                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4165                                    PACKET__RECV, &ad);
4166                 if (err)
4167                         return err;
4168         }
4169
4170         return err;
4171 }
4172
4173 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4174                                             int __user *optlen, unsigned len)
4175 {
4176         int err = 0;
4177         char *scontext;
4178         u32 scontext_len;
4179         struct sk_security_struct *sksec = sock->sk->sk_security;
4180         u32 peer_sid = SECSID_NULL;
4181
4182         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4183             sksec->sclass == SECCLASS_TCP_SOCKET)
4184                 peer_sid = sksec->peer_sid;
4185         if (peer_sid == SECSID_NULL)
4186                 return -ENOPROTOOPT;
4187
4188         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4189         if (err)
4190                 return err;
4191
4192         if (scontext_len > len) {
4193                 err = -ERANGE;
4194                 goto out_len;
4195         }
4196
4197         if (copy_to_user(optval, scontext, scontext_len))
4198                 err = -EFAULT;
4199
4200 out_len:
4201         if (put_user(scontext_len, optlen))
4202                 err = -EFAULT;
4203         kfree(scontext);
4204         return err;
4205 }
4206
4207 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4208 {
4209         u32 peer_secid = SECSID_NULL;
4210         u16 family;
4211
4212         if (skb && skb->protocol == htons(ETH_P_IP))
4213                 family = PF_INET;
4214         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4215                 family = PF_INET6;
4216         else if (sock)
4217                 family = sock->sk->sk_family;
4218         else
4219                 goto out;
4220
4221         if (sock && family == PF_UNIX)
4222                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4223         else if (skb)
4224                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4225
4226 out:
4227         *secid = peer_secid;
4228         if (peer_secid == SECSID_NULL)
4229                 return -EINVAL;
4230         return 0;
4231 }
4232
4233 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4234 {
4235         struct sk_security_struct *sksec;
4236
4237         sksec = kzalloc(sizeof(*sksec), priority);
4238         if (!sksec)
4239                 return -ENOMEM;
4240
4241         sksec->peer_sid = SECINITSID_UNLABELED;
4242         sksec->sid = SECINITSID_UNLABELED;
4243         selinux_netlbl_sk_security_reset(sksec);
4244         sk->sk_security = sksec;
4245
4246         return 0;
4247 }
4248
4249 static void selinux_sk_free_security(struct sock *sk)
4250 {
4251         struct sk_security_struct *sksec = sk->sk_security;
4252
4253         sk->sk_security = NULL;
4254         selinux_netlbl_sk_security_free(sksec);
4255         kfree(sksec);
4256 }
4257
4258 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4259 {
4260         struct sk_security_struct *sksec = sk->sk_security;
4261         struct sk_security_struct *newsksec = newsk->sk_security;
4262
4263         newsksec->sid = sksec->sid;
4264         newsksec->peer_sid = sksec->peer_sid;
4265         newsksec->sclass = sksec->sclass;
4266
4267         selinux_netlbl_sk_security_reset(newsksec);
4268 }
4269
4270 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4271 {
4272         if (!sk)
4273                 *secid = SECINITSID_ANY_SOCKET;
4274         else {
4275                 struct sk_security_struct *sksec = sk->sk_security;
4276
4277                 *secid = sksec->sid;
4278         }
4279 }
4280
4281 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4282 {
4283         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4284         struct sk_security_struct *sksec = sk->sk_security;
4285
4286         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4287             sk->sk_family == PF_UNIX)
4288                 isec->sid = sksec->sid;
4289         sksec->sclass = isec->sclass;
4290 }
4291
4292 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4293                                      struct request_sock *req)
4294 {
4295         struct sk_security_struct *sksec = sk->sk_security;
4296         int err;
4297         u16 family = sk->sk_family;
4298         u32 newsid;
4299         u32 peersid;
4300
4301         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4302         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4303                 family = PF_INET;
4304
4305         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4306         if (err)
4307                 return err;
4308         if (peersid == SECSID_NULL) {
4309                 req->secid = sksec->sid;
4310                 req->peer_secid = SECSID_NULL;
4311         } else {
4312                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4313                 if (err)
4314                         return err;
4315                 req->secid = newsid;
4316                 req->peer_secid = peersid;
4317         }
4318
4319         return selinux_netlbl_inet_conn_request(req, family);
4320 }
4321
4322 static void selinux_inet_csk_clone(struct sock *newsk,
4323                                    const struct request_sock *req)
4324 {
4325         struct sk_security_struct *newsksec = newsk->sk_security;
4326
4327         newsksec->sid = req->secid;
4328         newsksec->peer_sid = req->peer_secid;
4329         /* NOTE: Ideally, we should also get the isec->sid for the
4330            new socket in sync, but we don't have the isec available yet.
4331            So we will wait until sock_graft to do it, by which
4332            time it will have been created and available. */
4333
4334         /* We don't need to take any sort of lock here as we are the only
4335          * thread with access to newsksec */
4336         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4337 }
4338
4339 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4340 {
4341         u16 family = sk->sk_family;
4342         struct sk_security_struct *sksec = sk->sk_security;
4343
4344         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4345         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4346                 family = PF_INET;
4347
4348         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4349 }
4350
4351 static int selinux_secmark_relabel_packet(u32 sid)
4352 {
4353         const struct task_security_struct *__tsec;
4354         u32 tsid;
4355
4356         __tsec = current_security();
4357         tsid = __tsec->sid;
4358
4359         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4360 }
4361
4362 static void selinux_secmark_refcount_inc(void)
4363 {
4364         atomic_inc(&selinux_secmark_refcount);
4365 }
4366
4367 static void selinux_secmark_refcount_dec(void)
4368 {
4369         atomic_dec(&selinux_secmark_refcount);
4370 }
4371
4372 static void selinux_req_classify_flow(const struct request_sock *req,
4373                                       struct flowi *fl)
4374 {
4375         fl->flowi_secid = req->secid;
4376 }
4377
4378 static int selinux_tun_dev_create(void)
4379 {
4380         u32 sid = current_sid();
4381
4382         /* we aren't taking into account the "sockcreate" SID since the socket
4383          * that is being created here is not a socket in the traditional sense,
4384          * instead it is a private sock, accessible only to the kernel, and
4385          * representing a wide range of network traffic spanning multiple
4386          * connections unlike traditional sockets - check the TUN driver to
4387          * get a better understanding of why this socket is special */
4388
4389         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4390                             NULL);
4391 }
4392
4393 static void selinux_tun_dev_post_create(struct sock *sk)
4394 {
4395         struct sk_security_struct *sksec = sk->sk_security;
4396
4397         /* we don't currently perform any NetLabel based labeling here and it
4398          * isn't clear that we would want to do so anyway; while we could apply
4399          * labeling without the support of the TUN user the resulting labeled
4400          * traffic from the other end of the connection would almost certainly
4401          * cause confusion to the TUN user that had no idea network labeling
4402          * protocols were being used */
4403
4404         /* see the comments in selinux_tun_dev_create() about why we don't use
4405          * the sockcreate SID here */
4406
4407         sksec->sid = current_sid();
4408         sksec->sclass = SECCLASS_TUN_SOCKET;
4409 }
4410
4411 static int selinux_tun_dev_attach(struct sock *sk)
4412 {
4413         struct sk_security_struct *sksec = sk->sk_security;
4414         u32 sid = current_sid();
4415         int err;
4416
4417         err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4418                            TUN_SOCKET__RELABELFROM, NULL);
4419         if (err)
4420                 return err;
4421         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4422                            TUN_SOCKET__RELABELTO, NULL);
4423         if (err)
4424                 return err;
4425
4426         sksec->sid = sid;
4427
4428         return 0;
4429 }
4430
4431 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4432 {
4433         int err = 0;
4434         u32 perm;
4435         struct nlmsghdr *nlh;
4436         struct sk_security_struct *sksec = sk->sk_security;
4437
4438         if (skb->len < NLMSG_SPACE(0)) {
4439                 err = -EINVAL;
4440                 goto out;
4441         }
4442         nlh = nlmsg_hdr(skb);
4443
4444         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4445         if (err) {
4446                 if (err == -EINVAL) {
4447                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4448                                   "SELinux:  unrecognized netlink message"
4449                                   " type=%hu for sclass=%hu\n",
4450                                   nlh->nlmsg_type, sksec->sclass);
4451                         if (!selinux_enforcing || security_get_allow_unknown())
4452                                 err = 0;
4453                 }
4454
4455                 /* Ignore */
4456                 if (err == -ENOENT)
4457                         err = 0;
4458                 goto out;
4459         }
4460
4461         err = sock_has_perm(current, sk, perm);
4462 out:
4463         return err;
4464 }
4465
4466 #ifdef CONFIG_NETFILTER
4467
4468 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4469                                        u16 family)
4470 {
4471         int err;
4472         char *addrp;
4473         u32 peer_sid;
4474         struct common_audit_data ad;
4475         u8 secmark_active;
4476         u8 netlbl_active;
4477         u8 peerlbl_active;
4478
4479         if (!selinux_policycap_netpeer)
4480                 return NF_ACCEPT;
4481
4482         secmark_active = selinux_secmark_enabled();
4483         netlbl_active = netlbl_enabled();
4484         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4485         if (!secmark_active && !peerlbl_active)
4486                 return NF_ACCEPT;
4487
4488         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4489                 return NF_DROP;
4490
4491         COMMON_AUDIT_DATA_INIT(&ad, NET);
4492         ad.u.net.netif = ifindex;
4493         ad.u.net.family = family;
4494         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4495                 return NF_DROP;
4496
4497         if (peerlbl_active) {
4498                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4499                                                peer_sid, &ad);
4500                 if (err) {
4501                         selinux_netlbl_err(skb, err, 1);
4502                         return NF_DROP;
4503                 }
4504         }
4505
4506         if (secmark_active)
4507                 if (avc_has_perm(peer_sid, skb->secmark,
4508                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4509                         return NF_DROP;
4510
4511         if (netlbl_active)
4512                 /* we do this in the FORWARD path and not the POST_ROUTING
4513                  * path because we want to make sure we apply the necessary
4514                  * labeling before IPsec is applied so we can leverage AH
4515                  * protection */
4516                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4517                         return NF_DROP;
4518
4519         return NF_ACCEPT;
4520 }
4521
4522 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4523                                          struct sk_buff *skb,
4524                                          const struct net_device *in,
4525                                          const struct net_device *out,
4526                                          int (*okfn)(struct sk_buff *))
4527 {
4528         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4529 }
4530
4531 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4532 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4533                                          struct sk_buff *skb,
4534                                          const struct net_device *in,
4535                                          const struct net_device *out,
4536                                          int (*okfn)(struct sk_buff *))
4537 {
4538         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4539 }
4540 #endif  /* IPV6 */
4541
4542 static unsigned int selinux_ip_output(struct sk_buff *skb,
4543                                       u16 family)
4544 {
4545         u32 sid;
4546
4547         if (!netlbl_enabled())
4548                 return NF_ACCEPT;
4549
4550         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4551          * because we want to make sure we apply the necessary labeling
4552          * before IPsec is applied so we can leverage AH protection */
4553         if (skb->sk) {
4554                 struct sk_security_struct *sksec = skb->sk->sk_security;
4555                 sid = sksec->sid;
4556         } else
4557                 sid = SECINITSID_KERNEL;
4558         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4559                 return NF_DROP;
4560
4561         return NF_ACCEPT;
4562 }
4563
4564 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4565                                         struct sk_buff *skb,
4566                                         const struct net_device *in,
4567                                         const struct net_device *out,
4568                                         int (*okfn)(struct sk_buff *))
4569 {
4570         return selinux_ip_output(skb, PF_INET);
4571 }
4572
4573 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4574                                                 int ifindex,
4575                                                 u16 family)
4576 {
4577         struct sock *sk = skb->sk;
4578         struct sk_security_struct *sksec;
4579         struct common_audit_data ad;
4580         char *addrp;
4581         u8 proto;
4582
4583         if (sk == NULL)
4584                 return NF_ACCEPT;
4585         sksec = sk->sk_security;
4586
4587         COMMON_AUDIT_DATA_INIT(&ad, NET);
4588         ad.u.net.netif = ifindex;
4589         ad.u.net.family = family;
4590         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4591                 return NF_DROP;
4592
4593         if (selinux_secmark_enabled())
4594                 if (avc_has_perm(sksec->sid, skb->secmark,
4595                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4596                         return NF_DROP_ERR(-ECONNREFUSED);
4597
4598         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4599                 return NF_DROP_ERR(-ECONNREFUSED);
4600
4601         return NF_ACCEPT;
4602 }
4603
4604 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4605                                          u16 family)
4606 {
4607         u32 secmark_perm;
4608         u32 peer_sid;
4609         struct sock *sk;
4610         struct common_audit_data ad;
4611         char *addrp;
4612         u8 secmark_active;
4613         u8 peerlbl_active;
4614
4615         /* If any sort of compatibility mode is enabled then handoff processing
4616          * to the selinux_ip_postroute_compat() function to deal with the
4617          * special handling.  We do this in an attempt to keep this function
4618          * as fast and as clean as possible. */
4619         if (!selinux_policycap_netpeer)
4620                 return selinux_ip_postroute_compat(skb, ifindex, family);
4621 #ifdef CONFIG_XFRM
4622         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4623          * packet transformation so allow the packet to pass without any checks
4624          * since we'll have another chance to perform access control checks
4625          * when the packet is on it's final way out.
4626          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4627          *       is NULL, in this case go ahead and apply access control. */
4628         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4629                 return NF_ACCEPT;
4630 #endif
4631         secmark_active = selinux_secmark_enabled();
4632         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4633         if (!secmark_active && !peerlbl_active)
4634                 return NF_ACCEPT;
4635
4636         /* if the packet is being forwarded then get the peer label from the
4637          * packet itself; otherwise check to see if it is from a local
4638          * application or the kernel, if from an application get the peer label
4639          * from the sending socket, otherwise use the kernel's sid */
4640         sk = skb->sk;
4641         if (sk == NULL) {
4642                 if (skb->skb_iif) {
4643                         secmark_perm = PACKET__FORWARD_OUT;
4644                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4645                                 return NF_DROP;
4646                 } else {
4647                         secmark_perm = PACKET__SEND;
4648                         peer_sid = SECINITSID_KERNEL;
4649                 }
4650         } else {
4651                 struct sk_security_struct *sksec = sk->sk_security;
4652                 peer_sid = sksec->sid;
4653                 secmark_perm = PACKET__SEND;
4654         }
4655
4656         COMMON_AUDIT_DATA_INIT(&ad, NET);
4657         ad.u.net.netif = ifindex;
4658         ad.u.net.family = family;
4659         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4660                 return NF_DROP;
4661
4662         if (secmark_active)
4663                 if (avc_has_perm(peer_sid, skb->secmark,
4664                                  SECCLASS_PACKET, secmark_perm, &ad))
4665                         return NF_DROP_ERR(-ECONNREFUSED);
4666
4667         if (peerlbl_active) {
4668                 u32 if_sid;
4669                 u32 node_sid;
4670
4671                 if (sel_netif_sid(ifindex, &if_sid))
4672                         return NF_DROP;
4673                 if (avc_has_perm(peer_sid, if_sid,
4674                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4675                         return NF_DROP_ERR(-ECONNREFUSED);
4676
4677                 if (sel_netnode_sid(addrp, family, &node_sid))
4678                         return NF_DROP;
4679                 if (avc_has_perm(peer_sid, node_sid,
4680                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4681                         return NF_DROP_ERR(-ECONNREFUSED);
4682         }
4683
4684         return NF_ACCEPT;
4685 }
4686
4687 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4688                                            struct sk_buff *skb,
4689                                            const struct net_device *in,
4690                                            const struct net_device *out,
4691                                            int (*okfn)(struct sk_buff *))
4692 {
4693         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4694 }
4695
4696 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4697 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4698                                            struct sk_buff *skb,
4699                                            const struct net_device *in,
4700                                            const struct net_device *out,
4701                                            int (*okfn)(struct sk_buff *))
4702 {
4703         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4704 }
4705 #endif  /* IPV6 */
4706
4707 #endif  /* CONFIG_NETFILTER */
4708
4709 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4710 {
4711         int err;
4712
4713         err = cap_netlink_send(sk, skb);
4714         if (err)
4715                 return err;
4716
4717         return selinux_nlmsg_perm(sk, skb);
4718 }
4719
4720 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4721 {
4722         int err;
4723         struct common_audit_data ad;
4724         u32 sid;
4725
4726         err = cap_netlink_recv(skb, capability);
4727         if (err)
4728                 return err;
4729
4730         COMMON_AUDIT_DATA_INIT(&ad, CAP);
4731         ad.u.cap = capability;
4732
4733         security_task_getsecid(current, &sid);
4734         return avc_has_perm(sid, sid, SECCLASS_CAPABILITY,
4735                             CAP_TO_MASK(capability), &ad);
4736 }
4737
4738 static int ipc_alloc_security(struct task_struct *task,
4739                               struct kern_ipc_perm *perm,
4740                               u16 sclass)
4741 {
4742         struct ipc_security_struct *isec;
4743         u32 sid;
4744
4745         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4746         if (!isec)
4747                 return -ENOMEM;
4748
4749         sid = task_sid(task);
4750         isec->sclass = sclass;
4751         isec->sid = sid;
4752         perm->security = isec;
4753
4754         return 0;
4755 }
4756
4757 static void ipc_free_security(struct kern_ipc_perm *perm)
4758 {
4759         struct ipc_security_struct *isec = perm->security;
4760         perm->security = NULL;
4761         kfree(isec);
4762 }
4763
4764 static int msg_msg_alloc_security(struct msg_msg *msg)
4765 {
4766         struct msg_security_struct *msec;
4767
4768         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4769         if (!msec)
4770                 return -ENOMEM;
4771
4772         msec->sid = SECINITSID_UNLABELED;
4773         msg->security = msec;
4774
4775         return 0;
4776 }
4777
4778 static void msg_msg_free_security(struct msg_msg *msg)
4779 {
4780         struct msg_security_struct *msec = msg->security;
4781
4782         msg->security = NULL;
4783         kfree(msec);
4784 }
4785
4786 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4787                         u32 perms)
4788 {
4789         struct ipc_security_struct *isec;
4790         struct common_audit_data ad;
4791         u32 sid = current_sid();
4792
4793         isec = ipc_perms->security;
4794
4795         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4796         ad.u.ipc_id = ipc_perms->key;
4797
4798         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4799 }
4800
4801 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4802 {
4803         return msg_msg_alloc_security(msg);
4804 }
4805
4806 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4807 {
4808         msg_msg_free_security(msg);
4809 }
4810
4811 /* message queue security operations */
4812 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4813 {
4814         struct ipc_security_struct *isec;
4815         struct common_audit_data ad;
4816         u32 sid = current_sid();
4817         int rc;
4818
4819         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4820         if (rc)
4821                 return rc;
4822
4823         isec = msq->q_perm.security;
4824
4825         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4826         ad.u.ipc_id = msq->q_perm.key;
4827
4828         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4829                           MSGQ__CREATE, &ad);
4830         if (rc) {
4831                 ipc_free_security(&msq->q_perm);
4832                 return rc;
4833         }
4834         return 0;
4835 }
4836
4837 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4838 {
4839         ipc_free_security(&msq->q_perm);
4840 }
4841
4842 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4843 {
4844         struct ipc_security_struct *isec;
4845         struct common_audit_data ad;
4846         u32 sid = current_sid();
4847
4848         isec = msq->q_perm.security;
4849
4850         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4851         ad.u.ipc_id = msq->q_perm.key;
4852
4853         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4854                             MSGQ__ASSOCIATE, &ad);
4855 }
4856
4857 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4858 {
4859         int err;
4860         int perms;
4861
4862         switch (cmd) {
4863         case IPC_INFO:
4864         case MSG_INFO:
4865                 /* No specific object, just general system-wide information. */
4866                 return task_has_system(current, SYSTEM__IPC_INFO);
4867         case IPC_STAT:
4868         case MSG_STAT:
4869                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4870                 break;
4871         case IPC_SET:
4872                 perms = MSGQ__SETATTR;
4873                 break;
4874         case IPC_RMID:
4875                 perms = MSGQ__DESTROY;
4876                 break;
4877         default:
4878                 return 0;
4879         }
4880
4881         err = ipc_has_perm(&msq->q_perm, perms);
4882         return err;
4883 }
4884
4885 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4886 {
4887         struct ipc_security_struct *isec;
4888         struct msg_security_struct *msec;
4889         struct common_audit_data ad;
4890         u32 sid = current_sid();
4891         int rc;
4892
4893         isec = msq->q_perm.security;
4894         msec = msg->security;
4895
4896         /*
4897          * First time through, need to assign label to the message
4898          */
4899         if (msec->sid == SECINITSID_UNLABELED) {
4900                 /*
4901                  * Compute new sid based on current process and
4902                  * message queue this message will be stored in
4903                  */
4904                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4905                                              NULL, &msec->sid);
4906                 if (rc)
4907                         return rc;
4908         }
4909
4910         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4911         ad.u.ipc_id = msq->q_perm.key;
4912
4913         /* Can this process write to the queue? */
4914         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4915                           MSGQ__WRITE, &ad);
4916         if (!rc)
4917                 /* Can this process send the message */
4918                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4919                                   MSG__SEND, &ad);
4920         if (!rc)
4921                 /* Can the message be put in the queue? */
4922                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4923                                   MSGQ__ENQUEUE, &ad);
4924
4925         return rc;
4926 }
4927
4928 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4929                                     struct task_struct *target,
4930                                     long type, int mode)
4931 {
4932         struct ipc_security_struct *isec;
4933         struct msg_security_struct *msec;
4934         struct common_audit_data ad;
4935         u32 sid = task_sid(target);
4936         int rc;
4937
4938         isec = msq->q_perm.security;
4939         msec = msg->security;
4940
4941         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4942         ad.u.ipc_id = msq->q_perm.key;
4943
4944         rc = avc_has_perm(sid, isec->sid,
4945                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4946         if (!rc)
4947                 rc = avc_has_perm(sid, msec->sid,
4948                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4949         return rc;
4950 }
4951
4952 /* Shared Memory security operations */
4953 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4954 {
4955         struct ipc_security_struct *isec;
4956         struct common_audit_data ad;
4957         u32 sid = current_sid();
4958         int rc;
4959
4960         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4961         if (rc)
4962                 return rc;
4963
4964         isec = shp->shm_perm.security;
4965
4966         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4967         ad.u.ipc_id = shp->shm_perm.key;
4968
4969         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4970                           SHM__CREATE, &ad);
4971         if (rc) {
4972                 ipc_free_security(&shp->shm_perm);
4973                 return rc;
4974         }
4975         return 0;
4976 }
4977
4978 static void selinux_shm_free_security(struct shmid_kernel *shp)
4979 {
4980         ipc_free_security(&shp->shm_perm);
4981 }
4982
4983 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4984 {
4985         struct ipc_security_struct *isec;
4986         struct common_audit_data ad;
4987         u32 sid = current_sid();
4988
4989         isec = shp->shm_perm.security;
4990
4991         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4992         ad.u.ipc_id = shp->shm_perm.key;
4993
4994         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4995                             SHM__ASSOCIATE, &ad);
4996 }
4997
4998 /* Note, at this point, shp is locked down */
4999 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5000 {
5001         int perms;
5002         int err;
5003
5004         switch (cmd) {
5005         case IPC_INFO:
5006         case SHM_INFO:
5007                 /* No specific object, just general system-wide information. */
5008                 return task_has_system(current, SYSTEM__IPC_INFO);
5009         case IPC_STAT:
5010         case SHM_STAT:
5011                 perms = SHM__GETATTR | SHM__ASSOCIATE;
5012                 break;
5013         case IPC_SET:
5014                 perms = SHM__SETATTR;
5015                 break;
5016         case SHM_LOCK:
5017         case SHM_UNLOCK:
5018                 perms = SHM__LOCK;
5019                 break;
5020         case IPC_RMID:
5021                 perms = SHM__DESTROY;
5022                 break;
5023         default:
5024                 return 0;
5025         }
5026
5027         err = ipc_has_perm(&shp->shm_perm, perms);
5028         return err;
5029 }
5030
5031 static int selinux_shm_shmat(struct shmid_kernel *shp,
5032                              char __user *shmaddr, int shmflg)
5033 {
5034         u32 perms;
5035
5036         if (shmflg & SHM_RDONLY)
5037                 perms = SHM__READ;
5038         else
5039                 perms = SHM__READ | SHM__WRITE;
5040
5041         return ipc_has_perm(&shp->shm_perm, perms);
5042 }
5043
5044 /* Semaphore security operations */
5045 static int selinux_sem_alloc_security(struct sem_array *sma)
5046 {
5047         struct ipc_security_struct *isec;
5048         struct common_audit_data ad;
5049         u32 sid = current_sid();
5050         int rc;
5051
5052         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5053         if (rc)
5054                 return rc;
5055
5056         isec = sma->sem_perm.security;
5057
5058         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5059         ad.u.ipc_id = sma->sem_perm.key;
5060
5061         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5062                           SEM__CREATE, &ad);
5063         if (rc) {
5064                 ipc_free_security(&sma->sem_perm);
5065                 return rc;
5066         }
5067         return 0;
5068 }
5069
5070 static void selinux_sem_free_security(struct sem_array *sma)
5071 {
5072         ipc_free_security(&sma->sem_perm);
5073 }
5074
5075 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5076 {
5077         struct ipc_security_struct *isec;
5078         struct common_audit_data ad;
5079         u32 sid = current_sid();
5080
5081         isec = sma->sem_perm.security;
5082
5083         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5084         ad.u.ipc_id = sma->sem_perm.key;
5085
5086         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5087                             SEM__ASSOCIATE, &ad);
5088 }
5089
5090 /* Note, at this point, sma is locked down */
5091 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5092 {
5093         int err;
5094         u32 perms;
5095
5096         switch (cmd) {
5097         case IPC_INFO:
5098         case SEM_INFO:
5099                 /* No specific object, just general system-wide information. */
5100                 return task_has_system(current, SYSTEM__IPC_INFO);
5101         case GETPID:
5102         case GETNCNT:
5103         case GETZCNT:
5104                 perms = SEM__GETATTR;
5105                 break;
5106         case GETVAL:
5107         case GETALL:
5108                 perms = SEM__READ;
5109                 break;
5110         case SETVAL:
5111         case SETALL:
5112                 perms = SEM__WRITE;
5113                 break;
5114         case IPC_RMID:
5115                 perms = SEM__DESTROY;
5116                 break;
5117         case IPC_SET:
5118                 perms = SEM__SETATTR;
5119                 break;
5120         case IPC_STAT:
5121         case SEM_STAT:
5122                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5123                 break;
5124         default:
5125                 return 0;
5126         }
5127
5128         err = ipc_has_perm(&sma->sem_perm, perms);
5129         return err;
5130 }
5131
5132 static int selinux_sem_semop(struct sem_array *sma,
5133                              struct sembuf *sops, unsigned nsops, int alter)
5134 {
5135         u32 perms;
5136
5137         if (alter)
5138                 perms = SEM__READ | SEM__WRITE;
5139         else
5140                 perms = SEM__READ;
5141
5142         return ipc_has_perm(&sma->sem_perm, perms);
5143 }
5144
5145 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5146 {
5147         u32 av = 0;
5148
5149         av = 0;
5150         if (flag & S_IRUGO)
5151                 av |= IPC__UNIX_READ;
5152         if (flag & S_IWUGO)
5153                 av |= IPC__UNIX_WRITE;
5154
5155         if (av == 0)
5156                 return 0;
5157
5158         return ipc_has_perm(ipcp, av);
5159 }
5160
5161 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5162 {
5163         struct ipc_security_struct *isec = ipcp->security;
5164         *secid = isec->sid;
5165 }
5166
5167 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5168 {
5169         if (inode)
5170                 inode_doinit_with_dentry(inode, dentry);
5171 }
5172
5173 static int selinux_getprocattr(struct task_struct *p,
5174                                char *name, char **value)
5175 {
5176         const struct task_security_struct *__tsec;
5177         u32 sid;
5178         int error;
5179         unsigned len;
5180
5181         if (current != p) {
5182                 error = current_has_perm(p, PROCESS__GETATTR);
5183                 if (error)
5184                         return error;
5185         }
5186
5187         rcu_read_lock();
5188         __tsec = __task_cred(p)->security;
5189
5190         if (!strcmp(name, "current"))
5191                 sid = __tsec->sid;
5192         else if (!strcmp(name, "prev"))
5193                 sid = __tsec->osid;
5194         else if (!strcmp(name, "exec"))
5195                 sid = __tsec->exec_sid;
5196         else if (!strcmp(name, "fscreate"))
5197                 sid = __tsec->create_sid;
5198         else if (!strcmp(name, "keycreate"))
5199                 sid = __tsec->keycreate_sid;
5200         else if (!strcmp(name, "sockcreate"))
5201                 sid = __tsec->sockcreate_sid;
5202         else
5203                 goto invalid;
5204         rcu_read_unlock();
5205
5206         if (!sid)
5207                 return 0;
5208
5209         error = security_sid_to_context(sid, value, &len);
5210         if (error)
5211                 return error;
5212         return len;
5213
5214 invalid:
5215         rcu_read_unlock();
5216         return -EINVAL;
5217 }
5218
5219 static int selinux_setprocattr(struct task_struct *p,
5220                                char *name, void *value, size_t size)
5221 {
5222         struct task_security_struct *tsec;
5223         struct task_struct *tracer;
5224         struct cred *new;
5225         u32 sid = 0, ptsid;
5226         int error;
5227         char *str = value;
5228
5229         if (current != p) {
5230                 /* SELinux only allows a process to change its own
5231                    security attributes. */
5232                 return -EACCES;
5233         }
5234
5235         /*
5236          * Basic control over ability to set these attributes at all.
5237          * current == p, but we'll pass them separately in case the
5238          * above restriction is ever removed.
5239          */
5240         if (!strcmp(name, "exec"))
5241                 error = current_has_perm(p, PROCESS__SETEXEC);
5242         else if (!strcmp(name, "fscreate"))
5243                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5244         else if (!strcmp(name, "keycreate"))
5245                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5246         else if (!strcmp(name, "sockcreate"))
5247                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5248         else if (!strcmp(name, "current"))
5249                 error = current_has_perm(p, PROCESS__SETCURRENT);
5250         else
5251                 error = -EINVAL;
5252         if (error)
5253                 return error;
5254
5255         /* Obtain a SID for the context, if one was specified. */
5256         if (size && str[1] && str[1] != '\n') {
5257                 if (str[size-1] == '\n') {
5258                         str[size-1] = 0;
5259                         size--;
5260                 }
5261                 error = security_context_to_sid(value, size, &sid);
5262                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5263                         if (!capable(CAP_MAC_ADMIN))
5264                                 return error;
5265                         error = security_context_to_sid_force(value, size,
5266                                                               &sid);
5267                 }
5268                 if (error)
5269                         return error;
5270         }
5271
5272         new = prepare_creds();
5273         if (!new)
5274                 return -ENOMEM;
5275
5276         /* Permission checking based on the specified context is
5277            performed during the actual operation (execve,
5278            open/mkdir/...), when we know the full context of the
5279            operation.  See selinux_bprm_set_creds for the execve
5280            checks and may_create for the file creation checks. The
5281            operation will then fail if the context is not permitted. */
5282         tsec = new->security;
5283         if (!strcmp(name, "exec")) {
5284                 tsec->exec_sid = sid;
5285         } else if (!strcmp(name, "fscreate")) {
5286                 tsec->create_sid = sid;
5287         } else if (!strcmp(name, "keycreate")) {
5288                 error = may_create_key(sid, p);
5289                 if (error)
5290                         goto abort_change;
5291                 tsec->keycreate_sid = sid;
5292         } else if (!strcmp(name, "sockcreate")) {
5293                 tsec->sockcreate_sid = sid;
5294         } else if (!strcmp(name, "current")) {
5295                 error = -EINVAL;
5296                 if (sid == 0)
5297                         goto abort_change;
5298
5299                 /* Only allow single threaded processes to change context */
5300                 error = -EPERM;
5301                 if (!current_is_single_threaded()) {
5302                         error = security_bounded_transition(tsec->sid, sid);
5303                         if (error)
5304                                 goto abort_change;
5305                 }
5306
5307                 /* Check permissions for the transition. */
5308                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5309                                      PROCESS__DYNTRANSITION, NULL);
5310                 if (error)
5311                         goto abort_change;
5312
5313                 /* Check for ptracing, and update the task SID if ok.
5314                    Otherwise, leave SID unchanged and fail. */
5315                 ptsid = 0;
5316                 task_lock(p);
5317                 tracer = ptrace_parent(p);
5318                 if (tracer)
5319                         ptsid = task_sid(tracer);
5320                 task_unlock(p);
5321
5322                 if (tracer) {
5323                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5324                                              PROCESS__PTRACE, NULL);
5325                         if (error)
5326                                 goto abort_change;
5327                 }
5328
5329                 tsec->sid = sid;
5330         } else {
5331                 error = -EINVAL;
5332                 goto abort_change;
5333         }
5334
5335         commit_creds(new);
5336         return size;
5337
5338 abort_change:
5339         abort_creds(new);
5340         return error;
5341 }
5342
5343 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5344 {
5345         return security_sid_to_context(secid, secdata, seclen);
5346 }
5347
5348 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5349 {
5350         return security_context_to_sid(secdata, seclen, secid);
5351 }
5352
5353 static void selinux_release_secctx(char *secdata, u32 seclen)
5354 {
5355         kfree(secdata);
5356 }
5357
5358 /*
5359  *      called with inode->i_mutex locked
5360  */
5361 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5362 {
5363         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5364 }
5365
5366 /*
5367  *      called with inode->i_mutex locked
5368  */
5369 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5370 {
5371         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5372 }
5373
5374 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5375 {
5376         int len = 0;
5377         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5378                                                 ctx, true);
5379         if (len < 0)
5380                 return len;
5381         *ctxlen = len;
5382         return 0;
5383 }
5384 #ifdef CONFIG_KEYS
5385
5386 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5387                              unsigned long flags)
5388 {
5389         const struct task_security_struct *tsec;
5390         struct key_security_struct *ksec;
5391
5392         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5393         if (!ksec)
5394                 return -ENOMEM;
5395
5396         tsec = cred->security;
5397         if (tsec->keycreate_sid)
5398                 ksec->sid = tsec->keycreate_sid;
5399         else
5400                 ksec->sid = tsec->sid;
5401
5402         k->security = ksec;
5403         return 0;
5404 }
5405
5406 static void selinux_key_free(struct key *k)
5407 {
5408         struct key_security_struct *ksec = k->security;
5409
5410         k->security = NULL;
5411         kfree(ksec);
5412 }
5413
5414 static int selinux_key_permission(key_ref_t key_ref,
5415                                   const struct cred *cred,
5416                                   key_perm_t perm)
5417 {
5418         struct key *key;
5419         struct key_security_struct *ksec;
5420         u32 sid;
5421
5422         /* if no specific permissions are requested, we skip the
5423            permission check. No serious, additional covert channels
5424            appear to be created. */
5425         if (perm == 0)
5426                 return 0;
5427
5428         sid = cred_sid(cred);
5429
5430         key = key_ref_to_ptr(key_ref);
5431         ksec = key->security;
5432
5433         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5434 }
5435
5436 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5437 {
5438         struct key_security_struct *ksec = key->security;
5439         char *context = NULL;
5440         unsigned len;
5441         int rc;
5442
5443         rc = security_sid_to_context(ksec->sid, &context, &len);
5444         if (!rc)
5445                 rc = len;
5446         *_buffer = context;
5447         return rc;
5448 }
5449
5450 #endif
5451
5452 static struct security_operations selinux_ops = {
5453         .name =                         "selinux",
5454
5455         .ptrace_access_check =          selinux_ptrace_access_check,
5456         .ptrace_traceme =               selinux_ptrace_traceme,
5457         .capget =                       selinux_capget,
5458         .capset =                       selinux_capset,
5459         .capable =                      selinux_capable,
5460         .quotactl =                     selinux_quotactl,
5461         .quota_on =                     selinux_quota_on,
5462         .syslog =                       selinux_syslog,
5463         .vm_enough_memory =             selinux_vm_enough_memory,
5464
5465         .netlink_send =                 selinux_netlink_send,
5466         .netlink_recv =                 selinux_netlink_recv,
5467
5468         .bprm_set_creds =               selinux_bprm_set_creds,
5469         .bprm_committing_creds =        selinux_bprm_committing_creds,
5470         .bprm_committed_creds =         selinux_bprm_committed_creds,
5471         .bprm_secureexec =              selinux_bprm_secureexec,
5472
5473         .sb_alloc_security =            selinux_sb_alloc_security,
5474         .sb_free_security =             selinux_sb_free_security,
5475         .sb_copy_data =                 selinux_sb_copy_data,
5476         .sb_remount =                   selinux_sb_remount,
5477         .sb_kern_mount =                selinux_sb_kern_mount,
5478         .sb_show_options =              selinux_sb_show_options,
5479         .sb_statfs =                    selinux_sb_statfs,
5480         .sb_mount =                     selinux_mount,
5481         .sb_umount =                    selinux_umount,
5482         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5483         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5484         .sb_parse_opts_str =            selinux_parse_opts_str,
5485
5486
5487         .inode_alloc_security =         selinux_inode_alloc_security,
5488         .inode_free_security =          selinux_inode_free_security,
5489         .inode_init_security =          selinux_inode_init_security,
5490         .inode_create =                 selinux_inode_create,
5491         .inode_link =                   selinux_inode_link,
5492         .inode_unlink =                 selinux_inode_unlink,
5493         .inode_symlink =                selinux_inode_symlink,
5494         .inode_mkdir =                  selinux_inode_mkdir,
5495         .inode_rmdir =                  selinux_inode_rmdir,
5496         .inode_mknod =                  selinux_inode_mknod,
5497         .inode_rename =                 selinux_inode_rename,
5498         .inode_readlink =               selinux_inode_readlink,
5499         .inode_follow_link =            selinux_inode_follow_link,
5500         .inode_permission =             selinux_inode_permission,
5501         .inode_setattr =                selinux_inode_setattr,
5502         .inode_getattr =                selinux_inode_getattr,
5503         .inode_setxattr =               selinux_inode_setxattr,
5504         .inode_post_setxattr =          selinux_inode_post_setxattr,
5505         .inode_getxattr =               selinux_inode_getxattr,
5506         .inode_listxattr =              selinux_inode_listxattr,
5507         .inode_removexattr =            selinux_inode_removexattr,
5508         .inode_getsecurity =            selinux_inode_getsecurity,
5509         .inode_setsecurity =            selinux_inode_setsecurity,
5510         .inode_listsecurity =           selinux_inode_listsecurity,
5511         .inode_getsecid =               selinux_inode_getsecid,
5512
5513         .file_permission =              selinux_file_permission,
5514         .file_alloc_security =          selinux_file_alloc_security,
5515         .file_free_security =           selinux_file_free_security,
5516         .file_ioctl =                   selinux_file_ioctl,
5517         .file_mmap =                    selinux_file_mmap,
5518         .file_mprotect =                selinux_file_mprotect,
5519         .file_lock =                    selinux_file_lock,
5520         .file_fcntl =                   selinux_file_fcntl,
5521         .file_set_fowner =              selinux_file_set_fowner,
5522         .file_send_sigiotask =          selinux_file_send_sigiotask,
5523         .file_receive =                 selinux_file_receive,
5524
5525         .dentry_open =                  selinux_dentry_open,
5526
5527         .task_create =                  selinux_task_create,
5528         .cred_alloc_blank =             selinux_cred_alloc_blank,
5529         .cred_free =                    selinux_cred_free,
5530         .cred_prepare =                 selinux_cred_prepare,
5531         .cred_transfer =                selinux_cred_transfer,
5532         .kernel_act_as =                selinux_kernel_act_as,
5533         .kernel_create_files_as =       selinux_kernel_create_files_as,
5534         .kernel_module_request =        selinux_kernel_module_request,
5535         .task_setpgid =                 selinux_task_setpgid,
5536         .task_getpgid =                 selinux_task_getpgid,
5537         .task_getsid =                  selinux_task_getsid,
5538         .task_getsecid =                selinux_task_getsecid,
5539         .task_setnice =                 selinux_task_setnice,
5540         .task_setioprio =               selinux_task_setioprio,
5541         .task_getioprio =               selinux_task_getioprio,
5542         .task_setrlimit =               selinux_task_setrlimit,
5543         .task_setscheduler =            selinux_task_setscheduler,
5544         .task_getscheduler =            selinux_task_getscheduler,
5545         .task_movememory =              selinux_task_movememory,
5546         .task_kill =                    selinux_task_kill,
5547         .task_wait =                    selinux_task_wait,
5548         .task_to_inode =                selinux_task_to_inode,
5549
5550         .ipc_permission =               selinux_ipc_permission,
5551         .ipc_getsecid =                 selinux_ipc_getsecid,
5552
5553         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5554         .msg_msg_free_security =        selinux_msg_msg_free_security,
5555
5556         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5557         .msg_queue_free_security =      selinux_msg_queue_free_security,
5558         .msg_queue_associate =          selinux_msg_queue_associate,
5559         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5560         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5561         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5562
5563         .shm_alloc_security =           selinux_shm_alloc_security,
5564         .shm_free_security =            selinux_shm_free_security,
5565         .shm_associate =                selinux_shm_associate,
5566         .shm_shmctl =                   selinux_shm_shmctl,
5567         .shm_shmat =                    selinux_shm_shmat,
5568
5569         .sem_alloc_security =           selinux_sem_alloc_security,
5570         .sem_free_security =            selinux_sem_free_security,
5571         .sem_associate =                selinux_sem_associate,
5572         .sem_semctl =                   selinux_sem_semctl,
5573         .sem_semop =                    selinux_sem_semop,
5574
5575         .d_instantiate =                selinux_d_instantiate,
5576
5577         .getprocattr =                  selinux_getprocattr,
5578         .setprocattr =                  selinux_setprocattr,
5579
5580         .secid_to_secctx =              selinux_secid_to_secctx,
5581         .secctx_to_secid =              selinux_secctx_to_secid,
5582         .release_secctx =               selinux_release_secctx,
5583         .inode_notifysecctx =           selinux_inode_notifysecctx,
5584         .inode_setsecctx =              selinux_inode_setsecctx,
5585         .inode_getsecctx =              selinux_inode_getsecctx,
5586
5587         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5588         .unix_may_send =                selinux_socket_unix_may_send,
5589
5590         .socket_create =                selinux_socket_create,
5591         .socket_post_create =           selinux_socket_post_create,
5592         .socket_bind =                  selinux_socket_bind,
5593         .socket_connect =               selinux_socket_connect,
5594         .socket_listen =                selinux_socket_listen,
5595         .socket_accept =                selinux_socket_accept,
5596         .socket_sendmsg =               selinux_socket_sendmsg,
5597         .socket_recvmsg =               selinux_socket_recvmsg,
5598         .socket_getsockname =           selinux_socket_getsockname,
5599         .socket_getpeername =           selinux_socket_getpeername,
5600         .socket_getsockopt =            selinux_socket_getsockopt,
5601         .socket_setsockopt =            selinux_socket_setsockopt,
5602         .socket_shutdown =              selinux_socket_shutdown,
5603         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5604         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5605         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5606         .sk_alloc_security =            selinux_sk_alloc_security,
5607         .sk_free_security =             selinux_sk_free_security,
5608         .sk_clone_security =            selinux_sk_clone_security,
5609         .sk_getsecid =                  selinux_sk_getsecid,
5610         .sock_graft =                   selinux_sock_graft,
5611         .inet_conn_request =            selinux_inet_conn_request,
5612         .inet_csk_clone =               selinux_inet_csk_clone,
5613         .inet_conn_established =        selinux_inet_conn_established,
5614         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
5615         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
5616         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
5617         .req_classify_flow =            selinux_req_classify_flow,
5618         .tun_dev_create =               selinux_tun_dev_create,
5619         .tun_dev_post_create =          selinux_tun_dev_post_create,
5620         .tun_dev_attach =               selinux_tun_dev_attach,
5621
5622 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5623         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5624         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5625         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5626         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5627         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5628         .xfrm_state_free_security =     selinux_xfrm_state_free,
5629         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5630         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5631         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5632         .xfrm_decode_session =          selinux_xfrm_decode_session,
5633 #endif
5634
5635 #ifdef CONFIG_KEYS
5636         .key_alloc =                    selinux_key_alloc,
5637         .key_free =                     selinux_key_free,
5638         .key_permission =               selinux_key_permission,
5639         .key_getsecurity =              selinux_key_getsecurity,
5640 #endif
5641
5642 #ifdef CONFIG_AUDIT
5643         .audit_rule_init =              selinux_audit_rule_init,
5644         .audit_rule_known =             selinux_audit_rule_known,
5645         .audit_rule_match =             selinux_audit_rule_match,
5646         .audit_rule_free =              selinux_audit_rule_free,
5647 #endif
5648 };
5649
5650 static __init int selinux_init(void)
5651 {
5652         if (!security_module_enable(&selinux_ops)) {
5653                 selinux_enabled = 0;
5654                 return 0;
5655         }
5656
5657         if (!selinux_enabled) {
5658                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5659                 return 0;
5660         }
5661
5662         printk(KERN_INFO "SELinux:  Initializing.\n");
5663
5664         /* Set the security state for the initial task. */
5665         cred_init_security();
5666
5667         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5668
5669         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5670                                             sizeof(struct inode_security_struct),
5671                                             0, SLAB_PANIC, NULL);
5672         avc_init();
5673
5674         if (register_security(&selinux_ops))
5675                 panic("SELinux: Unable to register with kernel.\n");
5676
5677         if (selinux_enforcing)
5678                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5679         else
5680                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5681
5682         return 0;
5683 }
5684
5685 static void delayed_superblock_init(struct super_block *sb, void *unused)
5686 {
5687         superblock_doinit(sb, NULL);
5688 }
5689
5690 void selinux_complete_init(void)
5691 {
5692         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5693
5694         /* Set up any superblocks initialized prior to the policy load. */
5695         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5696         iterate_supers(delayed_superblock_init, NULL);
5697 }
5698
5699 /* SELinux requires early initialization in order to label
5700    all processes and objects when they are created. */
5701 security_initcall(selinux_init);
5702
5703 #if defined(CONFIG_NETFILTER)
5704
5705 static struct nf_hook_ops selinux_ipv4_ops[] = {
5706         {
5707                 .hook =         selinux_ipv4_postroute,
5708                 .owner =        THIS_MODULE,
5709                 .pf =           PF_INET,
5710                 .hooknum =      NF_INET_POST_ROUTING,
5711                 .priority =     NF_IP_PRI_SELINUX_LAST,
5712         },
5713         {
5714                 .hook =         selinux_ipv4_forward,
5715                 .owner =        THIS_MODULE,
5716                 .pf =           PF_INET,
5717                 .hooknum =      NF_INET_FORWARD,
5718                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5719         },
5720         {
5721                 .hook =         selinux_ipv4_output,
5722                 .owner =        THIS_MODULE,
5723                 .pf =           PF_INET,
5724                 .hooknum =      NF_INET_LOCAL_OUT,
5725                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5726         }
5727 };
5728
5729 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5730
5731 static struct nf_hook_ops selinux_ipv6_ops[] = {
5732         {
5733                 .hook =         selinux_ipv6_postroute,
5734                 .owner =        THIS_MODULE,
5735                 .pf =           PF_INET6,
5736                 .hooknum =      NF_INET_POST_ROUTING,
5737                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5738         },
5739         {
5740                 .hook =         selinux_ipv6_forward,
5741                 .owner =        THIS_MODULE,
5742                 .pf =           PF_INET6,
5743                 .hooknum =      NF_INET_FORWARD,
5744                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5745         }
5746 };
5747
5748 #endif  /* IPV6 */
5749
5750 static int __init selinux_nf_ip_init(void)
5751 {
5752         int err = 0;
5753
5754         if (!selinux_enabled)
5755                 goto out;
5756
5757         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5758
5759         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5760         if (err)
5761                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5762
5763 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5764         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5765         if (err)
5766                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5767 #endif  /* IPV6 */
5768
5769 out:
5770         return err;
5771 }
5772
5773 __initcall(selinux_nf_ip_init);
5774
5775 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5776 static void selinux_nf_ip_exit(void)
5777 {
5778         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5779
5780         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5781 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5782         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5783 #endif  /* IPV6 */
5784 }
5785 #endif
5786
5787 #else /* CONFIG_NETFILTER */
5788
5789 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5790 #define selinux_nf_ip_exit()
5791 #endif
5792
5793 #endif /* CONFIG_NETFILTER */
5794
5795 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5796 static int selinux_disabled;
5797
5798 int selinux_disable(void)
5799 {
5800         if (ss_initialized) {
5801                 /* Not permitted after initial policy load. */
5802                 return -EINVAL;
5803         }
5804
5805         if (selinux_disabled) {
5806                 /* Only do this once. */
5807                 return -EINVAL;
5808         }
5809
5810         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5811
5812         selinux_disabled = 1;
5813         selinux_enabled = 0;
5814
5815         reset_security_ops();
5816
5817         /* Try to destroy the avc node cache */
5818         avc_disable();
5819
5820         /* Unregister netfilter hooks. */
5821         selinux_nf_ip_exit();
5822
5823         /* Unregister selinuxfs. */
5824         exit_sel_fs();
5825
5826         return 0;
5827 }
5828 #endif