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