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