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.moore@hp.com>
  18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  19  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
  20  *
  21  *      This program is free software; you can redistribute it and/or modify
  22  *      it under the terms of the GNU General Public License version 2,
  23  *      as published by the Free Software Foundation.
  24  */
  25
  26 #include <linux/init.h>
  27 #include <linux/kd.h>
  28 #include <linux/kernel.h>
  29 #include <linux/tracehook.h>
  30 #include <linux/errno.h>
  31 #include <linux/ext2_fs.h>
  32 #include <linux/sched.h>
  33 #include <linux/security.h>
  34 #include <linux/xattr.h>
  35 #include <linux/capability.h>
  36 #include <linux/unistd.h>
  37 #include <linux/mm.h>
  38 #include <linux/mman.h>
  39 #include <linux/slab.h>
  40 #include <linux/pagemap.h>
  41 #include <linux/proc_fs.h>
  42 #include <linux/swap.h>
  43 #include <linux/spinlock.h>
  44 #include <linux/syscalls.h>
  45 #include <linux/dcache.h>
  46 #include <linux/file.h>
  47 #include <linux/fdtable.h>
  48 #include <linux/namei.h>
  49 #include <linux/mount.h>
  50 #include <linux/netfilter_ipv4.h>
  51 #include <linux/netfilter_ipv6.h>
  52 #include <linux/tty.h>
  53 #include <net/icmp.h>
  54 #include <net/ip.h>             /* for local_port_range[] */
  55 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  56 #include <net/net_namespace.h>
  57 #include <net/netlabel.h>
  58 #include <linux/uaccess.h>
  59 #include <asm/ioctls.h>
  60 #include <asm/atomic.h>
  61 #include <linux/bitops.h>
  62 #include <linux/interrupt.h>
  63 #include <linux/netdevice.h>    /* for network interface checks */
  64 #include <linux/netlink.h>
  65 #include <linux/tcp.h>
  66 #include <linux/udp.h>
  67 #include <linux/dccp.h>
  68 #include <linux/quota.h>
  69 #include <linux/un.h>           /* for Unix socket types */
  70 #include <net/af_unix.h>        /* for Unix socket types */
  71 #include <linux/parser.h>
  72 #include <linux/nfs_mount.h>
  73 #include <net/ipv6.h>
  74 #include <linux/hugetlb.h>
  75 #include <linux/personality.h>
  76 #include <linux/audit.h>
  77 #include <linux/string.h>
  78 #include <linux/selinux.h>
  79 #include <linux/mutex.h>
  80 #include <linux/posix-timers.h>
  81 #include <linux/syslog.h>
  82 #include <linux/user_namespace.h>
  83
  84 #include "avc.h"
  85 #include "objsec.h"
  86 #include "netif.h"
  87 #include "netnode.h"
  88 #include "netport.h"
  89 #include "xfrm.h"
  90 #include "netlabel.h"
  91 #include "audit.h"
  92
  93 #define NUM_SEL_MNT_OPTS 5
  94
  95 extern int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm);
  96 extern struct security_operations *security_ops;
  97
  98 /* SECMARK reference count */
  99 atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 100
 101 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 102 int selinux_enforcing;
 103
 104 static int __init enforcing_setup(char *str)
 105 {
 106         unsigned long enforcing;
 107         if (!strict_strtoul(str, 0, &enforcing))
 108                 selinux_enforcing = enforcing ? 1 : 0;
 109         return 1;
 110 }
 111 __setup("enforcing=", enforcing_setup);
 112 #endif
 113
 114 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 115 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
 116
 117 static int __init selinux_enabled_setup(char *str)
 118 {
 119         unsigned long enabled;
 120         if (!strict_strtoul(str, 0, &enabled))
 121                 selinux_enabled = enabled ? 1 : 0;
 122         return 1;
 123 }
 124 __setup("selinux=", selinux_enabled_setup);
 125 #else
 126 int selinux_enabled = 1;
 127 #endif
 128
 129 static struct kmem_cache *sel_inode_cache;
 130
 131 /**
 132  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 133  *
 134  * Description:
 135  * This function checks the SECMARK reference counter to see if any SECMARK
 136  * targets are currently configured, if the reference counter is greater than
 137  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 138  * enabled, false (0) if SECMARK is disabled.
 139  *
 140  */
 141 static int selinux_secmark_enabled(void)
 142 {
 143         return (atomic_read(&selinux_secmark_refcount) > 0);
 144 }
 145
 146 /*
 147  * initialise the security for the init task
 148  */
 149 static void cred_init_security(void)
 150 {
 151         struct cred *cred = (struct cred *) current->real_cred;
 152         struct task_security_struct *tsec;
 153
 154         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 155         if (!tsec)
 156                 panic("SELinux:  Failed to initialize initial task.\n");
 157
 158         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 159         cred->security = tsec;
 160 }
 161
 162 /*
 163  * get the security ID of a set of credentials
 164  */
 165 static inline u32 cred_sid(const struct cred *cred)
 166 {
 167         const struct task_security_struct *tsec;
 168
 169         tsec = cred->security;
 170         return tsec->sid;
 171 }
 172
 173 /*
 174  * get the objective security ID of a task
 175  */
 176 static inline u32 task_sid(const struct task_struct *task)
 177 {
 178         u32 sid;
 179
 180         rcu_read_lock();
 181         sid = cred_sid(__task_cred(task));
 182         rcu_read_unlock();
 183         return sid;
 184 }
 185
 186 /*
 187  * get the subjective security ID of the current task
 188  */
 189 static inline u32 current_sid(void)
 190 {
 191         const struct task_security_struct *tsec = current_security();
 192
 193         return tsec->sid;
 194 }
 195
 196 /* Allocate and free functions for each kind of security blob. */
 197
 198 static int inode_alloc_security(struct inode *inode)
 199 {
 200         struct inode_security_struct *isec;
 201         u32 sid = current_sid();
 202
 203         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
 204         if (!isec)
 205                 return -ENOMEM;
 206
 207         mutex_init(&isec->lock);
 208         INIT_LIST_HEAD(&isec->list);
 209         isec->inode = inode;
 210         isec->sid = SECINITSID_UNLABELED;
 211         isec->sclass = SECCLASS_FILE;
 212         isec->task_sid = sid;
 213         inode->i_security = isec;
 214
 215         return 0;
 216 }
 217
 218 static void inode_free_security(struct inode *inode)
 219 {
 220         struct inode_security_struct *isec = inode->i_security;
 221         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 222
 223         spin_lock(&sbsec->isec_lock);
 224         if (!list_empty(&isec->list))
 225                 list_del_init(&isec->list);
 226         spin_unlock(&sbsec->isec_lock);
 227
 228         inode->i_security = NULL;
 229         kmem_cache_free(sel_inode_cache, isec);
 230 }
 231
 232 static int file_alloc_security(struct file *file)
 233 {
 234         struct file_security_struct *fsec;
 235         u32 sid = current_sid();
 236
 237         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
 238         if (!fsec)
 239                 return -ENOMEM;
 240
 241         fsec->sid = sid;
 242         fsec->fown_sid = sid;
 243         file->f_security = fsec;
 244
 245         return 0;
 246 }
 247
 248 static void file_free_security(struct file *file)
 249 {
 250         struct file_security_struct *fsec = file->f_security;
 251         file->f_security = NULL;
 252         kfree(fsec);
 253 }
 254
 255 static int superblock_alloc_security(struct super_block *sb)
 256 {
 257         struct superblock_security_struct *sbsec;
 258
 259         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 260         if (!sbsec)
 261                 return -ENOMEM;
 262
 263         mutex_init(&sbsec->lock);
 264         INIT_LIST_HEAD(&sbsec->isec_head);
 265         spin_lock_init(&sbsec->isec_lock);
 266         sbsec->sb = sb;
 267         sbsec->sid = SECINITSID_UNLABELED;
 268         sbsec->def_sid = SECINITSID_FILE;
 269         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 270         sb->s_security = sbsec;
 271
 272         return 0;
 273 }
 274
 275 static void superblock_free_security(struct super_block *sb)
 276 {
 277         struct superblock_security_struct *sbsec = sb->s_security;
 278         sb->s_security = NULL;
 279         kfree(sbsec);
 280 }
 281
 282 /* The security server must be initialized before
 283    any labeling or access decisions can be provided. */
 284 extern int ss_initialized;
 285
 286 /* The file system's label must be initialized prior to use. */
 287
 288 static const char *labeling_behaviors[6] = {
 289         "uses xattr",
 290         "uses transition SIDs",
 291         "uses task SIDs",
 292         "uses genfs_contexts",
 293         "not configured for labeling",
 294         "uses mountpoint labeling",
 295 };
 296
 297 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 298
 299 static inline int inode_doinit(struct inode *inode)
 300 {
 301         return inode_doinit_with_dentry(inode, NULL);
 302 }
 303
 304 enum {
 305         Opt_error = -1,
 306         Opt_context = 1,
 307         Opt_fscontext = 2,
 308         Opt_defcontext = 3,
 309         Opt_rootcontext = 4,
 310         Opt_labelsupport = 5,
 311 };
 312
 313 static const match_table_t tokens = {
 314         {Opt_context, CONTEXT_STR "%s"},
 315         {Opt_fscontext, FSCONTEXT_STR "%s"},
 316         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 317         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 318         {Opt_labelsupport, LABELSUPP_STR},
 319         {Opt_error, NULL},
 320 };
 321
 322 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 323
 324 static int may_context_mount_sb_relabel(u32 sid,
 325                         struct superblock_security_struct *sbsec,
 326                         const struct cred *cred)
 327 {
 328         const struct task_security_struct *tsec = cred->security;
 329         int rc;
 330
 331         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 332                           FILESYSTEM__RELABELFROM, NULL);
 333         if (rc)
 334                 return rc;
 335
 336         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 337                           FILESYSTEM__RELABELTO, NULL);
 338         return rc;
 339 }
 340
 341 static int may_context_mount_inode_relabel(u32 sid,
 342                         struct superblock_security_struct *sbsec,
 343                         const struct cred *cred)
 344 {
 345         const struct task_security_struct *tsec = cred->security;
 346         int rc;
 347         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 348                           FILESYSTEM__RELABELFROM, NULL);
 349         if (rc)
 350                 return rc;
 351
 352         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 353                           FILESYSTEM__ASSOCIATE, NULL);
 354         return rc;
 355 }
 356
 357 static int sb_finish_set_opts(struct super_block *sb)
 358 {
 359         struct superblock_security_struct *sbsec = sb->s_security;
 360         struct dentry *root = sb->s_root;
 361         struct inode *root_inode = root->d_inode;
 362         int rc = 0;
 363
 364         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 365                 /* Make sure that the xattr handler exists and that no
 366                    error other than -ENODATA is returned by getxattr on
 367                    the root directory.  -ENODATA is ok, as this may be
 368                    the first boot of the SELinux kernel before we have
 369                    assigned xattr values to the filesystem. */
 370                 if (!root_inode->i_op->getxattr) {
 371                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
 372                                "xattr support\n", sb->s_id, sb->s_type->name);
 373                         rc = -EOPNOTSUPP;
 374                         goto out;
 375                 }
 376                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
 377                 if (rc < 0 && rc != -ENODATA) {
 378                         if (rc == -EOPNOTSUPP)
 379                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 380                                        "%s) has no security xattr handler\n",
 381                                        sb->s_id, sb->s_type->name);
 382                         else
 383                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 384                                        "%s) getxattr errno %d\n", sb->s_id,
 385                                        sb->s_type->name, -rc);
 386                         goto out;
 387                 }
 388         }
 389
 390         sbsec->flags |= (SE_SBINITIALIZED | SE_SBLABELSUPP);
 391
 392         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 393                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
 394                        sb->s_id, sb->s_type->name);
 395         else
 396                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type %s), %s\n",
 397                        sb->s_id, sb->s_type->name,
 398                        labeling_behaviors[sbsec->behavior-1]);
 399
 400         if (sbsec->behavior == SECURITY_FS_USE_GENFS ||
 401             sbsec->behavior == SECURITY_FS_USE_MNTPOINT ||
 402             sbsec->behavior == SECURITY_FS_USE_NONE ||
 403             sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 404                 sbsec->flags &= ~SE_SBLABELSUPP;
 405
 406         /* Special handling for sysfs. Is genfs but also has setxattr handler*/
 407         if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
 408                 sbsec->flags |= SE_SBLABELSUPP;
 409
 410         /* Initialize the root inode. */
 411         rc = inode_doinit_with_dentry(root_inode, root);
 412
 413         /* Initialize any other inodes associated with the superblock, e.g.
 414            inodes created prior to initial policy load or inodes created
 415            during get_sb by a pseudo filesystem that directly
 416            populates itself. */
 417         spin_lock(&sbsec->isec_lock);
 418 next_inode:
 419         if (!list_empty(&sbsec->isec_head)) {
 420                 struct inode_security_struct *isec =
 421                                 list_entry(sbsec->isec_head.next,
 422                                            struct inode_security_struct, list);
 423                 struct inode *inode = isec->inode;
 424                 spin_unlock(&sbsec->isec_lock);
 425                 inode = igrab(inode);
 426                 if (inode) {
 427                         if (!IS_PRIVATE(inode))
 428                                 inode_doinit(inode);
 429                         iput(inode);
 430                 }
 431                 spin_lock(&sbsec->isec_lock);
 432                 list_del_init(&isec->list);
 433                 goto next_inode;
 434         }
 435         spin_unlock(&sbsec->isec_lock);
 436 out:
 437         return rc;
 438 }
 439
 440 /*
 441  * This function should allow an FS to ask what it's mount security
 442  * options were so it can use those later for submounts, displaying
 443  * mount options, or whatever.
 444  */
 445 static int selinux_get_mnt_opts(const struct super_block *sb,
 446                                 struct security_mnt_opts *opts)
 447 {
 448         int rc = 0, i;
 449         struct superblock_security_struct *sbsec = sb->s_security;
 450         char *context = NULL;
 451         u32 len;
 452         char tmp;
 453
 454         security_init_mnt_opts(opts);
 455
 456         if (!(sbsec->flags & SE_SBINITIALIZED))
 457                 return -EINVAL;
 458
 459         if (!ss_initialized)
 460                 return -EINVAL;
 461
 462         tmp = sbsec->flags & SE_MNTMASK;
 463         /* count the number of mount options for this sb */
 464         for (i = 0; i < 8; i++) {
 465                 if (tmp & 0x01)
 466                         opts->num_mnt_opts++;
 467                 tmp >>= 1;
 468         }
 469         /* Check if the Label support flag is set */
 470         if (sbsec->flags & SE_SBLABELSUPP)
 471                 opts->num_mnt_opts++;
 472
 473         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 474         if (!opts->mnt_opts) {
 475                 rc = -ENOMEM;
 476                 goto out_free;
 477         }
 478
 479         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 480         if (!opts->mnt_opts_flags) {
 481                 rc = -ENOMEM;
 482                 goto out_free;
 483         }
 484
 485         i = 0;
 486         if (sbsec->flags & FSCONTEXT_MNT) {
 487                 rc = security_sid_to_context(sbsec->sid, &context, &len);
 488                 if (rc)
 489                         goto out_free;
 490                 opts->mnt_opts[i] = context;
 491                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 492         }
 493         if (sbsec->flags & CONTEXT_MNT) {
 494                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
 495                 if (rc)
 496                         goto out_free;
 497                 opts->mnt_opts[i] = context;
 498                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 499         }
 500         if (sbsec->flags & DEFCONTEXT_MNT) {
 501                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
 502                 if (rc)
 503                         goto out_free;
 504                 opts->mnt_opts[i] = context;
 505                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 506         }
 507         if (sbsec->flags & ROOTCONTEXT_MNT) {
 508                 struct inode *root = sbsec->sb->s_root->d_inode;
 509                 struct inode_security_struct *isec = root->i_security;
 510
 511                 rc = security_sid_to_context(isec->sid, &context, &len);
 512                 if (rc)
 513                         goto out_free;
 514                 opts->mnt_opts[i] = context;
 515                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 516         }
 517         if (sbsec->flags & SE_SBLABELSUPP) {
 518                 opts->mnt_opts[i] = NULL;
 519                 opts->mnt_opts_flags[i++] = SE_SBLABELSUPP;
 520         }
 521
 522         BUG_ON(i != opts->num_mnt_opts);
 523
 524         return 0;
 525
 526 out_free:
 527         security_free_mnt_opts(opts);
 528         return rc;
 529 }
 530
 531 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 532                       u32 old_sid, u32 new_sid)
 533 {
 534         char mnt_flags = sbsec->flags & SE_MNTMASK;
 535
 536         /* check if the old mount command had the same options */
 537         if (sbsec->flags & SE_SBINITIALIZED)
 538                 if (!(sbsec->flags & flag) ||
 539                     (old_sid != new_sid))
 540                         return 1;
 541
 542         /* check if we were passed the same options twice,
 543          * aka someone passed context=a,context=b
 544          */
 545         if (!(sbsec->flags & SE_SBINITIALIZED))
 546                 if (mnt_flags & flag)
 547                         return 1;
 548         return 0;
 549 }
 550
 551 /*
 552  * Allow filesystems with binary mount data to explicitly set mount point
 553  * labeling information.
 554  */
 555 static int selinux_set_mnt_opts(struct super_block *sb,
 556                                 struct security_mnt_opts *opts)
 557 {
 558         const struct cred *cred = current_cred();
 559         int rc = 0, i;
 560         struct superblock_security_struct *sbsec = sb->s_security;
 561         const char *name = sb->s_type->name;
 562         struct inode *inode = sbsec->sb->s_root->d_inode;
 563         struct inode_security_struct *root_isec = inode->i_security;
 564         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 565         u32 defcontext_sid = 0;
 566         char **mount_options = opts->mnt_opts;
 567         int *flags = opts->mnt_opts_flags;
 568         int num_opts = opts->num_mnt_opts;
 569
 570         mutex_lock(&sbsec->lock);
 571
 572         if (!ss_initialized) {
 573                 if (!num_opts) {
 574                         /* Defer initialization until selinux_complete_init,
 575                            after the initial policy is loaded and the security
 576                            server is ready to handle calls. */
 577                         goto out;
 578                 }
 579                 rc = -EINVAL;
 580                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
 581                         "before the security server is initialized\n");
 582                 goto out;
 583         }
 584
 585         /*
 586          * Binary mount data FS will come through this function twice.  Once
 587          * from an explicit call and once from the generic calls from the vfs.
 588          * Since the generic VFS calls will not contain any security mount data
 589          * we need to skip the double mount verification.
 590          *
 591          * This does open a hole in which we will not notice if the first
 592          * mount using this sb set explict options and a second mount using
 593          * this sb does not set any security options.  (The first options
 594          * will be used for both mounts)
 595          */
 596         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 597             && (num_opts == 0))
 598                 goto out;
 599
 600         /*
 601          * parse the mount options, check if they are valid sids.
 602          * also check if someone is trying to mount the same sb more
 603          * than once with different security options.
 604          */
 605         for (i = 0; i < num_opts; i++) {
 606                 u32 sid;
 607
 608                 if (flags[i] == SE_SBLABELSUPP)
 609                         continue;
 610                 rc = security_context_to_sid(mount_options[i],
 611                                              strlen(mount_options[i]), &sid);
 612                 if (rc) {
 613                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 614                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 615                                mount_options[i], sb->s_id, name, rc);
 616                         goto out;
 617                 }
 618                 switch (flags[i]) {
 619                 case FSCONTEXT_MNT:
 620                         fscontext_sid = sid;
 621
 622                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 623                                         fscontext_sid))
 624                                 goto out_double_mount;
 625
 626                         sbsec->flags |= FSCONTEXT_MNT;
 627                         break;
 628                 case CONTEXT_MNT:
 629                         context_sid = sid;
 630
 631                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 632                                         context_sid))
 633                                 goto out_double_mount;
 634
 635                         sbsec->flags |= CONTEXT_MNT;
 636                         break;
 637                 case ROOTCONTEXT_MNT:
 638                         rootcontext_sid = sid;
 639
 640                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 641                                         rootcontext_sid))
 642                                 goto out_double_mount;
 643
 644                         sbsec->flags |= ROOTCONTEXT_MNT;
 645
 646                         break;
 647                 case DEFCONTEXT_MNT:
 648                         defcontext_sid = sid;
 649
 650                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 651                                         defcontext_sid))
 652                                 goto out_double_mount;
 653
 654                         sbsec->flags |= DEFCONTEXT_MNT;
 655
 656                         break;
 657                 default:
 658                         rc = -EINVAL;
 659                         goto out;
 660                 }
 661         }
 662
 663         if (sbsec->flags & SE_SBINITIALIZED) {
 664                 /* previously mounted with options, but not on this attempt? */
 665                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
 666                         goto out_double_mount;
 667                 rc = 0;
 668                 goto out;
 669         }
 670
 671         if (strcmp(sb->s_type->name, "proc") == 0)
 672                 sbsec->flags |= SE_SBPROC;
 673
 674         /* Determine the labeling behavior to use for this filesystem type. */
 675         rc = security_fs_use((sbsec->flags & SE_SBPROC) ? "proc" : sb->s_type->name, &sbsec->behavior, &sbsec->sid);
 676         if (rc) {
 677                 printk(KERN_WARNING "%s: security_fs_use(%s) returned %d\n",
 678                        __func__, sb->s_type->name, rc);
 679                 goto out;
 680         }
 681
 682         /* sets the context of the superblock for the fs being mounted. */
 683         if (fscontext_sid) {
 684                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 685                 if (rc)
 686                         goto out;
 687
 688                 sbsec->sid = fscontext_sid;
 689         }
 690
 691         /*
 692          * Switch to using mount point labeling behavior.
 693          * sets the label used on all file below the mountpoint, and will set
 694          * the superblock context if not already set.
 695          */
 696         if (context_sid) {
 697                 if (!fscontext_sid) {
 698                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 699                                                           cred);
 700                         if (rc)
 701                                 goto out;
 702                         sbsec->sid = context_sid;
 703                 } else {
 704                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 705                                                              cred);
 706                         if (rc)
 707                                 goto out;
 708                 }
 709                 if (!rootcontext_sid)
 710                         rootcontext_sid = context_sid;
 711
 712                 sbsec->mntpoint_sid = context_sid;
 713                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 714         }
 715
 716         if (rootcontext_sid) {
 717                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 718                                                      cred);
 719                 if (rc)
 720                         goto out;
 721
 722                 root_isec->sid = rootcontext_sid;
 723                 root_isec->initialized = 1;
 724         }
 725
 726         if (defcontext_sid) {
 727                 if (sbsec->behavior != SECURITY_FS_USE_XATTR) {
 728                         rc = -EINVAL;
 729                         printk(KERN_WARNING "SELinux: defcontext option is "
 730                                "invalid for this filesystem type\n");
 731                         goto out;
 732                 }
 733
 734                 if (defcontext_sid != sbsec->def_sid) {
 735                         rc = may_context_mount_inode_relabel(defcontext_sid,
 736                                                              sbsec, cred);
 737                         if (rc)
 738                                 goto out;
 739                 }
 740
 741                 sbsec->def_sid = defcontext_sid;
 742         }
 743
 744         rc = sb_finish_set_opts(sb);
 745 out:
 746         mutex_unlock(&sbsec->lock);
 747         return rc;
 748 out_double_mount:
 749         rc = -EINVAL;
 750         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 751                "security settings for (dev %s, type %s)\n", sb->s_id, name);
 752         goto out;
 753 }
 754
 755 static void selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 756                                         struct super_block *newsb)
 757 {
 758         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 759         struct superblock_security_struct *newsbsec = newsb->s_security;
 760
 761         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 762         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 763         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 764
 765         /*
 766          * if the parent was able to be mounted it clearly had no special lsm
 767          * mount options.  thus we can safely deal with this superblock later
 768          */
 769         if (!ss_initialized)
 770                 return;
 771
 772         /* how can we clone if the old one wasn't set up?? */
 773         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 774
 775         /* if fs is reusing a sb, just let its options stand... */
 776         if (newsbsec->flags & SE_SBINITIALIZED)
 777                 return;
 778
 779         mutex_lock(&newsbsec->lock);
 780
 781         newsbsec->flags = oldsbsec->flags;
 782
 783         newsbsec->sid = oldsbsec->sid;
 784         newsbsec->def_sid = oldsbsec->def_sid;
 785         newsbsec->behavior = oldsbsec->behavior;
 786
 787         if (set_context) {
 788                 u32 sid = oldsbsec->mntpoint_sid;
 789
 790                 if (!set_fscontext)
 791                         newsbsec->sid = sid;
 792                 if (!set_rootcontext) {
 793                         struct inode *newinode = newsb->s_root->d_inode;
 794                         struct inode_security_struct *newisec = newinode->i_security;
 795                         newisec->sid = sid;
 796                 }
 797                 newsbsec->mntpoint_sid = sid;
 798         }
 799         if (set_rootcontext) {
 800                 const struct inode *oldinode = oldsb->s_root->d_inode;
 801                 const struct inode_security_struct *oldisec = oldinode->i_security;
 802                 struct inode *newinode = newsb->s_root->d_inode;
 803                 struct inode_security_struct *newisec = newinode->i_security;
 804
 805                 newisec->sid = oldisec->sid;
 806         }
 807
 808         sb_finish_set_opts(newsb);
 809         mutex_unlock(&newsbsec->lock);
 810 }
 811
 812 static int selinux_parse_opts_str(char *options,
 813                                   struct security_mnt_opts *opts)
 814 {
 815         char *p;
 816         char *context = NULL, *defcontext = NULL;
 817         char *fscontext = NULL, *rootcontext = NULL;
 818         int rc, num_mnt_opts = 0;
 819
 820         opts->num_mnt_opts = 0;
 821
 822         /* Standard string-based options. */
 823         while ((p = strsep(&options, "|")) != NULL) {
 824                 int token;
 825                 substring_t args[MAX_OPT_ARGS];
 826
 827                 if (!*p)
 828                         continue;
 829
 830                 token = match_token(p, tokens, args);
 831
 832                 switch (token) {
 833                 case Opt_context:
 834                         if (context || defcontext) {
 835                                 rc = -EINVAL;
 836                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 837                                 goto out_err;
 838                         }
 839                         context = match_strdup(&args[0]);
 840                         if (!context) {
 841                                 rc = -ENOMEM;
 842                                 goto out_err;
 843                         }
 844                         break;
 845
 846                 case Opt_fscontext:
 847                         if (fscontext) {
 848                                 rc = -EINVAL;
 849                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 850                                 goto out_err;
 851                         }
 852                         fscontext = match_strdup(&args[0]);
 853                         if (!fscontext) {
 854                                 rc = -ENOMEM;
 855                                 goto out_err;
 856                         }
 857                         break;
 858
 859                 case Opt_rootcontext:
 860                         if (rootcontext) {
 861                                 rc = -EINVAL;
 862                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 863                                 goto out_err;
 864                         }
 865                         rootcontext = match_strdup(&args[0]);
 866                         if (!rootcontext) {
 867                                 rc = -ENOMEM;
 868                                 goto out_err;
 869                         }
 870                         break;
 871
 872                 case Opt_defcontext:
 873                         if (context || defcontext) {
 874                                 rc = -EINVAL;
 875                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 876                                 goto out_err;
 877                         }
 878                         defcontext = match_strdup(&args[0]);
 879                         if (!defcontext) {
 880                                 rc = -ENOMEM;
 881                                 goto out_err;
 882                         }
 883                         break;
 884                 case Opt_labelsupport:
 885                         break;
 886                 default:
 887                         rc = -EINVAL;
 888                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
 889                         goto out_err;
 890
 891                 }
 892         }
 893
 894         rc = -ENOMEM;
 895         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
 896         if (!opts->mnt_opts)
 897                 goto out_err;
 898
 899         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
 900         if (!opts->mnt_opts_flags) {
 901                 kfree(opts->mnt_opts);
 902                 goto out_err;
 903         }
 904
 905         if (fscontext) {
 906                 opts->mnt_opts[num_mnt_opts] = fscontext;
 907                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
 908         }
 909         if (context) {
 910                 opts->mnt_opts[num_mnt_opts] = context;
 911                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
 912         }
 913         if (rootcontext) {
 914                 opts->mnt_opts[num_mnt_opts] = rootcontext;
 915                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
 916         }
 917         if (defcontext) {
 918                 opts->mnt_opts[num_mnt_opts] = defcontext;
 919                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
 920         }
 921
 922         opts->num_mnt_opts = num_mnt_opts;
 923         return 0;
 924
 925 out_err:
 926         kfree(context);
 927         kfree(defcontext);
 928         kfree(fscontext);
 929         kfree(rootcontext);
 930         return rc;
 931 }
 932 /*
 933  * string mount options parsing and call set the sbsec
 934  */
 935 static int superblock_doinit(struct super_block *sb, void *data)
 936 {
 937         int rc = 0;
 938         char *options = data;
 939         struct security_mnt_opts opts;
 940
 941         security_init_mnt_opts(&opts);
 942
 943         if (!data)
 944                 goto out;
 945
 946         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
 947
 948         rc = selinux_parse_opts_str(options, &opts);
 949         if (rc)
 950                 goto out_err;
 951
 952 out:
 953         rc = selinux_set_mnt_opts(sb, &opts);
 954
 955 out_err:
 956         security_free_mnt_opts(&opts);
 957         return rc;
 958 }
 959
 960 static void selinux_write_opts(struct seq_file *m,
 961                                struct security_mnt_opts *opts)
 962 {
 963         int i;
 964         char *prefix;
 965
 966         for (i = 0; i < opts->num_mnt_opts; i++) {
 967                 char *has_comma;
 968
 969                 if (opts->mnt_opts[i])
 970                         has_comma = strchr(opts->mnt_opts[i], ',');
 971                 else
 972                         has_comma = NULL;
 973
 974                 switch (opts->mnt_opts_flags[i]) {
 975                 case CONTEXT_MNT:
 976                         prefix = CONTEXT_STR;
 977                         break;
 978                 case FSCONTEXT_MNT:
 979                         prefix = FSCONTEXT_STR;
 980                         break;
 981                 case ROOTCONTEXT_MNT:
 982                         prefix = ROOTCONTEXT_STR;
 983                         break;
 984                 case DEFCONTEXT_MNT:
 985                         prefix = DEFCONTEXT_STR;
 986                         break;
 987                 case SE_SBLABELSUPP:
 988                         seq_putc(m, ',');
 989                         seq_puts(m, LABELSUPP_STR);
 990                         continue;
 991                 default:
 992                         BUG();
 993                         return;
 994                 };
 995                 /* we need a comma before each option */
 996                 seq_putc(m, ',');
 997                 seq_puts(m, prefix);
 998                 if (has_comma)
 999                         seq_putc(m, '\"');
1000                 seq_puts(m, opts->mnt_opts[i]);
1001                 if (has_comma)
1002                         seq_putc(m, '\"');
1003         }
1004 }
1005
1006 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1007 {
1008         struct security_mnt_opts opts;
1009         int rc;
1010
1011         rc = selinux_get_mnt_opts(sb, &opts);
1012         if (rc) {
1013                 /* before policy load we may get EINVAL, don't show anything */
1014                 if (rc == -EINVAL)
1015                         rc = 0;
1016                 return rc;
1017         }
1018
1019         selinux_write_opts(m, &opts);
1020
1021         security_free_mnt_opts(&opts);
1022
1023         return rc;
1024 }
1025
1026 static inline u16 inode_mode_to_security_class(umode_t mode)
1027 {
1028         switch (mode & S_IFMT) {
1029         case S_IFSOCK:
1030                 return SECCLASS_SOCK_FILE;
1031         case S_IFLNK:
1032                 return SECCLASS_LNK_FILE;
1033         case S_IFREG:
1034                 return SECCLASS_FILE;
1035         case S_IFBLK:
1036                 return SECCLASS_BLK_FILE;
1037         case S_IFDIR:
1038                 return SECCLASS_DIR;
1039         case S_IFCHR:
1040                 return SECCLASS_CHR_FILE;
1041         case S_IFIFO:
1042                 return SECCLASS_FIFO_FILE;
1043
1044         }
1045
1046         return SECCLASS_FILE;
1047 }
1048
1049 static inline int default_protocol_stream(int protocol)
1050 {
1051         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1052 }
1053
1054 static inline int default_protocol_dgram(int protocol)
1055 {
1056         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1057 }
1058
1059 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1060 {
1061         switch (family) {
1062         case PF_UNIX:
1063                 switch (type) {
1064                 case SOCK_STREAM:
1065                 case SOCK_SEQPACKET:
1066                         return SECCLASS_UNIX_STREAM_SOCKET;
1067                 case SOCK_DGRAM:
1068                         return SECCLASS_UNIX_DGRAM_SOCKET;
1069                 }
1070                 break;
1071         case PF_INET:
1072         case PF_INET6:
1073                 switch (type) {
1074                 case SOCK_STREAM:
1075                         if (default_protocol_stream(protocol))
1076                                 return SECCLASS_TCP_SOCKET;
1077                         else
1078                                 return SECCLASS_RAWIP_SOCKET;
1079                 case SOCK_DGRAM:
1080                         if (default_protocol_dgram(protocol))
1081                                 return SECCLASS_UDP_SOCKET;
1082                         else
1083                                 return SECCLASS_RAWIP_SOCKET;
1084                 case SOCK_DCCP:
1085                         return SECCLASS_DCCP_SOCKET;
1086                 default:
1087                         return SECCLASS_RAWIP_SOCKET;
1088                 }
1089                 break;
1090         case PF_NETLINK:
1091                 switch (protocol) {
1092                 case NETLINK_ROUTE:
1093                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1094                 case NETLINK_FIREWALL:
1095                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1096                 case NETLINK_INET_DIAG:
1097                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1098                 case NETLINK_NFLOG:
1099                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1100                 case NETLINK_XFRM:
1101                         return SECCLASS_NETLINK_XFRM_SOCKET;
1102                 case NETLINK_SELINUX:
1103                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1104                 case NETLINK_AUDIT:
1105                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1106                 case NETLINK_IP6_FW:
1107                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1108                 case NETLINK_DNRTMSG:
1109                         return SECCLASS_NETLINK_DNRT_SOCKET;
1110                 case NETLINK_KOBJECT_UEVENT:
1111                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1112                 default:
1113                         return SECCLASS_NETLINK_SOCKET;
1114                 }
1115         case PF_PACKET:
1116                 return SECCLASS_PACKET_SOCKET;
1117         case PF_KEY:
1118                 return SECCLASS_KEY_SOCKET;
1119         case PF_APPLETALK:
1120                 return SECCLASS_APPLETALK_SOCKET;
1121         }
1122
1123         return SECCLASS_SOCKET;
1124 }
1125
1126 #ifdef CONFIG_PROC_FS
1127 static int selinux_proc_get_sid(struct dentry *dentry,
1128                                 u16 tclass,
1129                                 u32 *sid)
1130 {
1131         int rc;
1132         char *buffer, *path;
1133
1134         buffer = (char *)__get_free_page(GFP_KERNEL);
1135         if (!buffer)
1136                 return -ENOMEM;
1137
1138         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1139         if (IS_ERR(path))
1140                 rc = PTR_ERR(path);
1141         else {
1142                 /* each process gets a /proc/PID/ entry. Strip off the
1143                  * PID part to get a valid selinux labeling.
1144                  * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1145                 while (path[1] >= '0' && path[1] <= '9') {
1146                         path[1] = '/';
1147                         path++;
1148                 }
1149                 rc = security_genfs_sid("proc", path, tclass, sid);
1150         }
1151         free_page((unsigned long)buffer);
1152         return rc;
1153 }
1154 #else
1155 static int selinux_proc_get_sid(struct dentry *dentry,
1156                                 u16 tclass,
1157                                 u32 *sid)
1158 {
1159         return -EINVAL;
1160 }
1161 #endif
1162
1163 /* The inode's security attributes must be initialized before first use. */
1164 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1165 {
1166         struct superblock_security_struct *sbsec = NULL;
1167         struct inode_security_struct *isec = inode->i_security;
1168         u32 sid;
1169         struct dentry *dentry;
1170 #define INITCONTEXTLEN 255
1171         char *context = NULL;
1172         unsigned len = 0;
1173         int rc = 0;
1174
1175         if (isec->initialized)
1176                 goto out;
1177
1178         mutex_lock(&isec->lock);
1179         if (isec->initialized)
1180                 goto out_unlock;
1181
1182         sbsec = inode->i_sb->s_security;
1183         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1184                 /* Defer initialization until selinux_complete_init,
1185                    after the initial policy is loaded and the security
1186                    server is ready to handle calls. */
1187                 spin_lock(&sbsec->isec_lock);
1188                 if (list_empty(&isec->list))
1189                         list_add(&isec->list, &sbsec->isec_head);
1190                 spin_unlock(&sbsec->isec_lock);
1191                 goto out_unlock;
1192         }
1193
1194         switch (sbsec->behavior) {
1195         case SECURITY_FS_USE_XATTR:
1196                 if (!inode->i_op->getxattr) {
1197                         isec->sid = sbsec->def_sid;
1198                         break;
1199                 }
1200
1201                 /* Need a dentry, since the xattr API requires one.
1202                    Life would be simpler if we could just pass the inode. */
1203                 if (opt_dentry) {
1204                         /* Called from d_instantiate or d_splice_alias. */
1205                         dentry = dget(opt_dentry);
1206                 } else {
1207                         /* Called from selinux_complete_init, try to find a dentry. */
1208                         dentry = d_find_alias(inode);
1209                 }
1210                 if (!dentry) {
1211                         /*
1212                          * this is can be hit on boot when a file is accessed
1213                          * before the policy is loaded.  When we load policy we
1214                          * may find inodes that have no dentry on the
1215                          * sbsec->isec_head list.  No reason to complain as these
1216                          * will get fixed up the next time we go through
1217                          * inode_doinit with a dentry, before these inodes could
1218                          * be used again by userspace.
1219                          */
1220                         goto out_unlock;
1221                 }
1222
1223                 len = INITCONTEXTLEN;
1224                 context = kmalloc(len+1, GFP_NOFS);
1225                 if (!context) {
1226                         rc = -ENOMEM;
1227                         dput(dentry);
1228                         goto out_unlock;
1229                 }
1230                 context[len] = '\0';
1231                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1232                                            context, len);
1233                 if (rc == -ERANGE) {
1234                         kfree(context);
1235
1236                         /* Need a larger buffer.  Query for the right size. */
1237                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1238                                                    NULL, 0);
1239                         if (rc < 0) {
1240                                 dput(dentry);
1241                                 goto out_unlock;
1242                         }
1243                         len = rc;
1244                         context = kmalloc(len+1, GFP_NOFS);
1245                         if (!context) {
1246                                 rc = -ENOMEM;
1247                                 dput(dentry);
1248                                 goto out_unlock;
1249                         }
1250                         context[len] = '\0';
1251                         rc = inode->i_op->getxattr(dentry,
1252                                                    XATTR_NAME_SELINUX,
1253                                                    context, len);
1254                 }
1255                 dput(dentry);
1256                 if (rc < 0) {
1257                         if (rc != -ENODATA) {
1258                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1259                                        "%d for dev=%s ino=%ld\n", __func__,
1260                                        -rc, inode->i_sb->s_id, inode->i_ino);
1261                                 kfree(context);
1262                                 goto out_unlock;
1263                         }
1264                         /* Map ENODATA to the default file SID */
1265                         sid = sbsec->def_sid;
1266                         rc = 0;
1267                 } else {
1268                         rc = security_context_to_sid_default(context, rc, &sid,
1269                                                              sbsec->def_sid,
1270                                                              GFP_NOFS);
1271                         if (rc) {
1272                                 char *dev = inode->i_sb->s_id;
1273                                 unsigned long ino = inode->i_ino;
1274
1275                                 if (rc == -EINVAL) {
1276                                         if (printk_ratelimit())
1277                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1278                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1279                                                         "filesystem in question.\n", ino, dev, context);
1280                                 } else {
1281                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1282                                                "returned %d for dev=%s ino=%ld\n",
1283                                                __func__, context, -rc, dev, ino);
1284                                 }
1285                                 kfree(context);
1286                                 /* Leave with the unlabeled SID */
1287                                 rc = 0;
1288                                 break;
1289                         }
1290                 }
1291                 kfree(context);
1292                 isec->sid = sid;
1293                 break;
1294         case SECURITY_FS_USE_TASK:
1295                 isec->sid = isec->task_sid;
1296                 break;
1297         case SECURITY_FS_USE_TRANS:
1298                 /* Default to the fs SID. */
1299                 isec->sid = sbsec->sid;
1300
1301                 /* Try to obtain a transition SID. */
1302                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1303                 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1304                                              isec->sclass, NULL, &sid);
1305                 if (rc)
1306                         goto out_unlock;
1307                 isec->sid = sid;
1308                 break;
1309         case SECURITY_FS_USE_MNTPOINT:
1310                 isec->sid = sbsec->mntpoint_sid;
1311                 break;
1312         default:
1313                 /* Default to the fs superblock SID. */
1314                 isec->sid = sbsec->sid;
1315
1316                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1317                         if (opt_dentry) {
1318                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1319                                 rc = selinux_proc_get_sid(opt_dentry,
1320                                                           isec->sclass,
1321                                                           &sid);
1322                                 if (rc)
1323                                         goto out_unlock;
1324                                 isec->sid = sid;
1325                         }
1326                 }
1327                 break;
1328         }
1329
1330         isec->initialized = 1;
1331
1332 out_unlock:
1333         mutex_unlock(&isec->lock);
1334 out:
1335         if (isec->sclass == SECCLASS_FILE)
1336                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1337         return rc;
1338 }
1339
1340 /* Convert a Linux signal to an access vector. */
1341 static inline u32 signal_to_av(int sig)
1342 {
1343         u32 perm = 0;
1344
1345         switch (sig) {
1346         case SIGCHLD:
1347                 /* Commonly granted from child to parent. */
1348                 perm = PROCESS__SIGCHLD;
1349                 break;
1350         case SIGKILL:
1351                 /* Cannot be caught or ignored */
1352                 perm = PROCESS__SIGKILL;
1353                 break;
1354         case SIGSTOP:
1355                 /* Cannot be caught or ignored */
1356                 perm = PROCESS__SIGSTOP;
1357                 break;
1358         default:
1359                 /* All other signals. */
1360                 perm = PROCESS__SIGNAL;
1361                 break;
1362         }
1363
1364         return perm;
1365 }
1366
1367 /*
1368  * Check permission between a pair of credentials
1369  * fork check, ptrace check, etc.
1370  */
1371 static int cred_has_perm(const struct cred *actor,
1372                          const struct cred *target,
1373                          u32 perms)
1374 {
1375         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1376
1377         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1378 }
1379
1380 /*
1381  * Check permission between a pair of tasks, e.g. signal checks,
1382  * fork check, ptrace check, etc.
1383  * tsk1 is the actor and tsk2 is the target
1384  * - this uses the default subjective creds of tsk1
1385  */
1386 static int task_has_perm(const struct task_struct *tsk1,
1387                          const struct task_struct *tsk2,
1388                          u32 perms)
1389 {
1390         const struct task_security_struct *__tsec1, *__tsec2;
1391         u32 sid1, sid2;
1392
1393         rcu_read_lock();
1394         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1395         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1396         rcu_read_unlock();
1397         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1398 }
1399
1400 /*
1401  * Check permission between current and another task, e.g. signal checks,
1402  * fork check, ptrace check, etc.
1403  * current is the actor and tsk2 is the target
1404  * - this uses current's subjective creds
1405  */
1406 static int current_has_perm(const struct task_struct *tsk,
1407                             u32 perms)
1408 {
1409         u32 sid, tsid;
1410
1411         sid = current_sid();
1412         tsid = task_sid(tsk);
1413         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1414 }
1415
1416 #if CAP_LAST_CAP > 63
1417 #error Fix SELinux to handle capabilities > 63.
1418 #endif
1419
1420 /* Check whether a task is allowed to use a capability. */
1421 static int task_has_capability(struct task_struct *tsk,
1422                                const struct cred *cred,
1423                                int cap, int audit)
1424 {
1425         struct common_audit_data ad;
1426         struct av_decision avd;
1427         u16 sclass;
1428         u32 sid = cred_sid(cred);
1429         u32 av = CAP_TO_MASK(cap);
1430         int rc;
1431
1432         COMMON_AUDIT_DATA_INIT(&ad, CAP);
1433         ad.tsk = tsk;
1434         ad.u.cap = cap;
1435
1436         switch (CAP_TO_INDEX(cap)) {
1437         case 0:
1438                 sclass = SECCLASS_CAPABILITY;
1439                 break;
1440         case 1:
1441                 sclass = SECCLASS_CAPABILITY2;
1442                 break;
1443         default:
1444                 printk(KERN_ERR
1445                        "SELinux:  out of range capability %d\n", cap);
1446                 BUG();
1447                 return -EINVAL;
1448         }
1449
1450         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1451         if (audit == SECURITY_CAP_AUDIT) {
1452                 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1453                 if (rc2)
1454                         return rc2;
1455         }
1456         return rc;
1457 }
1458
1459 /* Check whether a task is allowed to use a system operation. */
1460 static int task_has_system(struct task_struct *tsk,
1461                            u32 perms)
1462 {
1463         u32 sid = task_sid(tsk);
1464
1465         return avc_has_perm(sid, SECINITSID_KERNEL,
1466                             SECCLASS_SYSTEM, perms, NULL);
1467 }
1468
1469 /* Check whether a task has a particular permission to an inode.
1470    The 'adp' parameter is optional and allows other audit
1471    data to be passed (e.g. the dentry). */
1472 static int inode_has_perm(const struct cred *cred,
1473                           struct inode *inode,
1474                           u32 perms,
1475                           struct common_audit_data *adp,
1476                           unsigned flags)
1477 {
1478         struct inode_security_struct *isec;
1479         struct common_audit_data ad;
1480         u32 sid;
1481
1482         validate_creds(cred);
1483
1484         if (unlikely(IS_PRIVATE(inode)))
1485                 return 0;
1486
1487         sid = cred_sid(cred);
1488         isec = inode->i_security;
1489
1490         if (!adp) {
1491                 adp = &ad;
1492                 COMMON_AUDIT_DATA_INIT(&ad, INODE);
1493                 ad.u.inode = inode;
1494         }
1495
1496         return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1497 }
1498
1499 /* Same as inode_has_perm, but pass explicit audit data containing
1500    the dentry to help the auditing code to more easily generate the
1501    pathname if needed. */
1502 static inline int dentry_has_perm(const struct cred *cred,
1503                                   struct dentry *dentry,
1504                                   u32 av)
1505 {
1506         struct inode *inode = dentry->d_inode;
1507         struct common_audit_data ad;
1508
1509         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1510         ad.u.dentry = dentry;
1511         return inode_has_perm(cred, inode, av, &ad, 0);
1512 }
1513
1514 /* Same as inode_has_perm, but pass explicit audit data containing
1515    the path to help the auditing code to more easily generate the
1516    pathname if needed. */
1517 static inline int path_has_perm(const struct cred *cred,
1518                                 struct path *path,
1519                                 u32 av)
1520 {
1521         struct inode *inode = path->dentry->d_inode;
1522         struct common_audit_data ad;
1523
1524         COMMON_AUDIT_DATA_INIT(&ad, PATH);
1525         ad.u.path = *path;
1526         return inode_has_perm(cred, inode, av, &ad, 0);
1527 }
1528
1529 /* Check whether a task can use an open file descriptor to
1530    access an inode in a given way.  Check access to the
1531    descriptor itself, and then use dentry_has_perm to
1532    check a particular permission to the file.
1533    Access to the descriptor is implicitly granted if it
1534    has the same SID as the process.  If av is zero, then
1535    access to the file is not checked, e.g. for cases
1536    where only the descriptor is affected like seek. */
1537 static int file_has_perm(const struct cred *cred,
1538                          struct file *file,
1539                          u32 av)
1540 {
1541         struct file_security_struct *fsec = file->f_security;
1542         struct inode *inode = file->f_path.dentry->d_inode;
1543         struct common_audit_data ad;
1544         u32 sid = cred_sid(cred);
1545         int rc;
1546
1547         COMMON_AUDIT_DATA_INIT(&ad, PATH);
1548         ad.u.path = file->f_path;
1549
1550         if (sid != fsec->sid) {
1551                 rc = avc_has_perm(sid, fsec->sid,
1552                                   SECCLASS_FD,
1553                                   FD__USE,
1554                                   &ad);
1555                 if (rc)
1556                         goto out;
1557         }
1558
1559         /* av is zero if only checking access to the descriptor. */
1560         rc = 0;
1561         if (av)
1562                 rc = inode_has_perm(cred, inode, av, &ad, 0);
1563
1564 out:
1565         return rc;
1566 }
1567
1568 /* Check whether a task can create a file. */
1569 static int may_create(struct inode *dir,
1570                       struct dentry *dentry,
1571                       u16 tclass)
1572 {
1573         const struct task_security_struct *tsec = current_security();
1574         struct inode_security_struct *dsec;
1575         struct superblock_security_struct *sbsec;
1576         u32 sid, newsid;
1577         struct common_audit_data ad;
1578         int rc;
1579
1580         dsec = dir->i_security;
1581         sbsec = dir->i_sb->s_security;
1582
1583         sid = tsec->sid;
1584         newsid = tsec->create_sid;
1585
1586         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1587         ad.u.dentry = dentry;
1588
1589         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1590                           DIR__ADD_NAME | DIR__SEARCH,
1591                           &ad);
1592         if (rc)
1593                 return rc;
1594
1595         if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
1596                 rc = security_transition_sid(sid, dsec->sid, tclass,
1597                                              &dentry->d_name, &newsid);
1598                 if (rc)
1599                         return rc;
1600         }
1601
1602         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1603         if (rc)
1604                 return rc;
1605
1606         return avc_has_perm(newsid, sbsec->sid,
1607                             SECCLASS_FILESYSTEM,
1608                             FILESYSTEM__ASSOCIATE, &ad);
1609 }
1610
1611 /* Check whether a task can create a key. */
1612 static int may_create_key(u32 ksid,
1613                           struct task_struct *ctx)
1614 {
1615         u32 sid = task_sid(ctx);
1616
1617         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1618 }
1619
1620 #define MAY_LINK        0
1621 #define MAY_UNLINK      1
1622 #define MAY_RMDIR       2
1623
1624 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1625 static int may_link(struct inode *dir,
1626                     struct dentry *dentry,
1627                     int kind)
1628
1629 {
1630         struct inode_security_struct *dsec, *isec;
1631         struct common_audit_data ad;
1632         u32 sid = current_sid();
1633         u32 av;
1634         int rc;
1635
1636         dsec = dir->i_security;
1637         isec = dentry->d_inode->i_security;
1638
1639         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1640         ad.u.dentry = dentry;
1641
1642         av = DIR__SEARCH;
1643         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1644         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1645         if (rc)
1646                 return rc;
1647
1648         switch (kind) {
1649         case MAY_LINK:
1650                 av = FILE__LINK;
1651                 break;
1652         case MAY_UNLINK:
1653                 av = FILE__UNLINK;
1654                 break;
1655         case MAY_RMDIR:
1656                 av = DIR__RMDIR;
1657                 break;
1658         default:
1659                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1660                         __func__, kind);
1661                 return 0;
1662         }
1663
1664         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1665         return rc;
1666 }
1667
1668 static inline int may_rename(struct inode *old_dir,
1669                              struct dentry *old_dentry,
1670                              struct inode *new_dir,
1671                              struct dentry *new_dentry)
1672 {
1673         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1674         struct common_audit_data ad;
1675         u32 sid = current_sid();
1676         u32 av;
1677         int old_is_dir, new_is_dir;
1678         int rc;
1679
1680         old_dsec = old_dir->i_security;
1681         old_isec = old_dentry->d_inode->i_security;
1682         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1683         new_dsec = new_dir->i_security;
1684
1685         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
1686
1687         ad.u.dentry = old_dentry;
1688         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1689                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1690         if (rc)
1691                 return rc;
1692         rc = avc_has_perm(sid, old_isec->sid,
1693                           old_isec->sclass, FILE__RENAME, &ad);
1694         if (rc)
1695                 return rc;
1696         if (old_is_dir && new_dir != old_dir) {
1697                 rc = avc_has_perm(sid, old_isec->sid,
1698                                   old_isec->sclass, DIR__REPARENT, &ad);
1699                 if (rc)
1700                         return rc;
1701         }
1702
1703         ad.u.dentry = new_dentry;
1704         av = DIR__ADD_NAME | DIR__SEARCH;
1705         if (new_dentry->d_inode)
1706                 av |= DIR__REMOVE_NAME;
1707         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1708         if (rc)
1709                 return rc;
1710         if (new_dentry->d_inode) {
1711                 new_isec = new_dentry->d_inode->i_security;
1712                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1713                 rc = avc_has_perm(sid, new_isec->sid,
1714                                   new_isec->sclass,
1715                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1716                 if (rc)
1717                         return rc;
1718         }
1719
1720         return 0;
1721 }
1722
1723 /* Check whether a task can perform a filesystem operation. */
1724 static int superblock_has_perm(const struct cred *cred,
1725                                struct super_block *sb,
1726                                u32 perms,
1727                                struct common_audit_data *ad)
1728 {
1729         struct superblock_security_struct *sbsec;
1730         u32 sid = cred_sid(cred);
1731
1732         sbsec = sb->s_security;
1733         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1734 }
1735
1736 /* Convert a Linux mode and permission mask to an access vector. */
1737 static inline u32 file_mask_to_av(int mode, int mask)
1738 {
1739         u32 av = 0;
1740
1741         if ((mode & S_IFMT) != S_IFDIR) {
1742                 if (mask & MAY_EXEC)
1743                         av |= FILE__EXECUTE;
1744                 if (mask & MAY_READ)
1745                         av |= FILE__READ;
1746
1747                 if (mask & MAY_APPEND)
1748                         av |= FILE__APPEND;
1749                 else if (mask & MAY_WRITE)
1750                         av |= FILE__WRITE;
1751
1752         } else {
1753                 if (mask & MAY_EXEC)
1754                         av |= DIR__SEARCH;
1755                 if (mask & MAY_WRITE)
1756                         av |= DIR__WRITE;
1757                 if (mask & MAY_READ)
1758                         av |= DIR__READ;
1759         }
1760
1761         return av;
1762 }
1763
1764 /* Convert a Linux file to an access vector. */
1765 static inline u32 file_to_av(struct file *file)
1766 {
1767         u32 av = 0;
1768
1769         if (file->f_mode & FMODE_READ)
1770                 av |= FILE__READ;
1771         if (file->f_mode & FMODE_WRITE) {
1772                 if (file->f_flags & O_APPEND)
1773                         av |= FILE__APPEND;
1774                 else
1775                         av |= FILE__WRITE;
1776         }
1777         if (!av) {
1778                 /*
1779                  * Special file opened with flags 3 for ioctl-only use.
1780                  */
1781                 av = FILE__IOCTL;
1782         }
1783
1784         return av;
1785 }
1786
1787 /*
1788  * Convert a file to an access vector and include the correct open
1789  * open permission.
1790  */
1791 static inline u32 open_file_to_av(struct file *file)
1792 {
1793         u32 av = file_to_av(file);
1794
1795         if (selinux_policycap_openperm)
1796                 av |= FILE__OPEN;
1797
1798         return av;
1799 }
1800
1801 /* Hook functions begin here. */
1802
1803 static int selinux_ptrace_access_check(struct task_struct *child,
1804                                      unsigned int mode)
1805 {
1806         int rc;
1807
1808         rc = cap_ptrace_access_check(child, mode);
1809         if (rc)
1810                 return rc;
1811
1812         if (mode == PTRACE_MODE_READ) {
1813                 u32 sid = current_sid();
1814                 u32 csid = task_sid(child);
1815                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1816         }
1817
1818         return current_has_perm(child, PROCESS__PTRACE);
1819 }
1820
1821 static int selinux_ptrace_traceme(struct task_struct *parent)
1822 {
1823         int rc;
1824
1825         rc = cap_ptrace_traceme(parent);
1826         if (rc)
1827                 return rc;
1828
1829         return task_has_perm(parent, current, PROCESS__PTRACE);
1830 }
1831
1832 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1833                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1834 {
1835         int error;
1836
1837         error = current_has_perm(target, PROCESS__GETCAP);
1838         if (error)
1839                 return error;
1840
1841         return cap_capget(target, effective, inheritable, permitted);
1842 }
1843
1844 static int selinux_capset(struct cred *new, const struct cred *old,
1845                           const kernel_cap_t *effective,
1846                           const kernel_cap_t *inheritable,
1847                           const kernel_cap_t *permitted)
1848 {
1849         int error;
1850
1851         error = cap_capset(new, old,
1852                                       effective, inheritable, permitted);
1853         if (error)
1854                 return error;
1855
1856         return cred_has_perm(old, new, PROCESS__SETCAP);
1857 }
1858
1859 /*
1860  * (This comment used to live with the selinux_task_setuid hook,
1861  * which was removed).
1862  *
1863  * Since setuid only affects the current process, and since the SELinux
1864  * controls are not based on the Linux identity attributes, SELinux does not
1865  * need to control this operation.  However, SELinux does control the use of
1866  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1867  */
1868
1869 static int selinux_capable(struct task_struct *tsk, const struct cred *cred,
1870                            struct user_namespace *ns, int cap, int audit)
1871 {
1872         int rc;
1873
1874         rc = cap_capable(tsk, cred, ns, cap, audit);
1875         if (rc)
1876                 return rc;
1877
1878         return task_has_capability(tsk, cred, cap, audit);
1879 }
1880
1881 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1882 {
1883         const struct cred *cred = current_cred();
1884         int rc = 0;
1885
1886         if (!sb)
1887                 return 0;
1888
1889         switch (cmds) {
1890         case Q_SYNC:
1891         case Q_QUOTAON:
1892         case Q_QUOTAOFF:
1893         case Q_SETINFO:
1894         case Q_SETQUOTA:
1895                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1896                 break;
1897         case Q_GETFMT:
1898         case Q_GETINFO:
1899         case Q_GETQUOTA:
1900                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1901                 break;
1902         default:
1903                 rc = 0;  /* let the kernel handle invalid cmds */
1904                 break;
1905         }
1906         return rc;
1907 }
1908
1909 static int selinux_quota_on(struct dentry *dentry)
1910 {
1911         const struct cred *cred = current_cred();
1912
1913         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
1914 }
1915
1916 static int selinux_syslog(int type)
1917 {
1918         int rc;
1919
1920         switch (type) {
1921         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
1922         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
1923                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
1924                 break;
1925         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
1926         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
1927         /* Set level of messages printed to console */
1928         case SYSLOG_ACTION_CONSOLE_LEVEL:
1929                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
1930                 break;
1931         case SYSLOG_ACTION_CLOSE:       /* Close log */
1932         case SYSLOG_ACTION_OPEN:        /* Open log */
1933         case SYSLOG_ACTION_READ:        /* Read from log */
1934         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
1935         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
1936         default:
1937                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
1938                 break;
1939         }
1940         return rc;
1941 }
1942
1943 /*
1944  * Check that a process has enough memory to allocate a new virtual
1945  * mapping. 0 means there is enough memory for the allocation to
1946  * succeed and -ENOMEM implies there is not.
1947  *
1948  * Do not audit the selinux permission check, as this is applied to all
1949  * processes that allocate mappings.
1950  */
1951 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
1952 {
1953         int rc, cap_sys_admin = 0;
1954
1955         rc = selinux_capable(current, current_cred(),
1956                              &init_user_ns, CAP_SYS_ADMIN,
1957                              SECURITY_CAP_NOAUDIT);
1958         if (rc == 0)
1959                 cap_sys_admin = 1;
1960
1961         return __vm_enough_memory(mm, pages, cap_sys_admin);
1962 }
1963
1964 /* binprm security operations */
1965
1966 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
1967 {
1968         const struct task_security_struct *old_tsec;
1969         struct task_security_struct *new_tsec;
1970         struct inode_security_struct *isec;
1971         struct common_audit_data ad;
1972         struct inode *inode = bprm->file->f_path.dentry->d_inode;
1973         int rc;
1974
1975         rc = cap_bprm_set_creds(bprm);
1976         if (rc)
1977                 return rc;
1978
1979         /* SELinux context only depends on initial program or script and not
1980          * the script interpreter */
1981         if (bprm->cred_prepared)
1982                 return 0;
1983
1984         old_tsec = current_security();
1985         new_tsec = bprm->cred->security;
1986         isec = inode->i_security;
1987
1988         /* Default to the current task SID. */
1989         new_tsec->sid = old_tsec->sid;
1990         new_tsec->osid = old_tsec->sid;
1991
1992         /* Reset fs, key, and sock SIDs on execve. */
1993         new_tsec->create_sid = 0;
1994         new_tsec->keycreate_sid = 0;
1995         new_tsec->sockcreate_sid = 0;
1996
1997         if (old_tsec->exec_sid) {
1998                 new_tsec->sid = old_tsec->exec_sid;
1999                 /* Reset exec SID on execve. */
2000                 new_tsec->exec_sid = 0;
2001         } else {
2002                 /* Check for a default transition on this program. */
2003                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2004                                              SECCLASS_PROCESS, NULL,
2005                                              &new_tsec->sid);
2006                 if (rc)
2007                         return rc;
2008         }
2009
2010         COMMON_AUDIT_DATA_INIT(&ad, PATH);
2011         ad.u.path = bprm->file->f_path;
2012
2013         if (bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)
2014                 new_tsec->sid = old_tsec->sid;
2015
2016         if (new_tsec->sid == old_tsec->sid) {
2017                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2018                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2019                 if (rc)
2020                         return rc;
2021         } else {
2022                 /* Check permissions for the transition. */
2023                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2024                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2025                 if (rc)
2026                         return rc;
2027
2028                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2029                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2030                 if (rc)
2031                         return rc;
2032
2033                 /* Check for shared state */
2034                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2035                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2036                                           SECCLASS_PROCESS, PROCESS__SHARE,
2037                                           NULL);
2038                         if (rc)
2039                                 return -EPERM;
2040                 }
2041
2042                 /* Make sure that anyone attempting to ptrace over a task that
2043                  * changes its SID has the appropriate permit */
2044                 if (bprm->unsafe &
2045                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2046                         struct task_struct *tracer;
2047                         struct task_security_struct *sec;
2048                         u32 ptsid = 0;
2049
2050                         rcu_read_lock();
2051                         tracer = tracehook_tracer_task(current);
2052                         if (likely(tracer != NULL)) {
2053                                 sec = __task_cred(tracer)->security;
2054                                 ptsid = sec->sid;
2055                         }
2056                         rcu_read_unlock();
2057
2058                         if (ptsid != 0) {
2059                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2060                                                   SECCLASS_PROCESS,
2061                                                   PROCESS__PTRACE, NULL);
2062                                 if (rc)
2063                                         return -EPERM;
2064                         }
2065                 }
2066
2067                 /* Clear any possibly unsafe personality bits on exec: */
2068                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2069         }
2070
2071         return 0;
2072 }
2073
2074 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2075 {
2076         const struct task_security_struct *tsec = current_security();
2077         u32 sid, osid;
2078         int atsecure = 0;
2079
2080         sid = tsec->sid;
2081         osid = tsec->osid;
2082
2083         if (osid != sid) {
2084                 /* Enable secure mode for SIDs transitions unless
2085                    the noatsecure permission is granted between
2086                    the two SIDs, i.e. ahp returns 0. */
2087                 atsecure = avc_has_perm(osid, sid,
2088                                         SECCLASS_PROCESS,
2089                                         PROCESS__NOATSECURE, NULL);
2090         }
2091
2092         return (atsecure || cap_bprm_secureexec(bprm));
2093 }
2094
2095 extern struct vfsmount *selinuxfs_mount;
2096 extern struct dentry *selinux_null;
2097
2098 /* Derived from fs/exec.c:flush_old_files. */
2099 static inline void flush_unauthorized_files(const struct cred *cred,
2100                                             struct files_struct *files)
2101 {
2102         struct common_audit_data ad;
2103         struct file *file, *devnull = NULL;
2104         struct tty_struct *tty;
2105         struct fdtable *fdt;
2106         long j = -1;
2107         int drop_tty = 0;
2108
2109         tty = get_current_tty();
2110         if (tty) {
2111                 spin_lock(&tty_files_lock);
2112                 if (!list_empty(&tty->tty_files)) {
2113                         struct tty_file_private *file_priv;
2114                         struct inode *inode;
2115
2116                         /* Revalidate access to controlling tty.
2117                            Use inode_has_perm on the tty inode directly rather
2118                            than using file_has_perm, as this particular open
2119                            file may belong to another process and we are only
2120                            interested in the inode-based check here. */
2121                         file_priv = list_first_entry(&tty->tty_files,
2122                                                 struct tty_file_private, list);
2123                         file = file_priv->file;
2124                         inode = file->f_path.dentry->d_inode;
2125                         if (inode_has_perm(cred, inode,
2126                                            FILE__READ | FILE__WRITE, NULL, 0)) {
2127                                 drop_tty = 1;
2128                         }
2129                 }
2130                 spin_unlock(&tty_files_lock);
2131                 tty_kref_put(tty);
2132         }
2133         /* Reset controlling tty. */
2134         if (drop_tty)
2135                 no_tty();
2136
2137         /* Revalidate access to inherited open files. */
2138
2139         COMMON_AUDIT_DATA_INIT(&ad, INODE);
2140
2141         spin_lock(&files->file_lock);
2142         for (;;) {
2143                 unsigned long set, i;
2144                 int fd;
2145
2146                 j++;
2147                 i = j * __NFDBITS;
2148                 fdt = files_fdtable(files);
2149                 if (i >= fdt->max_fds)
2150                         break;
2151                 set = fdt->open_fds->fds_bits[j];
2152                 if (!set)
2153                         continue;
2154                 spin_unlock(&files->file_lock);
2155                 for ( ; set ; i++, set >>= 1) {
2156                         if (set & 1) {
2157                                 file = fget(i);
2158                                 if (!file)
2159                                         continue;
2160                                 if (file_has_perm(cred,
2161                                                   file,
2162                                                   file_to_av(file))) {
2163                                         sys_close(i);
2164                                         fd = get_unused_fd();
2165                                         if (fd != i) {
2166                                                 if (fd >= 0)
2167                                                         put_unused_fd(fd);
2168                                                 fput(file);
2169                                                 continue;
2170                                         }
2171                                         if (devnull) {
2172                                                 get_file(devnull);
2173                                         } else {
2174                                                 devnull = dentry_open(
2175                                                         dget(selinux_null),
2176                                                         mntget(selinuxfs_mount),
2177                                                         O_RDWR, cred);
2178                                                 if (IS_ERR(devnull)) {
2179                                                         devnull = NULL;
2180                                                         put_unused_fd(fd);
2181                                                         fput(file);
2182                                                         continue;
2183                                                 }
2184                                         }
2185                                         fd_install(fd, devnull);
2186                                 }
2187                                 fput(file);
2188                         }
2189                 }
2190                 spin_lock(&files->file_lock);
2191
2192         }
2193         spin_unlock(&files->file_lock);
2194 }
2195
2196 /*
2197  * Prepare a process for imminent new credential changes due to exec
2198  */
2199 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2200 {
2201         struct task_security_struct *new_tsec;
2202         struct rlimit *rlim, *initrlim;
2203         int rc, i;
2204
2205         new_tsec = bprm->cred->security;
2206         if (new_tsec->sid == new_tsec->osid)
2207                 return;
2208
2209         /* Close files for which the new task SID is not authorized. */
2210         flush_unauthorized_files(bprm->cred, current->files);
2211
2212         /* Always clear parent death signal on SID transitions. */
2213         current->pdeath_signal = 0;
2214
2215         /* Check whether the new SID can inherit resource limits from the old
2216          * SID.  If not, reset all soft limits to the lower of the current
2217          * task's hard limit and the init task's soft limit.
2218          *
2219          * Note that the setting of hard limits (even to lower them) can be
2220          * controlled by the setrlimit check.  The inclusion of the init task's
2221          * soft limit into the computation is to avoid resetting soft limits
2222          * higher than the default soft limit for cases where the default is
2223          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2224          */
2225         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2226                           PROCESS__RLIMITINH, NULL);
2227         if (rc) {
2228                 /* protect against do_prlimit() */
2229                 task_lock(current);
2230                 for (i = 0; i < RLIM_NLIMITS; i++) {
2231                         rlim = current->signal->rlim + i;
2232                         initrlim = init_task.signal->rlim + i;
2233                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2234                 }
2235                 task_unlock(current);
2236                 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2237         }
2238 }
2239
2240 /*
2241  * Clean up the process immediately after the installation of new credentials
2242  * due to exec
2243  */
2244 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2245 {
2246         const struct task_security_struct *tsec = current_security();
2247         struct itimerval itimer;
2248         u32 osid, sid;
2249         int rc, i;
2250
2251         osid = tsec->osid;
2252         sid = tsec->sid;
2253
2254         if (sid == osid)
2255                 return;
2256
2257         /* Check whether the new SID can inherit signal state from the old SID.
2258          * If not, clear itimers to avoid subsequent signal generation and
2259          * flush and unblock signals.
2260          *
2261          * This must occur _after_ the task SID has been updated so that any
2262          * kill done after the flush will be checked against the new SID.
2263          */
2264         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2265         if (rc) {
2266                 memset(&itimer, 0, sizeof itimer);
2267                 for (i = 0; i < 3; i++)
2268                         do_setitimer(i, &itimer, NULL);
2269                 spin_lock_irq(&current->sighand->siglock);
2270                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2271                         __flush_signals(current);
2272                         flush_signal_handlers(current, 1);
2273                         sigemptyset(&current->blocked);
2274                 }
2275                 spin_unlock_irq(&current->sighand->siglock);
2276         }
2277
2278         /* Wake up the parent if it is waiting so that it can recheck
2279          * wait permission to the new task SID. */
2280         read_lock(&tasklist_lock);
2281         __wake_up_parent(current, current->real_parent);
2282         read_unlock(&tasklist_lock);
2283 }
2284
2285 /* superblock security operations */
2286
2287 static int selinux_sb_alloc_security(struct super_block *sb)
2288 {
2289         return superblock_alloc_security(sb);
2290 }
2291
2292 static void selinux_sb_free_security(struct super_block *sb)
2293 {
2294         superblock_free_security(sb);
2295 }
2296
2297 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2298 {
2299         if (plen > olen)
2300                 return 0;
2301
2302         return !memcmp(prefix, option, plen);
2303 }
2304
2305 static inline int selinux_option(char *option, int len)
2306 {
2307         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2308                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2309                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2310                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2311                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2312 }
2313
2314 static inline void take_option(char **to, char *from, int *first, int len)
2315 {
2316         if (!*first) {
2317                 **to = ',';
2318                 *to += 1;
2319         } else
2320                 *first = 0;
2321         memcpy(*to, from, len);
2322         *to += len;
2323 }
2324
2325 static inline void take_selinux_option(char **to, char *from, int *first,
2326                                        int len)
2327 {
2328         int current_size = 0;
2329
2330         if (!*first) {
2331                 **to = '|';
2332                 *to += 1;
2333         } else
2334                 *first = 0;
2335
2336         while (current_size < len) {
2337                 if (*from != '"') {
2338                         **to = *from;
2339                         *to += 1;
2340                 }
2341                 from += 1;
2342                 current_size += 1;
2343         }
2344 }
2345
2346 static int selinux_sb_copy_data(char *orig, char *copy)
2347 {
2348         int fnosec, fsec, rc = 0;
2349         char *in_save, *in_curr, *in_end;
2350         char *sec_curr, *nosec_save, *nosec;
2351         int open_quote = 0;
2352
2353         in_curr = orig;
2354         sec_curr = copy;
2355
2356         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2357         if (!nosec) {
2358                 rc = -ENOMEM;
2359                 goto out;
2360         }
2361
2362         nosec_save = nosec;
2363         fnosec = fsec = 1;
2364         in_save = in_end = orig;
2365
2366         do {
2367                 if (*in_end == '"')
2368                         open_quote = !open_quote;
2369                 if ((*in_end == ',' && open_quote == 0) ||
2370                                 *in_end == '\0') {
2371                         int len = in_end - in_curr;
2372
2373                         if (selinux_option(in_curr, len))
2374                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2375                         else
2376                                 take_option(&nosec, in_curr, &fnosec, len);
2377
2378                         in_curr = in_end + 1;
2379                 }
2380         } while (*in_end++);
2381
2382         strcpy(in_save, nosec_save);
2383         free_page((unsigned long)nosec_save);
2384 out:
2385         return rc;
2386 }
2387
2388 static int selinux_sb_remount(struct super_block *sb, void *data)
2389 {
2390         int rc, i, *flags;
2391         struct security_mnt_opts opts;
2392         char *secdata, **mount_options;
2393         struct superblock_security_struct *sbsec = sb->s_security;
2394
2395         if (!(sbsec->flags & SE_SBINITIALIZED))
2396                 return 0;
2397
2398         if (!data)
2399                 return 0;
2400
2401         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2402                 return 0;
2403
2404         security_init_mnt_opts(&opts);
2405         secdata = alloc_secdata();
2406         if (!secdata)
2407                 return -ENOMEM;
2408         rc = selinux_sb_copy_data(data, secdata);
2409         if (rc)
2410                 goto out_free_secdata;
2411
2412         rc = selinux_parse_opts_str(secdata, &opts);
2413         if (rc)
2414                 goto out_free_secdata;
2415
2416         mount_options = opts.mnt_opts;
2417         flags = opts.mnt_opts_flags;
2418
2419         for (i = 0; i < opts.num_mnt_opts; i++) {
2420                 u32 sid;
2421                 size_t len;
2422
2423                 if (flags[i] == SE_SBLABELSUPP)
2424                         continue;
2425                 len = strlen(mount_options[i]);
2426                 rc = security_context_to_sid(mount_options[i], len, &sid);
2427                 if (rc) {
2428                         printk(KERN_WARNING "SELinux: security_context_to_sid"
2429                                "(%s) failed for (dev %s, type %s) errno=%d\n",
2430                                mount_options[i], sb->s_id, sb->s_type->name, rc);
2431                         goto out_free_opts;
2432                 }
2433                 rc = -EINVAL;
2434                 switch (flags[i]) {
2435                 case FSCONTEXT_MNT:
2436                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2437                                 goto out_bad_option;
2438                         break;
2439                 case CONTEXT_MNT:
2440                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2441                                 goto out_bad_option;
2442                         break;
2443                 case ROOTCONTEXT_MNT: {
2444                         struct inode_security_struct *root_isec;
2445                         root_isec = sb->s_root->d_inode->i_security;
2446
2447                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2448                                 goto out_bad_option;
2449                         break;
2450                 }
2451                 case DEFCONTEXT_MNT:
2452                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2453                                 goto out_bad_option;
2454                         break;
2455                 default:
2456                         goto out_free_opts;
2457                 }
2458         }
2459
2460         rc = 0;
2461 out_free_opts:
2462         security_free_mnt_opts(&opts);
2463 out_free_secdata:
2464         free_secdata(secdata);
2465         return rc;
2466 out_bad_option:
2467         printk(KERN_WARNING "SELinux: unable to change security options "
2468                "during remount (dev %s, type=%s)\n", sb->s_id,
2469                sb->s_type->name);
2470         goto out_free_opts;
2471 }
2472
2473 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2474 {
2475         const struct cred *cred = current_cred();
2476         struct common_audit_data ad;
2477         int rc;
2478
2479         rc = superblock_doinit(sb, data);
2480         if (rc)
2481                 return rc;
2482
2483         /* Allow all mounts performed by the kernel */
2484         if (flags & MS_KERNMOUNT)
2485                 return 0;
2486
2487         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2488         ad.u.dentry = sb->s_root;
2489         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2490 }
2491
2492 static int selinux_sb_statfs(struct dentry *dentry)
2493 {
2494         const struct cred *cred = current_cred();
2495         struct common_audit_data ad;
2496
2497         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2498         ad.u.dentry = dentry->d_sb->s_root;
2499         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2500 }
2501
2502 static int selinux_mount(char *dev_name,
2503                          struct path *path,
2504                          char *type,
2505                          unsigned long flags,
2506                          void *data)
2507 {
2508         const struct cred *cred = current_cred();
2509
2510         if (flags & MS_REMOUNT)
2511                 return superblock_has_perm(cred, path->mnt->mnt_sb,
2512                                            FILESYSTEM__REMOUNT, NULL);
2513         else
2514                 return path_has_perm(cred, path, FILE__MOUNTON);
2515 }
2516
2517 static int selinux_umount(struct vfsmount *mnt, int flags)
2518 {
2519         const struct cred *cred = current_cred();
2520
2521         return superblock_has_perm(cred, mnt->mnt_sb,
2522                                    FILESYSTEM__UNMOUNT, NULL);
2523 }
2524
2525 /* inode security operations */
2526
2527 static int selinux_inode_alloc_security(struct inode *inode)
2528 {
2529         return inode_alloc_security(inode);
2530 }
2531
2532 static void selinux_inode_free_security(struct inode *inode)
2533 {
2534         inode_free_security(inode);
2535 }
2536
2537 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2538                                        const struct qstr *qstr, char **name,
2539                                        void **value, size_t *len)
2540 {
2541         const struct task_security_struct *tsec = current_security();
2542         struct inode_security_struct *dsec;
2543         struct superblock_security_struct *sbsec;
2544         u32 sid, newsid, clen;
2545         int rc;
2546         char *namep = NULL, *context;
2547
2548         dsec = dir->i_security;
2549         sbsec = dir->i_sb->s_security;
2550
2551         sid = tsec->sid;
2552         newsid = tsec->create_sid;
2553
2554         if ((sbsec->flags & SE_SBINITIALIZED) &&
2555             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2556                 newsid = sbsec->mntpoint_sid;
2557         else if (!newsid || !(sbsec->flags & SE_SBLABELSUPP)) {
2558                 rc = security_transition_sid(sid, dsec->sid,
2559                                              inode_mode_to_security_class(inode->i_mode),
2560                                              qstr, &newsid);
2561                 if (rc) {
2562                         printk(KERN_WARNING "%s:  "
2563                                "security_transition_sid failed, rc=%d (dev=%s "
2564                                "ino=%ld)\n",
2565                                __func__,
2566                                -rc, inode->i_sb->s_id, inode->i_ino);
2567                         return rc;
2568                 }
2569         }
2570
2571         /* Possibly defer initialization to selinux_complete_init. */
2572         if (sbsec->flags & SE_SBINITIALIZED) {
2573                 struct inode_security_struct *isec = inode->i_security;
2574                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2575                 isec->sid = newsid;
2576                 isec->initialized = 1;
2577         }
2578
2579         if (!ss_initialized || !(sbsec->flags & SE_SBLABELSUPP))
2580                 return -EOPNOTSUPP;
2581
2582         if (name) {
2583                 namep = kstrdup(XATTR_SELINUX_SUFFIX, GFP_NOFS);
2584                 if (!namep)
2585                         return -ENOMEM;
2586                 *name = namep;
2587         }
2588
2589         if (value && len) {
2590                 rc = security_sid_to_context_force(newsid, &context, &clen);
2591                 if (rc) {
2592                         kfree(namep);
2593                         return rc;
2594                 }
2595                 *value = context;
2596                 *len = clen;
2597         }
2598
2599         return 0;
2600 }
2601
2602 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, int mask)
2603 {
2604         return may_create(dir, dentry, SECCLASS_FILE);
2605 }
2606
2607 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2608 {
2609         return may_link(dir, old_dentry, MAY_LINK);
2610 }
2611
2612 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2613 {
2614         return may_link(dir, dentry, MAY_UNLINK);
2615 }
2616
2617 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2618 {
2619         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2620 }
2621
2622 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, int mask)
2623 {
2624         return may_create(dir, dentry, SECCLASS_DIR);
2625 }
2626
2627 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2628 {
2629         return may_link(dir, dentry, MAY_RMDIR);
2630 }
2631
2632 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t dev)
2633 {
2634         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2635 }
2636
2637 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2638                                 struct inode *new_inode, struct dentry *new_dentry)
2639 {
2640         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2641 }
2642
2643 static int selinux_inode_readlink(struct dentry *dentry)
2644 {
2645         const struct cred *cred = current_cred();
2646
2647         return dentry_has_perm(cred, dentry, FILE__READ);
2648 }
2649
2650 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2651 {
2652         const struct cred *cred = current_cred();
2653
2654         return dentry_has_perm(cred, dentry, FILE__READ);
2655 }
2656
2657 static int selinux_inode_permission(struct inode *inode, int mask, unsigned flags)
2658 {
2659         const struct cred *cred = current_cred();
2660         struct common_audit_data ad;
2661         u32 perms;
2662         bool from_access;
2663
2664         from_access = mask & MAY_ACCESS;
2665         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2666
2667         /* No permission to check.  Existence test. */
2668         if (!mask)
2669                 return 0;
2670
2671         COMMON_AUDIT_DATA_INIT(&ad, INODE);
2672         ad.u.inode = inode;
2673
2674         if (from_access)
2675                 ad.selinux_audit_data.auditdeny |= FILE__AUDIT_ACCESS;
2676
2677         perms = file_mask_to_av(inode->i_mode, mask);
2678
2679         return inode_has_perm(cred, inode, perms, &ad, flags);
2680 }
2681
2682 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2683 {
2684         const struct cred *cred = current_cred();
2685         unsigned int ia_valid = iattr->ia_valid;
2686
2687         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2688         if (ia_valid & ATTR_FORCE) {
2689                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2690                               ATTR_FORCE);
2691                 if (!ia_valid)
2692                         return 0;
2693         }
2694
2695         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2696                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2697                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2698
2699         return dentry_has_perm(cred, dentry, FILE__WRITE);
2700 }
2701
2702 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2703 {
2704         const struct cred *cred = current_cred();
2705         struct path path;
2706
2707         path.dentry = dentry;
2708         path.mnt = mnt;
2709
2710         return path_has_perm(cred, &path, FILE__GETATTR);
2711 }
2712
2713 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2714 {
2715         const struct cred *cred = current_cred();
2716
2717         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2718                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2719                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2720                         if (!capable(CAP_SETFCAP))
2721                                 return -EPERM;
2722                 } else if (!capable(CAP_SYS_ADMIN)) {
2723                         /* A different attribute in the security namespace.
2724                            Restrict to administrator. */
2725                         return -EPERM;
2726                 }
2727         }
2728
2729         /* Not an attribute we recognize, so just check the
2730            ordinary setattr permission. */
2731         return dentry_has_perm(cred, dentry, FILE__SETATTR);
2732 }
2733
2734 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2735                                   const void *value, size_t size, int flags)
2736 {
2737         struct inode *inode = dentry->d_inode;
2738         struct inode_security_struct *isec = inode->i_security;
2739         struct superblock_security_struct *sbsec;
2740         struct common_audit_data ad;
2741         u32 newsid, sid = current_sid();
2742         int rc = 0;
2743
2744         if (strcmp(name, XATTR_NAME_SELINUX))
2745                 return selinux_inode_setotherxattr(dentry, name);
2746
2747         sbsec = inode->i_sb->s_security;
2748         if (!(sbsec->flags & SE_SBLABELSUPP))
2749                 return -EOPNOTSUPP;
2750
2751         if (!inode_owner_or_capable(inode))
2752                 return -EPERM;
2753
2754         COMMON_AUDIT_DATA_INIT(&ad, DENTRY);
2755         ad.u.dentry = dentry;
2756
2757         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2758                           FILE__RELABELFROM, &ad);
2759         if (rc)
2760                 return rc;
2761
2762         rc = security_context_to_sid(value, size, &newsid);
2763         if (rc == -EINVAL) {
2764                 if (!capable(CAP_MAC_ADMIN))
2765                         return rc;
2766                 rc = security_context_to_sid_force(value, size, &newsid);
2767         }
2768         if (rc)
2769                 return rc;
2770
2771         rc = avc_has_perm(sid, newsid, isec->sclass,
2772                           FILE__RELABELTO, &ad);
2773         if (rc)
2774                 return rc;
2775
2776         rc = security_validate_transition(isec->sid, newsid, sid,
2777                                           isec->sclass);
2778         if (rc)
2779                 return rc;
2780
2781         return avc_has_perm(newsid,
2782                             sbsec->sid,
2783                             SECCLASS_FILESYSTEM,
2784                             FILESYSTEM__ASSOCIATE,
2785                             &ad);
2786 }
2787
2788 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2789                                         const void *value, size_t size,
2790                                         int flags)
2791 {
2792         struct inode *inode = dentry->d_inode;
2793         struct inode_security_struct *isec = inode->i_security;
2794         u32 newsid;
2795         int rc;
2796
2797         if (strcmp(name, XATTR_NAME_SELINUX)) {
2798                 /* Not an attribute we recognize, so nothing to do. */
2799                 return;
2800         }
2801
2802         rc = security_context_to_sid_force(value, size, &newsid);
2803         if (rc) {
2804                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2805                        "for (%s, %lu), rc=%d\n",
2806                        inode->i_sb->s_id, inode->i_ino, -rc);
2807                 return;
2808         }
2809
2810         isec->sid = newsid;
2811         return;
2812 }
2813
2814 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2815 {
2816         const struct cred *cred = current_cred();
2817
2818         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2819 }
2820
2821 static int selinux_inode_listxattr(struct dentry *dentry)
2822 {
2823         const struct cred *cred = current_cred();
2824
2825         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2826 }
2827
2828 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2829 {
2830         if (strcmp(name, XATTR_NAME_SELINUX))
2831                 return selinux_inode_setotherxattr(dentry, name);
2832
2833         /* No one is allowed to remove a SELinux security label.
2834            You can change the label, but all data must be labeled. */
2835         return -EACCES;
2836 }
2837
2838 /*
2839  * Copy the inode security context value to the user.
2840  *
2841  * Permission check is handled by selinux_inode_getxattr hook.
2842  */
2843 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2844 {
2845         u32 size;
2846         int error;
2847         char *context = NULL;
2848         struct inode_security_struct *isec = inode->i_security;
2849
2850         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2851                 return -EOPNOTSUPP;
2852
2853         /*
2854          * If the caller has CAP_MAC_ADMIN, then get the raw context
2855          * value even if it is not defined by current policy; otherwise,
2856          * use the in-core value under current policy.
2857          * Use the non-auditing forms of the permission checks since
2858          * getxattr may be called by unprivileged processes commonly
2859          * and lack of permission just means that we fall back to the
2860          * in-core context value, not a denial.
2861          */
2862         error = selinux_capable(current, current_cred(),
2863                                 &init_user_ns, CAP_MAC_ADMIN,
2864                                 SECURITY_CAP_NOAUDIT);
2865         if (!error)
2866                 error = security_sid_to_context_force(isec->sid, &context,
2867                                                       &size);
2868         else
2869                 error = security_sid_to_context(isec->sid, &context, &size);
2870         if (error)
2871                 return error;
2872         error = size;
2873         if (alloc) {
2874                 *buffer = context;
2875                 goto out_nofree;
2876         }
2877         kfree(context);
2878 out_nofree:
2879         return error;
2880 }
2881
2882 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
2883                                      const void *value, size_t size, int flags)
2884 {
2885         struct inode_security_struct *isec = inode->i_security;
2886         u32 newsid;
2887         int rc;
2888
2889         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2890                 return -EOPNOTSUPP;
2891
2892         if (!value || !size)
2893                 return -EACCES;
2894
2895         rc = security_context_to_sid((void *)value, size, &newsid);
2896         if (rc)
2897                 return rc;
2898
2899         isec->sid = newsid;
2900         isec->initialized = 1;
2901         return 0;
2902 }
2903
2904 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
2905 {
2906         const int len = sizeof(XATTR_NAME_SELINUX);
2907         if (buffer && len <= buffer_size)
2908                 memcpy(buffer, XATTR_NAME_SELINUX, len);
2909         return len;
2910 }
2911
2912 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
2913 {
2914         struct inode_security_struct *isec = inode->i_security;
2915         *secid = isec->sid;
2916 }
2917
2918 /* file security operations */
2919
2920 static int selinux_revalidate_file_permission(struct file *file, int mask)
2921 {
2922         const struct cred *cred = current_cred();
2923         struct inode *inode = file->f_path.dentry->d_inode;
2924
2925         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
2926         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
2927                 mask |= MAY_APPEND;
2928
2929         return file_has_perm(cred, file,
2930                              file_mask_to_av(inode->i_mode, mask));
2931 }
2932
2933 static int selinux_file_permission(struct file *file, int mask)
2934 {
2935         struct inode *inode = file->f_path.dentry->d_inode;
2936         struct file_security_struct *fsec = file->f_security;
2937         struct inode_security_struct *isec = inode->i_security;
2938         u32 sid = current_sid();
2939
2940         if (!mask)
2941                 /* No permission to check.  Existence test. */
2942                 return 0;
2943
2944         if (sid == fsec->sid && fsec->isid == isec->sid &&
2945             fsec->pseqno == avc_policy_seqno())
2946                 /* No change since dentry_open check. */
2947                 return 0;
2948
2949         return selinux_revalidate_file_permission(file, mask);
2950 }
2951
2952 static int selinux_file_alloc_security(struct file *file)
2953 {
2954         return file_alloc_security(file);
2955 }
2956
2957 static void selinux_file_free_security(struct file *file)
2958 {
2959         file_free_security(file);
2960 }
2961
2962 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
2963                               unsigned long arg)
2964 {
2965         const struct cred *cred = current_cred();
2966         int error = 0;
2967
2968         switch (cmd) {
2969         case FIONREAD:
2970         /* fall through */
2971         case FIBMAP:
2972         /* fall through */
2973         case FIGETBSZ:
2974         /* fall through */
2975         case EXT2_IOC_GETFLAGS:
2976         /* fall through */
2977         case EXT2_IOC_GETVERSION:
2978                 error = file_has_perm(cred, file, FILE__GETATTR);
2979                 break;
2980
2981         case EXT2_IOC_SETFLAGS:
2982         /* fall through */
2983         case EXT2_IOC_SETVERSION:
2984                 error = file_has_perm(cred, file, FILE__SETATTR);
2985                 break;
2986
2987         /* sys_ioctl() checks */
2988         case FIONBIO:
2989         /* fall through */
2990         case FIOASYNC:
2991                 error = file_has_perm(cred, file, 0);
2992                 break;
2993
2994         case KDSKBENT:
2995         case KDSKBSENT:
2996                 error = task_has_capability(current, cred, CAP_SYS_TTY_CONFIG,
2997                                         SECURITY_CAP_AUDIT);
2998                 break;
2999
3000         /* default case assumes that the command will go
3001          * to the file's ioctl() function.
3002          */
3003         default:
3004                 error = file_has_perm(cred, file, FILE__IOCTL);
3005         }
3006         return error;
3007 }
3008
3009 static int default_noexec;
3010
3011 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3012 {
3013         const struct cred *cred = current_cred();
3014         int rc = 0;
3015
3016         if (default_noexec &&
3017             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3018                 /*
3019                  * We are making executable an anonymous mapping or a
3020                  * private file mapping that will also be writable.
3021                  * This has an additional check.
3022                  */
3023                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3024                 if (rc)
3025                         goto error;
3026         }
3027
3028         if (file) {
3029                 /* read access is always possible with a mapping */
3030                 u32 av = FILE__READ;
3031
3032                 /* write access only matters if the mapping is shared */
3033                 if (shared && (prot & PROT_WRITE))
3034                         av |= FILE__WRITE;
3035
3036                 if (prot & PROT_EXEC)
3037                         av |= FILE__EXECUTE;
3038
3039                 return file_has_perm(cred, file, av);
3040         }
3041
3042 error:
3043         return rc;
3044 }
3045
3046 static int selinux_file_mmap(struct file *file, unsigned long reqprot,
3047                              unsigned long prot, unsigned long flags,
3048                              unsigned long addr, unsigned long addr_only)
3049 {
3050         int rc = 0;
3051         u32 sid = current_sid();
3052
3053         /*
3054          * notice that we are intentionally putting the SELinux check before
3055          * the secondary cap_file_mmap check.  This is such a likely attempt
3056          * at bad behaviour/exploit that we always want to get the AVC, even
3057          * if DAC would have also denied the operation.
3058          */
3059         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3060                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3061                                   MEMPROTECT__MMAP_ZERO, NULL);
3062                 if (rc)
3063                         return rc;
3064         }
3065
3066         /* do DAC check on address space usage */
3067         rc = cap_file_mmap(file, reqprot, prot, flags, addr, addr_only);
3068         if (rc || addr_only)
3069                 return rc;
3070
3071         if (selinux_checkreqprot)
3072                 prot = reqprot;
3073
3074         return file_map_prot_check(file, prot,
3075                                    (flags & MAP_TYPE) == MAP_SHARED);
3076 }
3077
3078 static int selinux_file_mprotect(struct vm_area_struct *vma,
3079                                  unsigned long reqprot,
3080                                  unsigned long prot)
3081 {
3082         const struct cred *cred = current_cred();
3083
3084         if (selinux_checkreqprot)
3085                 prot = reqprot;
3086
3087         if (default_noexec &&
3088             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3089                 int rc = 0;
3090                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3091                     vma->vm_end <= vma->vm_mm->brk) {
3092                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3093                 } else if (!vma->vm_file &&
3094                            vma->vm_start <= vma->vm_mm->start_stack &&
3095                            vma->vm_end >= vma->vm_mm->start_stack) {
3096                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3097                 } else if (vma->vm_file && vma->anon_vma) {
3098                         /*
3099                          * We are making executable a file mapping that has
3100                          * had some COW done. Since pages might have been
3101                          * written, check ability to execute the possibly
3102                          * modified content.  This typically should only
3103                          * occur for text relocations.
3104                          */
3105                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3106                 }
3107                 if (rc)
3108                         return rc;
3109         }
3110
3111         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3112 }
3113
3114 static int selinux_file_lock(struct file *file, unsigned int cmd)
3115 {
3116         const struct cred *cred = current_cred();
3117
3118         return file_has_perm(cred, file, FILE__LOCK);
3119 }
3120
3121 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3122                               unsigned long arg)
3123 {
3124         const struct cred *cred = current_cred();
3125         int err = 0;
3126
3127         switch (cmd) {
3128         case F_SETFL:
3129                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3130                         err = -EINVAL;
3131                         break;
3132                 }
3133
3134                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3135                         err = file_has_perm(cred, file, FILE__WRITE);
3136                         break;
3137                 }
3138                 /* fall through */
3139         case F_SETOWN:
3140         case F_SETSIG:
3141         case F_GETFL:
3142         case F_GETOWN:
3143         case F_GETSIG:
3144                 /* Just check FD__USE permission */
3145                 err = file_has_perm(cred, file, 0);
3146                 break;
3147         case F_GETLK:
3148         case F_SETLK:
3149         case F_SETLKW:
3150 #if BITS_PER_LONG == 32
3151         case F_GETLK64:
3152         case F_SETLK64:
3153         case F_SETLKW64:
3154 #endif
3155                 if (!file->f_path.dentry || !file->f_path.dentry->d_inode) {
3156                         err = -EINVAL;
3157                         break;
3158                 }
3159                 err = file_has_perm(cred, file, FILE__LOCK);
3160                 break;
3161         }
3162
3163         return err;
3164 }
3165
3166 static int selinux_file_set_fowner(struct file *file)
3167 {
3168         struct file_security_struct *fsec;
3169
3170         fsec = file->f_security;
3171         fsec->fown_sid = current_sid();
3172
3173         return 0;
3174 }
3175
3176 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3177                                        struct fown_struct *fown, int signum)
3178 {
3179         struct file *file;
3180         u32 sid = task_sid(tsk);
3181         u32 perm;
3182         struct file_security_struct *fsec;
3183
3184         /* struct fown_struct is never outside the context of a struct file */
3185         file = container_of(fown, struct file, f_owner);
3186
3187         fsec = file->f_security;
3188
3189         if (!signum)
3190                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3191         else
3192                 perm = signal_to_av(signum);
3193
3194         return avc_has_perm(fsec->fown_sid, sid,
3195                             SECCLASS_PROCESS, perm, NULL);
3196 }
3197
3198 static int selinux_file_receive(struct file *file)
3199 {
3200         const struct cred *cred = current_cred();
3201
3202         return file_has_perm(cred, file, file_to_av(file));
3203 }
3204
3205 static int selinux_dentry_open(struct file *file, const struct cred *cred)
3206 {
3207         struct file_security_struct *fsec;
3208         struct inode *inode;
3209         struct inode_security_struct *isec;
3210
3211         inode = file->f_path.dentry->d_inode;
3212         fsec = file->f_security;
3213         isec = inode->i_security;
3214         /*
3215          * Save inode label and policy sequence number
3216          * at open-time so that selinux_file_permission
3217          * can determine whether revalidation is necessary.
3218          * Task label is already saved in the file security
3219          * struct as its SID.
3220          */
3221         fsec->isid = isec->sid;
3222         fsec->pseqno = avc_policy_seqno();
3223         /*
3224          * Since the inode label or policy seqno may have changed
3225          * between the selinux_inode_permission check and the saving
3226          * of state above, recheck that access is still permitted.
3227          * Otherwise, access might never be revalidated against the
3228          * new inode label or new policy.
3229          * This check is not redundant - do not remove.
3230          */
3231         return inode_has_perm(cred, inode, open_file_to_av(file), NULL, 0);
3232 }
3233
3234 /* task security operations */
3235
3236 static int selinux_task_create(unsigned long clone_flags)
3237 {
3238         return current_has_perm(current, PROCESS__FORK);
3239 }
3240
3241 /*
3242  * allocate the SELinux part of blank credentials
3243  */
3244 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3245 {
3246         struct task_security_struct *tsec;
3247
3248         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3249         if (!tsec)
3250                 return -ENOMEM;
3251
3252         cred->security = tsec;
3253         return 0;
3254 }
3255
3256 /*
3257  * detach and free the LSM part of a set of credentials
3258  */
3259 static void selinux_cred_free(struct cred *cred)
3260 {
3261         struct task_security_struct *tsec = cred->security;
3262
3263         /*
3264          * cred->security == NULL if security_cred_alloc_blank() or
3265          * security_prepare_creds() returned an error.
3266          */
3267         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3268         cred->security = (void *) 0x7UL;
3269         kfree(tsec);
3270 }
3271
3272 /*
3273  * prepare a new set of credentials for modification
3274  */
3275 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3276                                 gfp_t gfp)
3277 {
3278         const struct task_security_struct *old_tsec;
3279         struct task_security_struct *tsec;
3280
3281         old_tsec = old->security;
3282
3283         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3284         if (!tsec)
3285                 return -ENOMEM;
3286
3287         new->security = tsec;
3288         return 0;
3289 }
3290
3291 /*
3292  * transfer the SELinux data to a blank set of creds
3293  */
3294 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3295 {
3296         const struct task_security_struct *old_tsec = old->security;
3297         struct task_security_struct *tsec = new->security;
3298
3299         *tsec = *old_tsec;
3300 }
3301
3302 /*
3303  * set the security data for a kernel service
3304  * - all the creation contexts are set to unlabelled
3305  */
3306 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3307 {
3308         struct task_security_struct *tsec = new->security;
3309         u32 sid = current_sid();
3310         int ret;
3311
3312         ret = avc_has_perm(sid, secid,
3313                            SECCLASS_KERNEL_SERVICE,
3314                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3315                            NULL);
3316         if (ret == 0) {
3317                 tsec->sid = secid;
3318                 tsec->create_sid = 0;
3319                 tsec->keycreate_sid = 0;
3320                 tsec->sockcreate_sid = 0;
3321         }
3322         return ret;
3323 }
3324
3325 /*
3326  * set the file creation context in a security record to the same as the
3327  * objective context of the specified inode
3328  */
3329 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3330 {
3331         struct inode_security_struct *isec = inode->i_security;
3332         struct task_security_struct *tsec = new->security;
3333         u32 sid = current_sid();
3334         int ret;
3335
3336         ret = avc_has_perm(sid, isec->sid,
3337                            SECCLASS_KERNEL_SERVICE,
3338                            KERNEL_SERVICE__CREATE_FILES_AS,
3339                            NULL);
3340
3341         if (ret == 0)
3342                 tsec->create_sid = isec->sid;
3343         return ret;
3344 }
3345
3346 static int selinux_kernel_module_request(char *kmod_name)
3347 {
3348         u32 sid;
3349         struct common_audit_data ad;
3350
3351         sid = task_sid(current);
3352
3353         COMMON_AUDIT_DATA_INIT(&ad, KMOD);
3354         ad.u.kmod_name = kmod_name;
3355
3356         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3357                             SYSTEM__MODULE_REQUEST, &ad);
3358 }
3359
3360 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3361 {
3362         return current_has_perm(p, PROCESS__SETPGID);
3363 }
3364
3365 static int selinux_task_getpgid(struct task_struct *p)
3366 {
3367         return current_has_perm(p, PROCESS__GETPGID);
3368 }
3369
3370 static int selinux_task_getsid(struct task_struct *p)
3371 {
3372         return current_has_perm(p, PROCESS__GETSESSION);
3373 }
3374
3375 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3376 {
3377         *secid = task_sid(p);
3378 }
3379
3380 static int selinux_task_setnice(struct task_struct *p, int nice)
3381 {
3382         int rc;
3383
3384         rc = cap_task_setnice(p, nice);
3385         if (rc)
3386                 return rc;
3387
3388         return current_has_perm(p, PROCESS__SETSCHED);
3389 }
3390
3391 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3392 {
3393         int rc;
3394
3395         rc = cap_task_setioprio(p, ioprio);
3396         if (rc)
3397                 return rc;
3398
3399         return current_has_perm(p, PROCESS__SETSCHED);
3400 }
3401
3402 static int selinux_task_getioprio(struct task_struct *p)
3403 {
3404         return current_has_perm(p, PROCESS__GETSCHED);
3405 }
3406
3407 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3408                 struct rlimit *new_rlim)
3409 {
3410         struct rlimit *old_rlim = p->signal->rlim + resource;
3411
3412         /* Control the ability to change the hard limit (whether
3413            lowering or raising it), so that the hard limit can
3414            later be used as a safe reset point for the soft limit
3415            upon context transitions.  See selinux_bprm_committing_creds. */
3416         if (old_rlim->rlim_max != new_rlim->rlim_max)
3417                 return current_has_perm(p, PROCESS__SETRLIMIT);
3418
3419         return 0;
3420 }
3421
3422 static int selinux_task_setscheduler(struct task_struct *p)
3423 {
3424         int rc;
3425
3426         rc = cap_task_setscheduler(p);
3427         if (rc)
3428                 return rc;
3429
3430         return current_has_perm(p, PROCESS__SETSCHED);
3431 }
3432
3433 static int selinux_task_getscheduler(struct task_struct *p)
3434 {
3435         return current_has_perm(p, PROCESS__GETSCHED);
3436 }
3437
3438 static int selinux_task_movememory(struct task_struct *p)
3439 {
3440         return current_has_perm(p, PROCESS__SETSCHED);
3441 }
3442
3443 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3444                                 int sig, u32 secid)
3445 {
3446         u32 perm;
3447         int rc;
3448
3449         if (!sig)
3450                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3451         else
3452                 perm = signal_to_av(sig);
3453         if (secid)
3454                 rc = avc_has_perm(secid, task_sid(p),
3455                                   SECCLASS_PROCESS, perm, NULL);
3456         else
3457                 rc = current_has_perm(p, perm);
3458         return rc;
3459 }
3460
3461 static int selinux_task_wait(struct task_struct *p)
3462 {
3463         return task_has_perm(p, current, PROCESS__SIGCHLD);
3464 }
3465
3466 static void selinux_task_to_inode(struct task_struct *p,
3467                                   struct inode *inode)
3468 {
3469         struct inode_security_struct *isec = inode->i_security;
3470         u32 sid = task_sid(p);
3471
3472         isec->sid = sid;
3473         isec->initialized = 1;
3474 }
3475
3476 /* Returns error only if unable to parse addresses */
3477 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3478                         struct common_audit_data *ad, u8 *proto)
3479 {
3480         int offset, ihlen, ret = -EINVAL;
3481         struct iphdr _iph, *ih;
3482
3483         offset = skb_network_offset(skb);
3484         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3485         if (ih == NULL)
3486                 goto out;
3487
3488         ihlen = ih->ihl * 4;
3489         if (ihlen < sizeof(_iph))
3490                 goto out;
3491
3492         ad->u.net.v4info.saddr = ih->saddr;
3493         ad->u.net.v4info.daddr = ih->daddr;
3494         ret = 0;
3495
3496         if (proto)
3497                 *proto = ih->protocol;
3498
3499         switch (ih->protocol) {
3500         case IPPROTO_TCP: {
3501                 struct tcphdr _tcph, *th;
3502
3503                 if (ntohs(ih->frag_off) & IP_OFFSET)
3504                         break;
3505
3506                 offset += ihlen;
3507                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3508                 if (th == NULL)
3509                         break;
3510
3511                 ad->u.net.sport = th->source;
3512                 ad->u.net.dport = th->dest;
3513                 break;
3514         }
3515
3516         case IPPROTO_UDP: {
3517                 struct udphdr _udph, *uh;
3518
3519                 if (ntohs(ih->frag_off) & IP_OFFSET)
3520                         break;
3521
3522                 offset += ihlen;
3523                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3524                 if (uh == NULL)
3525                         break;
3526
3527                 ad->u.net.sport = uh->source;
3528                 ad->u.net.dport = uh->dest;
3529                 break;
3530         }
3531
3532         case IPPROTO_DCCP: {
3533                 struct dccp_hdr _dccph, *dh;
3534
3535                 if (ntohs(ih->frag_off) & IP_OFFSET)
3536                         break;
3537
3538                 offset += ihlen;
3539                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3540                 if (dh == NULL)
3541                         break;
3542
3543                 ad->u.net.sport = dh->dccph_sport;
3544                 ad->u.net.dport = dh->dccph_dport;
3545                 break;
3546         }
3547
3548         default:
3549                 break;
3550         }
3551 out:
3552         return ret;
3553 }
3554
3555 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3556
3557 /* Returns error only if unable to parse addresses */
3558 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3559                         struct common_audit_data *ad, u8 *proto)
3560 {
3561         u8 nexthdr;
3562         int ret = -EINVAL, offset;
3563         struct ipv6hdr _ipv6h, *ip6;
3564
3565         offset = skb_network_offset(skb);
3566         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3567         if (ip6 == NULL)
3568                 goto out;
3569
3570         ipv6_addr_copy(&ad->u.net.v6info.saddr, &ip6->saddr);
3571         ipv6_addr_copy(&ad->u.net.v6info.daddr, &ip6->daddr);
3572         ret = 0;
3573
3574         nexthdr = ip6->nexthdr;
3575         offset += sizeof(_ipv6h);
3576         offset = ipv6_skip_exthdr(skb, offset, &nexthdr);
3577         if (offset < 0)
3578                 goto out;
3579
3580         if (proto)
3581                 *proto = nexthdr;
3582
3583         switch (nexthdr) {
3584         case IPPROTO_TCP: {
3585                 struct tcphdr _tcph, *th;
3586
3587                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3588                 if (th == NULL)
3589                         break;
3590
3591                 ad->u.net.sport = th->source;
3592                 ad->u.net.dport = th->dest;
3593                 break;
3594         }
3595
3596         case IPPROTO_UDP: {
3597                 struct udphdr _udph, *uh;
3598
3599                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3600                 if (uh == NULL)
3601                         break;
3602
3603                 ad->u.net.sport = uh->source;
3604                 ad->u.net.dport = uh->dest;
3605                 break;
3606         }
3607
3608         case IPPROTO_DCCP: {
3609                 struct dccp_hdr _dccph, *dh;
3610
3611                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3612                 if (dh == NULL)
3613                         break;
3614
3615                 ad->u.net.sport = dh->dccph_sport;
3616                 ad->u.net.dport = dh->dccph_dport;
3617                 break;
3618         }
3619
3620         /* includes fragments */
3621         default:
3622                 break;
3623         }
3624 out:
3625         return ret;
3626 }
3627
3628 #endif /* IPV6 */
3629
3630 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3631                              char **_addrp, int src, u8 *proto)
3632 {
3633         char *addrp;
3634         int ret;
3635
3636         switch (ad->u.net.family) {
3637         case PF_INET:
3638                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3639                 if (ret)
3640                         goto parse_error;
3641                 addrp = (char *)(src ? &ad->u.net.v4info.saddr :
3642                                        &ad->u.net.v4info.daddr);
3643                 goto okay;
3644
3645 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3646         case PF_INET6:
3647                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3648                 if (ret)
3649                         goto parse_error;
3650                 addrp = (char *)(src ? &ad->u.net.v6info.saddr :
3651                                        &ad->u.net.v6info.daddr);
3652                 goto okay;
3653 #endif  /* IPV6 */
3654         default:
3655                 addrp = NULL;
3656                 goto okay;
3657         }
3658
3659 parse_error:
3660         printk(KERN_WARNING
3661                "SELinux: failure in selinux_parse_skb(),"
3662                " unable to parse packet\n");
3663         return ret;
3664
3665 okay:
3666         if (_addrp)
3667                 *_addrp = addrp;
3668         return 0;
3669 }
3670
3671 /**
3672  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3673  * @skb: the packet
3674  * @family: protocol family
3675  * @sid: the packet's peer label SID
3676  *
3677  * Description:
3678  * Check the various different forms of network peer labeling and determine
3679  * the peer label/SID for the packet; most of the magic actually occurs in
3680  * the security server function security_net_peersid_cmp().  The function
3681  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3682  * or -EACCES if @sid is invalid due to inconsistencies with the different
3683  * peer labels.
3684  *
3685  */
3686 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3687 {
3688         int err;
3689         u32 xfrm_sid;
3690         u32 nlbl_sid;
3691         u32 nlbl_type;
3692
3693         selinux_skb_xfrm_sid(skb, &xfrm_sid);
3694         selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3695
3696         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3697         if (unlikely(err)) {
3698                 printk(KERN_WARNING
3699                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3700                        " unable to determine packet's peer label\n");
3701                 return -EACCES;
3702         }
3703
3704         return 0;
3705 }
3706
3707 /* socket security operations */
3708
3709 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3710                                  u16 secclass, u32 *socksid)
3711 {
3712         if (tsec->sockcreate_sid > SECSID_NULL) {
3713                 *socksid = tsec->sockcreate_sid;
3714                 return 0;
3715         }
3716
3717         return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3718                                        socksid);
3719 }
3720
3721 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3722 {
3723         struct sk_security_struct *sksec = sk->sk_security;
3724         struct common_audit_data ad;
3725         u32 tsid = task_sid(task);
3726
3727         if (sksec->sid == SECINITSID_KERNEL)
3728                 return 0;
3729
3730         COMMON_AUDIT_DATA_INIT(&ad, NET);
3731         ad.u.net.sk = sk;
3732
3733         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3734 }
3735
3736 static int selinux_socket_create(int family, int type,
3737                                  int protocol, int kern)
3738 {
3739         const struct task_security_struct *tsec = current_security();
3740         u32 newsid;
3741         u16 secclass;
3742         int rc;
3743
3744         if (kern)
3745                 return 0;
3746
3747         secclass = socket_type_to_security_class(family, type, protocol);
3748         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3749         if (rc)
3750                 return rc;
3751
3752         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3753 }
3754
3755 static int selinux_socket_post_create(struct socket *sock, int family,
3756                                       int type, int protocol, int kern)
3757 {
3758         const struct task_security_struct *tsec = current_security();
3759         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3760         struct sk_security_struct *sksec;
3761         int err = 0;
3762
3763         isec->sclass = socket_type_to_security_class(family, type, protocol);
3764
3765         if (kern)
3766                 isec->sid = SECINITSID_KERNEL;
3767         else {
3768                 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3769                 if (err)
3770                         return err;
3771         }
3772
3773         isec->initialized = 1;
3774
3775         if (sock->sk) {
3776                 sksec = sock->sk->sk_security;
3777                 sksec->sid = isec->sid;
3778                 sksec->sclass = isec->sclass;
3779                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3780         }
3781
3782         return err;
3783 }
3784
3785 /* Range of port numbers used to automatically bind.
3786    Need to determine whether we should perform a name_bind
3787    permission check between the socket and the port number. */
3788
3789 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3790 {
3791         struct sock *sk = sock->sk;
3792         u16 family;
3793         int err;
3794
3795         err = sock_has_perm(current, sk, SOCKET__BIND);
3796         if (err)
3797                 goto out;
3798
3799         /*
3800          * If PF_INET or PF_INET6, check name_bind permission for the port.
3801          * Multiple address binding for SCTP is not supported yet: we just
3802          * check the first address now.
3803          */
3804         family = sk->sk_family;
3805         if (family == PF_INET || family == PF_INET6) {
3806                 char *addrp;
3807                 struct sk_security_struct *sksec = sk->sk_security;
3808                 struct common_audit_data ad;
3809                 struct sockaddr_in *addr4 = NULL;
3810                 struct sockaddr_in6 *addr6 = NULL;
3811                 unsigned short snum;
3812                 u32 sid, node_perm;
3813
3814                 if (family == PF_INET) {
3815                         addr4 = (struct sockaddr_in *)address;
3816                         snum = ntohs(addr4->sin_port);
3817                         addrp = (char *)&addr4->sin_addr.s_addr;
3818                 } else {
3819                         addr6 = (struct sockaddr_in6 *)address;
3820                         snum = ntohs(addr6->sin6_port);
3821                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3822                 }
3823
3824                 if (snum) {
3825                         int low, high;
3826
3827                         inet_get_local_port_range(&low, &high);
3828
3829                         if (snum < max(PROT_SOCK, low) || snum > high) {
3830                                 err = sel_netport_sid(sk->sk_protocol,
3831                                                       snum, &sid);
3832                                 if (err)
3833                                         goto out;
3834                                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3835                                 ad.u.net.sport = htons(snum);
3836                                 ad.u.net.family = family;
3837                                 err = avc_has_perm(sksec->sid, sid,
3838                                                    sksec->sclass,
3839                                                    SOCKET__NAME_BIND, &ad);
3840                                 if (err)
3841                                         goto out;
3842                         }
3843                 }
3844
3845                 switch (sksec->sclass) {
3846                 case SECCLASS_TCP_SOCKET:
3847                         node_perm = TCP_SOCKET__NODE_BIND;
3848                         break;
3849
3850                 case SECCLASS_UDP_SOCKET:
3851                         node_perm = UDP_SOCKET__NODE_BIND;
3852                         break;
3853
3854                 case SECCLASS_DCCP_SOCKET:
3855                         node_perm = DCCP_SOCKET__NODE_BIND;
3856                         break;
3857
3858                 default:
3859                         node_perm = RAWIP_SOCKET__NODE_BIND;
3860                         break;
3861                 }
3862
3863                 err = sel_netnode_sid(addrp, family, &sid);
3864                 if (err)
3865                         goto out;
3866
3867                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3868                 ad.u.net.sport = htons(snum);
3869                 ad.u.net.family = family;
3870
3871                 if (family == PF_INET)
3872                         ad.u.net.v4info.saddr = addr4->sin_addr.s_addr;
3873                 else
3874                         ipv6_addr_copy(&ad.u.net.v6info.saddr, &addr6->sin6_addr);
3875
3876                 err = avc_has_perm(sksec->sid, sid,
3877                                    sksec->sclass, node_perm, &ad);
3878                 if (err)
3879                         goto out;
3880         }
3881 out:
3882         return err;
3883 }
3884
3885 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
3886 {
3887         struct sock *sk = sock->sk;
3888         struct sk_security_struct *sksec = sk->sk_security;
3889         int err;
3890
3891         err = sock_has_perm(current, sk, SOCKET__CONNECT);
3892         if (err)
3893                 return err;
3894
3895         /*
3896          * If a TCP or DCCP socket, check name_connect permission for the port.
3897          */
3898         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
3899             sksec->sclass == SECCLASS_DCCP_SOCKET) {
3900                 struct common_audit_data ad;
3901                 struct sockaddr_in *addr4 = NULL;
3902                 struct sockaddr_in6 *addr6 = NULL;
3903                 unsigned short snum;
3904                 u32 sid, perm;
3905
3906                 if (sk->sk_family == PF_INET) {
3907                         addr4 = (struct sockaddr_in *)address;
3908                         if (addrlen < sizeof(struct sockaddr_in))
3909                                 return -EINVAL;
3910                         snum = ntohs(addr4->sin_port);
3911                 } else {
3912                         addr6 = (struct sockaddr_in6 *)address;
3913                         if (addrlen < SIN6_LEN_RFC2133)
3914                                 return -EINVAL;
3915                         snum = ntohs(addr6->sin6_port);
3916                 }
3917
3918                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
3919                 if (err)
3920                         goto out;
3921
3922                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
3923                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
3924
3925                 COMMON_AUDIT_DATA_INIT(&ad, NET);
3926                 ad.u.net.dport = htons(snum);
3927                 ad.u.net.family = sk->sk_family;
3928                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
3929                 if (err)
3930                         goto out;
3931         }
3932
3933         err = selinux_netlbl_socket_connect(sk, address);
3934
3935 out:
3936         return err;
3937 }
3938
3939 static int selinux_socket_listen(struct socket *sock, int backlog)
3940 {
3941         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
3942 }
3943
3944 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
3945 {
3946         int err;
3947         struct inode_security_struct *isec;
3948         struct inode_security_struct *newisec;
3949
3950         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
3951         if (err)
3952                 return err;
3953
3954         newisec = SOCK_INODE(newsock)->i_security;
3955
3956         isec = SOCK_INODE(sock)->i_security;
3957         newisec->sclass = isec->sclass;
3958         newisec->sid = isec->sid;
3959         newisec->initialized = 1;
3960
3961         return 0;
3962 }
3963
3964 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
3965                                   int size)
3966 {
3967         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
3968 }
3969
3970 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
3971                                   int size, int flags)
3972 {
3973         return sock_has_perm(current, sock->sk, SOCKET__READ);
3974 }
3975
3976 static int selinux_socket_getsockname(struct socket *sock)
3977 {
3978         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3979 }
3980
3981 static int selinux_socket_getpeername(struct socket *sock)
3982 {
3983         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
3984 }
3985
3986 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
3987 {
3988         int err;
3989
3990         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
3991         if (err)
3992                 return err;
3993
3994         return selinux_netlbl_socket_setsockopt(sock, level, optname);
3995 }
3996
3997 static int selinux_socket_getsockopt(struct socket *sock, int level,
3998                                      int optname)
3999 {
4000         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4001 }
4002
4003 static int selinux_socket_shutdown(struct socket *sock, int how)
4004 {
4005         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4006 }
4007
4008 static int selinux_socket_unix_stream_connect(struct sock *sock,
4009                                               struct sock *other,
4010                                               struct sock *newsk)
4011 {
4012         struct sk_security_struct *sksec_sock = sock->sk_security;
4013         struct sk_security_struct *sksec_other = other->sk_security;
4014         struct sk_security_struct *sksec_new = newsk->sk_security;
4015         struct common_audit_data ad;
4016         int err;
4017
4018         COMMON_AUDIT_DATA_INIT(&ad, NET);
4019         ad.u.net.sk = other;
4020
4021         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4022                            sksec_other->sclass,
4023                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4024         if (err)
4025                 return err;
4026
4027         /* server child socket */
4028         sksec_new->peer_sid = sksec_sock->sid;
4029         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4030                                     &sksec_new->sid);
4031         if (err)
4032                 return err;
4033
4034         /* connecting socket */
4035         sksec_sock->peer_sid = sksec_new->sid;
4036
4037         return 0;
4038 }
4039
4040 static int selinux_socket_unix_may_send(struct socket *sock,
4041                                         struct socket *other)
4042 {
4043         struct sk_security_struct *ssec = sock->sk->sk_security;
4044         struct sk_security_struct *osec = other->sk->sk_security;
4045         struct common_audit_data ad;
4046
4047         COMMON_AUDIT_DATA_INIT(&ad, NET);
4048         ad.u.net.sk = other->sk;
4049
4050         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4051                             &ad);
4052 }
4053
4054 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4055                                     u32 peer_sid,
4056                                     struct common_audit_data *ad)
4057 {
4058         int err;
4059         u32 if_sid;
4060         u32 node_sid;
4061
4062         err = sel_netif_sid(ifindex, &if_sid);
4063         if (err)
4064                 return err;
4065         err = avc_has_perm(peer_sid, if_sid,
4066                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4067         if (err)
4068                 return err;
4069
4070         err = sel_netnode_sid(addrp, family, &node_sid);
4071         if (err)
4072                 return err;
4073         return avc_has_perm(peer_sid, node_sid,
4074                             SECCLASS_NODE, NODE__RECVFROM, ad);
4075 }
4076
4077 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4078                                        u16 family)
4079 {
4080         int err = 0;
4081         struct sk_security_struct *sksec = sk->sk_security;
4082         u32 sk_sid = sksec->sid;
4083         struct common_audit_data ad;
4084         char *addrp;
4085
4086         COMMON_AUDIT_DATA_INIT(&ad, NET);
4087         ad.u.net.netif = skb->skb_iif;
4088         ad.u.net.family = family;
4089         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4090         if (err)
4091                 return err;
4092
4093         if (selinux_secmark_enabled()) {
4094                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4095                                    PACKET__RECV, &ad);
4096                 if (err)
4097                         return err;
4098         }
4099
4100         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4101         if (err)
4102                 return err;
4103         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4104
4105         return err;
4106 }
4107
4108 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4109 {
4110         int err;
4111         struct sk_security_struct *sksec = sk->sk_security;
4112         u16 family = sk->sk_family;
4113         u32 sk_sid = sksec->sid;
4114         struct common_audit_data ad;
4115         char *addrp;
4116         u8 secmark_active;
4117         u8 peerlbl_active;
4118
4119         if (family != PF_INET && family != PF_INET6)
4120                 return 0;
4121
4122         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4123         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4124                 family = PF_INET;
4125
4126         /* If any sort of compatibility mode is enabled then handoff processing
4127          * to the selinux_sock_rcv_skb_compat() function to deal with the
4128          * special handling.  We do this in an attempt to keep this function
4129          * as fast and as clean as possible. */
4130         if (!selinux_policycap_netpeer)
4131                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4132
4133         secmark_active = selinux_secmark_enabled();
4134         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4135         if (!secmark_active && !peerlbl_active)
4136                 return 0;
4137
4138         COMMON_AUDIT_DATA_INIT(&ad, NET);
4139         ad.u.net.netif = skb->skb_iif;
4140         ad.u.net.family = family;
4141         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4142         if (err)
4143                 return err;
4144
4145         if (peerlbl_active) {
4146                 u32 peer_sid;
4147
4148                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4149                 if (err)
4150                         return err;
4151                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4152                                                peer_sid, &ad);
4153                 if (err) {
4154                         selinux_netlbl_err(skb, err, 0);
4155                         return err;
4156                 }
4157                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4158                                    PEER__RECV, &ad);
4159                 if (err)
4160                         selinux_netlbl_err(skb, err, 0);
4161         }
4162
4163         if (secmark_active) {
4164                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4165                                    PACKET__RECV, &ad);
4166                 if (err)
4167                         return err;
4168         }
4169
4170         return err;
4171 }
4172
4173 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4174                                             int __user *optlen, unsigned len)
4175 {
4176         int err = 0;
4177         char *scontext;
4178         u32 scontext_len;
4179         struct sk_security_struct *sksec = sock->sk->sk_security;
4180         u32 peer_sid = SECSID_NULL;
4181
4182         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4183             sksec->sclass == SECCLASS_TCP_SOCKET)
4184                 peer_sid = sksec->peer_sid;
4185         if (peer_sid == SECSID_NULL)
4186                 return -ENOPROTOOPT;
4187
4188         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4189         if (err)
4190                 return err;
4191
4192         if (scontext_len > len) {
4193                 err = -ERANGE;
4194                 goto out_len;
4195         }
4196
4197         if (copy_to_user(optval, scontext, scontext_len))
4198                 err = -EFAULT;
4199
4200 out_len:
4201         if (put_user(scontext_len, optlen))
4202                 err = -EFAULT;
4203         kfree(scontext);
4204         return err;
4205 }
4206
4207 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4208 {
4209         u32 peer_secid = SECSID_NULL;
4210         u16 family;
4211
4212         if (skb && skb->protocol == htons(ETH_P_IP))
4213                 family = PF_INET;
4214         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4215                 family = PF_INET6;
4216         else if (sock)
4217                 family = sock->sk->sk_family;
4218         else
4219                 goto out;
4220
4221         if (sock && family == PF_UNIX)
4222                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4223         else if (skb)
4224                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4225
4226 out:
4227         *secid = peer_secid;
4228         if (peer_secid == SECSID_NULL)
4229                 return -EINVAL;
4230         return 0;
4231 }
4232
4233 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4234 {
4235         struct sk_security_struct *sksec;
4236
4237         sksec = kzalloc(sizeof(*sksec), priority);
4238         if (!sksec)
4239                 return -ENOMEM;
4240
4241         sksec->peer_sid = SECINITSID_UNLABELED;
4242         sksec->sid = SECINITSID_UNLABELED;
4243         selinux_netlbl_sk_security_reset(sksec);
4244         sk->sk_security = sksec;
4245
4246         return 0;
4247 }
4248
4249 static void selinux_sk_free_security(struct sock *sk)
4250 {
4251         struct sk_security_struct *sksec = sk->sk_security;
4252
4253         sk->sk_security = NULL;
4254         selinux_netlbl_sk_security_free(sksec);
4255         kfree(sksec);
4256 }
4257
4258 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4259 {
4260         struct sk_security_struct *sksec = sk->sk_security;
4261         struct sk_security_struct *newsksec = newsk->sk_security;
4262
4263         newsksec->sid = sksec->sid;
4264         newsksec->peer_sid = sksec->peer_sid;
4265         newsksec->sclass = sksec->sclass;
4266
4267         selinux_netlbl_sk_security_reset(newsksec);
4268 }
4269
4270 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4271 {
4272         if (!sk)
4273                 *secid = SECINITSID_ANY_SOCKET;
4274         else {
4275                 struct sk_security_struct *sksec = sk->sk_security;
4276
4277                 *secid = sksec->sid;
4278         }
4279 }
4280
4281 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4282 {
4283         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4284         struct sk_security_struct *sksec = sk->sk_security;
4285
4286         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4287             sk->sk_family == PF_UNIX)
4288                 isec->sid = sksec->sid;
4289         sksec->sclass = isec->sclass;
4290 }
4291
4292 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4293                                      struct request_sock *req)
4294 {
4295         struct sk_security_struct *sksec = sk->sk_security;
4296         int err;
4297         u16 family = sk->sk_family;
4298         u32 newsid;
4299         u32 peersid;
4300
4301         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4302         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4303                 family = PF_INET;
4304
4305         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4306         if (err)
4307                 return err;
4308         if (peersid == SECSID_NULL) {
4309                 req->secid = sksec->sid;
4310                 req->peer_secid = SECSID_NULL;
4311         } else {
4312                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4313                 if (err)
4314                         return err;
4315                 req->secid = newsid;
4316                 req->peer_secid = peersid;
4317         }
4318
4319         return selinux_netlbl_inet_conn_request(req, family);
4320 }
4321
4322 static void selinux_inet_csk_clone(struct sock *newsk,
4323                                    const struct request_sock *req)
4324 {
4325         struct sk_security_struct *newsksec = newsk->sk_security;
4326
4327         newsksec->sid = req->secid;
4328         newsksec->peer_sid = req->peer_secid;
4329         /* NOTE: Ideally, we should also get the isec->sid for the
4330            new socket in sync, but we don't have the isec available yet.
4331            So we will wait until sock_graft to do it, by which
4332            time it will have been created and available. */
4333
4334         /* We don't need to take any sort of lock here as we are the only
4335          * thread with access to newsksec */
4336         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4337 }
4338
4339 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4340 {
4341         u16 family = sk->sk_family;
4342         struct sk_security_struct *sksec = sk->sk_security;
4343
4344         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4345         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4346                 family = PF_INET;
4347
4348         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4349 }
4350
4351 static int selinux_secmark_relabel_packet(u32 sid)
4352 {
4353         const struct task_security_struct *__tsec;
4354         u32 tsid;
4355
4356         __tsec = current_security();
4357         tsid = __tsec->sid;
4358
4359         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4360 }
4361
4362 static void selinux_secmark_refcount_inc(void)
4363 {
4364         atomic_inc(&selinux_secmark_refcount);
4365 }
4366
4367 static void selinux_secmark_refcount_dec(void)
4368 {
4369         atomic_dec(&selinux_secmark_refcount);
4370 }
4371
4372 static void selinux_req_classify_flow(const struct request_sock *req,
4373                                       struct flowi *fl)
4374 {
4375         fl->flowi_secid = req->secid;
4376 }
4377
4378 static int selinux_tun_dev_create(void)
4379 {
4380         u32 sid = current_sid();
4381
4382         /* we aren't taking into account the "sockcreate" SID since the socket
4383          * that is being created here is not a socket in the traditional sense,
4384          * instead it is a private sock, accessible only to the kernel, and
4385          * representing a wide range of network traffic spanning multiple
4386          * connections unlike traditional sockets - check the TUN driver to
4387          * get a better understanding of why this socket is special */
4388
4389         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4390                             NULL);
4391 }
4392
4393 static void selinux_tun_dev_post_create(struct sock *sk)
4394 {
4395         struct sk_security_struct *sksec = sk->sk_security;
4396
4397         /* we don't currently perform any NetLabel based labeling here and it
4398          * isn't clear that we would want to do so anyway; while we could apply
4399          * labeling without the support of the TUN user the resulting labeled
4400          * traffic from the other end of the connection would almost certainly
4401          * cause confusion to the TUN user that had no idea network labeling
4402          * protocols were being used */
4403
4404         /* see the comments in selinux_tun_dev_create() about why we don't use
4405          * the sockcreate SID here */
4406
4407         sksec->sid = current_sid();
4408         sksec->sclass = SECCLASS_TUN_SOCKET;
4409 }
4410
4411 static int selinux_tun_dev_attach(struct sock *sk)
4412 {
4413         struct sk_security_struct *sksec = sk->sk_security;
4414         u32 sid = current_sid();
4415         int err;
4416
4417         err = avc_has_perm(sid, sksec->sid, SECCLASS_TUN_SOCKET,
4418                            TUN_SOCKET__RELABELFROM, NULL);
4419         if (err)
4420                 return err;
4421         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4422                            TUN_SOCKET__RELABELTO, NULL);
4423         if (err)
4424                 return err;
4425
4426         sksec->sid = sid;
4427
4428         return 0;
4429 }
4430
4431 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4432 {
4433         int err = 0;
4434         u32 perm;
4435         struct nlmsghdr *nlh;
4436         struct sk_security_struct *sksec = sk->sk_security;
4437
4438         if (skb->len < NLMSG_SPACE(0)) {
4439                 err = -EINVAL;
4440                 goto out;
4441         }
4442         nlh = nlmsg_hdr(skb);
4443
4444         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4445         if (err) {
4446                 if (err == -EINVAL) {
4447                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4448                                   "SELinux:  unrecognized netlink message"
4449                                   " type=%hu for sclass=%hu\n",
4450                                   nlh->nlmsg_type, sksec->sclass);
4451                         if (!selinux_enforcing || security_get_allow_unknown())
4452                                 err = 0;
4453                 }
4454
4455                 /* Ignore */
4456                 if (err == -ENOENT)
4457                         err = 0;
4458                 goto out;
4459         }
4460
4461         err = sock_has_perm(current, sk, perm);
4462 out:
4463         return err;
4464 }
4465
4466 #ifdef CONFIG_NETFILTER
4467
4468 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4469                                        u16 family)
4470 {
4471         int err;
4472         char *addrp;
4473         u32 peer_sid;
4474         struct common_audit_data ad;
4475         u8 secmark_active;
4476         u8 netlbl_active;
4477         u8 peerlbl_active;
4478
4479         if (!selinux_policycap_netpeer)
4480                 return NF_ACCEPT;
4481
4482         secmark_active = selinux_secmark_enabled();
4483         netlbl_active = netlbl_enabled();
4484         peerlbl_active = netlbl_active || selinux_xfrm_enabled();
4485         if (!secmark_active && !peerlbl_active)
4486                 return NF_ACCEPT;
4487
4488         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4489                 return NF_DROP;
4490
4491         COMMON_AUDIT_DATA_INIT(&ad, NET);
4492         ad.u.net.netif = ifindex;
4493         ad.u.net.family = family;
4494         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4495                 return NF_DROP;
4496
4497         if (peerlbl_active) {
4498                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4499                                                peer_sid, &ad);
4500                 if (err) {
4501                         selinux_netlbl_err(skb, err, 1);
4502                         return NF_DROP;
4503                 }
4504         }
4505
4506         if (secmark_active)
4507                 if (avc_has_perm(peer_sid, skb->secmark,
4508                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4509                         return NF_DROP;
4510
4511         if (netlbl_active)
4512                 /* we do this in the FORWARD path and not the POST_ROUTING
4513                  * path because we want to make sure we apply the necessary
4514                  * labeling before IPsec is applied so we can leverage AH
4515                  * protection */
4516                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4517                         return NF_DROP;
4518
4519         return NF_ACCEPT;
4520 }
4521
4522 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4523                                          struct sk_buff *skb,
4524                                          const struct net_device *in,
4525                                          const struct net_device *out,
4526                                          int (*okfn)(struct sk_buff *))
4527 {
4528         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4529 }
4530
4531 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4532 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4533                                          struct sk_buff *skb,
4534                                          const struct net_device *in,
4535                                          const struct net_device *out,
4536                                          int (*okfn)(struct sk_buff *))
4537 {
4538         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4539 }
4540 #endif  /* IPV6 */
4541
4542 static unsigned int selinux_ip_output(struct sk_buff *skb,
4543                                       u16 family)
4544 {
4545         u32 sid;
4546
4547         if (!netlbl_enabled())
4548                 return NF_ACCEPT;
4549
4550         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4551          * because we want to make sure we apply the necessary labeling
4552          * before IPsec is applied so we can leverage AH protection */
4553         if (skb->sk) {
4554                 struct sk_security_struct *sksec = skb->sk->sk_security;
4555                 sid = sksec->sid;
4556         } else
4557                 sid = SECINITSID_KERNEL;
4558         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4559                 return NF_DROP;
4560
4561         return NF_ACCEPT;
4562 }
4563
4564 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4565                                         struct sk_buff *skb,
4566                                         const struct net_device *in,
4567                                         const struct net_device *out,
4568                                         int (*okfn)(struct sk_buff *))
4569 {
4570         return selinux_ip_output(skb, PF_INET);
4571 }
4572
4573 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4574                                                 int ifindex,
4575                                                 u16 family)
4576 {
4577         struct sock *sk = skb->sk;
4578         struct sk_security_struct *sksec;
4579         struct common_audit_data ad;
4580         char *addrp;
4581         u8 proto;
4582
4583         if (sk == NULL)
4584                 return NF_ACCEPT;
4585         sksec = sk->sk_security;
4586
4587         COMMON_AUDIT_DATA_INIT(&ad, NET);
4588         ad.u.net.netif = ifindex;
4589         ad.u.net.family = family;
4590         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4591                 return NF_DROP;
4592
4593         if (selinux_secmark_enabled())
4594                 if (avc_has_perm(sksec->sid, skb->secmark,
4595                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4596                         return NF_DROP_ERR(-ECONNREFUSED);
4597
4598         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4599                 return NF_DROP_ERR(-ECONNREFUSED);
4600
4601         return NF_ACCEPT;
4602 }
4603
4604 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4605                                          u16 family)
4606 {
4607         u32 secmark_perm;
4608         u32 peer_sid;
4609         struct sock *sk;
4610         struct common_audit_data ad;
4611         char *addrp;
4612         u8 secmark_active;
4613         u8 peerlbl_active;
4614
4615         /* If any sort of compatibility mode is enabled then handoff processing
4616          * to the selinux_ip_postroute_compat() function to deal with the
4617          * special handling.  We do this in an attempt to keep this function
4618          * as fast and as clean as possible. */
4619         if (!selinux_policycap_netpeer)
4620                 return selinux_ip_postroute_compat(skb, ifindex, family);
4621 #ifdef CONFIG_XFRM
4622         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4623          * packet transformation so allow the packet to pass without any checks
4624          * since we'll have another chance to perform access control checks
4625          * when the packet is on it's final way out.
4626          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4627          *       is NULL, in this case go ahead and apply access control. */
4628         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4629                 return NF_ACCEPT;
4630 #endif
4631         secmark_active = selinux_secmark_enabled();
4632         peerlbl_active = netlbl_enabled() || selinux_xfrm_enabled();
4633         if (!secmark_active && !peerlbl_active)
4634                 return NF_ACCEPT;
4635
4636         /* if the packet is being forwarded then get the peer label from the
4637          * packet itself; otherwise check to see if it is from a local
4638          * application or the kernel, if from an application get the peer label
4639          * from the sending socket, otherwise use the kernel's sid */
4640         sk = skb->sk;
4641         if (sk == NULL) {
4642                 if (skb->skb_iif) {
4643                         secmark_perm = PACKET__FORWARD_OUT;
4644                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4645                                 return NF_DROP;
4646                 } else {
4647                         secmark_perm = PACKET__SEND;
4648                         peer_sid = SECINITSID_KERNEL;
4649                 }
4650         } else {
4651                 struct sk_security_struct *sksec = sk->sk_security;
4652                 peer_sid = sksec->sid;
4653                 secmark_perm = PACKET__SEND;
4654         }
4655
4656         COMMON_AUDIT_DATA_INIT(&ad, NET);
4657         ad.u.net.netif = ifindex;
4658         ad.u.net.family = family;
4659         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4660                 return NF_DROP;
4661
4662         if (secmark_active)
4663                 if (avc_has_perm(peer_sid, skb->secmark,
4664                                  SECCLASS_PACKET, secmark_perm, &ad))
4665                         return NF_DROP_ERR(-ECONNREFUSED);
4666
4667         if (peerlbl_active) {
4668                 u32 if_sid;
4669                 u32 node_sid;
4670
4671                 if (sel_netif_sid(ifindex, &if_sid))
4672                         return NF_DROP;
4673                 if (avc_has_perm(peer_sid, if_sid,
4674                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4675                         return NF_DROP_ERR(-ECONNREFUSED);
4676
4677                 if (sel_netnode_sid(addrp, family, &node_sid))
4678                         return NF_DROP;
4679                 if (avc_has_perm(peer_sid, node_sid,
4680                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4681                         return NF_DROP_ERR(-ECONNREFUSED);
4682         }
4683
4684         return NF_ACCEPT;
4685 }
4686
4687 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4688                                            struct sk_buff *skb,
4689                                            const struct net_device *in,
4690                                            const struct net_device *out,
4691                                            int (*okfn)(struct sk_buff *))
4692 {
4693         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4694 }
4695
4696 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4697 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4698                                            struct sk_buff *skb,
4699                                            const struct net_device *in,
4700                                            const struct net_device *out,
4701                                            int (*okfn)(struct sk_buff *))
4702 {
4703         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4704 }
4705 #endif  /* IPV6 */
4706
4707 #endif  /* CONFIG_NETFILTER */
4708
4709 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4710 {
4711         int err;
4712
4713         err = cap_netlink_send(sk, skb);
4714         if (err)
4715                 return err;
4716
4717         return selinux_nlmsg_perm(sk, skb);
4718 }
4719
4720 static int selinux_netlink_recv(struct sk_buff *skb, int capability)
4721 {
4722         int err;
4723         struct common_audit_data ad;
4724         u32 sid;
4725
4726         err = cap_netlink_recv(skb, capability);
4727         if (err)
4728                 return err;
4729
4730         COMMON_AUDIT_DATA_INIT(&ad, CAP);
4731         ad.u.cap = capability;
4732
4733         security_task_getsecid(current, &sid);
4734         return avc_has_perm(sid, sid, SECCLASS_CAPABILITY,
4735                             CAP_TO_MASK(capability), &ad);
4736 }
4737
4738 static int ipc_alloc_security(struct task_struct *task,
4739                               struct kern_ipc_perm *perm,
4740                               u16 sclass)
4741 {
4742         struct ipc_security_struct *isec;
4743         u32 sid;
4744
4745         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4746         if (!isec)
4747                 return -ENOMEM;
4748
4749         sid = task_sid(task);
4750         isec->sclass = sclass;
4751         isec->sid = sid;
4752         perm->security = isec;
4753
4754         return 0;
4755 }
4756
4757 static void ipc_free_security(struct kern_ipc_perm *perm)
4758 {
4759         struct ipc_security_struct *isec = perm->security;
4760         perm->security = NULL;
4761         kfree(isec);
4762 }
4763
4764 static int msg_msg_alloc_security(struct msg_msg *msg)
4765 {
4766         struct msg_security_struct *msec;
4767
4768         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4769         if (!msec)
4770                 return -ENOMEM;
4771
4772         msec->sid = SECINITSID_UNLABELED;
4773         msg->security = msec;
4774
4775         return 0;
4776 }
4777
4778 static void msg_msg_free_security(struct msg_msg *msg)
4779 {
4780         struct msg_security_struct *msec = msg->security;
4781
4782         msg->security = NULL;
4783         kfree(msec);
4784 }
4785
4786 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4787                         u32 perms)
4788 {
4789         struct ipc_security_struct *isec;
4790         struct common_audit_data ad;
4791         u32 sid = current_sid();
4792
4793         isec = ipc_perms->security;
4794
4795         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4796         ad.u.ipc_id = ipc_perms->key;
4797
4798         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4799 }
4800
4801 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4802 {
4803         return msg_msg_alloc_security(msg);
4804 }
4805
4806 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4807 {
4808         msg_msg_free_security(msg);
4809 }
4810
4811 /* message queue security operations */
4812 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4813 {
4814         struct ipc_security_struct *isec;
4815         struct common_audit_data ad;
4816         u32 sid = current_sid();
4817         int rc;
4818
4819         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4820         if (rc)
4821                 return rc;
4822
4823         isec = msq->q_perm.security;
4824
4825         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4826         ad.u.ipc_id = msq->q_perm.key;
4827
4828         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4829                           MSGQ__CREATE, &ad);
4830         if (rc) {
4831                 ipc_free_security(&msq->q_perm);
4832                 return rc;
4833         }
4834         return 0;
4835 }
4836
4837 static void selinux_msg_queue_free_security(struct msg_queue *msq)
4838 {
4839         ipc_free_security(&msq->q_perm);
4840 }
4841
4842 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
4843 {
4844         struct ipc_security_struct *isec;
4845         struct common_audit_data ad;
4846         u32 sid = current_sid();
4847
4848         isec = msq->q_perm.security;
4849
4850         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4851         ad.u.ipc_id = msq->q_perm.key;
4852
4853         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4854                             MSGQ__ASSOCIATE, &ad);
4855 }
4856
4857 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
4858 {
4859         int err;
4860         int perms;
4861
4862         switch (cmd) {
4863         case IPC_INFO:
4864         case MSG_INFO:
4865                 /* No specific object, just general system-wide information. */
4866                 return task_has_system(current, SYSTEM__IPC_INFO);
4867         case IPC_STAT:
4868         case MSG_STAT:
4869                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
4870                 break;
4871         case IPC_SET:
4872                 perms = MSGQ__SETATTR;
4873                 break;
4874         case IPC_RMID:
4875                 perms = MSGQ__DESTROY;
4876                 break;
4877         default:
4878                 return 0;
4879         }
4880
4881         err = ipc_has_perm(&msq->q_perm, perms);
4882         return err;
4883 }
4884
4885 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
4886 {
4887         struct ipc_security_struct *isec;
4888         struct msg_security_struct *msec;
4889         struct common_audit_data ad;
4890         u32 sid = current_sid();
4891         int rc;
4892
4893         isec = msq->q_perm.security;
4894         msec = msg->security;
4895
4896         /*
4897          * First time through, need to assign label to the message
4898          */
4899         if (msec->sid == SECINITSID_UNLABELED) {
4900                 /*
4901                  * Compute new sid based on current process and
4902                  * message queue this message will be stored in
4903                  */
4904                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
4905                                              NULL, &msec->sid);
4906                 if (rc)
4907                         return rc;
4908         }
4909
4910         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4911         ad.u.ipc_id = msq->q_perm.key;
4912
4913         /* Can this process write to the queue? */
4914         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
4915                           MSGQ__WRITE, &ad);
4916         if (!rc)
4917                 /* Can this process send the message */
4918                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
4919                                   MSG__SEND, &ad);
4920         if (!rc)
4921                 /* Can the message be put in the queue? */
4922                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
4923                                   MSGQ__ENQUEUE, &ad);
4924
4925         return rc;
4926 }
4927
4928 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
4929                                     struct task_struct *target,
4930                                     long type, int mode)
4931 {
4932         struct ipc_security_struct *isec;
4933         struct msg_security_struct *msec;
4934         struct common_audit_data ad;
4935         u32 sid = task_sid(target);
4936         int rc;
4937
4938         isec = msq->q_perm.security;
4939         msec = msg->security;
4940
4941         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4942         ad.u.ipc_id = msq->q_perm.key;
4943
4944         rc = avc_has_perm(sid, isec->sid,
4945                           SECCLASS_MSGQ, MSGQ__READ, &ad);
4946         if (!rc)
4947                 rc = avc_has_perm(sid, msec->sid,
4948                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
4949         return rc;
4950 }
4951
4952 /* Shared Memory security operations */
4953 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
4954 {
4955         struct ipc_security_struct *isec;
4956         struct common_audit_data ad;
4957         u32 sid = current_sid();
4958         int rc;
4959
4960         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
4961         if (rc)
4962                 return rc;
4963
4964         isec = shp->shm_perm.security;
4965
4966         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4967         ad.u.ipc_id = shp->shm_perm.key;
4968
4969         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4970                           SHM__CREATE, &ad);
4971         if (rc) {
4972                 ipc_free_security(&shp->shm_perm);
4973                 return rc;
4974         }
4975         return 0;
4976 }
4977
4978 static void selinux_shm_free_security(struct shmid_kernel *shp)
4979 {
4980         ipc_free_security(&shp->shm_perm);
4981 }
4982
4983 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
4984 {
4985         struct ipc_security_struct *isec;
4986         struct common_audit_data ad;
4987         u32 sid = current_sid();
4988
4989         isec = shp->shm_perm.security;
4990
4991         COMMON_AUDIT_DATA_INIT(&ad, IPC);
4992         ad.u.ipc_id = shp->shm_perm.key;
4993
4994         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
4995                             SHM__ASSOCIATE, &ad);
4996 }
4997
4998 /* Note, at this point, shp is locked down */
4999 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5000 {
5001         int perms;
5002         int err;
5003
5004         switch (cmd) {
5005         case IPC_INFO:
5006         case SHM_INFO:
5007                 /* No specific object, just general system-wide information. */
5008                 return task_has_system(current, SYSTEM__IPC_INFO);
5009         case IPC_STAT:
5010         case SHM_STAT:
5011                 perms = SHM__GETATTR | SHM__ASSOCIATE;
5012                 break;
5013         case IPC_SET:
5014                 perms = SHM__SETATTR;
5015                 break;
5016         case SHM_LOCK:
5017         case SHM_UNLOCK:
5018                 perms = SHM__LOCK;
5019                 break;
5020         case IPC_RMID:
5021                 perms = SHM__DESTROY;
5022                 break;
5023         default:
5024                 return 0;
5025         }
5026
5027         err = ipc_has_perm(&shp->shm_perm, perms);
5028         return err;
5029 }
5030
5031 static int selinux_shm_shmat(struct shmid_kernel *shp,
5032                              char __user *shmaddr, int shmflg)
5033 {
5034         u32 perms;
5035
5036         if (shmflg & SHM_RDONLY)
5037                 perms = SHM__READ;
5038         else
5039                 perms = SHM__READ | SHM__WRITE;
5040
5041         return ipc_has_perm(&shp->shm_perm, perms);
5042 }
5043
5044 /* Semaphore security operations */
5045 static int selinux_sem_alloc_security(struct sem_array *sma)
5046 {
5047         struct ipc_security_struct *isec;
5048         struct common_audit_data ad;
5049         u32 sid = current_sid();
5050         int rc;
5051
5052         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5053         if (rc)
5054                 return rc;
5055
5056         isec = sma->sem_perm.security;
5057
5058         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5059         ad.u.ipc_id = sma->sem_perm.key;
5060
5061         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5062                           SEM__CREATE, &ad);
5063         if (rc) {
5064                 ipc_free_security(&sma->sem_perm);
5065                 return rc;
5066         }
5067         return 0;
5068 }
5069
5070 static void selinux_sem_free_security(struct sem_array *sma)
5071 {
5072         ipc_free_security(&sma->sem_perm);
5073 }
5074
5075 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5076 {
5077         struct ipc_security_struct *isec;
5078         struct common_audit_data ad;
5079         u32 sid = current_sid();
5080
5081         isec = sma->sem_perm.security;
5082
5083         COMMON_AUDIT_DATA_INIT(&ad, IPC);
5084         ad.u.ipc_id = sma->sem_perm.key;
5085
5086         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5087                             SEM__ASSOCIATE, &ad);
5088 }
5089
5090 /* Note, at this point, sma is locked down */
5091 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5092 {
5093         int err;
5094         u32 perms;
5095
5096         switch (cmd) {
5097         case IPC_INFO:
5098         case SEM_INFO:
5099                 /* No specific object, just general system-wide information. */
5100                 return task_has_system(current, SYSTEM__IPC_INFO);
5101         case GETPID:
5102         case GETNCNT:
5103         case GETZCNT:
5104                 perms = SEM__GETATTR;
5105                 break;
5106         case GETVAL:
5107         case GETALL:
5108                 perms = SEM__READ;
5109                 break;
5110         case SETVAL:
5111         case SETALL:
5112                 perms = SEM__WRITE;
5113                 break;
5114         case IPC_RMID:
5115                 perms = SEM__DESTROY;
5116                 break;
5117         case IPC_SET:
5118                 perms = SEM__SETATTR;
5119                 break;
5120         case IPC_STAT:
5121         case SEM_STAT:
5122                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5123                 break;
5124         default:
5125                 return 0;
5126         }
5127
5128         err = ipc_has_perm(&sma->sem_perm, perms);
5129         return err;
5130 }
5131
5132 static int selinux_sem_semop(struct sem_array *sma,
5133                              struct sembuf *sops, unsigned nsops, int alter)
5134 {
5135         u32 perms;
5136
5137         if (alter)
5138                 perms = SEM__READ | SEM__WRITE;
5139         else
5140                 perms = SEM__READ;
5141
5142         return ipc_has_perm(&sma->sem_perm, perms);
5143 }
5144
5145 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5146 {
5147         u32 av = 0;
5148
5149         av = 0;
5150         if (flag & S_IRUGO)
5151                 av |= IPC__UNIX_READ;
5152         if (flag & S_IWUGO)
5153                 av |= IPC__UNIX_WRITE;
5154
5155         if (av == 0)
5156                 return 0;
5157
5158         return ipc_has_perm(ipcp, av);
5159 }
5160
5161 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5162 {
5163         struct ipc_security_struct *isec = ipcp->security;
5164         *secid = isec->sid;
5165 }
5166
5167 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5168 {
5169         if (inode)
5170                 inode_doinit_with_dentry(inode, dentry);
5171 }
5172
5173 static int selinux_getprocattr(struct task_struct *p,
5174                                char *name, char **value)
5175 {
5176         const struct task_security_struct *__tsec;
5177         u32 sid;
5178         int error;
5179         unsigned len;
5180
5181         if (current != p) {
5182                 error = current_has_perm(p, PROCESS__GETATTR);
5183                 if (error)
5184                         return error;
5185         }
5186
5187         rcu_read_lock();
5188         __tsec = __task_cred(p)->security;
5189
5190         if (!strcmp(name, "current"))
5191                 sid = __tsec->sid;
5192         else if (!strcmp(name, "prev"))
5193                 sid = __tsec->osid;
5194         else if (!strcmp(name, "exec"))
5195                 sid = __tsec->exec_sid;
5196         else if (!strcmp(name, "fscreate"))
5197                 sid = __tsec->create_sid;
5198         else if (!strcmp(name, "keycreate"))
5199                 sid = __tsec->keycreate_sid;
5200         else if (!strcmp(name, "sockcreate"))
5201                 sid = __tsec->sockcreate_sid;
5202         else
5203                 goto invalid;
5204         rcu_read_unlock();
5205
5206         if (!sid)
5207                 return 0;
5208
5209         error = security_sid_to_context(sid, value, &len);
5210         if (error)
5211                 return error;
5212         return len;
5213
5214 invalid:
5215         rcu_read_unlock();
5216         return -EINVAL;
5217 }
5218
5219 static int selinux_setprocattr(struct task_struct *p,
5220                                char *name, void *value, size_t size)
5221 {
5222         struct task_security_struct *tsec;
5223         struct task_struct *tracer;
5224         struct cred *new;
5225         u32 sid = 0, ptsid;
5226         int error;
5227         char *str = value;
5228
5229         if (current != p) {
5230                 /* SELinux only allows a process to change its own
5231                    security attributes. */
5232                 return -EACCES;
5233         }
5234
5235         /*
5236          * Basic control over ability to set these attributes at all.
5237          * current == p, but we'll pass them separately in case the
5238          * above restriction is ever removed.
5239          */
5240         if (!strcmp(name, "exec"))
5241                 error = current_has_perm(p, PROCESS__SETEXEC);
5242         else if (!strcmp(name, "fscreate"))
5243                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5244         else if (!strcmp(name, "keycreate"))
5245                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5246         else if (!strcmp(name, "sockcreate"))
5247                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5248         else if (!strcmp(name, "current"))
5249                 error = current_has_perm(p, PROCESS__SETCURRENT);
5250         else
5251                 error = -EINVAL;
5252         if (error)
5253                 return error;
5254
5255         /* Obtain a SID for the context, if one was specified. */
5256         if (size && str[1] && str[1] != '\n') {
5257                 if (str[size-1] == '\n') {
5258                         str[size-1] = 0;
5259                         size--;
5260                 }
5261                 error = security_context_to_sid(value, size, &sid);
5262                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5263                         if (!capable(CAP_MAC_ADMIN))
5264                                 return error;
5265                         error = security_context_to_sid_force(value, size,
5266                                                               &sid);
5267                 }
5268                 if (error)
5269                         return error;
5270         }
5271
5272         new = prepare_creds();
5273         if (!new)
5274                 return -ENOMEM;
5275
5276         /* Permission checking based on the specified context is
5277            performed during the actual operation (execve,
5278            open/mkdir/...), when we know the full context of the
5279            operation.  See selinux_bprm_set_creds for the execve
5280            checks and may_create for the file creation checks. The
5281            operation will then fail if the context is not permitted. */
5282         tsec = new->security;
5283         if (!strcmp(name, "exec")) {
5284                 tsec->exec_sid = sid;
5285         } else if (!strcmp(name, "fscreate")) {
5286                 tsec->create_sid = sid;
5287         } else if (!strcmp(name, "keycreate")) {
5288                 error = may_create_key(sid, p);
5289                 if (error)
5290                         goto abort_change;
5291                 tsec->keycreate_sid = sid;
5292         } else if (!strcmp(name, "sockcreate")) {
5293                 tsec->sockcreate_sid = sid;
5294         } else if (!strcmp(name, "current")) {
5295                 error = -EINVAL;
5296                 if (sid == 0)
5297                         goto abort_change;
5298
5299                 /* Only allow single threaded processes to change context */
5300                 error = -EPERM;
5301                 if (!current_is_single_threaded()) {
5302                         error = security_bounded_transition(tsec->sid, sid);
5303                         if (error)
5304                                 goto abort_change;
5305                 }
5306
5307                 /* Check permissions for the transition. */
5308                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5309                                      PROCESS__DYNTRANSITION, NULL);
5310                 if (error)
5311                         goto abort_change;
5312
5313                 /* Check for ptracing, and update the task SID if ok.
5314                    Otherwise, leave SID unchanged and fail. */
5315                 ptsid = 0;
5316                 task_lock(p);
5317                 tracer = tracehook_tracer_task(p);
5318                 if (tracer)
5319                         ptsid = task_sid(tracer);
5320                 task_unlock(p);
5321
5322                 if (tracer) {
5323                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5324                                              PROCESS__PTRACE, NULL);
5325                         if (error)
5326                                 goto abort_change;
5327                 }
5328
5329                 tsec->sid = sid;
5330         } else {
5331                 error = -EINVAL;
5332                 goto abort_change;
5333         }
5334
5335         commit_creds(new);
5336         return size;
5337
5338 abort_change:
5339         abort_creds(new);
5340         return error;
5341 }
5342
5343 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5344 {
5345         return security_sid_to_context(secid, secdata, seclen);
5346 }
5347
5348 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5349 {
5350         return security_context_to_sid(secdata, seclen, secid);
5351 }
5352
5353 static void selinux_release_secctx(char *secdata, u32 seclen)
5354 {
5355         kfree(secdata);
5356 }
5357
5358 /*
5359  *      called with inode->i_mutex locked
5360  */
5361 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5362 {
5363         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5364 }
5365
5366 /*
5367  *      called with inode->i_mutex locked
5368  */
5369 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5370 {
5371         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5372 }
5373
5374 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5375 {
5376         int len = 0;
5377         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5378                                                 ctx, true);
5379         if (len < 0)
5380                 return len;
5381         *ctxlen = len;
5382         return 0;
5383 }
5384 #ifdef CONFIG_KEYS
5385
5386 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5387                              unsigned long flags)
5388 {
5389         const struct task_security_struct *tsec;
5390         struct key_security_struct *ksec;
5391
5392         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5393         if (!ksec)
5394                 return -ENOMEM;
5395
5396         tsec = cred->security;
5397         if (tsec->keycreate_sid)
5398                 ksec->sid = tsec->keycreate_sid;
5399         else
5400                 ksec->sid = tsec->sid;
5401
5402         k->security = ksec;
5403         return 0;
5404 }
5405
5406 static void selinux_key_free(struct key *k)
5407 {
5408         struct key_security_struct *ksec = k->security;
5409
5410         k->security = NULL;
5411         kfree(ksec);
5412 }
5413
5414 static int selinux_key_permission(key_ref_t key_ref,
5415                                   const struct cred *cred,
5416                                   key_perm_t perm)
5417 {
5418         struct key *key;
5419         struct key_security_struct *ksec;
5420         u32 sid;
5421
5422         /* if no specific permissions are requested, we skip the
5423            permission check. No serious, additional covert channels
5424            appear to be created. */
5425         if (perm == 0)
5426                 return 0;
5427
5428         sid = cred_sid(cred);
5429
5430         key = key_ref_to_ptr(key_ref);
5431         ksec = key->security;
5432
5433         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5434 }
5435
5436 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5437 {
5438         struct key_security_struct *ksec = key->security;
5439         char *context = NULL;
5440         unsigned len;
5441         int rc;
5442
5443         rc = security_sid_to_context(ksec->sid, &context, &len);
5444         if (!rc)
5445                 rc = len;
5446         *_buffer = context;
5447         return rc;
5448 }
5449
5450 #endif
5451
5452 static struct security_operations selinux_ops = {
5453         .name =                         "selinux",
5454
5455         .ptrace_access_check =          selinux_ptrace_access_check,
5456         .ptrace_traceme =               selinux_ptrace_traceme,
5457         .capget =                       selinux_capget,
5458         .capset =                       selinux_capset,
5459         .capable =                      selinux_capable,
5460         .quotactl =                     selinux_quotactl,
5461         .quota_on =                     selinux_quota_on,
5462         .syslog =                       selinux_syslog,
5463         .vm_enough_memory =             selinux_vm_enough_memory,
5464
5465         .netlink_send =                 selinux_netlink_send,
5466         .netlink_recv =                 selinux_netlink_recv,
5467
5468         .bprm_set_creds =               selinux_bprm_set_creds,
5469         .bprm_committing_creds =        selinux_bprm_committing_creds,
5470         .bprm_committed_creds =         selinux_bprm_committed_creds,
5471         .bprm_secureexec =              selinux_bprm_secureexec,
5472
5473         .sb_alloc_security =            selinux_sb_alloc_security,
5474         .sb_free_security =             selinux_sb_free_security,
5475         .sb_copy_data =                 selinux_sb_copy_data,
5476         .sb_remount =                   selinux_sb_remount,
5477         .sb_kern_mount =                selinux_sb_kern_mount,
5478         .sb_show_options =              selinux_sb_show_options,
5479         .sb_statfs =                    selinux_sb_statfs,
5480         .sb_mount =                     selinux_mount,
5481         .sb_umount =                    selinux_umount,
5482         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5483         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5484         .sb_parse_opts_str =            selinux_parse_opts_str,
5485
5486
5487         .inode_alloc_security =         selinux_inode_alloc_security,
5488         .inode_free_security =          selinux_inode_free_security,
5489         .inode_init_security =          selinux_inode_init_security,
5490         .inode_create =                 selinux_inode_create,
5491         .inode_link =                   selinux_inode_link,
5492         .inode_unlink =                 selinux_inode_unlink,
5493         .inode_symlink =                selinux_inode_symlink,
5494         .inode_mkdir =                  selinux_inode_mkdir,
5495         .inode_rmdir =                  selinux_inode_rmdir,
5496         .inode_mknod =                  selinux_inode_mknod,
5497         .inode_rename =                 selinux_inode_rename,
5498         .inode_readlink =               selinux_inode_readlink,
5499         .inode_follow_link =            selinux_inode_follow_link,
5500         .inode_permission =             selinux_inode_permission,
5501         .inode_setattr =                selinux_inode_setattr,
5502         .inode_getattr =                selinux_inode_getattr,
5503         .inode_setxattr =               selinux_inode_setxattr,
5504         .inode_post_setxattr =          selinux_inode_post_setxattr,
5505         .inode_getxattr =               selinux_inode_getxattr,
5506         .inode_listxattr =              selinux_inode_listxattr,
5507         .inode_removexattr =            selinux_inode_removexattr,
5508         .inode_getsecurity =            selinux_inode_getsecurity,
5509         .inode_setsecurity =            selinux_inode_setsecurity,
5510         .inode_listsecurity =           selinux_inode_listsecurity,
5511         .inode_getsecid =               selinux_inode_getsecid,
5512
5513         .file_permission =              selinux_file_permission,
5514         .file_alloc_security =          selinux_file_alloc_security,
5515         .file_free_security =           selinux_file_free_security,
5516         .file_ioctl =                   selinux_file_ioctl,
5517         .file_mmap =                    selinux_file_mmap,
5518         .file_mprotect =                selinux_file_mprotect,
5519         .file_lock =                    selinux_file_lock,
5520         .file_fcntl =                   selinux_file_fcntl,
5521         .file_set_fowner =              selinux_file_set_fowner,
5522         .file_send_sigiotask =          selinux_file_send_sigiotask,
5523         .file_receive =                 selinux_file_receive,
5524
5525         .dentry_open =                  selinux_dentry_open,
5526
5527         .task_create =                  selinux_task_create,
5528         .cred_alloc_blank =             selinux_cred_alloc_blank,
5529         .cred_free =                    selinux_cred_free,
5530         .cred_prepare =                 selinux_cred_prepare,
5531         .cred_transfer =                selinux_cred_transfer,
5532         .kernel_act_as =                selinux_kernel_act_as,
5533         .kernel_create_files_as =       selinux_kernel_create_files_as,
5534         .kernel_module_request =        selinux_kernel_module_request,
5535         .task_setpgid =                 selinux_task_setpgid,
5536         .task_getpgid =                 selinux_task_getpgid,
5537         .task_getsid =                  selinux_task_getsid,
5538         .task_getsecid =                selinux_task_getsecid,
5539         .task_setnice =                 selinux_task_setnice,
5540         .task_setioprio =               selinux_task_setioprio,
5541         .task_getioprio =               selinux_task_getioprio,
5542         .task_setrlimit =               selinux_task_setrlimit,
5543         .task_setscheduler =            selinux_task_setscheduler,
5544         .task_getscheduler =            selinux_task_getscheduler,
5545         .task_movememory =              selinux_task_movememory,
5546         .task_kill =                    selinux_task_kill,
5547         .task_wait =                    selinux_task_wait,
5548         .task_to_inode =                selinux_task_to_inode,
5549
5550         .ipc_permission =               selinux_ipc_permission,
5551         .ipc_getsecid =                 selinux_ipc_getsecid,
5552
5553         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5554         .msg_msg_free_security =        selinux_msg_msg_free_security,
5555
5556         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5557         .msg_queue_free_security =      selinux_msg_queue_free_security,
5558         .msg_queue_associate =          selinux_msg_queue_associate,
5559         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5560         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5561         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5562
5563         .shm_alloc_security =           selinux_shm_alloc_security,
5564         .shm_free_security =            selinux_shm_free_security,
5565         .shm_associate =                selinux_shm_associate,
5566         .shm_shmctl =                   selinux_shm_shmctl,
5567         .shm_shmat =                    selinux_shm_shmat,
5568
5569         .sem_alloc_security =           selinux_sem_alloc_security,
5570         .sem_free_security =            selinux_sem_free_security,
5571         .sem_associate =                selinux_sem_associate,
5572         .sem_semctl =                   selinux_sem_semctl,
5573         .sem_semop =                    selinux_sem_semop,
5574
5575         .d_instantiate =                selinux_d_instantiate,
5576
5577         .getprocattr =                  selinux_getprocattr,
5578         .setprocattr =                  selinux_setprocattr,
5579
5580         .secid_to_secctx =              selinux_secid_to_secctx,
5581         .secctx_to_secid =              selinux_secctx_to_secid,
5582         .release_secctx =               selinux_release_secctx,
5583         .inode_notifysecctx =           selinux_inode_notifysecctx,
5584         .inode_setsecctx =              selinux_inode_setsecctx,
5585         .inode_getsecctx =              selinux_inode_getsecctx,
5586
5587         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5588         .unix_may_send =                selinux_socket_unix_may_send,
5589
5590         .socket_create =                selinux_socket_create,
5591         .socket_post_create =           selinux_socket_post_create,
5592         .socket_bind =                  selinux_socket_bind,
5593         .socket_connect =               selinux_socket_connect,
5594         .socket_listen =                selinux_socket_listen,
5595         .socket_accept =                selinux_socket_accept,
5596         .socket_sendmsg =               selinux_socket_sendmsg,
5597         .socket_recvmsg =               selinux_socket_recvmsg,
5598         .socket_getsockname =           selinux_socket_getsockname,
5599         .socket_getpeername =           selinux_socket_getpeername,
5600         .socket_getsockopt =            selinux_socket_getsockopt,
5601         .socket_setsockopt =            selinux_socket_setsockopt,
5602         .socket_shutdown =              selinux_socket_shutdown,
5603         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5604         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5605         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5606         .sk_alloc_security =            selinux_sk_alloc_security,
5607         .sk_free_security =             selinux_sk_free_security,
5608         .sk_clone_security =            selinux_sk_clone_security,
5609         .sk_getsecid =                  selinux_sk_getsecid,
5610         .sock_graft =                   selinux_sock_graft,
5611         .inet_conn_request =            selinux_inet_conn_request,
5612         .inet_csk_clone =               selinux_inet_csk_clone,
5613         .inet_conn_established =        selinux_inet_conn_established,
5614         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
5615         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
5616         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
5617         .req_classify_flow =            selinux_req_classify_flow,
5618         .tun_dev_create =               selinux_tun_dev_create,
5619         .tun_dev_post_create =          selinux_tun_dev_post_create,
5620         .tun_dev_attach =               selinux_tun_dev_attach,
5621
5622 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5623         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5624         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5625         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5626         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5627         .xfrm_state_alloc_security =    selinux_xfrm_state_alloc,
5628         .xfrm_state_free_security =     selinux_xfrm_state_free,
5629         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5630         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5631         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5632         .xfrm_decode_session =          selinux_xfrm_decode_session,
5633 #endif
5634
5635 #ifdef CONFIG_KEYS
5636         .key_alloc =                    selinux_key_alloc,
5637         .key_free =                     selinux_key_free,
5638         .key_permission =               selinux_key_permission,
5639         .key_getsecurity =              selinux_key_getsecurity,
5640 #endif
5641
5642 #ifdef CONFIG_AUDIT
5643         .audit_rule_init =              selinux_audit_rule_init,
5644         .audit_rule_known =             selinux_audit_rule_known,
5645         .audit_rule_match =             selinux_audit_rule_match,
5646         .audit_rule_free =              selinux_audit_rule_free,
5647 #endif
5648 };
5649
5650 static __init int selinux_init(void)
5651 {
5652         if (!security_module_enable(&selinux_ops)) {
5653                 selinux_enabled = 0;
5654                 return 0;
5655         }
5656
5657         if (!selinux_enabled) {
5658                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5659                 return 0;
5660         }
5661
5662         printk(KERN_INFO "SELinux:  Initializing.\n");
5663
5664         /* Set the security state for the initial task. */
5665         cred_init_security();
5666
5667         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5668
5669         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5670                                             sizeof(struct inode_security_struct),
5671                                             0, SLAB_PANIC, NULL);
5672         avc_init();
5673
5674         if (register_security(&selinux_ops))
5675                 panic("SELinux: Unable to register with kernel.\n");
5676
5677         if (selinux_enforcing)
5678                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5679         else
5680                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5681
5682         return 0;
5683 }
5684
5685 static void delayed_superblock_init(struct super_block *sb, void *unused)
5686 {
5687         superblock_doinit(sb, NULL);
5688 }
5689
5690 void selinux_complete_init(void)
5691 {
5692         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5693
5694         /* Set up any superblocks initialized prior to the policy load. */
5695         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5696         iterate_supers(delayed_superblock_init, NULL);
5697 }
5698
5699 /* SELinux requires early initialization in order to label
5700    all processes and objects when they are created. */
5701 security_initcall(selinux_init);
5702
5703 #if defined(CONFIG_NETFILTER)
5704
5705 static struct nf_hook_ops selinux_ipv4_ops[] = {
5706         {
5707                 .hook =         selinux_ipv4_postroute,
5708                 .owner =        THIS_MODULE,
5709                 .pf =           PF_INET,
5710                 .hooknum =      NF_INET_POST_ROUTING,
5711                 .priority =     NF_IP_PRI_SELINUX_LAST,
5712         },
5713         {
5714                 .hook =         selinux_ipv4_forward,
5715                 .owner =        THIS_MODULE,
5716                 .pf =           PF_INET,
5717                 .hooknum =      NF_INET_FORWARD,
5718                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5719         },
5720         {
5721                 .hook =         selinux_ipv4_output,
5722                 .owner =        THIS_MODULE,
5723                 .pf =           PF_INET,
5724                 .hooknum =      NF_INET_LOCAL_OUT,
5725                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5726         }
5727 };
5728
5729 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5730
5731 static struct nf_hook_ops selinux_ipv6_ops[] = {
5732         {
5733                 .hook =         selinux_ipv6_postroute,
5734                 .owner =        THIS_MODULE,
5735                 .pf =           PF_INET6,
5736                 .hooknum =      NF_INET_POST_ROUTING,
5737                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5738         },
5739         {
5740                 .hook =         selinux_ipv6_forward,
5741                 .owner =        THIS_MODULE,
5742                 .pf =           PF_INET6,
5743                 .hooknum =      NF_INET_FORWARD,
5744                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5745         }
5746 };
5747
5748 #endif  /* IPV6 */
5749
5750 static int __init selinux_nf_ip_init(void)
5751 {
5752         int err = 0;
5753
5754         if (!selinux_enabled)
5755                 goto out;
5756
5757         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5758
5759         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5760         if (err)
5761                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5762
5763 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5764         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5765         if (err)
5766                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5767 #endif  /* IPV6 */
5768
5769 out:
5770         return err;
5771 }
5772
5773 __initcall(selinux_nf_ip_init);
5774
5775 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5776 static void selinux_nf_ip_exit(void)
5777 {
5778         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5779
5780         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5781 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5782         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5783 #endif  /* IPV6 */
5784 }
5785 #endif
5786
5787 #else /* CONFIG_NETFILTER */
5788
5789 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5790 #define selinux_nf_ip_exit()
5791 #endif
5792
5793 #endif /* CONFIG_NETFILTER */
5794
5795 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5796 static int selinux_disabled;
5797
5798 int selinux_disable(void)
5799 {
5800         extern void exit_sel_fs(void);
5801
5802         if (ss_initialized) {
5803                 /* Not permitted after initial policy load. */
5804                 return -EINVAL;
5805         }
5806
5807         if (selinux_disabled) {
5808                 /* Only do this once. */
5809                 return -EINVAL;
5810         }
5811
5812         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
5813
5814         selinux_disabled = 1;
5815         selinux_enabled = 0;
5816
5817         reset_security_ops();
5818
5819         /* Try to destroy the avc node cache */
5820         avc_disable();
5821
5822         /* Unregister netfilter hooks. */
5823         selinux_nf_ip_exit();
5824
5825         /* Unregister selinuxfs. */
5826         exit_sel_fs();
5827
5828         return 0;
5829 }
5830 #endif