security/selinux/hooks.c

   1 /*
   2  *  NSA Security-Enhanced Linux (SELinux) security module
   3  *
   4  *  This file contains the SELinux hook function implementations.
   5  *
   6  *  Authors:  Stephen Smalley, <sds@epoch.ncsc.mil>
   7  *            Chris Vance, <cvance@nai.com>
   8  *            Wayne Salamon, <wsalamon@nai.com>
   9  *            James Morris <jmorris@redhat.com>
  10  *
  11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <jmorris@redhat.com>
  13  *                                         Eric Paris <eparis@redhat.com>
  14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  15  *                          <dgoeddel@trustedcs.com>
  16  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
  17  *      Paul Moore <paul@paul-moore.com>
  18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  19  *                     Yuichi Nakamura <ynakam@hitachisoft.jp>
  20  *
  21  *      This program is free software; you can redistribute it and/or modify
  22  *      it under the terms of the GNU General Public License version 2,
  23  *      as published by the Free Software Foundation.
  24  */
  25
  26 #include <linux/init.h>
  27 #include <linux/kd.h>
  28 #include <linux/kernel.h>
  29 #include <linux/tracehook.h>
  30 #include <linux/errno.h>
  31 #include <linux/sched.h>
  32 #include <linux/security.h>
  33 #include <linux/xattr.h>
  34 #include <linux/capability.h>
  35 #include <linux/unistd.h>
  36 #include <linux/mm.h>
  37 #include <linux/mman.h>
  38 #include <linux/slab.h>
  39 #include <linux/pagemap.h>
  40 #include <linux/proc_fs.h>
  41 #include <linux/swap.h>
  42 #include <linux/spinlock.h>
  43 #include <linux/syscalls.h>
  44 #include <linux/dcache.h>
  45 #include <linux/file.h>
  46 #include <linux/fdtable.h>
  47 #include <linux/namei.h>
  48 #include <linux/mount.h>
  49 #include <linux/netfilter_ipv4.h>
  50 #include <linux/netfilter_ipv6.h>
  51 #include <linux/tty.h>
  52 #include <net/icmp.h>
  53 #include <net/ip.h>             /* for local_port_range[] */
  54 #include <net/sock.h>
  55 #include <net/tcp.h>            /* struct or_callable used in sock_rcv_skb */
  56 #include <net/net_namespace.h>
  57 #include <net/netlabel.h>
  58 #include <linux/uaccess.h>
  59 #include <asm/ioctls.h>
  60 #include <linux/atomic.h>
  61 #include <linux/bitops.h>
  62 #include <linux/interrupt.h>
  63 #include <linux/netdevice.h>    /* for network interface checks */
  64 #include <net/netlink.h>
  65 #include <linux/tcp.h>
  66 #include <linux/udp.h>
  67 #include <linux/dccp.h>
  68 #include <linux/quota.h>
  69 #include <linux/un.h>           /* for Unix socket types */
  70 #include <net/af_unix.h>        /* for Unix socket types */
  71 #include <linux/parser.h>
  72 #include <linux/nfs_mount.h>
  73 #include <net/ipv6.h>
  74 #include <linux/hugetlb.h>
  75 #include <linux/personality.h>
  76 #include <linux/audit.h>
  77 #include <linux/string.h>
  78 #include <linux/selinux.h>
  79 #include <linux/mutex.h>
  80 #include <linux/posix-timers.h>
  81 #include <linux/syslog.h>
  82 #include <linux/user_namespace.h>
  83 #include <linux/export.h>
  84 #include <linux/security.h>
  85 #include <linux/msg.h>
  86 #include <linux/shm.h>
  87
  88 #include "avc.h"
  89 #include "objsec.h"
  90 #include "netif.h"
  91 #include "netnode.h"
  92 #include "netport.h"
  93 #include "xfrm.h"
  94 #include "netlabel.h"
  95 #include "audit.h"
  96 #include "avc_ss.h"
  97
  98 #define SB_TYPE_FMT "%s%s%s"
  99 #define SB_SUBTYPE(sb) (sb->s_subtype && sb->s_subtype[0])
 100 #define SB_TYPE_ARGS(sb) sb->s_type->name, SB_SUBTYPE(sb) ? "." : "", SB_SUBTYPE(sb) ? sb->s_subtype : ""
 101
 102 extern struct security_operations *security_ops;
 103
 104 /* SECMARK reference count */
 105 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
 106
 107 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 108 int selinux_enforcing;
 109
 110 static int __init enforcing_setup(char *str)
 111 {
 112         unsigned long enforcing;
 113         if (!strict_strtoul(str, 0, &enforcing))
 114                 selinux_enforcing = enforcing ? 1 : 0;
 115         return 1;
 116 }
 117 __setup("enforcing=", enforcing_setup);
 118 #endif
 119
 120 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 121 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
 122
 123 static int __init selinux_enabled_setup(char *str)
 124 {
 125         unsigned long enabled;
 126         if (!strict_strtoul(str, 0, &enabled))
 127                 selinux_enabled = enabled ? 1 : 0;
 128         return 1;
 129 }
 130 __setup("selinux=", selinux_enabled_setup);
 131 #else
 132 int selinux_enabled = 1;
 133 #endif
 134
 135 static struct kmem_cache *sel_inode_cache;
 136
 137 /**
 138  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 139  *
 140  * Description:
 141  * This function checks the SECMARK reference counter to see if any SECMARK
 142  * targets are currently configured, if the reference counter is greater than
 143  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 144  * enabled, false (0) if SECMARK is disabled.  If the always_check_network
 145  * policy capability is enabled, SECMARK is always considered enabled.
 146  *
 147  */
 148 static int selinux_secmark_enabled(void)
 149 {
 150         return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount));
 151 }
 152
 153 /**
 154  * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
 155  *
 156  * Description:
 157  * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
 158  * (1) if any are enabled or false (0) if neither are enabled.  If the
 159  * always_check_network policy capability is enabled, peer labeling
 160  * is always considered enabled.
 161  *
 162  */
 163 static int selinux_peerlbl_enabled(void)
 164 {
 165         return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled());
 166 }
 167
 168 /*
 169  * initialise the security for the init task
 170  */
 171 static void cred_init_security(void)
 172 {
 173         struct cred *cred = (struct cred *) current->real_cred;
 174         struct task_security_struct *tsec;
 175
 176         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 177         if (!tsec)
 178                 panic("SELinux:  Failed to initialize initial task.\n");
 179
 180         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 181         cred->security = tsec;
 182 }
 183
 184 /*
 185  * get the security ID of a set of credentials
 186  */
 187 static inline u32 cred_sid(const struct cred *cred)
 188 {
 189         const struct task_security_struct *tsec;
 190
 191         tsec = cred->security;
 192         return tsec->sid;
 193 }
 194
 195 /*
 196  * get the objective security ID of a task
 197  */
 198 static inline u32 task_sid(const struct task_struct *task)
 199 {
 200         u32 sid;
 201
 202         rcu_read_lock();
 203         sid = cred_sid(__task_cred(task));
 204         rcu_read_unlock();
 205         return sid;
 206 }
 207
 208 /*
 209  * get the subjective security ID of the current task
 210  */
 211 static inline u32 current_sid(void)
 212 {
 213         const struct task_security_struct *tsec = current_security();
 214
 215         return tsec->sid;
 216 }
 217
 218 /* Allocate and free functions for each kind of security blob. */
 219
 220 static int inode_alloc_security(struct inode *inode)
 221 {
 222         struct inode_security_struct *isec;
 223         u32 sid = current_sid();
 224
 225         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
 226         if (!isec)
 227                 return -ENOMEM;
 228
 229         mutex_init(&isec->lock);
 230         INIT_LIST_HEAD(&isec->list);
 231         isec->inode = inode;
 232         isec->sid = SECINITSID_UNLABELED;
 233         isec->sclass = SECCLASS_FILE;
 234         isec->task_sid = sid;
 235         inode->i_security = isec;
 236
 237         return 0;
 238 }
 239
 240 static void inode_free_security(struct inode *inode)
 241 {
 242         struct inode_security_struct *isec = inode->i_security;
 243         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 244
 245         spin_lock(&sbsec->isec_lock);
 246         if (!list_empty(&isec->list))
 247                 list_del_init(&isec->list);
 248         spin_unlock(&sbsec->isec_lock);
 249
 250         inode->i_security = NULL;
 251         kmem_cache_free(sel_inode_cache, isec);
 252 }
 253
 254 static int file_alloc_security(struct file *file)
 255 {
 256         struct file_security_struct *fsec;
 257         u32 sid = current_sid();
 258
 259         fsec = kzalloc(sizeof(struct file_security_struct), GFP_KERNEL);
 260         if (!fsec)
 261                 return -ENOMEM;
 262
 263         fsec->sid = sid;
 264         fsec->fown_sid = sid;
 265         file->f_security = fsec;
 266
 267         return 0;
 268 }
 269
 270 static void file_free_security(struct file *file)
 271 {
 272         struct file_security_struct *fsec = file->f_security;
 273         file->f_security = NULL;
 274         kfree(fsec);
 275 }
 276
 277 static int superblock_alloc_security(struct super_block *sb)
 278 {
 279         struct superblock_security_struct *sbsec;
 280
 281         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 282         if (!sbsec)
 283                 return -ENOMEM;
 284
 285         mutex_init(&sbsec->lock);
 286         INIT_LIST_HEAD(&sbsec->isec_head);
 287         spin_lock_init(&sbsec->isec_lock);
 288         sbsec->sb = sb;
 289         sbsec->sid = SECINITSID_UNLABELED;
 290         sbsec->def_sid = SECINITSID_FILE;
 291         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 292         sb->s_security = sbsec;
 293
 294         return 0;
 295 }
 296
 297 static void superblock_free_security(struct super_block *sb)
 298 {
 299         struct superblock_security_struct *sbsec = sb->s_security;
 300         sb->s_security = NULL;
 301         kfree(sbsec);
 302 }
 303
 304 /* The file system's label must be initialized prior to use. */
 305
 306 static const char *labeling_behaviors[7] = {
 307         "uses xattr",
 308         "uses transition SIDs",
 309         "uses task SIDs",
 310         "uses genfs_contexts",
 311         "not configured for labeling",
 312         "uses mountpoint labeling",
 313         "uses native labeling",
 314 };
 315
 316 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 317
 318 static inline int inode_doinit(struct inode *inode)
 319 {
 320         return inode_doinit_with_dentry(inode, NULL);
 321 }
 322
 323 enum {
 324         Opt_error = -1,
 325         Opt_context = 1,
 326         Opt_fscontext = 2,
 327         Opt_defcontext = 3,
 328         Opt_rootcontext = 4,
 329         Opt_labelsupport = 5,
 330         Opt_nextmntopt = 6,
 331 };
 332
 333 #define NUM_SEL_MNT_OPTS        (Opt_nextmntopt - 1)
 334
 335 static const match_table_t tokens = {
 336         {Opt_context, CONTEXT_STR "%s"},
 337         {Opt_fscontext, FSCONTEXT_STR "%s"},
 338         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 339         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 340         {Opt_labelsupport, LABELSUPP_STR},
 341         {Opt_error, NULL},
 342 };
 343
 344 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 345
 346 static int may_context_mount_sb_relabel(u32 sid,
 347                         struct superblock_security_struct *sbsec,
 348                         const struct cred *cred)
 349 {
 350         const struct task_security_struct *tsec = cred->security;
 351         int rc;
 352
 353         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 354                           FILESYSTEM__RELABELFROM, NULL);
 355         if (rc)
 356                 return rc;
 357
 358         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 359                           FILESYSTEM__RELABELTO, NULL);
 360         return rc;
 361 }
 362
 363 static int may_context_mount_inode_relabel(u32 sid,
 364                         struct superblock_security_struct *sbsec,
 365                         const struct cred *cred)
 366 {
 367         const struct task_security_struct *tsec = cred->security;
 368         int rc;
 369         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 370                           FILESYSTEM__RELABELFROM, NULL);
 371         if (rc)
 372                 return rc;
 373
 374         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 375                           FILESYSTEM__ASSOCIATE, NULL);
 376         return rc;
 377 }
 378
 379 static int selinux_is_sblabel_mnt(struct super_block *sb)
 380 {
 381         struct superblock_security_struct *sbsec = sb->s_security;
 382
 383         if (sbsec->behavior == SECURITY_FS_USE_XATTR ||
 384             sbsec->behavior == SECURITY_FS_USE_TRANS ||
 385             sbsec->behavior == SECURITY_FS_USE_TASK)
 386                 return 1;
 387
 388         /* Special handling for sysfs. Is genfs but also has setxattr handler*/
 389         if (strncmp(sb->s_type->name, "sysfs", sizeof("sysfs")) == 0)
 390                 return 1;
 391
 392         /*
 393          * Special handling for rootfs. Is genfs but supports
 394          * setting SELinux context on in-core inodes.
 395          */
 396         if (strncmp(sb->s_type->name, "rootfs", sizeof("rootfs")) == 0)
 397                 return 1;
 398
 399         return 0;
 400 }
 401
 402 static int sb_finish_set_opts(struct super_block *sb)
 403 {
 404         struct superblock_security_struct *sbsec = sb->s_security;
 405         struct dentry *root = sb->s_root;
 406         struct inode *root_inode = root->d_inode;
 407         int rc = 0;
 408
 409         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 410                 /* Make sure that the xattr handler exists and that no
 411                    error other than -ENODATA is returned by getxattr on
 412                    the root directory.  -ENODATA is ok, as this may be
 413                    the first boot of the SELinux kernel before we have
 414                    assigned xattr values to the filesystem. */
 415                 if (!root_inode->i_op->getxattr) {
 416                         printk(KERN_WARNING "SELinux: (dev %s, type "SB_TYPE_FMT") has no "
 417                                "xattr support\n", sb->s_id, SB_TYPE_ARGS(sb));
 418                         rc = -EOPNOTSUPP;
 419                         goto out;
 420                 }
 421                 rc = root_inode->i_op->getxattr(root, XATTR_NAME_SELINUX, NULL, 0);
 422                 if (rc < 0 && rc != -ENODATA) {
 423                         if (rc == -EOPNOTSUPP)
 424                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 425                                        SB_TYPE_FMT") has no security xattr handler\n",
 426                                        sb->s_id, SB_TYPE_ARGS(sb));
 427                         else
 428                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 429                                        SB_TYPE_FMT") getxattr errno %d\n", sb->s_id,
 430                                        SB_TYPE_ARGS(sb), -rc);
 431                         goto out;
 432                 }
 433         }
 434
 435         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 436                 printk(KERN_ERR "SELinux: initialized (dev %s, type "SB_TYPE_FMT"), unknown behavior\n",
 437                        sb->s_id, SB_TYPE_ARGS(sb));
 438         else
 439                 printk(KERN_DEBUG "SELinux: initialized (dev %s, type "SB_TYPE_FMT"), %s\n",
 440                        sb->s_id, SB_TYPE_ARGS(sb),
 441                        labeling_behaviors[sbsec->behavior-1]);
 442
 443         sbsec->flags |= SE_SBINITIALIZED;
 444         if (selinux_is_sblabel_mnt(sb))
 445                 sbsec->flags |= SBLABEL_MNT;
 446
 447         /* Initialize the root inode. */
 448         rc = inode_doinit_with_dentry(root_inode, root);
 449
 450         /* Initialize any other inodes associated with the superblock, e.g.
 451            inodes created prior to initial policy load or inodes created
 452            during get_sb by a pseudo filesystem that directly
 453            populates itself. */
 454         spin_lock(&sbsec->isec_lock);
 455 next_inode:
 456         if (!list_empty(&sbsec->isec_head)) {
 457                 struct inode_security_struct *isec =
 458                                 list_entry(sbsec->isec_head.next,
 459                                            struct inode_security_struct, list);
 460                 struct inode *inode = isec->inode;
 461                 spin_unlock(&sbsec->isec_lock);
 462                 inode = igrab(inode);
 463                 if (inode) {
 464                         if (!IS_PRIVATE(inode))
 465                                 inode_doinit(inode);
 466                         iput(inode);
 467                 }
 468                 spin_lock(&sbsec->isec_lock);
 469                 list_del_init(&isec->list);
 470                 goto next_inode;
 471         }
 472         spin_unlock(&sbsec->isec_lock);
 473 out:
 474         return rc;
 475 }
 476
 477 /*
 478  * This function should allow an FS to ask what it's mount security
 479  * options were so it can use those later for submounts, displaying
 480  * mount options, or whatever.
 481  */
 482 static int selinux_get_mnt_opts(const struct super_block *sb,
 483                                 struct security_mnt_opts *opts)
 484 {
 485         int rc = 0, i;
 486         struct superblock_security_struct *sbsec = sb->s_security;
 487         char *context = NULL;
 488         u32 len;
 489         char tmp;
 490
 491         security_init_mnt_opts(opts);
 492
 493         if (!(sbsec->flags & SE_SBINITIALIZED))
 494                 return -EINVAL;
 495
 496         if (!ss_initialized)
 497                 return -EINVAL;
 498
 499         /* make sure we always check enough bits to cover the mask */
 500         BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));
 501
 502         tmp = sbsec->flags & SE_MNTMASK;
 503         /* count the number of mount options for this sb */
 504         for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
 505                 if (tmp & 0x01)
 506                         opts->num_mnt_opts++;
 507                 tmp >>= 1;
 508         }
 509         /* Check if the Label support flag is set */
 510         if (sbsec->flags & SBLABEL_MNT)
 511                 opts->num_mnt_opts++;
 512
 513         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 514         if (!opts->mnt_opts) {
 515                 rc = -ENOMEM;
 516                 goto out_free;
 517         }
 518
 519         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 520         if (!opts->mnt_opts_flags) {
 521                 rc = -ENOMEM;
 522                 goto out_free;
 523         }
 524
 525         i = 0;
 526         if (sbsec->flags & FSCONTEXT_MNT) {
 527                 rc = security_sid_to_context(sbsec->sid, &context, &len);
 528                 if (rc)
 529                         goto out_free;
 530                 opts->mnt_opts[i] = context;
 531                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 532         }
 533         if (sbsec->flags & CONTEXT_MNT) {
 534                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
 535                 if (rc)
 536                         goto out_free;
 537                 opts->mnt_opts[i] = context;
 538                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 539         }
 540         if (sbsec->flags & DEFCONTEXT_MNT) {
 541                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
 542                 if (rc)
 543                         goto out_free;
 544                 opts->mnt_opts[i] = context;
 545                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 546         }
 547         if (sbsec->flags & ROOTCONTEXT_MNT) {
 548                 struct inode *root = sbsec->sb->s_root->d_inode;
 549                 struct inode_security_struct *isec = root->i_security;
 550
 551                 rc = security_sid_to_context(isec->sid, &context, &len);
 552                 if (rc)
 553                         goto out_free;
 554                 opts->mnt_opts[i] = context;
 555                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 556         }
 557         if (sbsec->flags & SBLABEL_MNT) {
 558                 opts->mnt_opts[i] = NULL;
 559                 opts->mnt_opts_flags[i++] = SBLABEL_MNT;
 560         }
 561
 562         BUG_ON(i != opts->num_mnt_opts);
 563
 564         return 0;
 565
 566 out_free:
 567         security_free_mnt_opts(opts);
 568         return rc;
 569 }
 570
 571 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 572                       u32 old_sid, u32 new_sid)
 573 {
 574         char mnt_flags = sbsec->flags & SE_MNTMASK;
 575
 576         /* check if the old mount command had the same options */
 577         if (sbsec->flags & SE_SBINITIALIZED)
 578                 if (!(sbsec->flags & flag) ||
 579                     (old_sid != new_sid))
 580                         return 1;
 581
 582         /* check if we were passed the same options twice,
 583          * aka someone passed context=a,context=b
 584          */
 585         if (!(sbsec->flags & SE_SBINITIALIZED))
 586                 if (mnt_flags & flag)
 587                         return 1;
 588         return 0;
 589 }
 590
 591 /*
 592  * Allow filesystems with binary mount data to explicitly set mount point
 593  * labeling information.
 594  */
 595 static int selinux_set_mnt_opts(struct super_block *sb,
 596                                 struct security_mnt_opts *opts,
 597                                 unsigned long kern_flags,
 598                                 unsigned long *set_kern_flags)
 599 {
 600         const struct cred *cred = current_cred();
 601         int rc = 0, i;
 602         struct superblock_security_struct *sbsec = sb->s_security;
 603         struct inode *inode = sbsec->sb->s_root->d_inode;
 604         struct inode_security_struct *root_isec = inode->i_security;
 605         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 606         u32 defcontext_sid = 0;
 607         char **mount_options = opts->mnt_opts;
 608         int *flags = opts->mnt_opts_flags;
 609         int num_opts = opts->num_mnt_opts;
 610
 611         mutex_lock(&sbsec->lock);
 612
 613         if (!ss_initialized) {
 614                 if (!num_opts) {
 615                         /* Defer initialization until selinux_complete_init,
 616                            after the initial policy is loaded and the security
 617                            server is ready to handle calls. */
 618                         goto out;
 619                 }
 620                 rc = -EINVAL;
 621                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
 622                         "before the security server is initialized\n");
 623                 goto out;
 624         }
 625         if (kern_flags && !set_kern_flags) {
 626                 /* Specifying internal flags without providing a place to
 627                  * place the results is not allowed */
 628                 rc = -EINVAL;
 629                 goto out;
 630         }
 631
 632         /*
 633          * Binary mount data FS will come through this function twice.  Once
 634          * from an explicit call and once from the generic calls from the vfs.
 635          * Since the generic VFS calls will not contain any security mount data
 636          * we need to skip the double mount verification.
 637          *
 638          * This does open a hole in which we will not notice if the first
 639          * mount using this sb set explict options and a second mount using
 640          * this sb does not set any security options.  (The first options
 641          * will be used for both mounts)
 642          */
 643         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 644             && (num_opts == 0))
 645                 goto out;
 646
 647         /*
 648          * parse the mount options, check if they are valid sids.
 649          * also check if someone is trying to mount the same sb more
 650          * than once with different security options.
 651          */
 652         for (i = 0; i < num_opts; i++) {
 653                 u32 sid;
 654
 655                 if (flags[i] == SBLABEL_MNT)
 656                         continue;
 657                 rc = security_context_to_sid(mount_options[i],
 658                                              strlen(mount_options[i]), &sid);
 659                 if (rc) {
 660                         printk(KERN_WARNING "SELinux: security_context_to_sid"
 661                                "(%s) failed for (dev %s, type "SB_TYPE_FMT") errno=%d\n",
 662                                mount_options[i], sb->s_id, SB_TYPE_ARGS(sb), rc);
 663                         goto out;
 664                 }
 665                 switch (flags[i]) {
 666                 case FSCONTEXT_MNT:
 667                         fscontext_sid = sid;
 668
 669                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 670                                         fscontext_sid))
 671                                 goto out_double_mount;
 672
 673                         sbsec->flags |= FSCONTEXT_MNT;
 674                         break;
 675                 case CONTEXT_MNT:
 676                         context_sid = sid;
 677
 678                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 679                                         context_sid))
 680                                 goto out_double_mount;
 681
 682                         sbsec->flags |= CONTEXT_MNT;
 683                         break;
 684                 case ROOTCONTEXT_MNT:
 685                         rootcontext_sid = sid;
 686
 687                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 688                                         rootcontext_sid))
 689                                 goto out_double_mount;
 690
 691                         sbsec->flags |= ROOTCONTEXT_MNT;
 692
 693                         break;
 694                 case DEFCONTEXT_MNT:
 695                         defcontext_sid = sid;
 696
 697                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 698                                         defcontext_sid))
 699                                 goto out_double_mount;
 700
 701                         sbsec->flags |= DEFCONTEXT_MNT;
 702
 703                         break;
 704                 default:
 705                         rc = -EINVAL;
 706                         goto out;
 707                 }
 708         }
 709
 710         if (sbsec->flags & SE_SBINITIALIZED) {
 711                 /* previously mounted with options, but not on this attempt? */
 712                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
 713                         goto out_double_mount;
 714                 rc = 0;
 715                 goto out;
 716         }
 717
 718         if (strcmp(sb->s_type->name, "proc") == 0)
 719                 sbsec->flags |= SE_SBPROC;
 720
 721         if (!sbsec->behavior) {
 722                 /*
 723                  * Determine the labeling behavior to use for this
 724                  * filesystem type.
 725                  */
 726                 rc = security_fs_use(sb);
 727                 if (rc) {
 728                         printk(KERN_WARNING
 729                                 "%s: security_fs_use(%s) returned %d\n",
 730                                         __func__, sb->s_type->name, rc);
 731                         goto out;
 732                 }
 733         }
 734         /* sets the context of the superblock for the fs being mounted. */
 735         if (fscontext_sid) {
 736                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 737                 if (rc)
 738                         goto out;
 739
 740                 sbsec->sid = fscontext_sid;
 741         }
 742
 743         /*
 744          * Switch to using mount point labeling behavior.
 745          * sets the label used on all file below the mountpoint, and will set
 746          * the superblock context if not already set.
 747          */
 748         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
 749                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 750                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 751         }
 752
 753         if (context_sid) {
 754                 if (!fscontext_sid) {
 755                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 756                                                           cred);
 757                         if (rc)
 758                                 goto out;
 759                         sbsec->sid = context_sid;
 760                 } else {
 761                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 762                                                              cred);
 763                         if (rc)
 764                                 goto out;
 765                 }
 766                 if (!rootcontext_sid)
 767                         rootcontext_sid = context_sid;
 768
 769                 sbsec->mntpoint_sid = context_sid;
 770                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 771         }
 772
 773         if (rootcontext_sid) {
 774                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 775                                                      cred);
 776                 if (rc)
 777                         goto out;
 778
 779                 root_isec->sid = rootcontext_sid;
 780                 root_isec->initialized = 1;
 781         }
 782
 783         if (defcontext_sid) {
 784                 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
 785                         sbsec->behavior != SECURITY_FS_USE_NATIVE) {
 786                         rc = -EINVAL;
 787                         printk(KERN_WARNING "SELinux: defcontext option is "
 788                                "invalid for this filesystem type\n");
 789                         goto out;
 790                 }
 791
 792                 if (defcontext_sid != sbsec->def_sid) {
 793                         rc = may_context_mount_inode_relabel(defcontext_sid,
 794                                                              sbsec, cred);
 795                         if (rc)
 796                                 goto out;
 797                 }
 798
 799                 sbsec->def_sid = defcontext_sid;
 800         }
 801
 802         rc = sb_finish_set_opts(sb);
 803 out:
 804         mutex_unlock(&sbsec->lock);
 805         return rc;
 806 out_double_mount:
 807         rc = -EINVAL;
 808         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 809                "security settings for (dev %s, type "SB_TYPE_FMT")\n", sb->s_id,
 810                SB_TYPE_ARGS(sb));
 811         goto out;
 812 }
 813
 814 static int selinux_cmp_sb_context(const struct super_block *oldsb,
 815                                     const struct super_block *newsb)
 816 {
 817         struct superblock_security_struct *old = oldsb->s_security;
 818         struct superblock_security_struct *new = newsb->s_security;
 819         char oldflags = old->flags & SE_MNTMASK;
 820         char newflags = new->flags & SE_MNTMASK;
 821
 822         if (oldflags != newflags)
 823                 goto mismatch;
 824         if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
 825                 goto mismatch;
 826         if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
 827                 goto mismatch;
 828         if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
 829                 goto mismatch;
 830         if (oldflags & ROOTCONTEXT_MNT) {
 831                 struct inode_security_struct *oldroot = oldsb->s_root->d_inode->i_security;
 832                 struct inode_security_struct *newroot = newsb->s_root->d_inode->i_security;
 833                 if (oldroot->sid != newroot->sid)
 834                         goto mismatch;
 835         }
 836         return 0;
 837 mismatch:
 838         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, "
 839                             "different security settings for (dev %s, "
 840                             "type %s)\n", newsb->s_id, newsb->s_type->name);
 841         return -EBUSY;
 842 }
 843
 844 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 845                                         struct super_block *newsb)
 846 {
 847         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 848         struct superblock_security_struct *newsbsec = newsb->s_security;
 849
 850         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 851         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 852         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 853
 854         /*
 855          * if the parent was able to be mounted it clearly had no special lsm
 856          * mount options.  thus we can safely deal with this superblock later
 857          */
 858         if (!ss_initialized)
 859                 return 0;
 860
 861         /* how can we clone if the old one wasn't set up?? */
 862         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 863
 864         /* if fs is reusing a sb, make sure that the contexts match */
 865         if (newsbsec->flags & SE_SBINITIALIZED)
 866                 return selinux_cmp_sb_context(oldsb, newsb);
 867
 868         mutex_lock(&newsbsec->lock);
 869
 870         newsbsec->flags = oldsbsec->flags;
 871
 872         newsbsec->sid = oldsbsec->sid;
 873         newsbsec->def_sid = oldsbsec->def_sid;
 874         newsbsec->behavior = oldsbsec->behavior;
 875
 876         if (set_context) {
 877                 u32 sid = oldsbsec->mntpoint_sid;
 878
 879                 if (!set_fscontext)
 880                         newsbsec->sid = sid;
 881                 if (!set_rootcontext) {
 882                         struct inode *newinode = newsb->s_root->d_inode;
 883                         struct inode_security_struct *newisec = newinode->i_security;
 884                         newisec->sid = sid;
 885                 }
 886                 newsbsec->mntpoint_sid = sid;
 887         }
 888         if (set_rootcontext) {
 889                 const struct inode *oldinode = oldsb->s_root->d_inode;
 890                 const struct inode_security_struct *oldisec = oldinode->i_security;
 891                 struct inode *newinode = newsb->s_root->d_inode;
 892                 struct inode_security_struct *newisec = newinode->i_security;
 893
 894                 newisec->sid = oldisec->sid;
 895         }
 896
 897         sb_finish_set_opts(newsb);
 898         mutex_unlock(&newsbsec->lock);
 899         return 0;
 900 }
 901
 902 static int selinux_parse_opts_str(char *options,
 903                                   struct security_mnt_opts *opts)
 904 {
 905         char *p;
 906         char *context = NULL, *defcontext = NULL;
 907         char *fscontext = NULL, *rootcontext = NULL;
 908         int rc, num_mnt_opts = 0;
 909
 910         opts->num_mnt_opts = 0;
 911
 912         /* Standard string-based options. */
 913         while ((p = strsep(&options, "|")) != NULL) {
 914                 int token;
 915                 substring_t args[MAX_OPT_ARGS];
 916
 917                 if (!*p)
 918                         continue;
 919
 920                 token = match_token(p, tokens, args);
 921
 922                 switch (token) {
 923                 case Opt_context:
 924                         if (context || defcontext) {
 925                                 rc = -EINVAL;
 926                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 927                                 goto out_err;
 928                         }
 929                         context = match_strdup(&args[0]);
 930                         if (!context) {
 931                                 rc = -ENOMEM;
 932                                 goto out_err;
 933                         }
 934                         break;
 935
 936                 case Opt_fscontext:
 937                         if (fscontext) {
 938                                 rc = -EINVAL;
 939                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 940                                 goto out_err;
 941                         }
 942                         fscontext = match_strdup(&args[0]);
 943                         if (!fscontext) {
 944                                 rc = -ENOMEM;
 945                                 goto out_err;
 946                         }
 947                         break;
 948
 949                 case Opt_rootcontext:
 950                         if (rootcontext) {
 951                                 rc = -EINVAL;
 952                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 953                                 goto out_err;
 954                         }
 955                         rootcontext = match_strdup(&args[0]);
 956                         if (!rootcontext) {
 957                                 rc = -ENOMEM;
 958                                 goto out_err;
 959                         }
 960                         break;
 961
 962                 case Opt_defcontext:
 963                         if (context || defcontext) {
 964                                 rc = -EINVAL;
 965                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
 966                                 goto out_err;
 967                         }
 968                         defcontext = match_strdup(&args[0]);
 969                         if (!defcontext) {
 970                                 rc = -ENOMEM;
 971                                 goto out_err;
 972                         }
 973                         break;
 974                 case Opt_labelsupport:
 975                         break;
 976                 default:
 977                         rc = -EINVAL;
 978                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
 979                         goto out_err;
 980
 981                 }
 982         }
 983
 984         rc = -ENOMEM;
 985         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_ATOMIC);
 986         if (!opts->mnt_opts)
 987                 goto out_err;
 988
 989         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int), GFP_ATOMIC);
 990         if (!opts->mnt_opts_flags) {
 991                 kfree(opts->mnt_opts);
 992                 goto out_err;
 993         }
 994
 995         if (fscontext) {
 996                 opts->mnt_opts[num_mnt_opts] = fscontext;
 997                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
 998         }
 999         if (context) {
1000                 opts->mnt_opts[num_mnt_opts] = context;
1001                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1002         }
1003         if (rootcontext) {
1004                 opts->mnt_opts[num_mnt_opts] = rootcontext;
1005                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1006         }
1007         if (defcontext) {
1008                 opts->mnt_opts[num_mnt_opts] = defcontext;
1009                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1010         }
1011
1012         opts->num_mnt_opts = num_mnt_opts;
1013         return 0;
1014
1015 out_err:
1016         kfree(context);
1017         kfree(defcontext);
1018         kfree(fscontext);
1019         kfree(rootcontext);
1020         return rc;
1021 }
1022 /*
1023  * string mount options parsing and call set the sbsec
1024  */
1025 static int superblock_doinit(struct super_block *sb, void *data)
1026 {
1027         int rc = 0;
1028         char *options = data;
1029         struct security_mnt_opts opts;
1030
1031         security_init_mnt_opts(&opts);
1032
1033         if (!data)
1034                 goto out;
1035
1036         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
1037
1038         rc = selinux_parse_opts_str(options, &opts);
1039         if (rc)
1040                 goto out_err;
1041
1042 out:
1043         rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1044
1045 out_err:
1046         security_free_mnt_opts(&opts);
1047         return rc;
1048 }
1049
1050 static void selinux_write_opts(struct seq_file *m,
1051                                struct security_mnt_opts *opts)
1052 {
1053         int i;
1054         char *prefix;
1055
1056         for (i = 0; i < opts->num_mnt_opts; i++) {
1057                 char *has_comma;
1058
1059                 if (opts->mnt_opts[i])
1060                         has_comma = strchr(opts->mnt_opts[i], ',');
1061                 else
1062                         has_comma = NULL;
1063
1064                 switch (opts->mnt_opts_flags[i]) {
1065                 case CONTEXT_MNT:
1066                         prefix = CONTEXT_STR;
1067                         break;
1068                 case FSCONTEXT_MNT:
1069                         prefix = FSCONTEXT_STR;
1070                         break;
1071                 case ROOTCONTEXT_MNT:
1072                         prefix = ROOTCONTEXT_STR;
1073                         break;
1074                 case DEFCONTEXT_MNT:
1075                         prefix = DEFCONTEXT_STR;
1076                         break;
1077                 case SBLABEL_MNT:
1078                         seq_putc(m, ',');
1079                         seq_puts(m, LABELSUPP_STR);
1080                         continue;
1081                 default:
1082                         BUG();
1083                         return;
1084                 };
1085                 /* we need a comma before each option */
1086                 seq_putc(m, ',');
1087                 seq_puts(m, prefix);
1088                 if (has_comma)
1089                         seq_putc(m, '\"');
1090                 seq_puts(m, opts->mnt_opts[i]);
1091                 if (has_comma)
1092                         seq_putc(m, '\"');
1093         }
1094 }
1095
1096 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1097 {
1098         struct security_mnt_opts opts;
1099         int rc;
1100
1101         rc = selinux_get_mnt_opts(sb, &opts);
1102         if (rc) {
1103                 /* before policy load we may get EINVAL, don't show anything */
1104                 if (rc == -EINVAL)
1105                         rc = 0;
1106                 return rc;
1107         }
1108
1109         selinux_write_opts(m, &opts);
1110
1111         security_free_mnt_opts(&opts);
1112
1113         return rc;
1114 }
1115
1116 static inline u16 inode_mode_to_security_class(umode_t mode)
1117 {
1118         switch (mode & S_IFMT) {
1119         case S_IFSOCK:
1120                 return SECCLASS_SOCK_FILE;
1121         case S_IFLNK:
1122                 return SECCLASS_LNK_FILE;
1123         case S_IFREG:
1124                 return SECCLASS_FILE;
1125         case S_IFBLK:
1126                 return SECCLASS_BLK_FILE;
1127         case S_IFDIR:
1128                 return SECCLASS_DIR;
1129         case S_IFCHR:
1130                 return SECCLASS_CHR_FILE;
1131         case S_IFIFO:
1132                 return SECCLASS_FIFO_FILE;
1133
1134         }
1135
1136         return SECCLASS_FILE;
1137 }
1138
1139 static inline int default_protocol_stream(int protocol)
1140 {
1141         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1142 }
1143
1144 static inline int default_protocol_dgram(int protocol)
1145 {
1146         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1147 }
1148
1149 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1150 {
1151         switch (family) {
1152         case PF_UNIX:
1153                 switch (type) {
1154                 case SOCK_STREAM:
1155                 case SOCK_SEQPACKET:
1156                         return SECCLASS_UNIX_STREAM_SOCKET;
1157                 case SOCK_DGRAM:
1158                         return SECCLASS_UNIX_DGRAM_SOCKET;
1159                 }
1160                 break;
1161         case PF_INET:
1162         case PF_INET6:
1163                 switch (type) {
1164                 case SOCK_STREAM:
1165                         if (default_protocol_stream(protocol))
1166                                 return SECCLASS_TCP_SOCKET;
1167                         else
1168                                 return SECCLASS_RAWIP_SOCKET;
1169                 case SOCK_DGRAM:
1170                         if (default_protocol_dgram(protocol))
1171                                 return SECCLASS_UDP_SOCKET;
1172                         else
1173                                 return SECCLASS_RAWIP_SOCKET;
1174                 case SOCK_DCCP:
1175                         return SECCLASS_DCCP_SOCKET;
1176                 default:
1177                         return SECCLASS_RAWIP_SOCKET;
1178                 }
1179                 break;
1180         case PF_NETLINK:
1181                 switch (protocol) {
1182                 case NETLINK_ROUTE:
1183                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1184                 case NETLINK_FIREWALL:
1185                         return SECCLASS_NETLINK_FIREWALL_SOCKET;
1186                 case NETLINK_SOCK_DIAG:
1187                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1188                 case NETLINK_NFLOG:
1189                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1190                 case NETLINK_XFRM:
1191                         return SECCLASS_NETLINK_XFRM_SOCKET;
1192                 case NETLINK_SELINUX:
1193                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1194                 case NETLINK_AUDIT:
1195                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1196                 case NETLINK_IP6_FW:
1197                         return SECCLASS_NETLINK_IP6FW_SOCKET;
1198                 case NETLINK_DNRTMSG:
1199                         return SECCLASS_NETLINK_DNRT_SOCKET;
1200                 case NETLINK_KOBJECT_UEVENT:
1201                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1202                 default:
1203                         return SECCLASS_NETLINK_SOCKET;
1204                 }
1205         case PF_PACKET:
1206                 return SECCLASS_PACKET_SOCKET;
1207         case PF_KEY:
1208                 return SECCLASS_KEY_SOCKET;
1209         case PF_APPLETALK:
1210                 return SECCLASS_APPLETALK_SOCKET;
1211         }
1212
1213         return SECCLASS_SOCKET;
1214 }
1215
1216 #ifdef CONFIG_PROC_FS
1217 static int selinux_proc_get_sid(struct dentry *dentry,
1218                                 u16 tclass,
1219                                 u32 *sid)
1220 {
1221         int rc;
1222         char *buffer, *path;
1223
1224         buffer = (char *)__get_free_page(GFP_KERNEL);
1225         if (!buffer)
1226                 return -ENOMEM;
1227
1228         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1229         if (IS_ERR(path))
1230                 rc = PTR_ERR(path);
1231         else {
1232                 /* each process gets a /proc/PID/ entry. Strip off the
1233                  * PID part to get a valid selinux labeling.
1234                  * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1235                 while (path[1] >= '0' && path[1] <= '9') {
1236                         path[1] = '/';
1237                         path++;
1238                 }
1239                 rc = security_genfs_sid("proc", path, tclass, sid);
1240         }
1241         free_page((unsigned long)buffer);
1242         return rc;
1243 }
1244 #else
1245 static int selinux_proc_get_sid(struct dentry *dentry,
1246                                 u16 tclass,
1247                                 u32 *sid)
1248 {
1249         return -EINVAL;
1250 }
1251 #endif
1252
1253 /* The inode's security attributes must be initialized before first use. */
1254 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1255 {
1256         struct superblock_security_struct *sbsec = NULL;
1257         struct inode_security_struct *isec = inode->i_security;
1258         u32 sid;
1259         struct dentry *dentry;
1260 #define INITCONTEXTLEN 255
1261         char *context = NULL;
1262         unsigned len = 0;
1263         int rc = 0;
1264
1265         if (isec->initialized)
1266                 goto out;
1267
1268         mutex_lock(&isec->lock);
1269         if (isec->initialized)
1270                 goto out_unlock;
1271
1272         sbsec = inode->i_sb->s_security;
1273         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1274                 /* Defer initialization until selinux_complete_init,
1275                    after the initial policy is loaded and the security
1276                    server is ready to handle calls. */
1277                 spin_lock(&sbsec->isec_lock);
1278                 if (list_empty(&isec->list))
1279                         list_add(&isec->list, &sbsec->isec_head);
1280                 spin_unlock(&sbsec->isec_lock);
1281                 goto out_unlock;
1282         }
1283
1284         switch (sbsec->behavior) {
1285         case SECURITY_FS_USE_NATIVE:
1286                 break;
1287         case SECURITY_FS_USE_XATTR:
1288                 if (!inode->i_op->getxattr) {
1289                         isec->sid = sbsec->def_sid;
1290                         break;
1291                 }
1292
1293                 /* Need a dentry, since the xattr API requires one.
1294                    Life would be simpler if we could just pass the inode. */
1295                 if (opt_dentry) {
1296                         /* Called from d_instantiate or d_splice_alias. */
1297                         dentry = dget(opt_dentry);
1298                 } else {
1299                         /* Called from selinux_complete_init, try to find a dentry. */
1300                         dentry = d_find_alias(inode);
1301                 }
1302                 if (!dentry) {
1303                         /*
1304                          * this is can be hit on boot when a file is accessed
1305                          * before the policy is loaded.  When we load policy we
1306                          * may find inodes that have no dentry on the
1307                          * sbsec->isec_head list.  No reason to complain as these
1308                          * will get fixed up the next time we go through
1309                          * inode_doinit with a dentry, before these inodes could
1310                          * be used again by userspace.
1311                          */
1312                         goto out_unlock;
1313                 }
1314
1315                 len = INITCONTEXTLEN;
1316                 context = kmalloc(len+1, GFP_NOFS);
1317                 if (!context) {
1318                         rc = -ENOMEM;
1319                         dput(dentry);
1320                         goto out_unlock;
1321                 }
1322                 context[len] = '\0';
1323                 rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1324                                            context, len);
1325                 if (rc == -ERANGE) {
1326                         kfree(context);
1327
1328                         /* Need a larger buffer.  Query for the right size. */
1329                         rc = inode->i_op->getxattr(dentry, XATTR_NAME_SELINUX,
1330                                                    NULL, 0);
1331                         if (rc < 0) {
1332                                 dput(dentry);
1333                                 goto out_unlock;
1334                         }
1335                         len = rc;
1336                         context = kmalloc(len+1, GFP_NOFS);
1337                         if (!context) {
1338                                 rc = -ENOMEM;
1339                                 dput(dentry);
1340                                 goto out_unlock;
1341                         }
1342                         context[len] = '\0';
1343                         rc = inode->i_op->getxattr(dentry,
1344                                                    XATTR_NAME_SELINUX,
1345                                                    context, len);
1346                 }
1347                 dput(dentry);
1348                 if (rc < 0) {
1349                         if (rc != -ENODATA) {
1350                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1351                                        "%d for dev=%s ino=%ld\n", __func__,
1352                                        -rc, inode->i_sb->s_id, inode->i_ino);
1353                                 kfree(context);
1354                                 goto out_unlock;
1355                         }
1356                         /* Map ENODATA to the default file SID */
1357                         sid = sbsec->def_sid;
1358                         rc = 0;
1359                 } else {
1360                         rc = security_context_to_sid_default(context, rc, &sid,
1361                                                              sbsec->def_sid,
1362                                                              GFP_NOFS);
1363                         if (rc) {
1364                                 char *dev = inode->i_sb->s_id;
1365                                 unsigned long ino = inode->i_ino;
1366
1367                                 if (rc == -EINVAL) {
1368                                         if (printk_ratelimit())
1369                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1370                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1371                                                         "filesystem in question.\n", ino, dev, context);
1372                                 } else {
1373                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1374                                                "returned %d for dev=%s ino=%ld\n",
1375                                                __func__, context, -rc, dev, ino);
1376                                 }
1377                                 kfree(context);
1378                                 /* Leave with the unlabeled SID */
1379                                 rc = 0;
1380                                 break;
1381                         }
1382                 }
1383                 kfree(context);
1384                 isec->sid = sid;
1385                 break;
1386         case SECURITY_FS_USE_TASK:
1387                 isec->sid = isec->task_sid;
1388                 break;
1389         case SECURITY_FS_USE_TRANS:
1390                 /* Default to the fs SID. */
1391                 isec->sid = sbsec->sid;
1392
1393                 /* Try to obtain a transition SID. */
1394                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1395                 rc = security_transition_sid(isec->task_sid, sbsec->sid,
1396                                              isec->sclass, NULL, &sid);
1397                 if (rc)
1398                         goto out_unlock;
1399                 isec->sid = sid;
1400                 break;
1401         case SECURITY_FS_USE_MNTPOINT:
1402                 isec->sid = sbsec->mntpoint_sid;
1403                 break;
1404         default:
1405                 /* Default to the fs superblock SID. */
1406                 isec->sid = sbsec->sid;
1407
1408                 if ((sbsec->flags & SE_SBPROC) && !S_ISLNK(inode->i_mode)) {
1409                         if (opt_dentry) {
1410                                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1411                                 rc = selinux_proc_get_sid(opt_dentry,
1412                                                           isec->sclass,
1413                                                           &sid);
1414                                 if (rc)
1415                                         goto out_unlock;
1416                                 isec->sid = sid;
1417                         }
1418                 }
1419                 break;
1420         }
1421
1422         isec->initialized = 1;
1423
1424 out_unlock:
1425         mutex_unlock(&isec->lock);
1426 out:
1427         if (isec->sclass == SECCLASS_FILE)
1428                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1429         return rc;
1430 }
1431
1432 /* Convert a Linux signal to an access vector. */
1433 static inline u32 signal_to_av(int sig)
1434 {
1435         u32 perm = 0;
1436
1437         switch (sig) {
1438         case SIGCHLD:
1439                 /* Commonly granted from child to parent. */
1440                 perm = PROCESS__SIGCHLD;
1441                 break;
1442         case SIGKILL:
1443                 /* Cannot be caught or ignored */
1444                 perm = PROCESS__SIGKILL;
1445                 break;
1446         case SIGSTOP:
1447                 /* Cannot be caught or ignored */
1448                 perm = PROCESS__SIGSTOP;
1449                 break;
1450         default:
1451                 /* All other signals. */
1452                 perm = PROCESS__SIGNAL;
1453                 break;
1454         }
1455
1456         return perm;
1457 }
1458
1459 /*
1460  * Check permission between a pair of credentials
1461  * fork check, ptrace check, etc.
1462  */
1463 static int cred_has_perm(const struct cred *actor,
1464                          const struct cred *target,
1465                          u32 perms)
1466 {
1467         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1468
1469         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1470 }
1471
1472 /*
1473  * Check permission between a pair of tasks, e.g. signal checks,
1474  * fork check, ptrace check, etc.
1475  * tsk1 is the actor and tsk2 is the target
1476  * - this uses the default subjective creds of tsk1
1477  */
1478 static int task_has_perm(const struct task_struct *tsk1,
1479                          const struct task_struct *tsk2,
1480                          u32 perms)
1481 {
1482         const struct task_security_struct *__tsec1, *__tsec2;
1483         u32 sid1, sid2;
1484
1485         rcu_read_lock();
1486         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1487         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1488         rcu_read_unlock();
1489         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1490 }
1491
1492 /*
1493  * Check permission between current and another task, e.g. signal checks,
1494  * fork check, ptrace check, etc.
1495  * current is the actor and tsk2 is the target
1496  * - this uses current's subjective creds
1497  */
1498 static int current_has_perm(const struct task_struct *tsk,
1499                             u32 perms)
1500 {
1501         u32 sid, tsid;
1502
1503         sid = current_sid();
1504         tsid = task_sid(tsk);
1505         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1506 }
1507
1508 #if CAP_LAST_CAP > 63
1509 #error Fix SELinux to handle capabilities > 63.
1510 #endif
1511
1512 /* Check whether a task is allowed to use a capability. */
1513 static int cred_has_capability(const struct cred *cred,
1514                                int cap, int audit)
1515 {
1516         struct common_audit_data ad;
1517         struct av_decision avd;
1518         u16 sclass;
1519         u32 sid = cred_sid(cred);
1520         u32 av = CAP_TO_MASK(cap);
1521         int rc;
1522
1523         ad.type = LSM_AUDIT_DATA_CAP;
1524         ad.u.cap = cap;
1525
1526         switch (CAP_TO_INDEX(cap)) {
1527         case 0:
1528                 sclass = SECCLASS_CAPABILITY;
1529                 break;
1530         case 1:
1531                 sclass = SECCLASS_CAPABILITY2;
1532                 break;
1533         default:
1534                 printk(KERN_ERR
1535                        "SELinux:  out of range capability %d\n", cap);
1536                 BUG();
1537                 return -EINVAL;
1538         }
1539
1540         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1541         if (audit == SECURITY_CAP_AUDIT) {
1542                 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1543                 if (rc2)
1544                         return rc2;
1545         }
1546         return rc;
1547 }
1548
1549 /* Check whether a task is allowed to use a system operation. */
1550 static int task_has_system(struct task_struct *tsk,
1551                            u32 perms)
1552 {
1553         u32 sid = task_sid(tsk);
1554
1555         return avc_has_perm(sid, SECINITSID_KERNEL,
1556                             SECCLASS_SYSTEM, perms, NULL);
1557 }
1558
1559 /* Check whether a task has a particular permission to an inode.
1560    The 'adp' parameter is optional and allows other audit
1561    data to be passed (e.g. the dentry). */
1562 static int inode_has_perm(const struct cred *cred,
1563                           struct inode *inode,
1564                           u32 perms,
1565                           struct common_audit_data *adp,
1566                           unsigned flags)
1567 {
1568         struct inode_security_struct *isec;
1569         u32 sid;
1570
1571         validate_creds(cred);
1572
1573         if (unlikely(IS_PRIVATE(inode)))
1574                 return 0;
1575
1576         sid = cred_sid(cred);
1577         isec = inode->i_security;
1578
1579         return avc_has_perm_flags(sid, isec->sid, isec->sclass, perms, adp, flags);
1580 }
1581
1582 /* Same as inode_has_perm, but pass explicit audit data containing
1583    the dentry to help the auditing code to more easily generate the
1584    pathname if needed. */
1585 static inline int dentry_has_perm(const struct cred *cred,
1586                                   struct dentry *dentry,
1587                                   u32 av)
1588 {
1589         struct inode *inode = dentry->d_inode;
1590         struct common_audit_data ad;
1591
1592         ad.type = LSM_AUDIT_DATA_DENTRY;
1593         ad.u.dentry = dentry;
1594         return inode_has_perm(cred, inode, av, &ad, 0);
1595 }
1596
1597 /* Same as inode_has_perm, but pass explicit audit data containing
1598    the path to help the auditing code to more easily generate the
1599    pathname if needed. */
1600 static inline int path_has_perm(const struct cred *cred,
1601                                 struct path *path,
1602                                 u32 av)
1603 {
1604         struct inode *inode = path->dentry->d_inode;
1605         struct common_audit_data ad;
1606
1607         ad.type = LSM_AUDIT_DATA_PATH;
1608         ad.u.path = *path;
1609         return inode_has_perm(cred, inode, av, &ad, 0);
1610 }
1611
1612 /* Same as path_has_perm, but uses the inode from the file struct. */
1613 static inline int file_path_has_perm(const struct cred *cred,
1614                                      struct file *file,
1615                                      u32 av)
1616 {
1617         struct common_audit_data ad;
1618
1619         ad.type = LSM_AUDIT_DATA_PATH;
1620         ad.u.path = file->f_path;
1621         return inode_has_perm(cred, file_inode(file), av, &ad, 0);
1622 }
1623
1624 /* Check whether a task can use an open file descriptor to
1625    access an inode in a given way.  Check access to the
1626    descriptor itself, and then use dentry_has_perm to
1627    check a particular permission to the file.
1628    Access to the descriptor is implicitly granted if it
1629    has the same SID as the process.  If av is zero, then
1630    access to the file is not checked, e.g. for cases
1631    where only the descriptor is affected like seek. */
1632 static int file_has_perm(const struct cred *cred,
1633                          struct file *file,
1634                          u32 av)
1635 {
1636         struct file_security_struct *fsec = file->f_security;
1637         struct inode *inode = file_inode(file);
1638         struct common_audit_data ad;
1639         u32 sid = cred_sid(cred);
1640         int rc;
1641
1642         ad.type = LSM_AUDIT_DATA_PATH;
1643         ad.u.path = file->f_path;
1644
1645         if (sid != fsec->sid) {
1646                 rc = avc_has_perm(sid, fsec->sid,
1647                                   SECCLASS_FD,
1648                                   FD__USE,
1649                                   &ad);
1650                 if (rc)
1651                         goto out;
1652         }
1653
1654         /* av is zero if only checking access to the descriptor. */
1655         rc = 0;
1656         if (av)
1657                 rc = inode_has_perm(cred, inode, av, &ad, 0);
1658
1659 out:
1660         return rc;
1661 }
1662
1663 /* Check whether a task can create a file. */
1664 static int may_create(struct inode *dir,
1665                       struct dentry *dentry,
1666                       u16 tclass)
1667 {
1668         const struct task_security_struct *tsec = current_security();
1669         struct inode_security_struct *dsec;
1670         struct superblock_security_struct *sbsec;
1671         u32 sid, newsid;
1672         struct common_audit_data ad;
1673         int rc;
1674
1675         dsec = dir->i_security;
1676         sbsec = dir->i_sb->s_security;
1677
1678         sid = tsec->sid;
1679         newsid = tsec->create_sid;
1680
1681         ad.type = LSM_AUDIT_DATA_DENTRY;
1682         ad.u.dentry = dentry;
1683
1684         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1685                           DIR__ADD_NAME | DIR__SEARCH,
1686                           &ad);
1687         if (rc)
1688                 return rc;
1689
1690         if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
1691                 rc = security_transition_sid(sid, dsec->sid, tclass,
1692                                              &dentry->d_name, &newsid);
1693                 if (rc)
1694                         return rc;
1695         }
1696
1697         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1698         if (rc)
1699                 return rc;
1700
1701         return avc_has_perm(newsid, sbsec->sid,
1702                             SECCLASS_FILESYSTEM,
1703                             FILESYSTEM__ASSOCIATE, &ad);
1704 }
1705
1706 /* Check whether a task can create a key. */
1707 static int may_create_key(u32 ksid,
1708                           struct task_struct *ctx)
1709 {
1710         u32 sid = task_sid(ctx);
1711
1712         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1713 }
1714
1715 #define MAY_LINK        0
1716 #define MAY_UNLINK      1
1717 #define MAY_RMDIR       2
1718
1719 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1720 static int may_link(struct inode *dir,
1721                     struct dentry *dentry,
1722                     int kind)
1723
1724 {
1725         struct inode_security_struct *dsec, *isec;
1726         struct common_audit_data ad;
1727         u32 sid = current_sid();
1728         u32 av;
1729         int rc;
1730
1731         dsec = dir->i_security;
1732         isec = dentry->d_inode->i_security;
1733
1734         ad.type = LSM_AUDIT_DATA_DENTRY;
1735         ad.u.dentry = dentry;
1736
1737         av = DIR__SEARCH;
1738         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1739         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1740         if (rc)
1741                 return rc;
1742
1743         switch (kind) {
1744         case MAY_LINK:
1745                 av = FILE__LINK;
1746                 break;
1747         case MAY_UNLINK:
1748                 av = FILE__UNLINK;
1749                 break;
1750         case MAY_RMDIR:
1751                 av = DIR__RMDIR;
1752                 break;
1753         default:
1754                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1755                         __func__, kind);
1756                 return 0;
1757         }
1758
1759         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1760         return rc;
1761 }
1762
1763 static inline int may_rename(struct inode *old_dir,
1764                              struct dentry *old_dentry,
1765                              struct inode *new_dir,
1766                              struct dentry *new_dentry)
1767 {
1768         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1769         struct common_audit_data ad;
1770         u32 sid = current_sid();
1771         u32 av;
1772         int old_is_dir, new_is_dir;
1773         int rc;
1774
1775         old_dsec = old_dir->i_security;
1776         old_isec = old_dentry->d_inode->i_security;
1777         old_is_dir = S_ISDIR(old_dentry->d_inode->i_mode);
1778         new_dsec = new_dir->i_security;
1779
1780         ad.type = LSM_AUDIT_DATA_DENTRY;
1781
1782         ad.u.dentry = old_dentry;
1783         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1784                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1785         if (rc)
1786                 return rc;
1787         rc = avc_has_perm(sid, old_isec->sid,
1788                           old_isec->sclass, FILE__RENAME, &ad);
1789         if (rc)
1790                 return rc;
1791         if (old_is_dir && new_dir != old_dir) {
1792                 rc = avc_has_perm(sid, old_isec->sid,
1793                                   old_isec->sclass, DIR__REPARENT, &ad);
1794                 if (rc)
1795                         return rc;
1796         }
1797
1798         ad.u.dentry = new_dentry;
1799         av = DIR__ADD_NAME | DIR__SEARCH;
1800         if (new_dentry->d_inode)
1801                 av |= DIR__REMOVE_NAME;
1802         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1803         if (rc)
1804                 return rc;
1805         if (new_dentry->d_inode) {
1806                 new_isec = new_dentry->d_inode->i_security;
1807                 new_is_dir = S_ISDIR(new_dentry->d_inode->i_mode);
1808                 rc = avc_has_perm(sid, new_isec->sid,
1809                                   new_isec->sclass,
1810                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1811                 if (rc)
1812                         return rc;
1813         }
1814
1815         return 0;
1816 }
1817
1818 /* Check whether a task can perform a filesystem operation. */
1819 static int superblock_has_perm(const struct cred *cred,
1820                                struct super_block *sb,
1821                                u32 perms,
1822                                struct common_audit_data *ad)
1823 {
1824         struct superblock_security_struct *sbsec;
1825         u32 sid = cred_sid(cred);
1826
1827         sbsec = sb->s_security;
1828         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
1829 }
1830
1831 /* Convert a Linux mode and permission mask to an access vector. */
1832 static inline u32 file_mask_to_av(int mode, int mask)
1833 {
1834         u32 av = 0;
1835
1836         if (!S_ISDIR(mode)) {
1837                 if (mask & MAY_EXEC)
1838                         av |= FILE__EXECUTE;
1839                 if (mask & MAY_READ)
1840                         av |= FILE__READ;
1841
1842                 if (mask & MAY_APPEND)
1843                         av |= FILE__APPEND;
1844                 else if (mask & MAY_WRITE)
1845                         av |= FILE__WRITE;
1846
1847         } else {
1848                 if (mask & MAY_EXEC)
1849                         av |= DIR__SEARCH;
1850                 if (mask & MAY_WRITE)
1851                         av |= DIR__WRITE;
1852                 if (mask & MAY_READ)
1853                         av |= DIR__READ;
1854         }
1855
1856         return av;
1857 }
1858
1859 /* Convert a Linux file to an access vector. */
1860 static inline u32 file_to_av(struct file *file)
1861 {
1862         u32 av = 0;
1863
1864         if (file->f_mode & FMODE_READ)
1865                 av |= FILE__READ;
1866         if (file->f_mode & FMODE_WRITE) {
1867                 if (file->f_flags & O_APPEND)
1868                         av |= FILE__APPEND;
1869                 else
1870                         av |= FILE__WRITE;
1871         }
1872         if (!av) {
1873                 /*
1874                  * Special file opened with flags 3 for ioctl-only use.
1875                  */
1876                 av = FILE__IOCTL;
1877         }
1878
1879         return av;
1880 }
1881
1882 /*
1883  * Convert a file to an access vector and include the correct open
1884  * open permission.
1885  */
1886 static inline u32 open_file_to_av(struct file *file)
1887 {
1888         u32 av = file_to_av(file);
1889
1890         if (selinux_policycap_openperm)
1891                 av |= FILE__OPEN;
1892
1893         return av;
1894 }
1895
1896 /* Hook functions begin here. */
1897
1898 static int selinux_ptrace_access_check(struct task_struct *child,
1899                                      unsigned int mode)
1900 {
1901         int rc;
1902
1903         rc = cap_ptrace_access_check(child, mode);
1904         if (rc)
1905                 return rc;
1906
1907         if (mode & PTRACE_MODE_READ) {
1908                 u32 sid = current_sid();
1909                 u32 csid = task_sid(child);
1910                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
1911         }
1912
1913         return current_has_perm(child, PROCESS__PTRACE);
1914 }
1915
1916 static int selinux_ptrace_traceme(struct task_struct *parent)
1917 {
1918         int rc;
1919
1920         rc = cap_ptrace_traceme(parent);
1921         if (rc)
1922                 return rc;
1923
1924         return task_has_perm(parent, current, PROCESS__PTRACE);
1925 }
1926
1927 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
1928                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
1929 {
1930         int error;
1931
1932         error = current_has_perm(target, PROCESS__GETCAP);
1933         if (error)
1934                 return error;
1935
1936         return cap_capget(target, effective, inheritable, permitted);
1937 }
1938
1939 static int selinux_capset(struct cred *new, const struct cred *old,
1940                           const kernel_cap_t *effective,
1941                           const kernel_cap_t *inheritable,
1942                           const kernel_cap_t *permitted)
1943 {
1944         int error;
1945
1946         error = cap_capset(new, old,
1947                                       effective, inheritable, permitted);
1948         if (error)
1949                 return error;
1950
1951         return cred_has_perm(old, new, PROCESS__SETCAP);
1952 }
1953
1954 /*
1955  * (This comment used to live with the selinux_task_setuid hook,
1956  * which was removed).
1957  *
1958  * Since setuid only affects the current process, and since the SELinux
1959  * controls are not based on the Linux identity attributes, SELinux does not
1960  * need to control this operation.  However, SELinux does control the use of
1961  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
1962  */
1963
1964 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
1965                            int cap, int audit)
1966 {
1967         int rc;
1968
1969         rc = cap_capable(cred, ns, cap, audit);
1970         if (rc)
1971                 return rc;
1972
1973         return cred_has_capability(cred, cap, audit);
1974 }
1975
1976 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
1977 {
1978         const struct cred *cred = current_cred();
1979         int rc = 0;
1980
1981         if (!sb)
1982                 return 0;
1983
1984         switch (cmds) {
1985         case Q_SYNC:
1986         case Q_QUOTAON:
1987         case Q_QUOTAOFF:
1988         case Q_SETINFO:
1989         case Q_SETQUOTA:
1990                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
1991                 break;
1992         case Q_GETFMT:
1993         case Q_GETINFO:
1994         case Q_GETQUOTA:
1995                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
1996                 break;
1997         default:
1998                 rc = 0;  /* let the kernel handle invalid cmds */
1999                 break;
2000         }
2001         return rc;
2002 }
2003
2004 static int selinux_quota_on(struct dentry *dentry)
2005 {
2006         const struct cred *cred = current_cred();
2007
2008         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2009 }
2010
2011 static int selinux_syslog(int type)
2012 {
2013         int rc;
2014
2015         switch (type) {
2016         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2017         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2018                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2019                 break;
2020         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2021         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2022         /* Set level of messages printed to console */
2023         case SYSLOG_ACTION_CONSOLE_LEVEL:
2024                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2025                 break;
2026         case SYSLOG_ACTION_CLOSE:       /* Close log */
2027         case SYSLOG_ACTION_OPEN:        /* Open log */
2028         case SYSLOG_ACTION_READ:        /* Read from log */
2029         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
2030         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
2031         default:
2032                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2033                 break;
2034         }
2035         return rc;
2036 }
2037
2038 /*
2039  * Check that a process has enough memory to allocate a new virtual
2040  * mapping. 0 means there is enough memory for the allocation to
2041  * succeed and -ENOMEM implies there is not.
2042  *
2043  * Do not audit the selinux permission check, as this is applied to all
2044  * processes that allocate mappings.
2045  */
2046 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2047 {
2048         int rc, cap_sys_admin = 0;
2049
2050         rc = selinux_capable(current_cred(), &init_user_ns, CAP_SYS_ADMIN,
2051                              SECURITY_CAP_NOAUDIT);
2052         if (rc == 0)
2053                 cap_sys_admin = 1;
2054
2055         return __vm_enough_memory(mm, pages, cap_sys_admin);
2056 }
2057
2058 /* binprm security operations */
2059
2060 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2061 {
2062         const struct task_security_struct *old_tsec;
2063         struct task_security_struct *new_tsec;
2064         struct inode_security_struct *isec;
2065         struct common_audit_data ad;
2066         struct inode *inode = file_inode(bprm->file);
2067         int rc;
2068
2069         rc = cap_bprm_set_creds(bprm);
2070         if (rc)
2071                 return rc;
2072
2073         /* SELinux context only depends on initial program or script and not
2074          * the script interpreter */
2075         if (bprm->cred_prepared)
2076                 return 0;
2077
2078         old_tsec = current_security();
2079         new_tsec = bprm->cred->security;
2080         isec = inode->i_security;
2081
2082         /* Default to the current task SID. */
2083         new_tsec->sid = old_tsec->sid;
2084         new_tsec->osid = old_tsec->sid;
2085
2086         /* Reset fs, key, and sock SIDs on execve. */
2087         new_tsec->create_sid = 0;
2088         new_tsec->keycreate_sid = 0;
2089         new_tsec->sockcreate_sid = 0;
2090
2091         if (old_tsec->exec_sid) {
2092                 new_tsec->sid = old_tsec->exec_sid;
2093                 /* Reset exec SID on execve. */
2094                 new_tsec->exec_sid = 0;
2095
2096                 /*
2097                  * Minimize confusion: if no_new_privs and a transition is
2098                  * explicitly requested, then fail the exec.
2099                  */
2100                 if (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)
2101                         return -EPERM;
2102         } else {
2103                 /* Check for a default transition on this program. */
2104                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2105                                              SECCLASS_PROCESS, NULL,
2106                                              &new_tsec->sid);
2107                 if (rc)
2108                         return rc;
2109         }
2110
2111         ad.type = LSM_AUDIT_DATA_PATH;
2112         ad.u.path = bprm->file->f_path;
2113
2114         if ((bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) ||
2115             (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS))
2116                 new_tsec->sid = old_tsec->sid;
2117
2118         if (new_tsec->sid == old_tsec->sid) {
2119                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2120                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2121                 if (rc)
2122                         return rc;
2123         } else {
2124                 /* Check permissions for the transition. */
2125                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2126                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2127                 if (rc)
2128                         return rc;
2129
2130                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2131                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2132                 if (rc)
2133                         return rc;
2134
2135                 /* Check for shared state */
2136                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2137                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2138                                           SECCLASS_PROCESS, PROCESS__SHARE,
2139                                           NULL);
2140                         if (rc)
2141                                 return -EPERM;
2142                 }
2143
2144                 /* Make sure that anyone attempting to ptrace over a task that
2145                  * changes its SID has the appropriate permit */
2146                 if (bprm->unsafe &
2147                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2148                         struct task_struct *tracer;
2149                         struct task_security_struct *sec;
2150                         u32 ptsid = 0;
2151
2152                         rcu_read_lock();
2153                         tracer = ptrace_parent(current);
2154                         if (likely(tracer != NULL)) {
2155                                 sec = __task_cred(tracer)->security;
2156                                 ptsid = sec->sid;
2157                         }
2158                         rcu_read_unlock();
2159
2160                         if (ptsid != 0) {
2161                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2162                                                   SECCLASS_PROCESS,
2163                                                   PROCESS__PTRACE, NULL);
2164                                 if (rc)
2165                                         return -EPERM;
2166                         }
2167                 }
2168
2169                 /* Clear any possibly unsafe personality bits on exec: */
2170                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2171         }
2172
2173         return 0;
2174 }
2175
2176 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2177 {
2178         const struct task_security_struct *tsec = current_security();
2179         u32 sid, osid;
2180         int atsecure = 0;
2181
2182         sid = tsec->sid;
2183         osid = tsec->osid;
2184
2185         if (osid != sid) {
2186                 /* Enable secure mode for SIDs transitions unless
2187                    the noatsecure permission is granted between
2188                    the two SIDs, i.e. ahp returns 0. */
2189                 atsecure = avc_has_perm(osid, sid,
2190                                         SECCLASS_PROCESS,
2191                                         PROCESS__NOATSECURE, NULL);
2192         }
2193
2194         return (atsecure || cap_bprm_secureexec(bprm));
2195 }
2196
2197 static int match_file(const void *p, struct file *file, unsigned fd)
2198 {
2199         return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2200 }
2201
2202 /* Derived from fs/exec.c:flush_old_files. */
2203 static inline void flush_unauthorized_files(const struct cred *cred,
2204                                             struct files_struct *files)
2205 {
2206         struct file *file, *devnull = NULL;
2207         struct tty_struct *tty;
2208         int drop_tty = 0;
2209         unsigned n;
2210
2211         tty = get_current_tty();
2212         if (tty) {
2213                 spin_lock(&tty_files_lock);
2214                 if (!list_empty(&tty->tty_files)) {
2215                         struct tty_file_private *file_priv;
2216
2217                         /* Revalidate access to controlling tty.
2218                            Use file_path_has_perm on the tty path directly
2219                            rather than using file_has_perm, as this particular
2220                            open file may belong to another process and we are
2221                            only interested in the inode-based check here. */
2222                         file_priv = list_first_entry(&tty->tty_files,
2223                                                 struct tty_file_private, list);
2224                         file = file_priv->file;
2225                         if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2226                                 drop_tty = 1;
2227                 }
2228                 spin_unlock(&tty_files_lock);
2229                 tty_kref_put(tty);
2230         }
2231         /* Reset controlling tty. */
2232         if (drop_tty)
2233                 no_tty();
2234
2235         /* Revalidate access to inherited open files. */
2236         n = iterate_fd(files, 0, match_file, cred);
2237         if (!n) /* none found? */
2238                 return;
2239
2240         devnull = dentry_open(&selinux_null, O_RDWR, cred);
2241         if (IS_ERR(devnull))
2242                 devnull = NULL;
2243         /* replace all the matching ones with this */
2244         do {
2245                 replace_fd(n - 1, devnull, 0);
2246         } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2247         if (devnull)
2248                 fput(devnull);
2249 }
2250
2251 /*
2252  * Prepare a process for imminent new credential changes due to exec
2253  */
2254 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2255 {
2256         struct task_security_struct *new_tsec;
2257         struct rlimit *rlim, *initrlim;
2258         int rc, i;
2259
2260         new_tsec = bprm->cred->security;
2261         if (new_tsec->sid == new_tsec->osid)
2262                 return;
2263
2264         /* Close files for which the new task SID is not authorized. */
2265         flush_unauthorized_files(bprm->cred, current->files);
2266
2267         /* Always clear parent death signal on SID transitions. */
2268         current->pdeath_signal = 0;
2269
2270         /* Check whether the new SID can inherit resource limits from the old
2271          * SID.  If not, reset all soft limits to the lower of the current
2272          * task's hard limit and the init task's soft limit.
2273          *
2274          * Note that the setting of hard limits (even to lower them) can be
2275          * controlled by the setrlimit check.  The inclusion of the init task's
2276          * soft limit into the computation is to avoid resetting soft limits
2277          * higher than the default soft limit for cases where the default is
2278          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2279          */
2280         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2281                           PROCESS__RLIMITINH, NULL);
2282         if (rc) {
2283                 /* protect against do_prlimit() */
2284                 task_lock(current);
2285                 for (i = 0; i < RLIM_NLIMITS; i++) {
2286                         rlim = current->signal->rlim + i;
2287                         initrlim = init_task.signal->rlim + i;
2288                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2289                 }
2290                 task_unlock(current);
2291                 update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2292         }
2293 }
2294
2295 /*
2296  * Clean up the process immediately after the installation of new credentials
2297  * due to exec
2298  */
2299 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2300 {
2301         const struct task_security_struct *tsec = current_security();
2302         struct itimerval itimer;
2303         u32 osid, sid;
2304         int rc, i;
2305
2306         osid = tsec->osid;
2307         sid = tsec->sid;
2308
2309         if (sid == osid)
2310                 return;
2311
2312         /* Check whether the new SID can inherit signal state from the old SID.
2313          * If not, clear itimers to avoid subsequent signal generation and
2314          * flush and unblock signals.
2315          *
2316          * This must occur _after_ the task SID has been updated so that any
2317          * kill done after the flush will be checked against the new SID.
2318          */
2319         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2320         if (rc) {
2321                 memset(&itimer, 0, sizeof itimer);
2322                 for (i = 0; i < 3; i++)
2323                         do_setitimer(i, &itimer, NULL);
2324                 spin_lock_irq(&current->sighand->siglock);
2325                 if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
2326                         __flush_signals(current);
2327                         flush_signal_handlers(current, 1);
2328                         sigemptyset(&current->blocked);
2329                 }
2330                 spin_unlock_irq(&current->sighand->siglock);
2331         }
2332
2333         /* Wake up the parent if it is waiting so that it can recheck
2334          * wait permission to the new task SID. */
2335         read_lock(&tasklist_lock);
2336         __wake_up_parent(current, current->real_parent);
2337         read_unlock(&tasklist_lock);
2338 }
2339
2340 /* superblock security operations */
2341
2342 static int selinux_sb_alloc_security(struct super_block *sb)
2343 {
2344         return superblock_alloc_security(sb);
2345 }
2346
2347 static void selinux_sb_free_security(struct super_block *sb)
2348 {
2349         superblock_free_security(sb);
2350 }
2351
2352 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2353 {
2354         if (plen > olen)
2355                 return 0;
2356
2357         return !memcmp(prefix, option, plen);
2358 }
2359
2360 static inline int selinux_option(char *option, int len)
2361 {
2362         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2363                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2364                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2365                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2366                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2367 }
2368
2369 static inline void take_option(char **to, char *from, int *first, int len)
2370 {
2371         if (!*first) {
2372                 **to = ',';
2373                 *to += 1;
2374         } else
2375                 *first = 0;
2376         memcpy(*to, from, len);
2377         *to += len;
2378 }
2379
2380 static inline void take_selinux_option(char **to, char *from, int *first,
2381                                        int len)
2382 {
2383         int current_size = 0;
2384
2385         if (!*first) {
2386                 **to = '|';
2387                 *to += 1;
2388         } else
2389                 *first = 0;
2390
2391         while (current_size < len) {
2392                 if (*from != '"') {
2393                         **to = *from;
2394                         *to += 1;
2395                 }
2396                 from += 1;
2397                 current_size += 1;
2398         }
2399 }
2400
2401 static int selinux_sb_copy_data(char *orig, char *copy)
2402 {
2403         int fnosec, fsec, rc = 0;
2404         char *in_save, *in_curr, *in_end;
2405         char *sec_curr, *nosec_save, *nosec;
2406         int open_quote = 0;
2407
2408         in_curr = orig;
2409         sec_curr = copy;
2410
2411         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2412         if (!nosec) {
2413                 rc = -ENOMEM;
2414                 goto out;
2415         }
2416
2417         nosec_save = nosec;
2418         fnosec = fsec = 1;
2419         in_save = in_end = orig;
2420
2421         do {
2422                 if (*in_end == '"')
2423                         open_quote = !open_quote;
2424                 if ((*in_end == ',' && open_quote == 0) ||
2425                                 *in_end == '\0') {
2426                         int len = in_end - in_curr;
2427
2428                         if (selinux_option(in_curr, len))
2429                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2430                         else
2431                                 take_option(&nosec, in_curr, &fnosec, len);
2432
2433                         in_curr = in_end + 1;
2434                 }
2435         } while (*in_end++);
2436
2437         strcpy(in_save, nosec_save);
2438         free_page((unsigned long)nosec_save);
2439 out:
2440         return rc;
2441 }
2442
2443 static int selinux_sb_remount(struct super_block *sb, void *data)
2444 {
2445         int rc, i, *flags;
2446         struct security_mnt_opts opts;
2447         char *secdata, **mount_options;
2448         struct superblock_security_struct *sbsec = sb->s_security;
2449
2450         if (!(sbsec->flags & SE_SBINITIALIZED))
2451                 return 0;
2452
2453         if (!data)
2454                 return 0;
2455
2456         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2457                 return 0;
2458
2459         security_init_mnt_opts(&opts);
2460         secdata = alloc_secdata();
2461         if (!secdata)
2462                 return -ENOMEM;
2463         rc = selinux_sb_copy_data(data, secdata);
2464         if (rc)
2465                 goto out_free_secdata;
2466
2467         rc = selinux_parse_opts_str(secdata, &opts);
2468         if (rc)
2469                 goto out_free_secdata;
2470
2471         mount_options = opts.mnt_opts;
2472         flags = opts.mnt_opts_flags;
2473
2474         for (i = 0; i < opts.num_mnt_opts; i++) {
2475                 u32 sid;
2476                 size_t len;
2477
2478                 if (flags[i] == SBLABEL_MNT)
2479                         continue;
2480                 len = strlen(mount_options[i]);
2481                 rc = security_context_to_sid(mount_options[i], len, &sid);
2482                 if (rc) {
2483                         printk(KERN_WARNING "SELinux: security_context_to_sid"
2484                                "(%s) failed for (dev %s, type "SB_TYPE_FMT") errno=%d\n",
2485                                mount_options[i], sb->s_id, SB_TYPE_ARGS(sb), rc);
2486                         goto out_free_opts;
2487                 }
2488                 rc = -EINVAL;
2489                 switch (flags[i]) {
2490                 case FSCONTEXT_MNT:
2491                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2492                                 goto out_bad_option;
2493                         break;
2494                 case CONTEXT_MNT:
2495                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2496                                 goto out_bad_option;
2497                         break;
2498                 case ROOTCONTEXT_MNT: {
2499                         struct inode_security_struct *root_isec;
2500                         root_isec = sb->s_root->d_inode->i_security;
2501
2502                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2503                                 goto out_bad_option;
2504                         break;
2505                 }
2506                 case DEFCONTEXT_MNT:
2507                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2508                                 goto out_bad_option;
2509                         break;
2510                 default:
2511                         goto out_free_opts;
2512                 }
2513         }
2514
2515         rc = 0;
2516 out_free_opts:
2517         security_free_mnt_opts(&opts);
2518 out_free_secdata:
2519         free_secdata(secdata);
2520         return rc;
2521 out_bad_option:
2522         printk(KERN_WARNING "SELinux: unable to change security options "
2523                "during remount (dev %s, type "SB_TYPE_FMT")\n", sb->s_id,
2524                SB_TYPE_ARGS(sb));
2525         goto out_free_opts;
2526 }
2527
2528 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2529 {
2530         const struct cred *cred = current_cred();
2531         struct common_audit_data ad;
2532         int rc;
2533
2534         rc = superblock_doinit(sb, data);
2535         if (rc)
2536                 return rc;
2537
2538         /* Allow all mounts performed by the kernel */
2539         if (flags & MS_KERNMOUNT)
2540                 return 0;
2541
2542         ad.type = LSM_AUDIT_DATA_DENTRY;
2543         ad.u.dentry = sb->s_root;
2544         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2545 }
2546
2547 static int selinux_sb_statfs(struct dentry *dentry)
2548 {
2549         const struct cred *cred = current_cred();
2550         struct common_audit_data ad;
2551
2552         ad.type = LSM_AUDIT_DATA_DENTRY;
2553         ad.u.dentry = dentry->d_sb->s_root;
2554         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2555 }
2556
2557 static int selinux_mount(const char *dev_name,
2558                          struct path *path,
2559                          const char *type,
2560                          unsigned long flags,
2561                          void *data)
2562 {
2563         const struct cred *cred = current_cred();
2564
2565         if (flags & MS_REMOUNT)
2566                 return superblock_has_perm(cred, path->dentry->d_sb,
2567                                            FILESYSTEM__REMOUNT, NULL);
2568         else
2569                 return path_has_perm(cred, path, FILE__MOUNTON);
2570 }
2571
2572 static int selinux_umount(struct vfsmount *mnt, int flags)
2573 {
2574         const struct cred *cred = current_cred();
2575
2576         return superblock_has_perm(cred, mnt->mnt_sb,
2577                                    FILESYSTEM__UNMOUNT, NULL);
2578 }
2579
2580 /* inode security operations */
2581
2582 static int selinux_inode_alloc_security(struct inode *inode)
2583 {
2584         return inode_alloc_security(inode);
2585 }
2586
2587 static void selinux_inode_free_security(struct inode *inode)
2588 {
2589         inode_free_security(inode);
2590 }
2591
2592 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2593                                         struct qstr *name, void **ctx,
2594                                         u32 *ctxlen)
2595 {
2596         const struct cred *cred = current_cred();
2597         struct task_security_struct *tsec;
2598         struct inode_security_struct *dsec;
2599         struct superblock_security_struct *sbsec;
2600         struct inode *dir = dentry->d_parent->d_inode;
2601         u32 newsid;
2602         int rc;
2603
2604         tsec = cred->security;
2605         dsec = dir->i_security;
2606         sbsec = dir->i_sb->s_security;
2607
2608         if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) {
2609                 newsid = tsec->create_sid;
2610         } else {
2611                 rc = security_transition_sid(tsec->sid, dsec->sid,
2612                                              inode_mode_to_security_class(mode),
2613                                              name,
2614                                              &newsid);
2615                 if (rc) {
2616                         printk(KERN_WARNING
2617                                 "%s: security_transition_sid failed, rc=%d\n",
2618                                __func__, -rc);
2619                         return rc;
2620                 }
2621         }
2622
2623         return security_sid_to_context(newsid, (char **)ctx, ctxlen);
2624 }
2625
2626 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2627                                        const struct qstr *qstr,
2628                                        const char **name,
2629                                        void **value, size_t *len)
2630 {
2631         const struct task_security_struct *tsec = current_security();
2632         struct inode_security_struct *dsec;
2633         struct superblock_security_struct *sbsec;
2634         u32 sid, newsid, clen;
2635         int rc;
2636         char *context;
2637
2638         dsec = dir->i_security;
2639         sbsec = dir->i_sb->s_security;
2640
2641         sid = tsec->sid;
2642         newsid = tsec->create_sid;
2643
2644         if ((sbsec->flags & SE_SBINITIALIZED) &&
2645             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT))
2646                 newsid = sbsec->mntpoint_sid;
2647         else if (!newsid || !(sbsec->flags & SBLABEL_MNT)) {
2648                 rc = security_transition_sid(sid, dsec->sid,
2649                                              inode_mode_to_security_class(inode->i_mode),
2650                                              qstr, &newsid);
2651                 if (rc) {
2652                         printk(KERN_WARNING "%s:  "
2653                                "security_transition_sid failed, rc=%d (dev=%s "
2654                                "ino=%ld)\n",
2655                                __func__,
2656                                -rc, inode->i_sb->s_id, inode->i_ino);
2657                         return rc;
2658                 }
2659         }
2660
2661         /* Possibly defer initialization to selinux_complete_init. */
2662         if (sbsec->flags & SE_SBINITIALIZED) {
2663                 struct inode_security_struct *isec = inode->i_security;
2664                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2665                 isec->sid = newsid;
2666                 isec->initialized = 1;
2667         }
2668
2669         if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2670                 return -EOPNOTSUPP;
2671
2672         if (name)
2673                 *name = XATTR_SELINUX_SUFFIX;
2674
2675         if (value && len) {
2676                 rc = security_sid_to_context_force(newsid, &context, &clen);
2677                 if (rc)
2678                         return rc;
2679                 *value = context;
2680                 *len = clen;
2681         }
2682
2683         return 0;
2684 }
2685
2686 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2687 {
2688         return may_create(dir, dentry, SECCLASS_FILE);
2689 }
2690
2691 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2692 {
2693         return may_link(dir, old_dentry, MAY_LINK);
2694 }
2695
2696 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2697 {
2698         return may_link(dir, dentry, MAY_UNLINK);
2699 }
2700
2701 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2702 {
2703         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2704 }
2705
2706 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2707 {
2708         return may_create(dir, dentry, SECCLASS_DIR);
2709 }
2710
2711 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2712 {
2713         return may_link(dir, dentry, MAY_RMDIR);
2714 }
2715
2716 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2717 {
2718         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2719 }
2720
2721 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2722                                 struct inode *new_inode, struct dentry *new_dentry)
2723 {
2724         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2725 }
2726
2727 static int selinux_inode_readlink(struct dentry *dentry)
2728 {
2729         const struct cred *cred = current_cred();
2730
2731         return dentry_has_perm(cred, dentry, FILE__READ);
2732 }
2733
2734 static int selinux_inode_follow_link(struct dentry *dentry, struct nameidata *nameidata)
2735 {
2736         const struct cred *cred = current_cred();
2737
2738         return dentry_has_perm(cred, dentry, FILE__READ);
2739 }
2740
2741 static noinline int audit_inode_permission(struct inode *inode,
2742                                            u32 perms, u32 audited, u32 denied,
2743                                            unsigned flags)
2744 {
2745         struct common_audit_data ad;
2746         struct inode_security_struct *isec = inode->i_security;
2747         int rc;
2748
2749         ad.type = LSM_AUDIT_DATA_INODE;
2750         ad.u.inode = inode;
2751
2752         rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
2753                             audited, denied, &ad, flags);
2754         if (rc)
2755                 return rc;
2756         return 0;
2757 }
2758
2759 static int selinux_inode_permission(struct inode *inode, int mask)
2760 {
2761         const struct cred *cred = current_cred();
2762         u32 perms;
2763         bool from_access;
2764         unsigned flags = mask & MAY_NOT_BLOCK;
2765         struct inode_security_struct *isec;
2766         u32 sid;
2767         struct av_decision avd;
2768         int rc, rc2;
2769         u32 audited, denied;
2770
2771         from_access = mask & MAY_ACCESS;
2772         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
2773
2774         /* No permission to check.  Existence test. */
2775         if (!mask)
2776                 return 0;
2777
2778         validate_creds(cred);
2779
2780         if (unlikely(IS_PRIVATE(inode)))
2781                 return 0;
2782
2783         perms = file_mask_to_av(inode->i_mode, mask);
2784
2785         sid = cred_sid(cred);
2786         isec = inode->i_security;
2787
2788         rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
2789         audited = avc_audit_required(perms, &avd, rc,
2790                                      from_access ? FILE__AUDIT_ACCESS : 0,
2791                                      &denied);
2792         if (likely(!audited))
2793                 return rc;
2794
2795         rc2 = audit_inode_permission(inode, perms, audited, denied, flags);
2796         if (rc2)
2797                 return rc2;
2798         return rc;
2799 }
2800
2801 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
2802 {
2803         const struct cred *cred = current_cred();
2804         unsigned int ia_valid = iattr->ia_valid;
2805         __u32 av = FILE__WRITE;
2806
2807         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
2808         if (ia_valid & ATTR_FORCE) {
2809                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
2810                               ATTR_FORCE);
2811                 if (!ia_valid)
2812                         return 0;
2813         }
2814
2815         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
2816                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
2817                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
2818
2819         if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE))
2820                 av |= FILE__OPEN;
2821
2822         return dentry_has_perm(cred, dentry, av);
2823 }
2824
2825 static int selinux_inode_getattr(struct vfsmount *mnt, struct dentry *dentry)
2826 {
2827         const struct cred *cred = current_cred();
2828         struct path path;
2829
2830         path.dentry = dentry;
2831         path.mnt = mnt;
2832
2833         return path_has_perm(cred, &path, FILE__GETATTR);
2834 }
2835
2836 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
2837 {
2838         const struct cred *cred = current_cred();
2839
2840         if (!strncmp(name, XATTR_SECURITY_PREFIX,
2841                      sizeof XATTR_SECURITY_PREFIX - 1)) {
2842                 if (!strcmp(name, XATTR_NAME_CAPS)) {
2843                         if (!capable(CAP_SETFCAP))
2844                                 return -EPERM;
2845                 } else if (!capable(CAP_SYS_ADMIN)) {
2846                         /* A different attribute in the security namespace.
2847                            Restrict to administrator. */
2848                         return -EPERM;
2849                 }
2850         }
2851
2852         /* Not an attribute we recognize, so just check the
2853            ordinary setattr permission. */
2854         return dentry_has_perm(cred, dentry, FILE__SETATTR);
2855 }
2856
2857 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
2858                                   const void *value, size_t size, int flags)
2859 {
2860         struct inode *inode = dentry->d_inode;
2861         struct inode_security_struct *isec = inode->i_security;
2862         struct superblock_security_struct *sbsec;
2863         struct common_audit_data ad;
2864         u32 newsid, sid = current_sid();
2865         int rc = 0;
2866
2867         if (strcmp(name, XATTR_NAME_SELINUX))
2868                 return selinux_inode_setotherxattr(dentry, name);
2869
2870         sbsec = inode->i_sb->s_security;
2871         if (!(sbsec->flags & SBLABEL_MNT))
2872                 return -EOPNOTSUPP;
2873
2874         if (!inode_owner_or_capable(inode))
2875                 return -EPERM;
2876
2877         ad.type = LSM_AUDIT_DATA_DENTRY;
2878         ad.u.dentry = dentry;
2879
2880         rc = avc_has_perm(sid, isec->sid, isec->sclass,
2881                           FILE__RELABELFROM, &ad);
2882         if (rc)
2883                 return rc;
2884
2885         rc = security_context_to_sid(value, size, &newsid);
2886         if (rc == -EINVAL) {
2887                 if (!capable(CAP_MAC_ADMIN)) {
2888                         struct audit_buffer *ab;
2889                         size_t audit_size;
2890                         const char *str;
2891
2892                         /* We strip a nul only if it is at the end, otherwise the
2893                          * context contains a nul and we should audit that */
2894                         if (value) {
2895                                 str = value;
2896                                 if (str[size - 1] == '\0')
2897                                         audit_size = size - 1;
2898                                 else
2899                                         audit_size = size;
2900                         } else {
2901                                 str = "";
2902                                 audit_size = 0;
2903                         }
2904                         ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
2905                         audit_log_format(ab, "op=setxattr invalid_context=");
2906                         audit_log_n_untrustedstring(ab, value, audit_size);
2907                         audit_log_end(ab);
2908
2909                         return rc;
2910                 }
2911                 rc = security_context_to_sid_force(value, size, &newsid);
2912         }
2913         if (rc)
2914                 return rc;
2915
2916         rc = avc_has_perm(sid, newsid, isec->sclass,
2917                           FILE__RELABELTO, &ad);
2918         if (rc)
2919                 return rc;
2920
2921         rc = security_validate_transition(isec->sid, newsid, sid,
2922                                           isec->sclass);
2923         if (rc)
2924                 return rc;
2925
2926         return avc_has_perm(newsid,
2927                             sbsec->sid,
2928                             SECCLASS_FILESYSTEM,
2929                             FILESYSTEM__ASSOCIATE,
2930                             &ad);
2931 }
2932
2933 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
2934                                         const void *value, size_t size,
2935                                         int flags)
2936 {
2937         struct inode *inode = dentry->d_inode;
2938         struct inode_security_struct *isec = inode->i_security;
2939         u32 newsid;
2940         int rc;
2941
2942         if (strcmp(name, XATTR_NAME_SELINUX)) {
2943                 /* Not an attribute we recognize, so nothing to do. */
2944                 return;
2945         }
2946
2947         rc = security_context_to_sid_force(value, size, &newsid);
2948         if (rc) {
2949                 printk(KERN_ERR "SELinux:  unable to map context to SID"
2950                        "for (%s, %lu), rc=%d\n",
2951                        inode->i_sb->s_id, inode->i_ino, -rc);
2952                 return;
2953         }
2954
2955         isec->sclass = inode_mode_to_security_class(inode->i_mode);
2956         isec->sid = newsid;
2957         isec->initialized = 1;
2958
2959         return;
2960 }
2961
2962 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
2963 {
2964         const struct cred *cred = current_cred();
2965
2966         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2967 }
2968
2969 static int selinux_inode_listxattr(struct dentry *dentry)
2970 {
2971         const struct cred *cred = current_cred();
2972
2973         return dentry_has_perm(cred, dentry, FILE__GETATTR);
2974 }
2975
2976 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
2977 {
2978         if (strcmp(name, XATTR_NAME_SELINUX))
2979                 return selinux_inode_setotherxattr(dentry, name);
2980
2981         /* No one is allowed to remove a SELinux security label.
2982            You can change the label, but all data must be labeled. */
2983         return -EACCES;
2984 }
2985
2986 /*
2987  * Copy the inode security context value to the user.
2988  *
2989  * Permission check is handled by selinux_inode_getxattr hook.
2990  */
2991 static int selinux_inode_getsecurity(const struct inode *inode, const char *name, void **buffer, bool alloc)
2992 {
2993         u32 size;
2994         int error;
2995         char *context = NULL;
2996         struct inode_security_struct *isec = inode->i_security;
2997
2998         if (strcmp(name, XATTR_SELINUX_SUFFIX))
2999                 return -EOPNOTSUPP;
3000
3001         /*
3002          * If the caller has CAP_MAC_ADMIN, then get the raw context
3003          * value even if it is not defined by current policy; otherwise,
3004          * use the in-core value under current policy.
3005          * Use the non-auditing forms of the permission checks since
3006          * getxattr may be called by unprivileged processes commonly
3007          * and lack of permission just means that we fall back to the
3008          * in-core context value, not a denial.
3009          */
3010         error = selinux_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3011                                 SECURITY_CAP_NOAUDIT);
3012         if (!error)
3013                 error = security_sid_to_context_force(isec->sid, &context,
3014                                                       &size);
3015         else
3016                 error = security_sid_to_context(isec->sid, &context, &size);
3017         if (error)
3018                 return error;
3019         error = size;
3020         if (alloc) {
3021                 *buffer = context;
3022                 goto out_nofree;
3023         }
3024         kfree(context);
3025 out_nofree:
3026         return error;
3027 }
3028
3029 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3030                                      const void *value, size_t size, int flags)
3031 {
3032         struct inode_security_struct *isec = inode->i_security;
3033         u32 newsid;
3034         int rc;
3035
3036         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3037                 return -EOPNOTSUPP;
3038
3039         if (!value || !size)
3040                 return -EACCES;
3041
3042         rc = security_context_to_sid((void *)value, size, &newsid);
3043         if (rc)
3044                 return rc;
3045
3046         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3047         isec->sid = newsid;
3048         isec->initialized = 1;
3049         return 0;
3050 }
3051
3052 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3053 {
3054         const int len = sizeof(XATTR_NAME_SELINUX);
3055         if (buffer && len <= buffer_size)
3056                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3057         return len;
3058 }
3059
3060 static void selinux_inode_getsecid(const struct inode *inode, u32 *secid)
3061 {
3062         struct inode_security_struct *isec = inode->i_security;
3063         *secid = isec->sid;
3064 }
3065
3066 /* file security operations */
3067
3068 static int selinux_revalidate_file_permission(struct file *file, int mask)
3069 {
3070         const struct cred *cred = current_cred();
3071         struct inode *inode = file_inode(file);
3072
3073         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3074         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3075                 mask |= MAY_APPEND;
3076
3077         return file_has_perm(cred, file,
3078                              file_mask_to_av(inode->i_mode, mask));
3079 }
3080
3081 static int selinux_file_permission(struct file *file, int mask)
3082 {
3083         struct inode *inode = file_inode(file);
3084         struct file_security_struct *fsec = file->f_security;
3085         struct inode_security_struct *isec = inode->i_security;
3086         u32 sid = current_sid();
3087
3088         if (!mask)
3089                 /* No permission to check.  Existence test. */
3090                 return 0;
3091
3092         if (sid == fsec->sid && fsec->isid == isec->sid &&
3093             fsec->pseqno == avc_policy_seqno())
3094                 /* No change since file_open check. */
3095                 return 0;
3096
3097         return selinux_revalidate_file_permission(file, mask);
3098 }
3099
3100 static int selinux_file_alloc_security(struct file *file)
3101 {
3102         return file_alloc_security(file);
3103 }
3104
3105 static void selinux_file_free_security(struct file *file)
3106 {
3107         file_free_security(file);
3108 }
3109
3110 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3111                               unsigned long arg)
3112 {
3113         const struct cred *cred = current_cred();
3114         int error = 0;
3115
3116         switch (cmd) {
3117         case FIONREAD:
3118         /* fall through */
3119         case FIBMAP:
3120         /* fall through */
3121         case FIGETBSZ:
3122         /* fall through */
3123         case FS_IOC_GETFLAGS:
3124         /* fall through */
3125         case FS_IOC_GETVERSION:
3126                 error = file_has_perm(cred, file, FILE__GETATTR);
3127                 break;
3128
3129         case FS_IOC_SETFLAGS:
3130         /* fall through */
3131         case FS_IOC_SETVERSION:
3132                 error = file_has_perm(cred, file, FILE__SETATTR);
3133                 break;
3134
3135         /* sys_ioctl() checks */
3136         case FIONBIO:
3137         /* fall through */
3138         case FIOASYNC:
3139                 error = file_has_perm(cred, file, 0);
3140                 break;
3141
3142         case KDSKBENT:
3143         case KDSKBSENT:
3144                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3145                                             SECURITY_CAP_AUDIT);
3146                 break;
3147
3148         /* default case assumes that the command will go
3149          * to the file's ioctl() function.
3150          */
3151         default:
3152                 error = file_has_perm(cred, file, FILE__IOCTL);
3153         }
3154         return error;
3155 }
3156
3157 static int default_noexec;
3158
3159 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3160 {
3161         const struct cred *cred = current_cred();
3162         int rc = 0;
3163
3164         if (default_noexec &&
3165             (prot & PROT_EXEC) && (!file || (!shared && (prot & PROT_WRITE)))) {
3166                 /*
3167                  * We are making executable an anonymous mapping or a
3168                  * private file mapping that will also be writable.
3169                  * This has an additional check.
3170                  */
3171                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3172                 if (rc)
3173                         goto error;
3174         }
3175
3176         if (file) {
3177                 /* read access is always possible with a mapping */
3178                 u32 av = FILE__READ;
3179
3180                 /* write access only matters if the mapping is shared */
3181                 if (shared && (prot & PROT_WRITE))
3182                         av |= FILE__WRITE;
3183
3184                 if (prot & PROT_EXEC)
3185                         av |= FILE__EXECUTE;
3186
3187                 return file_has_perm(cred, file, av);
3188         }
3189
3190 error:
3191         return rc;
3192 }
3193
3194 static int selinux_mmap_addr(unsigned long addr)
3195 {
3196         int rc = 0;
3197         u32 sid = current_sid();
3198
3199         /*
3200          * notice that we are intentionally putting the SELinux check before
3201          * the secondary cap_file_mmap check.  This is such a likely attempt
3202          * at bad behaviour/exploit that we always want to get the AVC, even
3203          * if DAC would have also denied the operation.
3204          */
3205         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3206                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3207                                   MEMPROTECT__MMAP_ZERO, NULL);
3208                 if (rc)
3209                         return rc;
3210         }
3211
3212         /* do DAC check on address space usage */
3213         return cap_mmap_addr(addr);
3214 }
3215
3216 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3217                              unsigned long prot, unsigned long flags)
3218 {
3219         if (selinux_checkreqprot)
3220                 prot = reqprot;
3221
3222         return file_map_prot_check(file, prot,
3223                                    (flags & MAP_TYPE) == MAP_SHARED);
3224 }
3225
3226 static int selinux_file_mprotect(struct vm_area_struct *vma,
3227                                  unsigned long reqprot,
3228                                  unsigned long prot)
3229 {
3230         const struct cred *cred = current_cred();
3231
3232         if (selinux_checkreqprot)
3233                 prot = reqprot;
3234
3235         if (default_noexec &&
3236             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3237                 int rc = 0;
3238                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3239                     vma->vm_end <= vma->vm_mm->brk) {
3240                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3241                 } else if (!vma->vm_file &&
3242                            vma->vm_start <= vma->vm_mm->start_stack &&
3243                            vma->vm_end >= vma->vm_mm->start_stack) {
3244                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3245                 } else if (vma->vm_file && vma->anon_vma) {
3246                         /*
3247                          * We are making executable a file mapping that has
3248                          * had some COW done. Since pages might have been
3249                          * written, check ability to execute the possibly
3250                          * modified content.  This typically should only
3251                          * occur for text relocations.
3252                          */
3253                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3254                 }
3255                 if (rc)
3256                         return rc;
3257         }
3258
3259         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3260 }
3261
3262 static int selinux_file_lock(struct file *file, unsigned int cmd)
3263 {
3264         const struct cred *cred = current_cred();
3265
3266         return file_has_perm(cred, file, FILE__LOCK);
3267 }
3268
3269 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3270                               unsigned long arg)
3271 {
3272         const struct cred *cred = current_cred();
3273         int err = 0;
3274
3275         switch (cmd) {
3276         case F_SETFL:
3277                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3278                         err = file_has_perm(cred, file, FILE__WRITE);
3279                         break;
3280                 }
3281                 /* fall through */
3282         case F_SETOWN:
3283         case F_SETSIG:
3284         case F_GETFL:
3285         case F_GETOWN:
3286         case F_GETSIG:
3287         case F_GETOWNER_UIDS:
3288                 /* Just check FD__USE permission */
3289                 err = file_has_perm(cred, file, 0);
3290                 break;
3291         case F_GETLK:
3292         case F_SETLK:
3293         case F_SETLKW:
3294 #if BITS_PER_LONG == 32
3295         case F_GETLK64:
3296         case F_SETLK64:
3297         case F_SETLKW64:
3298 #endif
3299                 err = file_has_perm(cred, file, FILE__LOCK);
3300                 break;
3301         }
3302
3303         return err;
3304 }
3305
3306 static int selinux_file_set_fowner(struct file *file)
3307 {
3308         struct file_security_struct *fsec;
3309
3310         fsec = file->f_security;
3311         fsec->fown_sid = current_sid();
3312
3313         return 0;
3314 }
3315
3316 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3317                                        struct fown_struct *fown, int signum)
3318 {
3319         struct file *file;
3320         u32 sid = task_sid(tsk);
3321         u32 perm;
3322         struct file_security_struct *fsec;
3323
3324         /* struct fown_struct is never outside the context of a struct file */
3325         file = container_of(fown, struct file, f_owner);
3326
3327         fsec = file->f_security;
3328
3329         if (!signum)
3330                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3331         else
3332                 perm = signal_to_av(signum);
3333
3334         return avc_has_perm(fsec->fown_sid, sid,
3335                             SECCLASS_PROCESS, perm, NULL);
3336 }
3337
3338 static int selinux_file_receive(struct file *file)
3339 {
3340         const struct cred *cred = current_cred();
3341
3342         return file_has_perm(cred, file, file_to_av(file));
3343 }
3344
3345 static int selinux_file_open(struct file *file, const struct cred *cred)
3346 {
3347         struct file_security_struct *fsec;
3348         struct inode_security_struct *isec;
3349
3350         fsec = file->f_security;
3351         isec = file_inode(file)->i_security;
3352         /*
3353          * Save inode label and policy sequence number
3354          * at open-time so that selinux_file_permission
3355          * can determine whether revalidation is necessary.
3356          * Task label is already saved in the file security
3357          * struct as its SID.
3358          */
3359         fsec->isid = isec->sid;
3360         fsec->pseqno = avc_policy_seqno();
3361         /*
3362          * Since the inode label or policy seqno may have changed
3363          * between the selinux_inode_permission check and the saving
3364          * of state above, recheck that access is still permitted.
3365          * Otherwise, access might never be revalidated against the
3366          * new inode label or new policy.
3367          * This check is not redundant - do not remove.
3368          */
3369         return file_path_has_perm(cred, file, open_file_to_av(file));
3370 }
3371
3372 /* task security operations */
3373
3374 static int selinux_task_create(unsigned long clone_flags)
3375 {
3376         return current_has_perm(current, PROCESS__FORK);
3377 }
3378
3379 /*
3380  * allocate the SELinux part of blank credentials
3381  */
3382 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3383 {
3384         struct task_security_struct *tsec;
3385
3386         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3387         if (!tsec)
3388                 return -ENOMEM;
3389
3390         cred->security = tsec;
3391         return 0;
3392 }
3393
3394 /*
3395  * detach and free the LSM part of a set of credentials
3396  */
3397 static void selinux_cred_free(struct cred *cred)
3398 {
3399         struct task_security_struct *tsec = cred->security;
3400
3401         /*
3402          * cred->security == NULL if security_cred_alloc_blank() or
3403          * security_prepare_creds() returned an error.
3404          */
3405         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3406         cred->security = (void *) 0x7UL;
3407         kfree(tsec);
3408 }
3409
3410 /*
3411  * prepare a new set of credentials for modification
3412  */
3413 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3414                                 gfp_t gfp)
3415 {
3416         const struct task_security_struct *old_tsec;
3417         struct task_security_struct *tsec;
3418
3419         old_tsec = old->security;
3420
3421         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3422         if (!tsec)
3423                 return -ENOMEM;
3424
3425         new->security = tsec;
3426         return 0;
3427 }
3428
3429 /*
3430  * transfer the SELinux data to a blank set of creds
3431  */
3432 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3433 {
3434         const struct task_security_struct *old_tsec = old->security;
3435         struct task_security_struct *tsec = new->security;
3436
3437         *tsec = *old_tsec;
3438 }
3439
3440 /*
3441  * set the security data for a kernel service
3442  * - all the creation contexts are set to unlabelled
3443  */
3444 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3445 {
3446         struct task_security_struct *tsec = new->security;
3447         u32 sid = current_sid();
3448         int ret;
3449
3450         ret = avc_has_perm(sid, secid,
3451                            SECCLASS_KERNEL_SERVICE,
3452                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3453                            NULL);
3454         if (ret == 0) {
3455                 tsec->sid = secid;
3456                 tsec->create_sid = 0;
3457                 tsec->keycreate_sid = 0;
3458                 tsec->sockcreate_sid = 0;
3459         }
3460         return ret;
3461 }
3462
3463 /*
3464  * set the file creation context in a security record to the same as the
3465  * objective context of the specified inode
3466  */
3467 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3468 {
3469         struct inode_security_struct *isec = inode->i_security;
3470         struct task_security_struct *tsec = new->security;
3471         u32 sid = current_sid();
3472         int ret;
3473
3474         ret = avc_has_perm(sid, isec->sid,
3475                            SECCLASS_KERNEL_SERVICE,
3476                            KERNEL_SERVICE__CREATE_FILES_AS,
3477                            NULL);
3478
3479         if (ret == 0)
3480                 tsec->create_sid = isec->sid;
3481         return ret;
3482 }
3483
3484 static int selinux_kernel_module_request(char *kmod_name)
3485 {
3486         u32 sid;
3487         struct common_audit_data ad;
3488
3489         sid = task_sid(current);
3490
3491         ad.type = LSM_AUDIT_DATA_KMOD;
3492         ad.u.kmod_name = kmod_name;
3493
3494         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3495                             SYSTEM__MODULE_REQUEST, &ad);
3496 }
3497
3498 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3499 {
3500         return current_has_perm(p, PROCESS__SETPGID);
3501 }
3502
3503 static int selinux_task_getpgid(struct task_struct *p)
3504 {
3505         return current_has_perm(p, PROCESS__GETPGID);
3506 }
3507
3508 static int selinux_task_getsid(struct task_struct *p)
3509 {
3510         return current_has_perm(p, PROCESS__GETSESSION);
3511 }
3512
3513 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3514 {
3515         *secid = task_sid(p);
3516 }
3517
3518 static int selinux_task_setnice(struct task_struct *p, int nice)
3519 {
3520         int rc;
3521
3522         rc = cap_task_setnice(p, nice);
3523         if (rc)
3524                 return rc;
3525
3526         return current_has_perm(p, PROCESS__SETSCHED);
3527 }
3528
3529 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3530 {
3531         int rc;
3532
3533         rc = cap_task_setioprio(p, ioprio);
3534         if (rc)
3535                 return rc;
3536
3537         return current_has_perm(p, PROCESS__SETSCHED);
3538 }
3539
3540 static int selinux_task_getioprio(struct task_struct *p)
3541 {
3542         return current_has_perm(p, PROCESS__GETSCHED);
3543 }
3544
3545 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3546                 struct rlimit *new_rlim)
3547 {
3548         struct rlimit *old_rlim = p->signal->rlim + resource;
3549
3550         /* Control the ability to change the hard limit (whether
3551            lowering or raising it), so that the hard limit can
3552            later be used as a safe reset point for the soft limit
3553            upon context transitions.  See selinux_bprm_committing_creds. */
3554         if (old_rlim->rlim_max != new_rlim->rlim_max)
3555                 return current_has_perm(p, PROCESS__SETRLIMIT);
3556
3557         return 0;
3558 }
3559
3560 static int selinux_task_setscheduler(struct task_struct *p)
3561 {
3562         int rc;
3563
3564         rc = cap_task_setscheduler(p);
3565         if (rc)
3566                 return rc;
3567
3568         return current_has_perm(p, PROCESS__SETSCHED);
3569 }
3570
3571 static int selinux_task_getscheduler(struct task_struct *p)
3572 {
3573         return current_has_perm(p, PROCESS__GETSCHED);
3574 }
3575
3576 static int selinux_task_movememory(struct task_struct *p)
3577 {
3578         return current_has_perm(p, PROCESS__SETSCHED);
3579 }
3580
3581 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3582                                 int sig, u32 secid)
3583 {
3584         u32 perm;
3585         int rc;
3586
3587         if (!sig)
3588                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3589         else
3590                 perm = signal_to_av(sig);
3591         if (secid)
3592                 rc = avc_has_perm(secid, task_sid(p),
3593                                   SECCLASS_PROCESS, perm, NULL);
3594         else
3595                 rc = current_has_perm(p, perm);
3596         return rc;
3597 }
3598
3599 static int selinux_task_wait(struct task_struct *p)
3600 {
3601         return task_has_perm(p, current, PROCESS__SIGCHLD);
3602 }
3603
3604 static void selinux_task_to_inode(struct task_struct *p,
3605                                   struct inode *inode)
3606 {
3607         struct inode_security_struct *isec = inode->i_security;
3608         u32 sid = task_sid(p);
3609
3610         isec->sid = sid;
3611         isec->initialized = 1;
3612 }
3613
3614 /* Returns error only if unable to parse addresses */
3615 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3616                         struct common_audit_data *ad, u8 *proto)
3617 {
3618         int offset, ihlen, ret = -EINVAL;
3619         struct iphdr _iph, *ih;
3620
3621         offset = skb_network_offset(skb);
3622         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3623         if (ih == NULL)
3624                 goto out;
3625
3626         ihlen = ih->ihl * 4;
3627         if (ihlen < sizeof(_iph))
3628                 goto out;
3629
3630         ad->u.net->v4info.saddr = ih->saddr;
3631         ad->u.net->v4info.daddr = ih->daddr;
3632         ret = 0;
3633
3634         if (proto)
3635                 *proto = ih->protocol;
3636
3637         switch (ih->protocol) {
3638         case IPPROTO_TCP: {
3639                 struct tcphdr _tcph, *th;
3640
3641                 if (ntohs(ih->frag_off) & IP_OFFSET)
3642                         break;
3643
3644                 offset += ihlen;
3645                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3646                 if (th == NULL)
3647                         break;
3648
3649                 ad->u.net->sport = th->source;
3650                 ad->u.net->dport = th->dest;
3651                 break;
3652         }
3653
3654         case IPPROTO_UDP: {
3655                 struct udphdr _udph, *uh;
3656
3657                 if (ntohs(ih->frag_off) & IP_OFFSET)
3658                         break;
3659
3660                 offset += ihlen;
3661                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3662                 if (uh == NULL)
3663                         break;
3664
3665                 ad->u.net->sport = uh->source;
3666                 ad->u.net->dport = uh->dest;
3667                 break;
3668         }
3669
3670         case IPPROTO_DCCP: {
3671                 struct dccp_hdr _dccph, *dh;
3672
3673                 if (ntohs(ih->frag_off) & IP_OFFSET)
3674                         break;
3675
3676                 offset += ihlen;
3677                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3678                 if (dh == NULL)
3679                         break;
3680
3681                 ad->u.net->sport = dh->dccph_sport;
3682                 ad->u.net->dport = dh->dccph_dport;
3683                 break;
3684         }
3685
3686         default:
3687                 break;
3688         }
3689 out:
3690         return ret;
3691 }
3692
3693 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3694
3695 /* Returns error only if unable to parse addresses */
3696 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
3697                         struct common_audit_data *ad, u8 *proto)
3698 {
3699         u8 nexthdr;
3700         int ret = -EINVAL, offset;
3701         struct ipv6hdr _ipv6h, *ip6;
3702         __be16 frag_off;
3703
3704         offset = skb_network_offset(skb);
3705         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
3706         if (ip6 == NULL)
3707                 goto out;
3708
3709         ad->u.net->v6info.saddr = ip6->saddr;
3710         ad->u.net->v6info.daddr = ip6->daddr;
3711         ret = 0;
3712
3713         nexthdr = ip6->nexthdr;
3714         offset += sizeof(_ipv6h);
3715         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
3716         if (offset < 0)
3717                 goto out;
3718
3719         if (proto)
3720                 *proto = nexthdr;
3721
3722         switch (nexthdr) {
3723         case IPPROTO_TCP: {
3724                 struct tcphdr _tcph, *th;
3725
3726                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
3727                 if (th == NULL)
3728                         break;
3729
3730                 ad->u.net->sport = th->source;
3731                 ad->u.net->dport = th->dest;
3732                 break;
3733         }
3734
3735         case IPPROTO_UDP: {
3736                 struct udphdr _udph, *uh;
3737
3738                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
3739                 if (uh == NULL)
3740                         break;
3741
3742                 ad->u.net->sport = uh->source;
3743                 ad->u.net->dport = uh->dest;
3744                 break;
3745         }
3746
3747         case IPPROTO_DCCP: {
3748                 struct dccp_hdr _dccph, *dh;
3749
3750                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
3751                 if (dh == NULL)
3752                         break;
3753
3754                 ad->u.net->sport = dh->dccph_sport;
3755                 ad->u.net->dport = dh->dccph_dport;
3756                 break;
3757         }
3758
3759         /* includes fragments */
3760         default:
3761                 break;
3762         }
3763 out:
3764         return ret;
3765 }
3766
3767 #endif /* IPV6 */
3768
3769 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
3770                              char **_addrp, int src, u8 *proto)
3771 {
3772         char *addrp;
3773         int ret;
3774
3775         switch (ad->u.net->family) {
3776         case PF_INET:
3777                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
3778                 if (ret)
3779                         goto parse_error;
3780                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
3781                                        &ad->u.net->v4info.daddr);
3782                 goto okay;
3783
3784 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
3785         case PF_INET6:
3786                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
3787                 if (ret)
3788                         goto parse_error;
3789                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
3790                                        &ad->u.net->v6info.daddr);
3791                 goto okay;
3792 #endif  /* IPV6 */
3793         default:
3794                 addrp = NULL;
3795                 goto okay;
3796         }
3797
3798 parse_error:
3799         printk(KERN_WARNING
3800                "SELinux: failure in selinux_parse_skb(),"
3801                " unable to parse packet\n");
3802         return ret;
3803
3804 okay:
3805         if (_addrp)
3806                 *_addrp = addrp;
3807         return 0;
3808 }
3809
3810 /**
3811  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
3812  * @skb: the packet
3813  * @family: protocol family
3814  * @sid: the packet's peer label SID
3815  *
3816  * Description:
3817  * Check the various different forms of network peer labeling and determine
3818  * the peer label/SID for the packet; most of the magic actually occurs in
3819  * the security server function security_net_peersid_cmp().  The function
3820  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
3821  * or -EACCES if @sid is invalid due to inconsistencies with the different
3822  * peer labels.
3823  *
3824  */
3825 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
3826 {
3827         int err;
3828         u32 xfrm_sid;
3829         u32 nlbl_sid;
3830         u32 nlbl_type;
3831
3832         err = selinux_skb_xfrm_sid(skb, &xfrm_sid);
3833         if (unlikely(err))
3834                 return -EACCES;
3835         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
3836         if (unlikely(err))
3837                 return -EACCES;
3838
3839         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
3840         if (unlikely(err)) {
3841                 printk(KERN_WARNING
3842                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
3843                        " unable to determine packet's peer label\n");
3844                 return -EACCES;
3845         }
3846
3847         return 0;
3848 }
3849
3850 /* socket security operations */
3851
3852 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
3853                                  u16 secclass, u32 *socksid)
3854 {
3855         if (tsec->sockcreate_sid > SECSID_NULL) {
3856                 *socksid = tsec->sockcreate_sid;
3857                 return 0;
3858         }
3859
3860         return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
3861                                        socksid);
3862 }
3863
3864 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
3865 {
3866         struct sk_security_struct *sksec = sk->sk_security;
3867         struct common_audit_data ad;
3868         struct lsm_network_audit net = {0,};
3869         u32 tsid = task_sid(task);
3870
3871         if (sksec->sid == SECINITSID_KERNEL)
3872                 return 0;
3873
3874         ad.type = LSM_AUDIT_DATA_NET;
3875         ad.u.net = &net;
3876         ad.u.net->sk = sk;
3877
3878         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
3879 }
3880
3881 static int selinux_socket_create(int family, int type,
3882                                  int protocol, int kern)
3883 {
3884         const struct task_security_struct *tsec = current_security();
3885         u32 newsid;
3886         u16 secclass;
3887         int rc;
3888
3889         if (kern)
3890                 return 0;
3891
3892         secclass = socket_type_to_security_class(family, type, protocol);
3893         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
3894         if (rc)
3895                 return rc;
3896
3897         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
3898 }
3899
3900 static int selinux_socket_post_create(struct socket *sock, int family,
3901                                       int type, int protocol, int kern)
3902 {
3903         const struct task_security_struct *tsec = current_security();
3904         struct inode_security_struct *isec = SOCK_INODE(sock)->i_security;
3905         struct sk_security_struct *sksec;
3906         int err = 0;
3907
3908         isec->sclass = socket_type_to_security_class(family, type, protocol);
3909
3910         if (kern)
3911                 isec->sid = SECINITSID_KERNEL;
3912         else {
3913                 err = socket_sockcreate_sid(tsec, isec->sclass, &(isec->sid));
3914                 if (err)
3915                         return err;
3916         }
3917
3918         isec->initialized = 1;
3919
3920         if (sock->sk) {
3921                 sksec = sock->sk->sk_security;
3922                 sksec->sid = isec->sid;
3923                 sksec->sclass = isec->sclass;
3924                 err = selinux_netlbl_socket_post_create(sock->sk, family);
3925         }
3926
3927         return err;
3928 }
3929
3930 /* Range of port numbers used to automatically bind.
3931    Need to determine whether we should perform a name_bind
3932    permission check between the socket and the port number. */
3933
3934 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
3935 {
3936         struct sock *sk = sock->sk;
3937         u16 family;
3938         int err;
3939
3940         err = sock_has_perm(current, sk, SOCKET__BIND);
3941         if (err)
3942                 goto out;
3943
3944         /*
3945          * If PF_INET or PF_INET6, check name_bind permission for the port.
3946          * Multiple address binding for SCTP is not supported yet: we just
3947          * check the first address now.
3948          */
3949         family = sk->sk_family;
3950         if (family == PF_INET || family == PF_INET6) {
3951                 char *addrp;
3952                 struct sk_security_struct *sksec = sk->sk_security;
3953                 struct common_audit_data ad;
3954                 struct lsm_network_audit net = {0,};
3955                 struct sockaddr_in *addr4 = NULL;
3956                 struct sockaddr_in6 *addr6 = NULL;
3957                 unsigned short snum;
3958                 u32 sid, node_perm;
3959
3960                 if (family == PF_INET) {
3961                         addr4 = (struct sockaddr_in *)address;
3962                         snum = ntohs(addr4->sin_port);
3963                         addrp = (char *)&addr4->sin_addr.s_addr;
3964                 } else {
3965                         addr6 = (struct sockaddr_in6 *)address;
3966                         snum = ntohs(addr6->sin6_port);
3967                         addrp = (char *)&addr6->sin6_addr.s6_addr;
3968                 }
3969
3970                 if (snum) {
3971                         int low, high;
3972
3973                         inet_get_local_port_range(&low, &high);
3974
3975                         if (snum < max(PROT_SOCK, low) || snum > high) {
3976                                 err = sel_netport_sid(sk->sk_protocol,
3977                                                       snum, &sid);
3978                                 if (err)
3979                                         goto out;
3980                                 ad.type = LSM_AUDIT_DATA_NET;
3981                                 ad.u.net = &net;
3982                                 ad.u.net->sport = htons(snum);
3983                                 ad.u.net->family = family;
3984                                 err = avc_has_perm(sksec->sid, sid,
3985                                                    sksec->sclass,
3986                                                    SOCKET__NAME_BIND, &ad);
3987                                 if (err)
3988                                         goto out;
3989                         }
3990                 }
3991
3992                 switch (sksec->sclass) {
3993                 case SECCLASS_TCP_SOCKET:
3994                         node_perm = TCP_SOCKET__NODE_BIND;
3995                         break;
3996
3997                 case SECCLASS_UDP_SOCKET:
3998                         node_perm = UDP_SOCKET__NODE_BIND;
3999                         break;
4000
4001                 case SECCLASS_DCCP_SOCKET:
4002                         node_perm = DCCP_SOCKET__NODE_BIND;
4003                         break;
4004
4005                 default:
4006                         node_perm = RAWIP_SOCKET__NODE_BIND;
4007                         break;
4008                 }
4009
4010                 err = sel_netnode_sid(addrp, family, &sid);
4011                 if (err)
4012                         goto out;
4013
4014                 ad.type = LSM_AUDIT_DATA_NET;
4015                 ad.u.net = &net;
4016                 ad.u.net->sport = htons(snum);
4017                 ad.u.net->family = family;
4018
4019                 if (family == PF_INET)
4020                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4021                 else
4022                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4023
4024                 err = avc_has_perm(sksec->sid, sid,
4025                                    sksec->sclass, node_perm, &ad);
4026                 if (err)
4027                         goto out;
4028         }
4029 out:
4030         return err;
4031 }
4032
4033 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
4034 {
4035         struct sock *sk = sock->sk;
4036         struct sk_security_struct *sksec = sk->sk_security;
4037         int err;
4038
4039         err = sock_has_perm(current, sk, SOCKET__CONNECT);
4040         if (err)
4041                 return err;
4042
4043         /*
4044          * If a TCP or DCCP socket, check name_connect permission for the port.
4045          */
4046         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4047             sksec->sclass == SECCLASS_DCCP_SOCKET) {
4048                 struct common_audit_data ad;
4049                 struct lsm_network_audit net = {0,};
4050                 struct sockaddr_in *addr4 = NULL;
4051                 struct sockaddr_in6 *addr6 = NULL;
4052                 unsigned short snum;
4053                 u32 sid, perm;
4054
4055                 if (sk->sk_family == PF_INET) {
4056                         addr4 = (struct sockaddr_in *)address;
4057                         if (addrlen < sizeof(struct sockaddr_in))
4058                                 return -EINVAL;
4059                         snum = ntohs(addr4->sin_port);
4060                 } else {
4061                         addr6 = (struct sockaddr_in6 *)address;
4062                         if (addrlen < SIN6_LEN_RFC2133)
4063                                 return -EINVAL;
4064                         snum = ntohs(addr6->sin6_port);
4065                 }
4066
4067                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4068                 if (err)
4069                         goto out;
4070
4071                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
4072                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
4073
4074                 ad.type = LSM_AUDIT_DATA_NET;
4075                 ad.u.net = &net;
4076                 ad.u.net->dport = htons(snum);
4077                 ad.u.net->family = sk->sk_family;
4078                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4079                 if (err)
4080                         goto out;
4081         }
4082
4083         err = selinux_netlbl_socket_connect(sk, address);
4084
4085 out:
4086         return err;
4087 }
4088
4089 static int selinux_socket_listen(struct socket *sock, int backlog)
4090 {
4091         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
4092 }
4093
4094 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4095 {
4096         int err;
4097         struct inode_security_struct *isec;
4098         struct inode_security_struct *newisec;
4099
4100         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4101         if (err)
4102                 return err;
4103
4104         newisec = SOCK_INODE(newsock)->i_security;
4105
4106         isec = SOCK_INODE(sock)->i_security;
4107         newisec->sclass = isec->sclass;
4108         newisec->sid = isec->sid;
4109         newisec->initialized = 1;
4110
4111         return 0;
4112 }
4113
4114 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4115                                   int size)
4116 {
4117         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4118 }
4119
4120 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4121                                   int size, int flags)
4122 {
4123         return sock_has_perm(current, sock->sk, SOCKET__READ);
4124 }
4125
4126 static int selinux_socket_getsockname(struct socket *sock)
4127 {
4128         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4129 }
4130
4131 static int selinux_socket_getpeername(struct socket *sock)
4132 {
4133         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4134 }
4135
4136 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4137 {
4138         int err;
4139
4140         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4141         if (err)
4142                 return err;
4143
4144         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4145 }
4146
4147 static int selinux_socket_getsockopt(struct socket *sock, int level,
4148                                      int optname)
4149 {
4150         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4151 }
4152
4153 static int selinux_socket_shutdown(struct socket *sock, int how)
4154 {
4155         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4156 }
4157
4158 static int selinux_socket_unix_stream_connect(struct sock *sock,
4159                                               struct sock *other,
4160                                               struct sock *newsk)
4161 {
4162         struct sk_security_struct *sksec_sock = sock->sk_security;
4163         struct sk_security_struct *sksec_other = other->sk_security;
4164         struct sk_security_struct *sksec_new = newsk->sk_security;
4165         struct common_audit_data ad;
4166         struct lsm_network_audit net = {0,};
4167         int err;
4168
4169         ad.type = LSM_AUDIT_DATA_NET;
4170         ad.u.net = &net;
4171         ad.u.net->sk = other;
4172
4173         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4174                            sksec_other->sclass,
4175                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4176         if (err)
4177                 return err;
4178
4179         /* server child socket */
4180         sksec_new->peer_sid = sksec_sock->sid;
4181         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4182                                     &sksec_new->sid);
4183         if (err)
4184                 return err;
4185
4186         /* connecting socket */
4187         sksec_sock->peer_sid = sksec_new->sid;
4188
4189         return 0;
4190 }
4191
4192 static int selinux_socket_unix_may_send(struct socket *sock,
4193                                         struct socket *other)
4194 {
4195         struct sk_security_struct *ssec = sock->sk->sk_security;
4196         struct sk_security_struct *osec = other->sk->sk_security;
4197         struct common_audit_data ad;
4198         struct lsm_network_audit net = {0,};
4199
4200         ad.type = LSM_AUDIT_DATA_NET;
4201         ad.u.net = &net;
4202         ad.u.net->sk = other->sk;
4203
4204         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4205                             &ad);
4206 }
4207
4208 static int selinux_inet_sys_rcv_skb(int ifindex, char *addrp, u16 family,
4209                                     u32 peer_sid,
4210                                     struct common_audit_data *ad)
4211 {
4212         int err;
4213         u32 if_sid;
4214         u32 node_sid;
4215
4216         err = sel_netif_sid(ifindex, &if_sid);
4217         if (err)
4218                 return err;
4219         err = avc_has_perm(peer_sid, if_sid,
4220                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4221         if (err)
4222                 return err;
4223
4224         err = sel_netnode_sid(addrp, family, &node_sid);
4225         if (err)
4226                 return err;
4227         return avc_has_perm(peer_sid, node_sid,
4228                             SECCLASS_NODE, NODE__RECVFROM, ad);
4229 }
4230
4231 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4232                                        u16 family)
4233 {
4234         int err = 0;
4235         struct sk_security_struct *sksec = sk->sk_security;
4236         u32 sk_sid = sksec->sid;
4237         struct common_audit_data ad;
4238         struct lsm_network_audit net = {0,};
4239         char *addrp;
4240
4241         ad.type = LSM_AUDIT_DATA_NET;
4242         ad.u.net = &net;
4243         ad.u.net->netif = skb->skb_iif;
4244         ad.u.net->family = family;
4245         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4246         if (err)
4247                 return err;
4248
4249         if (selinux_secmark_enabled()) {
4250                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4251                                    PACKET__RECV, &ad);
4252                 if (err)
4253                         return err;
4254         }
4255
4256         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4257         if (err)
4258                 return err;
4259         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4260
4261         return err;
4262 }
4263
4264 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4265 {
4266         int err;
4267         struct sk_security_struct *sksec = sk->sk_security;
4268         u16 family = sk->sk_family;
4269         u32 sk_sid = sksec->sid;
4270         struct common_audit_data ad;
4271         struct lsm_network_audit net = {0,};
4272         char *addrp;
4273         u8 secmark_active;
4274         u8 peerlbl_active;
4275
4276         if (family != PF_INET && family != PF_INET6)
4277                 return 0;
4278
4279         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4280         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4281                 family = PF_INET;
4282
4283         /* If any sort of compatibility mode is enabled then handoff processing
4284          * to the selinux_sock_rcv_skb_compat() function to deal with the
4285          * special handling.  We do this in an attempt to keep this function
4286          * as fast and as clean as possible. */
4287         if (!selinux_policycap_netpeer)
4288                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4289
4290         secmark_active = selinux_secmark_enabled();
4291         peerlbl_active = selinux_peerlbl_enabled();
4292         if (!secmark_active && !peerlbl_active)
4293                 return 0;
4294
4295         ad.type = LSM_AUDIT_DATA_NET;
4296         ad.u.net = &net;
4297         ad.u.net->netif = skb->skb_iif;
4298         ad.u.net->family = family;
4299         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4300         if (err)
4301                 return err;
4302
4303         if (peerlbl_active) {
4304                 u32 peer_sid;
4305
4306                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4307                 if (err)
4308                         return err;
4309                 err = selinux_inet_sys_rcv_skb(skb->skb_iif, addrp, family,
4310                                                peer_sid, &ad);
4311                 if (err) {
4312                         selinux_netlbl_err(skb, err, 0);
4313                         return err;
4314                 }
4315                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4316                                    PEER__RECV, &ad);
4317                 if (err)
4318                         selinux_netlbl_err(skb, err, 0);
4319         }
4320
4321         if (secmark_active) {
4322                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4323                                    PACKET__RECV, &ad);
4324                 if (err)
4325                         return err;
4326         }
4327
4328         return err;
4329 }
4330
4331 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4332                                             int __user *optlen, unsigned len)
4333 {
4334         int err = 0;
4335         char *scontext;
4336         u32 scontext_len;
4337         struct sk_security_struct *sksec = sock->sk->sk_security;
4338         u32 peer_sid = SECSID_NULL;
4339
4340         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4341             sksec->sclass == SECCLASS_TCP_SOCKET)
4342                 peer_sid = sksec->peer_sid;
4343         if (peer_sid == SECSID_NULL)
4344                 return -ENOPROTOOPT;
4345
4346         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4347         if (err)
4348                 return err;
4349
4350         if (scontext_len > len) {
4351                 err = -ERANGE;
4352                 goto out_len;
4353         }
4354
4355         if (copy_to_user(optval, scontext, scontext_len))
4356                 err = -EFAULT;
4357
4358 out_len:
4359         if (put_user(scontext_len, optlen))
4360                 err = -EFAULT;
4361         kfree(scontext);
4362         return err;
4363 }
4364
4365 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4366 {
4367         u32 peer_secid = SECSID_NULL;
4368         u16 family;
4369
4370         if (skb && skb->protocol == htons(ETH_P_IP))
4371                 family = PF_INET;
4372         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4373                 family = PF_INET6;
4374         else if (sock)
4375                 family = sock->sk->sk_family;
4376         else
4377                 goto out;
4378
4379         if (sock && family == PF_UNIX)
4380                 selinux_inode_getsecid(SOCK_INODE(sock), &peer_secid);
4381         else if (skb)
4382                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4383
4384 out:
4385         *secid = peer_secid;
4386         if (peer_secid == SECSID_NULL)
4387                 return -EINVAL;
4388         return 0;
4389 }
4390
4391 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4392 {
4393         struct sk_security_struct *sksec;
4394
4395         sksec = kzalloc(sizeof(*sksec), priority);
4396         if (!sksec)
4397                 return -ENOMEM;
4398
4399         sksec->peer_sid = SECINITSID_UNLABELED;
4400         sksec->sid = SECINITSID_UNLABELED;
4401         selinux_netlbl_sk_security_reset(sksec);
4402         sk->sk_security = sksec;
4403
4404         return 0;
4405 }
4406
4407 static void selinux_sk_free_security(struct sock *sk)
4408 {
4409         struct sk_security_struct *sksec = sk->sk_security;
4410
4411         sk->sk_security = NULL;
4412         selinux_netlbl_sk_security_free(sksec);
4413         kfree(sksec);
4414 }
4415
4416 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4417 {
4418         struct sk_security_struct *sksec = sk->sk_security;
4419         struct sk_security_struct *newsksec = newsk->sk_security;
4420
4421         newsksec->sid = sksec->sid;
4422         newsksec->peer_sid = sksec->peer_sid;
4423         newsksec->sclass = sksec->sclass;
4424
4425         selinux_netlbl_sk_security_reset(newsksec);
4426 }
4427
4428 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4429 {
4430         if (!sk)
4431                 *secid = SECINITSID_ANY_SOCKET;
4432         else {
4433                 struct sk_security_struct *sksec = sk->sk_security;
4434
4435                 *secid = sksec->sid;
4436         }
4437 }
4438
4439 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4440 {
4441         struct inode_security_struct *isec = SOCK_INODE(parent)->i_security;
4442         struct sk_security_struct *sksec = sk->sk_security;
4443
4444         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4445             sk->sk_family == PF_UNIX)
4446                 isec->sid = sksec->sid;
4447         sksec->sclass = isec->sclass;
4448 }
4449
4450 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4451                                      struct request_sock *req)
4452 {
4453         struct sk_security_struct *sksec = sk->sk_security;
4454         int err;
4455         u16 family = sk->sk_family;
4456         u32 newsid;
4457         u32 peersid;
4458
4459         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4460         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4461                 family = PF_INET;
4462
4463         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4464         if (err)
4465                 return err;
4466         if (peersid == SECSID_NULL) {
4467                 req->secid = sksec->sid;
4468                 req->peer_secid = SECSID_NULL;
4469         } else {
4470                 err = security_sid_mls_copy(sksec->sid, peersid, &newsid);
4471                 if (err)
4472                         return err;
4473                 req->secid = newsid;
4474                 req->peer_secid = peersid;
4475         }
4476
4477         return selinux_netlbl_inet_conn_request(req, family);
4478 }
4479
4480 static void selinux_inet_csk_clone(struct sock *newsk,
4481                                    const struct request_sock *req)
4482 {
4483         struct sk_security_struct *newsksec = newsk->sk_security;
4484
4485         newsksec->sid = req->secid;
4486         newsksec->peer_sid = req->peer_secid;
4487         /* NOTE: Ideally, we should also get the isec->sid for the
4488            new socket in sync, but we don't have the isec available yet.
4489            So we will wait until sock_graft to do it, by which
4490            time it will have been created and available. */
4491
4492         /* We don't need to take any sort of lock here as we are the only
4493          * thread with access to newsksec */
4494         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4495 }
4496
4497 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4498 {
4499         u16 family = sk->sk_family;
4500         struct sk_security_struct *sksec = sk->sk_security;
4501
4502         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4503         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4504                 family = PF_INET;
4505
4506         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4507 }
4508
4509 static void selinux_skb_owned_by(struct sk_buff *skb, struct sock *sk)
4510 {
4511         skb_set_owner_w(skb, sk);
4512 }
4513
4514 static int selinux_secmark_relabel_packet(u32 sid)
4515 {
4516         const struct task_security_struct *__tsec;
4517         u32 tsid;
4518
4519         __tsec = current_security();
4520         tsid = __tsec->sid;
4521
4522         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4523 }
4524
4525 static void selinux_secmark_refcount_inc(void)
4526 {
4527         atomic_inc(&selinux_secmark_refcount);
4528 }
4529
4530 static void selinux_secmark_refcount_dec(void)
4531 {
4532         atomic_dec(&selinux_secmark_refcount);
4533 }
4534
4535 static void selinux_req_classify_flow(const struct request_sock *req,
4536                                       struct flowi *fl)
4537 {
4538         fl->flowi_secid = req->secid;
4539 }
4540
4541 static int selinux_tun_dev_alloc_security(void **security)
4542 {
4543         struct tun_security_struct *tunsec;
4544
4545         tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
4546         if (!tunsec)
4547                 return -ENOMEM;
4548         tunsec->sid = current_sid();
4549
4550         *security = tunsec;
4551         return 0;
4552 }
4553
4554 static void selinux_tun_dev_free_security(void *security)
4555 {
4556         kfree(security);
4557 }
4558
4559 static int selinux_tun_dev_create(void)
4560 {
4561         u32 sid = current_sid();
4562
4563         /* we aren't taking into account the "sockcreate" SID since the socket
4564          * that is being created here is not a socket in the traditional sense,
4565          * instead it is a private sock, accessible only to the kernel, and
4566          * representing a wide range of network traffic spanning multiple
4567          * connections unlike traditional sockets - check the TUN driver to
4568          * get a better understanding of why this socket is special */
4569
4570         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4571                             NULL);
4572 }
4573
4574 static int selinux_tun_dev_attach_queue(void *security)
4575 {
4576         struct tun_security_struct *tunsec = security;
4577
4578         return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
4579                             TUN_SOCKET__ATTACH_QUEUE, NULL);
4580 }
4581
4582 static int selinux_tun_dev_attach(struct sock *sk, void *security)
4583 {
4584         struct tun_security_struct *tunsec = security;
4585         struct sk_security_struct *sksec = sk->sk_security;
4586
4587         /* we don't currently perform any NetLabel based labeling here and it
4588          * isn't clear that we would want to do so anyway; while we could apply
4589          * labeling without the support of the TUN user the resulting labeled
4590          * traffic from the other end of the connection would almost certainly
4591          * cause confusion to the TUN user that had no idea network labeling
4592          * protocols were being used */
4593
4594         sksec->sid = tunsec->sid;
4595         sksec->sclass = SECCLASS_TUN_SOCKET;
4596
4597         return 0;
4598 }
4599
4600 static int selinux_tun_dev_open(void *security)
4601 {
4602         struct tun_security_struct *tunsec = security;
4603         u32 sid = current_sid();
4604         int err;
4605
4606         err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4607                            TUN_SOCKET__RELABELFROM, NULL);
4608         if (err)
4609                 return err;
4610         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
4611                            TUN_SOCKET__RELABELTO, NULL);
4612         if (err)
4613                 return err;
4614         tunsec->sid = sid;
4615
4616         return 0;
4617 }
4618
4619 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
4620 {
4621         int err = 0;
4622         u32 perm;
4623         struct nlmsghdr *nlh;
4624         struct sk_security_struct *sksec = sk->sk_security;
4625
4626         if (skb->len < NLMSG_HDRLEN) {
4627                 err = -EINVAL;
4628                 goto out;
4629         }
4630         nlh = nlmsg_hdr(skb);
4631
4632         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
4633         if (err) {
4634                 if (err == -EINVAL) {
4635                         audit_log(current->audit_context, GFP_KERNEL, AUDIT_SELINUX_ERR,
4636                                   "SELinux:  unrecognized netlink message"
4637                                   " type=%hu for sclass=%hu\n",
4638                                   nlh->nlmsg_type, sksec->sclass);
4639                         if (!selinux_enforcing || security_get_allow_unknown())
4640                                 err = 0;
4641                 }
4642
4643                 /* Ignore */
4644                 if (err == -ENOENT)
4645                         err = 0;
4646                 goto out;
4647         }
4648
4649         err = sock_has_perm(current, sk, perm);
4650 out:
4651         return err;
4652 }
4653
4654 #ifdef CONFIG_NETFILTER
4655
4656 static unsigned int selinux_ip_forward(struct sk_buff *skb, int ifindex,
4657                                        u16 family)
4658 {
4659         int err;
4660         char *addrp;
4661         u32 peer_sid;
4662         struct common_audit_data ad;
4663         struct lsm_network_audit net = {0,};
4664         u8 secmark_active;
4665         u8 netlbl_active;
4666         u8 peerlbl_active;
4667
4668         if (!selinux_policycap_netpeer)
4669                 return NF_ACCEPT;
4670
4671         secmark_active = selinux_secmark_enabled();
4672         netlbl_active = netlbl_enabled();
4673         peerlbl_active = selinux_peerlbl_enabled();
4674         if (!secmark_active && !peerlbl_active)
4675                 return NF_ACCEPT;
4676
4677         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
4678                 return NF_DROP;
4679
4680         ad.type = LSM_AUDIT_DATA_NET;
4681         ad.u.net = &net;
4682         ad.u.net->netif = ifindex;
4683         ad.u.net->family = family;
4684         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
4685                 return NF_DROP;
4686
4687         if (peerlbl_active) {
4688                 err = selinux_inet_sys_rcv_skb(ifindex, addrp, family,
4689                                                peer_sid, &ad);
4690                 if (err) {
4691                         selinux_netlbl_err(skb, err, 1);
4692                         return NF_DROP;
4693                 }
4694         }
4695
4696         if (secmark_active)
4697                 if (avc_has_perm(peer_sid, skb->secmark,
4698                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
4699                         return NF_DROP;
4700
4701         if (netlbl_active)
4702                 /* we do this in the FORWARD path and not the POST_ROUTING
4703                  * path because we want to make sure we apply the necessary
4704                  * labeling before IPsec is applied so we can leverage AH
4705                  * protection */
4706                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
4707                         return NF_DROP;
4708
4709         return NF_ACCEPT;
4710 }
4711
4712 static unsigned int selinux_ipv4_forward(unsigned int hooknum,
4713                                          struct sk_buff *skb,
4714                                          const struct net_device *in,
4715                                          const struct net_device *out,
4716                                          int (*okfn)(struct sk_buff *))
4717 {
4718         return selinux_ip_forward(skb, in->ifindex, PF_INET);
4719 }
4720
4721 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4722 static unsigned int selinux_ipv6_forward(unsigned int hooknum,
4723                                          struct sk_buff *skb,
4724                                          const struct net_device *in,
4725                                          const struct net_device *out,
4726                                          int (*okfn)(struct sk_buff *))
4727 {
4728         return selinux_ip_forward(skb, in->ifindex, PF_INET6);
4729 }
4730 #endif  /* IPV6 */
4731
4732 static unsigned int selinux_ip_output(struct sk_buff *skb,
4733                                       u16 family)
4734 {
4735         u32 sid;
4736
4737         if (!netlbl_enabled())
4738                 return NF_ACCEPT;
4739
4740         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
4741          * because we want to make sure we apply the necessary labeling
4742          * before IPsec is applied so we can leverage AH protection */
4743         if (skb->sk) {
4744                 struct sk_security_struct *sksec = skb->sk->sk_security;
4745                 sid = sksec->sid;
4746         } else
4747                 sid = SECINITSID_KERNEL;
4748         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
4749                 return NF_DROP;
4750
4751         return NF_ACCEPT;
4752 }
4753
4754 static unsigned int selinux_ipv4_output(unsigned int hooknum,
4755                                         struct sk_buff *skb,
4756                                         const struct net_device *in,
4757                                         const struct net_device *out,
4758                                         int (*okfn)(struct sk_buff *))
4759 {
4760         return selinux_ip_output(skb, PF_INET);
4761 }
4762
4763 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
4764                                                 int ifindex,
4765                                                 u16 family)
4766 {
4767         struct sock *sk = skb->sk;
4768         struct sk_security_struct *sksec;
4769         struct common_audit_data ad;
4770         struct lsm_network_audit net = {0,};
4771         char *addrp;
4772         u8 proto;
4773
4774         if (sk == NULL)
4775                 return NF_ACCEPT;
4776         sksec = sk->sk_security;
4777
4778         ad.type = LSM_AUDIT_DATA_NET;
4779         ad.u.net = &net;
4780         ad.u.net->netif = ifindex;
4781         ad.u.net->family = family;
4782         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
4783                 return NF_DROP;
4784
4785         if (selinux_secmark_enabled())
4786                 if (avc_has_perm(sksec->sid, skb->secmark,
4787                                  SECCLASS_PACKET, PACKET__SEND, &ad))
4788                         return NF_DROP_ERR(-ECONNREFUSED);
4789
4790         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
4791                 return NF_DROP_ERR(-ECONNREFUSED);
4792
4793         return NF_ACCEPT;
4794 }
4795
4796 static unsigned int selinux_ip_postroute(struct sk_buff *skb, int ifindex,
4797                                          u16 family)
4798 {
4799         u32 secmark_perm;
4800         u32 peer_sid;
4801         struct sock *sk;
4802         struct common_audit_data ad;
4803         struct lsm_network_audit net = {0,};
4804         char *addrp;
4805         u8 secmark_active;
4806         u8 peerlbl_active;
4807
4808         /* If any sort of compatibility mode is enabled then handoff processing
4809          * to the selinux_ip_postroute_compat() function to deal with the
4810          * special handling.  We do this in an attempt to keep this function
4811          * as fast and as clean as possible. */
4812         if (!selinux_policycap_netpeer)
4813                 return selinux_ip_postroute_compat(skb, ifindex, family);
4814 #ifdef CONFIG_XFRM
4815         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
4816          * packet transformation so allow the packet to pass without any checks
4817          * since we'll have another chance to perform access control checks
4818          * when the packet is on it's final way out.
4819          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
4820          *       is NULL, in this case go ahead and apply access control. */
4821         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL)
4822                 return NF_ACCEPT;
4823 #endif
4824         secmark_active = selinux_secmark_enabled();
4825         peerlbl_active = selinux_peerlbl_enabled();
4826         if (!secmark_active && !peerlbl_active)
4827                 return NF_ACCEPT;
4828
4829         /* if the packet is being forwarded then get the peer label from the
4830          * packet itself; otherwise check to see if it is from a local
4831          * application or the kernel, if from an application get the peer label
4832          * from the sending socket, otherwise use the kernel's sid */
4833         sk = skb->sk;
4834         if (sk == NULL) {
4835                 if (skb->skb_iif) {
4836                         secmark_perm = PACKET__FORWARD_OUT;
4837                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
4838                                 return NF_DROP;
4839                 } else {
4840                         secmark_perm = PACKET__SEND;
4841                         peer_sid = SECINITSID_KERNEL;
4842                 }
4843         } else {
4844                 struct sk_security_struct *sksec = sk->sk_security;
4845                 peer_sid = sksec->sid;
4846                 secmark_perm = PACKET__SEND;
4847         }
4848
4849         ad.type = LSM_AUDIT_DATA_NET;
4850         ad.u.net = &net;
4851         ad.u.net->netif = ifindex;
4852         ad.u.net->family = family;
4853         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
4854                 return NF_DROP;
4855
4856         if (secmark_active)
4857                 if (avc_has_perm(peer_sid, skb->secmark,
4858                                  SECCLASS_PACKET, secmark_perm, &ad))
4859                         return NF_DROP_ERR(-ECONNREFUSED);
4860
4861         if (peerlbl_active) {
4862                 u32 if_sid;
4863                 u32 node_sid;
4864
4865                 if (sel_netif_sid(ifindex, &if_sid))
4866                         return NF_DROP;
4867                 if (avc_has_perm(peer_sid, if_sid,
4868                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
4869                         return NF_DROP_ERR(-ECONNREFUSED);
4870
4871                 if (sel_netnode_sid(addrp, family, &node_sid))
4872                         return NF_DROP;
4873                 if (avc_has_perm(peer_sid, node_sid,
4874                                  SECCLASS_NODE, NODE__SENDTO, &ad))
4875                         return NF_DROP_ERR(-ECONNREFUSED);
4876         }
4877
4878         return NF_ACCEPT;
4879 }
4880
4881 static unsigned int selinux_ipv4_postroute(unsigned int hooknum,
4882                                            struct sk_buff *skb,
4883                                            const struct net_device *in,
4884                                            const struct net_device *out,
4885                                            int (*okfn)(struct sk_buff *))
4886 {
4887         return selinux_ip_postroute(skb, out->ifindex, PF_INET);
4888 }
4889
4890 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
4891 static unsigned int selinux_ipv6_postroute(unsigned int hooknum,
4892                                            struct sk_buff *skb,
4893                                            const struct net_device *in,
4894                                            const struct net_device *out,
4895                                            int (*okfn)(struct sk_buff *))
4896 {
4897         return selinux_ip_postroute(skb, out->ifindex, PF_INET6);
4898 }
4899 #endif  /* IPV6 */
4900
4901 #endif  /* CONFIG_NETFILTER */
4902
4903 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
4904 {
4905         int err;
4906
4907         err = cap_netlink_send(sk, skb);
4908         if (err)
4909                 return err;
4910
4911         return selinux_nlmsg_perm(sk, skb);
4912 }
4913
4914 static int ipc_alloc_security(struct task_struct *task,
4915                               struct kern_ipc_perm *perm,
4916                               u16 sclass)
4917 {
4918         struct ipc_security_struct *isec;
4919         u32 sid;
4920
4921         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
4922         if (!isec)
4923                 return -ENOMEM;
4924
4925         sid = task_sid(task);
4926         isec->sclass = sclass;
4927         isec->sid = sid;
4928         perm->security = isec;
4929
4930         return 0;
4931 }
4932
4933 static void ipc_free_security(struct kern_ipc_perm *perm)
4934 {
4935         struct ipc_security_struct *isec = perm->security;
4936         perm->security = NULL;
4937         kfree(isec);
4938 }
4939
4940 static int msg_msg_alloc_security(struct msg_msg *msg)
4941 {
4942         struct msg_security_struct *msec;
4943
4944         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
4945         if (!msec)
4946                 return -ENOMEM;
4947
4948         msec->sid = SECINITSID_UNLABELED;
4949         msg->security = msec;
4950
4951         return 0;
4952 }
4953
4954 static void msg_msg_free_security(struct msg_msg *msg)
4955 {
4956         struct msg_security_struct *msec = msg->security;
4957
4958         msg->security = NULL;
4959         kfree(msec);
4960 }
4961
4962 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
4963                         u32 perms)
4964 {
4965         struct ipc_security_struct *isec;
4966         struct common_audit_data ad;
4967         u32 sid = current_sid();
4968
4969         isec = ipc_perms->security;
4970
4971         ad.type = LSM_AUDIT_DATA_IPC;
4972         ad.u.ipc_id = ipc_perms->key;
4973
4974         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
4975 }
4976
4977 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
4978 {
4979         return msg_msg_alloc_security(msg);
4980 }
4981
4982 static void selinux_msg_msg_free_security(struct msg_msg *msg)
4983 {
4984         msg_msg_free_security(msg);
4985 }
4986
4987 /* message queue security operations */
4988 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
4989 {
4990         struct ipc_security_struct *isec;
4991         struct common_audit_data ad;
4992         u32 sid = current_sid();
4993         int rc;
4994
4995         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
4996         if (rc)
4997                 return rc;
4998
4999         isec = msq->q_perm.security;
5000
5001         ad.type = LSM_AUDIT_DATA_IPC;
5002         ad.u.ipc_id = msq->q_perm.key;
5003
5004         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5005                           MSGQ__CREATE, &ad);
5006         if (rc) {
5007                 ipc_free_security(&msq->q_perm);
5008                 return rc;
5009         }
5010         return 0;
5011 }
5012
5013 static void selinux_msg_queue_free_security(struct msg_queue *msq)
5014 {
5015         ipc_free_security(&msq->q_perm);
5016 }
5017
5018 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
5019 {
5020         struct ipc_security_struct *isec;
5021         struct common_audit_data ad;
5022         u32 sid = current_sid();
5023
5024         isec = msq->q_perm.security;
5025
5026         ad.type = LSM_AUDIT_DATA_IPC;
5027         ad.u.ipc_id = msq->q_perm.key;
5028
5029         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5030                             MSGQ__ASSOCIATE, &ad);
5031 }
5032
5033 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
5034 {
5035         int err;
5036         int perms;
5037
5038         switch (cmd) {
5039         case IPC_INFO:
5040         case MSG_INFO:
5041                 /* No specific object, just general system-wide information. */
5042                 return task_has_system(current, SYSTEM__IPC_INFO);
5043         case IPC_STAT:
5044         case MSG_STAT:
5045                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5046                 break;
5047         case IPC_SET:
5048                 perms = MSGQ__SETATTR;
5049                 break;
5050         case IPC_RMID:
5051                 perms = MSGQ__DESTROY;
5052                 break;
5053         default:
5054                 return 0;
5055         }
5056
5057         err = ipc_has_perm(&msq->q_perm, perms);
5058         return err;
5059 }
5060
5061 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
5062 {
5063         struct ipc_security_struct *isec;
5064         struct msg_security_struct *msec;
5065         struct common_audit_data ad;
5066         u32 sid = current_sid();
5067         int rc;
5068
5069         isec = msq->q_perm.security;
5070         msec = msg->security;
5071
5072         /*
5073          * First time through, need to assign label to the message
5074          */
5075         if (msec->sid == SECINITSID_UNLABELED) {
5076                 /*
5077                  * Compute new sid based on current process and
5078                  * message queue this message will be stored in
5079                  */
5080                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5081                                              NULL, &msec->sid);
5082                 if (rc)
5083                         return rc;
5084         }
5085
5086         ad.type = LSM_AUDIT_DATA_IPC;
5087         ad.u.ipc_id = msq->q_perm.key;
5088
5089         /* Can this process write to the queue? */
5090         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5091                           MSGQ__WRITE, &ad);
5092         if (!rc)
5093                 /* Can this process send the message */
5094                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5095                                   MSG__SEND, &ad);
5096         if (!rc)
5097                 /* Can the message be put in the queue? */
5098                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5099                                   MSGQ__ENQUEUE, &ad);
5100
5101         return rc;
5102 }
5103
5104 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5105                                     struct task_struct *target,
5106                                     long type, int mode)
5107 {
5108         struct ipc_security_struct *isec;
5109         struct msg_security_struct *msec;
5110         struct common_audit_data ad;
5111         u32 sid = task_sid(target);
5112         int rc;
5113
5114         isec = msq->q_perm.security;
5115         msec = msg->security;
5116
5117         ad.type = LSM_AUDIT_DATA_IPC;
5118         ad.u.ipc_id = msq->q_perm.key;
5119
5120         rc = avc_has_perm(sid, isec->sid,
5121                           SECCLASS_MSGQ, MSGQ__READ, &ad);
5122         if (!rc)
5123                 rc = avc_has_perm(sid, msec->sid,
5124                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
5125         return rc;
5126 }
5127
5128 /* Shared Memory security operations */
5129 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5130 {
5131         struct ipc_security_struct *isec;
5132         struct common_audit_data ad;
5133         u32 sid = current_sid();
5134         int rc;
5135
5136         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5137         if (rc)
5138                 return rc;
5139
5140         isec = shp->shm_perm.security;
5141
5142         ad.type = LSM_AUDIT_DATA_IPC;
5143         ad.u.ipc_id = shp->shm_perm.key;
5144
5145         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5146                           SHM__CREATE, &ad);
5147         if (rc) {
5148                 ipc_free_security(&shp->shm_perm);
5149                 return rc;
5150         }
5151         return 0;
5152 }
5153
5154 static void selinux_shm_free_security(struct shmid_kernel *shp)
5155 {
5156         ipc_free_security(&shp->shm_perm);
5157 }
5158
5159 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5160 {
5161         struct ipc_security_struct *isec;
5162         struct common_audit_data ad;
5163         u32 sid = current_sid();
5164
5165         isec = shp->shm_perm.security;
5166
5167         ad.type = LSM_AUDIT_DATA_IPC;
5168         ad.u.ipc_id = shp->shm_perm.key;
5169
5170         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5171                             SHM__ASSOCIATE, &ad);
5172 }
5173
5174 /* Note, at this point, shp is locked down */
5175 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5176 {
5177         int perms;
5178         int err;
5179
5180         switch (cmd) {
5181         case IPC_INFO:
5182         case SHM_INFO:
5183                 /* No specific object, just general system-wide information. */
5184                 return task_has_system(current, SYSTEM__IPC_INFO);
5185         case IPC_STAT:
5186         case SHM_STAT:
5187                 perms = SHM__GETATTR | SHM__ASSOCIATE;
5188                 break;
5189         case IPC_SET:
5190                 perms = SHM__SETATTR;
5191                 break;
5192         case SHM_LOCK:
5193         case SHM_UNLOCK:
5194                 perms = SHM__LOCK;
5195                 break;
5196         case IPC_RMID:
5197                 perms = SHM__DESTROY;
5198                 break;
5199         default:
5200                 return 0;
5201         }
5202
5203         err = ipc_has_perm(&shp->shm_perm, perms);
5204         return err;
5205 }
5206
5207 static int selinux_shm_shmat(struct shmid_kernel *shp,
5208                              char __user *shmaddr, int shmflg)
5209 {
5210         u32 perms;
5211
5212         if (shmflg & SHM_RDONLY)
5213                 perms = SHM__READ;
5214         else
5215                 perms = SHM__READ | SHM__WRITE;
5216
5217         return ipc_has_perm(&shp->shm_perm, perms);
5218 }
5219
5220 /* Semaphore security operations */
5221 static int selinux_sem_alloc_security(struct sem_array *sma)
5222 {
5223         struct ipc_security_struct *isec;
5224         struct common_audit_data ad;
5225         u32 sid = current_sid();
5226         int rc;
5227
5228         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5229         if (rc)
5230                 return rc;
5231
5232         isec = sma->sem_perm.security;
5233
5234         ad.type = LSM_AUDIT_DATA_IPC;
5235         ad.u.ipc_id = sma->sem_perm.key;
5236
5237         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5238                           SEM__CREATE, &ad);
5239         if (rc) {
5240                 ipc_free_security(&sma->sem_perm);
5241                 return rc;
5242         }
5243         return 0;
5244 }
5245
5246 static void selinux_sem_free_security(struct sem_array *sma)
5247 {
5248         ipc_free_security(&sma->sem_perm);
5249 }
5250
5251 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5252 {
5253         struct ipc_security_struct *isec;
5254         struct common_audit_data ad;
5255         u32 sid = current_sid();
5256
5257         isec = sma->sem_perm.security;
5258
5259         ad.type = LSM_AUDIT_DATA_IPC;
5260         ad.u.ipc_id = sma->sem_perm.key;
5261
5262         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5263                             SEM__ASSOCIATE, &ad);
5264 }
5265
5266 /* Note, at this point, sma is locked down */
5267 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5268 {
5269         int err;
5270         u32 perms;
5271
5272         switch (cmd) {
5273         case IPC_INFO:
5274         case SEM_INFO:
5275                 /* No specific object, just general system-wide information. */
5276                 return task_has_system(current, SYSTEM__IPC_INFO);
5277         case GETPID:
5278         case GETNCNT:
5279         case GETZCNT:
5280                 perms = SEM__GETATTR;
5281                 break;
5282         case GETVAL:
5283         case GETALL:
5284                 perms = SEM__READ;
5285                 break;
5286         case SETVAL:
5287         case SETALL:
5288                 perms = SEM__WRITE;
5289                 break;
5290         case IPC_RMID:
5291                 perms = SEM__DESTROY;
5292                 break;
5293         case IPC_SET:
5294                 perms = SEM__SETATTR;
5295                 break;
5296         case IPC_STAT:
5297         case SEM_STAT:
5298                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5299                 break;
5300         default:
5301                 return 0;
5302         }
5303
5304         err = ipc_has_perm(&sma->sem_perm, perms);
5305         return err;
5306 }
5307
5308 static int selinux_sem_semop(struct sem_array *sma,
5309                              struct sembuf *sops, unsigned nsops, int alter)
5310 {
5311         u32 perms;
5312
5313         if (alter)
5314                 perms = SEM__READ | SEM__WRITE;
5315         else
5316                 perms = SEM__READ;
5317
5318         return ipc_has_perm(&sma->sem_perm, perms);
5319 }
5320
5321 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5322 {
5323         u32 av = 0;
5324
5325         av = 0;
5326         if (flag & S_IRUGO)
5327                 av |= IPC__UNIX_READ;
5328         if (flag & S_IWUGO)
5329                 av |= IPC__UNIX_WRITE;
5330
5331         if (av == 0)
5332                 return 0;
5333
5334         return ipc_has_perm(ipcp, av);
5335 }
5336
5337 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5338 {
5339         struct ipc_security_struct *isec = ipcp->security;
5340         *secid = isec->sid;
5341 }
5342
5343 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5344 {
5345         if (inode)
5346                 inode_doinit_with_dentry(inode, dentry);
5347 }
5348
5349 static int selinux_getprocattr(struct task_struct *p,
5350                                char *name, char **value)
5351 {
5352         const struct task_security_struct *__tsec;
5353         u32 sid;
5354         int error;
5355         unsigned len;
5356
5357         if (current != p) {
5358                 error = current_has_perm(p, PROCESS__GETATTR);
5359                 if (error)
5360                         return error;
5361         }
5362
5363         rcu_read_lock();
5364         __tsec = __task_cred(p)->security;
5365
5366         if (!strcmp(name, "current"))
5367                 sid = __tsec->sid;
5368         else if (!strcmp(name, "prev"))
5369                 sid = __tsec->osid;
5370         else if (!strcmp(name, "exec"))
5371                 sid = __tsec->exec_sid;
5372         else if (!strcmp(name, "fscreate"))
5373                 sid = __tsec->create_sid;
5374         else if (!strcmp(name, "keycreate"))
5375                 sid = __tsec->keycreate_sid;
5376         else if (!strcmp(name, "sockcreate"))
5377                 sid = __tsec->sockcreate_sid;
5378         else
5379                 goto invalid;
5380         rcu_read_unlock();
5381
5382         if (!sid)
5383                 return 0;
5384
5385         error = security_sid_to_context(sid, value, &len);
5386         if (error)
5387                 return error;
5388         return len;
5389
5390 invalid:
5391         rcu_read_unlock();
5392         return -EINVAL;
5393 }
5394
5395 static int selinux_setprocattr(struct task_struct *p,
5396                                char *name, void *value, size_t size)
5397 {
5398         struct task_security_struct *tsec;
5399         struct task_struct *tracer;
5400         struct cred *new;
5401         u32 sid = 0, ptsid;
5402         int error;
5403         char *str = value;
5404
5405         if (current != p) {
5406                 /* SELinux only allows a process to change its own
5407                    security attributes. */
5408                 return -EACCES;
5409         }
5410
5411         /*
5412          * Basic control over ability to set these attributes at all.
5413          * current == p, but we'll pass them separately in case the
5414          * above restriction is ever removed.
5415          */
5416         if (!strcmp(name, "exec"))
5417                 error = current_has_perm(p, PROCESS__SETEXEC);
5418         else if (!strcmp(name, "fscreate"))
5419                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5420         else if (!strcmp(name, "keycreate"))
5421                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5422         else if (!strcmp(name, "sockcreate"))
5423                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5424         else if (!strcmp(name, "current"))
5425                 error = current_has_perm(p, PROCESS__SETCURRENT);
5426         else
5427                 error = -EINVAL;
5428         if (error)
5429                 return error;
5430
5431         /* Obtain a SID for the context, if one was specified. */
5432         if (size && str[1] && str[1] != '\n') {
5433                 if (str[size-1] == '\n') {
5434                         str[size-1] = 0;
5435                         size--;
5436                 }
5437                 error = security_context_to_sid(value, size, &sid);
5438                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5439                         if (!capable(CAP_MAC_ADMIN)) {
5440                                 struct audit_buffer *ab;
5441                                 size_t audit_size;
5442
5443                                 /* We strip a nul only if it is at the end, otherwise the
5444                                  * context contains a nul and we should audit that */
5445                                 if (str[size - 1] == '\0')
5446                                         audit_size = size - 1;
5447                                 else
5448                                         audit_size = size;
5449                                 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5450                                 audit_log_format(ab, "op=fscreate invalid_context=");
5451                                 audit_log_n_untrustedstring(ab, value, audit_size);
5452                                 audit_log_end(ab);
5453
5454                                 return error;
5455                         }
5456                         error = security_context_to_sid_force(value, size,
5457                                                               &sid);
5458                 }
5459                 if (error)
5460                         return error;
5461         }
5462
5463         new = prepare_creds();
5464         if (!new)
5465                 return -ENOMEM;
5466
5467         /* Permission checking based on the specified context is
5468            performed during the actual operation (execve,
5469            open/mkdir/...), when we know the full context of the
5470            operation.  See selinux_bprm_set_creds for the execve
5471            checks and may_create for the file creation checks. The
5472            operation will then fail if the context is not permitted. */
5473         tsec = new->security;
5474         if (!strcmp(name, "exec")) {
5475                 tsec->exec_sid = sid;
5476         } else if (!strcmp(name, "fscreate")) {
5477                 tsec->create_sid = sid;
5478         } else if (!strcmp(name, "keycreate")) {
5479                 error = may_create_key(sid, p);
5480                 if (error)
5481                         goto abort_change;
5482                 tsec->keycreate_sid = sid;
5483         } else if (!strcmp(name, "sockcreate")) {
5484                 tsec->sockcreate_sid = sid;
5485         } else if (!strcmp(name, "current")) {
5486                 error = -EINVAL;
5487                 if (sid == 0)
5488                         goto abort_change;
5489
5490                 /* Only allow single threaded processes to change context */
5491                 error = -EPERM;
5492                 if (!current_is_single_threaded()) {
5493                         error = security_bounded_transition(tsec->sid, sid);
5494                         if (error)
5495                                 goto abort_change;
5496                 }
5497
5498                 /* Check permissions for the transition. */
5499                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5500                                      PROCESS__DYNTRANSITION, NULL);
5501                 if (error)
5502                         goto abort_change;
5503
5504                 /* Check for ptracing, and update the task SID if ok.
5505                    Otherwise, leave SID unchanged and fail. */
5506                 ptsid = 0;
5507                 task_lock(p);
5508                 tracer = ptrace_parent(p);
5509                 if (tracer)
5510                         ptsid = task_sid(tracer);
5511                 task_unlock(p);
5512
5513                 if (tracer) {
5514                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5515                                              PROCESS__PTRACE, NULL);
5516                         if (error)
5517                                 goto abort_change;
5518                 }
5519
5520                 tsec->sid = sid;
5521         } else {
5522                 error = -EINVAL;
5523                 goto abort_change;
5524         }
5525
5526         commit_creds(new);
5527         return size;
5528
5529 abort_change:
5530         abort_creds(new);
5531         return error;
5532 }
5533
5534 static int selinux_ismaclabel(const char *name)
5535 {
5536         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
5537 }
5538
5539 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5540 {
5541         return security_sid_to_context(secid, secdata, seclen);
5542 }
5543
5544 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5545 {
5546         return security_context_to_sid(secdata, seclen, secid);
5547 }
5548
5549 static void selinux_release_secctx(char *secdata, u32 seclen)
5550 {
5551         kfree(secdata);
5552 }
5553
5554 /*
5555  *      called with inode->i_mutex locked
5556  */
5557 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
5558 {
5559         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
5560 }
5561
5562 /*
5563  *      called with inode->i_mutex locked
5564  */
5565 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
5566 {
5567         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
5568 }
5569
5570 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
5571 {
5572         int len = 0;
5573         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
5574                                                 ctx, true);
5575         if (len < 0)
5576                 return len;
5577         *ctxlen = len;
5578         return 0;
5579 }
5580 #ifdef CONFIG_KEYS
5581
5582 static int selinux_key_alloc(struct key *k, const struct cred *cred,
5583                              unsigned long flags)
5584 {
5585         const struct task_security_struct *tsec;
5586         struct key_security_struct *ksec;
5587
5588         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
5589         if (!ksec)
5590                 return -ENOMEM;
5591
5592         tsec = cred->security;
5593         if (tsec->keycreate_sid)
5594                 ksec->sid = tsec->keycreate_sid;
5595         else
5596                 ksec->sid = tsec->sid;
5597
5598         k->security = ksec;
5599         return 0;
5600 }
5601
5602 static void selinux_key_free(struct key *k)
5603 {
5604         struct key_security_struct *ksec = k->security;
5605
5606         k->security = NULL;
5607         kfree(ksec);
5608 }
5609
5610 static int selinux_key_permission(key_ref_t key_ref,
5611                                   const struct cred *cred,
5612                                   key_perm_t perm)
5613 {
5614         struct key *key;
5615         struct key_security_struct *ksec;
5616         u32 sid;
5617
5618         /* if no specific permissions are requested, we skip the
5619            permission check. No serious, additional covert channels
5620            appear to be created. */
5621         if (perm == 0)
5622                 return 0;
5623
5624         sid = cred_sid(cred);
5625
5626         key = key_ref_to_ptr(key_ref);
5627         ksec = key->security;
5628
5629         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
5630 }
5631
5632 static int selinux_key_getsecurity(struct key *key, char **_buffer)
5633 {
5634         struct key_security_struct *ksec = key->security;
5635         char *context = NULL;
5636         unsigned len;
5637         int rc;
5638
5639         rc = security_sid_to_context(ksec->sid, &context, &len);
5640         if (!rc)
5641                 rc = len;
5642         *_buffer = context;
5643         return rc;
5644 }
5645
5646 #endif
5647
5648 static struct security_operations selinux_ops = {
5649         .name =                         "selinux",
5650
5651         .ptrace_access_check =          selinux_ptrace_access_check,
5652         .ptrace_traceme =               selinux_ptrace_traceme,
5653         .capget =                       selinux_capget,
5654         .capset =                       selinux_capset,
5655         .capable =                      selinux_capable,
5656         .quotactl =                     selinux_quotactl,
5657         .quota_on =                     selinux_quota_on,
5658         .syslog =                       selinux_syslog,
5659         .vm_enough_memory =             selinux_vm_enough_memory,
5660
5661         .netlink_send =                 selinux_netlink_send,
5662
5663         .bprm_set_creds =               selinux_bprm_set_creds,
5664         .bprm_committing_creds =        selinux_bprm_committing_creds,
5665         .bprm_committed_creds =         selinux_bprm_committed_creds,
5666         .bprm_secureexec =              selinux_bprm_secureexec,
5667
5668         .sb_alloc_security =            selinux_sb_alloc_security,
5669         .sb_free_security =             selinux_sb_free_security,
5670         .sb_copy_data =                 selinux_sb_copy_data,
5671         .sb_remount =                   selinux_sb_remount,
5672         .sb_kern_mount =                selinux_sb_kern_mount,
5673         .sb_show_options =              selinux_sb_show_options,
5674         .sb_statfs =                    selinux_sb_statfs,
5675         .sb_mount =                     selinux_mount,
5676         .sb_umount =                    selinux_umount,
5677         .sb_set_mnt_opts =              selinux_set_mnt_opts,
5678         .sb_clone_mnt_opts =            selinux_sb_clone_mnt_opts,
5679         .sb_parse_opts_str =            selinux_parse_opts_str,
5680
5681         .dentry_init_security =         selinux_dentry_init_security,
5682
5683         .inode_alloc_security =         selinux_inode_alloc_security,
5684         .inode_free_security =          selinux_inode_free_security,
5685         .inode_init_security =          selinux_inode_init_security,
5686         .inode_create =                 selinux_inode_create,
5687         .inode_link =                   selinux_inode_link,
5688         .inode_unlink =                 selinux_inode_unlink,
5689         .inode_symlink =                selinux_inode_symlink,
5690         .inode_mkdir =                  selinux_inode_mkdir,
5691         .inode_rmdir =                  selinux_inode_rmdir,
5692         .inode_mknod =                  selinux_inode_mknod,
5693         .inode_rename =                 selinux_inode_rename,
5694         .inode_readlink =               selinux_inode_readlink,
5695         .inode_follow_link =            selinux_inode_follow_link,
5696         .inode_permission =             selinux_inode_permission,
5697         .inode_setattr =                selinux_inode_setattr,
5698         .inode_getattr =                selinux_inode_getattr,
5699         .inode_setxattr =               selinux_inode_setxattr,
5700         .inode_post_setxattr =          selinux_inode_post_setxattr,
5701         .inode_getxattr =               selinux_inode_getxattr,
5702         .inode_listxattr =              selinux_inode_listxattr,
5703         .inode_removexattr =            selinux_inode_removexattr,
5704         .inode_getsecurity =            selinux_inode_getsecurity,
5705         .inode_setsecurity =            selinux_inode_setsecurity,
5706         .inode_listsecurity =           selinux_inode_listsecurity,
5707         .inode_getsecid =               selinux_inode_getsecid,
5708
5709         .file_permission =              selinux_file_permission,
5710         .file_alloc_security =          selinux_file_alloc_security,
5711         .file_free_security =           selinux_file_free_security,
5712         .file_ioctl =                   selinux_file_ioctl,
5713         .mmap_file =                    selinux_mmap_file,
5714         .mmap_addr =                    selinux_mmap_addr,
5715         .file_mprotect =                selinux_file_mprotect,
5716         .file_lock =                    selinux_file_lock,
5717         .file_fcntl =                   selinux_file_fcntl,
5718         .file_set_fowner =              selinux_file_set_fowner,
5719         .file_send_sigiotask =          selinux_file_send_sigiotask,
5720         .file_receive =                 selinux_file_receive,
5721
5722         .file_open =                    selinux_file_open,
5723
5724         .task_create =                  selinux_task_create,
5725         .cred_alloc_blank =             selinux_cred_alloc_blank,
5726         .cred_free =                    selinux_cred_free,
5727         .cred_prepare =                 selinux_cred_prepare,
5728         .cred_transfer =                selinux_cred_transfer,
5729         .kernel_act_as =                selinux_kernel_act_as,
5730         .kernel_create_files_as =       selinux_kernel_create_files_as,
5731         .kernel_module_request =        selinux_kernel_module_request,
5732         .task_setpgid =                 selinux_task_setpgid,
5733         .task_getpgid =                 selinux_task_getpgid,
5734         .task_getsid =                  selinux_task_getsid,
5735         .task_getsecid =                selinux_task_getsecid,
5736         .task_setnice =                 selinux_task_setnice,
5737         .task_setioprio =               selinux_task_setioprio,
5738         .task_getioprio =               selinux_task_getioprio,
5739         .task_setrlimit =               selinux_task_setrlimit,
5740         .task_setscheduler =            selinux_task_setscheduler,
5741         .task_getscheduler =            selinux_task_getscheduler,
5742         .task_movememory =              selinux_task_movememory,
5743         .task_kill =                    selinux_task_kill,
5744         .task_wait =                    selinux_task_wait,
5745         .task_to_inode =                selinux_task_to_inode,
5746
5747         .ipc_permission =               selinux_ipc_permission,
5748         .ipc_getsecid =                 selinux_ipc_getsecid,
5749
5750         .msg_msg_alloc_security =       selinux_msg_msg_alloc_security,
5751         .msg_msg_free_security =        selinux_msg_msg_free_security,
5752
5753         .msg_queue_alloc_security =     selinux_msg_queue_alloc_security,
5754         .msg_queue_free_security =      selinux_msg_queue_free_security,
5755         .msg_queue_associate =          selinux_msg_queue_associate,
5756         .msg_queue_msgctl =             selinux_msg_queue_msgctl,
5757         .msg_queue_msgsnd =             selinux_msg_queue_msgsnd,
5758         .msg_queue_msgrcv =             selinux_msg_queue_msgrcv,
5759
5760         .shm_alloc_security =           selinux_shm_alloc_security,
5761         .shm_free_security =            selinux_shm_free_security,
5762         .shm_associate =                selinux_shm_associate,
5763         .shm_shmctl =                   selinux_shm_shmctl,
5764         .shm_shmat =                    selinux_shm_shmat,
5765
5766         .sem_alloc_security =           selinux_sem_alloc_security,
5767         .sem_free_security =            selinux_sem_free_security,
5768         .sem_associate =                selinux_sem_associate,
5769         .sem_semctl =                   selinux_sem_semctl,
5770         .sem_semop =                    selinux_sem_semop,
5771
5772         .d_instantiate =                selinux_d_instantiate,
5773
5774         .getprocattr =                  selinux_getprocattr,
5775         .setprocattr =                  selinux_setprocattr,
5776
5777         .ismaclabel =                   selinux_ismaclabel,
5778         .secid_to_secctx =              selinux_secid_to_secctx,
5779         .secctx_to_secid =              selinux_secctx_to_secid,
5780         .release_secctx =               selinux_release_secctx,
5781         .inode_notifysecctx =           selinux_inode_notifysecctx,
5782         .inode_setsecctx =              selinux_inode_setsecctx,
5783         .inode_getsecctx =              selinux_inode_getsecctx,
5784
5785         .unix_stream_connect =          selinux_socket_unix_stream_connect,
5786         .unix_may_send =                selinux_socket_unix_may_send,
5787
5788         .socket_create =                selinux_socket_create,
5789         .socket_post_create =           selinux_socket_post_create,
5790         .socket_bind =                  selinux_socket_bind,
5791         .socket_connect =               selinux_socket_connect,
5792         .socket_listen =                selinux_socket_listen,
5793         .socket_accept =                selinux_socket_accept,
5794         .socket_sendmsg =               selinux_socket_sendmsg,
5795         .socket_recvmsg =               selinux_socket_recvmsg,
5796         .socket_getsockname =           selinux_socket_getsockname,
5797         .socket_getpeername =           selinux_socket_getpeername,
5798         .socket_getsockopt =            selinux_socket_getsockopt,
5799         .socket_setsockopt =            selinux_socket_setsockopt,
5800         .socket_shutdown =              selinux_socket_shutdown,
5801         .socket_sock_rcv_skb =          selinux_socket_sock_rcv_skb,
5802         .socket_getpeersec_stream =     selinux_socket_getpeersec_stream,
5803         .socket_getpeersec_dgram =      selinux_socket_getpeersec_dgram,
5804         .sk_alloc_security =            selinux_sk_alloc_security,
5805         .sk_free_security =             selinux_sk_free_security,
5806         .sk_clone_security =            selinux_sk_clone_security,
5807         .sk_getsecid =                  selinux_sk_getsecid,
5808         .sock_graft =                   selinux_sock_graft,
5809         .inet_conn_request =            selinux_inet_conn_request,
5810         .inet_csk_clone =               selinux_inet_csk_clone,
5811         .inet_conn_established =        selinux_inet_conn_established,
5812         .secmark_relabel_packet =       selinux_secmark_relabel_packet,
5813         .secmark_refcount_inc =         selinux_secmark_refcount_inc,
5814         .secmark_refcount_dec =         selinux_secmark_refcount_dec,
5815         .req_classify_flow =            selinux_req_classify_flow,
5816         .tun_dev_alloc_security =       selinux_tun_dev_alloc_security,
5817         .tun_dev_free_security =        selinux_tun_dev_free_security,
5818         .tun_dev_create =               selinux_tun_dev_create,
5819         .tun_dev_attach_queue =         selinux_tun_dev_attach_queue,
5820         .tun_dev_attach =               selinux_tun_dev_attach,
5821         .tun_dev_open =                 selinux_tun_dev_open,
5822         .skb_owned_by =                 selinux_skb_owned_by,
5823
5824 #ifdef CONFIG_SECURITY_NETWORK_XFRM
5825         .xfrm_policy_alloc_security =   selinux_xfrm_policy_alloc,
5826         .xfrm_policy_clone_security =   selinux_xfrm_policy_clone,
5827         .xfrm_policy_free_security =    selinux_xfrm_policy_free,
5828         .xfrm_policy_delete_security =  selinux_xfrm_policy_delete,
5829         .xfrm_state_alloc =             selinux_xfrm_state_alloc,
5830         .xfrm_state_alloc_acquire =     selinux_xfrm_state_alloc_acquire,
5831         .xfrm_state_free_security =     selinux_xfrm_state_free,
5832         .xfrm_state_delete_security =   selinux_xfrm_state_delete,
5833         .xfrm_policy_lookup =           selinux_xfrm_policy_lookup,
5834         .xfrm_state_pol_flow_match =    selinux_xfrm_state_pol_flow_match,
5835         .xfrm_decode_session =          selinux_xfrm_decode_session,
5836 #endif
5837
5838 #ifdef CONFIG_KEYS
5839         .key_alloc =                    selinux_key_alloc,
5840         .key_free =                     selinux_key_free,
5841         .key_permission =               selinux_key_permission,
5842         .key_getsecurity =              selinux_key_getsecurity,
5843 #endif
5844
5845 #ifdef CONFIG_AUDIT
5846         .audit_rule_init =              selinux_audit_rule_init,
5847         .audit_rule_known =             selinux_audit_rule_known,
5848         .audit_rule_match =             selinux_audit_rule_match,
5849         .audit_rule_free =              selinux_audit_rule_free,
5850 #endif
5851 };
5852
5853 static __init int selinux_init(void)
5854 {
5855         if (!security_module_enable(&selinux_ops)) {
5856                 selinux_enabled = 0;
5857                 return 0;
5858         }
5859
5860         if (!selinux_enabled) {
5861                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
5862                 return 0;
5863         }
5864
5865         printk(KERN_INFO "SELinux:  Initializing.\n");
5866
5867         /* Set the security state for the initial task. */
5868         cred_init_security();
5869
5870         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
5871
5872         sel_inode_cache = kmem_cache_create("selinux_inode_security",
5873                                             sizeof(struct inode_security_struct),
5874                                             0, SLAB_PANIC, NULL);
5875         avc_init();
5876
5877         if (register_security(&selinux_ops))
5878                 panic("SELinux: Unable to register with kernel.\n");
5879
5880         if (selinux_enforcing)
5881                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
5882         else
5883                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
5884
5885         return 0;
5886 }
5887
5888 static void delayed_superblock_init(struct super_block *sb, void *unused)
5889 {
5890         superblock_doinit(sb, NULL);
5891 }
5892
5893 void selinux_complete_init(void)
5894 {
5895         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
5896
5897         /* Set up any superblocks initialized prior to the policy load. */
5898         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
5899         iterate_supers(delayed_superblock_init, NULL);
5900 }
5901
5902 /* SELinux requires early initialization in order to label
5903    all processes and objects when they are created. */
5904 security_initcall(selinux_init);
5905
5906 #if defined(CONFIG_NETFILTER)
5907
5908 static struct nf_hook_ops selinux_ipv4_ops[] = {
5909         {
5910                 .hook =         selinux_ipv4_postroute,
5911                 .owner =        THIS_MODULE,
5912                 .pf =           NFPROTO_IPV4,
5913                 .hooknum =      NF_INET_POST_ROUTING,
5914                 .priority =     NF_IP_PRI_SELINUX_LAST,
5915         },
5916         {
5917                 .hook =         selinux_ipv4_forward,
5918                 .owner =        THIS_MODULE,
5919                 .pf =           NFPROTO_IPV4,
5920                 .hooknum =      NF_INET_FORWARD,
5921                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5922         },
5923         {
5924                 .hook =         selinux_ipv4_output,
5925                 .owner =        THIS_MODULE,
5926                 .pf =           NFPROTO_IPV4,
5927                 .hooknum =      NF_INET_LOCAL_OUT,
5928                 .priority =     NF_IP_PRI_SELINUX_FIRST,
5929         }
5930 };
5931
5932 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5933
5934 static struct nf_hook_ops selinux_ipv6_ops[] = {
5935         {
5936                 .hook =         selinux_ipv6_postroute,
5937                 .owner =        THIS_MODULE,
5938                 .pf =           NFPROTO_IPV6,
5939                 .hooknum =      NF_INET_POST_ROUTING,
5940                 .priority =     NF_IP6_PRI_SELINUX_LAST,
5941         },
5942         {
5943                 .hook =         selinux_ipv6_forward,
5944                 .owner =        THIS_MODULE,
5945                 .pf =           NFPROTO_IPV6,
5946                 .hooknum =      NF_INET_FORWARD,
5947                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
5948         }
5949 };
5950
5951 #endif  /* IPV6 */
5952
5953 static int __init selinux_nf_ip_init(void)
5954 {
5955         int err = 0;
5956
5957         if (!selinux_enabled)
5958                 goto out;
5959
5960         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
5961
5962         err = nf_register_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5963         if (err)
5964                 panic("SELinux: nf_register_hooks for IPv4: error %d\n", err);
5965
5966 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5967         err = nf_register_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5968         if (err)
5969                 panic("SELinux: nf_register_hooks for IPv6: error %d\n", err);
5970 #endif  /* IPV6 */
5971
5972 out:
5973         return err;
5974 }
5975
5976 __initcall(selinux_nf_ip_init);
5977
5978 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5979 static void selinux_nf_ip_exit(void)
5980 {
5981         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
5982
5983         nf_unregister_hooks(selinux_ipv4_ops, ARRAY_SIZE(selinux_ipv4_ops));
5984 #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
5985         nf_unregister_hooks(selinux_ipv6_ops, ARRAY_SIZE(selinux_ipv6_ops));
5986 #endif  /* IPV6 */
5987 }
5988 #endif
5989
5990 #else /* CONFIG_NETFILTER */
5991
5992 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5993 #define selinux_nf_ip_exit()
5994 #endif
5995
5996 #endif /* CONFIG_NETFILTER */
5997
5998 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
5999 static int selinux_disabled;
6000
6001 int selinux_disable(void)
6002 {
6003         if (ss_initialized) {
6004                 /* Not permitted after initial policy load. */
6005                 return -EINVAL;
6006         }
6007
6008         if (selinux_disabled) {
6009                 /* Only do this once. */
6010                 return -EINVAL;
6011         }
6012
6013         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
6014
6015         selinux_disabled = 1;
6016         selinux_enabled = 0;
6017
6018         reset_security_ops();
6019
6020         /* Try to destroy the avc node cache */
6021         avc_disable();
6022
6023         /* Unregister netfilter hooks. */
6024         selinux_nf_ip_exit();
6025
6026         /* Unregister selinuxfs. */
6027         exit_sel_fs();
6028
6029         return 0;
6030 }
6031 #endif