Pileus Git - ~andy/linux/blob - security/selinux/hooks.c

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