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, <[email protected]>
   7  *            Chris Vance, <[email protected]>
   8  *            Wayne Salamon, <[email protected]>
   9  *            James Morris <[email protected]>
  10  *
  11  *  Copyright (C) 2001,2002 Networks Associates Technology, Inc.
  12  *  Copyright (C) 2003-2008 Red Hat, Inc., James Morris <[email protected]>
  13  *                                         Eric Paris <[email protected]>
  14  *  Copyright (C) 2004-2005 Trusted Computer Solutions, Inc.
  15  *                          <[email protected]>
  16  *  Copyright (C) 2006, 2007, 2009 Hewlett-Packard Development Company, L.P.
  17  *      Paul Moore <[email protected]>
  18  *  Copyright (C) 2007 Hitachi Software Engineering Co., Ltd.
  19  *                     Yuichi Nakamura <[email protected]>
  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/lsm_hooks.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/inet_connection_sock.h>
  56 #include <net/net_namespace.h>
  57 #include <net/netlabel.h>
  58 #include <linux/uaccess.h>
  59 #include <asm/ioctls.h>
  60 #include <linux/atomic.h>
  61 #include <linux/bitops.h>
  62 #include <linux/interrupt.h>
  63 #include <linux/netdevice.h>    /* for network interface checks */
  64 #include <net/netlink.h>
  65 #include <linux/tcp.h>
  66 #include <linux/udp.h>
  67 #include <linux/dccp.h>
  68 #include <linux/quota.h>
  69 #include <linux/un.h>           /* for Unix socket types */
  70 #include <net/af_unix.h>        /* for Unix socket types */
  71 #include <linux/parser.h>
  72 #include <linux/nfs_mount.h>
  73 #include <net/ipv6.h>
  74 #include <linux/hugetlb.h>
  75 #include <linux/personality.h>
  76 #include <linux/audit.h>
  77 #include <linux/string.h>
  78 #include <linux/selinux.h>
  79 #include <linux/mutex.h>
  80 #include <linux/posix-timers.h>
  81 #include <linux/syslog.h>
  82 #include <linux/user_namespace.h>
  83 #include <linux/export.h>
  84 #include <linux/msg.h>
  85 #include <linux/shm.h>
  86
  87 #include "avc.h"
  88 #include "objsec.h"
  89 #include "netif.h"
  90 #include "netnode.h"
  91 #include "netport.h"
  92 #include "xfrm.h"
  93 #include "netlabel.h"
  94 #include "audit.h"
  95 #include "avc_ss.h"
  96
  97 /* SECMARK reference count */
  98 static atomic_t selinux_secmark_refcount = ATOMIC_INIT(0);
  99
 100 #ifdef CONFIG_SECURITY_SELINUX_DEVELOP
 101 int selinux_enforcing;
 102
 103 static int __init enforcing_setup(char *str)
 104 {
 105         unsigned long enforcing;
 106         if (!kstrtoul(str, 0, &enforcing))
 107                 selinux_enforcing = enforcing ? 1 : 0;
 108         return 1;
 109 }
 110 __setup("enforcing=", enforcing_setup);
 111 #endif
 112
 113 #ifdef CONFIG_SECURITY_SELINUX_BOOTPARAM
 114 int selinux_enabled = CONFIG_SECURITY_SELINUX_BOOTPARAM_VALUE;
 115
 116 static int __init selinux_enabled_setup(char *str)
 117 {
 118         unsigned long enabled;
 119         if (!kstrtoul(str, 0, &enabled))
 120                 selinux_enabled = enabled ? 1 : 0;
 121         return 1;
 122 }
 123 __setup("selinux=", selinux_enabled_setup);
 124 #else
 125 int selinux_enabled = 1;
 126 #endif
 127
 128 static struct kmem_cache *sel_inode_cache;
 129 static struct kmem_cache *file_security_cache;
 130
 131 /**
 132  * selinux_secmark_enabled - Check to see if SECMARK is currently enabled
 133  *
 134  * Description:
 135  * This function checks the SECMARK reference counter to see if any SECMARK
 136  * targets are currently configured, if the reference counter is greater than
 137  * zero SECMARK is considered to be enabled.  Returns true (1) if SECMARK is
 138  * enabled, false (0) if SECMARK is disabled.  If the always_check_network
 139  * policy capability is enabled, SECMARK is always considered enabled.
 140  *
 141  */
 142 static int selinux_secmark_enabled(void)
 143 {
 144         return (selinux_policycap_alwaysnetwork || atomic_read(&selinux_secmark_refcount));
 145 }
 146
 147 /**
 148  * selinux_peerlbl_enabled - Check to see if peer labeling is currently enabled
 149  *
 150  * Description:
 151  * This function checks if NetLabel or labeled IPSEC is enabled.  Returns true
 152  * (1) if any are enabled or false (0) if neither are enabled.  If the
 153  * always_check_network policy capability is enabled, peer labeling
 154  * is always considered enabled.
 155  *
 156  */
 157 static int selinux_peerlbl_enabled(void)
 158 {
 159         return (selinux_policycap_alwaysnetwork || netlbl_enabled() || selinux_xfrm_enabled());
 160 }
 161
 162 static int selinux_netcache_avc_callback(u32 event)
 163 {
 164         if (event == AVC_CALLBACK_RESET) {
 165                 sel_netif_flush();
 166                 sel_netnode_flush();
 167                 sel_netport_flush();
 168                 synchronize_net();
 169         }
 170         return 0;
 171 }
 172
 173 /*
 174  * initialise the security for the init task
 175  */
 176 static void cred_init_security(void)
 177 {
 178         struct cred *cred = (struct cred *) current->real_cred;
 179         struct task_security_struct *tsec;
 180
 181         tsec = kzalloc(sizeof(struct task_security_struct), GFP_KERNEL);
 182         if (!tsec)
 183                 panic("SELinux:  Failed to initialize initial task.\n");
 184
 185         tsec->osid = tsec->sid = SECINITSID_KERNEL;
 186         cred->security = tsec;
 187 }
 188
 189 /*
 190  * get the security ID of a set of credentials
 191  */
 192 static inline u32 cred_sid(const struct cred *cred)
 193 {
 194         const struct task_security_struct *tsec;
 195
 196         tsec = cred->security;
 197         return tsec->sid;
 198 }
 199
 200 /*
 201  * get the objective security ID of a task
 202  */
 203 static inline u32 task_sid(const struct task_struct *task)
 204 {
 205         u32 sid;
 206
 207         rcu_read_lock();
 208         sid = cred_sid(__task_cred(task));
 209         rcu_read_unlock();
 210         return sid;
 211 }
 212
 213 /*
 214  * get the subjective security ID of the current task
 215  */
 216 static inline u32 current_sid(void)
 217 {
 218         const struct task_security_struct *tsec = current_security();
 219
 220         return tsec->sid;
 221 }
 222
 223 /* Allocate and free functions for each kind of security blob. */
 224
 225 static int inode_alloc_security(struct inode *inode)
 226 {
 227         struct inode_security_struct *isec;
 228         u32 sid = current_sid();
 229
 230         isec = kmem_cache_zalloc(sel_inode_cache, GFP_NOFS);
 231         if (!isec)
 232                 return -ENOMEM;
 233
 234         spin_lock_init(&isec->lock);
 235         INIT_LIST_HEAD(&isec->list);
 236         isec->inode = inode;
 237         isec->sid = SECINITSID_UNLABELED;
 238         isec->sclass = SECCLASS_FILE;
 239         isec->task_sid = sid;
 240         isec->initialized = LABEL_INVALID;
 241         inode->i_security = isec;
 242
 243         return 0;
 244 }
 245
 246 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry);
 247
 248 /*
 249  * Try reloading inode security labels that have been marked as invalid.  The
 250  * @may_sleep parameter indicates when sleeping and thus reloading labels is
 251  * allowed; when set to false, returns -ECHILD when the label is
 252  * invalid.  The @opt_dentry parameter should be set to a dentry of the inode;
 253  * when no dentry is available, set it to NULL instead.
 254  */
 255 static int __inode_security_revalidate(struct inode *inode,
 256                                        struct dentry *opt_dentry,
 257                                        bool may_sleep)
 258 {
 259         struct inode_security_struct *isec = inode->i_security;
 260
 261         might_sleep_if(may_sleep);
 262
 263         if (ss_initialized && isec->initialized != LABEL_INITIALIZED) {
 264                 if (!may_sleep)
 265                         return -ECHILD;
 266
 267                 /*
 268                  * Try reloading the inode security label.  This will fail if
 269                  * @opt_dentry is NULL and no dentry for this inode can be
 270                  * found; in that case, continue using the old label.
 271                  */
 272                 inode_doinit_with_dentry(inode, opt_dentry);
 273         }
 274         return 0;
 275 }
 276
 277 static struct inode_security_struct *inode_security_novalidate(struct inode *inode)
 278 {
 279         return inode->i_security;
 280 }
 281
 282 static struct inode_security_struct *inode_security_rcu(struct inode *inode, bool rcu)
 283 {
 284         int error;
 285
 286         error = __inode_security_revalidate(inode, NULL, !rcu);
 287         if (error)
 288                 return ERR_PTR(error);
 289         return inode->i_security;
 290 }
 291
 292 /*
 293  * Get the security label of an inode.
 294  */
 295 static struct inode_security_struct *inode_security(struct inode *inode)
 296 {
 297         __inode_security_revalidate(inode, NULL, true);
 298         return inode->i_security;
 299 }
 300
 301 static struct inode_security_struct *backing_inode_security_novalidate(struct dentry *dentry)
 302 {
 303         struct inode *inode = d_backing_inode(dentry);
 304
 305         return inode->i_security;
 306 }
 307
 308 /*
 309  * Get the security label of a dentry's backing inode.
 310  */
 311 static struct inode_security_struct *backing_inode_security(struct dentry *dentry)
 312 {
 313         struct inode *inode = d_backing_inode(dentry);
 314
 315         __inode_security_revalidate(inode, dentry, true);
 316         return inode->i_security;
 317 }
 318
 319 static void inode_free_rcu(struct rcu_head *head)
 320 {
 321         struct inode_security_struct *isec;
 322
 323         isec = container_of(head, struct inode_security_struct, rcu);
 324         kmem_cache_free(sel_inode_cache, isec);
 325 }
 326
 327 static void inode_free_security(struct inode *inode)
 328 {
 329         struct inode_security_struct *isec = inode->i_security;
 330         struct superblock_security_struct *sbsec = inode->i_sb->s_security;
 331
 332         /*
 333          * As not all inode security structures are in a list, we check for
 334          * empty list outside of the lock to make sure that we won't waste
 335          * time taking a lock doing nothing.
 336          *
 337          * The list_del_init() function can be safely called more than once.
 338          * It should not be possible for this function to be called with
 339          * concurrent list_add(), but for better safety against future changes
 340          * in the code, we use list_empty_careful() here.
 341          */
 342         if (!list_empty_careful(&isec->list)) {
 343                 spin_lock(&sbsec->isec_lock);
 344                 list_del_init(&isec->list);
 345                 spin_unlock(&sbsec->isec_lock);
 346         }
 347
 348         /*
 349          * The inode may still be referenced in a path walk and
 350          * a call to selinux_inode_permission() can be made
 351          * after inode_free_security() is called. Ideally, the VFS
 352          * wouldn't do this, but fixing that is a much harder
 353          * job. For now, simply free the i_security via RCU, and
 354          * leave the current inode->i_security pointer intact.
 355          * The inode will be freed after the RCU grace period too.
 356          */
 357         call_rcu(&isec->rcu, inode_free_rcu);
 358 }
 359
 360 static int file_alloc_security(struct file *file)
 361 {
 362         struct file_security_struct *fsec;
 363         u32 sid = current_sid();
 364
 365         fsec = kmem_cache_zalloc(file_security_cache, GFP_KERNEL);
 366         if (!fsec)
 367                 return -ENOMEM;
 368
 369         fsec->sid = sid;
 370         fsec->fown_sid = sid;
 371         file->f_security = fsec;
 372
 373         return 0;
 374 }
 375
 376 static void file_free_security(struct file *file)
 377 {
 378         struct file_security_struct *fsec = file->f_security;
 379         file->f_security = NULL;
 380         kmem_cache_free(file_security_cache, fsec);
 381 }
 382
 383 static int superblock_alloc_security(struct super_block *sb)
 384 {
 385         struct superblock_security_struct *sbsec;
 386
 387         sbsec = kzalloc(sizeof(struct superblock_security_struct), GFP_KERNEL);
 388         if (!sbsec)
 389                 return -ENOMEM;
 390
 391         mutex_init(&sbsec->lock);
 392         INIT_LIST_HEAD(&sbsec->isec_head);
 393         spin_lock_init(&sbsec->isec_lock);
 394         sbsec->sb = sb;
 395         sbsec->sid = SECINITSID_UNLABELED;
 396         sbsec->def_sid = SECINITSID_FILE;
 397         sbsec->mntpoint_sid = SECINITSID_UNLABELED;
 398         sb->s_security = sbsec;
 399
 400         return 0;
 401 }
 402
 403 static void superblock_free_security(struct super_block *sb)
 404 {
 405         struct superblock_security_struct *sbsec = sb->s_security;
 406         sb->s_security = NULL;
 407         kfree(sbsec);
 408 }
 409
 410 /* The file system's label must be initialized prior to use. */
 411
 412 static const char *labeling_behaviors[7] = {
 413         "uses xattr",
 414         "uses transition SIDs",
 415         "uses task SIDs",
 416         "uses genfs_contexts",
 417         "not configured for labeling",
 418         "uses mountpoint labeling",
 419         "uses native labeling",
 420 };
 421
 422 static inline int inode_doinit(struct inode *inode)
 423 {
 424         return inode_doinit_with_dentry(inode, NULL);
 425 }
 426
 427 enum {
 428         Opt_error = -1,
 429         Opt_context = 1,
 430         Opt_fscontext = 2,
 431         Opt_defcontext = 3,
 432         Opt_rootcontext = 4,
 433         Opt_labelsupport = 5,
 434         Opt_nextmntopt = 6,
 435 };
 436
 437 #define NUM_SEL_MNT_OPTS        (Opt_nextmntopt - 1)
 438
 439 static const match_table_t tokens = {
 440         {Opt_context, CONTEXT_STR "%s"},
 441         {Opt_fscontext, FSCONTEXT_STR "%s"},
 442         {Opt_defcontext, DEFCONTEXT_STR "%s"},
 443         {Opt_rootcontext, ROOTCONTEXT_STR "%s"},
 444         {Opt_labelsupport, LABELSUPP_STR},
 445         {Opt_error, NULL},
 446 };
 447
 448 #define SEL_MOUNT_FAIL_MSG "SELinux:  duplicate or incompatible mount options\n"
 449
 450 static int may_context_mount_sb_relabel(u32 sid,
 451                         struct superblock_security_struct *sbsec,
 452                         const struct cred *cred)
 453 {
 454         const struct task_security_struct *tsec = cred->security;
 455         int rc;
 456
 457         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 458                           FILESYSTEM__RELABELFROM, NULL);
 459         if (rc)
 460                 return rc;
 461
 462         rc = avc_has_perm(tsec->sid, sid, SECCLASS_FILESYSTEM,
 463                           FILESYSTEM__RELABELTO, NULL);
 464         return rc;
 465 }
 466
 467 static int may_context_mount_inode_relabel(u32 sid,
 468                         struct superblock_security_struct *sbsec,
 469                         const struct cred *cred)
 470 {
 471         const struct task_security_struct *tsec = cred->security;
 472         int rc;
 473         rc = avc_has_perm(tsec->sid, sbsec->sid, SECCLASS_FILESYSTEM,
 474                           FILESYSTEM__RELABELFROM, NULL);
 475         if (rc)
 476                 return rc;
 477
 478         rc = avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM,
 479                           FILESYSTEM__ASSOCIATE, NULL);
 480         return rc;
 481 }
 482
 483 static int selinux_is_sblabel_mnt(struct super_block *sb)
 484 {
 485         struct superblock_security_struct *sbsec = sb->s_security;
 486
 487         return sbsec->behavior == SECURITY_FS_USE_XATTR ||
 488                 sbsec->behavior == SECURITY_FS_USE_TRANS ||
 489                 sbsec->behavior == SECURITY_FS_USE_TASK ||
 490                 sbsec->behavior == SECURITY_FS_USE_NATIVE ||
 491                 /* Special handling. Genfs but also in-core setxattr handler */
 492                 !strcmp(sb->s_type->name, "sysfs") ||
 493                 !strcmp(sb->s_type->name, "pstore") ||
 494                 !strcmp(sb->s_type->name, "debugfs") ||
 495                 !strcmp(sb->s_type->name, "rootfs");
 496 }
 497
 498 static int sb_finish_set_opts(struct super_block *sb)
 499 {
 500         struct superblock_security_struct *sbsec = sb->s_security;
 501         struct dentry *root = sb->s_root;
 502         struct inode *root_inode = d_backing_inode(root);
 503         int rc = 0;
 504
 505         if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 506                 /* Make sure that the xattr handler exists and that no
 507                    error other than -ENODATA is returned by getxattr on
 508                    the root directory.  -ENODATA is ok, as this may be
 509                    the first boot of the SELinux kernel before we have
 510                    assigned xattr values to the filesystem. */
 511                 if (!(root_inode->i_opflags & IOP_XATTR)) {
 512                         printk(KERN_WARNING "SELinux: (dev %s, type %s) has no "
 513                                "xattr support\n", sb->s_id, sb->s_type->name);
 514                         rc = -EOPNOTSUPP;
 515                         goto out;
 516                 }
 517
 518                 rc = __vfs_getxattr(root, root_inode, XATTR_NAME_SELINUX, NULL, 0);
 519                 if (rc < 0 && rc != -ENODATA) {
 520                         if (rc == -EOPNOTSUPP)
 521                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 522                                        "%s) has no security xattr handler\n",
 523                                        sb->s_id, sb->s_type->name);
 524                         else
 525                                 printk(KERN_WARNING "SELinux: (dev %s, type "
 526                                        "%s) getxattr errno %d\n", sb->s_id,
 527                                        sb->s_type->name, -rc);
 528                         goto out;
 529                 }
 530         }
 531
 532         if (sbsec->behavior > ARRAY_SIZE(labeling_behaviors))
 533                 printk(KERN_ERR "SELinux: initialized (dev %s, type %s), unknown behavior\n",
 534                        sb->s_id, sb->s_type->name);
 535
 536         sbsec->flags |= SE_SBINITIALIZED;
 537         if (selinux_is_sblabel_mnt(sb))
 538                 sbsec->flags |= SBLABEL_MNT;
 539
 540         /* Initialize the root inode. */
 541         rc = inode_doinit_with_dentry(root_inode, root);
 542
 543         /* Initialize any other inodes associated with the superblock, e.g.
 544            inodes created prior to initial policy load or inodes created
 545            during get_sb by a pseudo filesystem that directly
 546            populates itself. */
 547         spin_lock(&sbsec->isec_lock);
 548 next_inode:
 549         if (!list_empty(&sbsec->isec_head)) {
 550                 struct inode_security_struct *isec =
 551                                 list_entry(sbsec->isec_head.next,
 552                                            struct inode_security_struct, list);
 553                 struct inode *inode = isec->inode;
 554                 list_del_init(&isec->list);
 555                 spin_unlock(&sbsec->isec_lock);
 556                 inode = igrab(inode);
 557                 if (inode) {
 558                         if (!IS_PRIVATE(inode))
 559                                 inode_doinit(inode);
 560                         iput(inode);
 561                 }
 562                 spin_lock(&sbsec->isec_lock);
 563                 goto next_inode;
 564         }
 565         spin_unlock(&sbsec->isec_lock);
 566 out:
 567         return rc;
 568 }
 569
 570 /*
 571  * This function should allow an FS to ask what it's mount security
 572  * options were so it can use those later for submounts, displaying
 573  * mount options, or whatever.
 574  */
 575 static int selinux_get_mnt_opts(const struct super_block *sb,
 576                                 struct security_mnt_opts *opts)
 577 {
 578         int rc = 0, i;
 579         struct superblock_security_struct *sbsec = sb->s_security;
 580         char *context = NULL;
 581         u32 len;
 582         char tmp;
 583
 584         security_init_mnt_opts(opts);
 585
 586         if (!(sbsec->flags & SE_SBINITIALIZED))
 587                 return -EINVAL;
 588
 589         if (!ss_initialized)
 590                 return -EINVAL;
 591
 592         /* make sure we always check enough bits to cover the mask */
 593         BUILD_BUG_ON(SE_MNTMASK >= (1 << NUM_SEL_MNT_OPTS));
 594
 595         tmp = sbsec->flags & SE_MNTMASK;
 596         /* count the number of mount options for this sb */
 597         for (i = 0; i < NUM_SEL_MNT_OPTS; i++) {
 598                 if (tmp & 0x01)
 599                         opts->num_mnt_opts++;
 600                 tmp >>= 1;
 601         }
 602         /* Check if the Label support flag is set */
 603         if (sbsec->flags & SBLABEL_MNT)
 604                 opts->num_mnt_opts++;
 605
 606         opts->mnt_opts = kcalloc(opts->num_mnt_opts, sizeof(char *), GFP_ATOMIC);
 607         if (!opts->mnt_opts) {
 608                 rc = -ENOMEM;
 609                 goto out_free;
 610         }
 611
 612         opts->mnt_opts_flags = kcalloc(opts->num_mnt_opts, sizeof(int), GFP_ATOMIC);
 613         if (!opts->mnt_opts_flags) {
 614                 rc = -ENOMEM;
 615                 goto out_free;
 616         }
 617
 618         i = 0;
 619         if (sbsec->flags & FSCONTEXT_MNT) {
 620                 rc = security_sid_to_context(sbsec->sid, &context, &len);
 621                 if (rc)
 622                         goto out_free;
 623                 opts->mnt_opts[i] = context;
 624                 opts->mnt_opts_flags[i++] = FSCONTEXT_MNT;
 625         }
 626         if (sbsec->flags & CONTEXT_MNT) {
 627                 rc = security_sid_to_context(sbsec->mntpoint_sid, &context, &len);
 628                 if (rc)
 629                         goto out_free;
 630                 opts->mnt_opts[i] = context;
 631                 opts->mnt_opts_flags[i++] = CONTEXT_MNT;
 632         }
 633         if (sbsec->flags & DEFCONTEXT_MNT) {
 634                 rc = security_sid_to_context(sbsec->def_sid, &context, &len);
 635                 if (rc)
 636                         goto out_free;
 637                 opts->mnt_opts[i] = context;
 638                 opts->mnt_opts_flags[i++] = DEFCONTEXT_MNT;
 639         }
 640         if (sbsec->flags & ROOTCONTEXT_MNT) {
 641                 struct dentry *root = sbsec->sb->s_root;
 642                 struct inode_security_struct *isec = backing_inode_security(root);
 643
 644                 rc = security_sid_to_context(isec->sid, &context, &len);
 645                 if (rc)
 646                         goto out_free;
 647                 opts->mnt_opts[i] = context;
 648                 opts->mnt_opts_flags[i++] = ROOTCONTEXT_MNT;
 649         }
 650         if (sbsec->flags & SBLABEL_MNT) {
 651                 opts->mnt_opts[i] = NULL;
 652                 opts->mnt_opts_flags[i++] = SBLABEL_MNT;
 653         }
 654
 655         BUG_ON(i != opts->num_mnt_opts);
 656
 657         return 0;
 658
 659 out_free:
 660         security_free_mnt_opts(opts);
 661         return rc;
 662 }
 663
 664 static int bad_option(struct superblock_security_struct *sbsec, char flag,
 665                       u32 old_sid, u32 new_sid)
 666 {
 667         char mnt_flags = sbsec->flags & SE_MNTMASK;
 668
 669         /* check if the old mount command had the same options */
 670         if (sbsec->flags & SE_SBINITIALIZED)
 671                 if (!(sbsec->flags & flag) ||
 672                     (old_sid != new_sid))
 673                         return 1;
 674
 675         /* check if we were passed the same options twice,
 676          * aka someone passed context=a,context=b
 677          */
 678         if (!(sbsec->flags & SE_SBINITIALIZED))
 679                 if (mnt_flags & flag)
 680                         return 1;
 681         return 0;
 682 }
 683
 684 /*
 685  * Allow filesystems with binary mount data to explicitly set mount point
 686  * labeling information.
 687  */
 688 static int selinux_set_mnt_opts(struct super_block *sb,
 689                                 struct security_mnt_opts *opts,
 690                                 unsigned long kern_flags,
 691                                 unsigned long *set_kern_flags)
 692 {
 693         const struct cred *cred = current_cred();
 694         int rc = 0, i;
 695         struct superblock_security_struct *sbsec = sb->s_security;
 696         const char *name = sb->s_type->name;
 697         struct dentry *root = sbsec->sb->s_root;
 698         struct inode_security_struct *root_isec;
 699         u32 fscontext_sid = 0, context_sid = 0, rootcontext_sid = 0;
 700         u32 defcontext_sid = 0;
 701         char **mount_options = opts->mnt_opts;
 702         int *flags = opts->mnt_opts_flags;
 703         int num_opts = opts->num_mnt_opts;
 704
 705         mutex_lock(&sbsec->lock);
 706
 707         if (!ss_initialized) {
 708                 if (!num_opts) {
 709                         /* Defer initialization until selinux_complete_init,
 710                            after the initial policy is loaded and the security
 711                            server is ready to handle calls. */
 712                         goto out;
 713                 }
 714                 rc = -EINVAL;
 715                 printk(KERN_WARNING "SELinux: Unable to set superblock options "
 716                         "before the security server is initialized\n");
 717                 goto out;
 718         }
 719         if (kern_flags && !set_kern_flags) {
 720                 /* Specifying internal flags without providing a place to
 721                  * place the results is not allowed */
 722                 rc = -EINVAL;
 723                 goto out;
 724         }
 725
 726         /*
 727          * Binary mount data FS will come through this function twice.  Once
 728          * from an explicit call and once from the generic calls from the vfs.
 729          * Since the generic VFS calls will not contain any security mount data
 730          * we need to skip the double mount verification.
 731          *
 732          * This does open a hole in which we will not notice if the first
 733          * mount using this sb set explict options and a second mount using
 734          * this sb does not set any security options.  (The first options
 735          * will be used for both mounts)
 736          */
 737         if ((sbsec->flags & SE_SBINITIALIZED) && (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
 738             && (num_opts == 0))
 739                 goto out;
 740
 741         root_isec = backing_inode_security_novalidate(root);
 742
 743         /*
 744          * parse the mount options, check if they are valid sids.
 745          * also check if someone is trying to mount the same sb more
 746          * than once with different security options.
 747          */
 748         for (i = 0; i < num_opts; i++) {
 749                 u32 sid;
 750
 751                 if (flags[i] == SBLABEL_MNT)
 752                         continue;
 753                 rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
 754                 if (rc) {
 755                         printk(KERN_WARNING "SELinux: security_context_str_to_sid"
 756                                "(%s) failed for (dev %s, type %s) errno=%d\n",
 757                                mount_options[i], sb->s_id, name, rc);
 758                         goto out;
 759                 }
 760                 switch (flags[i]) {
 761                 case FSCONTEXT_MNT:
 762                         fscontext_sid = sid;
 763
 764                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid,
 765                                         fscontext_sid))
 766                                 goto out_double_mount;
 767
 768                         sbsec->flags |= FSCONTEXT_MNT;
 769                         break;
 770                 case CONTEXT_MNT:
 771                         context_sid = sid;
 772
 773                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid,
 774                                         context_sid))
 775                                 goto out_double_mount;
 776
 777                         sbsec->flags |= CONTEXT_MNT;
 778                         break;
 779                 case ROOTCONTEXT_MNT:
 780                         rootcontext_sid = sid;
 781
 782                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid,
 783                                         rootcontext_sid))
 784                                 goto out_double_mount;
 785
 786                         sbsec->flags |= ROOTCONTEXT_MNT;
 787
 788                         break;
 789                 case DEFCONTEXT_MNT:
 790                         defcontext_sid = sid;
 791
 792                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid,
 793                                         defcontext_sid))
 794                                 goto out_double_mount;
 795
 796                         sbsec->flags |= DEFCONTEXT_MNT;
 797
 798                         break;
 799                 default:
 800                         rc = -EINVAL;
 801                         goto out;
 802                 }
 803         }
 804
 805         if (sbsec->flags & SE_SBINITIALIZED) {
 806                 /* previously mounted with options, but not on this attempt? */
 807                 if ((sbsec->flags & SE_MNTMASK) && !num_opts)
 808                         goto out_double_mount;
 809                 rc = 0;
 810                 goto out;
 811         }
 812
 813         if (strcmp(sb->s_type->name, "proc") == 0)
 814                 sbsec->flags |= SE_SBPROC | SE_SBGENFS;
 815
 816         if (!strcmp(sb->s_type->name, "debugfs") ||
 817             !strcmp(sb->s_type->name, "sysfs") ||
 818             !strcmp(sb->s_type->name, "pstore"))
 819                 sbsec->flags |= SE_SBGENFS;
 820
 821         if (!sbsec->behavior) {
 822                 /*
 823                  * Determine the labeling behavior to use for this
 824                  * filesystem type.
 825                  */
 826                 rc = security_fs_use(sb);
 827                 if (rc) {
 828                         printk(KERN_WARNING
 829                                 "%s: security_fs_use(%s) returned %d\n",
 830                                         __func__, sb->s_type->name, rc);
 831                         goto out;
 832                 }
 833         }
 834
 835         /*
 836          * If this is a user namespace mount, no contexts are allowed
 837          * on the command line and security labels must be ignored.
 838          */
 839         if (sb->s_user_ns != &init_user_ns) {
 840                 if (context_sid || fscontext_sid || rootcontext_sid ||
 841                     defcontext_sid) {
 842                         rc = -EACCES;
 843                         goto out;
 844                 }
 845                 if (sbsec->behavior == SECURITY_FS_USE_XATTR) {
 846                         sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 847                         rc = security_transition_sid(current_sid(), current_sid(),
 848                                                      SECCLASS_FILE, NULL,
 849                                                      &sbsec->mntpoint_sid);
 850                         if (rc)
 851                                 goto out;
 852                 }
 853                 goto out_set_opts;
 854         }
 855
 856         /* sets the context of the superblock for the fs being mounted. */
 857         if (fscontext_sid) {
 858                 rc = may_context_mount_sb_relabel(fscontext_sid, sbsec, cred);
 859                 if (rc)
 860                         goto out;
 861
 862                 sbsec->sid = fscontext_sid;
 863         }
 864
 865         /*
 866          * Switch to using mount point labeling behavior.
 867          * sets the label used on all file below the mountpoint, and will set
 868          * the superblock context if not already set.
 869          */
 870         if (kern_flags & SECURITY_LSM_NATIVE_LABELS && !context_sid) {
 871                 sbsec->behavior = SECURITY_FS_USE_NATIVE;
 872                 *set_kern_flags |= SECURITY_LSM_NATIVE_LABELS;
 873         }
 874
 875         if (context_sid) {
 876                 if (!fscontext_sid) {
 877                         rc = may_context_mount_sb_relabel(context_sid, sbsec,
 878                                                           cred);
 879                         if (rc)
 880                                 goto out;
 881                         sbsec->sid = context_sid;
 882                 } else {
 883                         rc = may_context_mount_inode_relabel(context_sid, sbsec,
 884                                                              cred);
 885                         if (rc)
 886                                 goto out;
 887                 }
 888                 if (!rootcontext_sid)
 889                         rootcontext_sid = context_sid;
 890
 891                 sbsec->mntpoint_sid = context_sid;
 892                 sbsec->behavior = SECURITY_FS_USE_MNTPOINT;
 893         }
 894
 895         if (rootcontext_sid) {
 896                 rc = may_context_mount_inode_relabel(rootcontext_sid, sbsec,
 897                                                      cred);
 898                 if (rc)
 899                         goto out;
 900
 901                 root_isec->sid = rootcontext_sid;
 902                 root_isec->initialized = LABEL_INITIALIZED;
 903         }
 904
 905         if (defcontext_sid) {
 906                 if (sbsec->behavior != SECURITY_FS_USE_XATTR &&
 907                         sbsec->behavior != SECURITY_FS_USE_NATIVE) {
 908                         rc = -EINVAL;
 909                         printk(KERN_WARNING "SELinux: defcontext option is "
 910                                "invalid for this filesystem type\n");
 911                         goto out;
 912                 }
 913
 914                 if (defcontext_sid != sbsec->def_sid) {
 915                         rc = may_context_mount_inode_relabel(defcontext_sid,
 916                                                              sbsec, cred);
 917                         if (rc)
 918                                 goto out;
 919                 }
 920
 921                 sbsec->def_sid = defcontext_sid;
 922         }
 923
 924 out_set_opts:
 925         rc = sb_finish_set_opts(sb);
 926 out:
 927         mutex_unlock(&sbsec->lock);
 928         return rc;
 929 out_double_mount:
 930         rc = -EINVAL;
 931         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, different "
 932                "security settings for (dev %s, type %s)\n", sb->s_id, name);
 933         goto out;
 934 }
 935
 936 static int selinux_cmp_sb_context(const struct super_block *oldsb,
 937                                     const struct super_block *newsb)
 938 {
 939         struct superblock_security_struct *old = oldsb->s_security;
 940         struct superblock_security_struct *new = newsb->s_security;
 941         char oldflags = old->flags & SE_MNTMASK;
 942         char newflags = new->flags & SE_MNTMASK;
 943
 944         if (oldflags != newflags)
 945                 goto mismatch;
 946         if ((oldflags & FSCONTEXT_MNT) && old->sid != new->sid)
 947                 goto mismatch;
 948         if ((oldflags & CONTEXT_MNT) && old->mntpoint_sid != new->mntpoint_sid)
 949                 goto mismatch;
 950         if ((oldflags & DEFCONTEXT_MNT) && old->def_sid != new->def_sid)
 951                 goto mismatch;
 952         if (oldflags & ROOTCONTEXT_MNT) {
 953                 struct inode_security_struct *oldroot = backing_inode_security(oldsb->s_root);
 954                 struct inode_security_struct *newroot = backing_inode_security(newsb->s_root);
 955                 if (oldroot->sid != newroot->sid)
 956                         goto mismatch;
 957         }
 958         return 0;
 959 mismatch:
 960         printk(KERN_WARNING "SELinux: mount invalid.  Same superblock, "
 961                             "different security settings for (dev %s, "
 962                             "type %s)\n", newsb->s_id, newsb->s_type->name);
 963         return -EBUSY;
 964 }
 965
 966 static int selinux_sb_clone_mnt_opts(const struct super_block *oldsb,
 967                                         struct super_block *newsb)
 968 {
 969         const struct superblock_security_struct *oldsbsec = oldsb->s_security;
 970         struct superblock_security_struct *newsbsec = newsb->s_security;
 971
 972         int set_fscontext =     (oldsbsec->flags & FSCONTEXT_MNT);
 973         int set_context =       (oldsbsec->flags & CONTEXT_MNT);
 974         int set_rootcontext =   (oldsbsec->flags & ROOTCONTEXT_MNT);
 975
 976         /*
 977          * if the parent was able to be mounted it clearly had no special lsm
 978          * mount options.  thus we can safely deal with this superblock later
 979          */
 980         if (!ss_initialized)
 981                 return 0;
 982
 983         /* how can we clone if the old one wasn't set up?? */
 984         BUG_ON(!(oldsbsec->flags & SE_SBINITIALIZED));
 985
 986         /* if fs is reusing a sb, make sure that the contexts match */
 987         if (newsbsec->flags & SE_SBINITIALIZED)
 988                 return selinux_cmp_sb_context(oldsb, newsb);
 989
 990         mutex_lock(&newsbsec->lock);
 991
 992         newsbsec->flags = oldsbsec->flags;
 993
 994         newsbsec->sid = oldsbsec->sid;
 995         newsbsec->def_sid = oldsbsec->def_sid;
 996         newsbsec->behavior = oldsbsec->behavior;
 997
 998         if (set_context) {
 999                 u32 sid = oldsbsec->mntpoint_sid;
1000
1001                 if (!set_fscontext)
1002                         newsbsec->sid = sid;
1003                 if (!set_rootcontext) {
1004                         struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
1005                         newisec->sid = sid;
1006                 }
1007                 newsbsec->mntpoint_sid = sid;
1008         }
1009         if (set_rootcontext) {
1010                 const struct inode_security_struct *oldisec = backing_inode_security(oldsb->s_root);
1011                 struct inode_security_struct *newisec = backing_inode_security(newsb->s_root);
1012
1013                 newisec->sid = oldisec->sid;
1014         }
1015
1016         sb_finish_set_opts(newsb);
1017         mutex_unlock(&newsbsec->lock);
1018         return 0;
1019 }
1020
1021 static int selinux_parse_opts_str(char *options,
1022                                   struct security_mnt_opts *opts)
1023 {
1024         char *p;
1025         char *context = NULL, *defcontext = NULL;
1026         char *fscontext = NULL, *rootcontext = NULL;
1027         int rc, num_mnt_opts = 0;
1028
1029         opts->num_mnt_opts = 0;
1030
1031         /* Standard string-based options. */
1032         while ((p = strsep(&options, "|")) != NULL) {
1033                 int token;
1034                 substring_t args[MAX_OPT_ARGS];
1035
1036                 if (!*p)
1037                         continue;
1038
1039                 token = match_token(p, tokens, args);
1040
1041                 switch (token) {
1042                 case Opt_context:
1043                         if (context || defcontext) {
1044                                 rc = -EINVAL;
1045                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1046                                 goto out_err;
1047                         }
1048                         context = match_strdup(&args[0]);
1049                         if (!context) {
1050                                 rc = -ENOMEM;
1051                                 goto out_err;
1052                         }
1053                         break;
1054
1055                 case Opt_fscontext:
1056                         if (fscontext) {
1057                                 rc = -EINVAL;
1058                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1059                                 goto out_err;
1060                         }
1061                         fscontext = match_strdup(&args[0]);
1062                         if (!fscontext) {
1063                                 rc = -ENOMEM;
1064                                 goto out_err;
1065                         }
1066                         break;
1067
1068                 case Opt_rootcontext:
1069                         if (rootcontext) {
1070                                 rc = -EINVAL;
1071                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1072                                 goto out_err;
1073                         }
1074                         rootcontext = match_strdup(&args[0]);
1075                         if (!rootcontext) {
1076                                 rc = -ENOMEM;
1077                                 goto out_err;
1078                         }
1079                         break;
1080
1081                 case Opt_defcontext:
1082                         if (context || defcontext) {
1083                                 rc = -EINVAL;
1084                                 printk(KERN_WARNING SEL_MOUNT_FAIL_MSG);
1085                                 goto out_err;
1086                         }
1087                         defcontext = match_strdup(&args[0]);
1088                         if (!defcontext) {
1089                                 rc = -ENOMEM;
1090                                 goto out_err;
1091                         }
1092                         break;
1093                 case Opt_labelsupport:
1094                         break;
1095                 default:
1096                         rc = -EINVAL;
1097                         printk(KERN_WARNING "SELinux:  unknown mount option\n");
1098                         goto out_err;
1099
1100                 }
1101         }
1102
1103         rc = -ENOMEM;
1104         opts->mnt_opts = kcalloc(NUM_SEL_MNT_OPTS, sizeof(char *), GFP_KERNEL);
1105         if (!opts->mnt_opts)
1106                 goto out_err;
1107
1108         opts->mnt_opts_flags = kcalloc(NUM_SEL_MNT_OPTS, sizeof(int),
1109                                        GFP_KERNEL);
1110         if (!opts->mnt_opts_flags) {
1111                 kfree(opts->mnt_opts);
1112                 goto out_err;
1113         }
1114
1115         if (fscontext) {
1116                 opts->mnt_opts[num_mnt_opts] = fscontext;
1117                 opts->mnt_opts_flags[num_mnt_opts++] = FSCONTEXT_MNT;
1118         }
1119         if (context) {
1120                 opts->mnt_opts[num_mnt_opts] = context;
1121                 opts->mnt_opts_flags[num_mnt_opts++] = CONTEXT_MNT;
1122         }
1123         if (rootcontext) {
1124                 opts->mnt_opts[num_mnt_opts] = rootcontext;
1125                 opts->mnt_opts_flags[num_mnt_opts++] = ROOTCONTEXT_MNT;
1126         }
1127         if (defcontext) {
1128                 opts->mnt_opts[num_mnt_opts] = defcontext;
1129                 opts->mnt_opts_flags[num_mnt_opts++] = DEFCONTEXT_MNT;
1130         }
1131
1132         opts->num_mnt_opts = num_mnt_opts;
1133         return 0;
1134
1135 out_err:
1136         kfree(context);
1137         kfree(defcontext);
1138         kfree(fscontext);
1139         kfree(rootcontext);
1140         return rc;
1141 }
1142 /*
1143  * string mount options parsing and call set the sbsec
1144  */
1145 static int superblock_doinit(struct super_block *sb, void *data)
1146 {
1147         int rc = 0;
1148         char *options = data;
1149         struct security_mnt_opts opts;
1150
1151         security_init_mnt_opts(&opts);
1152
1153         if (!data)
1154                 goto out;
1155
1156         BUG_ON(sb->s_type->fs_flags & FS_BINARY_MOUNTDATA);
1157
1158         rc = selinux_parse_opts_str(options, &opts);
1159         if (rc)
1160                 goto out_err;
1161
1162 out:
1163         rc = selinux_set_mnt_opts(sb, &opts, 0, NULL);
1164
1165 out_err:
1166         security_free_mnt_opts(&opts);
1167         return rc;
1168 }
1169
1170 static void selinux_write_opts(struct seq_file *m,
1171                                struct security_mnt_opts *opts)
1172 {
1173         int i;
1174         char *prefix;
1175
1176         for (i = 0; i < opts->num_mnt_opts; i++) {
1177                 char *has_comma;
1178
1179                 if (opts->mnt_opts[i])
1180                         has_comma = strchr(opts->mnt_opts[i], ',');
1181                 else
1182                         has_comma = NULL;
1183
1184                 switch (opts->mnt_opts_flags[i]) {
1185                 case CONTEXT_MNT:
1186                         prefix = CONTEXT_STR;
1187                         break;
1188                 case FSCONTEXT_MNT:
1189                         prefix = FSCONTEXT_STR;
1190                         break;
1191                 case ROOTCONTEXT_MNT:
1192                         prefix = ROOTCONTEXT_STR;
1193                         break;
1194                 case DEFCONTEXT_MNT:
1195                         prefix = DEFCONTEXT_STR;
1196                         break;
1197                 case SBLABEL_MNT:
1198                         seq_putc(m, ',');
1199                         seq_puts(m, LABELSUPP_STR);
1200                         continue;
1201                 default:
1202                         BUG();
1203                         return;
1204                 };
1205                 /* we need a comma before each option */
1206                 seq_putc(m, ',');
1207                 seq_puts(m, prefix);
1208                 if (has_comma)
1209                         seq_putc(m, '\"');
1210                 seq_escape(m, opts->mnt_opts[i], "\"\n\\");
1211                 if (has_comma)
1212                         seq_putc(m, '\"');
1213         }
1214 }
1215
1216 static int selinux_sb_show_options(struct seq_file *m, struct super_block *sb)
1217 {
1218         struct security_mnt_opts opts;
1219         int rc;
1220
1221         rc = selinux_get_mnt_opts(sb, &opts);
1222         if (rc) {
1223                 /* before policy load we may get EINVAL, don't show anything */
1224                 if (rc == -EINVAL)
1225                         rc = 0;
1226                 return rc;
1227         }
1228
1229         selinux_write_opts(m, &opts);
1230
1231         security_free_mnt_opts(&opts);
1232
1233         return rc;
1234 }
1235
1236 static inline u16 inode_mode_to_security_class(umode_t mode)
1237 {
1238         switch (mode & S_IFMT) {
1239         case S_IFSOCK:
1240                 return SECCLASS_SOCK_FILE;
1241         case S_IFLNK:
1242                 return SECCLASS_LNK_FILE;
1243         case S_IFREG:
1244                 return SECCLASS_FILE;
1245         case S_IFBLK:
1246                 return SECCLASS_BLK_FILE;
1247         case S_IFDIR:
1248                 return SECCLASS_DIR;
1249         case S_IFCHR:
1250                 return SECCLASS_CHR_FILE;
1251         case S_IFIFO:
1252                 return SECCLASS_FIFO_FILE;
1253
1254         }
1255
1256         return SECCLASS_FILE;
1257 }
1258
1259 static inline int default_protocol_stream(int protocol)
1260 {
1261         return (protocol == IPPROTO_IP || protocol == IPPROTO_TCP);
1262 }
1263
1264 static inline int default_protocol_dgram(int protocol)
1265 {
1266         return (protocol == IPPROTO_IP || protocol == IPPROTO_UDP);
1267 }
1268
1269 static inline u16 socket_type_to_security_class(int family, int type, int protocol)
1270 {
1271         switch (family) {
1272         case PF_UNIX:
1273                 switch (type) {
1274                 case SOCK_STREAM:
1275                 case SOCK_SEQPACKET:
1276                         return SECCLASS_UNIX_STREAM_SOCKET;
1277                 case SOCK_DGRAM:
1278                         return SECCLASS_UNIX_DGRAM_SOCKET;
1279                 }
1280                 break;
1281         case PF_INET:
1282         case PF_INET6:
1283                 switch (type) {
1284                 case SOCK_STREAM:
1285                         if (default_protocol_stream(protocol))
1286                                 return SECCLASS_TCP_SOCKET;
1287                         else
1288                                 return SECCLASS_RAWIP_SOCKET;
1289                 case SOCK_DGRAM:
1290                         if (default_protocol_dgram(protocol))
1291                                 return SECCLASS_UDP_SOCKET;
1292                         else
1293                                 return SECCLASS_RAWIP_SOCKET;
1294                 case SOCK_DCCP:
1295                         return SECCLASS_DCCP_SOCKET;
1296                 default:
1297                         return SECCLASS_RAWIP_SOCKET;
1298                 }
1299                 break;
1300         case PF_NETLINK:
1301                 switch (protocol) {
1302                 case NETLINK_ROUTE:
1303                         return SECCLASS_NETLINK_ROUTE_SOCKET;
1304                 case NETLINK_SOCK_DIAG:
1305                         return SECCLASS_NETLINK_TCPDIAG_SOCKET;
1306                 case NETLINK_NFLOG:
1307                         return SECCLASS_NETLINK_NFLOG_SOCKET;
1308                 case NETLINK_XFRM:
1309                         return SECCLASS_NETLINK_XFRM_SOCKET;
1310                 case NETLINK_SELINUX:
1311                         return SECCLASS_NETLINK_SELINUX_SOCKET;
1312                 case NETLINK_ISCSI:
1313                         return SECCLASS_NETLINK_ISCSI_SOCKET;
1314                 case NETLINK_AUDIT:
1315                         return SECCLASS_NETLINK_AUDIT_SOCKET;
1316                 case NETLINK_FIB_LOOKUP:
1317                         return SECCLASS_NETLINK_FIB_LOOKUP_SOCKET;
1318                 case NETLINK_CONNECTOR:
1319                         return SECCLASS_NETLINK_CONNECTOR_SOCKET;
1320                 case NETLINK_NETFILTER:
1321                         return SECCLASS_NETLINK_NETFILTER_SOCKET;
1322                 case NETLINK_DNRTMSG:
1323                         return SECCLASS_NETLINK_DNRT_SOCKET;
1324                 case NETLINK_KOBJECT_UEVENT:
1325                         return SECCLASS_NETLINK_KOBJECT_UEVENT_SOCKET;
1326                 case NETLINK_GENERIC:
1327                         return SECCLASS_NETLINK_GENERIC_SOCKET;
1328                 case NETLINK_SCSITRANSPORT:
1329                         return SECCLASS_NETLINK_SCSITRANSPORT_SOCKET;
1330                 case NETLINK_RDMA:
1331                         return SECCLASS_NETLINK_RDMA_SOCKET;
1332                 case NETLINK_CRYPTO:
1333                         return SECCLASS_NETLINK_CRYPTO_SOCKET;
1334                 default:
1335                         return SECCLASS_NETLINK_SOCKET;
1336                 }
1337         case PF_PACKET:
1338                 return SECCLASS_PACKET_SOCKET;
1339         case PF_KEY:
1340                 return SECCLASS_KEY_SOCKET;
1341         case PF_APPLETALK:
1342                 return SECCLASS_APPLETALK_SOCKET;
1343         }
1344
1345         return SECCLASS_SOCKET;
1346 }
1347
1348 static int selinux_genfs_get_sid(struct dentry *dentry,
1349                                  u16 tclass,
1350                                  u16 flags,
1351                                  u32 *sid)
1352 {
1353         int rc;
1354         struct super_block *sb = dentry->d_sb;
1355         char *buffer, *path;
1356
1357         buffer = (char *)__get_free_page(GFP_KERNEL);
1358         if (!buffer)
1359                 return -ENOMEM;
1360
1361         path = dentry_path_raw(dentry, buffer, PAGE_SIZE);
1362         if (IS_ERR(path))
1363                 rc = PTR_ERR(path);
1364         else {
1365                 if (flags & SE_SBPROC) {
1366                         /* each process gets a /proc/PID/ entry. Strip off the
1367                          * PID part to get a valid selinux labeling.
1368                          * e.g. /proc/1/net/rpc/nfs -> /net/rpc/nfs */
1369                         while (path[1] >= '0' && path[1] <= '9') {
1370                                 path[1] = '/';
1371                                 path++;
1372                         }
1373                 }
1374                 rc = security_genfs_sid(sb->s_type->name, path, tclass, sid);
1375         }
1376         free_page((unsigned long)buffer);
1377         return rc;
1378 }
1379
1380 /* The inode's security attributes must be initialized before first use. */
1381 static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dentry)
1382 {
1383         struct superblock_security_struct *sbsec = NULL;
1384         struct inode_security_struct *isec = inode->i_security;
1385         u32 task_sid, sid = 0;
1386         u16 sclass;
1387         struct dentry *dentry;
1388 #define INITCONTEXTLEN 255
1389         char *context = NULL;
1390         unsigned len = 0;
1391         int rc = 0;
1392
1393         if (isec->initialized == LABEL_INITIALIZED)
1394                 return 0;
1395
1396         spin_lock(&isec->lock);
1397         if (isec->initialized == LABEL_INITIALIZED)
1398                 goto out_unlock;
1399
1400         if (isec->sclass == SECCLASS_FILE)
1401                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
1402
1403         sbsec = inode->i_sb->s_security;
1404         if (!(sbsec->flags & SE_SBINITIALIZED)) {
1405                 /* Defer initialization until selinux_complete_init,
1406                    after the initial policy is loaded and the security
1407                    server is ready to handle calls. */
1408                 spin_lock(&sbsec->isec_lock);
1409                 if (list_empty(&isec->list))
1410                         list_add(&isec->list, &sbsec->isec_head);
1411                 spin_unlock(&sbsec->isec_lock);
1412                 goto out_unlock;
1413         }
1414
1415         sclass = isec->sclass;
1416         task_sid = isec->task_sid;
1417         sid = isec->sid;
1418         isec->initialized = LABEL_PENDING;
1419         spin_unlock(&isec->lock);
1420
1421         switch (sbsec->behavior) {
1422         case SECURITY_FS_USE_NATIVE:
1423                 break;
1424         case SECURITY_FS_USE_XATTR:
1425                 if (!(inode->i_opflags & IOP_XATTR)) {
1426                         sid = sbsec->def_sid;
1427                         break;
1428                 }
1429                 /* Need a dentry, since the xattr API requires one.
1430                    Life would be simpler if we could just pass the inode. */
1431                 if (opt_dentry) {
1432                         /* Called from d_instantiate or d_splice_alias. */
1433                         dentry = dget(opt_dentry);
1434                 } else {
1435                         /* Called from selinux_complete_init, try to find a dentry. */
1436                         dentry = d_find_alias(inode);
1437                 }
1438                 if (!dentry) {
1439                         /*
1440                          * this is can be hit on boot when a file is accessed
1441                          * before the policy is loaded.  When we load policy we
1442                          * may find inodes that have no dentry on the
1443                          * sbsec->isec_head list.  No reason to complain as these
1444                          * will get fixed up the next time we go through
1445                          * inode_doinit with a dentry, before these inodes could
1446                          * be used again by userspace.
1447                          */
1448                         goto out;
1449                 }
1450
1451                 len = INITCONTEXTLEN;
1452                 context = kmalloc(len+1, GFP_NOFS);
1453                 if (!context) {
1454                         rc = -ENOMEM;
1455                         dput(dentry);
1456                         goto out;
1457                 }
1458                 context[len] = '\0';
1459                 rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1460                 if (rc == -ERANGE) {
1461                         kfree(context);
1462
1463                         /* Need a larger buffer.  Query for the right size. */
1464                         rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, NULL, 0);
1465                         if (rc < 0) {
1466                                 dput(dentry);
1467                                 goto out;
1468                         }
1469                         len = rc;
1470                         context = kmalloc(len+1, GFP_NOFS);
1471                         if (!context) {
1472                                 rc = -ENOMEM;
1473                                 dput(dentry);
1474                                 goto out;
1475                         }
1476                         context[len] = '\0';
1477                         rc = __vfs_getxattr(dentry, inode, XATTR_NAME_SELINUX, context, len);
1478                 }
1479                 dput(dentry);
1480                 if (rc < 0) {
1481                         if (rc != -ENODATA) {
1482                                 printk(KERN_WARNING "SELinux: %s:  getxattr returned "
1483                                        "%d for dev=%s ino=%ld\n", __func__,
1484                                        -rc, inode->i_sb->s_id, inode->i_ino);
1485                                 kfree(context);
1486                                 goto out;
1487                         }
1488                         /* Map ENODATA to the default file SID */
1489                         sid = sbsec->def_sid;
1490                         rc = 0;
1491                 } else {
1492                         rc = security_context_to_sid_default(context, rc, &sid,
1493                                                              sbsec->def_sid,
1494                                                              GFP_NOFS);
1495                         if (rc) {
1496                                 char *dev = inode->i_sb->s_id;
1497                                 unsigned long ino = inode->i_ino;
1498
1499                                 if (rc == -EINVAL) {
1500                                         if (printk_ratelimit())
1501                                                 printk(KERN_NOTICE "SELinux: inode=%lu on dev=%s was found to have an invalid "
1502                                                         "context=%s.  This indicates you may need to relabel the inode or the "
1503                                                         "filesystem in question.\n", ino, dev, context);
1504                                 } else {
1505                                         printk(KERN_WARNING "SELinux: %s:  context_to_sid(%s) "
1506                                                "returned %d for dev=%s ino=%ld\n",
1507                                                __func__, context, -rc, dev, ino);
1508                                 }
1509                                 kfree(context);
1510                                 /* Leave with the unlabeled SID */
1511                                 rc = 0;
1512                                 break;
1513                         }
1514                 }
1515                 kfree(context);
1516                 break;
1517         case SECURITY_FS_USE_TASK:
1518                 sid = task_sid;
1519                 break;
1520         case SECURITY_FS_USE_TRANS:
1521                 /* Default to the fs SID. */
1522                 sid = sbsec->sid;
1523
1524                 /* Try to obtain a transition SID. */
1525                 rc = security_transition_sid(task_sid, sid, sclass, NULL, &sid);
1526                 if (rc)
1527                         goto out;
1528                 break;
1529         case SECURITY_FS_USE_MNTPOINT:
1530                 sid = sbsec->mntpoint_sid;
1531                 break;
1532         default:
1533                 /* Default to the fs superblock SID. */
1534                 sid = sbsec->sid;
1535
1536                 if ((sbsec->flags & SE_SBGENFS) && !S_ISLNK(inode->i_mode)) {
1537                         /* We must have a dentry to determine the label on
1538                          * procfs inodes */
1539                         if (opt_dentry)
1540                                 /* Called from d_instantiate or
1541                                  * d_splice_alias. */
1542                                 dentry = dget(opt_dentry);
1543                         else
1544                                 /* Called from selinux_complete_init, try to
1545                                  * find a dentry. */
1546                                 dentry = d_find_alias(inode);
1547                         /*
1548                          * This can be hit on boot when a file is accessed
1549                          * before the policy is loaded.  When we load policy we
1550                          * may find inodes that have no dentry on the
1551                          * sbsec->isec_head list.  No reason to complain as
1552                          * these will get fixed up the next time we go through
1553                          * inode_doinit() with a dentry, before these inodes
1554                          * could be used again by userspace.
1555                          */
1556                         if (!dentry)
1557                                 goto out;
1558                         rc = selinux_genfs_get_sid(dentry, sclass,
1559                                                    sbsec->flags, &sid);
1560                         dput(dentry);
1561                         if (rc)
1562                                 goto out;
1563                 }
1564                 break;
1565         }
1566
1567 out:
1568         spin_lock(&isec->lock);
1569         if (isec->initialized == LABEL_PENDING) {
1570                 if (!sid || rc) {
1571                         isec->initialized = LABEL_INVALID;
1572                         goto out_unlock;
1573                 }
1574
1575                 isec->initialized = LABEL_INITIALIZED;
1576                 isec->sid = sid;
1577         }
1578
1579 out_unlock:
1580         spin_unlock(&isec->lock);
1581         return rc;
1582 }
1583
1584 /* Convert a Linux signal to an access vector. */
1585 static inline u32 signal_to_av(int sig)
1586 {
1587         u32 perm = 0;
1588
1589         switch (sig) {
1590         case SIGCHLD:
1591                 /* Commonly granted from child to parent. */
1592                 perm = PROCESS__SIGCHLD;
1593                 break;
1594         case SIGKILL:
1595                 /* Cannot be caught or ignored */
1596                 perm = PROCESS__SIGKILL;
1597                 break;
1598         case SIGSTOP:
1599                 /* Cannot be caught or ignored */
1600                 perm = PROCESS__SIGSTOP;
1601                 break;
1602         default:
1603                 /* All other signals. */
1604                 perm = PROCESS__SIGNAL;
1605                 break;
1606         }
1607
1608         return perm;
1609 }
1610
1611 /*
1612  * Check permission between a pair of credentials
1613  * fork check, ptrace check, etc.
1614  */
1615 static int cred_has_perm(const struct cred *actor,
1616                          const struct cred *target,
1617                          u32 perms)
1618 {
1619         u32 asid = cred_sid(actor), tsid = cred_sid(target);
1620
1621         return avc_has_perm(asid, tsid, SECCLASS_PROCESS, perms, NULL);
1622 }
1623
1624 /*
1625  * Check permission between a pair of tasks, e.g. signal checks,
1626  * fork check, ptrace check, etc.
1627  * tsk1 is the actor and tsk2 is the target
1628  * - this uses the default subjective creds of tsk1
1629  */
1630 static int task_has_perm(const struct task_struct *tsk1,
1631                          const struct task_struct *tsk2,
1632                          u32 perms)
1633 {
1634         const struct task_security_struct *__tsec1, *__tsec2;
1635         u32 sid1, sid2;
1636
1637         rcu_read_lock();
1638         __tsec1 = __task_cred(tsk1)->security;  sid1 = __tsec1->sid;
1639         __tsec2 = __task_cred(tsk2)->security;  sid2 = __tsec2->sid;
1640         rcu_read_unlock();
1641         return avc_has_perm(sid1, sid2, SECCLASS_PROCESS, perms, NULL);
1642 }
1643
1644 /*
1645  * Check permission between current and another task, e.g. signal checks,
1646  * fork check, ptrace check, etc.
1647  * current is the actor and tsk2 is the target
1648  * - this uses current's subjective creds
1649  */
1650 static int current_has_perm(const struct task_struct *tsk,
1651                             u32 perms)
1652 {
1653         u32 sid, tsid;
1654
1655         sid = current_sid();
1656         tsid = task_sid(tsk);
1657         return avc_has_perm(sid, tsid, SECCLASS_PROCESS, perms, NULL);
1658 }
1659
1660 #if CAP_LAST_CAP > 63
1661 #error Fix SELinux to handle capabilities > 63.
1662 #endif
1663
1664 /* Check whether a task is allowed to use a capability. */
1665 static int cred_has_capability(const struct cred *cred,
1666                                int cap, int audit, bool initns)
1667 {
1668         struct common_audit_data ad;
1669         struct av_decision avd;
1670         u16 sclass;
1671         u32 sid = cred_sid(cred);
1672         u32 av = CAP_TO_MASK(cap);
1673         int rc;
1674
1675         ad.type = LSM_AUDIT_DATA_CAP;
1676         ad.u.cap = cap;
1677
1678         switch (CAP_TO_INDEX(cap)) {
1679         case 0:
1680                 sclass = initns ? SECCLASS_CAPABILITY : SECCLASS_CAP_USERNS;
1681                 break;
1682         case 1:
1683                 sclass = initns ? SECCLASS_CAPABILITY2 : SECCLASS_CAP2_USERNS;
1684                 break;
1685         default:
1686                 printk(KERN_ERR
1687                        "SELinux:  out of range capability %d\n", cap);
1688                 BUG();
1689                 return -EINVAL;
1690         }
1691
1692         rc = avc_has_perm_noaudit(sid, sid, sclass, av, 0, &avd);
1693         if (audit == SECURITY_CAP_AUDIT) {
1694                 int rc2 = avc_audit(sid, sid, sclass, av, &avd, rc, &ad, 0);
1695                 if (rc2)
1696                         return rc2;
1697         }
1698         return rc;
1699 }
1700
1701 /* Check whether a task is allowed to use a system operation. */
1702 static int task_has_system(struct task_struct *tsk,
1703                            u32 perms)
1704 {
1705         u32 sid = task_sid(tsk);
1706
1707         return avc_has_perm(sid, SECINITSID_KERNEL,
1708                             SECCLASS_SYSTEM, perms, NULL);
1709 }
1710
1711 /* Check whether a task has a particular permission to an inode.
1712    The 'adp' parameter is optional and allows other audit
1713    data to be passed (e.g. the dentry). */
1714 static int inode_has_perm(const struct cred *cred,
1715                           struct inode *inode,
1716                           u32 perms,
1717                           struct common_audit_data *adp)
1718 {
1719         struct inode_security_struct *isec;
1720         u32 sid;
1721
1722         validate_creds(cred);
1723
1724         if (unlikely(IS_PRIVATE(inode)))
1725                 return 0;
1726
1727         sid = cred_sid(cred);
1728         isec = inode->i_security;
1729
1730         return avc_has_perm(sid, isec->sid, isec->sclass, perms, adp);
1731 }
1732
1733 /* Same as inode_has_perm, but pass explicit audit data containing
1734    the dentry to help the auditing code to more easily generate the
1735    pathname if needed. */
1736 static inline int dentry_has_perm(const struct cred *cred,
1737                                   struct dentry *dentry,
1738                                   u32 av)
1739 {
1740         struct inode *inode = d_backing_inode(dentry);
1741         struct common_audit_data ad;
1742
1743         ad.type = LSM_AUDIT_DATA_DENTRY;
1744         ad.u.dentry = dentry;
1745         __inode_security_revalidate(inode, dentry, true);
1746         return inode_has_perm(cred, inode, av, &ad);
1747 }
1748
1749 /* Same as inode_has_perm, but pass explicit audit data containing
1750    the path to help the auditing code to more easily generate the
1751    pathname if needed. */
1752 static inline int path_has_perm(const struct cred *cred,
1753                                 const struct path *path,
1754                                 u32 av)
1755 {
1756         struct inode *inode = d_backing_inode(path->dentry);
1757         struct common_audit_data ad;
1758
1759         ad.type = LSM_AUDIT_DATA_PATH;
1760         ad.u.path = *path;
1761         __inode_security_revalidate(inode, path->dentry, true);
1762         return inode_has_perm(cred, inode, av, &ad);
1763 }
1764
1765 /* Same as path_has_perm, but uses the inode from the file struct. */
1766 static inline int file_path_has_perm(const struct cred *cred,
1767                                      struct file *file,
1768                                      u32 av)
1769 {
1770         struct common_audit_data ad;
1771
1772         ad.type = LSM_AUDIT_DATA_FILE;
1773         ad.u.file = file;
1774         return inode_has_perm(cred, file_inode(file), av, &ad);
1775 }
1776
1777 /* Check whether a task can use an open file descriptor to
1778    access an inode in a given way.  Check access to the
1779    descriptor itself, and then use dentry_has_perm to
1780    check a particular permission to the file.
1781    Access to the descriptor is implicitly granted if it
1782    has the same SID as the process.  If av is zero, then
1783    access to the file is not checked, e.g. for cases
1784    where only the descriptor is affected like seek. */
1785 static int file_has_perm(const struct cred *cred,
1786                          struct file *file,
1787                          u32 av)
1788 {
1789         struct file_security_struct *fsec = file->f_security;
1790         struct inode *inode = file_inode(file);
1791         struct common_audit_data ad;
1792         u32 sid = cred_sid(cred);
1793         int rc;
1794
1795         ad.type = LSM_AUDIT_DATA_FILE;
1796         ad.u.file = file;
1797
1798         if (sid != fsec->sid) {
1799                 rc = avc_has_perm(sid, fsec->sid,
1800                                   SECCLASS_FD,
1801                                   FD__USE,
1802                                   &ad);
1803                 if (rc)
1804                         goto out;
1805         }
1806
1807         /* av is zero if only checking access to the descriptor. */
1808         rc = 0;
1809         if (av)
1810                 rc = inode_has_perm(cred, inode, av, &ad);
1811
1812 out:
1813         return rc;
1814 }
1815
1816 /*
1817  * Determine the label for an inode that might be unioned.
1818  */
1819 static int
1820 selinux_determine_inode_label(const struct task_security_struct *tsec,
1821                                  struct inode *dir,
1822                                  const struct qstr *name, u16 tclass,
1823                                  u32 *_new_isid)
1824 {
1825         const struct superblock_security_struct *sbsec = dir->i_sb->s_security;
1826
1827         if ((sbsec->flags & SE_SBINITIALIZED) &&
1828             (sbsec->behavior == SECURITY_FS_USE_MNTPOINT)) {
1829                 *_new_isid = sbsec->mntpoint_sid;
1830         } else if ((sbsec->flags & SBLABEL_MNT) &&
1831                    tsec->create_sid) {
1832                 *_new_isid = tsec->create_sid;
1833         } else {
1834                 const struct inode_security_struct *dsec = inode_security(dir);
1835                 return security_transition_sid(tsec->sid, dsec->sid, tclass,
1836                                                name, _new_isid);
1837         }
1838
1839         return 0;
1840 }
1841
1842 /* Check whether a task can create a file. */
1843 static int may_create(struct inode *dir,
1844                       struct dentry *dentry,
1845                       u16 tclass)
1846 {
1847         const struct task_security_struct *tsec = current_security();
1848         struct inode_security_struct *dsec;
1849         struct superblock_security_struct *sbsec;
1850         u32 sid, newsid;
1851         struct common_audit_data ad;
1852         int rc;
1853
1854         dsec = inode_security(dir);
1855         sbsec = dir->i_sb->s_security;
1856
1857         sid = tsec->sid;
1858
1859         ad.type = LSM_AUDIT_DATA_DENTRY;
1860         ad.u.dentry = dentry;
1861
1862         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR,
1863                           DIR__ADD_NAME | DIR__SEARCH,
1864                           &ad);
1865         if (rc)
1866                 return rc;
1867
1868         rc = selinux_determine_inode_label(current_security(), dir,
1869                                            &dentry->d_name, tclass, &newsid);
1870         if (rc)
1871                 return rc;
1872
1873         rc = avc_has_perm(sid, newsid, tclass, FILE__CREATE, &ad);
1874         if (rc)
1875                 return rc;
1876
1877         return avc_has_perm(newsid, sbsec->sid,
1878                             SECCLASS_FILESYSTEM,
1879                             FILESYSTEM__ASSOCIATE, &ad);
1880 }
1881
1882 /* Check whether a task can create a key. */
1883 static int may_create_key(u32 ksid,
1884                           struct task_struct *ctx)
1885 {
1886         u32 sid = task_sid(ctx);
1887
1888         return avc_has_perm(sid, ksid, SECCLASS_KEY, KEY__CREATE, NULL);
1889 }
1890
1891 #define MAY_LINK        0
1892 #define MAY_UNLINK      1
1893 #define MAY_RMDIR       2
1894
1895 /* Check whether a task can link, unlink, or rmdir a file/directory. */
1896 static int may_link(struct inode *dir,
1897                     struct dentry *dentry,
1898                     int kind)
1899
1900 {
1901         struct inode_security_struct *dsec, *isec;
1902         struct common_audit_data ad;
1903         u32 sid = current_sid();
1904         u32 av;
1905         int rc;
1906
1907         dsec = inode_security(dir);
1908         isec = backing_inode_security(dentry);
1909
1910         ad.type = LSM_AUDIT_DATA_DENTRY;
1911         ad.u.dentry = dentry;
1912
1913         av = DIR__SEARCH;
1914         av |= (kind ? DIR__REMOVE_NAME : DIR__ADD_NAME);
1915         rc = avc_has_perm(sid, dsec->sid, SECCLASS_DIR, av, &ad);
1916         if (rc)
1917                 return rc;
1918
1919         switch (kind) {
1920         case MAY_LINK:
1921                 av = FILE__LINK;
1922                 break;
1923         case MAY_UNLINK:
1924                 av = FILE__UNLINK;
1925                 break;
1926         case MAY_RMDIR:
1927                 av = DIR__RMDIR;
1928                 break;
1929         default:
1930                 printk(KERN_WARNING "SELinux: %s:  unrecognized kind %d\n",
1931                         __func__, kind);
1932                 return 0;
1933         }
1934
1935         rc = avc_has_perm(sid, isec->sid, isec->sclass, av, &ad);
1936         return rc;
1937 }
1938
1939 static inline int may_rename(struct inode *old_dir,
1940                              struct dentry *old_dentry,
1941                              struct inode *new_dir,
1942                              struct dentry *new_dentry)
1943 {
1944         struct inode_security_struct *old_dsec, *new_dsec, *old_isec, *new_isec;
1945         struct common_audit_data ad;
1946         u32 sid = current_sid();
1947         u32 av;
1948         int old_is_dir, new_is_dir;
1949         int rc;
1950
1951         old_dsec = inode_security(old_dir);
1952         old_isec = backing_inode_security(old_dentry);
1953         old_is_dir = d_is_dir(old_dentry);
1954         new_dsec = inode_security(new_dir);
1955
1956         ad.type = LSM_AUDIT_DATA_DENTRY;
1957
1958         ad.u.dentry = old_dentry;
1959         rc = avc_has_perm(sid, old_dsec->sid, SECCLASS_DIR,
1960                           DIR__REMOVE_NAME | DIR__SEARCH, &ad);
1961         if (rc)
1962                 return rc;
1963         rc = avc_has_perm(sid, old_isec->sid,
1964                           old_isec->sclass, FILE__RENAME, &ad);
1965         if (rc)
1966                 return rc;
1967         if (old_is_dir && new_dir != old_dir) {
1968                 rc = avc_has_perm(sid, old_isec->sid,
1969                                   old_isec->sclass, DIR__REPARENT, &ad);
1970                 if (rc)
1971                         return rc;
1972         }
1973
1974         ad.u.dentry = new_dentry;
1975         av = DIR__ADD_NAME | DIR__SEARCH;
1976         if (d_is_positive(new_dentry))
1977                 av |= DIR__REMOVE_NAME;
1978         rc = avc_has_perm(sid, new_dsec->sid, SECCLASS_DIR, av, &ad);
1979         if (rc)
1980                 return rc;
1981         if (d_is_positive(new_dentry)) {
1982                 new_isec = backing_inode_security(new_dentry);
1983                 new_is_dir = d_is_dir(new_dentry);
1984                 rc = avc_has_perm(sid, new_isec->sid,
1985                                   new_isec->sclass,
1986                                   (new_is_dir ? DIR__RMDIR : FILE__UNLINK), &ad);
1987                 if (rc)
1988                         return rc;
1989         }
1990
1991         return 0;
1992 }
1993
1994 /* Check whether a task can perform a filesystem operation. */
1995 static int superblock_has_perm(const struct cred *cred,
1996                                struct super_block *sb,
1997                                u32 perms,
1998                                struct common_audit_data *ad)
1999 {
2000         struct superblock_security_struct *sbsec;
2001         u32 sid = cred_sid(cred);
2002
2003         sbsec = sb->s_security;
2004         return avc_has_perm(sid, sbsec->sid, SECCLASS_FILESYSTEM, perms, ad);
2005 }
2006
2007 /* Convert a Linux mode and permission mask to an access vector. */
2008 static inline u32 file_mask_to_av(int mode, int mask)
2009 {
2010         u32 av = 0;
2011
2012         if (!S_ISDIR(mode)) {
2013                 if (mask & MAY_EXEC)
2014                         av |= FILE__EXECUTE;
2015                 if (mask & MAY_READ)
2016                         av |= FILE__READ;
2017
2018                 if (mask & MAY_APPEND)
2019                         av |= FILE__APPEND;
2020                 else if (mask & MAY_WRITE)
2021                         av |= FILE__WRITE;
2022
2023         } else {
2024                 if (mask & MAY_EXEC)
2025                         av |= DIR__SEARCH;
2026                 if (mask & MAY_WRITE)
2027                         av |= DIR__WRITE;
2028                 if (mask & MAY_READ)
2029                         av |= DIR__READ;
2030         }
2031
2032         return av;
2033 }
2034
2035 /* Convert a Linux file to an access vector. */
2036 static inline u32 file_to_av(struct file *file)
2037 {
2038         u32 av = 0;
2039
2040         if (file->f_mode & FMODE_READ)
2041                 av |= FILE__READ;
2042         if (file->f_mode & FMODE_WRITE) {
2043                 if (file->f_flags & O_APPEND)
2044                         av |= FILE__APPEND;
2045                 else
2046                         av |= FILE__WRITE;
2047         }
2048         if (!av) {
2049                 /*
2050                  * Special file opened with flags 3 for ioctl-only use.
2051                  */
2052                 av = FILE__IOCTL;
2053         }
2054
2055         return av;
2056 }
2057
2058 /*
2059  * Convert a file to an access vector and include the correct open
2060  * open permission.
2061  */
2062 static inline u32 open_file_to_av(struct file *file)
2063 {
2064         u32 av = file_to_av(file);
2065
2066         if (selinux_policycap_openperm)
2067                 av |= FILE__OPEN;
2068
2069         return av;
2070 }
2071
2072 /* Hook functions begin here. */
2073
2074 static int selinux_binder_set_context_mgr(struct task_struct *mgr)
2075 {
2076         u32 mysid = current_sid();
2077         u32 mgrsid = task_sid(mgr);
2078
2079         return avc_has_perm(mysid, mgrsid, SECCLASS_BINDER,
2080                             BINDER__SET_CONTEXT_MGR, NULL);
2081 }
2082
2083 static int selinux_binder_transaction(struct task_struct *from,
2084                                       struct task_struct *to)
2085 {
2086         u32 mysid = current_sid();
2087         u32 fromsid = task_sid(from);
2088         u32 tosid = task_sid(to);
2089         int rc;
2090
2091         if (mysid != fromsid) {
2092                 rc = avc_has_perm(mysid, fromsid, SECCLASS_BINDER,
2093                                   BINDER__IMPERSONATE, NULL);
2094                 if (rc)
2095                         return rc;
2096         }
2097
2098         return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__CALL,
2099                             NULL);
2100 }
2101
2102 static int selinux_binder_transfer_binder(struct task_struct *from,
2103                                           struct task_struct *to)
2104 {
2105         u32 fromsid = task_sid(from);
2106         u32 tosid = task_sid(to);
2107
2108         return avc_has_perm(fromsid, tosid, SECCLASS_BINDER, BINDER__TRANSFER,
2109                             NULL);
2110 }
2111
2112 static int selinux_binder_transfer_file(struct task_struct *from,
2113                                         struct task_struct *to,
2114                                         struct file *file)
2115 {
2116         u32 sid = task_sid(to);
2117         struct file_security_struct *fsec = file->f_security;
2118         struct dentry *dentry = file->f_path.dentry;
2119         struct inode_security_struct *isec;
2120         struct common_audit_data ad;
2121         int rc;
2122
2123         ad.type = LSM_AUDIT_DATA_PATH;
2124         ad.u.path = file->f_path;
2125
2126         if (sid != fsec->sid) {
2127                 rc = avc_has_perm(sid, fsec->sid,
2128                                   SECCLASS_FD,
2129                                   FD__USE,
2130                                   &ad);
2131                 if (rc)
2132                         return rc;
2133         }
2134
2135         if (unlikely(IS_PRIVATE(d_backing_inode(dentry))))
2136                 return 0;
2137
2138         isec = backing_inode_security(dentry);
2139         return avc_has_perm(sid, isec->sid, isec->sclass, file_to_av(file),
2140                             &ad);
2141 }
2142
2143 static int selinux_ptrace_access_check(struct task_struct *child,
2144                                      unsigned int mode)
2145 {
2146         if (mode & PTRACE_MODE_READ) {
2147                 u32 sid = current_sid();
2148                 u32 csid = task_sid(child);
2149                 return avc_has_perm(sid, csid, SECCLASS_FILE, FILE__READ, NULL);
2150         }
2151
2152         return current_has_perm(child, PROCESS__PTRACE);
2153 }
2154
2155 static int selinux_ptrace_traceme(struct task_struct *parent)
2156 {
2157         return task_has_perm(parent, current, PROCESS__PTRACE);
2158 }
2159
2160 static int selinux_capget(struct task_struct *target, kernel_cap_t *effective,
2161                           kernel_cap_t *inheritable, kernel_cap_t *permitted)
2162 {
2163         return current_has_perm(target, PROCESS__GETCAP);
2164 }
2165
2166 static int selinux_capset(struct cred *new, const struct cred *old,
2167                           const kernel_cap_t *effective,
2168                           const kernel_cap_t *inheritable,
2169                           const kernel_cap_t *permitted)
2170 {
2171         return cred_has_perm(old, new, PROCESS__SETCAP);
2172 }
2173
2174 /*
2175  * (This comment used to live with the selinux_task_setuid hook,
2176  * which was removed).
2177  *
2178  * Since setuid only affects the current process, and since the SELinux
2179  * controls are not based on the Linux identity attributes, SELinux does not
2180  * need to control this operation.  However, SELinux does control the use of
2181  * the CAP_SETUID and CAP_SETGID capabilities using the capable hook.
2182  */
2183
2184 static int selinux_capable(const struct cred *cred, struct user_namespace *ns,
2185                            int cap, int audit)
2186 {
2187         return cred_has_capability(cred, cap, audit, ns == &init_user_ns);
2188 }
2189
2190 static int selinux_quotactl(int cmds, int type, int id, struct super_block *sb)
2191 {
2192         const struct cred *cred = current_cred();
2193         int rc = 0;
2194
2195         if (!sb)
2196                 return 0;
2197
2198         switch (cmds) {
2199         case Q_SYNC:
2200         case Q_QUOTAON:
2201         case Q_QUOTAOFF:
2202         case Q_SETINFO:
2203         case Q_SETQUOTA:
2204                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAMOD, NULL);
2205                 break;
2206         case Q_GETFMT:
2207         case Q_GETINFO:
2208         case Q_GETQUOTA:
2209                 rc = superblock_has_perm(cred, sb, FILESYSTEM__QUOTAGET, NULL);
2210                 break;
2211         default:
2212                 rc = 0;  /* let the kernel handle invalid cmds */
2213                 break;
2214         }
2215         return rc;
2216 }
2217
2218 static int selinux_quota_on(struct dentry *dentry)
2219 {
2220         const struct cred *cred = current_cred();
2221
2222         return dentry_has_perm(cred, dentry, FILE__QUOTAON);
2223 }
2224
2225 static int selinux_syslog(int type)
2226 {
2227         int rc;
2228
2229         switch (type) {
2230         case SYSLOG_ACTION_READ_ALL:    /* Read last kernel messages */
2231         case SYSLOG_ACTION_SIZE_BUFFER: /* Return size of the log buffer */
2232                 rc = task_has_system(current, SYSTEM__SYSLOG_READ);
2233                 break;
2234         case SYSLOG_ACTION_CONSOLE_OFF: /* Disable logging to console */
2235         case SYSLOG_ACTION_CONSOLE_ON:  /* Enable logging to console */
2236         /* Set level of messages printed to console */
2237         case SYSLOG_ACTION_CONSOLE_LEVEL:
2238                 rc = task_has_system(current, SYSTEM__SYSLOG_CONSOLE);
2239                 break;
2240         case SYSLOG_ACTION_CLOSE:       /* Close log */
2241         case SYSLOG_ACTION_OPEN:        /* Open log */
2242         case SYSLOG_ACTION_READ:        /* Read from log */
2243         case SYSLOG_ACTION_READ_CLEAR:  /* Read/clear last kernel messages */
2244         case SYSLOG_ACTION_CLEAR:       /* Clear ring buffer */
2245         default:
2246                 rc = task_has_system(current, SYSTEM__SYSLOG_MOD);
2247                 break;
2248         }
2249         return rc;
2250 }
2251
2252 /*
2253  * Check that a process has enough memory to allocate a new virtual
2254  * mapping. 0 means there is enough memory for the allocation to
2255  * succeed and -ENOMEM implies there is not.
2256  *
2257  * Do not audit the selinux permission check, as this is applied to all
2258  * processes that allocate mappings.
2259  */
2260 static int selinux_vm_enough_memory(struct mm_struct *mm, long pages)
2261 {
2262         int rc, cap_sys_admin = 0;
2263
2264         rc = cred_has_capability(current_cred(), CAP_SYS_ADMIN,
2265                                  SECURITY_CAP_NOAUDIT, true);
2266         if (rc == 0)
2267                 cap_sys_admin = 1;
2268
2269         return cap_sys_admin;
2270 }
2271
2272 /* binprm security operations */
2273
2274 static u32 ptrace_parent_sid(struct task_struct *task)
2275 {
2276         u32 sid = 0;
2277         struct task_struct *tracer;
2278
2279         rcu_read_lock();
2280         tracer = ptrace_parent(task);
2281         if (tracer)
2282                 sid = task_sid(tracer);
2283         rcu_read_unlock();
2284
2285         return sid;
2286 }
2287
2288 static int check_nnp_nosuid(const struct linux_binprm *bprm,
2289                             const struct task_security_struct *old_tsec,
2290                             const struct task_security_struct *new_tsec)
2291 {
2292         int nnp = (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS);
2293         int nosuid = !mnt_may_suid(bprm->file->f_path.mnt);
2294         int rc;
2295
2296         if (!nnp && !nosuid)
2297                 return 0; /* neither NNP nor nosuid */
2298
2299         if (new_tsec->sid == old_tsec->sid)
2300                 return 0; /* No change in credentials */
2301
2302         /*
2303          * The only transitions we permit under NNP or nosuid
2304          * are transitions to bounded SIDs, i.e. SIDs that are
2305          * guaranteed to only be allowed a subset of the permissions
2306          * of the current SID.
2307          */
2308         rc = security_bounded_transition(old_tsec->sid, new_tsec->sid);
2309         if (rc) {
2310                 /*
2311                  * On failure, preserve the errno values for NNP vs nosuid.
2312                  * NNP:  Operation not permitted for caller.
2313                  * nosuid:  Permission denied to file.
2314                  */
2315                 if (nnp)
2316                         return -EPERM;
2317                 else
2318                         return -EACCES;
2319         }
2320         return 0;
2321 }
2322
2323 static int selinux_bprm_set_creds(struct linux_binprm *bprm)
2324 {
2325         const struct task_security_struct *old_tsec;
2326         struct task_security_struct *new_tsec;
2327         struct inode_security_struct *isec;
2328         struct common_audit_data ad;
2329         struct inode *inode = file_inode(bprm->file);
2330         int rc;
2331
2332         /* SELinux context only depends on initial program or script and not
2333          * the script interpreter */
2334         if (bprm->cred_prepared)
2335                 return 0;
2336
2337         old_tsec = current_security();
2338         new_tsec = bprm->cred->security;
2339         isec = inode_security(inode);
2340
2341         /* Default to the current task SID. */
2342         new_tsec->sid = old_tsec->sid;
2343         new_tsec->osid = old_tsec->sid;
2344
2345         /* Reset fs, key, and sock SIDs on execve. */
2346         new_tsec->create_sid = 0;
2347         new_tsec->keycreate_sid = 0;
2348         new_tsec->sockcreate_sid = 0;
2349
2350         if (old_tsec->exec_sid) {
2351                 new_tsec->sid = old_tsec->exec_sid;
2352                 /* Reset exec SID on execve. */
2353                 new_tsec->exec_sid = 0;
2354
2355                 /* Fail on NNP or nosuid if not an allowed transition. */
2356                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2357                 if (rc)
2358                         return rc;
2359         } else {
2360                 /* Check for a default transition on this program. */
2361                 rc = security_transition_sid(old_tsec->sid, isec->sid,
2362                                              SECCLASS_PROCESS, NULL,
2363                                              &new_tsec->sid);
2364                 if (rc)
2365                         return rc;
2366
2367                 /*
2368                  * Fallback to old SID on NNP or nosuid if not an allowed
2369                  * transition.
2370                  */
2371                 rc = check_nnp_nosuid(bprm, old_tsec, new_tsec);
2372                 if (rc)
2373                         new_tsec->sid = old_tsec->sid;
2374         }
2375
2376         ad.type = LSM_AUDIT_DATA_FILE;
2377         ad.u.file = bprm->file;
2378
2379         if (new_tsec->sid == old_tsec->sid) {
2380                 rc = avc_has_perm(old_tsec->sid, isec->sid,
2381                                   SECCLASS_FILE, FILE__EXECUTE_NO_TRANS, &ad);
2382                 if (rc)
2383                         return rc;
2384         } else {
2385                 /* Check permissions for the transition. */
2386                 rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2387                                   SECCLASS_PROCESS, PROCESS__TRANSITION, &ad);
2388                 if (rc)
2389                         return rc;
2390
2391                 rc = avc_has_perm(new_tsec->sid, isec->sid,
2392                                   SECCLASS_FILE, FILE__ENTRYPOINT, &ad);
2393                 if (rc)
2394                         return rc;
2395
2396                 /* Check for shared state */
2397                 if (bprm->unsafe & LSM_UNSAFE_SHARE) {
2398                         rc = avc_has_perm(old_tsec->sid, new_tsec->sid,
2399                                           SECCLASS_PROCESS, PROCESS__SHARE,
2400                                           NULL);
2401                         if (rc)
2402                                 return -EPERM;
2403                 }
2404
2405                 /* Make sure that anyone attempting to ptrace over a task that
2406                  * changes its SID has the appropriate permit */
2407                 if (bprm->unsafe &
2408                     (LSM_UNSAFE_PTRACE | LSM_UNSAFE_PTRACE_CAP)) {
2409                         u32 ptsid = ptrace_parent_sid(current);
2410                         if (ptsid != 0) {
2411                                 rc = avc_has_perm(ptsid, new_tsec->sid,
2412                                                   SECCLASS_PROCESS,
2413                                                   PROCESS__PTRACE, NULL);
2414                                 if (rc)
2415                                         return -EPERM;
2416                         }
2417                 }
2418
2419                 /* Clear any possibly unsafe personality bits on exec: */
2420                 bprm->per_clear |= PER_CLEAR_ON_SETID;
2421         }
2422
2423         return 0;
2424 }
2425
2426 static int selinux_bprm_secureexec(struct linux_binprm *bprm)
2427 {
2428         const struct task_security_struct *tsec = current_security();
2429         u32 sid, osid;
2430         int atsecure = 0;
2431
2432         sid = tsec->sid;
2433         osid = tsec->osid;
2434
2435         if (osid != sid) {
2436                 /* Enable secure mode for SIDs transitions unless
2437                    the noatsecure permission is granted between
2438                    the two SIDs, i.e. ahp returns 0. */
2439                 atsecure = avc_has_perm(osid, sid,
2440                                         SECCLASS_PROCESS,
2441                                         PROCESS__NOATSECURE, NULL);
2442         }
2443
2444         return !!atsecure;
2445 }
2446
2447 static int match_file(const void *p, struct file *file, unsigned fd)
2448 {
2449         return file_has_perm(p, file, file_to_av(file)) ? fd + 1 : 0;
2450 }
2451
2452 /* Derived from fs/exec.c:flush_old_files. */
2453 static inline void flush_unauthorized_files(const struct cred *cred,
2454                                             struct files_struct *files)
2455 {
2456         struct file *file, *devnull = NULL;
2457         struct tty_struct *tty;
2458         int drop_tty = 0;
2459         unsigned n;
2460
2461         tty = get_current_tty();
2462         if (tty) {
2463                 spin_lock(&tty->files_lock);
2464                 if (!list_empty(&tty->tty_files)) {
2465                         struct tty_file_private *file_priv;
2466
2467                         /* Revalidate access to controlling tty.
2468                            Use file_path_has_perm on the tty path directly
2469                            rather than using file_has_perm, as this particular
2470                            open file may belong to another process and we are
2471                            only interested in the inode-based check here. */
2472                         file_priv = list_first_entry(&tty->tty_files,
2473                                                 struct tty_file_private, list);
2474                         file = file_priv->file;
2475                         if (file_path_has_perm(cred, file, FILE__READ | FILE__WRITE))
2476                                 drop_tty = 1;
2477                 }
2478                 spin_unlock(&tty->files_lock);
2479                 tty_kref_put(tty);
2480         }
2481         /* Reset controlling tty. */
2482         if (drop_tty)
2483                 no_tty();
2484
2485         /* Revalidate access to inherited open files. */
2486         n = iterate_fd(files, 0, match_file, cred);
2487         if (!n) /* none found? */
2488                 return;
2489
2490         devnull = dentry_open(&selinux_null, O_RDWR, cred);
2491         if (IS_ERR(devnull))
2492                 devnull = NULL;
2493         /* replace all the matching ones with this */
2494         do {
2495                 replace_fd(n - 1, devnull, 0);
2496         } while ((n = iterate_fd(files, n, match_file, cred)) != 0);
2497         if (devnull)
2498                 fput(devnull);
2499 }
2500
2501 /*
2502  * Prepare a process for imminent new credential changes due to exec
2503  */
2504 static void selinux_bprm_committing_creds(struct linux_binprm *bprm)
2505 {
2506         struct task_security_struct *new_tsec;
2507         struct rlimit *rlim, *initrlim;
2508         int rc, i;
2509
2510         new_tsec = bprm->cred->security;
2511         if (new_tsec->sid == new_tsec->osid)
2512                 return;
2513
2514         /* Close files for which the new task SID is not authorized. */
2515         flush_unauthorized_files(bprm->cred, current->files);
2516
2517         /* Always clear parent death signal on SID transitions. */
2518         current->pdeath_signal = 0;
2519
2520         /* Check whether the new SID can inherit resource limits from the old
2521          * SID.  If not, reset all soft limits to the lower of the current
2522          * task's hard limit and the init task's soft limit.
2523          *
2524          * Note that the setting of hard limits (even to lower them) can be
2525          * controlled by the setrlimit check.  The inclusion of the init task's
2526          * soft limit into the computation is to avoid resetting soft limits
2527          * higher than the default soft limit for cases where the default is
2528          * lower than the hard limit, e.g. RLIMIT_CORE or RLIMIT_STACK.
2529          */
2530         rc = avc_has_perm(new_tsec->osid, new_tsec->sid, SECCLASS_PROCESS,
2531                           PROCESS__RLIMITINH, NULL);
2532         if (rc) {
2533                 /* protect against do_prlimit() */
2534                 task_lock(current);
2535                 for (i = 0; i < RLIM_NLIMITS; i++) {
2536                         rlim = current->signal->rlim + i;
2537                         initrlim = init_task.signal->rlim + i;
2538                         rlim->rlim_cur = min(rlim->rlim_max, initrlim->rlim_cur);
2539                 }
2540                 task_unlock(current);
2541                 if (IS_ENABLED(CONFIG_POSIX_TIMERS))
2542                         update_rlimit_cpu(current, rlimit(RLIMIT_CPU));
2543         }
2544 }
2545
2546 /*
2547  * Clean up the process immediately after the installation of new credentials
2548  * due to exec
2549  */
2550 static void selinux_bprm_committed_creds(struct linux_binprm *bprm)
2551 {
2552         const struct task_security_struct *tsec = current_security();
2553         struct itimerval itimer;
2554         u32 osid, sid;
2555         int rc, i;
2556
2557         osid = tsec->osid;
2558         sid = tsec->sid;
2559
2560         if (sid == osid)
2561                 return;
2562
2563         /* Check whether the new SID can inherit signal state from the old SID.
2564          * If not, clear itimers to avoid subsequent signal generation and
2565          * flush and unblock signals.
2566          *
2567          * This must occur _after_ the task SID has been updated so that any
2568          * kill done after the flush will be checked against the new SID.
2569          */
2570         rc = avc_has_perm(osid, sid, SECCLASS_PROCESS, PROCESS__SIGINH, NULL);
2571         if (rc) {
2572                 if (IS_ENABLED(CONFIG_POSIX_TIMERS)) {
2573                         memset(&itimer, 0, sizeof itimer);
2574                         for (i = 0; i < 3; i++)
2575                                 do_setitimer(i, &itimer, NULL);
2576                 }
2577                 spin_lock_irq(&current->sighand->siglock);
2578                 if (!fatal_signal_pending(current)) {
2579                         flush_sigqueue(&current->pending);
2580                         flush_sigqueue(&current->signal->shared_pending);
2581                         flush_signal_handlers(current, 1);
2582                         sigemptyset(&current->blocked);
2583                         recalc_sigpending();
2584                 }
2585                 spin_unlock_irq(&current->sighand->siglock);
2586         }
2587
2588         /* Wake up the parent if it is waiting so that it can recheck
2589          * wait permission to the new task SID. */
2590         read_lock(&tasklist_lock);
2591         __wake_up_parent(current, current->real_parent);
2592         read_unlock(&tasklist_lock);
2593 }
2594
2595 /* superblock security operations */
2596
2597 static int selinux_sb_alloc_security(struct super_block *sb)
2598 {
2599         return superblock_alloc_security(sb);
2600 }
2601
2602 static void selinux_sb_free_security(struct super_block *sb)
2603 {
2604         superblock_free_security(sb);
2605 }
2606
2607 static inline int match_prefix(char *prefix, int plen, char *option, int olen)
2608 {
2609         if (plen > olen)
2610                 return 0;
2611
2612         return !memcmp(prefix, option, plen);
2613 }
2614
2615 static inline int selinux_option(char *option, int len)
2616 {
2617         return (match_prefix(CONTEXT_STR, sizeof(CONTEXT_STR)-1, option, len) ||
2618                 match_prefix(FSCONTEXT_STR, sizeof(FSCONTEXT_STR)-1, option, len) ||
2619                 match_prefix(DEFCONTEXT_STR, sizeof(DEFCONTEXT_STR)-1, option, len) ||
2620                 match_prefix(ROOTCONTEXT_STR, sizeof(ROOTCONTEXT_STR)-1, option, len) ||
2621                 match_prefix(LABELSUPP_STR, sizeof(LABELSUPP_STR)-1, option, len));
2622 }
2623
2624 static inline void take_option(char **to, char *from, int *first, int len)
2625 {
2626         if (!*first) {
2627                 **to = ',';
2628                 *to += 1;
2629         } else
2630                 *first = 0;
2631         memcpy(*to, from, len);
2632         *to += len;
2633 }
2634
2635 static inline void take_selinux_option(char **to, char *from, int *first,
2636                                        int len)
2637 {
2638         int current_size = 0;
2639
2640         if (!*first) {
2641                 **to = '|';
2642                 *to += 1;
2643         } else
2644                 *first = 0;
2645
2646         while (current_size < len) {
2647                 if (*from != '"') {
2648                         **to = *from;
2649                         *to += 1;
2650                 }
2651                 from += 1;
2652                 current_size += 1;
2653         }
2654 }
2655
2656 static int selinux_sb_copy_data(char *orig, char *copy)
2657 {
2658         int fnosec, fsec, rc = 0;
2659         char *in_save, *in_curr, *in_end;
2660         char *sec_curr, *nosec_save, *nosec;
2661         int open_quote = 0;
2662
2663         in_curr = orig;
2664         sec_curr = copy;
2665
2666         nosec = (char *)get_zeroed_page(GFP_KERNEL);
2667         if (!nosec) {
2668                 rc = -ENOMEM;
2669                 goto out;
2670         }
2671
2672         nosec_save = nosec;
2673         fnosec = fsec = 1;
2674         in_save = in_end = orig;
2675
2676         do {
2677                 if (*in_end == '"')
2678                         open_quote = !open_quote;
2679                 if ((*in_end == ',' && open_quote == 0) ||
2680                                 *in_end == '\0') {
2681                         int len = in_end - in_curr;
2682
2683                         if (selinux_option(in_curr, len))
2684                                 take_selinux_option(&sec_curr, in_curr, &fsec, len);
2685                         else
2686                                 take_option(&nosec, in_curr, &fnosec, len);
2687
2688                         in_curr = in_end + 1;
2689                 }
2690         } while (*in_end++);
2691
2692         strcpy(in_save, nosec_save);
2693         free_page((unsigned long)nosec_save);
2694 out:
2695         return rc;
2696 }
2697
2698 static int selinux_sb_remount(struct super_block *sb, void *data)
2699 {
2700         int rc, i, *flags;
2701         struct security_mnt_opts opts;
2702         char *secdata, **mount_options;
2703         struct superblock_security_struct *sbsec = sb->s_security;
2704
2705         if (!(sbsec->flags & SE_SBINITIALIZED))
2706                 return 0;
2707
2708         if (!data)
2709                 return 0;
2710
2711         if (sb->s_type->fs_flags & FS_BINARY_MOUNTDATA)
2712                 return 0;
2713
2714         security_init_mnt_opts(&opts);
2715         secdata = alloc_secdata();
2716         if (!secdata)
2717                 return -ENOMEM;
2718         rc = selinux_sb_copy_data(data, secdata);
2719         if (rc)
2720                 goto out_free_secdata;
2721
2722         rc = selinux_parse_opts_str(secdata, &opts);
2723         if (rc)
2724                 goto out_free_secdata;
2725
2726         mount_options = opts.mnt_opts;
2727         flags = opts.mnt_opts_flags;
2728
2729         for (i = 0; i < opts.num_mnt_opts; i++) {
2730                 u32 sid;
2731
2732                 if (flags[i] == SBLABEL_MNT)
2733                         continue;
2734                 rc = security_context_str_to_sid(mount_options[i], &sid, GFP_KERNEL);
2735                 if (rc) {
2736                         printk(KERN_WARNING "SELinux: security_context_str_to_sid"
2737                                "(%s) failed for (dev %s, type %s) errno=%d\n",
2738                                mount_options[i], sb->s_id, sb->s_type->name, rc);
2739                         goto out_free_opts;
2740                 }
2741                 rc = -EINVAL;
2742                 switch (flags[i]) {
2743                 case FSCONTEXT_MNT:
2744                         if (bad_option(sbsec, FSCONTEXT_MNT, sbsec->sid, sid))
2745                                 goto out_bad_option;
2746                         break;
2747                 case CONTEXT_MNT:
2748                         if (bad_option(sbsec, CONTEXT_MNT, sbsec->mntpoint_sid, sid))
2749                                 goto out_bad_option;
2750                         break;
2751                 case ROOTCONTEXT_MNT: {
2752                         struct inode_security_struct *root_isec;
2753                         root_isec = backing_inode_security(sb->s_root);
2754
2755                         if (bad_option(sbsec, ROOTCONTEXT_MNT, root_isec->sid, sid))
2756                                 goto out_bad_option;
2757                         break;
2758                 }
2759                 case DEFCONTEXT_MNT:
2760                         if (bad_option(sbsec, DEFCONTEXT_MNT, sbsec->def_sid, sid))
2761                                 goto out_bad_option;
2762                         break;
2763                 default:
2764                         goto out_free_opts;
2765                 }
2766         }
2767
2768         rc = 0;
2769 out_free_opts:
2770         security_free_mnt_opts(&opts);
2771 out_free_secdata:
2772         free_secdata(secdata);
2773         return rc;
2774 out_bad_option:
2775         printk(KERN_WARNING "SELinux: unable to change security options "
2776                "during remount (dev %s, type=%s)\n", sb->s_id,
2777                sb->s_type->name);
2778         goto out_free_opts;
2779 }
2780
2781 static int selinux_sb_kern_mount(struct super_block *sb, int flags, void *data)
2782 {
2783         const struct cred *cred = current_cred();
2784         struct common_audit_data ad;
2785         int rc;
2786
2787         rc = superblock_doinit(sb, data);
2788         if (rc)
2789                 return rc;
2790
2791         /* Allow all mounts performed by the kernel */
2792         if (flags & MS_KERNMOUNT)
2793                 return 0;
2794
2795         ad.type = LSM_AUDIT_DATA_DENTRY;
2796         ad.u.dentry = sb->s_root;
2797         return superblock_has_perm(cred, sb, FILESYSTEM__MOUNT, &ad);
2798 }
2799
2800 static int selinux_sb_statfs(struct dentry *dentry)
2801 {
2802         const struct cred *cred = current_cred();
2803         struct common_audit_data ad;
2804
2805         ad.type = LSM_AUDIT_DATA_DENTRY;
2806         ad.u.dentry = dentry->d_sb->s_root;
2807         return superblock_has_perm(cred, dentry->d_sb, FILESYSTEM__GETATTR, &ad);
2808 }
2809
2810 static int selinux_mount(const char *dev_name,
2811                          const struct path *path,
2812                          const char *type,
2813                          unsigned long flags,
2814                          void *data)
2815 {
2816         const struct cred *cred = current_cred();
2817
2818         if (flags & MS_REMOUNT)
2819                 return superblock_has_perm(cred, path->dentry->d_sb,
2820                                            FILESYSTEM__REMOUNT, NULL);
2821         else
2822                 return path_has_perm(cred, path, FILE__MOUNTON);
2823 }
2824
2825 static int selinux_umount(struct vfsmount *mnt, int flags)
2826 {
2827         const struct cred *cred = current_cred();
2828
2829         return superblock_has_perm(cred, mnt->mnt_sb,
2830                                    FILESYSTEM__UNMOUNT, NULL);
2831 }
2832
2833 /* inode security operations */
2834
2835 static int selinux_inode_alloc_security(struct inode *inode)
2836 {
2837         return inode_alloc_security(inode);
2838 }
2839
2840 static void selinux_inode_free_security(struct inode *inode)
2841 {
2842         inode_free_security(inode);
2843 }
2844
2845 static int selinux_dentry_init_security(struct dentry *dentry, int mode,
2846                                         const struct qstr *name, void **ctx,
2847                                         u32 *ctxlen)
2848 {
2849         u32 newsid;
2850         int rc;
2851
2852         rc = selinux_determine_inode_label(current_security(),
2853                                            d_inode(dentry->d_parent), name,
2854                                            inode_mode_to_security_class(mode),
2855                                            &newsid);
2856         if (rc)
2857                 return rc;
2858
2859         return security_sid_to_context(newsid, (char **)ctx, ctxlen);
2860 }
2861
2862 static int selinux_dentry_create_files_as(struct dentry *dentry, int mode,
2863                                           struct qstr *name,
2864                                           const struct cred *old,
2865                                           struct cred *new)
2866 {
2867         u32 newsid;
2868         int rc;
2869         struct task_security_struct *tsec;
2870
2871         rc = selinux_determine_inode_label(old->security,
2872                                            d_inode(dentry->d_parent), name,
2873                                            inode_mode_to_security_class(mode),
2874                                            &newsid);
2875         if (rc)
2876                 return rc;
2877
2878         tsec = new->security;
2879         tsec->create_sid = newsid;
2880         return 0;
2881 }
2882
2883 static int selinux_inode_init_security(struct inode *inode, struct inode *dir,
2884                                        const struct qstr *qstr,
2885                                        const char **name,
2886                                        void **value, size_t *len)
2887 {
2888         const struct task_security_struct *tsec = current_security();
2889         struct superblock_security_struct *sbsec;
2890         u32 sid, newsid, clen;
2891         int rc;
2892         char *context;
2893
2894         sbsec = dir->i_sb->s_security;
2895
2896         sid = tsec->sid;
2897         newsid = tsec->create_sid;
2898
2899         rc = selinux_determine_inode_label(current_security(),
2900                 dir, qstr,
2901                 inode_mode_to_security_class(inode->i_mode),
2902                 &newsid);
2903         if (rc)
2904                 return rc;
2905
2906         /* Possibly defer initialization to selinux_complete_init. */
2907         if (sbsec->flags & SE_SBINITIALIZED) {
2908                 struct inode_security_struct *isec = inode->i_security;
2909                 isec->sclass = inode_mode_to_security_class(inode->i_mode);
2910                 isec->sid = newsid;
2911                 isec->initialized = LABEL_INITIALIZED;
2912         }
2913
2914         if (!ss_initialized || !(sbsec->flags & SBLABEL_MNT))
2915                 return -EOPNOTSUPP;
2916
2917         if (name)
2918                 *name = XATTR_SELINUX_SUFFIX;
2919
2920         if (value && len) {
2921                 rc = security_sid_to_context_force(newsid, &context, &clen);
2922                 if (rc)
2923                         return rc;
2924                 *value = context;
2925                 *len = clen;
2926         }
2927
2928         return 0;
2929 }
2930
2931 static int selinux_inode_create(struct inode *dir, struct dentry *dentry, umode_t mode)
2932 {
2933         return may_create(dir, dentry, SECCLASS_FILE);
2934 }
2935
2936 static int selinux_inode_link(struct dentry *old_dentry, struct inode *dir, struct dentry *new_dentry)
2937 {
2938         return may_link(dir, old_dentry, MAY_LINK);
2939 }
2940
2941 static int selinux_inode_unlink(struct inode *dir, struct dentry *dentry)
2942 {
2943         return may_link(dir, dentry, MAY_UNLINK);
2944 }
2945
2946 static int selinux_inode_symlink(struct inode *dir, struct dentry *dentry, const char *name)
2947 {
2948         return may_create(dir, dentry, SECCLASS_LNK_FILE);
2949 }
2950
2951 static int selinux_inode_mkdir(struct inode *dir, struct dentry *dentry, umode_t mask)
2952 {
2953         return may_create(dir, dentry, SECCLASS_DIR);
2954 }
2955
2956 static int selinux_inode_rmdir(struct inode *dir, struct dentry *dentry)
2957 {
2958         return may_link(dir, dentry, MAY_RMDIR);
2959 }
2960
2961 static int selinux_inode_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t dev)
2962 {
2963         return may_create(dir, dentry, inode_mode_to_security_class(mode));
2964 }
2965
2966 static int selinux_inode_rename(struct inode *old_inode, struct dentry *old_dentry,
2967                                 struct inode *new_inode, struct dentry *new_dentry)
2968 {
2969         return may_rename(old_inode, old_dentry, new_inode, new_dentry);
2970 }
2971
2972 static int selinux_inode_readlink(struct dentry *dentry)
2973 {
2974         const struct cred *cred = current_cred();
2975
2976         return dentry_has_perm(cred, dentry, FILE__READ);
2977 }
2978
2979 static int selinux_inode_follow_link(struct dentry *dentry, struct inode *inode,
2980                                      bool rcu)
2981 {
2982         const struct cred *cred = current_cred();
2983         struct common_audit_data ad;
2984         struct inode_security_struct *isec;
2985         u32 sid;
2986
2987         validate_creds(cred);
2988
2989         ad.type = LSM_AUDIT_DATA_DENTRY;
2990         ad.u.dentry = dentry;
2991         sid = cred_sid(cred);
2992         isec = inode_security_rcu(inode, rcu);
2993         if (IS_ERR(isec))
2994                 return PTR_ERR(isec);
2995
2996         return avc_has_perm_flags(sid, isec->sid, isec->sclass, FILE__READ, &ad,
2997                                   rcu ? MAY_NOT_BLOCK : 0);
2998 }
2999
3000 static noinline int audit_inode_permission(struct inode *inode,
3001                                            u32 perms, u32 audited, u32 denied,
3002                                            int result,
3003                                            unsigned flags)
3004 {
3005         struct common_audit_data ad;
3006         struct inode_security_struct *isec = inode->i_security;
3007         int rc;
3008
3009         ad.type = LSM_AUDIT_DATA_INODE;
3010         ad.u.inode = inode;
3011
3012         rc = slow_avc_audit(current_sid(), isec->sid, isec->sclass, perms,
3013                             audited, denied, result, &ad, flags);
3014         if (rc)
3015                 return rc;
3016         return 0;
3017 }
3018
3019 static int selinux_inode_permission(struct inode *inode, int mask)
3020 {
3021         const struct cred *cred = current_cred();
3022         u32 perms;
3023         bool from_access;
3024         unsigned flags = mask & MAY_NOT_BLOCK;
3025         struct inode_security_struct *isec;
3026         u32 sid;
3027         struct av_decision avd;
3028         int rc, rc2;
3029         u32 audited, denied;
3030
3031         from_access = mask & MAY_ACCESS;
3032         mask &= (MAY_READ|MAY_WRITE|MAY_EXEC|MAY_APPEND);
3033
3034         /* No permission to check.  Existence test. */
3035         if (!mask)
3036                 return 0;
3037
3038         validate_creds(cred);
3039
3040         if (unlikely(IS_PRIVATE(inode)))
3041                 return 0;
3042
3043         perms = file_mask_to_av(inode->i_mode, mask);
3044
3045         sid = cred_sid(cred);
3046         isec = inode_security_rcu(inode, flags & MAY_NOT_BLOCK);
3047         if (IS_ERR(isec))
3048                 return PTR_ERR(isec);
3049
3050         rc = avc_has_perm_noaudit(sid, isec->sid, isec->sclass, perms, 0, &avd);
3051         audited = avc_audit_required(perms, &avd, rc,
3052                                      from_access ? FILE__AUDIT_ACCESS : 0,
3053                                      &denied);
3054         if (likely(!audited))
3055                 return rc;
3056
3057         rc2 = audit_inode_permission(inode, perms, audited, denied, rc, flags);
3058         if (rc2)
3059                 return rc2;
3060         return rc;
3061 }
3062
3063 static int selinux_inode_setattr(struct dentry *dentry, struct iattr *iattr)
3064 {
3065         const struct cred *cred = current_cred();
3066         unsigned int ia_valid = iattr->ia_valid;
3067         __u32 av = FILE__WRITE;
3068
3069         /* ATTR_FORCE is just used for ATTR_KILL_S[UG]ID. */
3070         if (ia_valid & ATTR_FORCE) {
3071                 ia_valid &= ~(ATTR_KILL_SUID | ATTR_KILL_SGID | ATTR_MODE |
3072                               ATTR_FORCE);
3073                 if (!ia_valid)
3074                         return 0;
3075         }
3076
3077         if (ia_valid & (ATTR_MODE | ATTR_UID | ATTR_GID |
3078                         ATTR_ATIME_SET | ATTR_MTIME_SET | ATTR_TIMES_SET))
3079                 return dentry_has_perm(cred, dentry, FILE__SETATTR);
3080
3081         if (selinux_policycap_openperm && (ia_valid & ATTR_SIZE)
3082                         && !(ia_valid & ATTR_FILE))
3083                 av |= FILE__OPEN;
3084
3085         return dentry_has_perm(cred, dentry, av);
3086 }
3087
3088 static int selinux_inode_getattr(const struct path *path)
3089 {
3090         return path_has_perm(current_cred(), path, FILE__GETATTR);
3091 }
3092
3093 static int selinux_inode_setotherxattr(struct dentry *dentry, const char *name)
3094 {
3095         const struct cred *cred = current_cred();
3096
3097         if (!strncmp(name, XATTR_SECURITY_PREFIX,
3098                      sizeof XATTR_SECURITY_PREFIX - 1)) {
3099                 if (!strcmp(name, XATTR_NAME_CAPS)) {
3100                         if (!capable(CAP_SETFCAP))
3101                                 return -EPERM;
3102                 } else if (!capable(CAP_SYS_ADMIN)) {
3103                         /* A different attribute in the security namespace.
3104                            Restrict to administrator. */
3105                         return -EPERM;
3106                 }
3107         }
3108
3109         /* Not an attribute we recognize, so just check the
3110            ordinary setattr permission. */
3111         return dentry_has_perm(cred, dentry, FILE__SETATTR);
3112 }
3113
3114 static int selinux_inode_setxattr(struct dentry *dentry, const char *name,
3115                                   const void *value, size_t size, int flags)
3116 {
3117         struct inode *inode = d_backing_inode(dentry);
3118         struct inode_security_struct *isec;
3119         struct superblock_security_struct *sbsec;
3120         struct common_audit_data ad;
3121         u32 newsid, sid = current_sid();
3122         int rc = 0;
3123
3124         if (strcmp(name, XATTR_NAME_SELINUX))
3125                 return selinux_inode_setotherxattr(dentry, name);
3126
3127         sbsec = inode->i_sb->s_security;
3128         if (!(sbsec->flags & SBLABEL_MNT))
3129                 return -EOPNOTSUPP;
3130
3131         if (!inode_owner_or_capable(inode))
3132                 return -EPERM;
3133
3134         ad.type = LSM_AUDIT_DATA_DENTRY;
3135         ad.u.dentry = dentry;
3136
3137         isec = backing_inode_security(dentry);
3138         rc = avc_has_perm(sid, isec->sid, isec->sclass,
3139                           FILE__RELABELFROM, &ad);
3140         if (rc)
3141                 return rc;
3142
3143         rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
3144         if (rc == -EINVAL) {
3145                 if (!capable(CAP_MAC_ADMIN)) {
3146                         struct audit_buffer *ab;
3147                         size_t audit_size;
3148                         const char *str;
3149
3150                         /* We strip a nul only if it is at the end, otherwise the
3151                          * context contains a nul and we should audit that */
3152                         if (value) {
3153                                 str = value;
3154                                 if (str[size - 1] == '\0')
3155                                         audit_size = size - 1;
3156                                 else
3157                                         audit_size = size;
3158                         } else {
3159                                 str = "";
3160                                 audit_size = 0;
3161                         }
3162                         ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
3163                         audit_log_format(ab, "op=setxattr invalid_context=");
3164                         audit_log_n_untrustedstring(ab, value, audit_size);
3165                         audit_log_end(ab);
3166
3167                         return rc;
3168                 }
3169                 rc = security_context_to_sid_force(value, size, &newsid);
3170         }
3171         if (rc)
3172                 return rc;
3173
3174         rc = avc_has_perm(sid, newsid, isec->sclass,
3175                           FILE__RELABELTO, &ad);
3176         if (rc)
3177                 return rc;
3178
3179         rc = security_validate_transition(isec->sid, newsid, sid,
3180                                           isec->sclass);
3181         if (rc)
3182                 return rc;
3183
3184         return avc_has_perm(newsid,
3185                             sbsec->sid,
3186                             SECCLASS_FILESYSTEM,
3187                             FILESYSTEM__ASSOCIATE,
3188                             &ad);
3189 }
3190
3191 static void selinux_inode_post_setxattr(struct dentry *dentry, const char *name,
3192                                         const void *value, size_t size,
3193                                         int flags)
3194 {
3195         struct inode *inode = d_backing_inode(dentry);
3196         struct inode_security_struct *isec;
3197         u32 newsid;
3198         int rc;
3199
3200         if (strcmp(name, XATTR_NAME_SELINUX)) {
3201                 /* Not an attribute we recognize, so nothing to do. */
3202                 return;
3203         }
3204
3205         rc = security_context_to_sid_force(value, size, &newsid);
3206         if (rc) {
3207                 printk(KERN_ERR "SELinux:  unable to map context to SID"
3208                        "for (%s, %lu), rc=%d\n",
3209                        inode->i_sb->s_id, inode->i_ino, -rc);
3210                 return;
3211         }
3212
3213         isec = backing_inode_security(dentry);
3214         spin_lock(&isec->lock);
3215         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3216         isec->sid = newsid;
3217         isec->initialized = LABEL_INITIALIZED;
3218         spin_unlock(&isec->lock);
3219
3220         return;
3221 }
3222
3223 static int selinux_inode_getxattr(struct dentry *dentry, const char *name)
3224 {
3225         const struct cred *cred = current_cred();
3226
3227         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3228 }
3229
3230 static int selinux_inode_listxattr(struct dentry *dentry)
3231 {
3232         const struct cred *cred = current_cred();
3233
3234         return dentry_has_perm(cred, dentry, FILE__GETATTR);
3235 }
3236
3237 static int selinux_inode_removexattr(struct dentry *dentry, const char *name)
3238 {
3239         if (strcmp(name, XATTR_NAME_SELINUX))
3240                 return selinux_inode_setotherxattr(dentry, name);
3241
3242         /* No one is allowed to remove a SELinux security label.
3243            You can change the label, but all data must be labeled. */
3244         return -EACCES;
3245 }
3246
3247 /*
3248  * Copy the inode security context value to the user.
3249  *
3250  * Permission check is handled by selinux_inode_getxattr hook.
3251  */
3252 static int selinux_inode_getsecurity(struct inode *inode, const char *name, void **buffer, bool alloc)
3253 {
3254         u32 size;
3255         int error;
3256         char *context = NULL;
3257         struct inode_security_struct *isec;
3258
3259         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3260                 return -EOPNOTSUPP;
3261
3262         /*
3263          * If the caller has CAP_MAC_ADMIN, then get the raw context
3264          * value even if it is not defined by current policy; otherwise,
3265          * use the in-core value under current policy.
3266          * Use the non-auditing forms of the permission checks since
3267          * getxattr may be called by unprivileged processes commonly
3268          * and lack of permission just means that we fall back to the
3269          * in-core context value, not a denial.
3270          */
3271         error = cap_capable(current_cred(), &init_user_ns, CAP_MAC_ADMIN,
3272                             SECURITY_CAP_NOAUDIT);
3273         if (!error)
3274                 error = cred_has_capability(current_cred(), CAP_MAC_ADMIN,
3275                                             SECURITY_CAP_NOAUDIT, true);
3276         isec = inode_security(inode);
3277         if (!error)
3278                 error = security_sid_to_context_force(isec->sid, &context,
3279                                                       &size);
3280         else
3281                 error = security_sid_to_context(isec->sid, &context, &size);
3282         if (error)
3283                 return error;
3284         error = size;
3285         if (alloc) {
3286                 *buffer = context;
3287                 goto out_nofree;
3288         }
3289         kfree(context);
3290 out_nofree:
3291         return error;
3292 }
3293
3294 static int selinux_inode_setsecurity(struct inode *inode, const char *name,
3295                                      const void *value, size_t size, int flags)
3296 {
3297         struct inode_security_struct *isec = inode_security_novalidate(inode);
3298         u32 newsid;
3299         int rc;
3300
3301         if (strcmp(name, XATTR_SELINUX_SUFFIX))
3302                 return -EOPNOTSUPP;
3303
3304         if (!value || !size)
3305                 return -EACCES;
3306
3307         rc = security_context_to_sid(value, size, &newsid, GFP_KERNEL);
3308         if (rc)
3309                 return rc;
3310
3311         spin_lock(&isec->lock);
3312         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3313         isec->sid = newsid;
3314         isec->initialized = LABEL_INITIALIZED;
3315         spin_unlock(&isec->lock);
3316         return 0;
3317 }
3318
3319 static int selinux_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer_size)
3320 {
3321         const int len = sizeof(XATTR_NAME_SELINUX);
3322         if (buffer && len <= buffer_size)
3323                 memcpy(buffer, XATTR_NAME_SELINUX, len);
3324         return len;
3325 }
3326
3327 static void selinux_inode_getsecid(struct inode *inode, u32 *secid)
3328 {
3329         struct inode_security_struct *isec = inode_security_novalidate(inode);
3330         *secid = isec->sid;
3331 }
3332
3333 static int selinux_inode_copy_up(struct dentry *src, struct cred **new)
3334 {
3335         u32 sid;
3336         struct task_security_struct *tsec;
3337         struct cred *new_creds = *new;
3338
3339         if (new_creds == NULL) {
3340                 new_creds = prepare_creds();
3341                 if (!new_creds)
3342                         return -ENOMEM;
3343         }
3344
3345         tsec = new_creds->security;
3346         /* Get label from overlay inode and set it in create_sid */
3347         selinux_inode_getsecid(d_inode(src), &sid);
3348         tsec->create_sid = sid;
3349         *new = new_creds;
3350         return 0;
3351 }
3352
3353 static int selinux_inode_copy_up_xattr(const char *name)
3354 {
3355         /* The copy_up hook above sets the initial context on an inode, but we
3356          * don't then want to overwrite it by blindly copying all the lower
3357          * xattrs up.  Instead, we have to filter out SELinux-related xattrs.
3358          */
3359         if (strcmp(name, XATTR_NAME_SELINUX) == 0)
3360                 return 1; /* Discard */
3361         /*
3362          * Any other attribute apart from SELINUX is not claimed, supported
3363          * by selinux.
3364          */
3365         return -EOPNOTSUPP;
3366 }
3367
3368 /* file security operations */
3369
3370 static int selinux_revalidate_file_permission(struct file *file, int mask)
3371 {
3372         const struct cred *cred = current_cred();
3373         struct inode *inode = file_inode(file);
3374
3375         /* file_mask_to_av won't add FILE__WRITE if MAY_APPEND is set */
3376         if ((file->f_flags & O_APPEND) && (mask & MAY_WRITE))
3377                 mask |= MAY_APPEND;
3378
3379         return file_has_perm(cred, file,
3380                              file_mask_to_av(inode->i_mode, mask));
3381 }
3382
3383 static int selinux_file_permission(struct file *file, int mask)
3384 {
3385         struct inode *inode = file_inode(file);
3386         struct file_security_struct *fsec = file->f_security;
3387         struct inode_security_struct *isec;
3388         u32 sid = current_sid();
3389
3390         if (!mask)
3391                 /* No permission to check.  Existence test. */
3392                 return 0;
3393
3394         isec = inode_security(inode);
3395         if (sid == fsec->sid && fsec->isid == isec->sid &&
3396             fsec->pseqno == avc_policy_seqno())
3397                 /* No change since file_open check. */
3398                 return 0;
3399
3400         return selinux_revalidate_file_permission(file, mask);
3401 }
3402
3403 static int selinux_file_alloc_security(struct file *file)
3404 {
3405         return file_alloc_security(file);
3406 }
3407
3408 static void selinux_file_free_security(struct file *file)
3409 {
3410         file_free_security(file);
3411 }
3412
3413 /*
3414  * Check whether a task has the ioctl permission and cmd
3415  * operation to an inode.
3416  */
3417 static int ioctl_has_perm(const struct cred *cred, struct file *file,
3418                 u32 requested, u16 cmd)
3419 {
3420         struct common_audit_data ad;
3421         struct file_security_struct *fsec = file->f_security;
3422         struct inode *inode = file_inode(file);
3423         struct inode_security_struct *isec;
3424         struct lsm_ioctlop_audit ioctl;
3425         u32 ssid = cred_sid(cred);
3426         int rc;
3427         u8 driver = cmd >> 8;
3428         u8 xperm = cmd & 0xff;
3429
3430         ad.type = LSM_AUDIT_DATA_IOCTL_OP;
3431         ad.u.op = &ioctl;
3432         ad.u.op->cmd = cmd;
3433         ad.u.op->path = file->f_path;
3434
3435         if (ssid != fsec->sid) {
3436                 rc = avc_has_perm(ssid, fsec->sid,
3437                                 SECCLASS_FD,
3438                                 FD__USE,
3439                                 &ad);
3440                 if (rc)
3441                         goto out;
3442         }
3443
3444         if (unlikely(IS_PRIVATE(inode)))
3445                 return 0;
3446
3447         isec = inode_security(inode);
3448         rc = avc_has_extended_perms(ssid, isec->sid, isec->sclass,
3449                         requested, driver, xperm, &ad);
3450 out:
3451         return rc;
3452 }
3453
3454 static int selinux_file_ioctl(struct file *file, unsigned int cmd,
3455                               unsigned long arg)
3456 {
3457         const struct cred *cred = current_cred();
3458         int error = 0;
3459
3460         switch (cmd) {
3461         case FIONREAD:
3462         /* fall through */
3463         case FIBMAP:
3464         /* fall through */
3465         case FIGETBSZ:
3466         /* fall through */
3467         case FS_IOC_GETFLAGS:
3468         /* fall through */
3469         case FS_IOC_GETVERSION:
3470                 error = file_has_perm(cred, file, FILE__GETATTR);
3471                 break;
3472
3473         case FS_IOC_SETFLAGS:
3474         /* fall through */
3475         case FS_IOC_SETVERSION:
3476                 error = file_has_perm(cred, file, FILE__SETATTR);
3477                 break;
3478
3479         /* sys_ioctl() checks */
3480         case FIONBIO:
3481         /* fall through */
3482         case FIOASYNC:
3483                 error = file_has_perm(cred, file, 0);
3484                 break;
3485
3486         case KDSKBENT:
3487         case KDSKBSENT:
3488                 error = cred_has_capability(cred, CAP_SYS_TTY_CONFIG,
3489                                             SECURITY_CAP_AUDIT, true);
3490                 break;
3491
3492         /* default case assumes that the command will go
3493          * to the file's ioctl() function.
3494          */
3495         default:
3496                 error = ioctl_has_perm(cred, file, FILE__IOCTL, (u16) cmd);
3497         }
3498         return error;
3499 }
3500
3501 static int default_noexec;
3502
3503 static int file_map_prot_check(struct file *file, unsigned long prot, int shared)
3504 {
3505         const struct cred *cred = current_cred();
3506         int rc = 0;
3507
3508         if (default_noexec &&
3509             (prot & PROT_EXEC) && (!file || IS_PRIVATE(file_inode(file)) ||
3510                                    (!shared && (prot & PROT_WRITE)))) {
3511                 /*
3512                  * We are making executable an anonymous mapping or a
3513                  * private file mapping that will also be writable.
3514                  * This has an additional check.
3515                  */
3516                 rc = cred_has_perm(cred, cred, PROCESS__EXECMEM);
3517                 if (rc)
3518                         goto error;
3519         }
3520
3521         if (file) {
3522                 /* read access is always possible with a mapping */
3523                 u32 av = FILE__READ;
3524
3525                 /* write access only matters if the mapping is shared */
3526                 if (shared && (prot & PROT_WRITE))
3527                         av |= FILE__WRITE;
3528
3529                 if (prot & PROT_EXEC)
3530                         av |= FILE__EXECUTE;
3531
3532                 return file_has_perm(cred, file, av);
3533         }
3534
3535 error:
3536         return rc;
3537 }
3538
3539 static int selinux_mmap_addr(unsigned long addr)
3540 {
3541         int rc = 0;
3542
3543         if (addr < CONFIG_LSM_MMAP_MIN_ADDR) {
3544                 u32 sid = current_sid();
3545                 rc = avc_has_perm(sid, sid, SECCLASS_MEMPROTECT,
3546                                   MEMPROTECT__MMAP_ZERO, NULL);
3547         }
3548
3549         return rc;
3550 }
3551
3552 static int selinux_mmap_file(struct file *file, unsigned long reqprot,
3553                              unsigned long prot, unsigned long flags)
3554 {
3555         if (selinux_checkreqprot)
3556                 prot = reqprot;
3557
3558         return file_map_prot_check(file, prot,
3559                                    (flags & MAP_TYPE) == MAP_SHARED);
3560 }
3561
3562 static int selinux_file_mprotect(struct vm_area_struct *vma,
3563                                  unsigned long reqprot,
3564                                  unsigned long prot)
3565 {
3566         const struct cred *cred = current_cred();
3567
3568         if (selinux_checkreqprot)
3569                 prot = reqprot;
3570
3571         if (default_noexec &&
3572             (prot & PROT_EXEC) && !(vma->vm_flags & VM_EXEC)) {
3573                 int rc = 0;
3574                 if (vma->vm_start >= vma->vm_mm->start_brk &&
3575                     vma->vm_end <= vma->vm_mm->brk) {
3576                         rc = cred_has_perm(cred, cred, PROCESS__EXECHEAP);
3577                 } else if (!vma->vm_file &&
3578                            ((vma->vm_start <= vma->vm_mm->start_stack &&
3579                              vma->vm_end >= vma->vm_mm->start_stack) ||
3580                             vma_is_stack_for_current(vma))) {
3581                         rc = current_has_perm(current, PROCESS__EXECSTACK);
3582                 } else if (vma->vm_file && vma->anon_vma) {
3583                         /*
3584                          * We are making executable a file mapping that has
3585                          * had some COW done. Since pages might have been
3586                          * written, check ability to execute the possibly
3587                          * modified content.  This typically should only
3588                          * occur for text relocations.
3589                          */
3590                         rc = file_has_perm(cred, vma->vm_file, FILE__EXECMOD);
3591                 }
3592                 if (rc)
3593                         return rc;
3594         }
3595
3596         return file_map_prot_check(vma->vm_file, prot, vma->vm_flags&VM_SHARED);
3597 }
3598
3599 static int selinux_file_lock(struct file *file, unsigned int cmd)
3600 {
3601         const struct cred *cred = current_cred();
3602
3603         return file_has_perm(cred, file, FILE__LOCK);
3604 }
3605
3606 static int selinux_file_fcntl(struct file *file, unsigned int cmd,
3607                               unsigned long arg)
3608 {
3609         const struct cred *cred = current_cred();
3610         int err = 0;
3611
3612         switch (cmd) {
3613         case F_SETFL:
3614                 if ((file->f_flags & O_APPEND) && !(arg & O_APPEND)) {
3615                         err = file_has_perm(cred, file, FILE__WRITE);
3616                         break;
3617                 }
3618                 /* fall through */
3619         case F_SETOWN:
3620         case F_SETSIG:
3621         case F_GETFL:
3622         case F_GETOWN:
3623         case F_GETSIG:
3624         case F_GETOWNER_UIDS:
3625                 /* Just check FD__USE permission */
3626                 err = file_has_perm(cred, file, 0);
3627                 break;
3628         case F_GETLK:
3629         case F_SETLK:
3630         case F_SETLKW:
3631         case F_OFD_GETLK:
3632         case F_OFD_SETLK:
3633         case F_OFD_SETLKW:
3634 #if BITS_PER_LONG == 32
3635         case F_GETLK64:
3636         case F_SETLK64:
3637         case F_SETLKW64:
3638 #endif
3639                 err = file_has_perm(cred, file, FILE__LOCK);
3640                 break;
3641         }
3642
3643         return err;
3644 }
3645
3646 static void selinux_file_set_fowner(struct file *file)
3647 {
3648         struct file_security_struct *fsec;
3649
3650         fsec = file->f_security;
3651         fsec->fown_sid = current_sid();
3652 }
3653
3654 static int selinux_file_send_sigiotask(struct task_struct *tsk,
3655                                        struct fown_struct *fown, int signum)
3656 {
3657         struct file *file;
3658         u32 sid = task_sid(tsk);
3659         u32 perm;
3660         struct file_security_struct *fsec;
3661
3662         /* struct fown_struct is never outside the context of a struct file */
3663         file = container_of(fown, struct file, f_owner);
3664
3665         fsec = file->f_security;
3666
3667         if (!signum)
3668                 perm = signal_to_av(SIGIO); /* as per send_sigio_to_task */
3669         else
3670                 perm = signal_to_av(signum);
3671
3672         return avc_has_perm(fsec->fown_sid, sid,
3673                             SECCLASS_PROCESS, perm, NULL);
3674 }
3675
3676 static int selinux_file_receive(struct file *file)
3677 {
3678         const struct cred *cred = current_cred();
3679
3680         return file_has_perm(cred, file, file_to_av(file));
3681 }
3682
3683 static int selinux_file_open(struct file *file, const struct cred *cred)
3684 {
3685         struct file_security_struct *fsec;
3686         struct inode_security_struct *isec;
3687
3688         fsec = file->f_security;
3689         isec = inode_security(file_inode(file));
3690         /*
3691          * Save inode label and policy sequence number
3692          * at open-time so that selinux_file_permission
3693          * can determine whether revalidation is necessary.
3694          * Task label is already saved in the file security
3695          * struct as its SID.
3696          */
3697         fsec->isid = isec->sid;
3698         fsec->pseqno = avc_policy_seqno();
3699         /*
3700          * Since the inode label or policy seqno may have changed
3701          * between the selinux_inode_permission check and the saving
3702          * of state above, recheck that access is still permitted.
3703          * Otherwise, access might never be revalidated against the
3704          * new inode label or new policy.
3705          * This check is not redundant - do not remove.
3706          */
3707         return file_path_has_perm(cred, file, open_file_to_av(file));
3708 }
3709
3710 /* task security operations */
3711
3712 static int selinux_task_create(unsigned long clone_flags)
3713 {
3714         return current_has_perm(current, PROCESS__FORK);
3715 }
3716
3717 /*
3718  * allocate the SELinux part of blank credentials
3719  */
3720 static int selinux_cred_alloc_blank(struct cred *cred, gfp_t gfp)
3721 {
3722         struct task_security_struct *tsec;
3723
3724         tsec = kzalloc(sizeof(struct task_security_struct), gfp);
3725         if (!tsec)
3726                 return -ENOMEM;
3727
3728         cred->security = tsec;
3729         return 0;
3730 }
3731
3732 /*
3733  * detach and free the LSM part of a set of credentials
3734  */
3735 static void selinux_cred_free(struct cred *cred)
3736 {
3737         struct task_security_struct *tsec = cred->security;
3738
3739         /*
3740          * cred->security == NULL if security_cred_alloc_blank() or
3741          * security_prepare_creds() returned an error.
3742          */
3743         BUG_ON(cred->security && (unsigned long) cred->security < PAGE_SIZE);
3744         cred->security = (void *) 0x7UL;
3745         kfree(tsec);
3746 }
3747
3748 /*
3749  * prepare a new set of credentials for modification
3750  */
3751 static int selinux_cred_prepare(struct cred *new, const struct cred *old,
3752                                 gfp_t gfp)
3753 {
3754         const struct task_security_struct *old_tsec;
3755         struct task_security_struct *tsec;
3756
3757         old_tsec = old->security;
3758
3759         tsec = kmemdup(old_tsec, sizeof(struct task_security_struct), gfp);
3760         if (!tsec)
3761                 return -ENOMEM;
3762
3763         new->security = tsec;
3764         return 0;
3765 }
3766
3767 /*
3768  * transfer the SELinux data to a blank set of creds
3769  */
3770 static void selinux_cred_transfer(struct cred *new, const struct cred *old)
3771 {
3772         const struct task_security_struct *old_tsec = old->security;
3773         struct task_security_struct *tsec = new->security;
3774
3775         *tsec = *old_tsec;
3776 }
3777
3778 /*
3779  * set the security data for a kernel service
3780  * - all the creation contexts are set to unlabelled
3781  */
3782 static int selinux_kernel_act_as(struct cred *new, u32 secid)
3783 {
3784         struct task_security_struct *tsec = new->security;
3785         u32 sid = current_sid();
3786         int ret;
3787
3788         ret = avc_has_perm(sid, secid,
3789                            SECCLASS_KERNEL_SERVICE,
3790                            KERNEL_SERVICE__USE_AS_OVERRIDE,
3791                            NULL);
3792         if (ret == 0) {
3793                 tsec->sid = secid;
3794                 tsec->create_sid = 0;
3795                 tsec->keycreate_sid = 0;
3796                 tsec->sockcreate_sid = 0;
3797         }
3798         return ret;
3799 }
3800
3801 /*
3802  * set the file creation context in a security record to the same as the
3803  * objective context of the specified inode
3804  */
3805 static int selinux_kernel_create_files_as(struct cred *new, struct inode *inode)
3806 {
3807         struct inode_security_struct *isec = inode_security(inode);
3808         struct task_security_struct *tsec = new->security;
3809         u32 sid = current_sid();
3810         int ret;
3811
3812         ret = avc_has_perm(sid, isec->sid,
3813                            SECCLASS_KERNEL_SERVICE,
3814                            KERNEL_SERVICE__CREATE_FILES_AS,
3815                            NULL);
3816
3817         if (ret == 0)
3818                 tsec->create_sid = isec->sid;
3819         return ret;
3820 }
3821
3822 static int selinux_kernel_module_request(char *kmod_name)
3823 {
3824         u32 sid;
3825         struct common_audit_data ad;
3826
3827         sid = task_sid(current);
3828
3829         ad.type = LSM_AUDIT_DATA_KMOD;
3830         ad.u.kmod_name = kmod_name;
3831
3832         return avc_has_perm(sid, SECINITSID_KERNEL, SECCLASS_SYSTEM,
3833                             SYSTEM__MODULE_REQUEST, &ad);
3834 }
3835
3836 static int selinux_kernel_module_from_file(struct file *file)
3837 {
3838         struct common_audit_data ad;
3839         struct inode_security_struct *isec;
3840         struct file_security_struct *fsec;
3841         u32 sid = current_sid();
3842         int rc;
3843
3844         /* init_module */
3845         if (file == NULL)
3846                 return avc_has_perm(sid, sid, SECCLASS_SYSTEM,
3847                                         SYSTEM__MODULE_LOAD, NULL);
3848
3849         /* finit_module */
3850
3851         ad.type = LSM_AUDIT_DATA_FILE;
3852         ad.u.file = file;
3853
3854         fsec = file->f_security;
3855         if (sid != fsec->sid) {
3856                 rc = avc_has_perm(sid, fsec->sid, SECCLASS_FD, FD__USE, &ad);
3857                 if (rc)
3858                         return rc;
3859         }
3860
3861         isec = inode_security(file_inode(file));
3862         return avc_has_perm(sid, isec->sid, SECCLASS_SYSTEM,
3863                                 SYSTEM__MODULE_LOAD, &ad);
3864 }
3865
3866 static int selinux_kernel_read_file(struct file *file,
3867                                     enum kernel_read_file_id id)
3868 {
3869         int rc = 0;
3870
3871         switch (id) {
3872         case READING_MODULE:
3873                 rc = selinux_kernel_module_from_file(file);
3874                 break;
3875         default:
3876                 break;
3877         }
3878
3879         return rc;
3880 }
3881
3882 static int selinux_task_setpgid(struct task_struct *p, pid_t pgid)
3883 {
3884         return current_has_perm(p, PROCESS__SETPGID);
3885 }
3886
3887 static int selinux_task_getpgid(struct task_struct *p)
3888 {
3889         return current_has_perm(p, PROCESS__GETPGID);
3890 }
3891
3892 static int selinux_task_getsid(struct task_struct *p)
3893 {
3894         return current_has_perm(p, PROCESS__GETSESSION);
3895 }
3896
3897 static void selinux_task_getsecid(struct task_struct *p, u32 *secid)
3898 {
3899         *secid = task_sid(p);
3900 }
3901
3902 static int selinux_task_setnice(struct task_struct *p, int nice)
3903 {
3904         return current_has_perm(p, PROCESS__SETSCHED);
3905 }
3906
3907 static int selinux_task_setioprio(struct task_struct *p, int ioprio)
3908 {
3909         return current_has_perm(p, PROCESS__SETSCHED);
3910 }
3911
3912 static int selinux_task_getioprio(struct task_struct *p)
3913 {
3914         return current_has_perm(p, PROCESS__GETSCHED);
3915 }
3916
3917 static int selinux_task_setrlimit(struct task_struct *p, unsigned int resource,
3918                 struct rlimit *new_rlim)
3919 {
3920         struct rlimit *old_rlim = p->signal->rlim + resource;
3921
3922         /* Control the ability to change the hard limit (whether
3923            lowering or raising it), so that the hard limit can
3924            later be used as a safe reset point for the soft limit
3925            upon context transitions.  See selinux_bprm_committing_creds. */
3926         if (old_rlim->rlim_max != new_rlim->rlim_max)
3927                 return current_has_perm(p, PROCESS__SETRLIMIT);
3928
3929         return 0;
3930 }
3931
3932 static int selinux_task_setscheduler(struct task_struct *p)
3933 {
3934         return current_has_perm(p, PROCESS__SETSCHED);
3935 }
3936
3937 static int selinux_task_getscheduler(struct task_struct *p)
3938 {
3939         return current_has_perm(p, PROCESS__GETSCHED);
3940 }
3941
3942 static int selinux_task_movememory(struct task_struct *p)
3943 {
3944         return current_has_perm(p, PROCESS__SETSCHED);
3945 }
3946
3947 static int selinux_task_kill(struct task_struct *p, struct siginfo *info,
3948                                 int sig, u32 secid)
3949 {
3950         u32 perm;
3951         int rc;
3952
3953         if (!sig)
3954                 perm = PROCESS__SIGNULL; /* null signal; existence test */
3955         else
3956                 perm = signal_to_av(sig);
3957         if (secid)
3958                 rc = avc_has_perm(secid, task_sid(p),
3959                                   SECCLASS_PROCESS, perm, NULL);
3960         else
3961                 rc = current_has_perm(p, perm);
3962         return rc;
3963 }
3964
3965 static int selinux_task_wait(struct task_struct *p)
3966 {
3967         return task_has_perm(p, current, PROCESS__SIGCHLD);
3968 }
3969
3970 static void selinux_task_to_inode(struct task_struct *p,
3971                                   struct inode *inode)
3972 {
3973         struct inode_security_struct *isec = inode->i_security;
3974         u32 sid = task_sid(p);
3975
3976         spin_lock(&isec->lock);
3977         isec->sclass = inode_mode_to_security_class(inode->i_mode);
3978         isec->sid = sid;
3979         isec->initialized = LABEL_INITIALIZED;
3980         spin_unlock(&isec->lock);
3981 }
3982
3983 /* Returns error only if unable to parse addresses */
3984 static int selinux_parse_skb_ipv4(struct sk_buff *skb,
3985                         struct common_audit_data *ad, u8 *proto)
3986 {
3987         int offset, ihlen, ret = -EINVAL;
3988         struct iphdr _iph, *ih;
3989
3990         offset = skb_network_offset(skb);
3991         ih = skb_header_pointer(skb, offset, sizeof(_iph), &_iph);
3992         if (ih == NULL)
3993                 goto out;
3994
3995         ihlen = ih->ihl * 4;
3996         if (ihlen < sizeof(_iph))
3997                 goto out;
3998
3999         ad->u.net->v4info.saddr = ih->saddr;
4000         ad->u.net->v4info.daddr = ih->daddr;
4001         ret = 0;
4002
4003         if (proto)
4004                 *proto = ih->protocol;
4005
4006         switch (ih->protocol) {
4007         case IPPROTO_TCP: {
4008                 struct tcphdr _tcph, *th;
4009
4010                 if (ntohs(ih->frag_off) & IP_OFFSET)
4011                         break;
4012
4013                 offset += ihlen;
4014                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4015                 if (th == NULL)
4016                         break;
4017
4018                 ad->u.net->sport = th->source;
4019                 ad->u.net->dport = th->dest;
4020                 break;
4021         }
4022
4023         case IPPROTO_UDP: {
4024                 struct udphdr _udph, *uh;
4025
4026                 if (ntohs(ih->frag_off) & IP_OFFSET)
4027                         break;
4028
4029                 offset += ihlen;
4030                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4031                 if (uh == NULL)
4032                         break;
4033
4034                 ad->u.net->sport = uh->source;
4035                 ad->u.net->dport = uh->dest;
4036                 break;
4037         }
4038
4039         case IPPROTO_DCCP: {
4040                 struct dccp_hdr _dccph, *dh;
4041
4042                 if (ntohs(ih->frag_off) & IP_OFFSET)
4043                         break;
4044
4045                 offset += ihlen;
4046                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4047                 if (dh == NULL)
4048                         break;
4049
4050                 ad->u.net->sport = dh->dccph_sport;
4051                 ad->u.net->dport = dh->dccph_dport;
4052                 break;
4053         }
4054
4055         default:
4056                 break;
4057         }
4058 out:
4059         return ret;
4060 }
4061
4062 #if IS_ENABLED(CONFIG_IPV6)
4063
4064 /* Returns error only if unable to parse addresses */
4065 static int selinux_parse_skb_ipv6(struct sk_buff *skb,
4066                         struct common_audit_data *ad, u8 *proto)
4067 {
4068         u8 nexthdr;
4069         int ret = -EINVAL, offset;
4070         struct ipv6hdr _ipv6h, *ip6;
4071         __be16 frag_off;
4072
4073         offset = skb_network_offset(skb);
4074         ip6 = skb_header_pointer(skb, offset, sizeof(_ipv6h), &_ipv6h);
4075         if (ip6 == NULL)
4076                 goto out;
4077
4078         ad->u.net->v6info.saddr = ip6->saddr;
4079         ad->u.net->v6info.daddr = ip6->daddr;
4080         ret = 0;
4081
4082         nexthdr = ip6->nexthdr;
4083         offset += sizeof(_ipv6h);
4084         offset = ipv6_skip_exthdr(skb, offset, &nexthdr, &frag_off);
4085         if (offset < 0)
4086                 goto out;
4087
4088         if (proto)
4089                 *proto = nexthdr;
4090
4091         switch (nexthdr) {
4092         case IPPROTO_TCP: {
4093                 struct tcphdr _tcph, *th;
4094
4095                 th = skb_header_pointer(skb, offset, sizeof(_tcph), &_tcph);
4096                 if (th == NULL)
4097                         break;
4098
4099                 ad->u.net->sport = th->source;
4100                 ad->u.net->dport = th->dest;
4101                 break;
4102         }
4103
4104         case IPPROTO_UDP: {
4105                 struct udphdr _udph, *uh;
4106
4107                 uh = skb_header_pointer(skb, offset, sizeof(_udph), &_udph);
4108                 if (uh == NULL)
4109                         break;
4110
4111                 ad->u.net->sport = uh->source;
4112                 ad->u.net->dport = uh->dest;
4113                 break;
4114         }
4115
4116         case IPPROTO_DCCP: {
4117                 struct dccp_hdr _dccph, *dh;
4118
4119                 dh = skb_header_pointer(skb, offset, sizeof(_dccph), &_dccph);
4120                 if (dh == NULL)
4121                         break;
4122
4123                 ad->u.net->sport = dh->dccph_sport;
4124                 ad->u.net->dport = dh->dccph_dport;
4125                 break;
4126         }
4127
4128         /* includes fragments */
4129         default:
4130                 break;
4131         }
4132 out:
4133         return ret;
4134 }
4135
4136 #endif /* IPV6 */
4137
4138 static int selinux_parse_skb(struct sk_buff *skb, struct common_audit_data *ad,
4139                              char **_addrp, int src, u8 *proto)
4140 {
4141         char *addrp;
4142         int ret;
4143
4144         switch (ad->u.net->family) {
4145         case PF_INET:
4146                 ret = selinux_parse_skb_ipv4(skb, ad, proto);
4147                 if (ret)
4148                         goto parse_error;
4149                 addrp = (char *)(src ? &ad->u.net->v4info.saddr :
4150                                        &ad->u.net->v4info.daddr);
4151                 goto okay;
4152
4153 #if IS_ENABLED(CONFIG_IPV6)
4154         case PF_INET6:
4155                 ret = selinux_parse_skb_ipv6(skb, ad, proto);
4156                 if (ret)
4157                         goto parse_error;
4158                 addrp = (char *)(src ? &ad->u.net->v6info.saddr :
4159                                        &ad->u.net->v6info.daddr);
4160                 goto okay;
4161 #endif  /* IPV6 */
4162         default:
4163                 addrp = NULL;
4164                 goto okay;
4165         }
4166
4167 parse_error:
4168         printk(KERN_WARNING
4169                "SELinux: failure in selinux_parse_skb(),"
4170                " unable to parse packet\n");
4171         return ret;
4172
4173 okay:
4174         if (_addrp)
4175                 *_addrp = addrp;
4176         return 0;
4177 }
4178
4179 /**
4180  * selinux_skb_peerlbl_sid - Determine the peer label of a packet
4181  * @skb: the packet
4182  * @family: protocol family
4183  * @sid: the packet's peer label SID
4184  *
4185  * Description:
4186  * Check the various different forms of network peer labeling and determine
4187  * the peer label/SID for the packet; most of the magic actually occurs in
4188  * the security server function security_net_peersid_cmp().  The function
4189  * returns zero if the value in @sid is valid (although it may be SECSID_NULL)
4190  * or -EACCES if @sid is invalid due to inconsistencies with the different
4191  * peer labels.
4192  *
4193  */
4194 static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
4195 {
4196         int err;
4197         u32 xfrm_sid;
4198         u32 nlbl_sid;
4199         u32 nlbl_type;
4200
4201         err = selinux_xfrm_skb_sid(skb, &xfrm_sid);
4202         if (unlikely(err))
4203                 return -EACCES;
4204         err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
4205         if (unlikely(err))
4206                 return -EACCES;
4207
4208         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
4209         if (unlikely(err)) {
4210                 printk(KERN_WARNING
4211                        "SELinux: failure in selinux_skb_peerlbl_sid(),"
4212                        " unable to determine packet's peer label\n");
4213                 return -EACCES;
4214         }
4215
4216         return 0;
4217 }
4218
4219 /**
4220  * selinux_conn_sid - Determine the child socket label for a connection
4221  * @sk_sid: the parent socket's SID
4222  * @skb_sid: the packet's SID
4223  * @conn_sid: the resulting connection SID
4224  *
4225  * If @skb_sid is valid then the user:role:type information from @sk_sid is
4226  * combined with the MLS information from @skb_sid in order to create
4227  * @conn_sid.  If @skb_sid is not valid then then @conn_sid is simply a copy
4228  * of @sk_sid.  Returns zero on success, negative values on failure.
4229  *
4230  */
4231 static int selinux_conn_sid(u32 sk_sid, u32 skb_sid, u32 *conn_sid)
4232 {
4233         int err = 0;
4234
4235         if (skb_sid != SECSID_NULL)
4236                 err = security_sid_mls_copy(sk_sid, skb_sid, conn_sid);
4237         else
4238                 *conn_sid = sk_sid;
4239
4240         return err;
4241 }
4242
4243 /* socket security operations */
4244
4245 static int socket_sockcreate_sid(const struct task_security_struct *tsec,
4246                                  u16 secclass, u32 *socksid)
4247 {
4248         if (tsec->sockcreate_sid > SECSID_NULL) {
4249                 *socksid = tsec->sockcreate_sid;
4250                 return 0;
4251         }
4252
4253         return security_transition_sid(tsec->sid, tsec->sid, secclass, NULL,
4254                                        socksid);
4255 }
4256
4257 static int sock_has_perm(struct task_struct *task, struct sock *sk, u32 perms)
4258 {
4259         struct sk_security_struct *sksec = sk->sk_security;
4260         struct common_audit_data ad;
4261         struct lsm_network_audit net = {0,};
4262         u32 tsid = task_sid(task);
4263
4264         if (sksec->sid == SECINITSID_KERNEL)
4265                 return 0;
4266
4267         ad.type = LSM_AUDIT_DATA_NET;
4268         ad.u.net = &net;
4269         ad.u.net->sk = sk;
4270
4271         return avc_has_perm(tsid, sksec->sid, sksec->sclass, perms, &ad);
4272 }
4273
4274 static int selinux_socket_create(int family, int type,
4275                                  int protocol, int kern)
4276 {
4277         const struct task_security_struct *tsec = current_security();
4278         u32 newsid;
4279         u16 secclass;
4280         int rc;
4281
4282         if (kern)
4283                 return 0;
4284
4285         secclass = socket_type_to_security_class(family, type, protocol);
4286         rc = socket_sockcreate_sid(tsec, secclass, &newsid);
4287         if (rc)
4288                 return rc;
4289
4290         return avc_has_perm(tsec->sid, newsid, secclass, SOCKET__CREATE, NULL);
4291 }
4292
4293 static int selinux_socket_post_create(struct socket *sock, int family,
4294                                       int type, int protocol, int kern)
4295 {
4296         const struct task_security_struct *tsec = current_security();
4297         struct inode_security_struct *isec = inode_security_novalidate(SOCK_INODE(sock));
4298         struct sk_security_struct *sksec;
4299         u16 sclass = socket_type_to_security_class(family, type, protocol);
4300         u32 sid = SECINITSID_KERNEL;
4301         int err = 0;
4302
4303         if (!kern) {
4304                 err = socket_sockcreate_sid(tsec, sclass, &sid);
4305                 if (err)
4306                         return err;
4307         }
4308
4309         isec->sclass = sclass;
4310         isec->sid = sid;
4311         isec->initialized = LABEL_INITIALIZED;
4312
4313         if (sock->sk) {
4314                 sksec = sock->sk->sk_security;
4315                 sksec->sclass = sclass;
4316                 sksec->sid = sid;
4317                 err = selinux_netlbl_socket_post_create(sock->sk, family);
4318         }
4319
4320         return err;
4321 }
4322
4323 /* Range of port numbers used to automatically bind.
4324    Need to determine whether we should perform a name_bind
4325    permission check between the socket and the port number. */
4326
4327 static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen)
4328 {
4329         struct sock *sk = sock->sk;
4330         u16 family;
4331         int err;
4332
4333         err = sock_has_perm(current, sk, SOCKET__BIND);
4334         if (err)
4335                 goto out;
4336
4337         /*
4338          * If PF_INET or PF_INET6, check name_bind permission for the port.
4339          * Multiple address binding for SCTP is not supported yet: we just
4340          * check the first address now.
4341          */
4342         family = sk->sk_family;
4343         if (family == PF_INET || family == PF_INET6) {
4344                 char *addrp;
4345                 struct sk_security_struct *sksec = sk->sk_security;
4346                 struct common_audit_data ad;
4347                 struct lsm_network_audit net = {0,};
4348                 struct sockaddr_in *addr4 = NULL;
4349                 struct sockaddr_in6 *addr6 = NULL;
4350                 unsigned short snum;
4351                 u32 sid, node_perm;
4352
4353                 if (family == PF_INET) {
4354                         addr4 = (struct sockaddr_in *)address;
4355                         snum = ntohs(addr4->sin_port);
4356                         addrp = (char *)&addr4->sin_addr.s_addr;
4357                 } else {
4358                         addr6 = (struct sockaddr_in6 *)address;
4359                         snum = ntohs(addr6->sin6_port);
4360                         addrp = (char *)&addr6->sin6_addr.s6_addr;
4361                 }
4362
4363                 if (snum) {
4364                         int low, high;
4365
4366                         inet_get_local_port_range(sock_net(sk), &low, &high);
4367
4368                         if (snum < max(inet_prot_sock(sock_net(sk)), low) ||
4369                             snum > high) {
4370                                 err = sel_netport_sid(sk->sk_protocol,
4371                                                       snum, &sid);
4372                                 if (err)
4373                                         goto out;
4374                                 ad.type = LSM_AUDIT_DATA_NET;
4375                                 ad.u.net = &net;
4376                                 ad.u.net->sport = htons(snum);
4377                                 ad.u.net->family = family;
4378                                 err = avc_has_perm(sksec->sid, sid,
4379                                                    sksec->sclass,
4380                                                    SOCKET__NAME_BIND, &ad);
4381                                 if (err)
4382                                         goto out;
4383                         }
4384                 }
4385
4386                 switch (sksec->sclass) {
4387                 case SECCLASS_TCP_SOCKET:
4388                         node_perm = TCP_SOCKET__NODE_BIND;
4389                         break;
4390
4391                 case SECCLASS_UDP_SOCKET:
4392                         node_perm = UDP_SOCKET__NODE_BIND;
4393                         break;
4394
4395                 case SECCLASS_DCCP_SOCKET:
4396                         node_perm = DCCP_SOCKET__NODE_BIND;
4397                         break;
4398
4399                 default:
4400                         node_perm = RAWIP_SOCKET__NODE_BIND;
4401                         break;
4402                 }
4403
4404                 err = sel_netnode_sid(addrp, family, &sid);
4405                 if (err)
4406                         goto out;
4407
4408                 ad.type = LSM_AUDIT_DATA_NET;
4409                 ad.u.net = &net;
4410                 ad.u.net->sport = htons(snum);
4411                 ad.u.net->family = family;
4412
4413                 if (family == PF_INET)
4414                         ad.u.net->v4info.saddr = addr4->sin_addr.s_addr;
4415                 else
4416                         ad.u.net->v6info.saddr = addr6->sin6_addr;
4417
4418                 err = avc_has_perm(sksec->sid, sid,
4419                                    sksec->sclass, node_perm, &ad);
4420                 if (err)
4421                         goto out;
4422         }
4423 out:
4424         return err;
4425 }
4426
4427 static int selinux_socket_connect(struct socket *sock, struct sockaddr *address, int addrlen)
4428 {
4429         struct sock *sk = sock->sk;
4430         struct sk_security_struct *sksec = sk->sk_security;
4431         int err;
4432
4433         err = sock_has_perm(current, sk, SOCKET__CONNECT);
4434         if (err)
4435                 return err;
4436
4437         /*
4438          * If a TCP or DCCP socket, check name_connect permission for the port.
4439          */
4440         if (sksec->sclass == SECCLASS_TCP_SOCKET ||
4441             sksec->sclass == SECCLASS_DCCP_SOCKET) {
4442                 struct common_audit_data ad;
4443                 struct lsm_network_audit net = {0,};
4444                 struct sockaddr_in *addr4 = NULL;
4445                 struct sockaddr_in6 *addr6 = NULL;
4446                 unsigned short snum;
4447                 u32 sid, perm;
4448
4449                 if (sk->sk_family == PF_INET) {
4450                         addr4 = (struct sockaddr_in *)address;
4451                         if (addrlen < sizeof(struct sockaddr_in))
4452                                 return -EINVAL;
4453                         snum = ntohs(addr4->sin_port);
4454                 } else {
4455                         addr6 = (struct sockaddr_in6 *)address;
4456                         if (addrlen < SIN6_LEN_RFC2133)
4457                                 return -EINVAL;
4458                         snum = ntohs(addr6->sin6_port);
4459                 }
4460
4461                 err = sel_netport_sid(sk->sk_protocol, snum, &sid);
4462                 if (err)
4463                         goto out;
4464
4465                 perm = (sksec->sclass == SECCLASS_TCP_SOCKET) ?
4466                        TCP_SOCKET__NAME_CONNECT : DCCP_SOCKET__NAME_CONNECT;
4467
4468                 ad.type = LSM_AUDIT_DATA_NET;
4469                 ad.u.net = &net;
4470                 ad.u.net->dport = htons(snum);
4471                 ad.u.net->family = sk->sk_family;
4472                 err = avc_has_perm(sksec->sid, sid, sksec->sclass, perm, &ad);
4473                 if (err)
4474                         goto out;
4475         }
4476
4477         err = selinux_netlbl_socket_connect(sk, address);
4478
4479 out:
4480         return err;
4481 }
4482
4483 static int selinux_socket_listen(struct socket *sock, int backlog)
4484 {
4485         return sock_has_perm(current, sock->sk, SOCKET__LISTEN);
4486 }
4487
4488 static int selinux_socket_accept(struct socket *sock, struct socket *newsock)
4489 {
4490         int err;
4491         struct inode_security_struct *isec;
4492         struct inode_security_struct *newisec;
4493         u16 sclass;
4494         u32 sid;
4495
4496         err = sock_has_perm(current, sock->sk, SOCKET__ACCEPT);
4497         if (err)
4498                 return err;
4499
4500         isec = inode_security_novalidate(SOCK_INODE(sock));
4501         spin_lock(&isec->lock);
4502         sclass = isec->sclass;
4503         sid = isec->sid;
4504         spin_unlock(&isec->lock);
4505
4506         newisec = inode_security_novalidate(SOCK_INODE(newsock));
4507         newisec->sclass = sclass;
4508         newisec->sid = sid;
4509         newisec->initialized = LABEL_INITIALIZED;
4510
4511         return 0;
4512 }
4513
4514 static int selinux_socket_sendmsg(struct socket *sock, struct msghdr *msg,
4515                                   int size)
4516 {
4517         return sock_has_perm(current, sock->sk, SOCKET__WRITE);
4518 }
4519
4520 static int selinux_socket_recvmsg(struct socket *sock, struct msghdr *msg,
4521                                   int size, int flags)
4522 {
4523         return sock_has_perm(current, sock->sk, SOCKET__READ);
4524 }
4525
4526 static int selinux_socket_getsockname(struct socket *sock)
4527 {
4528         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4529 }
4530
4531 static int selinux_socket_getpeername(struct socket *sock)
4532 {
4533         return sock_has_perm(current, sock->sk, SOCKET__GETATTR);
4534 }
4535
4536 static int selinux_socket_setsockopt(struct socket *sock, int level, int optname)
4537 {
4538         int err;
4539
4540         err = sock_has_perm(current, sock->sk, SOCKET__SETOPT);
4541         if (err)
4542                 return err;
4543
4544         return selinux_netlbl_socket_setsockopt(sock, level, optname);
4545 }
4546
4547 static int selinux_socket_getsockopt(struct socket *sock, int level,
4548                                      int optname)
4549 {
4550         return sock_has_perm(current, sock->sk, SOCKET__GETOPT);
4551 }
4552
4553 static int selinux_socket_shutdown(struct socket *sock, int how)
4554 {
4555         return sock_has_perm(current, sock->sk, SOCKET__SHUTDOWN);
4556 }
4557
4558 static int selinux_socket_unix_stream_connect(struct sock *sock,
4559                                               struct sock *other,
4560                                               struct sock *newsk)
4561 {
4562         struct sk_security_struct *sksec_sock = sock->sk_security;
4563         struct sk_security_struct *sksec_other = other->sk_security;
4564         struct sk_security_struct *sksec_new = newsk->sk_security;
4565         struct common_audit_data ad;
4566         struct lsm_network_audit net = {0,};
4567         int err;
4568
4569         ad.type = LSM_AUDIT_DATA_NET;
4570         ad.u.net = &net;
4571         ad.u.net->sk = other;
4572
4573         err = avc_has_perm(sksec_sock->sid, sksec_other->sid,
4574                            sksec_other->sclass,
4575                            UNIX_STREAM_SOCKET__CONNECTTO, &ad);
4576         if (err)
4577                 return err;
4578
4579         /* server child socket */
4580         sksec_new->peer_sid = sksec_sock->sid;
4581         err = security_sid_mls_copy(sksec_other->sid, sksec_sock->sid,
4582                                     &sksec_new->sid);
4583         if (err)
4584                 return err;
4585
4586         /* connecting socket */
4587         sksec_sock->peer_sid = sksec_new->sid;
4588
4589         return 0;
4590 }
4591
4592 static int selinux_socket_unix_may_send(struct socket *sock,
4593                                         struct socket *other)
4594 {
4595         struct sk_security_struct *ssec = sock->sk->sk_security;
4596         struct sk_security_struct *osec = other->sk->sk_security;
4597         struct common_audit_data ad;
4598         struct lsm_network_audit net = {0,};
4599
4600         ad.type = LSM_AUDIT_DATA_NET;
4601         ad.u.net = &net;
4602         ad.u.net->sk = other->sk;
4603
4604         return avc_has_perm(ssec->sid, osec->sid, osec->sclass, SOCKET__SENDTO,
4605                             &ad);
4606 }
4607
4608 static int selinux_inet_sys_rcv_skb(struct net *ns, int ifindex,
4609                                     char *addrp, u16 family, u32 peer_sid,
4610                                     struct common_audit_data *ad)
4611 {
4612         int err;
4613         u32 if_sid;
4614         u32 node_sid;
4615
4616         err = sel_netif_sid(ns, ifindex, &if_sid);
4617         if (err)
4618                 return err;
4619         err = avc_has_perm(peer_sid, if_sid,
4620                            SECCLASS_NETIF, NETIF__INGRESS, ad);
4621         if (err)
4622                 return err;
4623
4624         err = sel_netnode_sid(addrp, family, &node_sid);
4625         if (err)
4626                 return err;
4627         return avc_has_perm(peer_sid, node_sid,
4628                             SECCLASS_NODE, NODE__RECVFROM, ad);
4629 }
4630
4631 static int selinux_sock_rcv_skb_compat(struct sock *sk, struct sk_buff *skb,
4632                                        u16 family)
4633 {
4634         int err = 0;
4635         struct sk_security_struct *sksec = sk->sk_security;
4636         u32 sk_sid = sksec->sid;
4637         struct common_audit_data ad;
4638         struct lsm_network_audit net = {0,};
4639         char *addrp;
4640
4641         ad.type = LSM_AUDIT_DATA_NET;
4642         ad.u.net = &net;
4643         ad.u.net->netif = skb->skb_iif;
4644         ad.u.net->family = family;
4645         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4646         if (err)
4647                 return err;
4648
4649         if (selinux_secmark_enabled()) {
4650                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4651                                    PACKET__RECV, &ad);
4652                 if (err)
4653                         return err;
4654         }
4655
4656         err = selinux_netlbl_sock_rcv_skb(sksec, skb, family, &ad);
4657         if (err)
4658                 return err;
4659         err = selinux_xfrm_sock_rcv_skb(sksec->sid, skb, &ad);
4660
4661         return err;
4662 }
4663
4664 static int selinux_socket_sock_rcv_skb(struct sock *sk, struct sk_buff *skb)
4665 {
4666         int err;
4667         struct sk_security_struct *sksec = sk->sk_security;
4668         u16 family = sk->sk_family;
4669         u32 sk_sid = sksec->sid;
4670         struct common_audit_data ad;
4671         struct lsm_network_audit net = {0,};
4672         char *addrp;
4673         u8 secmark_active;
4674         u8 peerlbl_active;
4675
4676         if (family != PF_INET && family != PF_INET6)
4677                 return 0;
4678
4679         /* Handle mapped IPv4 packets arriving via IPv6 sockets */
4680         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4681                 family = PF_INET;
4682
4683         /* If any sort of compatibility mode is enabled then handoff processing
4684          * to the selinux_sock_rcv_skb_compat() function to deal with the
4685          * special handling.  We do this in an attempt to keep this function
4686          * as fast and as clean as possible. */
4687         if (!selinux_policycap_netpeer)
4688                 return selinux_sock_rcv_skb_compat(sk, skb, family);
4689
4690         secmark_active = selinux_secmark_enabled();
4691         peerlbl_active = selinux_peerlbl_enabled();
4692         if (!secmark_active && !peerlbl_active)
4693                 return 0;
4694
4695         ad.type = LSM_AUDIT_DATA_NET;
4696         ad.u.net = &net;
4697         ad.u.net->netif = skb->skb_iif;
4698         ad.u.net->family = family;
4699         err = selinux_parse_skb(skb, &ad, &addrp, 1, NULL);
4700         if (err)
4701                 return err;
4702
4703         if (peerlbl_active) {
4704                 u32 peer_sid;
4705
4706                 err = selinux_skb_peerlbl_sid(skb, family, &peer_sid);
4707                 if (err)
4708                         return err;
4709                 err = selinux_inet_sys_rcv_skb(sock_net(sk), skb->skb_iif,
4710                                                addrp, family, peer_sid, &ad);
4711                 if (err) {
4712                         selinux_netlbl_err(skb, family, err, 0);
4713                         return err;
4714                 }
4715                 err = avc_has_perm(sk_sid, peer_sid, SECCLASS_PEER,
4716                                    PEER__RECV, &ad);
4717                 if (err) {
4718                         selinux_netlbl_err(skb, family, err, 0);
4719                         return err;
4720                 }
4721         }
4722
4723         if (secmark_active) {
4724                 err = avc_has_perm(sk_sid, skb->secmark, SECCLASS_PACKET,
4725                                    PACKET__RECV, &ad);
4726                 if (err)
4727                         return err;
4728         }
4729
4730         return err;
4731 }
4732
4733 static int selinux_socket_getpeersec_stream(struct socket *sock, char __user *optval,
4734                                             int __user *optlen, unsigned len)
4735 {
4736         int err = 0;
4737         char *scontext;
4738         u32 scontext_len;
4739         struct sk_security_struct *sksec = sock->sk->sk_security;
4740         u32 peer_sid = SECSID_NULL;
4741
4742         if (sksec->sclass == SECCLASS_UNIX_STREAM_SOCKET ||
4743             sksec->sclass == SECCLASS_TCP_SOCKET)
4744                 peer_sid = sksec->peer_sid;
4745         if (peer_sid == SECSID_NULL)
4746                 return -ENOPROTOOPT;
4747
4748         err = security_sid_to_context(peer_sid, &scontext, &scontext_len);
4749         if (err)
4750                 return err;
4751
4752         if (scontext_len > len) {
4753                 err = -ERANGE;
4754                 goto out_len;
4755         }
4756
4757         if (copy_to_user(optval, scontext, scontext_len))
4758                 err = -EFAULT;
4759
4760 out_len:
4761         if (put_user(scontext_len, optlen))
4762                 err = -EFAULT;
4763         kfree(scontext);
4764         return err;
4765 }
4766
4767 static int selinux_socket_getpeersec_dgram(struct socket *sock, struct sk_buff *skb, u32 *secid)
4768 {
4769         u32 peer_secid = SECSID_NULL;
4770         u16 family;
4771         struct inode_security_struct *isec;
4772
4773         if (skb && skb->protocol == htons(ETH_P_IP))
4774                 family = PF_INET;
4775         else if (skb && skb->protocol == htons(ETH_P_IPV6))
4776                 family = PF_INET6;
4777         else if (sock)
4778                 family = sock->sk->sk_family;
4779         else
4780                 goto out;
4781
4782         if (sock && family == PF_UNIX) {
4783                 isec = inode_security_novalidate(SOCK_INODE(sock));
4784                 peer_secid = isec->sid;
4785         } else if (skb)
4786                 selinux_skb_peerlbl_sid(skb, family, &peer_secid);
4787
4788 out:
4789         *secid = peer_secid;
4790         if (peer_secid == SECSID_NULL)
4791                 return -EINVAL;
4792         return 0;
4793 }
4794
4795 static int selinux_sk_alloc_security(struct sock *sk, int family, gfp_t priority)
4796 {
4797         struct sk_security_struct *sksec;
4798
4799         sksec = kzalloc(sizeof(*sksec), priority);
4800         if (!sksec)
4801                 return -ENOMEM;
4802
4803         sksec->peer_sid = SECINITSID_UNLABELED;
4804         sksec->sid = SECINITSID_UNLABELED;
4805         sksec->sclass = SECCLASS_SOCKET;
4806         selinux_netlbl_sk_security_reset(sksec);
4807         sk->sk_security = sksec;
4808
4809         return 0;
4810 }
4811
4812 static void selinux_sk_free_security(struct sock *sk)
4813 {
4814         struct sk_security_struct *sksec = sk->sk_security;
4815
4816         sk->sk_security = NULL;
4817         selinux_netlbl_sk_security_free(sksec);
4818         kfree(sksec);
4819 }
4820
4821 static void selinux_sk_clone_security(const struct sock *sk, struct sock *newsk)
4822 {
4823         struct sk_security_struct *sksec = sk->sk_security;
4824         struct sk_security_struct *newsksec = newsk->sk_security;
4825
4826         newsksec->sid = sksec->sid;
4827         newsksec->peer_sid = sksec->peer_sid;
4828         newsksec->sclass = sksec->sclass;
4829
4830         selinux_netlbl_sk_security_reset(newsksec);
4831 }
4832
4833 static void selinux_sk_getsecid(struct sock *sk, u32 *secid)
4834 {
4835         if (!sk)
4836                 *secid = SECINITSID_ANY_SOCKET;
4837         else {
4838                 struct sk_security_struct *sksec = sk->sk_security;
4839
4840                 *secid = sksec->sid;
4841         }
4842 }
4843
4844 static void selinux_sock_graft(struct sock *sk, struct socket *parent)
4845 {
4846         struct inode_security_struct *isec =
4847                 inode_security_novalidate(SOCK_INODE(parent));
4848         struct sk_security_struct *sksec = sk->sk_security;
4849
4850         if (sk->sk_family == PF_INET || sk->sk_family == PF_INET6 ||
4851             sk->sk_family == PF_UNIX)
4852                 isec->sid = sksec->sid;
4853         sksec->sclass = isec->sclass;
4854 }
4855
4856 static int selinux_inet_conn_request(struct sock *sk, struct sk_buff *skb,
4857                                      struct request_sock *req)
4858 {
4859         struct sk_security_struct *sksec = sk->sk_security;
4860         int err;
4861         u16 family = req->rsk_ops->family;
4862         u32 connsid;
4863         u32 peersid;
4864
4865         err = selinux_skb_peerlbl_sid(skb, family, &peersid);
4866         if (err)
4867                 return err;
4868         err = selinux_conn_sid(sksec->sid, peersid, &connsid);
4869         if (err)
4870                 return err;
4871         req->secid = connsid;
4872         req->peer_secid = peersid;
4873
4874         return selinux_netlbl_inet_conn_request(req, family);
4875 }
4876
4877 static void selinux_inet_csk_clone(struct sock *newsk,
4878                                    const struct request_sock *req)
4879 {
4880         struct sk_security_struct *newsksec = newsk->sk_security;
4881
4882         newsksec->sid = req->secid;
4883         newsksec->peer_sid = req->peer_secid;
4884         /* NOTE: Ideally, we should also get the isec->sid for the
4885            new socket in sync, but we don't have the isec available yet.
4886            So we will wait until sock_graft to do it, by which
4887            time it will have been created and available. */
4888
4889         /* We don't need to take any sort of lock here as we are the only
4890          * thread with access to newsksec */
4891         selinux_netlbl_inet_csk_clone(newsk, req->rsk_ops->family);
4892 }
4893
4894 static void selinux_inet_conn_established(struct sock *sk, struct sk_buff *skb)
4895 {
4896         u16 family = sk->sk_family;
4897         struct sk_security_struct *sksec = sk->sk_security;
4898
4899         /* handle mapped IPv4 packets arriving via IPv6 sockets */
4900         if (family == PF_INET6 && skb->protocol == htons(ETH_P_IP))
4901                 family = PF_INET;
4902
4903         selinux_skb_peerlbl_sid(skb, family, &sksec->peer_sid);
4904 }
4905
4906 static int selinux_secmark_relabel_packet(u32 sid)
4907 {
4908         const struct task_security_struct *__tsec;
4909         u32 tsid;
4910
4911         __tsec = current_security();
4912         tsid = __tsec->sid;
4913
4914         return avc_has_perm(tsid, sid, SECCLASS_PACKET, PACKET__RELABELTO, NULL);
4915 }
4916
4917 static void selinux_secmark_refcount_inc(void)
4918 {
4919         atomic_inc(&selinux_secmark_refcount);
4920 }
4921
4922 static void selinux_secmark_refcount_dec(void)
4923 {
4924         atomic_dec(&selinux_secmark_refcount);
4925 }
4926
4927 static void selinux_req_classify_flow(const struct request_sock *req,
4928                                       struct flowi *fl)
4929 {
4930         fl->flowi_secid = req->secid;
4931 }
4932
4933 static int selinux_tun_dev_alloc_security(void **security)
4934 {
4935         struct tun_security_struct *tunsec;
4936
4937         tunsec = kzalloc(sizeof(*tunsec), GFP_KERNEL);
4938         if (!tunsec)
4939                 return -ENOMEM;
4940         tunsec->sid = current_sid();
4941
4942         *security = tunsec;
4943         return 0;
4944 }
4945
4946 static void selinux_tun_dev_free_security(void *security)
4947 {
4948         kfree(security);
4949 }
4950
4951 static int selinux_tun_dev_create(void)
4952 {
4953         u32 sid = current_sid();
4954
4955         /* we aren't taking into account the "sockcreate" SID since the socket
4956          * that is being created here is not a socket in the traditional sense,
4957          * instead it is a private sock, accessible only to the kernel, and
4958          * representing a wide range of network traffic spanning multiple
4959          * connections unlike traditional sockets - check the TUN driver to
4960          * get a better understanding of why this socket is special */
4961
4962         return avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET, TUN_SOCKET__CREATE,
4963                             NULL);
4964 }
4965
4966 static int selinux_tun_dev_attach_queue(void *security)
4967 {
4968         struct tun_security_struct *tunsec = security;
4969
4970         return avc_has_perm(current_sid(), tunsec->sid, SECCLASS_TUN_SOCKET,
4971                             TUN_SOCKET__ATTACH_QUEUE, NULL);
4972 }
4973
4974 static int selinux_tun_dev_attach(struct sock *sk, void *security)
4975 {
4976         struct tun_security_struct *tunsec = security;
4977         struct sk_security_struct *sksec = sk->sk_security;
4978
4979         /* we don't currently perform any NetLabel based labeling here and it
4980          * isn't clear that we would want to do so anyway; while we could apply
4981          * labeling without the support of the TUN user the resulting labeled
4982          * traffic from the other end of the connection would almost certainly
4983          * cause confusion to the TUN user that had no idea network labeling
4984          * protocols were being used */
4985
4986         sksec->sid = tunsec->sid;
4987         sksec->sclass = SECCLASS_TUN_SOCKET;
4988
4989         return 0;
4990 }
4991
4992 static int selinux_tun_dev_open(void *security)
4993 {
4994         struct tun_security_struct *tunsec = security;
4995         u32 sid = current_sid();
4996         int err;
4997
4998         err = avc_has_perm(sid, tunsec->sid, SECCLASS_TUN_SOCKET,
4999                            TUN_SOCKET__RELABELFROM, NULL);
5000         if (err)
5001                 return err;
5002         err = avc_has_perm(sid, sid, SECCLASS_TUN_SOCKET,
5003                            TUN_SOCKET__RELABELTO, NULL);
5004         if (err)
5005                 return err;
5006         tunsec->sid = sid;
5007
5008         return 0;
5009 }
5010
5011 static int selinux_nlmsg_perm(struct sock *sk, struct sk_buff *skb)
5012 {
5013         int err = 0;
5014         u32 perm;
5015         struct nlmsghdr *nlh;
5016         struct sk_security_struct *sksec = sk->sk_security;
5017
5018         if (skb->len < NLMSG_HDRLEN) {
5019                 err = -EINVAL;
5020                 goto out;
5021         }
5022         nlh = nlmsg_hdr(skb);
5023
5024         err = selinux_nlmsg_lookup(sksec->sclass, nlh->nlmsg_type, &perm);
5025         if (err) {
5026                 if (err == -EINVAL) {
5027                         pr_warn_ratelimited("SELinux: unrecognized netlink"
5028                                " message: protocol=%hu nlmsg_type=%hu sclass=%s"
5029                                " pig=%d comm=%s\n",
5030                                sk->sk_protocol, nlh->nlmsg_type,
5031                                secclass_map[sksec->sclass - 1].name,
5032                                task_pid_nr(current), current->comm);
5033                         if (!selinux_enforcing || security_get_allow_unknown())
5034                                 err = 0;
5035                 }
5036
5037                 /* Ignore */
5038                 if (err == -ENOENT)
5039                         err = 0;
5040                 goto out;
5041         }
5042
5043         err = sock_has_perm(current, sk, perm);
5044 out:
5045         return err;
5046 }
5047
5048 #ifdef CONFIG_NETFILTER
5049
5050 static unsigned int selinux_ip_forward(struct sk_buff *skb,
5051                                        const struct net_device *indev,
5052                                        u16 family)
5053 {
5054         int err;
5055         char *addrp;
5056         u32 peer_sid;
5057         struct common_audit_data ad;
5058         struct lsm_network_audit net = {0,};
5059         u8 secmark_active;
5060         u8 netlbl_active;
5061         u8 peerlbl_active;
5062
5063         if (!selinux_policycap_netpeer)
5064                 return NF_ACCEPT;
5065
5066         secmark_active = selinux_secmark_enabled();
5067         netlbl_active = netlbl_enabled();
5068         peerlbl_active = selinux_peerlbl_enabled();
5069         if (!secmark_active && !peerlbl_active)
5070                 return NF_ACCEPT;
5071
5072         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid) != 0)
5073                 return NF_DROP;
5074
5075         ad.type = LSM_AUDIT_DATA_NET;
5076         ad.u.net = &net;
5077         ad.u.net->netif = indev->ifindex;
5078         ad.u.net->family = family;
5079         if (selinux_parse_skb(skb, &ad, &addrp, 1, NULL) != 0)
5080                 return NF_DROP;
5081
5082         if (peerlbl_active) {
5083                 err = selinux_inet_sys_rcv_skb(dev_net(indev), indev->ifindex,
5084                                                addrp, family, peer_sid, &ad);
5085                 if (err) {
5086                         selinux_netlbl_err(skb, family, err, 1);
5087                         return NF_DROP;
5088                 }
5089         }
5090
5091         if (secmark_active)
5092                 if (avc_has_perm(peer_sid, skb->secmark,
5093                                  SECCLASS_PACKET, PACKET__FORWARD_IN, &ad))
5094                         return NF_DROP;
5095
5096         if (netlbl_active)
5097                 /* we do this in the FORWARD path and not the POST_ROUTING
5098                  * path because we want to make sure we apply the necessary
5099                  * labeling before IPsec is applied so we can leverage AH
5100                  * protection */
5101                 if (selinux_netlbl_skbuff_setsid(skb, family, peer_sid) != 0)
5102                         return NF_DROP;
5103
5104         return NF_ACCEPT;
5105 }
5106
5107 static unsigned int selinux_ipv4_forward(void *priv,
5108                                          struct sk_buff *skb,
5109                                          const struct nf_hook_state *state)
5110 {
5111         return selinux_ip_forward(skb, state->in, PF_INET);
5112 }
5113
5114 #if IS_ENABLED(CONFIG_IPV6)
5115 static unsigned int selinux_ipv6_forward(void *priv,
5116                                          struct sk_buff *skb,
5117                                          const struct nf_hook_state *state)
5118 {
5119         return selinux_ip_forward(skb, state->in, PF_INET6);
5120 }
5121 #endif  /* IPV6 */
5122
5123 static unsigned int selinux_ip_output(struct sk_buff *skb,
5124                                       u16 family)
5125 {
5126         struct sock *sk;
5127         u32 sid;
5128
5129         if (!netlbl_enabled())
5130                 return NF_ACCEPT;
5131
5132         /* we do this in the LOCAL_OUT path and not the POST_ROUTING path
5133          * because we want to make sure we apply the necessary labeling
5134          * before IPsec is applied so we can leverage AH protection */
5135         sk = skb->sk;
5136         if (sk) {
5137                 struct sk_security_struct *sksec;
5138
5139                 if (sk_listener(sk))
5140                         /* if the socket is the listening state then this
5141                          * packet is a SYN-ACK packet which means it needs to
5142                          * be labeled based on the connection/request_sock and
5143                          * not the parent socket.  unfortunately, we can't
5144                          * lookup the request_sock yet as it isn't queued on
5145                          * the parent socket until after the SYN-ACK is sent.
5146                          * the "solution" is to simply pass the packet as-is
5147                          * as any IP option based labeling should be copied
5148                          * from the initial connection request (in the IP
5149                          * layer).  it is far from ideal, but until we get a
5150                          * security label in the packet itself this is the
5151                          * best we can do. */
5152                         return NF_ACCEPT;
5153
5154                 /* standard practice, label using the parent socket */
5155                 sksec = sk->sk_security;
5156                 sid = sksec->sid;
5157         } else
5158                 sid = SECINITSID_KERNEL;
5159         if (selinux_netlbl_skbuff_setsid(skb, family, sid) != 0)
5160                 return NF_DROP;
5161
5162         return NF_ACCEPT;
5163 }
5164
5165 static unsigned int selinux_ipv4_output(void *priv,
5166                                         struct sk_buff *skb,
5167                                         const struct nf_hook_state *state)
5168 {
5169         return selinux_ip_output(skb, PF_INET);
5170 }
5171
5172 #if IS_ENABLED(CONFIG_IPV6)
5173 static unsigned int selinux_ipv6_output(void *priv,
5174                                         struct sk_buff *skb,
5175                                         const struct nf_hook_state *state)
5176 {
5177         return selinux_ip_output(skb, PF_INET6);
5178 }
5179 #endif  /* IPV6 */
5180
5181 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
5182                                                 int ifindex,
5183                                                 u16 family)
5184 {
5185         struct sock *sk = skb_to_full_sk(skb);
5186         struct sk_security_struct *sksec;
5187         struct common_audit_data ad;
5188         struct lsm_network_audit net = {0,};
5189         char *addrp;
5190         u8 proto;
5191
5192         if (sk == NULL)
5193                 return NF_ACCEPT;
5194         sksec = sk->sk_security;
5195
5196         ad.type = LSM_AUDIT_DATA_NET;
5197         ad.u.net = &net;
5198         ad.u.net->netif = ifindex;
5199         ad.u.net->family = family;
5200         if (selinux_parse_skb(skb, &ad, &addrp, 0, &proto))
5201                 return NF_DROP;
5202
5203         if (selinux_secmark_enabled())
5204                 if (avc_has_perm(sksec->sid, skb->secmark,
5205                                  SECCLASS_PACKET, PACKET__SEND, &ad))
5206                         return NF_DROP_ERR(-ECONNREFUSED);
5207
5208         if (selinux_xfrm_postroute_last(sksec->sid, skb, &ad, proto))
5209                 return NF_DROP_ERR(-ECONNREFUSED);
5210
5211         return NF_ACCEPT;
5212 }
5213
5214 static unsigned int selinux_ip_postroute(struct sk_buff *skb,
5215                                          const struct net_device *outdev,
5216                                          u16 family)
5217 {
5218         u32 secmark_perm;
5219         u32 peer_sid;
5220         int ifindex = outdev->ifindex;
5221         struct sock *sk;
5222         struct common_audit_data ad;
5223         struct lsm_network_audit net = {0,};
5224         char *addrp;
5225         u8 secmark_active;
5226         u8 peerlbl_active;
5227
5228         /* If any sort of compatibility mode is enabled then handoff processing
5229          * to the selinux_ip_postroute_compat() function to deal with the
5230          * special handling.  We do this in an attempt to keep this function
5231          * as fast and as clean as possible. */
5232         if (!selinux_policycap_netpeer)
5233                 return selinux_ip_postroute_compat(skb, ifindex, family);
5234
5235         secmark_active = selinux_secmark_enabled();
5236         peerlbl_active = selinux_peerlbl_enabled();
5237         if (!secmark_active && !peerlbl_active)
5238                 return NF_ACCEPT;
5239
5240         sk = skb_to_full_sk(skb);
5241
5242 #ifdef CONFIG_XFRM
5243         /* If skb->dst->xfrm is non-NULL then the packet is undergoing an IPsec
5244          * packet transformation so allow the packet to pass without any checks
5245          * since we'll have another chance to perform access control checks
5246          * when the packet is on it's final way out.
5247          * NOTE: there appear to be some IPv6 multicast cases where skb->dst
5248          *       is NULL, in this case go ahead and apply access control.
5249          * NOTE: if this is a local socket (skb->sk != NULL) that is in the
5250          *       TCP listening state we cannot wait until the XFRM processing
5251          *       is done as we will miss out on the SA label if we do;
5252          *       unfortunately, this means more work, but it is only once per
5253          *       connection. */
5254         if (skb_dst(skb) != NULL && skb_dst(skb)->xfrm != NULL &&
5255             !(sk && sk_listener(sk)))
5256                 return NF_ACCEPT;
5257 #endif
5258
5259         if (sk == NULL) {
5260                 /* Without an associated socket the packet is either coming
5261                  * from the kernel or it is being forwarded; check the packet
5262                  * to determine which and if the packet is being forwarded
5263                  * query the packet directly to determine the security label. */
5264                 if (skb->skb_iif) {
5265                         secmark_perm = PACKET__FORWARD_OUT;
5266                         if (selinux_skb_peerlbl_sid(skb, family, &peer_sid))
5267                                 return NF_DROP;
5268                 } else {
5269                         secmark_perm = PACKET__SEND;
5270                         peer_sid = SECINITSID_KERNEL;
5271                 }
5272         } else if (sk_listener(sk)) {
5273                 /* Locally generated packet but the associated socket is in the
5274                  * listening state which means this is a SYN-ACK packet.  In
5275                  * this particular case the correct security label is assigned
5276                  * to the connection/request_sock but unfortunately we can't
5277                  * query the request_sock as it isn't queued on the parent
5278                  * socket until after the SYN-ACK packet is sent; the only
5279                  * viable choice is to regenerate the label like we do in
5280                  * selinux_inet_conn_request().  See also selinux_ip_output()
5281                  * for similar problems. */
5282                 u32 skb_sid;
5283                 struct sk_security_struct *sksec;
5284
5285                 sksec = sk->sk_security;
5286                 if (selinux_skb_peerlbl_sid(skb, family, &skb_sid))
5287                         return NF_DROP;
5288                 /* At this point, if the returned skb peerlbl is SECSID_NULL
5289                  * and the packet has been through at least one XFRM
5290                  * transformation then we must be dealing with the "final"
5291                  * form of labeled IPsec packet; since we've already applied
5292                  * all of our access controls on this packet we can safely
5293                  * pass the packet. */
5294                 if (skb_sid == SECSID_NULL) {
5295                         switch (family) {
5296                         case PF_INET:
5297                                 if (IPCB(skb)->flags & IPSKB_XFRM_TRANSFORMED)
5298                                         return NF_ACCEPT;
5299                                 break;
5300                         case PF_INET6:
5301                                 if (IP6CB(skb)->flags & IP6SKB_XFRM_TRANSFORMED)
5302                                         return NF_ACCEPT;
5303                                 break;
5304                         default:
5305                                 return NF_DROP_ERR(-ECONNREFUSED);
5306                         }
5307                 }
5308                 if (selinux_conn_sid(sksec->sid, skb_sid, &peer_sid))
5309                         return NF_DROP;
5310                 secmark_perm = PACKET__SEND;
5311         } else {
5312                 /* Locally generated packet, fetch the security label from the
5313                  * associated socket. */
5314                 struct sk_security_struct *sksec = sk->sk_security;
5315                 peer_sid = sksec->sid;
5316                 secmark_perm = PACKET__SEND;
5317         }
5318
5319         ad.type = LSM_AUDIT_DATA_NET;
5320         ad.u.net = &net;
5321         ad.u.net->netif = ifindex;
5322         ad.u.net->family = family;
5323         if (selinux_parse_skb(skb, &ad, &addrp, 0, NULL))
5324                 return NF_DROP;
5325
5326         if (secmark_active)
5327                 if (avc_has_perm(peer_sid, skb->secmark,
5328                                  SECCLASS_PACKET, secmark_perm, &ad))
5329                         return NF_DROP_ERR(-ECONNREFUSED);
5330
5331         if (peerlbl_active) {
5332                 u32 if_sid;
5333                 u32 node_sid;
5334
5335                 if (sel_netif_sid(dev_net(outdev), ifindex, &if_sid))
5336                         return NF_DROP;
5337                 if (avc_has_perm(peer_sid, if_sid,
5338                                  SECCLASS_NETIF, NETIF__EGRESS, &ad))
5339                         return NF_DROP_ERR(-ECONNREFUSED);
5340
5341                 if (sel_netnode_sid(addrp, family, &node_sid))
5342                         return NF_DROP;
5343                 if (avc_has_perm(peer_sid, node_sid,
5344                                  SECCLASS_NODE, NODE__SENDTO, &ad))
5345                         return NF_DROP_ERR(-ECONNREFUSED);
5346         }
5347
5348         return NF_ACCEPT;
5349 }
5350
5351 static unsigned int selinux_ipv4_postroute(void *priv,
5352                                            struct sk_buff *skb,
5353                                            const struct nf_hook_state *state)
5354 {
5355         return selinux_ip_postroute(skb, state->out, PF_INET);
5356 }
5357
5358 #if IS_ENABLED(CONFIG_IPV6)
5359 static unsigned int selinux_ipv6_postroute(void *priv,
5360                                            struct sk_buff *skb,
5361                                            const struct nf_hook_state *state)
5362 {
5363         return selinux_ip_postroute(skb, state->out, PF_INET6);
5364 }
5365 #endif  /* IPV6 */
5366
5367 #endif  /* CONFIG_NETFILTER */
5368
5369 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
5370 {
5371         return selinux_nlmsg_perm(sk, skb);
5372 }
5373
5374 static int ipc_alloc_security(struct task_struct *task,
5375                               struct kern_ipc_perm *perm,
5376                               u16 sclass)
5377 {
5378         struct ipc_security_struct *isec;
5379         u32 sid;
5380
5381         isec = kzalloc(sizeof(struct ipc_security_struct), GFP_KERNEL);
5382         if (!isec)
5383                 return -ENOMEM;
5384
5385         sid = task_sid(task);
5386         isec->sclass = sclass;
5387         isec->sid = sid;
5388         perm->security = isec;
5389
5390         return 0;
5391 }
5392
5393 static void ipc_free_security(struct kern_ipc_perm *perm)
5394 {
5395         struct ipc_security_struct *isec = perm->security;
5396         perm->security = NULL;
5397         kfree(isec);
5398 }
5399
5400 static int msg_msg_alloc_security(struct msg_msg *msg)
5401 {
5402         struct msg_security_struct *msec;
5403
5404         msec = kzalloc(sizeof(struct msg_security_struct), GFP_KERNEL);
5405         if (!msec)
5406                 return -ENOMEM;
5407
5408         msec->sid = SECINITSID_UNLABELED;
5409         msg->security = msec;
5410
5411         return 0;
5412 }
5413
5414 static void msg_msg_free_security(struct msg_msg *msg)
5415 {
5416         struct msg_security_struct *msec = msg->security;
5417
5418         msg->security = NULL;
5419         kfree(msec);
5420 }
5421
5422 static int ipc_has_perm(struct kern_ipc_perm *ipc_perms,
5423                         u32 perms)
5424 {
5425         struct ipc_security_struct *isec;
5426         struct common_audit_data ad;
5427         u32 sid = current_sid();
5428
5429         isec = ipc_perms->security;
5430
5431         ad.type = LSM_AUDIT_DATA_IPC;
5432         ad.u.ipc_id = ipc_perms->key;
5433
5434         return avc_has_perm(sid, isec->sid, isec->sclass, perms, &ad);
5435 }
5436
5437 static int selinux_msg_msg_alloc_security(struct msg_msg *msg)
5438 {
5439         return msg_msg_alloc_security(msg);
5440 }
5441
5442 static void selinux_msg_msg_free_security(struct msg_msg *msg)
5443 {
5444         msg_msg_free_security(msg);
5445 }
5446
5447 /* message queue security operations */
5448 static int selinux_msg_queue_alloc_security(struct msg_queue *msq)
5449 {
5450         struct ipc_security_struct *isec;
5451         struct common_audit_data ad;
5452         u32 sid = current_sid();
5453         int rc;
5454
5455         rc = ipc_alloc_security(current, &msq->q_perm, SECCLASS_MSGQ);
5456         if (rc)
5457                 return rc;
5458
5459         isec = msq->q_perm.security;
5460
5461         ad.type = LSM_AUDIT_DATA_IPC;
5462         ad.u.ipc_id = msq->q_perm.key;
5463
5464         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5465                           MSGQ__CREATE, &ad);
5466         if (rc) {
5467                 ipc_free_security(&msq->q_perm);
5468                 return rc;
5469         }
5470         return 0;
5471 }
5472
5473 static void selinux_msg_queue_free_security(struct msg_queue *msq)
5474 {
5475         ipc_free_security(&msq->q_perm);
5476 }
5477
5478 static int selinux_msg_queue_associate(struct msg_queue *msq, int msqflg)
5479 {
5480         struct ipc_security_struct *isec;
5481         struct common_audit_data ad;
5482         u32 sid = current_sid();
5483
5484         isec = msq->q_perm.security;
5485
5486         ad.type = LSM_AUDIT_DATA_IPC;
5487         ad.u.ipc_id = msq->q_perm.key;
5488
5489         return avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5490                             MSGQ__ASSOCIATE, &ad);
5491 }
5492
5493 static int selinux_msg_queue_msgctl(struct msg_queue *msq, int cmd)
5494 {
5495         int err;
5496         int perms;
5497
5498         switch (cmd) {
5499         case IPC_INFO:
5500         case MSG_INFO:
5501                 /* No specific object, just general system-wide information. */
5502                 return task_has_system(current, SYSTEM__IPC_INFO);
5503         case IPC_STAT:
5504         case MSG_STAT:
5505                 perms = MSGQ__GETATTR | MSGQ__ASSOCIATE;
5506                 break;
5507         case IPC_SET:
5508                 perms = MSGQ__SETATTR;
5509                 break;
5510         case IPC_RMID:
5511                 perms = MSGQ__DESTROY;
5512                 break;
5513         default:
5514                 return 0;
5515         }
5516
5517         err = ipc_has_perm(&msq->q_perm, perms);
5518         return err;
5519 }
5520
5521 static int selinux_msg_queue_msgsnd(struct msg_queue *msq, struct msg_msg *msg, int msqflg)
5522 {
5523         struct ipc_security_struct *isec;
5524         struct msg_security_struct *msec;
5525         struct common_audit_data ad;
5526         u32 sid = current_sid();
5527         int rc;
5528
5529         isec = msq->q_perm.security;
5530         msec = msg->security;
5531
5532         /*
5533          * First time through, need to assign label to the message
5534          */
5535         if (msec->sid == SECINITSID_UNLABELED) {
5536                 /*
5537                  * Compute new sid based on current process and
5538                  * message queue this message will be stored in
5539                  */
5540                 rc = security_transition_sid(sid, isec->sid, SECCLASS_MSG,
5541                                              NULL, &msec->sid);
5542                 if (rc)
5543                         return rc;
5544         }
5545
5546         ad.type = LSM_AUDIT_DATA_IPC;
5547         ad.u.ipc_id = msq->q_perm.key;
5548
5549         /* Can this process write to the queue? */
5550         rc = avc_has_perm(sid, isec->sid, SECCLASS_MSGQ,
5551                           MSGQ__WRITE, &ad);
5552         if (!rc)
5553                 /* Can this process send the message */
5554                 rc = avc_has_perm(sid, msec->sid, SECCLASS_MSG,
5555                                   MSG__SEND, &ad);
5556         if (!rc)
5557                 /* Can the message be put in the queue? */
5558                 rc = avc_has_perm(msec->sid, isec->sid, SECCLASS_MSGQ,
5559                                   MSGQ__ENQUEUE, &ad);
5560
5561         return rc;
5562 }
5563
5564 static int selinux_msg_queue_msgrcv(struct msg_queue *msq, struct msg_msg *msg,
5565                                     struct task_struct *target,
5566                                     long type, int mode)
5567 {
5568         struct ipc_security_struct *isec;
5569         struct msg_security_struct *msec;
5570         struct common_audit_data ad;
5571         u32 sid = task_sid(target);
5572         int rc;
5573
5574         isec = msq->q_perm.security;
5575         msec = msg->security;
5576
5577         ad.type = LSM_AUDIT_DATA_IPC;
5578         ad.u.ipc_id = msq->q_perm.key;
5579
5580         rc = avc_has_perm(sid, isec->sid,
5581                           SECCLASS_MSGQ, MSGQ__READ, &ad);
5582         if (!rc)
5583                 rc = avc_has_perm(sid, msec->sid,
5584                                   SECCLASS_MSG, MSG__RECEIVE, &ad);
5585         return rc;
5586 }
5587
5588 /* Shared Memory security operations */
5589 static int selinux_shm_alloc_security(struct shmid_kernel *shp)
5590 {
5591         struct ipc_security_struct *isec;
5592         struct common_audit_data ad;
5593         u32 sid = current_sid();
5594         int rc;
5595
5596         rc = ipc_alloc_security(current, &shp->shm_perm, SECCLASS_SHM);
5597         if (rc)
5598                 return rc;
5599
5600         isec = shp->shm_perm.security;
5601
5602         ad.type = LSM_AUDIT_DATA_IPC;
5603         ad.u.ipc_id = shp->shm_perm.key;
5604
5605         rc = avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5606                           SHM__CREATE, &ad);
5607         if (rc) {
5608                 ipc_free_security(&shp->shm_perm);
5609                 return rc;
5610         }
5611         return 0;
5612 }
5613
5614 static void selinux_shm_free_security(struct shmid_kernel *shp)
5615 {
5616         ipc_free_security(&shp->shm_perm);
5617 }
5618
5619 static int selinux_shm_associate(struct shmid_kernel *shp, int shmflg)
5620 {
5621         struct ipc_security_struct *isec;
5622         struct common_audit_data ad;
5623         u32 sid = current_sid();
5624
5625         isec = shp->shm_perm.security;
5626
5627         ad.type = LSM_AUDIT_DATA_IPC;
5628         ad.u.ipc_id = shp->shm_perm.key;
5629
5630         return avc_has_perm(sid, isec->sid, SECCLASS_SHM,
5631                             SHM__ASSOCIATE, &ad);
5632 }
5633
5634 /* Note, at this point, shp is locked down */
5635 static int selinux_shm_shmctl(struct shmid_kernel *shp, int cmd)
5636 {
5637         int perms;
5638         int err;
5639
5640         switch (cmd) {
5641         case IPC_INFO:
5642         case SHM_INFO:
5643                 /* No specific object, just general system-wide information. */
5644                 return task_has_system(current, SYSTEM__IPC_INFO);
5645         case IPC_STAT:
5646         case SHM_STAT:
5647                 perms = SHM__GETATTR | SHM__ASSOCIATE;
5648                 break;
5649         case IPC_SET:
5650                 perms = SHM__SETATTR;
5651                 break;
5652         case SHM_LOCK:
5653         case SHM_UNLOCK:
5654                 perms = SHM__LOCK;
5655                 break;
5656         case IPC_RMID:
5657                 perms = SHM__DESTROY;
5658                 break;
5659         default:
5660                 return 0;
5661         }
5662
5663         err = ipc_has_perm(&shp->shm_perm, perms);
5664         return err;
5665 }
5666
5667 static int selinux_shm_shmat(struct shmid_kernel *shp,
5668                              char __user *shmaddr, int shmflg)
5669 {
5670         u32 perms;
5671
5672         if (shmflg & SHM_RDONLY)
5673                 perms = SHM__READ;
5674         else
5675                 perms = SHM__READ | SHM__WRITE;
5676
5677         return ipc_has_perm(&shp->shm_perm, perms);
5678 }
5679
5680 /* Semaphore security operations */
5681 static int selinux_sem_alloc_security(struct sem_array *sma)
5682 {
5683         struct ipc_security_struct *isec;
5684         struct common_audit_data ad;
5685         u32 sid = current_sid();
5686         int rc;
5687
5688         rc = ipc_alloc_security(current, &sma->sem_perm, SECCLASS_SEM);
5689         if (rc)
5690                 return rc;
5691
5692         isec = sma->sem_perm.security;
5693
5694         ad.type = LSM_AUDIT_DATA_IPC;
5695         ad.u.ipc_id = sma->sem_perm.key;
5696
5697         rc = avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5698                           SEM__CREATE, &ad);
5699         if (rc) {
5700                 ipc_free_security(&sma->sem_perm);
5701                 return rc;
5702         }
5703         return 0;
5704 }
5705
5706 static void selinux_sem_free_security(struct sem_array *sma)
5707 {
5708         ipc_free_security(&sma->sem_perm);
5709 }
5710
5711 static int selinux_sem_associate(struct sem_array *sma, int semflg)
5712 {
5713         struct ipc_security_struct *isec;
5714         struct common_audit_data ad;
5715         u32 sid = current_sid();
5716
5717         isec = sma->sem_perm.security;
5718
5719         ad.type = LSM_AUDIT_DATA_IPC;
5720         ad.u.ipc_id = sma->sem_perm.key;
5721
5722         return avc_has_perm(sid, isec->sid, SECCLASS_SEM,
5723                             SEM__ASSOCIATE, &ad);
5724 }
5725
5726 /* Note, at this point, sma is locked down */
5727 static int selinux_sem_semctl(struct sem_array *sma, int cmd)
5728 {
5729         int err;
5730         u32 perms;
5731
5732         switch (cmd) {
5733         case IPC_INFO:
5734         case SEM_INFO:
5735                 /* No specific object, just general system-wide information. */
5736                 return task_has_system(current, SYSTEM__IPC_INFO);
5737         case GETPID:
5738         case GETNCNT:
5739         case GETZCNT:
5740                 perms = SEM__GETATTR;
5741                 break;
5742         case GETVAL:
5743         case GETALL:
5744                 perms = SEM__READ;
5745                 break;
5746         case SETVAL:
5747         case SETALL:
5748                 perms = SEM__WRITE;
5749                 break;
5750         case IPC_RMID:
5751                 perms = SEM__DESTROY;
5752                 break;
5753         case IPC_SET:
5754                 perms = SEM__SETATTR;
5755                 break;
5756         case IPC_STAT:
5757         case SEM_STAT:
5758                 perms = SEM__GETATTR | SEM__ASSOCIATE;
5759                 break;
5760         default:
5761                 return 0;
5762         }
5763
5764         err = ipc_has_perm(&sma->sem_perm, perms);
5765         return err;
5766 }
5767
5768 static int selinux_sem_semop(struct sem_array *sma,
5769                              struct sembuf *sops, unsigned nsops, int alter)
5770 {
5771         u32 perms;
5772
5773         if (alter)
5774                 perms = SEM__READ | SEM__WRITE;
5775         else
5776                 perms = SEM__READ;
5777
5778         return ipc_has_perm(&sma->sem_perm, perms);
5779 }
5780
5781 static int selinux_ipc_permission(struct kern_ipc_perm *ipcp, short flag)
5782 {
5783         u32 av = 0;
5784
5785         av = 0;
5786         if (flag & S_IRUGO)
5787                 av |= IPC__UNIX_READ;
5788         if (flag & S_IWUGO)
5789                 av |= IPC__UNIX_WRITE;
5790
5791         if (av == 0)
5792                 return 0;
5793
5794         return ipc_has_perm(ipcp, av);
5795 }
5796
5797 static void selinux_ipc_getsecid(struct kern_ipc_perm *ipcp, u32 *secid)
5798 {
5799         struct ipc_security_struct *isec = ipcp->security;
5800         *secid = isec->sid;
5801 }
5802
5803 static void selinux_d_instantiate(struct dentry *dentry, struct inode *inode)
5804 {
5805         if (inode)
5806                 inode_doinit_with_dentry(inode, dentry);
5807 }
5808
5809 static int selinux_getprocattr(struct task_struct *p,
5810                                char *name, char **value)
5811 {
5812         const struct task_security_struct *__tsec;
5813         u32 sid;
5814         int error;
5815         unsigned len;
5816
5817         if (current != p) {
5818                 error = current_has_perm(p, PROCESS__GETATTR);
5819                 if (error)
5820                         return error;
5821         }
5822
5823         rcu_read_lock();
5824         __tsec = __task_cred(p)->security;
5825
5826         if (!strcmp(name, "current"))
5827                 sid = __tsec->sid;
5828         else if (!strcmp(name, "prev"))
5829                 sid = __tsec->osid;
5830         else if (!strcmp(name, "exec"))
5831                 sid = __tsec->exec_sid;
5832         else if (!strcmp(name, "fscreate"))
5833                 sid = __tsec->create_sid;
5834         else if (!strcmp(name, "keycreate"))
5835                 sid = __tsec->keycreate_sid;
5836         else if (!strcmp(name, "sockcreate"))
5837                 sid = __tsec->sockcreate_sid;
5838         else
5839                 goto invalid;
5840         rcu_read_unlock();
5841
5842         if (!sid)
5843                 return 0;
5844
5845         error = security_sid_to_context(sid, value, &len);
5846         if (error)
5847                 return error;
5848         return len;
5849
5850 invalid:
5851         rcu_read_unlock();
5852         return -EINVAL;
5853 }
5854
5855 static int selinux_setprocattr(struct task_struct *p,
5856                                char *name, void *value, size_t size)
5857 {
5858         struct task_security_struct *tsec;
5859         struct cred *new;
5860         u32 sid = 0, ptsid;
5861         int error;
5862         char *str = value;
5863
5864         if (current != p) {
5865                 /* SELinux only allows a process to change its own
5866                    security attributes. */
5867                 return -EACCES;
5868         }
5869
5870         /*
5871          * Basic control over ability to set these attributes at all.
5872          * current == p, but we'll pass them separately in case the
5873          * above restriction is ever removed.
5874          */
5875         if (!strcmp(name, "exec"))
5876                 error = current_has_perm(p, PROCESS__SETEXEC);
5877         else if (!strcmp(name, "fscreate"))
5878                 error = current_has_perm(p, PROCESS__SETFSCREATE);
5879         else if (!strcmp(name, "keycreate"))
5880                 error = current_has_perm(p, PROCESS__SETKEYCREATE);
5881         else if (!strcmp(name, "sockcreate"))
5882                 error = current_has_perm(p, PROCESS__SETSOCKCREATE);
5883         else if (!strcmp(name, "current"))
5884                 error = current_has_perm(p, PROCESS__SETCURRENT);
5885         else
5886                 error = -EINVAL;
5887         if (error)
5888                 return error;
5889
5890         /* Obtain a SID for the context, if one was specified. */
5891         if (size && str[0] && str[0] != '\n') {
5892                 if (str[size-1] == '\n') {
5893                         str[size-1] = 0;
5894                         size--;
5895                 }
5896                 error = security_context_to_sid(value, size, &sid, GFP_KERNEL);
5897                 if (error == -EINVAL && !strcmp(name, "fscreate")) {
5898                         if (!capable(CAP_MAC_ADMIN)) {
5899                                 struct audit_buffer *ab;
5900                                 size_t audit_size;
5901
5902                                 /* We strip a nul only if it is at the end, otherwise the
5903                                  * context contains a nul and we should audit that */
5904                                 if (str[size - 1] == '\0')
5905                                         audit_size = size - 1;
5906                                 else
5907                                         audit_size = size;
5908                                 ab = audit_log_start(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR);
5909                                 audit_log_format(ab, "op=fscreate invalid_context=");
5910                                 audit_log_n_untrustedstring(ab, value, audit_size);
5911                                 audit_log_end(ab);
5912
5913                                 return error;
5914                         }
5915                         error = security_context_to_sid_force(value, size,
5916                                                               &sid);
5917                 }
5918                 if (error)
5919                         return error;
5920         }
5921
5922         new = prepare_creds();
5923         if (!new)
5924                 return -ENOMEM;
5925
5926         /* Permission checking based on the specified context is
5927            performed during the actual operation (execve,
5928            open/mkdir/...), when we know the full context of the
5929            operation.  See selinux_bprm_set_creds for the execve
5930            checks and may_create for the file creation checks. The
5931            operation will then fail if the context is not permitted. */
5932         tsec = new->security;
5933         if (!strcmp(name, "exec")) {
5934                 tsec->exec_sid = sid;
5935         } else if (!strcmp(name, "fscreate")) {
5936                 tsec->create_sid = sid;
5937         } else if (!strcmp(name, "keycreate")) {
5938                 error = may_create_key(sid, p);
5939                 if (error)
5940                         goto abort_change;
5941                 tsec->keycreate_sid = sid;
5942         } else if (!strcmp(name, "sockcreate")) {
5943                 tsec->sockcreate_sid = sid;
5944         } else if (!strcmp(name, "current")) {
5945                 error = -EINVAL;
5946                 if (sid == 0)
5947                         goto abort_change;
5948
5949                 /* Only allow single threaded processes to change context */
5950                 error = -EPERM;
5951                 if (!current_is_single_threaded()) {
5952                         error = security_bounded_transition(tsec->sid, sid);
5953                         if (error)
5954                                 goto abort_change;
5955                 }
5956
5957                 /* Check permissions for the transition. */
5958                 error = avc_has_perm(tsec->sid, sid, SECCLASS_PROCESS,
5959                                      PROCESS__DYNTRANSITION, NULL);
5960                 if (error)
5961                         goto abort_change;
5962
5963                 /* Check for ptracing, and update the task SID if ok.
5964                    Otherwise, leave SID unchanged and fail. */
5965                 ptsid = ptrace_parent_sid(p);
5966                 if (ptsid != 0) {
5967                         error = avc_has_perm(ptsid, sid, SECCLASS_PROCESS,
5968                                              PROCESS__PTRACE, NULL);
5969                         if (error)
5970                                 goto abort_change;
5971                 }
5972
5973                 tsec->sid = sid;
5974         } else {
5975                 error = -EINVAL;
5976                 goto abort_change;
5977         }
5978
5979         commit_creds(new);
5980         return size;
5981
5982 abort_change:
5983         abort_creds(new);
5984         return error;
5985 }
5986
5987 static int selinux_ismaclabel(const char *name)
5988 {
5989         return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0);
5990 }
5991
5992 static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen)
5993 {
5994         return security_sid_to_context(secid, secdata, seclen);
5995 }
5996
5997 static int selinux_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid)
5998 {
5999         return security_context_to_sid(secdata, seclen, secid, GFP_KERNEL);
6000 }
6001
6002 static void selinux_release_secctx(char *secdata, u32 seclen)
6003 {
6004         kfree(secdata);
6005 }
6006
6007 static void selinux_inode_invalidate_secctx(struct inode *inode)
6008 {
6009         struct inode_security_struct *isec = inode->i_security;
6010
6011         spin_lock(&isec->lock);
6012         isec->initialized = LABEL_INVALID;
6013         spin_unlock(&isec->lock);
6014 }
6015
6016 /*
6017  *      called with inode->i_mutex locked
6018  */
6019 static int selinux_inode_notifysecctx(struct inode *inode, void *ctx, u32 ctxlen)
6020 {
6021         return selinux_inode_setsecurity(inode, XATTR_SELINUX_SUFFIX, ctx, ctxlen, 0);
6022 }
6023
6024 /*
6025  *      called with inode->i_mutex locked
6026  */
6027 static int selinux_inode_setsecctx(struct dentry *dentry, void *ctx, u32 ctxlen)
6028 {
6029         return __vfs_setxattr_noperm(dentry, XATTR_NAME_SELINUX, ctx, ctxlen, 0);
6030 }
6031
6032 static int selinux_inode_getsecctx(struct inode *inode, void **ctx, u32 *ctxlen)
6033 {
6034         int len = 0;
6035         len = selinux_inode_getsecurity(inode, XATTR_SELINUX_SUFFIX,
6036                                                 ctx, true);
6037         if (len < 0)
6038                 return len;
6039         *ctxlen = len;
6040         return 0;
6041 }
6042 #ifdef CONFIG_KEYS
6043
6044 static int selinux_key_alloc(struct key *k, const struct cred *cred,
6045                              unsigned long flags)
6046 {
6047         const struct task_security_struct *tsec;
6048         struct key_security_struct *ksec;
6049
6050         ksec = kzalloc(sizeof(struct key_security_struct), GFP_KERNEL);
6051         if (!ksec)
6052                 return -ENOMEM;
6053
6054         tsec = cred->security;
6055         if (tsec->keycreate_sid)
6056                 ksec->sid = tsec->keycreate_sid;
6057         else
6058                 ksec->sid = tsec->sid;
6059
6060         k->security = ksec;
6061         return 0;
6062 }
6063
6064 static void selinux_key_free(struct key *k)
6065 {
6066         struct key_security_struct *ksec = k->security;
6067
6068         k->security = NULL;
6069         kfree(ksec);
6070 }
6071
6072 static int selinux_key_permission(key_ref_t key_ref,
6073                                   const struct cred *cred,
6074                                   unsigned perm)
6075 {
6076         struct key *key;
6077         struct key_security_struct *ksec;
6078         u32 sid;
6079
6080         /* if no specific permissions are requested, we skip the
6081            permission check. No serious, additional covert channels
6082            appear to be created. */
6083         if (perm == 0)
6084                 return 0;
6085
6086         sid = cred_sid(cred);
6087
6088         key = key_ref_to_ptr(key_ref);
6089         ksec = key->security;
6090
6091         return avc_has_perm(sid, ksec->sid, SECCLASS_KEY, perm, NULL);
6092 }
6093
6094 static int selinux_key_getsecurity(struct key *key, char **_buffer)
6095 {
6096         struct key_security_struct *ksec = key->security;
6097         char *context = NULL;
6098         unsigned len;
6099         int rc;
6100
6101         rc = security_sid_to_context(ksec->sid, &context, &len);
6102         if (!rc)
6103                 rc = len;
6104         *_buffer = context;
6105         return rc;
6106 }
6107
6108 #endif
6109
6110 static struct security_hook_list selinux_hooks[] = {
6111         LSM_HOOK_INIT(binder_set_context_mgr, selinux_binder_set_context_mgr),
6112         LSM_HOOK_INIT(binder_transaction, selinux_binder_transaction),
6113         LSM_HOOK_INIT(binder_transfer_binder, selinux_binder_transfer_binder),
6114         LSM_HOOK_INIT(binder_transfer_file, selinux_binder_transfer_file),
6115
6116         LSM_HOOK_INIT(ptrace_access_check, selinux_ptrace_access_check),
6117         LSM_HOOK_INIT(ptrace_traceme, selinux_ptrace_traceme),
6118         LSM_HOOK_INIT(capget, selinux_capget),
6119         LSM_HOOK_INIT(capset, selinux_capset),
6120         LSM_HOOK_INIT(capable, selinux_capable),
6121         LSM_HOOK_INIT(quotactl, selinux_quotactl),
6122         LSM_HOOK_INIT(quota_on, selinux_quota_on),
6123         LSM_HOOK_INIT(syslog, selinux_syslog),
6124         LSM_HOOK_INIT(vm_enough_memory, selinux_vm_enough_memory),
6125
6126         LSM_HOOK_INIT(netlink_send, selinux_netlink_send),
6127
6128         LSM_HOOK_INIT(bprm_set_creds, selinux_bprm_set_creds),
6129         LSM_HOOK_INIT(bprm_committing_creds, selinux_bprm_committing_creds),
6130         LSM_HOOK_INIT(bprm_committed_creds, selinux_bprm_committed_creds),
6131         LSM_HOOK_INIT(bprm_secureexec, selinux_bprm_secureexec),
6132
6133         LSM_HOOK_INIT(sb_alloc_security, selinux_sb_alloc_security),
6134         LSM_HOOK_INIT(sb_free_security, selinux_sb_free_security),
6135         LSM_HOOK_INIT(sb_copy_data, selinux_sb_copy_data),
6136         LSM_HOOK_INIT(sb_remount, selinux_sb_remount),
6137         LSM_HOOK_INIT(sb_kern_mount, selinux_sb_kern_mount),
6138         LSM_HOOK_INIT(sb_show_options, selinux_sb_show_options),
6139         LSM_HOOK_INIT(sb_statfs, selinux_sb_statfs),
6140         LSM_HOOK_INIT(sb_mount, selinux_mount),
6141         LSM_HOOK_INIT(sb_umount, selinux_umount),
6142         LSM_HOOK_INIT(sb_set_mnt_opts, selinux_set_mnt_opts),
6143         LSM_HOOK_INIT(sb_clone_mnt_opts, selinux_sb_clone_mnt_opts),
6144         LSM_HOOK_INIT(sb_parse_opts_str, selinux_parse_opts_str),
6145
6146         LSM_HOOK_INIT(dentry_init_security, selinux_dentry_init_security),
6147         LSM_HOOK_INIT(dentry_create_files_as, selinux_dentry_create_files_as),
6148
6149         LSM_HOOK_INIT(inode_alloc_security, selinux_inode_alloc_security),
6150         LSM_HOOK_INIT(inode_free_security, selinux_inode_free_security),
6151         LSM_HOOK_INIT(inode_init_security, selinux_inode_init_security),
6152         LSM_HOOK_INIT(inode_create, selinux_inode_create),
6153         LSM_HOOK_INIT(inode_link, selinux_inode_link),
6154         LSM_HOOK_INIT(inode_unlink, selinux_inode_unlink),
6155         LSM_HOOK_INIT(inode_symlink, selinux_inode_symlink),
6156         LSM_HOOK_INIT(inode_mkdir, selinux_inode_mkdir),
6157         LSM_HOOK_INIT(inode_rmdir, selinux_inode_rmdir),
6158         LSM_HOOK_INIT(inode_mknod, selinux_inode_mknod),
6159         LSM_HOOK_INIT(inode_rename, selinux_inode_rename),
6160         LSM_HOOK_INIT(inode_readlink, selinux_inode_readlink),
6161         LSM_HOOK_INIT(inode_follow_link, selinux_inode_follow_link),
6162         LSM_HOOK_INIT(inode_permission, selinux_inode_permission),
6163         LSM_HOOK_INIT(inode_setattr, selinux_inode_setattr),
6164         LSM_HOOK_INIT(inode_getattr, selinux_inode_getattr),
6165         LSM_HOOK_INIT(inode_setxattr, selinux_inode_setxattr),
6166         LSM_HOOK_INIT(inode_post_setxattr, selinux_inode_post_setxattr),
6167         LSM_HOOK_INIT(inode_getxattr, selinux_inode_getxattr),
6168         LSM_HOOK_INIT(inode_listxattr, selinux_inode_listxattr),
6169         LSM_HOOK_INIT(inode_removexattr, selinux_inode_removexattr),
6170         LSM_HOOK_INIT(inode_getsecurity, selinux_inode_getsecurity),
6171         LSM_HOOK_INIT(inode_setsecurity, selinux_inode_setsecurity),
6172         LSM_HOOK_INIT(inode_listsecurity, selinux_inode_listsecurity),
6173         LSM_HOOK_INIT(inode_getsecid, selinux_inode_getsecid),
6174         LSM_HOOK_INIT(inode_copy_up, selinux_inode_copy_up),
6175         LSM_HOOK_INIT(inode_copy_up_xattr, selinux_inode_copy_up_xattr),
6176
6177         LSM_HOOK_INIT(file_permission, selinux_file_permission),
6178         LSM_HOOK_INIT(file_alloc_security, selinux_file_alloc_security),
6179         LSM_HOOK_INIT(file_free_security, selinux_file_free_security),
6180         LSM_HOOK_INIT(file_ioctl, selinux_file_ioctl),
6181         LSM_HOOK_INIT(mmap_file, selinux_mmap_file),
6182         LSM_HOOK_INIT(mmap_addr, selinux_mmap_addr),
6183         LSM_HOOK_INIT(file_mprotect, selinux_file_mprotect),
6184         LSM_HOOK_INIT(file_lock, selinux_file_lock),
6185         LSM_HOOK_INIT(file_fcntl, selinux_file_fcntl),
6186         LSM_HOOK_INIT(file_set_fowner, selinux_file_set_fowner),
6187         LSM_HOOK_INIT(file_send_sigiotask, selinux_file_send_sigiotask),
6188         LSM_HOOK_INIT(file_receive, selinux_file_receive),
6189
6190         LSM_HOOK_INIT(file_open, selinux_file_open),
6191
6192         LSM_HOOK_INIT(task_create, selinux_task_create),
6193         LSM_HOOK_INIT(cred_alloc_blank, selinux_cred_alloc_blank),
6194         LSM_HOOK_INIT(cred_free, selinux_cred_free),
6195         LSM_HOOK_INIT(cred_prepare, selinux_cred_prepare),
6196         LSM_HOOK_INIT(cred_transfer, selinux_cred_transfer),
6197         LSM_HOOK_INIT(kernel_act_as, selinux_kernel_act_as),
6198         LSM_HOOK_INIT(kernel_create_files_as, selinux_kernel_create_files_as),
6199         LSM_HOOK_INIT(kernel_module_request, selinux_kernel_module_request),
6200         LSM_HOOK_INIT(kernel_read_file, selinux_kernel_read_file),
6201         LSM_HOOK_INIT(task_setpgid, selinux_task_setpgid),
6202         LSM_HOOK_INIT(task_getpgid, selinux_task_getpgid),
6203         LSM_HOOK_INIT(task_getsid, selinux_task_getsid),
6204         LSM_HOOK_INIT(task_getsecid, selinux_task_getsecid),
6205         LSM_HOOK_INIT(task_setnice, selinux_task_setnice),
6206         LSM_HOOK_INIT(task_setioprio, selinux_task_setioprio),
6207         LSM_HOOK_INIT(task_getioprio, selinux_task_getioprio),
6208         LSM_HOOK_INIT(task_setrlimit, selinux_task_setrlimit),
6209         LSM_HOOK_INIT(task_setscheduler, selinux_task_setscheduler),
6210         LSM_HOOK_INIT(task_getscheduler, selinux_task_getscheduler),
6211         LSM_HOOK_INIT(task_movememory, selinux_task_movememory),
6212         LSM_HOOK_INIT(task_kill, selinux_task_kill),
6213         LSM_HOOK_INIT(task_wait, selinux_task_wait),
6214         LSM_HOOK_INIT(task_to_inode, selinux_task_to_inode),
6215
6216         LSM_HOOK_INIT(ipc_permission, selinux_ipc_permission),
6217         LSM_HOOK_INIT(ipc_getsecid, selinux_ipc_getsecid),
6218
6219         LSM_HOOK_INIT(msg_msg_alloc_security, selinux_msg_msg_alloc_security),
6220         LSM_HOOK_INIT(msg_msg_free_security, selinux_msg_msg_free_security),
6221
6222         LSM_HOOK_INIT(msg_queue_alloc_security,
6223                         selinux_msg_queue_alloc_security),
6224         LSM_HOOK_INIT(msg_queue_free_security, selinux_msg_queue_free_security),
6225         LSM_HOOK_INIT(msg_queue_associate, selinux_msg_queue_associate),
6226         LSM_HOOK_INIT(msg_queue_msgctl, selinux_msg_queue_msgctl),
6227         LSM_HOOK_INIT(msg_queue_msgsnd, selinux_msg_queue_msgsnd),
6228         LSM_HOOK_INIT(msg_queue_msgrcv, selinux_msg_queue_msgrcv),
6229
6230         LSM_HOOK_INIT(shm_alloc_security, selinux_shm_alloc_security),
6231         LSM_HOOK_INIT(shm_free_security, selinux_shm_free_security),
6232         LSM_HOOK_INIT(shm_associate, selinux_shm_associate),
6233         LSM_HOOK_INIT(shm_shmctl, selinux_shm_shmctl),
6234         LSM_HOOK_INIT(shm_shmat, selinux_shm_shmat),
6235
6236         LSM_HOOK_INIT(sem_alloc_security, selinux_sem_alloc_security),
6237         LSM_HOOK_INIT(sem_free_security, selinux_sem_free_security),
6238         LSM_HOOK_INIT(sem_associate, selinux_sem_associate),
6239         LSM_HOOK_INIT(sem_semctl, selinux_sem_semctl),
6240         LSM_HOOK_INIT(sem_semop, selinux_sem_semop),
6241
6242         LSM_HOOK_INIT(d_instantiate, selinux_d_instantiate),
6243
6244         LSM_HOOK_INIT(getprocattr, selinux_getprocattr),
6245         LSM_HOOK_INIT(setprocattr, selinux_setprocattr),
6246
6247         LSM_HOOK_INIT(ismaclabel, selinux_ismaclabel),
6248         LSM_HOOK_INIT(secid_to_secctx, selinux_secid_to_secctx),
6249         LSM_HOOK_INIT(secctx_to_secid, selinux_secctx_to_secid),
6250         LSM_HOOK_INIT(release_secctx, selinux_release_secctx),
6251         LSM_HOOK_INIT(inode_invalidate_secctx, selinux_inode_invalidate_secctx),
6252         LSM_HOOK_INIT(inode_notifysecctx, selinux_inode_notifysecctx),
6253         LSM_HOOK_INIT(inode_setsecctx, selinux_inode_setsecctx),
6254         LSM_HOOK_INIT(inode_getsecctx, selinux_inode_getsecctx),
6255
6256         LSM_HOOK_INIT(unix_stream_connect, selinux_socket_unix_stream_connect),
6257         LSM_HOOK_INIT(unix_may_send, selinux_socket_unix_may_send),
6258
6259         LSM_HOOK_INIT(socket_create, selinux_socket_create),
6260         LSM_HOOK_INIT(socket_post_create, selinux_socket_post_create),
6261         LSM_HOOK_INIT(socket_bind, selinux_socket_bind),
6262         LSM_HOOK_INIT(socket_connect, selinux_socket_connect),
6263         LSM_HOOK_INIT(socket_listen, selinux_socket_listen),
6264         LSM_HOOK_INIT(socket_accept, selinux_socket_accept),
6265         LSM_HOOK_INIT(socket_sendmsg, selinux_socket_sendmsg),
6266         LSM_HOOK_INIT(socket_recvmsg, selinux_socket_recvmsg),
6267         LSM_HOOK_INIT(socket_getsockname, selinux_socket_getsockname),
6268         LSM_HOOK_INIT(socket_getpeername, selinux_socket_getpeername),
6269         LSM_HOOK_INIT(socket_getsockopt, selinux_socket_getsockopt),
6270         LSM_HOOK_INIT(socket_setsockopt, selinux_socket_setsockopt),
6271         LSM_HOOK_INIT(socket_shutdown, selinux_socket_shutdown),
6272         LSM_HOOK_INIT(socket_sock_rcv_skb, selinux_socket_sock_rcv_skb),
6273         LSM_HOOK_INIT(socket_getpeersec_stream,
6274                         selinux_socket_getpeersec_stream),
6275         LSM_HOOK_INIT(socket_getpeersec_dgram, selinux_socket_getpeersec_dgram),
6276         LSM_HOOK_INIT(sk_alloc_security, selinux_sk_alloc_security),
6277         LSM_HOOK_INIT(sk_free_security, selinux_sk_free_security),
6278         LSM_HOOK_INIT(sk_clone_security, selinux_sk_clone_security),
6279         LSM_HOOK_INIT(sk_getsecid, selinux_sk_getsecid),
6280         LSM_HOOK_INIT(sock_graft, selinux_sock_graft),
6281         LSM_HOOK_INIT(inet_conn_request, selinux_inet_conn_request),
6282         LSM_HOOK_INIT(inet_csk_clone, selinux_inet_csk_clone),
6283         LSM_HOOK_INIT(inet_conn_established, selinux_inet_conn_established),
6284         LSM_HOOK_INIT(secmark_relabel_packet, selinux_secmark_relabel_packet),
6285         LSM_HOOK_INIT(secmark_refcount_inc, selinux_secmark_refcount_inc),
6286         LSM_HOOK_INIT(secmark_refcount_dec, selinux_secmark_refcount_dec),
6287         LSM_HOOK_INIT(req_classify_flow, selinux_req_classify_flow),
6288         LSM_HOOK_INIT(tun_dev_alloc_security, selinux_tun_dev_alloc_security),
6289         LSM_HOOK_INIT(tun_dev_free_security, selinux_tun_dev_free_security),
6290         LSM_HOOK_INIT(tun_dev_create, selinux_tun_dev_create),
6291         LSM_HOOK_INIT(tun_dev_attach_queue, selinux_tun_dev_attach_queue),
6292         LSM_HOOK_INIT(tun_dev_attach, selinux_tun_dev_attach),
6293         LSM_HOOK_INIT(tun_dev_open, selinux_tun_dev_open),
6294
6295 #ifdef CONFIG_SECURITY_NETWORK_XFRM
6296         LSM_HOOK_INIT(xfrm_policy_alloc_security, selinux_xfrm_policy_alloc),
6297         LSM_HOOK_INIT(xfrm_policy_clone_security, selinux_xfrm_policy_clone),
6298         LSM_HOOK_INIT(xfrm_policy_free_security, selinux_xfrm_policy_free),
6299         LSM_HOOK_INIT(xfrm_policy_delete_security, selinux_xfrm_policy_delete),
6300         LSM_HOOK_INIT(xfrm_state_alloc, selinux_xfrm_state_alloc),
6301         LSM_HOOK_INIT(xfrm_state_alloc_acquire,
6302                         selinux_xfrm_state_alloc_acquire),
6303         LSM_HOOK_INIT(xfrm_state_free_security, selinux_xfrm_state_free),
6304         LSM_HOOK_INIT(xfrm_state_delete_security, selinux_xfrm_state_delete),
6305         LSM_HOOK_INIT(xfrm_policy_lookup, selinux_xfrm_policy_lookup),
6306         LSM_HOOK_INIT(xfrm_state_pol_flow_match,
6307                         selinux_xfrm_state_pol_flow_match),
6308         LSM_HOOK_INIT(xfrm_decode_session, selinux_xfrm_decode_session),
6309 #endif
6310
6311 #ifdef CONFIG_KEYS
6312         LSM_HOOK_INIT(key_alloc, selinux_key_alloc),
6313         LSM_HOOK_INIT(key_free, selinux_key_free),
6314         LSM_HOOK_INIT(key_permission, selinux_key_permission),
6315         LSM_HOOK_INIT(key_getsecurity, selinux_key_getsecurity),
6316 #endif
6317
6318 #ifdef CONFIG_AUDIT
6319         LSM_HOOK_INIT(audit_rule_init, selinux_audit_rule_init),
6320         LSM_HOOK_INIT(audit_rule_known, selinux_audit_rule_known),
6321         LSM_HOOK_INIT(audit_rule_match, selinux_audit_rule_match),
6322         LSM_HOOK_INIT(audit_rule_free, selinux_audit_rule_free),
6323 #endif
6324 };
6325
6326 static __init int selinux_init(void)
6327 {
6328         if (!security_module_enable("selinux")) {
6329                 selinux_enabled = 0;
6330                 return 0;
6331         }
6332
6333         if (!selinux_enabled) {
6334                 printk(KERN_INFO "SELinux:  Disabled at boot.\n");
6335                 return 0;
6336         }
6337
6338         printk(KERN_INFO "SELinux:  Initializing.\n");
6339
6340         /* Set the security state for the initial task. */
6341         cred_init_security();
6342
6343         default_noexec = !(VM_DATA_DEFAULT_FLAGS & VM_EXEC);
6344
6345         sel_inode_cache = kmem_cache_create("selinux_inode_security",
6346                                             sizeof(struct inode_security_struct),
6347                                             0, SLAB_PANIC, NULL);
6348         file_security_cache = kmem_cache_create("selinux_file_security",
6349                                             sizeof(struct file_security_struct),
6350                                             0, SLAB_PANIC, NULL);
6351         avc_init();
6352
6353         security_add_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
6354
6355         if (avc_add_callback(selinux_netcache_avc_callback, AVC_CALLBACK_RESET))
6356                 panic("SELinux: Unable to register AVC netcache callback\n");
6357
6358         if (selinux_enforcing)
6359                 printk(KERN_DEBUG "SELinux:  Starting in enforcing mode\n");
6360         else
6361                 printk(KERN_DEBUG "SELinux:  Starting in permissive mode\n");
6362
6363         return 0;
6364 }
6365
6366 static void delayed_superblock_init(struct super_block *sb, void *unused)
6367 {
6368         superblock_doinit(sb, NULL);
6369 }
6370
6371 void selinux_complete_init(void)
6372 {
6373         printk(KERN_DEBUG "SELinux:  Completing initialization.\n");
6374
6375         /* Set up any superblocks initialized prior to the policy load. */
6376         printk(KERN_DEBUG "SELinux:  Setting up existing superblocks.\n");
6377         iterate_supers(delayed_superblock_init, NULL);
6378 }
6379
6380 /* SELinux requires early initialization in order to label
6381    all processes and objects when they are created. */
6382 security_initcall(selinux_init);
6383
6384 #if defined(CONFIG_NETFILTER)
6385
6386 static struct nf_hook_ops selinux_nf_ops[] = {
6387         {
6388                 .hook =         selinux_ipv4_postroute,
6389                 .pf =           NFPROTO_IPV4,
6390                 .hooknum =      NF_INET_POST_ROUTING,
6391                 .priority =     NF_IP_PRI_SELINUX_LAST,
6392         },
6393         {
6394                 .hook =         selinux_ipv4_forward,
6395                 .pf =           NFPROTO_IPV4,
6396                 .hooknum =      NF_INET_FORWARD,
6397                 .priority =     NF_IP_PRI_SELINUX_FIRST,
6398         },
6399         {
6400                 .hook =         selinux_ipv4_output,
6401                 .pf =           NFPROTO_IPV4,
6402                 .hooknum =      NF_INET_LOCAL_OUT,
6403                 .priority =     NF_IP_PRI_SELINUX_FIRST,
6404         },
6405 #if IS_ENABLED(CONFIG_IPV6)
6406         {
6407                 .hook =         selinux_ipv6_postroute,
6408                 .pf =           NFPROTO_IPV6,
6409                 .hooknum =      NF_INET_POST_ROUTING,
6410                 .priority =     NF_IP6_PRI_SELINUX_LAST,
6411         },
6412         {
6413                 .hook =         selinux_ipv6_forward,
6414                 .pf =           NFPROTO_IPV6,
6415                 .hooknum =      NF_INET_FORWARD,
6416                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
6417         },
6418         {
6419                 .hook =         selinux_ipv6_output,
6420                 .pf =           NFPROTO_IPV6,
6421                 .hooknum =      NF_INET_LOCAL_OUT,
6422                 .priority =     NF_IP6_PRI_SELINUX_FIRST,
6423         },
6424 #endif  /* IPV6 */
6425 };
6426
6427 static int __init selinux_nf_ip_init(void)
6428 {
6429         int err;
6430
6431         if (!selinux_enabled)
6432                 return 0;
6433
6434         printk(KERN_DEBUG "SELinux:  Registering netfilter hooks\n");
6435
6436         err = nf_register_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops));
6437         if (err)
6438                 panic("SELinux: nf_register_hooks: error %d\n", err);
6439
6440         return 0;
6441 }
6442
6443 __initcall(selinux_nf_ip_init);
6444
6445 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
6446 static void selinux_nf_ip_exit(void)
6447 {
6448         printk(KERN_DEBUG "SELinux:  Unregistering netfilter hooks\n");
6449
6450         nf_unregister_hooks(selinux_nf_ops, ARRAY_SIZE(selinux_nf_ops));
6451 }
6452 #endif
6453
6454 #else /* CONFIG_NETFILTER */
6455
6456 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
6457 #define selinux_nf_ip_exit()
6458 #endif
6459
6460 #endif /* CONFIG_NETFILTER */
6461
6462 #ifdef CONFIG_SECURITY_SELINUX_DISABLE
6463 static int selinux_disabled;
6464
6465 int selinux_disable(void)
6466 {
6467         if (ss_initialized) {
6468                 /* Not permitted after initial policy load. */
6469                 return -EINVAL;
6470         }
6471
6472         if (selinux_disabled) {
6473                 /* Only do this once. */
6474                 return -EINVAL;
6475         }
6476
6477         printk(KERN_INFO "SELinux:  Disabled at runtime.\n");
6478
6479         selinux_disabled = 1;
6480         selinux_enabled = 0;
6481
6482         security_delete_hooks(selinux_hooks, ARRAY_SIZE(selinux_hooks));
6483
6484         /* Try to destroy the avc node cache */
6485         avc_disable();
6486
6487         /* Unregister netfilter hooks. */
6488         selinux_nf_ip_exit();
6489
6490         /* Unregister selinuxfs. */
6491         exit_sel_fs();
6492
6493         return 0;
6494 }
6495 #endif