1// SPDX-License-Identifier: GPL-2.0-or-later 2/* 3 * eCryptfs: Linux filesystem encryption layer 4 * 5 * Copyright (C) 1997-2003 Erez Zadok 6 * Copyright (C) 2001-2003 Stony Brook University 7 * Copyright (C) 2004-2007 International Business Machines Corp. 8 * Author(s): Michael A. Halcrow <mahalcro@us.ibm.com> 9 * Michael C. Thompson <mcthomps@us.ibm.com> 10 * Tyler Hicks <code@tyhicks.com> 11 */ 12 13#include <linux/dcache.h> 14#include <linux/file.h> 15#include <linux/module.h> 16#include <linux/namei.h> 17#include <linux/skbuff.h> 18#include <linux/mount.h> 19#include <linux/pagemap.h> 20#include <linux/key.h> 21#include <linux/parser.h> 22#include <linux/fs_stack.h> 23#include <linux/slab.h> 24#include <linux/magic.h> 25#include "ecryptfs_kernel.h" 26 27/* 28 * Module parameter that defines the ecryptfs_verbosity level. 29 */ 30int ecryptfs_verbosity = 0; 31 32module_param(ecryptfs_verbosity, int, 0); 33MODULE_PARM_DESC(ecryptfs_verbosity, 34 "Initial verbosity level (0 or 1; defaults to " 35 "0, which is Quiet)"); 36 37/* 38 * Module parameter that defines the number of message buffer elements 39 */ 40unsigned int ecryptfs_message_buf_len = ECRYPTFS_DEFAULT_MSG_CTX_ELEMS; 41 42module_param(ecryptfs_message_buf_len, uint, 0); 43MODULE_PARM_DESC(ecryptfs_message_buf_len, 44 "Number of message buffer elements"); 45 46/* 47 * Module parameter that defines the maximum guaranteed amount of time to wait 48 * for a response from ecryptfsd. The actual sleep time will be, more than 49 * likely, a small amount greater than this specified value, but only less if 50 * the message successfully arrives. 51 */ 52signed long ecryptfs_message_wait_timeout = ECRYPTFS_MAX_MSG_CTX_TTL / HZ; 53 54module_param(ecryptfs_message_wait_timeout, long, 0); 55MODULE_PARM_DESC(ecryptfs_message_wait_timeout, 56 "Maximum number of seconds that an operation will " 57 "sleep while waiting for a message response from " 58 "userspace"); 59 60/* 61 * Module parameter that is an estimate of the maximum number of users 62 * that will be concurrently using eCryptfs. Set this to the right 63 * value to balance performance and memory use. 64 */ 65unsigned int ecryptfs_number_of_users = ECRYPTFS_DEFAULT_NUM_USERS; 66 67module_param(ecryptfs_number_of_users, uint, 0); 68MODULE_PARM_DESC(ecryptfs_number_of_users, "An estimate of the number of " 69 "concurrent users of eCryptfs"); 70 71void __ecryptfs_printk(const char *fmt, ...) 72{ 73 va_list args; 74 va_start(args, fmt); 75 if (fmt[1] == '7') { /* KERN_DEBUG */ 76 if (ecryptfs_verbosity >= 1) 77 vprintk(fmt, args); 78 } else 79 vprintk(fmt, args); 80 va_end(args); 81} 82 83/* 84 * ecryptfs_init_lower_file 85 * @ecryptfs_dentry: Fully initialized eCryptfs dentry object, with 86 * the lower dentry and the lower mount set 87 * 88 * eCryptfs only ever keeps a single open file for every lower 89 * inode. All I/O operations to the lower inode occur through that 90 * file. When the first eCryptfs dentry that interposes with the first 91 * lower dentry for that inode is created, this function creates the 92 * lower file struct and associates it with the eCryptfs 93 * inode. When all eCryptfs files associated with the inode are released, the 94 * file is closed. 95 * 96 * The lower file will be opened with read/write permissions, if 97 * possible. Otherwise, it is opened read-only. 98 * 99 * This function does nothing if a lower file is already 100 * associated with the eCryptfs inode. 101 * 102 * Returns zero on success; non-zero otherwise 103 */ 104static int ecryptfs_init_lower_file(struct dentry *dentry, 105 struct file **lower_file) 106{ 107 const struct cred *cred = current_cred(); 108 const struct path *path = ecryptfs_dentry_to_lower_path(dentry); 109 int rc; 110 111 rc = ecryptfs_privileged_open(lower_file, path->dentry, path->mnt, 112 cred); 113 if (rc) { 114 printk(KERN_ERR "Error opening lower file " 115 "for lower_dentry [0x%p] and lower_mnt [0x%p]; " 116 "rc = [%d]\n", path->dentry, path->mnt, rc); 117 (*lower_file) = NULL; 118 } 119 return rc; 120} 121 122int ecryptfs_get_lower_file(struct dentry *dentry, struct inode *inode) 123{ 124 struct ecryptfs_inode_info *inode_info; 125 int count, rc = 0; 126 127 inode_info = ecryptfs_inode_to_private(inode); 128 mutex_lock(&inode_info->lower_file_mutex); 129 count = atomic_inc_return(&inode_info->lower_file_count); 130 if (WARN_ON_ONCE(count < 1)) 131 rc = -EINVAL; 132 else if (count == 1) { 133 rc = ecryptfs_init_lower_file(dentry, 134 &inode_info->lower_file); 135 if (rc) 136 atomic_set(&inode_info->lower_file_count, 0); 137 } 138 mutex_unlock(&inode_info->lower_file_mutex); 139 return rc; 140} 141 142void ecryptfs_put_lower_file(struct inode *inode) 143{ 144 struct ecryptfs_inode_info *inode_info; 145 146 inode_info = ecryptfs_inode_to_private(inode); 147 if (atomic_dec_and_mutex_lock(&inode_info->lower_file_count, 148 &inode_info->lower_file_mutex)) { 149 filemap_write_and_wait(inode->i_mapping); 150 fput(inode_info->lower_file); 151 inode_info->lower_file = NULL; 152 mutex_unlock(&inode_info->lower_file_mutex); 153 } 154} 155 156enum { ecryptfs_opt_sig, ecryptfs_opt_ecryptfs_sig, 157 ecryptfs_opt_cipher, ecryptfs_opt_ecryptfs_cipher, 158 ecryptfs_opt_ecryptfs_key_bytes, 159 ecryptfs_opt_passthrough, ecryptfs_opt_xattr_metadata, 160 ecryptfs_opt_encrypted_view, ecryptfs_opt_fnek_sig, 161 ecryptfs_opt_fn_cipher, ecryptfs_opt_fn_cipher_key_bytes, 162 ecryptfs_opt_unlink_sigs, ecryptfs_opt_mount_auth_tok_only, 163 ecryptfs_opt_check_dev_ruid, 164 ecryptfs_opt_err }; 165 166static const match_table_t tokens = { 167 {ecryptfs_opt_sig, "sig=%s"}, 168 {ecryptfs_opt_ecryptfs_sig, "ecryptfs_sig=%s"}, 169 {ecryptfs_opt_cipher, "cipher=%s"}, 170 {ecryptfs_opt_ecryptfs_cipher, "ecryptfs_cipher=%s"}, 171 {ecryptfs_opt_ecryptfs_key_bytes, "ecryptfs_key_bytes=%u"}, 172 {ecryptfs_opt_passthrough, "ecryptfs_passthrough"}, 173 {ecryptfs_opt_xattr_metadata, "ecryptfs_xattr_metadata"}, 174 {ecryptfs_opt_encrypted_view, "ecryptfs_encrypted_view"}, 175 {ecryptfs_opt_fnek_sig, "ecryptfs_fnek_sig=%s"}, 176 {ecryptfs_opt_fn_cipher, "ecryptfs_fn_cipher=%s"}, 177 {ecryptfs_opt_fn_cipher_key_bytes, "ecryptfs_fn_key_bytes=%u"}, 178 {ecryptfs_opt_unlink_sigs, "ecryptfs_unlink_sigs"}, 179 {ecryptfs_opt_mount_auth_tok_only, "ecryptfs_mount_auth_tok_only"}, 180 {ecryptfs_opt_check_dev_ruid, "ecryptfs_check_dev_ruid"}, 181 {ecryptfs_opt_err, NULL} 182}; 183 184static int ecryptfs_init_global_auth_toks( 185 struct ecryptfs_mount_crypt_stat *mount_crypt_stat) 186{ 187 struct ecryptfs_global_auth_tok *global_auth_tok; 188 struct ecryptfs_auth_tok *auth_tok; 189 int rc = 0; 190 191 list_for_each_entry(global_auth_tok, 192 &mount_crypt_stat->global_auth_tok_list, 193 mount_crypt_stat_list) { 194 rc = ecryptfs_keyring_auth_tok_for_sig( 195 &global_auth_tok->global_auth_tok_key, &auth_tok, 196 global_auth_tok->sig); 197 if (rc) { 198 printk(KERN_ERR "Could not find valid key in user " 199 "session keyring for sig specified in mount " 200 "option: [%s]\n", global_auth_tok->sig); 201 global_auth_tok->flags |= ECRYPTFS_AUTH_TOK_INVALID; 202 goto out; 203 } else { 204 global_auth_tok->flags &= ~ECRYPTFS_AUTH_TOK_INVALID; 205 up_write(&(global_auth_tok->global_auth_tok_key)->sem); 206 } 207 } 208out: 209 return rc; 210} 211 212static void ecryptfs_init_mount_crypt_stat( 213 struct ecryptfs_mount_crypt_stat *mount_crypt_stat) 214{ 215 memset((void *)mount_crypt_stat, 0, 216 sizeof(struct ecryptfs_mount_crypt_stat)); 217 INIT_LIST_HEAD(&mount_crypt_stat->global_auth_tok_list); 218 mutex_init(&mount_crypt_stat->global_auth_tok_list_mutex); 219 mount_crypt_stat->flags |= ECRYPTFS_MOUNT_CRYPT_STAT_INITIALIZED; 220} 221 222/** 223 * ecryptfs_parse_options 224 * @sbi: The ecryptfs super block 225 * @options: The options passed to the kernel 226 * @check_ruid: set to 1 if device uid should be checked against the ruid 227 * 228 * Parse mount options: 229 * debug=N - ecryptfs_verbosity level for debug output 230 * sig=XXX - description(signature) of the key to use 231 * 232 * Returns the dentry object of the lower-level (lower/interposed) 233 * directory; We want to mount our stackable file system on top of 234 * that lower directory. 235 * 236 * The signature of the key to use must be the description of a key 237 * already in the keyring. Mounting will fail if the key can not be 238 * found. 239 * 240 * Returns zero on success; non-zero on error 241 */ 242static int ecryptfs_parse_options(struct ecryptfs_sb_info *sbi, char *options, 243 uid_t *check_ruid) 244{ 245 char *p; 246 int rc = 0; 247 int sig_set = 0; 248 int cipher_name_set = 0; 249 int fn_cipher_name_set = 0; 250 int cipher_key_bytes; 251 int cipher_key_bytes_set = 0; 252 int fn_cipher_key_bytes; 253 int fn_cipher_key_bytes_set = 0; 254 struct ecryptfs_mount_crypt_stat *mount_crypt_stat = 255 &sbi->mount_crypt_stat; 256 substring_t args[MAX_OPT_ARGS]; 257 int token; 258 char *sig_src; 259 char *cipher_name_src; 260 char *fn_cipher_name_src; 261 char *fnek_src; 262 char *cipher_key_bytes_src; 263 char *fn_cipher_key_bytes_src; 264 u8 cipher_code; 265 266 *check_ruid = 0; 267 268 if (!options) { 269 rc = -EINVAL; 270 goto out; 271 } 272 ecryptfs_init_mount_crypt_stat(mount_crypt_stat); 273 while ((p = strsep(&options, ",")) != NULL) { 274 if (!*p) 275 continue; 276 token = match_token(p, tokens, args); 277 switch (token) { 278 case ecryptfs_opt_sig: 279 case ecryptfs_opt_ecryptfs_sig: 280 sig_src = args[0].from; 281 rc = ecryptfs_add_global_auth_tok(mount_crypt_stat, 282 sig_src, 0); 283 if (rc) { 284 printk(KERN_ERR "Error attempting to register " 285 "global sig; rc = [%d]\n", rc); 286 goto out; 287 } 288 sig_set = 1; 289 break; 290 case ecryptfs_opt_cipher: 291 case ecryptfs_opt_ecryptfs_cipher: 292 cipher_name_src = args[0].from; 293 strscpy(mount_crypt_stat->global_default_cipher_name, 294 cipher_name_src); 295 cipher_name_set = 1; 296 break; 297 case ecryptfs_opt_ecryptfs_key_bytes: 298 cipher_key_bytes_src = args[0].from; 299 cipher_key_bytes = 300 (int)simple_strtol(cipher_key_bytes_src, 301 &cipher_key_bytes_src, 0); 302 mount_crypt_stat->global_default_cipher_key_size = 303 cipher_key_bytes; 304 cipher_key_bytes_set = 1; 305 break; 306 case ecryptfs_opt_passthrough: 307 mount_crypt_stat->flags |= 308 ECRYPTFS_PLAINTEXT_PASSTHROUGH_ENABLED; 309 break; 310 case ecryptfs_opt_xattr_metadata: 311 mount_crypt_stat->flags |= 312 ECRYPTFS_XATTR_METADATA_ENABLED; 313 break; 314 case ecryptfs_opt_encrypted_view: 315 mount_crypt_stat->flags |= 316 ECRYPTFS_XATTR_METADATA_ENABLED; 317 mount_crypt_stat->flags |= 318 ECRYPTFS_ENCRYPTED_VIEW_ENABLED; 319 break; 320 case ecryptfs_opt_fnek_sig: 321 fnek_src = args[0].from; 322 strscpy(mount_crypt_stat->global_default_fnek_sig, 323 fnek_src); 324 rc = ecryptfs_add_global_auth_tok( 325 mount_crypt_stat, 326 mount_crypt_stat->global_default_fnek_sig, 327 ECRYPTFS_AUTH_TOK_FNEK); 328 if (rc) { 329 printk(KERN_ERR "Error attempting to register " 330 "global fnek sig [%s]; rc = [%d]\n", 331 mount_crypt_stat->global_default_fnek_sig, 332 rc); 333 goto out; 334 } 335 mount_crypt_stat->flags |= 336 (ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES 337 | ECRYPTFS_GLOBAL_ENCFN_USE_MOUNT_FNEK); 338 break; 339 case ecryptfs_opt_fn_cipher: 340 fn_cipher_name_src = args[0].from; 341 strscpy(mount_crypt_stat->global_default_fn_cipher_name, 342 fn_cipher_name_src); 343 fn_cipher_name_set = 1; 344 break; 345 case ecryptfs_opt_fn_cipher_key_bytes: 346 fn_cipher_key_bytes_src = args[0].from; 347 fn_cipher_key_bytes = 348 (int)simple_strtol(fn_cipher_key_bytes_src, 349 &fn_cipher_key_bytes_src, 0); 350 mount_crypt_stat->global_default_fn_cipher_key_bytes = 351 fn_cipher_key_bytes; 352 fn_cipher_key_bytes_set = 1; 353 break; 354 case ecryptfs_opt_unlink_sigs: 355 mount_crypt_stat->flags |= ECRYPTFS_UNLINK_SIGS; 356 break; 357 case ecryptfs_opt_mount_auth_tok_only: 358 mount_crypt_stat->flags |= 359 ECRYPTFS_GLOBAL_MOUNT_AUTH_TOK_ONLY; 360 break; 361 case ecryptfs_opt_check_dev_ruid: 362 *check_ruid = 1; 363 break; 364 case ecryptfs_opt_err: 365 default: 366 printk(KERN_WARNING 367 "%s: eCryptfs: unrecognized option [%s]\n", 368 __func__, p); 369 } 370 } 371 if (!sig_set) { 372 rc = -EINVAL; 373 ecryptfs_printk(KERN_ERR, "You must supply at least one valid " 374 "auth tok signature as a mount " 375 "parameter; see the eCryptfs README\n"); 376 goto out; 377 } 378 if (!cipher_name_set) { 379 int cipher_name_len = strlen(ECRYPTFS_DEFAULT_CIPHER); 380 381 BUG_ON(cipher_name_len > ECRYPTFS_MAX_CIPHER_NAME_SIZE); 382 strcpy(mount_crypt_stat->global_default_cipher_name, 383 ECRYPTFS_DEFAULT_CIPHER); 384 } 385 if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) 386 && !fn_cipher_name_set) 387 strcpy(mount_crypt_stat->global_default_fn_cipher_name, 388 mount_crypt_stat->global_default_cipher_name); 389 if (!cipher_key_bytes_set) 390 mount_crypt_stat->global_default_cipher_key_size = 0; 391 if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) 392 && !fn_cipher_key_bytes_set) 393 mount_crypt_stat->global_default_fn_cipher_key_bytes = 394 mount_crypt_stat->global_default_cipher_key_size; 395 396 cipher_code = ecryptfs_code_for_cipher_string( 397 mount_crypt_stat->global_default_cipher_name, 398 mount_crypt_stat->global_default_cipher_key_size); 399 if (!cipher_code) { 400 ecryptfs_printk(KERN_ERR, 401 "eCryptfs doesn't support cipher: %s\n", 402 mount_crypt_stat->global_default_cipher_name); 403 rc = -EINVAL; 404 goto out; 405 } 406 407 mutex_lock(&key_tfm_list_mutex); 408 if (!ecryptfs_tfm_exists(mount_crypt_stat->global_default_cipher_name, 409 NULL)) { 410 rc = ecryptfs_add_new_key_tfm( 411 NULL, mount_crypt_stat->global_default_cipher_name, 412 mount_crypt_stat->global_default_cipher_key_size); 413 if (rc) { 414 printk(KERN_ERR "Error attempting to initialize " 415 "cipher with name = [%s] and key size = [%td]; " 416 "rc = [%d]\n", 417 mount_crypt_stat->global_default_cipher_name, 418 mount_crypt_stat->global_default_cipher_key_size, 419 rc); 420 rc = -EINVAL; 421 mutex_unlock(&key_tfm_list_mutex); 422 goto out; 423 } 424 } 425 if ((mount_crypt_stat->flags & ECRYPTFS_GLOBAL_ENCRYPT_FILENAMES) 426 && !ecryptfs_tfm_exists( 427 mount_crypt_stat->global_default_fn_cipher_name, NULL)) { 428 rc = ecryptfs_add_new_key_tfm( 429 NULL, mount_crypt_stat->global_default_fn_cipher_name, 430 mount_crypt_stat->global_default_fn_cipher_key_bytes); 431 if (rc) { 432 printk(KERN_ERR "Error attempting to initialize " 433 "cipher with name = [%s] and key size = [%td]; " 434 "rc = [%d]\n", 435 mount_crypt_stat->global_default_fn_cipher_name, 436 mount_crypt_stat->global_default_fn_cipher_key_bytes, 437 rc); 438 rc = -EINVAL; 439 mutex_unlock(&key_tfm_list_mutex); 440 goto out; 441 } 442 } 443 mutex_unlock(&key_tfm_list_mutex); 444 rc = ecryptfs_init_global_auth_toks(mount_crypt_stat); 445 if (rc) 446 printk(KERN_WARNING "One or more global auth toks could not " 447 "properly register; rc = [%d]\n", rc); 448out: 449 return rc; 450} 451 452struct kmem_cache *ecryptfs_sb_info_cache; 453static struct file_system_type ecryptfs_fs_type; 454 455/* 456 * ecryptfs_mount 457 * @fs_type: The filesystem type that the superblock should belong to 458 * @flags: The flags associated with the mount 459 * @dev_name: The path to mount over 460 * @raw_data: The options passed into the kernel 461 */ 462static struct dentry *ecryptfs_mount(struct file_system_type *fs_type, int flags, 463 const char *dev_name, void *raw_data) 464{ 465 struct super_block *s; 466 struct ecryptfs_sb_info *sbi; 467 struct ecryptfs_mount_crypt_stat *mount_crypt_stat; 468 struct ecryptfs_dentry_info *root_info; 469 const char *err = "Getting sb failed"; 470 struct inode *inode; 471 struct path path; 472 uid_t check_ruid; 473 int rc; 474 475 sbi = kmem_cache_zalloc(ecryptfs_sb_info_cache, GFP_KERNEL); 476 if (!sbi) { 477 rc = -ENOMEM; 478 goto out; 479 } 480 481 if (!dev_name) { 482 rc = -EINVAL; 483 err = "Device name cannot be null"; 484 goto out; 485 } 486 487 rc = ecryptfs_parse_options(sbi, raw_data, &check_ruid); 488 if (rc) { 489 err = "Error parsing options"; 490 goto out; 491 } 492 mount_crypt_stat = &sbi->mount_crypt_stat; 493 494 s = sget(fs_type, NULL, set_anon_super, flags, NULL); 495 if (IS_ERR(s)) { 496 rc = PTR_ERR(s); 497 goto out; 498 } 499 500 rc = super_setup_bdi(s); 501 if (rc) 502 goto out1; 503 504 ecryptfs_set_superblock_private(s, sbi); 505 506 /* ->kill_sb() will take care of sbi after that point */ 507 sbi = NULL; 508 s->s_op = &ecryptfs_sops; 509 s->s_xattr = ecryptfs_xattr_handlers; 510 s->s_d_op = &ecryptfs_dops; 511 512 err = "Reading sb failed"; 513 rc = kern_path(dev_name, LOOKUP_FOLLOW | LOOKUP_DIRECTORY, &path); 514 if (rc) { 515 ecryptfs_printk(KERN_WARNING, "kern_path() failed\n"); 516 goto out1; 517 } 518 if (path.dentry->d_sb->s_type == &ecryptfs_fs_type) { 519 rc = -EINVAL; 520 printk(KERN_ERR "Mount on filesystem of type " 521 "eCryptfs explicitly disallowed due to " 522 "known incompatibilities\n"); 523 goto out_free; 524 } 525 526 if (is_idmapped_mnt(path.mnt)) { 527 rc = -EINVAL; 528 printk(KERN_ERR "Mounting on idmapped mounts currently disallowed\n"); 529 goto out_free; 530 } 531 532 if (check_ruid && !uid_eq(d_inode(path.dentry)->i_uid, current_uid())) { 533 rc = -EPERM; 534 printk(KERN_ERR "Mount of device (uid: %d) not owned by " 535 "requested user (uid: %d)\n", 536 i_uid_read(d_inode(path.dentry)), 537 from_kuid(&init_user_ns, current_uid())); 538 goto out_free; 539 } 540 541 ecryptfs_set_superblock_lower(s, path.dentry->d_sb); 542 543 /** 544 * Set the POSIX ACL flag based on whether they're enabled in the lower 545 * mount. 546 */ 547 s->s_flags = flags & ~SB_POSIXACL; 548 s->s_flags |= path.dentry->d_sb->s_flags & SB_POSIXACL; 549 550 /** 551 * Force a read-only eCryptfs mount when: 552 * 1) The lower mount is ro 553 * 2) The ecryptfs_encrypted_view mount option is specified 554 */ 555 if (sb_rdonly(path.dentry->d_sb) || mount_crypt_stat->flags & ECRYPTFS_ENCRYPTED_VIEW_ENABLED) 556 s->s_flags |= SB_RDONLY; 557 558 s->s_maxbytes = path.dentry->d_sb->s_maxbytes; 559 s->s_blocksize = path.dentry->d_sb->s_blocksize; 560 s->s_magic = ECRYPTFS_SUPER_MAGIC; 561 s->s_stack_depth = path.dentry->d_sb->s_stack_depth + 1; 562 563 rc = -EINVAL; 564 if (s->s_stack_depth > FILESYSTEM_MAX_STACK_DEPTH) { 565 pr_err("eCryptfs: maximum fs stacking depth exceeded\n"); 566 goto out_free; 567 } 568 569 inode = ecryptfs_get_inode(d_inode(path.dentry), s); 570 rc = PTR_ERR(inode); 571 if (IS_ERR(inode)) 572 goto out_free; 573 574 s->s_root = d_make_root(inode); 575 if (!s->s_root) { 576 rc = -ENOMEM; 577 goto out_free; 578 } 579 580 rc = -ENOMEM; 581 root_info = kmem_cache_zalloc(ecryptfs_dentry_info_cache, GFP_KERNEL); 582 if (!root_info) 583 goto out_free; 584 585 /* ->kill_sb() will take care of root_info */ 586 ecryptfs_set_dentry_private(s->s_root, root_info); 587 root_info->lower_path = path; 588 589 s->s_flags |= SB_ACTIVE; 590 return dget(s->s_root); 591 592out_free: 593 path_put(&path); 594out1: 595 deactivate_locked_super(s); 596out: 597 if (sbi) { 598 ecryptfs_destroy_mount_crypt_stat(&sbi->mount_crypt_stat); 599 kmem_cache_free(ecryptfs_sb_info_cache, sbi); 600 } 601 printk(KERN_ERR "%s; rc = [%d]\n", err, rc); 602 return ERR_PTR(rc); 603} 604 605/** 606 * ecryptfs_kill_block_super 607 * @sb: The ecryptfs super block 608 * 609 * Used to bring the superblock down and free the private data. 610 */ 611static void ecryptfs_kill_block_super(struct super_block *sb) 612{ 613 struct ecryptfs_sb_info *sb_info = ecryptfs_superblock_to_private(sb); 614 kill_anon_super(sb); 615 if (!sb_info) 616 return; 617 ecryptfs_destroy_mount_crypt_stat(&sb_info->mount_crypt_stat); 618 kmem_cache_free(ecryptfs_sb_info_cache, sb_info); 619} 620 621static struct file_system_type ecryptfs_fs_type = { 622 .owner = THIS_MODULE, 623 .name = "ecryptfs", 624 .mount = ecryptfs_mount, 625 .kill_sb = ecryptfs_kill_block_super, 626 .fs_flags = 0 627}; 628MODULE_ALIAS_FS("ecryptfs"); 629 630/* 631 * inode_info_init_once 632 * 633 * Initializes the ecryptfs_inode_info_cache when it is created 634 */ 635static void 636inode_info_init_once(void *vptr) 637{ 638 struct ecryptfs_inode_info *ei = (struct ecryptfs_inode_info *)vptr; 639 640 inode_init_once(&ei->vfs_inode); 641} 642 643static struct ecryptfs_cache_info { 644 struct kmem_cache **cache; 645 const char *name; 646 size_t size; 647 slab_flags_t flags; 648 void (*ctor)(void *obj); 649} ecryptfs_cache_infos[] = { 650 { 651 .cache = &ecryptfs_auth_tok_list_item_cache, 652 .name = "ecryptfs_auth_tok_list_item", 653 .size = sizeof(struct ecryptfs_auth_tok_list_item), 654 }, 655 { 656 .cache = &ecryptfs_file_info_cache, 657 .name = "ecryptfs_file_cache", 658 .size = sizeof(struct ecryptfs_file_info), 659 }, 660 { 661 .cache = &ecryptfs_dentry_info_cache, 662 .name = "ecryptfs_dentry_info_cache", 663 .size = sizeof(struct ecryptfs_dentry_info), 664 }, 665 { 666 .cache = &ecryptfs_inode_info_cache, 667 .name = "ecryptfs_inode_cache", 668 .size = sizeof(struct ecryptfs_inode_info), 669 .flags = SLAB_ACCOUNT, 670 .ctor = inode_info_init_once, 671 }, 672 { 673 .cache = &ecryptfs_sb_info_cache, 674 .name = "ecryptfs_sb_cache", 675 .size = sizeof(struct ecryptfs_sb_info), 676 }, 677 { 678 .cache = &ecryptfs_header_cache, 679 .name = "ecryptfs_headers", 680 .size = PAGE_SIZE, 681 }, 682 { 683 .cache = &ecryptfs_xattr_cache, 684 .name = "ecryptfs_xattr_cache", 685 .size = PAGE_SIZE, 686 }, 687 { 688 .cache = &ecryptfs_key_record_cache, 689 .name = "ecryptfs_key_record_cache", 690 .size = sizeof(struct ecryptfs_key_record), 691 }, 692 { 693 .cache = &ecryptfs_key_sig_cache, 694 .name = "ecryptfs_key_sig_cache", 695 .size = sizeof(struct ecryptfs_key_sig), 696 }, 697 { 698 .cache = &ecryptfs_global_auth_tok_cache, 699 .name = "ecryptfs_global_auth_tok_cache", 700 .size = sizeof(struct ecryptfs_global_auth_tok), 701 }, 702 { 703 .cache = &ecryptfs_key_tfm_cache, 704 .name = "ecryptfs_key_tfm_cache", 705 .size = sizeof(struct ecryptfs_key_tfm), 706 }, 707}; 708 709static void ecryptfs_free_kmem_caches(void) 710{ 711 int i; 712 713 /* 714 * Make sure all delayed rcu free inodes are flushed before we 715 * destroy cache. 716 */ 717 rcu_barrier(); 718 719 for (i = 0; i < ARRAY_SIZE(ecryptfs_cache_infos); i++) { 720 struct ecryptfs_cache_info *info; 721 722 info = &ecryptfs_cache_infos[i]; 723 kmem_cache_destroy(*(info->cache)); 724 } 725} 726 727/** 728 * ecryptfs_init_kmem_caches 729 * 730 * Returns zero on success; non-zero otherwise 731 */ 732static int ecryptfs_init_kmem_caches(void) 733{ 734 int i; 735 736 for (i = 0; i < ARRAY_SIZE(ecryptfs_cache_infos); i++) { 737 struct ecryptfs_cache_info *info; 738 739 info = &ecryptfs_cache_infos[i]; 740 *(info->cache) = kmem_cache_create(info->name, info->size, 0, 741 SLAB_HWCACHE_ALIGN | info->flags, info->ctor); 742 if (!*(info->cache)) { 743 ecryptfs_free_kmem_caches(); 744 ecryptfs_printk(KERN_WARNING, "%s: " 745 "kmem_cache_create failed\n", 746 info->name); 747 return -ENOMEM; 748 } 749 } 750 return 0; 751} 752 753static struct kobject *ecryptfs_kobj; 754 755static ssize_t version_show(struct kobject *kobj, 756 struct kobj_attribute *attr, char *buff) 757{ 758 return snprintf(buff, PAGE_SIZE, "%d\n", ECRYPTFS_VERSIONING_MASK); 759} 760 761static struct kobj_attribute version_attr = __ATTR_RO(version); 762 763static struct attribute *attributes[] = { 764 &version_attr.attr, 765 NULL, 766}; 767 768static const struct attribute_group attr_group = { 769 .attrs = attributes, 770}; 771 772static int do_sysfs_registration(void) 773{ 774 int rc; 775 776 ecryptfs_kobj = kobject_create_and_add("ecryptfs", fs_kobj); 777 if (!ecryptfs_kobj) { 778 printk(KERN_ERR "Unable to create ecryptfs kset\n"); 779 rc = -ENOMEM; 780 goto out; 781 } 782 rc = sysfs_create_group(ecryptfs_kobj, &attr_group); 783 if (rc) { 784 printk(KERN_ERR 785 "Unable to create ecryptfs version attributes\n"); 786 kobject_put(ecryptfs_kobj); 787 } 788out: 789 return rc; 790} 791 792static void do_sysfs_unregistration(void) 793{ 794 sysfs_remove_group(ecryptfs_kobj, &attr_group); 795 kobject_put(ecryptfs_kobj); 796} 797 798static int __init ecryptfs_init(void) 799{ 800 int rc; 801 802 if (ECRYPTFS_DEFAULT_EXTENT_SIZE > PAGE_SIZE) { 803 rc = -EINVAL; 804 ecryptfs_printk(KERN_ERR, "The eCryptfs extent size is " 805 "larger than the host's page size, and so " 806 "eCryptfs cannot run on this system. The " 807 "default eCryptfs extent size is [%u] bytes; " 808 "the page size is [%lu] bytes.\n", 809 ECRYPTFS_DEFAULT_EXTENT_SIZE, 810 (unsigned long)PAGE_SIZE); 811 goto out; 812 } 813 rc = ecryptfs_init_kmem_caches(); 814 if (rc) { 815 printk(KERN_ERR 816 "Failed to allocate one or more kmem_cache objects\n"); 817 goto out; 818 } 819 rc = do_sysfs_registration(); 820 if (rc) { 821 printk(KERN_ERR "sysfs registration failed\n"); 822 goto out_free_kmem_caches; 823 } 824 rc = ecryptfs_init_kthread(); 825 if (rc) { 826 printk(KERN_ERR "%s: kthread initialization failed; " 827 "rc = [%d]\n", __func__, rc); 828 goto out_do_sysfs_unregistration; 829 } 830 rc = ecryptfs_init_messaging(); 831 if (rc) { 832 printk(KERN_ERR "Failure occurred while attempting to " 833 "initialize the communications channel to " 834 "ecryptfsd\n"); 835 goto out_destroy_kthread; 836 } 837 rc = ecryptfs_init_crypto(); 838 if (rc) { 839 printk(KERN_ERR "Failure whilst attempting to init crypto; " 840 "rc = [%d]\n", rc); 841 goto out_release_messaging; 842 } 843 rc = register_filesystem(&ecryptfs_fs_type); 844 if (rc) { 845 printk(KERN_ERR "Failed to register filesystem\n"); 846 goto out_destroy_crypto; 847 } 848 if (ecryptfs_verbosity > 0) 849 printk(KERN_CRIT "eCryptfs verbosity set to %d. Secret values " 850 "will be written to the syslog!\n", ecryptfs_verbosity); 851 852 goto out; 853out_destroy_crypto: 854 ecryptfs_destroy_crypto(); 855out_release_messaging: 856 ecryptfs_release_messaging(); 857out_destroy_kthread: 858 ecryptfs_destroy_kthread(); 859out_do_sysfs_unregistration: 860 do_sysfs_unregistration(); 861out_free_kmem_caches: 862 ecryptfs_free_kmem_caches(); 863out: 864 return rc; 865} 866 867static void __exit ecryptfs_exit(void) 868{ 869 int rc; 870 871 rc = ecryptfs_destroy_crypto(); 872 if (rc) 873 printk(KERN_ERR "Failure whilst attempting to destroy crypto; " 874 "rc = [%d]\n", rc); 875 ecryptfs_release_messaging(); 876 ecryptfs_destroy_kthread(); 877 do_sysfs_unregistration(); 878 unregister_filesystem(&ecryptfs_fs_type); 879 ecryptfs_free_kmem_caches(); 880} 881 882MODULE_AUTHOR("Michael A. Halcrow <mhalcrow@us.ibm.com>"); 883MODULE_DESCRIPTION("eCryptfs"); 884 885MODULE_LICENSE("GPL"); 886 887module_init(ecryptfs_init) 888module_exit(ecryptfs_exit) 889