1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2003 Jana Saout <jana@saout.de> 4 * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org> 5 * Copyright (C) 2006-2020 Red Hat, Inc. All rights reserved. 6 * Copyright (C) 2013-2020 Milan Broz <gmazyland@gmail.com> 7 * 8 * This file is released under the GPL. 9 */ 10 11 #include <linux/completion.h> 12 #include <linux/err.h> 13 #include <linux/module.h> 14 #include <linux/init.h> 15 #include <linux/kernel.h> 16 #include <linux/key.h> 17 #include <linux/bio.h> 18 #include <linux/blkdev.h> 19 #include <linux/blk-integrity.h> 20 #include <linux/mempool.h> 21 #include <linux/slab.h> 22 #include <linux/crypto.h> 23 #include <linux/workqueue.h> 24 #include <linux/kthread.h> 25 #include <linux/backing-dev.h> 26 #include <linux/atomic.h> 27 #include <linux/scatterlist.h> 28 #include <linux/rbtree.h> 29 #include <linux/ctype.h> 30 #include <asm/page.h> 31 #include <asm/unaligned.h> 32 #include <crypto/hash.h> 33 #include <crypto/md5.h> 34 #include <crypto/skcipher.h> 35 #include <crypto/aead.h> 36 #include <crypto/authenc.h> 37 #include <crypto/utils.h> 38 #include <linux/rtnetlink.h> /* for struct rtattr and RTA macros only */ 39 #include <linux/key-type.h> 40 #include <keys/user-type.h> 41 #include <keys/encrypted-type.h> 42 #include <keys/trusted-type.h> 43 44 #include <linux/device-mapper.h> 45 46 #include "dm-audit.h" 47 48 #define DM_MSG_PREFIX "crypt" 49 50 /* 51 * context holding the current state of a multi-part conversion 52 */ 53 struct convert_context { 54 struct completion restart; 55 struct bio *bio_in; 56 struct bvec_iter iter_in; 57 struct bio *bio_out; 58 struct bvec_iter iter_out; 59 atomic_t cc_pending; 60 u64 cc_sector; 61 union { 62 struct skcipher_request *req; 63 struct aead_request *req_aead; 64 } r; 65 bool aead_recheck; 66 bool aead_failed; 67 68 }; 69 70 /* 71 * per bio private data 72 */ 73 struct dm_crypt_io { 74 struct crypt_config *cc; 75 struct bio *base_bio; 76 u8 *integrity_metadata; 77 bool integrity_metadata_from_pool:1; 78 79 struct work_struct work; 80 81 struct convert_context ctx; 82 83 atomic_t io_pending; 84 blk_status_t error; 85 sector_t sector; 86 87 struct bvec_iter saved_bi_iter; 88 89 struct rb_node rb_node; 90 } CRYPTO_MINALIGN_ATTR; 91 92 struct dm_crypt_request { 93 struct convert_context *ctx; 94 struct scatterlist sg_in[4]; 95 struct scatterlist sg_out[4]; 96 u64 iv_sector; 97 }; 98 99 struct crypt_config; 100 101 struct crypt_iv_operations { 102 int (*ctr)(struct crypt_config *cc, struct dm_target *ti, 103 const char *opts); 104 void (*dtr)(struct crypt_config *cc); 105 int (*init)(struct crypt_config *cc); 106 int (*wipe)(struct crypt_config *cc); 107 int (*generator)(struct crypt_config *cc, u8 *iv, 108 struct dm_crypt_request *dmreq); 109 int (*post)(struct crypt_config *cc, u8 *iv, 110 struct dm_crypt_request *dmreq); 111 }; 112 113 struct iv_benbi_private { 114 int shift; 115 }; 116 117 #define LMK_SEED_SIZE 64 /* hash + 0 */ 118 struct iv_lmk_private { 119 struct crypto_shash *hash_tfm; 120 u8 *seed; 121 }; 122 123 #define TCW_WHITENING_SIZE 16 124 struct iv_tcw_private { 125 struct crypto_shash *crc32_tfm; 126 u8 *iv_seed; 127 u8 *whitening; 128 }; 129 130 #define ELEPHANT_MAX_KEY_SIZE 32 131 struct iv_elephant_private { 132 struct crypto_skcipher *tfm; 133 }; 134 135 /* 136 * Crypt: maps a linear range of a block device 137 * and encrypts / decrypts at the same time. 138 */ 139 enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID, 140 DM_CRYPT_SAME_CPU, DM_CRYPT_NO_OFFLOAD, 141 DM_CRYPT_NO_READ_WORKQUEUE, DM_CRYPT_NO_WRITE_WORKQUEUE, 142 DM_CRYPT_WRITE_INLINE }; 143 144 enum cipher_flags { 145 CRYPT_MODE_INTEGRITY_AEAD, /* Use authenticated mode for cipher */ 146 CRYPT_IV_LARGE_SECTORS, /* Calculate IV from sector_size, not 512B sectors */ 147 CRYPT_ENCRYPT_PREPROCESS, /* Must preprocess data for encryption (elephant) */ 148 }; 149 150 /* 151 * The fields in here must be read only after initialization. 152 */ 153 struct crypt_config { 154 struct dm_dev *dev; 155 sector_t start; 156 157 struct percpu_counter n_allocated_pages; 158 159 struct workqueue_struct *io_queue; 160 struct workqueue_struct *crypt_queue; 161 162 spinlock_t write_thread_lock; 163 struct task_struct *write_thread; 164 struct rb_root write_tree; 165 166 char *cipher_string; 167 char *cipher_auth; 168 char *key_string; 169 170 const struct crypt_iv_operations *iv_gen_ops; 171 union { 172 struct iv_benbi_private benbi; 173 struct iv_lmk_private lmk; 174 struct iv_tcw_private tcw; 175 struct iv_elephant_private elephant; 176 } iv_gen_private; 177 u64 iv_offset; 178 unsigned int iv_size; 179 unsigned short sector_size; 180 unsigned char sector_shift; 181 182 union { 183 struct crypto_skcipher **tfms; 184 struct crypto_aead **tfms_aead; 185 } cipher_tfm; 186 unsigned int tfms_count; 187 unsigned long cipher_flags; 188 189 /* 190 * Layout of each crypto request: 191 * 192 * struct skcipher_request 193 * context 194 * padding 195 * struct dm_crypt_request 196 * padding 197 * IV 198 * 199 * The padding is added so that dm_crypt_request and the IV are 200 * correctly aligned. 201 */ 202 unsigned int dmreq_start; 203 204 unsigned int per_bio_data_size; 205 206 unsigned long flags; 207 unsigned int key_size; 208 unsigned int key_parts; /* independent parts in key buffer */ 209 unsigned int key_extra_size; /* additional keys length */ 210 unsigned int key_mac_size; /* MAC key size for authenc(...) */ 211 212 unsigned int integrity_tag_size; 213 unsigned int integrity_iv_size; 214 unsigned int on_disk_tag_size; 215 216 /* 217 * pool for per bio private data, crypto requests, 218 * encryption requeusts/buffer pages and integrity tags 219 */ 220 unsigned int tag_pool_max_sectors; 221 mempool_t tag_pool; 222 mempool_t req_pool; 223 mempool_t page_pool; 224 225 struct bio_set bs; 226 struct mutex bio_alloc_lock; 227 228 u8 *authenc_key; /* space for keys in authenc() format (if used) */ 229 u8 key[] __counted_by(key_size); 230 }; 231 232 #define MIN_IOS 64 233 #define MAX_TAG_SIZE 480 234 #define POOL_ENTRY_SIZE 512 235 236 static DEFINE_SPINLOCK(dm_crypt_clients_lock); 237 static unsigned int dm_crypt_clients_n; 238 static volatile unsigned long dm_crypt_pages_per_client; 239 #define DM_CRYPT_MEMORY_PERCENT 2 240 #define DM_CRYPT_MIN_PAGES_PER_CLIENT (BIO_MAX_VECS * 16) 241 242 static void crypt_endio(struct bio *clone); 243 static void kcryptd_queue_crypt(struct dm_crypt_io *io); 244 static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 245 struct scatterlist *sg); 246 247 static bool crypt_integrity_aead(struct crypt_config *cc); 248 249 /* 250 * Use this to access cipher attributes that are independent of the key. 251 */ 252 static struct crypto_skcipher *any_tfm(struct crypt_config *cc) 253 { 254 return cc->cipher_tfm.tfms[0]; 255 } 256 257 static struct crypto_aead *any_tfm_aead(struct crypt_config *cc) 258 { 259 return cc->cipher_tfm.tfms_aead[0]; 260 } 261 262 /* 263 * Different IV generation algorithms: 264 * 265 * plain: the initial vector is the 32-bit little-endian version of the sector 266 * number, padded with zeros if necessary. 267 * 268 * plain64: the initial vector is the 64-bit little-endian version of the sector 269 * number, padded with zeros if necessary. 270 * 271 * plain64be: the initial vector is the 64-bit big-endian version of the sector 272 * number, padded with zeros if necessary. 273 * 274 * essiv: "encrypted sector|salt initial vector", the sector number is 275 * encrypted with the bulk cipher using a salt as key. The salt 276 * should be derived from the bulk cipher's key via hashing. 277 * 278 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 279 * (needed for LRW-32-AES and possible other narrow block modes) 280 * 281 * null: the initial vector is always zero. Provides compatibility with 282 * obsolete loop_fish2 devices. Do not use for new devices. 283 * 284 * lmk: Compatible implementation of the block chaining mode used 285 * by the Loop-AES block device encryption system 286 * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/ 287 * It operates on full 512 byte sectors and uses CBC 288 * with an IV derived from the sector number, the data and 289 * optionally extra IV seed. 290 * This means that after decryption the first block 291 * of sector must be tweaked according to decrypted data. 292 * Loop-AES can use three encryption schemes: 293 * version 1: is plain aes-cbc mode 294 * version 2: uses 64 multikey scheme with lmk IV generator 295 * version 3: the same as version 2 with additional IV seed 296 * (it uses 65 keys, last key is used as IV seed) 297 * 298 * tcw: Compatible implementation of the block chaining mode used 299 * by the TrueCrypt device encryption system (prior to version 4.1). 300 * For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat 301 * It operates on full 512 byte sectors and uses CBC 302 * with an IV derived from initial key and the sector number. 303 * In addition, whitening value is applied on every sector, whitening 304 * is calculated from initial key, sector number and mixed using CRC32. 305 * Note that this encryption scheme is vulnerable to watermarking attacks 306 * and should be used for old compatible containers access only. 307 * 308 * eboiv: Encrypted byte-offset IV (used in Bitlocker in CBC mode) 309 * The IV is encrypted little-endian byte-offset (with the same key 310 * and cipher as the volume). 311 * 312 * elephant: The extended version of eboiv with additional Elephant diffuser 313 * used with Bitlocker CBC mode. 314 * This mode was used in older Windows systems 315 * https://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf 316 */ 317 318 static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, 319 struct dm_crypt_request *dmreq) 320 { 321 memset(iv, 0, cc->iv_size); 322 *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff); 323 324 return 0; 325 } 326 327 static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv, 328 struct dm_crypt_request *dmreq) 329 { 330 memset(iv, 0, cc->iv_size); 331 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 332 333 return 0; 334 } 335 336 static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv, 337 struct dm_crypt_request *dmreq) 338 { 339 memset(iv, 0, cc->iv_size); 340 /* iv_size is at least of size u64; usually it is 16 bytes */ 341 *(__be64 *)&iv[cc->iv_size - sizeof(u64)] = cpu_to_be64(dmreq->iv_sector); 342 343 return 0; 344 } 345 346 static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, 347 struct dm_crypt_request *dmreq) 348 { 349 /* 350 * ESSIV encryption of the IV is now handled by the crypto API, 351 * so just pass the plain sector number here. 352 */ 353 memset(iv, 0, cc->iv_size); 354 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 355 356 return 0; 357 } 358 359 static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, 360 const char *opts) 361 { 362 unsigned int bs; 363 int log; 364 365 if (crypt_integrity_aead(cc)) 366 bs = crypto_aead_blocksize(any_tfm_aead(cc)); 367 else 368 bs = crypto_skcipher_blocksize(any_tfm(cc)); 369 log = ilog2(bs); 370 371 /* 372 * We need to calculate how far we must shift the sector count 373 * to get the cipher block count, we use this shift in _gen. 374 */ 375 if (1 << log != bs) { 376 ti->error = "cypher blocksize is not a power of 2"; 377 return -EINVAL; 378 } 379 380 if (log > 9) { 381 ti->error = "cypher blocksize is > 512"; 382 return -EINVAL; 383 } 384 385 cc->iv_gen_private.benbi.shift = 9 - log; 386 387 return 0; 388 } 389 390 static void crypt_iv_benbi_dtr(struct crypt_config *cc) 391 { 392 } 393 394 static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, 395 struct dm_crypt_request *dmreq) 396 { 397 __be64 val; 398 399 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ 400 401 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1); 402 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); 403 404 return 0; 405 } 406 407 static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, 408 struct dm_crypt_request *dmreq) 409 { 410 memset(iv, 0, cc->iv_size); 411 412 return 0; 413 } 414 415 static void crypt_iv_lmk_dtr(struct crypt_config *cc) 416 { 417 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 418 419 if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm)) 420 crypto_free_shash(lmk->hash_tfm); 421 lmk->hash_tfm = NULL; 422 423 kfree_sensitive(lmk->seed); 424 lmk->seed = NULL; 425 } 426 427 static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti, 428 const char *opts) 429 { 430 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 431 432 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 433 ti->error = "Unsupported sector size for LMK"; 434 return -EINVAL; 435 } 436 437 lmk->hash_tfm = crypto_alloc_shash("md5", 0, 438 CRYPTO_ALG_ALLOCATES_MEMORY); 439 if (IS_ERR(lmk->hash_tfm)) { 440 ti->error = "Error initializing LMK hash"; 441 return PTR_ERR(lmk->hash_tfm); 442 } 443 444 /* No seed in LMK version 2 */ 445 if (cc->key_parts == cc->tfms_count) { 446 lmk->seed = NULL; 447 return 0; 448 } 449 450 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL); 451 if (!lmk->seed) { 452 crypt_iv_lmk_dtr(cc); 453 ti->error = "Error kmallocing seed storage in LMK"; 454 return -ENOMEM; 455 } 456 457 return 0; 458 } 459 460 static int crypt_iv_lmk_init(struct crypt_config *cc) 461 { 462 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 463 int subkey_size = cc->key_size / cc->key_parts; 464 465 /* LMK seed is on the position of LMK_KEYS + 1 key */ 466 if (lmk->seed) 467 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size), 468 crypto_shash_digestsize(lmk->hash_tfm)); 469 470 return 0; 471 } 472 473 static int crypt_iv_lmk_wipe(struct crypt_config *cc) 474 { 475 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 476 477 if (lmk->seed) 478 memset(lmk->seed, 0, LMK_SEED_SIZE); 479 480 return 0; 481 } 482 483 static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv, 484 struct dm_crypt_request *dmreq, 485 u8 *data) 486 { 487 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 488 SHASH_DESC_ON_STACK(desc, lmk->hash_tfm); 489 struct md5_state md5state; 490 __le32 buf[4]; 491 int i, r; 492 493 desc->tfm = lmk->hash_tfm; 494 495 r = crypto_shash_init(desc); 496 if (r) 497 return r; 498 499 if (lmk->seed) { 500 r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE); 501 if (r) 502 return r; 503 } 504 505 /* Sector is always 512B, block size 16, add data of blocks 1-31 */ 506 r = crypto_shash_update(desc, data + 16, 16 * 31); 507 if (r) 508 return r; 509 510 /* Sector is cropped to 56 bits here */ 511 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF); 512 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000); 513 buf[2] = cpu_to_le32(4024); 514 buf[3] = 0; 515 r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf)); 516 if (r) 517 return r; 518 519 /* No MD5 padding here */ 520 r = crypto_shash_export(desc, &md5state); 521 if (r) 522 return r; 523 524 for (i = 0; i < MD5_HASH_WORDS; i++) 525 __cpu_to_le32s(&md5state.hash[i]); 526 memcpy(iv, &md5state.hash, cc->iv_size); 527 528 return 0; 529 } 530 531 static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv, 532 struct dm_crypt_request *dmreq) 533 { 534 struct scatterlist *sg; 535 u8 *src; 536 int r = 0; 537 538 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 539 sg = crypt_get_sg_data(cc, dmreq->sg_in); 540 src = kmap_local_page(sg_page(sg)); 541 r = crypt_iv_lmk_one(cc, iv, dmreq, src + sg->offset); 542 kunmap_local(src); 543 } else 544 memset(iv, 0, cc->iv_size); 545 546 return r; 547 } 548 549 static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv, 550 struct dm_crypt_request *dmreq) 551 { 552 struct scatterlist *sg; 553 u8 *dst; 554 int r; 555 556 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) 557 return 0; 558 559 sg = crypt_get_sg_data(cc, dmreq->sg_out); 560 dst = kmap_local_page(sg_page(sg)); 561 r = crypt_iv_lmk_one(cc, iv, dmreq, dst + sg->offset); 562 563 /* Tweak the first block of plaintext sector */ 564 if (!r) 565 crypto_xor(dst + sg->offset, iv, cc->iv_size); 566 567 kunmap_local(dst); 568 return r; 569 } 570 571 static void crypt_iv_tcw_dtr(struct crypt_config *cc) 572 { 573 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 574 575 kfree_sensitive(tcw->iv_seed); 576 tcw->iv_seed = NULL; 577 kfree_sensitive(tcw->whitening); 578 tcw->whitening = NULL; 579 580 if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm)) 581 crypto_free_shash(tcw->crc32_tfm); 582 tcw->crc32_tfm = NULL; 583 } 584 585 static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti, 586 const char *opts) 587 { 588 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 589 590 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 591 ti->error = "Unsupported sector size for TCW"; 592 return -EINVAL; 593 } 594 595 if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) { 596 ti->error = "Wrong key size for TCW"; 597 return -EINVAL; 598 } 599 600 tcw->crc32_tfm = crypto_alloc_shash("crc32", 0, 601 CRYPTO_ALG_ALLOCATES_MEMORY); 602 if (IS_ERR(tcw->crc32_tfm)) { 603 ti->error = "Error initializing CRC32 in TCW"; 604 return PTR_ERR(tcw->crc32_tfm); 605 } 606 607 tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL); 608 tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL); 609 if (!tcw->iv_seed || !tcw->whitening) { 610 crypt_iv_tcw_dtr(cc); 611 ti->error = "Error allocating seed storage in TCW"; 612 return -ENOMEM; 613 } 614 615 return 0; 616 } 617 618 static int crypt_iv_tcw_init(struct crypt_config *cc) 619 { 620 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 621 int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE; 622 623 memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size); 624 memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size], 625 TCW_WHITENING_SIZE); 626 627 return 0; 628 } 629 630 static int crypt_iv_tcw_wipe(struct crypt_config *cc) 631 { 632 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 633 634 memset(tcw->iv_seed, 0, cc->iv_size); 635 memset(tcw->whitening, 0, TCW_WHITENING_SIZE); 636 637 return 0; 638 } 639 640 static int crypt_iv_tcw_whitening(struct crypt_config *cc, 641 struct dm_crypt_request *dmreq, 642 u8 *data) 643 { 644 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 645 __le64 sector = cpu_to_le64(dmreq->iv_sector); 646 u8 buf[TCW_WHITENING_SIZE]; 647 SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm); 648 int i, r; 649 650 /* xor whitening with sector number */ 651 crypto_xor_cpy(buf, tcw->whitening, (u8 *)§or, 8); 652 crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)§or, 8); 653 654 /* calculate crc32 for every 32bit part and xor it */ 655 desc->tfm = tcw->crc32_tfm; 656 for (i = 0; i < 4; i++) { 657 r = crypto_shash_digest(desc, &buf[i * 4], 4, &buf[i * 4]); 658 if (r) 659 goto out; 660 } 661 crypto_xor(&buf[0], &buf[12], 4); 662 crypto_xor(&buf[4], &buf[8], 4); 663 664 /* apply whitening (8 bytes) to whole sector */ 665 for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++) 666 crypto_xor(data + i * 8, buf, 8); 667 out: 668 memzero_explicit(buf, sizeof(buf)); 669 return r; 670 } 671 672 static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv, 673 struct dm_crypt_request *dmreq) 674 { 675 struct scatterlist *sg; 676 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 677 __le64 sector = cpu_to_le64(dmreq->iv_sector); 678 u8 *src; 679 int r = 0; 680 681 /* Remove whitening from ciphertext */ 682 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 683 sg = crypt_get_sg_data(cc, dmreq->sg_in); 684 src = kmap_local_page(sg_page(sg)); 685 r = crypt_iv_tcw_whitening(cc, dmreq, src + sg->offset); 686 kunmap_local(src); 687 } 688 689 /* Calculate IV */ 690 crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)§or, 8); 691 if (cc->iv_size > 8) 692 crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)§or, 693 cc->iv_size - 8); 694 695 return r; 696 } 697 698 static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv, 699 struct dm_crypt_request *dmreq) 700 { 701 struct scatterlist *sg; 702 u8 *dst; 703 int r; 704 705 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 706 return 0; 707 708 /* Apply whitening on ciphertext */ 709 sg = crypt_get_sg_data(cc, dmreq->sg_out); 710 dst = kmap_local_page(sg_page(sg)); 711 r = crypt_iv_tcw_whitening(cc, dmreq, dst + sg->offset); 712 kunmap_local(dst); 713 714 return r; 715 } 716 717 static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv, 718 struct dm_crypt_request *dmreq) 719 { 720 /* Used only for writes, there must be an additional space to store IV */ 721 get_random_bytes(iv, cc->iv_size); 722 return 0; 723 } 724 725 static int crypt_iv_eboiv_ctr(struct crypt_config *cc, struct dm_target *ti, 726 const char *opts) 727 { 728 if (crypt_integrity_aead(cc)) { 729 ti->error = "AEAD transforms not supported for EBOIV"; 730 return -EINVAL; 731 } 732 733 if (crypto_skcipher_blocksize(any_tfm(cc)) != cc->iv_size) { 734 ti->error = "Block size of EBOIV cipher does not match IV size of block cipher"; 735 return -EINVAL; 736 } 737 738 return 0; 739 } 740 741 static int crypt_iv_eboiv_gen(struct crypt_config *cc, u8 *iv, 742 struct dm_crypt_request *dmreq) 743 { 744 struct crypto_skcipher *tfm = any_tfm(cc); 745 struct skcipher_request *req; 746 struct scatterlist src, dst; 747 DECLARE_CRYPTO_WAIT(wait); 748 unsigned int reqsize; 749 int err; 750 u8 *buf; 751 752 reqsize = sizeof(*req) + crypto_skcipher_reqsize(tfm); 753 reqsize = ALIGN(reqsize, __alignof__(__le64)); 754 755 req = kmalloc(reqsize + cc->iv_size, GFP_NOIO); 756 if (!req) 757 return -ENOMEM; 758 759 skcipher_request_set_tfm(req, tfm); 760 761 buf = (u8 *)req + reqsize; 762 memset(buf, 0, cc->iv_size); 763 *(__le64 *)buf = cpu_to_le64(dmreq->iv_sector * cc->sector_size); 764 765 sg_init_one(&src, page_address(ZERO_PAGE(0)), cc->iv_size); 766 sg_init_one(&dst, iv, cc->iv_size); 767 skcipher_request_set_crypt(req, &src, &dst, cc->iv_size, buf); 768 skcipher_request_set_callback(req, 0, crypto_req_done, &wait); 769 err = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 770 kfree_sensitive(req); 771 772 return err; 773 } 774 775 static void crypt_iv_elephant_dtr(struct crypt_config *cc) 776 { 777 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 778 779 crypto_free_skcipher(elephant->tfm); 780 elephant->tfm = NULL; 781 } 782 783 static int crypt_iv_elephant_ctr(struct crypt_config *cc, struct dm_target *ti, 784 const char *opts) 785 { 786 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 787 int r; 788 789 elephant->tfm = crypto_alloc_skcipher("ecb(aes)", 0, 790 CRYPTO_ALG_ALLOCATES_MEMORY); 791 if (IS_ERR(elephant->tfm)) { 792 r = PTR_ERR(elephant->tfm); 793 elephant->tfm = NULL; 794 return r; 795 } 796 797 r = crypt_iv_eboiv_ctr(cc, ti, NULL); 798 if (r) 799 crypt_iv_elephant_dtr(cc); 800 return r; 801 } 802 803 static void diffuser_disk_to_cpu(u32 *d, size_t n) 804 { 805 #ifndef __LITTLE_ENDIAN 806 int i; 807 808 for (i = 0; i < n; i++) 809 d[i] = le32_to_cpu((__le32)d[i]); 810 #endif 811 } 812 813 static void diffuser_cpu_to_disk(__le32 *d, size_t n) 814 { 815 #ifndef __LITTLE_ENDIAN 816 int i; 817 818 for (i = 0; i < n; i++) 819 d[i] = cpu_to_le32((u32)d[i]); 820 #endif 821 } 822 823 static void diffuser_a_decrypt(u32 *d, size_t n) 824 { 825 int i, i1, i2, i3; 826 827 for (i = 0; i < 5; i++) { 828 i1 = 0; 829 i2 = n - 2; 830 i3 = n - 5; 831 832 while (i1 < (n - 1)) { 833 d[i1] += d[i2] ^ (d[i3] << 9 | d[i3] >> 23); 834 i1++; i2++; i3++; 835 836 if (i3 >= n) 837 i3 -= n; 838 839 d[i1] += d[i2] ^ d[i3]; 840 i1++; i2++; i3++; 841 842 if (i2 >= n) 843 i2 -= n; 844 845 d[i1] += d[i2] ^ (d[i3] << 13 | d[i3] >> 19); 846 i1++; i2++; i3++; 847 848 d[i1] += d[i2] ^ d[i3]; 849 i1++; i2++; i3++; 850 } 851 } 852 } 853 854 static void diffuser_a_encrypt(u32 *d, size_t n) 855 { 856 int i, i1, i2, i3; 857 858 for (i = 0; i < 5; i++) { 859 i1 = n - 1; 860 i2 = n - 2 - 1; 861 i3 = n - 5 - 1; 862 863 while (i1 > 0) { 864 d[i1] -= d[i2] ^ d[i3]; 865 i1--; i2--; i3--; 866 867 d[i1] -= d[i2] ^ (d[i3] << 13 | d[i3] >> 19); 868 i1--; i2--; i3--; 869 870 if (i2 < 0) 871 i2 += n; 872 873 d[i1] -= d[i2] ^ d[i3]; 874 i1--; i2--; i3--; 875 876 if (i3 < 0) 877 i3 += n; 878 879 d[i1] -= d[i2] ^ (d[i3] << 9 | d[i3] >> 23); 880 i1--; i2--; i3--; 881 } 882 } 883 } 884 885 static void diffuser_b_decrypt(u32 *d, size_t n) 886 { 887 int i, i1, i2, i3; 888 889 for (i = 0; i < 3; i++) { 890 i1 = 0; 891 i2 = 2; 892 i3 = 5; 893 894 while (i1 < (n - 1)) { 895 d[i1] += d[i2] ^ d[i3]; 896 i1++; i2++; i3++; 897 898 d[i1] += d[i2] ^ (d[i3] << 10 | d[i3] >> 22); 899 i1++; i2++; i3++; 900 901 if (i2 >= n) 902 i2 -= n; 903 904 d[i1] += d[i2] ^ d[i3]; 905 i1++; i2++; i3++; 906 907 if (i3 >= n) 908 i3 -= n; 909 910 d[i1] += d[i2] ^ (d[i3] << 25 | d[i3] >> 7); 911 i1++; i2++; i3++; 912 } 913 } 914 } 915 916 static void diffuser_b_encrypt(u32 *d, size_t n) 917 { 918 int i, i1, i2, i3; 919 920 for (i = 0; i < 3; i++) { 921 i1 = n - 1; 922 i2 = 2 - 1; 923 i3 = 5 - 1; 924 925 while (i1 > 0) { 926 d[i1] -= d[i2] ^ (d[i3] << 25 | d[i3] >> 7); 927 i1--; i2--; i3--; 928 929 if (i3 < 0) 930 i3 += n; 931 932 d[i1] -= d[i2] ^ d[i3]; 933 i1--; i2--; i3--; 934 935 if (i2 < 0) 936 i2 += n; 937 938 d[i1] -= d[i2] ^ (d[i3] << 10 | d[i3] >> 22); 939 i1--; i2--; i3--; 940 941 d[i1] -= d[i2] ^ d[i3]; 942 i1--; i2--; i3--; 943 } 944 } 945 } 946 947 static int crypt_iv_elephant(struct crypt_config *cc, struct dm_crypt_request *dmreq) 948 { 949 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 950 u8 *es, *ks, *data, *data2, *data_offset; 951 struct skcipher_request *req; 952 struct scatterlist *sg, *sg2, src, dst; 953 DECLARE_CRYPTO_WAIT(wait); 954 int i, r; 955 956 req = skcipher_request_alloc(elephant->tfm, GFP_NOIO); 957 es = kzalloc(16, GFP_NOIO); /* Key for AES */ 958 ks = kzalloc(32, GFP_NOIO); /* Elephant sector key */ 959 960 if (!req || !es || !ks) { 961 r = -ENOMEM; 962 goto out; 963 } 964 965 *(__le64 *)es = cpu_to_le64(dmreq->iv_sector * cc->sector_size); 966 967 /* E(Ks, e(s)) */ 968 sg_init_one(&src, es, 16); 969 sg_init_one(&dst, ks, 16); 970 skcipher_request_set_crypt(req, &src, &dst, 16, NULL); 971 skcipher_request_set_callback(req, 0, crypto_req_done, &wait); 972 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 973 if (r) 974 goto out; 975 976 /* E(Ks, e'(s)) */ 977 es[15] = 0x80; 978 sg_init_one(&dst, &ks[16], 16); 979 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 980 if (r) 981 goto out; 982 983 sg = crypt_get_sg_data(cc, dmreq->sg_out); 984 data = kmap_local_page(sg_page(sg)); 985 data_offset = data + sg->offset; 986 987 /* Cannot modify original bio, copy to sg_out and apply Elephant to it */ 988 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 989 sg2 = crypt_get_sg_data(cc, dmreq->sg_in); 990 data2 = kmap_local_page(sg_page(sg2)); 991 memcpy(data_offset, data2 + sg2->offset, cc->sector_size); 992 kunmap_local(data2); 993 } 994 995 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 996 diffuser_disk_to_cpu((u32 *)data_offset, cc->sector_size / sizeof(u32)); 997 diffuser_b_decrypt((u32 *)data_offset, cc->sector_size / sizeof(u32)); 998 diffuser_a_decrypt((u32 *)data_offset, cc->sector_size / sizeof(u32)); 999 diffuser_cpu_to_disk((__le32 *)data_offset, cc->sector_size / sizeof(u32)); 1000 } 1001 1002 for (i = 0; i < (cc->sector_size / 32); i++) 1003 crypto_xor(data_offset + i * 32, ks, 32); 1004 1005 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 1006 diffuser_disk_to_cpu((u32 *)data_offset, cc->sector_size / sizeof(u32)); 1007 diffuser_a_encrypt((u32 *)data_offset, cc->sector_size / sizeof(u32)); 1008 diffuser_b_encrypt((u32 *)data_offset, cc->sector_size / sizeof(u32)); 1009 diffuser_cpu_to_disk((__le32 *)data_offset, cc->sector_size / sizeof(u32)); 1010 } 1011 1012 kunmap_local(data); 1013 out: 1014 kfree_sensitive(ks); 1015 kfree_sensitive(es); 1016 skcipher_request_free(req); 1017 return r; 1018 } 1019 1020 static int crypt_iv_elephant_gen(struct crypt_config *cc, u8 *iv, 1021 struct dm_crypt_request *dmreq) 1022 { 1023 int r; 1024 1025 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 1026 r = crypt_iv_elephant(cc, dmreq); 1027 if (r) 1028 return r; 1029 } 1030 1031 return crypt_iv_eboiv_gen(cc, iv, dmreq); 1032 } 1033 1034 static int crypt_iv_elephant_post(struct crypt_config *cc, u8 *iv, 1035 struct dm_crypt_request *dmreq) 1036 { 1037 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 1038 return crypt_iv_elephant(cc, dmreq); 1039 1040 return 0; 1041 } 1042 1043 static int crypt_iv_elephant_init(struct crypt_config *cc) 1044 { 1045 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 1046 int key_offset = cc->key_size - cc->key_extra_size; 1047 1048 return crypto_skcipher_setkey(elephant->tfm, &cc->key[key_offset], cc->key_extra_size); 1049 } 1050 1051 static int crypt_iv_elephant_wipe(struct crypt_config *cc) 1052 { 1053 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 1054 u8 key[ELEPHANT_MAX_KEY_SIZE]; 1055 1056 memset(key, 0, cc->key_extra_size); 1057 return crypto_skcipher_setkey(elephant->tfm, key, cc->key_extra_size); 1058 } 1059 1060 static const struct crypt_iv_operations crypt_iv_plain_ops = { 1061 .generator = crypt_iv_plain_gen 1062 }; 1063 1064 static const struct crypt_iv_operations crypt_iv_plain64_ops = { 1065 .generator = crypt_iv_plain64_gen 1066 }; 1067 1068 static const struct crypt_iv_operations crypt_iv_plain64be_ops = { 1069 .generator = crypt_iv_plain64be_gen 1070 }; 1071 1072 static const struct crypt_iv_operations crypt_iv_essiv_ops = { 1073 .generator = crypt_iv_essiv_gen 1074 }; 1075 1076 static const struct crypt_iv_operations crypt_iv_benbi_ops = { 1077 .ctr = crypt_iv_benbi_ctr, 1078 .dtr = crypt_iv_benbi_dtr, 1079 .generator = crypt_iv_benbi_gen 1080 }; 1081 1082 static const struct crypt_iv_operations crypt_iv_null_ops = { 1083 .generator = crypt_iv_null_gen 1084 }; 1085 1086 static const struct crypt_iv_operations crypt_iv_lmk_ops = { 1087 .ctr = crypt_iv_lmk_ctr, 1088 .dtr = crypt_iv_lmk_dtr, 1089 .init = crypt_iv_lmk_init, 1090 .wipe = crypt_iv_lmk_wipe, 1091 .generator = crypt_iv_lmk_gen, 1092 .post = crypt_iv_lmk_post 1093 }; 1094 1095 static const struct crypt_iv_operations crypt_iv_tcw_ops = { 1096 .ctr = crypt_iv_tcw_ctr, 1097 .dtr = crypt_iv_tcw_dtr, 1098 .init = crypt_iv_tcw_init, 1099 .wipe = crypt_iv_tcw_wipe, 1100 .generator = crypt_iv_tcw_gen, 1101 .post = crypt_iv_tcw_post 1102 }; 1103 1104 static const struct crypt_iv_operations crypt_iv_random_ops = { 1105 .generator = crypt_iv_random_gen 1106 }; 1107 1108 static const struct crypt_iv_operations crypt_iv_eboiv_ops = { 1109 .ctr = crypt_iv_eboiv_ctr, 1110 .generator = crypt_iv_eboiv_gen 1111 }; 1112 1113 static const struct crypt_iv_operations crypt_iv_elephant_ops = { 1114 .ctr = crypt_iv_elephant_ctr, 1115 .dtr = crypt_iv_elephant_dtr, 1116 .init = crypt_iv_elephant_init, 1117 .wipe = crypt_iv_elephant_wipe, 1118 .generator = crypt_iv_elephant_gen, 1119 .post = crypt_iv_elephant_post 1120 }; 1121 1122 /* 1123 * Integrity extensions 1124 */ 1125 static bool crypt_integrity_aead(struct crypt_config *cc) 1126 { 1127 return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 1128 } 1129 1130 static bool crypt_integrity_hmac(struct crypt_config *cc) 1131 { 1132 return crypt_integrity_aead(cc) && cc->key_mac_size; 1133 } 1134 1135 /* Get sg containing data */ 1136 static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 1137 struct scatterlist *sg) 1138 { 1139 if (unlikely(crypt_integrity_aead(cc))) 1140 return &sg[2]; 1141 1142 return sg; 1143 } 1144 1145 static int dm_crypt_integrity_io_alloc(struct dm_crypt_io *io, struct bio *bio) 1146 { 1147 struct bio_integrity_payload *bip; 1148 unsigned int tag_len; 1149 int ret; 1150 1151 if (!bio_sectors(bio) || !io->cc->on_disk_tag_size) 1152 return 0; 1153 1154 bip = bio_integrity_alloc(bio, GFP_NOIO, 1); 1155 if (IS_ERR(bip)) 1156 return PTR_ERR(bip); 1157 1158 tag_len = io->cc->on_disk_tag_size * (bio_sectors(bio) >> io->cc->sector_shift); 1159 1160 bip->bip_iter.bi_sector = io->cc->start + io->sector; 1161 1162 ret = bio_integrity_add_page(bio, virt_to_page(io->integrity_metadata), 1163 tag_len, offset_in_page(io->integrity_metadata)); 1164 if (unlikely(ret != tag_len)) 1165 return -ENOMEM; 1166 1167 return 0; 1168 } 1169 1170 static int crypt_integrity_ctr(struct crypt_config *cc, struct dm_target *ti) 1171 { 1172 #ifdef CONFIG_BLK_DEV_INTEGRITY 1173 struct blk_integrity *bi = blk_get_integrity(cc->dev->bdev->bd_disk); 1174 struct mapped_device *md = dm_table_get_md(ti->table); 1175 1176 /* From now we require underlying device with our integrity profile */ 1177 if (!bi || strcasecmp(bi->profile->name, "DM-DIF-EXT-TAG")) { 1178 ti->error = "Integrity profile not supported."; 1179 return -EINVAL; 1180 } 1181 1182 if (bi->tag_size != cc->on_disk_tag_size || 1183 bi->tuple_size != cc->on_disk_tag_size) { 1184 ti->error = "Integrity profile tag size mismatch."; 1185 return -EINVAL; 1186 } 1187 if (1 << bi->interval_exp != cc->sector_size) { 1188 ti->error = "Integrity profile sector size mismatch."; 1189 return -EINVAL; 1190 } 1191 1192 if (crypt_integrity_aead(cc)) { 1193 cc->integrity_tag_size = cc->on_disk_tag_size - cc->integrity_iv_size; 1194 DMDEBUG("%s: Integrity AEAD, tag size %u, IV size %u.", dm_device_name(md), 1195 cc->integrity_tag_size, cc->integrity_iv_size); 1196 1197 if (crypto_aead_setauthsize(any_tfm_aead(cc), cc->integrity_tag_size)) { 1198 ti->error = "Integrity AEAD auth tag size is not supported."; 1199 return -EINVAL; 1200 } 1201 } else if (cc->integrity_iv_size) 1202 DMDEBUG("%s: Additional per-sector space %u bytes for IV.", dm_device_name(md), 1203 cc->integrity_iv_size); 1204 1205 if ((cc->integrity_tag_size + cc->integrity_iv_size) != bi->tag_size) { 1206 ti->error = "Not enough space for integrity tag in the profile."; 1207 return -EINVAL; 1208 } 1209 1210 return 0; 1211 #else 1212 ti->error = "Integrity profile not supported."; 1213 return -EINVAL; 1214 #endif 1215 } 1216 1217 static void crypt_convert_init(struct crypt_config *cc, 1218 struct convert_context *ctx, 1219 struct bio *bio_out, struct bio *bio_in, 1220 sector_t sector) 1221 { 1222 ctx->bio_in = bio_in; 1223 ctx->bio_out = bio_out; 1224 if (bio_in) 1225 ctx->iter_in = bio_in->bi_iter; 1226 if (bio_out) 1227 ctx->iter_out = bio_out->bi_iter; 1228 ctx->cc_sector = sector + cc->iv_offset; 1229 init_completion(&ctx->restart); 1230 } 1231 1232 static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc, 1233 void *req) 1234 { 1235 return (struct dm_crypt_request *)((char *)req + cc->dmreq_start); 1236 } 1237 1238 static void *req_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq) 1239 { 1240 return (void *)((char *)dmreq - cc->dmreq_start); 1241 } 1242 1243 static u8 *iv_of_dmreq(struct crypt_config *cc, 1244 struct dm_crypt_request *dmreq) 1245 { 1246 if (crypt_integrity_aead(cc)) 1247 return (u8 *)ALIGN((unsigned long)(dmreq + 1), 1248 crypto_aead_alignmask(any_tfm_aead(cc)) + 1); 1249 else 1250 return (u8 *)ALIGN((unsigned long)(dmreq + 1), 1251 crypto_skcipher_alignmask(any_tfm(cc)) + 1); 1252 } 1253 1254 static u8 *org_iv_of_dmreq(struct crypt_config *cc, 1255 struct dm_crypt_request *dmreq) 1256 { 1257 return iv_of_dmreq(cc, dmreq) + cc->iv_size; 1258 } 1259 1260 static __le64 *org_sector_of_dmreq(struct crypt_config *cc, 1261 struct dm_crypt_request *dmreq) 1262 { 1263 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + cc->iv_size; 1264 1265 return (__le64 *) ptr; 1266 } 1267 1268 static unsigned int *org_tag_of_dmreq(struct crypt_config *cc, 1269 struct dm_crypt_request *dmreq) 1270 { 1271 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + 1272 cc->iv_size + sizeof(uint64_t); 1273 1274 return (unsigned int *)ptr; 1275 } 1276 1277 static void *tag_from_dmreq(struct crypt_config *cc, 1278 struct dm_crypt_request *dmreq) 1279 { 1280 struct convert_context *ctx = dmreq->ctx; 1281 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 1282 1283 return &io->integrity_metadata[*org_tag_of_dmreq(cc, dmreq) * 1284 cc->on_disk_tag_size]; 1285 } 1286 1287 static void *iv_tag_from_dmreq(struct crypt_config *cc, 1288 struct dm_crypt_request *dmreq) 1289 { 1290 return tag_from_dmreq(cc, dmreq) + cc->integrity_tag_size; 1291 } 1292 1293 static int crypt_convert_block_aead(struct crypt_config *cc, 1294 struct convert_context *ctx, 1295 struct aead_request *req, 1296 unsigned int tag_offset) 1297 { 1298 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1299 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1300 struct dm_crypt_request *dmreq; 1301 u8 *iv, *org_iv, *tag_iv, *tag; 1302 __le64 *sector; 1303 int r = 0; 1304 1305 BUG_ON(cc->integrity_iv_size && cc->integrity_iv_size != cc->iv_size); 1306 1307 /* Reject unexpected unaligned bio. */ 1308 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1309 return -EIO; 1310 1311 dmreq = dmreq_of_req(cc, req); 1312 dmreq->iv_sector = ctx->cc_sector; 1313 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1314 dmreq->iv_sector >>= cc->sector_shift; 1315 dmreq->ctx = ctx; 1316 1317 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1318 1319 sector = org_sector_of_dmreq(cc, dmreq); 1320 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1321 1322 iv = iv_of_dmreq(cc, dmreq); 1323 org_iv = org_iv_of_dmreq(cc, dmreq); 1324 tag = tag_from_dmreq(cc, dmreq); 1325 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1326 1327 /* AEAD request: 1328 * |----- AAD -------|------ DATA -------|-- AUTH TAG --| 1329 * | (authenticated) | (auth+encryption) | | 1330 * | sector_LE | IV | sector in/out | tag in/out | 1331 */ 1332 sg_init_table(dmreq->sg_in, 4); 1333 sg_set_buf(&dmreq->sg_in[0], sector, sizeof(uint64_t)); 1334 sg_set_buf(&dmreq->sg_in[1], org_iv, cc->iv_size); 1335 sg_set_page(&dmreq->sg_in[2], bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1336 sg_set_buf(&dmreq->sg_in[3], tag, cc->integrity_tag_size); 1337 1338 sg_init_table(dmreq->sg_out, 4); 1339 sg_set_buf(&dmreq->sg_out[0], sector, sizeof(uint64_t)); 1340 sg_set_buf(&dmreq->sg_out[1], org_iv, cc->iv_size); 1341 sg_set_page(&dmreq->sg_out[2], bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1342 sg_set_buf(&dmreq->sg_out[3], tag, cc->integrity_tag_size); 1343 1344 if (cc->iv_gen_ops) { 1345 /* For READs use IV stored in integrity metadata */ 1346 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1347 memcpy(org_iv, tag_iv, cc->iv_size); 1348 } else { 1349 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1350 if (r < 0) 1351 return r; 1352 /* Store generated IV in integrity metadata */ 1353 if (cc->integrity_iv_size) 1354 memcpy(tag_iv, org_iv, cc->iv_size); 1355 } 1356 /* Working copy of IV, to be modified in crypto API */ 1357 memcpy(iv, org_iv, cc->iv_size); 1358 } 1359 1360 aead_request_set_ad(req, sizeof(uint64_t) + cc->iv_size); 1361 if (bio_data_dir(ctx->bio_in) == WRITE) { 1362 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out, 1363 cc->sector_size, iv); 1364 r = crypto_aead_encrypt(req); 1365 if (cc->integrity_tag_size + cc->integrity_iv_size != cc->on_disk_tag_size) 1366 memset(tag + cc->integrity_tag_size + cc->integrity_iv_size, 0, 1367 cc->on_disk_tag_size - (cc->integrity_tag_size + cc->integrity_iv_size)); 1368 } else { 1369 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out, 1370 cc->sector_size + cc->integrity_tag_size, iv); 1371 r = crypto_aead_decrypt(req); 1372 } 1373 1374 if (r == -EBADMSG) { 1375 sector_t s = le64_to_cpu(*sector); 1376 1377 ctx->aead_failed = true; 1378 if (ctx->aead_recheck) { 1379 DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu", 1380 ctx->bio_in->bi_bdev, s); 1381 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead", 1382 ctx->bio_in, s, 0); 1383 } 1384 } 1385 1386 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1387 r = cc->iv_gen_ops->post(cc, org_iv, dmreq); 1388 1389 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1390 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1391 1392 return r; 1393 } 1394 1395 static int crypt_convert_block_skcipher(struct crypt_config *cc, 1396 struct convert_context *ctx, 1397 struct skcipher_request *req, 1398 unsigned int tag_offset) 1399 { 1400 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1401 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1402 struct scatterlist *sg_in, *sg_out; 1403 struct dm_crypt_request *dmreq; 1404 u8 *iv, *org_iv, *tag_iv; 1405 __le64 *sector; 1406 int r = 0; 1407 1408 /* Reject unexpected unaligned bio. */ 1409 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1410 return -EIO; 1411 1412 dmreq = dmreq_of_req(cc, req); 1413 dmreq->iv_sector = ctx->cc_sector; 1414 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1415 dmreq->iv_sector >>= cc->sector_shift; 1416 dmreq->ctx = ctx; 1417 1418 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1419 1420 iv = iv_of_dmreq(cc, dmreq); 1421 org_iv = org_iv_of_dmreq(cc, dmreq); 1422 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1423 1424 sector = org_sector_of_dmreq(cc, dmreq); 1425 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1426 1427 /* For skcipher we use only the first sg item */ 1428 sg_in = &dmreq->sg_in[0]; 1429 sg_out = &dmreq->sg_out[0]; 1430 1431 sg_init_table(sg_in, 1); 1432 sg_set_page(sg_in, bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1433 1434 sg_init_table(sg_out, 1); 1435 sg_set_page(sg_out, bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1436 1437 if (cc->iv_gen_ops) { 1438 /* For READs use IV stored in integrity metadata */ 1439 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1440 memcpy(org_iv, tag_iv, cc->integrity_iv_size); 1441 } else { 1442 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1443 if (r < 0) 1444 return r; 1445 /* Data can be already preprocessed in generator */ 1446 if (test_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags)) 1447 sg_in = sg_out; 1448 /* Store generated IV in integrity metadata */ 1449 if (cc->integrity_iv_size) 1450 memcpy(tag_iv, org_iv, cc->integrity_iv_size); 1451 } 1452 /* Working copy of IV, to be modified in crypto API */ 1453 memcpy(iv, org_iv, cc->iv_size); 1454 } 1455 1456 skcipher_request_set_crypt(req, sg_in, sg_out, cc->sector_size, iv); 1457 1458 if (bio_data_dir(ctx->bio_in) == WRITE) 1459 r = crypto_skcipher_encrypt(req); 1460 else 1461 r = crypto_skcipher_decrypt(req); 1462 1463 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1464 r = cc->iv_gen_ops->post(cc, org_iv, dmreq); 1465 1466 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1467 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1468 1469 return r; 1470 } 1471 1472 static void kcryptd_async_done(void *async_req, int error); 1473 1474 static int crypt_alloc_req_skcipher(struct crypt_config *cc, 1475 struct convert_context *ctx) 1476 { 1477 unsigned int key_index = ctx->cc_sector & (cc->tfms_count - 1); 1478 1479 if (!ctx->r.req) { 1480 ctx->r.req = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1481 if (!ctx->r.req) 1482 return -ENOMEM; 1483 } 1484 1485 skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]); 1486 1487 /* 1488 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1489 * requests if driver request queue is full. 1490 */ 1491 skcipher_request_set_callback(ctx->r.req, 1492 CRYPTO_TFM_REQ_MAY_BACKLOG, 1493 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req)); 1494 1495 return 0; 1496 } 1497 1498 static int crypt_alloc_req_aead(struct crypt_config *cc, 1499 struct convert_context *ctx) 1500 { 1501 if (!ctx->r.req_aead) { 1502 ctx->r.req_aead = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1503 if (!ctx->r.req_aead) 1504 return -ENOMEM; 1505 } 1506 1507 aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]); 1508 1509 /* 1510 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1511 * requests if driver request queue is full. 1512 */ 1513 aead_request_set_callback(ctx->r.req_aead, 1514 CRYPTO_TFM_REQ_MAY_BACKLOG, 1515 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead)); 1516 1517 return 0; 1518 } 1519 1520 static int crypt_alloc_req(struct crypt_config *cc, 1521 struct convert_context *ctx) 1522 { 1523 if (crypt_integrity_aead(cc)) 1524 return crypt_alloc_req_aead(cc, ctx); 1525 else 1526 return crypt_alloc_req_skcipher(cc, ctx); 1527 } 1528 1529 static void crypt_free_req_skcipher(struct crypt_config *cc, 1530 struct skcipher_request *req, struct bio *base_bio) 1531 { 1532 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1533 1534 if ((struct skcipher_request *)(io + 1) != req) 1535 mempool_free(req, &cc->req_pool); 1536 } 1537 1538 static void crypt_free_req_aead(struct crypt_config *cc, 1539 struct aead_request *req, struct bio *base_bio) 1540 { 1541 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1542 1543 if ((struct aead_request *)(io + 1) != req) 1544 mempool_free(req, &cc->req_pool); 1545 } 1546 1547 static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio) 1548 { 1549 if (crypt_integrity_aead(cc)) 1550 crypt_free_req_aead(cc, req, base_bio); 1551 else 1552 crypt_free_req_skcipher(cc, req, base_bio); 1553 } 1554 1555 /* 1556 * Encrypt / decrypt data from one bio to another one (can be the same one) 1557 */ 1558 static blk_status_t crypt_convert(struct crypt_config *cc, 1559 struct convert_context *ctx, bool atomic, bool reset_pending) 1560 { 1561 unsigned int tag_offset = 0; 1562 unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT; 1563 int r; 1564 1565 /* 1566 * if reset_pending is set we are dealing with the bio for the first time, 1567 * else we're continuing to work on the previous bio, so don't mess with 1568 * the cc_pending counter 1569 */ 1570 if (reset_pending) 1571 atomic_set(&ctx->cc_pending, 1); 1572 1573 while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) { 1574 1575 r = crypt_alloc_req(cc, ctx); 1576 if (r) { 1577 complete(&ctx->restart); 1578 return BLK_STS_DEV_RESOURCE; 1579 } 1580 1581 atomic_inc(&ctx->cc_pending); 1582 1583 if (crypt_integrity_aead(cc)) 1584 r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, tag_offset); 1585 else 1586 r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, tag_offset); 1587 1588 switch (r) { 1589 /* 1590 * The request was queued by a crypto driver 1591 * but the driver request queue is full, let's wait. 1592 */ 1593 case -EBUSY: 1594 if (in_interrupt()) { 1595 if (try_wait_for_completion(&ctx->restart)) { 1596 /* 1597 * we don't have to block to wait for completion, 1598 * so proceed 1599 */ 1600 } else { 1601 /* 1602 * we can't wait for completion without blocking 1603 * exit and continue processing in a workqueue 1604 */ 1605 ctx->r.req = NULL; 1606 ctx->cc_sector += sector_step; 1607 tag_offset++; 1608 return BLK_STS_DEV_RESOURCE; 1609 } 1610 } else { 1611 wait_for_completion(&ctx->restart); 1612 } 1613 reinit_completion(&ctx->restart); 1614 fallthrough; 1615 /* 1616 * The request is queued and processed asynchronously, 1617 * completion function kcryptd_async_done() will be called. 1618 */ 1619 case -EINPROGRESS: 1620 ctx->r.req = NULL; 1621 ctx->cc_sector += sector_step; 1622 tag_offset++; 1623 continue; 1624 /* 1625 * The request was already processed (synchronously). 1626 */ 1627 case 0: 1628 atomic_dec(&ctx->cc_pending); 1629 ctx->cc_sector += sector_step; 1630 tag_offset++; 1631 if (!atomic) 1632 cond_resched(); 1633 continue; 1634 /* 1635 * There was a data integrity error. 1636 */ 1637 case -EBADMSG: 1638 atomic_dec(&ctx->cc_pending); 1639 return BLK_STS_PROTECTION; 1640 /* 1641 * There was an error while processing the request. 1642 */ 1643 default: 1644 atomic_dec(&ctx->cc_pending); 1645 return BLK_STS_IOERR; 1646 } 1647 } 1648 1649 return 0; 1650 } 1651 1652 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone); 1653 1654 /* 1655 * Generate a new unfragmented bio with the given size 1656 * This should never violate the device limitations (but only because 1657 * max_segment_size is being constrained to PAGE_SIZE). 1658 * 1659 * This function may be called concurrently. If we allocate from the mempool 1660 * concurrently, there is a possibility of deadlock. For example, if we have 1661 * mempool of 256 pages, two processes, each wanting 256, pages allocate from 1662 * the mempool concurrently, it may deadlock in a situation where both processes 1663 * have allocated 128 pages and the mempool is exhausted. 1664 * 1665 * In order to avoid this scenario we allocate the pages under a mutex. 1666 * 1667 * In order to not degrade performance with excessive locking, we try 1668 * non-blocking allocations without a mutex first but on failure we fallback 1669 * to blocking allocations with a mutex. 1670 * 1671 * In order to reduce allocation overhead, we try to allocate compound pages in 1672 * the first pass. If they are not available, we fall back to the mempool. 1673 */ 1674 static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned int size) 1675 { 1676 struct crypt_config *cc = io->cc; 1677 struct bio *clone; 1678 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; 1679 gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM; 1680 unsigned int remaining_size; 1681 unsigned int order = MAX_PAGE_ORDER; 1682 1683 retry: 1684 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1685 mutex_lock(&cc->bio_alloc_lock); 1686 1687 clone = bio_alloc_bioset(cc->dev->bdev, nr_iovecs, io->base_bio->bi_opf, 1688 GFP_NOIO, &cc->bs); 1689 clone->bi_private = io; 1690 clone->bi_end_io = crypt_endio; 1691 clone->bi_ioprio = io->base_bio->bi_ioprio; 1692 1693 remaining_size = size; 1694 1695 while (remaining_size) { 1696 struct page *pages; 1697 unsigned size_to_add; 1698 unsigned remaining_order = __fls((remaining_size + PAGE_SIZE - 1) >> PAGE_SHIFT); 1699 order = min(order, remaining_order); 1700 1701 while (order > 0) { 1702 if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) + 1703 (1 << order) > dm_crypt_pages_per_client)) 1704 goto decrease_order; 1705 pages = alloc_pages(gfp_mask 1706 | __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN | __GFP_COMP, 1707 order); 1708 if (likely(pages != NULL)) { 1709 percpu_counter_add(&cc->n_allocated_pages, 1 << order); 1710 goto have_pages; 1711 } 1712 decrease_order: 1713 order--; 1714 } 1715 1716 pages = mempool_alloc(&cc->page_pool, gfp_mask); 1717 if (!pages) { 1718 crypt_free_buffer_pages(cc, clone); 1719 bio_put(clone); 1720 gfp_mask |= __GFP_DIRECT_RECLAIM; 1721 order = 0; 1722 goto retry; 1723 } 1724 1725 have_pages: 1726 size_to_add = min((unsigned)PAGE_SIZE << order, remaining_size); 1727 __bio_add_page(clone, pages, size_to_add, 0); 1728 remaining_size -= size_to_add; 1729 } 1730 1731 /* Allocate space for integrity tags */ 1732 if (dm_crypt_integrity_io_alloc(io, clone)) { 1733 crypt_free_buffer_pages(cc, clone); 1734 bio_put(clone); 1735 clone = NULL; 1736 } 1737 1738 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1739 mutex_unlock(&cc->bio_alloc_lock); 1740 1741 return clone; 1742 } 1743 1744 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) 1745 { 1746 struct folio_iter fi; 1747 1748 if (clone->bi_vcnt > 0) { /* bio_for_each_folio_all crashes with an empty bio */ 1749 bio_for_each_folio_all(fi, clone) { 1750 if (folio_test_large(fi.folio)) { 1751 percpu_counter_sub(&cc->n_allocated_pages, 1752 1 << folio_order(fi.folio)); 1753 folio_put(fi.folio); 1754 } else { 1755 mempool_free(&fi.folio->page, &cc->page_pool); 1756 } 1757 } 1758 } 1759 } 1760 1761 static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc, 1762 struct bio *bio, sector_t sector) 1763 { 1764 io->cc = cc; 1765 io->base_bio = bio; 1766 io->sector = sector; 1767 io->error = 0; 1768 io->ctx.aead_recheck = false; 1769 io->ctx.aead_failed = false; 1770 io->ctx.r.req = NULL; 1771 io->integrity_metadata = NULL; 1772 io->integrity_metadata_from_pool = false; 1773 atomic_set(&io->io_pending, 0); 1774 } 1775 1776 static void crypt_inc_pending(struct dm_crypt_io *io) 1777 { 1778 atomic_inc(&io->io_pending); 1779 } 1780 1781 static void kcryptd_queue_read(struct dm_crypt_io *io); 1782 1783 /* 1784 * One of the bios was finished. Check for completion of 1785 * the whole request and correctly clean up the buffer. 1786 */ 1787 static void crypt_dec_pending(struct dm_crypt_io *io) 1788 { 1789 struct crypt_config *cc = io->cc; 1790 struct bio *base_bio = io->base_bio; 1791 blk_status_t error = io->error; 1792 1793 if (!atomic_dec_and_test(&io->io_pending)) 1794 return; 1795 1796 if (likely(!io->ctx.aead_recheck) && unlikely(io->ctx.aead_failed) && 1797 cc->on_disk_tag_size && bio_data_dir(base_bio) == READ) { 1798 io->ctx.aead_recheck = true; 1799 io->ctx.aead_failed = false; 1800 io->error = 0; 1801 kcryptd_queue_read(io); 1802 return; 1803 } 1804 1805 if (io->ctx.r.req) 1806 crypt_free_req(cc, io->ctx.r.req, base_bio); 1807 1808 if (unlikely(io->integrity_metadata_from_pool)) 1809 mempool_free(io->integrity_metadata, &io->cc->tag_pool); 1810 else 1811 kfree(io->integrity_metadata); 1812 1813 base_bio->bi_status = error; 1814 1815 bio_endio(base_bio); 1816 } 1817 1818 /* 1819 * kcryptd/kcryptd_io: 1820 * 1821 * Needed because it would be very unwise to do decryption in an 1822 * interrupt context. 1823 * 1824 * kcryptd performs the actual encryption or decryption. 1825 * 1826 * kcryptd_io performs the IO submission. 1827 * 1828 * They must be separated as otherwise the final stages could be 1829 * starved by new requests which can block in the first stages due 1830 * to memory allocation. 1831 * 1832 * The work is done per CPU global for all dm-crypt instances. 1833 * They should not depend on each other and do not block. 1834 */ 1835 static void crypt_endio(struct bio *clone) 1836 { 1837 struct dm_crypt_io *io = clone->bi_private; 1838 struct crypt_config *cc = io->cc; 1839 unsigned int rw = bio_data_dir(clone); 1840 blk_status_t error = clone->bi_status; 1841 1842 if (io->ctx.aead_recheck && !error) { 1843 kcryptd_queue_crypt(io); 1844 return; 1845 } 1846 1847 /* 1848 * free the processed pages 1849 */ 1850 if (rw == WRITE || io->ctx.aead_recheck) 1851 crypt_free_buffer_pages(cc, clone); 1852 1853 bio_put(clone); 1854 1855 if (rw == READ && !error) { 1856 kcryptd_queue_crypt(io); 1857 return; 1858 } 1859 1860 if (unlikely(error)) 1861 io->error = error; 1862 1863 crypt_dec_pending(io); 1864 } 1865 1866 #define CRYPT_MAP_READ_GFP GFP_NOWAIT 1867 1868 static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp) 1869 { 1870 struct crypt_config *cc = io->cc; 1871 struct bio *clone; 1872 1873 if (io->ctx.aead_recheck) { 1874 if (!(gfp & __GFP_DIRECT_RECLAIM)) 1875 return 1; 1876 crypt_inc_pending(io); 1877 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size); 1878 if (unlikely(!clone)) { 1879 crypt_dec_pending(io); 1880 return 1; 1881 } 1882 clone->bi_iter.bi_sector = cc->start + io->sector; 1883 crypt_convert_init(cc, &io->ctx, clone, clone, io->sector); 1884 io->saved_bi_iter = clone->bi_iter; 1885 dm_submit_bio_remap(io->base_bio, clone); 1886 return 0; 1887 } 1888 1889 /* 1890 * We need the original biovec array in order to decrypt the whole bio 1891 * data *afterwards* -- thanks to immutable biovecs we don't need to 1892 * worry about the block layer modifying the biovec array; so leverage 1893 * bio_alloc_clone(). 1894 */ 1895 clone = bio_alloc_clone(cc->dev->bdev, io->base_bio, gfp, &cc->bs); 1896 if (!clone) 1897 return 1; 1898 clone->bi_private = io; 1899 clone->bi_end_io = crypt_endio; 1900 1901 crypt_inc_pending(io); 1902 1903 clone->bi_iter.bi_sector = cc->start + io->sector; 1904 1905 if (dm_crypt_integrity_io_alloc(io, clone)) { 1906 crypt_dec_pending(io); 1907 bio_put(clone); 1908 return 1; 1909 } 1910 1911 dm_submit_bio_remap(io->base_bio, clone); 1912 return 0; 1913 } 1914 1915 static void kcryptd_io_read_work(struct work_struct *work) 1916 { 1917 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 1918 1919 crypt_inc_pending(io); 1920 if (kcryptd_io_read(io, GFP_NOIO)) 1921 io->error = BLK_STS_RESOURCE; 1922 crypt_dec_pending(io); 1923 } 1924 1925 static void kcryptd_queue_read(struct dm_crypt_io *io) 1926 { 1927 struct crypt_config *cc = io->cc; 1928 1929 INIT_WORK(&io->work, kcryptd_io_read_work); 1930 queue_work(cc->io_queue, &io->work); 1931 } 1932 1933 static void kcryptd_io_write(struct dm_crypt_io *io) 1934 { 1935 struct bio *clone = io->ctx.bio_out; 1936 1937 dm_submit_bio_remap(io->base_bio, clone); 1938 } 1939 1940 #define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node) 1941 1942 static int dmcrypt_write(void *data) 1943 { 1944 struct crypt_config *cc = data; 1945 struct dm_crypt_io *io; 1946 1947 while (1) { 1948 struct rb_root write_tree; 1949 struct blk_plug plug; 1950 1951 spin_lock_irq(&cc->write_thread_lock); 1952 continue_locked: 1953 1954 if (!RB_EMPTY_ROOT(&cc->write_tree)) 1955 goto pop_from_list; 1956 1957 set_current_state(TASK_INTERRUPTIBLE); 1958 1959 spin_unlock_irq(&cc->write_thread_lock); 1960 1961 if (unlikely(kthread_should_stop())) { 1962 set_current_state(TASK_RUNNING); 1963 break; 1964 } 1965 1966 schedule(); 1967 1968 spin_lock_irq(&cc->write_thread_lock); 1969 goto continue_locked; 1970 1971 pop_from_list: 1972 write_tree = cc->write_tree; 1973 cc->write_tree = RB_ROOT; 1974 spin_unlock_irq(&cc->write_thread_lock); 1975 1976 BUG_ON(rb_parent(write_tree.rb_node)); 1977 1978 /* 1979 * Note: we cannot walk the tree here with rb_next because 1980 * the structures may be freed when kcryptd_io_write is called. 1981 */ 1982 blk_start_plug(&plug); 1983 do { 1984 io = crypt_io_from_node(rb_first(&write_tree)); 1985 rb_erase(&io->rb_node, &write_tree); 1986 kcryptd_io_write(io); 1987 cond_resched(); 1988 } while (!RB_EMPTY_ROOT(&write_tree)); 1989 blk_finish_plug(&plug); 1990 } 1991 return 0; 1992 } 1993 1994 static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async) 1995 { 1996 struct bio *clone = io->ctx.bio_out; 1997 struct crypt_config *cc = io->cc; 1998 unsigned long flags; 1999 sector_t sector; 2000 struct rb_node **rbp, *parent; 2001 2002 if (unlikely(io->error)) { 2003 crypt_free_buffer_pages(cc, clone); 2004 bio_put(clone); 2005 crypt_dec_pending(io); 2006 return; 2007 } 2008 2009 /* crypt_convert should have filled the clone bio */ 2010 BUG_ON(io->ctx.iter_out.bi_size); 2011 2012 clone->bi_iter.bi_sector = cc->start + io->sector; 2013 2014 if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) || 2015 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) { 2016 dm_submit_bio_remap(io->base_bio, clone); 2017 return; 2018 } 2019 2020 spin_lock_irqsave(&cc->write_thread_lock, flags); 2021 if (RB_EMPTY_ROOT(&cc->write_tree)) 2022 wake_up_process(cc->write_thread); 2023 rbp = &cc->write_tree.rb_node; 2024 parent = NULL; 2025 sector = io->sector; 2026 while (*rbp) { 2027 parent = *rbp; 2028 if (sector < crypt_io_from_node(parent)->sector) 2029 rbp = &(*rbp)->rb_left; 2030 else 2031 rbp = &(*rbp)->rb_right; 2032 } 2033 rb_link_node(&io->rb_node, parent, rbp); 2034 rb_insert_color(&io->rb_node, &cc->write_tree); 2035 spin_unlock_irqrestore(&cc->write_thread_lock, flags); 2036 } 2037 2038 static bool kcryptd_crypt_write_inline(struct crypt_config *cc, 2039 struct convert_context *ctx) 2040 2041 { 2042 if (!test_bit(DM_CRYPT_WRITE_INLINE, &cc->flags)) 2043 return false; 2044 2045 /* 2046 * Note: zone append writes (REQ_OP_ZONE_APPEND) do not have ordering 2047 * constraints so they do not need to be issued inline by 2048 * kcryptd_crypt_write_convert(). 2049 */ 2050 switch (bio_op(ctx->bio_in)) { 2051 case REQ_OP_WRITE: 2052 case REQ_OP_WRITE_ZEROES: 2053 return true; 2054 default: 2055 return false; 2056 } 2057 } 2058 2059 static void kcryptd_crypt_write_continue(struct work_struct *work) 2060 { 2061 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2062 struct crypt_config *cc = io->cc; 2063 struct convert_context *ctx = &io->ctx; 2064 int crypt_finished; 2065 sector_t sector = io->sector; 2066 blk_status_t r; 2067 2068 wait_for_completion(&ctx->restart); 2069 reinit_completion(&ctx->restart); 2070 2071 r = crypt_convert(cc, &io->ctx, true, false); 2072 if (r) 2073 io->error = r; 2074 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2075 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2076 /* Wait for completion signaled by kcryptd_async_done() */ 2077 wait_for_completion(&ctx->restart); 2078 crypt_finished = 1; 2079 } 2080 2081 /* Encryption was already finished, submit io now */ 2082 if (crypt_finished) { 2083 kcryptd_crypt_write_io_submit(io, 0); 2084 io->sector = sector; 2085 } 2086 2087 crypt_dec_pending(io); 2088 } 2089 2090 static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) 2091 { 2092 struct crypt_config *cc = io->cc; 2093 struct convert_context *ctx = &io->ctx; 2094 struct bio *clone; 2095 int crypt_finished; 2096 sector_t sector = io->sector; 2097 blk_status_t r; 2098 2099 /* 2100 * Prevent io from disappearing until this function completes. 2101 */ 2102 crypt_inc_pending(io); 2103 crypt_convert_init(cc, ctx, NULL, io->base_bio, sector); 2104 2105 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size); 2106 if (unlikely(!clone)) { 2107 io->error = BLK_STS_IOERR; 2108 goto dec; 2109 } 2110 2111 io->ctx.bio_out = clone; 2112 io->ctx.iter_out = clone->bi_iter; 2113 2114 if (crypt_integrity_aead(cc)) { 2115 bio_copy_data(clone, io->base_bio); 2116 io->ctx.bio_in = clone; 2117 io->ctx.iter_in = clone->bi_iter; 2118 } 2119 2120 sector += bio_sectors(clone); 2121 2122 crypt_inc_pending(io); 2123 r = crypt_convert(cc, ctx, 2124 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags), true); 2125 /* 2126 * Crypto API backlogged the request, because its queue was full 2127 * and we're in softirq context, so continue from a workqueue 2128 * (TODO: is it actually possible to be in softirq in the write path?) 2129 */ 2130 if (r == BLK_STS_DEV_RESOURCE) { 2131 INIT_WORK(&io->work, kcryptd_crypt_write_continue); 2132 queue_work(cc->crypt_queue, &io->work); 2133 return; 2134 } 2135 if (r) 2136 io->error = r; 2137 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2138 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2139 /* Wait for completion signaled by kcryptd_async_done() */ 2140 wait_for_completion(&ctx->restart); 2141 crypt_finished = 1; 2142 } 2143 2144 /* Encryption was already finished, submit io now */ 2145 if (crypt_finished) { 2146 kcryptd_crypt_write_io_submit(io, 0); 2147 io->sector = sector; 2148 } 2149 2150 dec: 2151 crypt_dec_pending(io); 2152 } 2153 2154 static void kcryptd_crypt_read_done(struct dm_crypt_io *io) 2155 { 2156 if (io->ctx.aead_recheck) { 2157 if (!io->error) { 2158 io->ctx.bio_in->bi_iter = io->saved_bi_iter; 2159 bio_copy_data(io->base_bio, io->ctx.bio_in); 2160 } 2161 crypt_free_buffer_pages(io->cc, io->ctx.bio_in); 2162 bio_put(io->ctx.bio_in); 2163 } 2164 crypt_dec_pending(io); 2165 } 2166 2167 static void kcryptd_crypt_read_continue(struct work_struct *work) 2168 { 2169 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2170 struct crypt_config *cc = io->cc; 2171 blk_status_t r; 2172 2173 wait_for_completion(&io->ctx.restart); 2174 reinit_completion(&io->ctx.restart); 2175 2176 r = crypt_convert(cc, &io->ctx, true, false); 2177 if (r) 2178 io->error = r; 2179 2180 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2181 kcryptd_crypt_read_done(io); 2182 2183 crypt_dec_pending(io); 2184 } 2185 2186 static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) 2187 { 2188 struct crypt_config *cc = io->cc; 2189 blk_status_t r; 2190 2191 crypt_inc_pending(io); 2192 2193 if (io->ctx.aead_recheck) { 2194 io->ctx.cc_sector = io->sector + cc->iv_offset; 2195 r = crypt_convert(cc, &io->ctx, 2196 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true); 2197 } else { 2198 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, 2199 io->sector); 2200 2201 r = crypt_convert(cc, &io->ctx, 2202 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true); 2203 } 2204 /* 2205 * Crypto API backlogged the request, because its queue was full 2206 * and we're in softirq context, so continue from a workqueue 2207 */ 2208 if (r == BLK_STS_DEV_RESOURCE) { 2209 INIT_WORK(&io->work, kcryptd_crypt_read_continue); 2210 queue_work(cc->crypt_queue, &io->work); 2211 return; 2212 } 2213 if (r) 2214 io->error = r; 2215 2216 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2217 kcryptd_crypt_read_done(io); 2218 2219 crypt_dec_pending(io); 2220 } 2221 2222 static void kcryptd_async_done(void *data, int error) 2223 { 2224 struct dm_crypt_request *dmreq = data; 2225 struct convert_context *ctx = dmreq->ctx; 2226 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 2227 struct crypt_config *cc = io->cc; 2228 2229 /* 2230 * A request from crypto driver backlog is going to be processed now, 2231 * finish the completion and continue in crypt_convert(). 2232 * (Callback will be called for the second time for this request.) 2233 */ 2234 if (error == -EINPROGRESS) { 2235 complete(&ctx->restart); 2236 return; 2237 } 2238 2239 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post) 2240 error = cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq); 2241 2242 if (error == -EBADMSG) { 2243 sector_t s = le64_to_cpu(*org_sector_of_dmreq(cc, dmreq)); 2244 2245 ctx->aead_failed = true; 2246 if (ctx->aead_recheck) { 2247 DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu", 2248 ctx->bio_in->bi_bdev, s); 2249 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead", 2250 ctx->bio_in, s, 0); 2251 } 2252 io->error = BLK_STS_PROTECTION; 2253 } else if (error < 0) 2254 io->error = BLK_STS_IOERR; 2255 2256 crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio); 2257 2258 if (!atomic_dec_and_test(&ctx->cc_pending)) 2259 return; 2260 2261 /* 2262 * The request is fully completed: for inline writes, let 2263 * kcryptd_crypt_write_convert() do the IO submission. 2264 */ 2265 if (bio_data_dir(io->base_bio) == READ) { 2266 kcryptd_crypt_read_done(io); 2267 return; 2268 } 2269 2270 if (kcryptd_crypt_write_inline(cc, ctx)) { 2271 complete(&ctx->restart); 2272 return; 2273 } 2274 2275 kcryptd_crypt_write_io_submit(io, 1); 2276 } 2277 2278 static void kcryptd_crypt(struct work_struct *work) 2279 { 2280 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2281 2282 if (bio_data_dir(io->base_bio) == READ) 2283 kcryptd_crypt_read_convert(io); 2284 else 2285 kcryptd_crypt_write_convert(io); 2286 } 2287 2288 static void kcryptd_queue_crypt(struct dm_crypt_io *io) 2289 { 2290 struct crypt_config *cc = io->cc; 2291 2292 if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) || 2293 (bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) { 2294 /* 2295 * in_hardirq(): Crypto API's skcipher_walk_first() refuses to work in hard IRQ context. 2296 * irqs_disabled(): the kernel may run some IO completion from the idle thread, but 2297 * it is being executed with irqs disabled. 2298 */ 2299 if (in_hardirq() || irqs_disabled()) { 2300 INIT_WORK(&io->work, kcryptd_crypt); 2301 queue_work(system_bh_wq, &io->work); 2302 return; 2303 } else { 2304 kcryptd_crypt(&io->work); 2305 return; 2306 } 2307 } 2308 2309 INIT_WORK(&io->work, kcryptd_crypt); 2310 queue_work(cc->crypt_queue, &io->work); 2311 } 2312 2313 static void crypt_free_tfms_aead(struct crypt_config *cc) 2314 { 2315 if (!cc->cipher_tfm.tfms_aead) 2316 return; 2317 2318 if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2319 crypto_free_aead(cc->cipher_tfm.tfms_aead[0]); 2320 cc->cipher_tfm.tfms_aead[0] = NULL; 2321 } 2322 2323 kfree(cc->cipher_tfm.tfms_aead); 2324 cc->cipher_tfm.tfms_aead = NULL; 2325 } 2326 2327 static void crypt_free_tfms_skcipher(struct crypt_config *cc) 2328 { 2329 unsigned int i; 2330 2331 if (!cc->cipher_tfm.tfms) 2332 return; 2333 2334 for (i = 0; i < cc->tfms_count; i++) 2335 if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) { 2336 crypto_free_skcipher(cc->cipher_tfm.tfms[i]); 2337 cc->cipher_tfm.tfms[i] = NULL; 2338 } 2339 2340 kfree(cc->cipher_tfm.tfms); 2341 cc->cipher_tfm.tfms = NULL; 2342 } 2343 2344 static void crypt_free_tfms(struct crypt_config *cc) 2345 { 2346 if (crypt_integrity_aead(cc)) 2347 crypt_free_tfms_aead(cc); 2348 else 2349 crypt_free_tfms_skcipher(cc); 2350 } 2351 2352 static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode) 2353 { 2354 unsigned int i; 2355 int err; 2356 2357 cc->cipher_tfm.tfms = kcalloc(cc->tfms_count, 2358 sizeof(struct crypto_skcipher *), 2359 GFP_KERNEL); 2360 if (!cc->cipher_tfm.tfms) 2361 return -ENOMEM; 2362 2363 for (i = 0; i < cc->tfms_count; i++) { 2364 cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0, 2365 CRYPTO_ALG_ALLOCATES_MEMORY); 2366 if (IS_ERR(cc->cipher_tfm.tfms[i])) { 2367 err = PTR_ERR(cc->cipher_tfm.tfms[i]); 2368 crypt_free_tfms(cc); 2369 return err; 2370 } 2371 } 2372 2373 /* 2374 * dm-crypt performance can vary greatly depending on which crypto 2375 * algorithm implementation is used. Help people debug performance 2376 * problems by logging the ->cra_driver_name. 2377 */ 2378 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2379 crypto_skcipher_alg(any_tfm(cc))->base.cra_driver_name); 2380 return 0; 2381 } 2382 2383 static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode) 2384 { 2385 int err; 2386 2387 cc->cipher_tfm.tfms = kmalloc(sizeof(struct crypto_aead *), GFP_KERNEL); 2388 if (!cc->cipher_tfm.tfms) 2389 return -ENOMEM; 2390 2391 cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0, 2392 CRYPTO_ALG_ALLOCATES_MEMORY); 2393 if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2394 err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]); 2395 crypt_free_tfms(cc); 2396 return err; 2397 } 2398 2399 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2400 crypto_aead_alg(any_tfm_aead(cc))->base.cra_driver_name); 2401 return 0; 2402 } 2403 2404 static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode) 2405 { 2406 if (crypt_integrity_aead(cc)) 2407 return crypt_alloc_tfms_aead(cc, ciphermode); 2408 else 2409 return crypt_alloc_tfms_skcipher(cc, ciphermode); 2410 } 2411 2412 static unsigned int crypt_subkey_size(struct crypt_config *cc) 2413 { 2414 return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count); 2415 } 2416 2417 static unsigned int crypt_authenckey_size(struct crypt_config *cc) 2418 { 2419 return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param)); 2420 } 2421 2422 /* 2423 * If AEAD is composed like authenc(hmac(sha256),xts(aes)), 2424 * the key must be for some reason in special format. 2425 * This funcion converts cc->key to this special format. 2426 */ 2427 static void crypt_copy_authenckey(char *p, const void *key, 2428 unsigned int enckeylen, unsigned int authkeylen) 2429 { 2430 struct crypto_authenc_key_param *param; 2431 struct rtattr *rta; 2432 2433 rta = (struct rtattr *)p; 2434 param = RTA_DATA(rta); 2435 param->enckeylen = cpu_to_be32(enckeylen); 2436 rta->rta_len = RTA_LENGTH(sizeof(*param)); 2437 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; 2438 p += RTA_SPACE(sizeof(*param)); 2439 memcpy(p, key + enckeylen, authkeylen); 2440 p += authkeylen; 2441 memcpy(p, key, enckeylen); 2442 } 2443 2444 static int crypt_setkey(struct crypt_config *cc) 2445 { 2446 unsigned int subkey_size; 2447 int err = 0, i, r; 2448 2449 /* Ignore extra keys (which are used for IV etc) */ 2450 subkey_size = crypt_subkey_size(cc); 2451 2452 if (crypt_integrity_hmac(cc)) { 2453 if (subkey_size < cc->key_mac_size) 2454 return -EINVAL; 2455 2456 crypt_copy_authenckey(cc->authenc_key, cc->key, 2457 subkey_size - cc->key_mac_size, 2458 cc->key_mac_size); 2459 } 2460 2461 for (i = 0; i < cc->tfms_count; i++) { 2462 if (crypt_integrity_hmac(cc)) 2463 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2464 cc->authenc_key, crypt_authenckey_size(cc)); 2465 else if (crypt_integrity_aead(cc)) 2466 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2467 cc->key + (i * subkey_size), 2468 subkey_size); 2469 else 2470 r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i], 2471 cc->key + (i * subkey_size), 2472 subkey_size); 2473 if (r) 2474 err = r; 2475 } 2476 2477 if (crypt_integrity_hmac(cc)) 2478 memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc)); 2479 2480 return err; 2481 } 2482 2483 #ifdef CONFIG_KEYS 2484 2485 static bool contains_whitespace(const char *str) 2486 { 2487 while (*str) 2488 if (isspace(*str++)) 2489 return true; 2490 return false; 2491 } 2492 2493 static int set_key_user(struct crypt_config *cc, struct key *key) 2494 { 2495 const struct user_key_payload *ukp; 2496 2497 ukp = user_key_payload_locked(key); 2498 if (!ukp) 2499 return -EKEYREVOKED; 2500 2501 if (cc->key_size != ukp->datalen) 2502 return -EINVAL; 2503 2504 memcpy(cc->key, ukp->data, cc->key_size); 2505 2506 return 0; 2507 } 2508 2509 static int set_key_encrypted(struct crypt_config *cc, struct key *key) 2510 { 2511 const struct encrypted_key_payload *ekp; 2512 2513 ekp = key->payload.data[0]; 2514 if (!ekp) 2515 return -EKEYREVOKED; 2516 2517 if (cc->key_size != ekp->decrypted_datalen) 2518 return -EINVAL; 2519 2520 memcpy(cc->key, ekp->decrypted_data, cc->key_size); 2521 2522 return 0; 2523 } 2524 2525 static int set_key_trusted(struct crypt_config *cc, struct key *key) 2526 { 2527 const struct trusted_key_payload *tkp; 2528 2529 tkp = key->payload.data[0]; 2530 if (!tkp) 2531 return -EKEYREVOKED; 2532 2533 if (cc->key_size != tkp->key_len) 2534 return -EINVAL; 2535 2536 memcpy(cc->key, tkp->key, cc->key_size); 2537 2538 return 0; 2539 } 2540 2541 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2542 { 2543 char *new_key_string, *key_desc; 2544 int ret; 2545 struct key_type *type; 2546 struct key *key; 2547 int (*set_key)(struct crypt_config *cc, struct key *key); 2548 2549 /* 2550 * Reject key_string with whitespace. dm core currently lacks code for 2551 * proper whitespace escaping in arguments on DM_TABLE_STATUS path. 2552 */ 2553 if (contains_whitespace(key_string)) { 2554 DMERR("whitespace chars not allowed in key string"); 2555 return -EINVAL; 2556 } 2557 2558 /* look for next ':' separating key_type from key_description */ 2559 key_desc = strchr(key_string, ':'); 2560 if (!key_desc || key_desc == key_string || !strlen(key_desc + 1)) 2561 return -EINVAL; 2562 2563 if (!strncmp(key_string, "logon:", key_desc - key_string + 1)) { 2564 type = &key_type_logon; 2565 set_key = set_key_user; 2566 } else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) { 2567 type = &key_type_user; 2568 set_key = set_key_user; 2569 } else if (IS_ENABLED(CONFIG_ENCRYPTED_KEYS) && 2570 !strncmp(key_string, "encrypted:", key_desc - key_string + 1)) { 2571 type = &key_type_encrypted; 2572 set_key = set_key_encrypted; 2573 } else if (IS_ENABLED(CONFIG_TRUSTED_KEYS) && 2574 !strncmp(key_string, "trusted:", key_desc - key_string + 1)) { 2575 type = &key_type_trusted; 2576 set_key = set_key_trusted; 2577 } else { 2578 return -EINVAL; 2579 } 2580 2581 new_key_string = kstrdup(key_string, GFP_KERNEL); 2582 if (!new_key_string) 2583 return -ENOMEM; 2584 2585 key = request_key(type, key_desc + 1, NULL); 2586 if (IS_ERR(key)) { 2587 kfree_sensitive(new_key_string); 2588 return PTR_ERR(key); 2589 } 2590 2591 down_read(&key->sem); 2592 2593 ret = set_key(cc, key); 2594 if (ret < 0) { 2595 up_read(&key->sem); 2596 key_put(key); 2597 kfree_sensitive(new_key_string); 2598 return ret; 2599 } 2600 2601 up_read(&key->sem); 2602 key_put(key); 2603 2604 /* clear the flag since following operations may invalidate previously valid key */ 2605 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2606 2607 ret = crypt_setkey(cc); 2608 2609 if (!ret) { 2610 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2611 kfree_sensitive(cc->key_string); 2612 cc->key_string = new_key_string; 2613 } else 2614 kfree_sensitive(new_key_string); 2615 2616 return ret; 2617 } 2618 2619 static int get_key_size(char **key_string) 2620 { 2621 char *colon, dummy; 2622 int ret; 2623 2624 if (*key_string[0] != ':') 2625 return strlen(*key_string) >> 1; 2626 2627 /* look for next ':' in key string */ 2628 colon = strpbrk(*key_string + 1, ":"); 2629 if (!colon) 2630 return -EINVAL; 2631 2632 if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':') 2633 return -EINVAL; 2634 2635 *key_string = colon; 2636 2637 /* remaining key string should be :<logon|user>:<key_desc> */ 2638 2639 return ret; 2640 } 2641 2642 #else 2643 2644 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2645 { 2646 return -EINVAL; 2647 } 2648 2649 static int get_key_size(char **key_string) 2650 { 2651 return (*key_string[0] == ':') ? -EINVAL : (int)(strlen(*key_string) >> 1); 2652 } 2653 2654 #endif /* CONFIG_KEYS */ 2655 2656 static int crypt_set_key(struct crypt_config *cc, char *key) 2657 { 2658 int r = -EINVAL; 2659 int key_string_len = strlen(key); 2660 2661 /* Hyphen (which gives a key_size of zero) means there is no key. */ 2662 if (!cc->key_size && strcmp(key, "-")) 2663 goto out; 2664 2665 /* ':' means the key is in kernel keyring, short-circuit normal key processing */ 2666 if (key[0] == ':') { 2667 r = crypt_set_keyring_key(cc, key + 1); 2668 goto out; 2669 } 2670 2671 /* clear the flag since following operations may invalidate previously valid key */ 2672 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2673 2674 /* wipe references to any kernel keyring key */ 2675 kfree_sensitive(cc->key_string); 2676 cc->key_string = NULL; 2677 2678 /* Decode key from its hex representation. */ 2679 if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0) 2680 goto out; 2681 2682 r = crypt_setkey(cc); 2683 if (!r) 2684 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2685 2686 out: 2687 /* Hex key string not needed after here, so wipe it. */ 2688 memset(key, '0', key_string_len); 2689 2690 return r; 2691 } 2692 2693 static int crypt_wipe_key(struct crypt_config *cc) 2694 { 2695 int r; 2696 2697 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2698 get_random_bytes(&cc->key, cc->key_size); 2699 2700 /* Wipe IV private keys */ 2701 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) { 2702 r = cc->iv_gen_ops->wipe(cc); 2703 if (r) 2704 return r; 2705 } 2706 2707 kfree_sensitive(cc->key_string); 2708 cc->key_string = NULL; 2709 r = crypt_setkey(cc); 2710 memset(&cc->key, 0, cc->key_size * sizeof(u8)); 2711 2712 return r; 2713 } 2714 2715 static void crypt_calculate_pages_per_client(void) 2716 { 2717 unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100; 2718 2719 if (!dm_crypt_clients_n) 2720 return; 2721 2722 pages /= dm_crypt_clients_n; 2723 if (pages < DM_CRYPT_MIN_PAGES_PER_CLIENT) 2724 pages = DM_CRYPT_MIN_PAGES_PER_CLIENT; 2725 dm_crypt_pages_per_client = pages; 2726 } 2727 2728 static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data) 2729 { 2730 struct crypt_config *cc = pool_data; 2731 struct page *page; 2732 2733 /* 2734 * Note, percpu_counter_read_positive() may over (and under) estimate 2735 * the current usage by at most (batch - 1) * num_online_cpus() pages, 2736 * but avoids potential spinlock contention of an exact result. 2737 */ 2738 if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) >= dm_crypt_pages_per_client) && 2739 likely(gfp_mask & __GFP_NORETRY)) 2740 return NULL; 2741 2742 page = alloc_page(gfp_mask); 2743 if (likely(page != NULL)) 2744 percpu_counter_add(&cc->n_allocated_pages, 1); 2745 2746 return page; 2747 } 2748 2749 static void crypt_page_free(void *page, void *pool_data) 2750 { 2751 struct crypt_config *cc = pool_data; 2752 2753 __free_page(page); 2754 percpu_counter_sub(&cc->n_allocated_pages, 1); 2755 } 2756 2757 static void crypt_dtr(struct dm_target *ti) 2758 { 2759 struct crypt_config *cc = ti->private; 2760 2761 ti->private = NULL; 2762 2763 if (!cc) 2764 return; 2765 2766 if (cc->write_thread) 2767 kthread_stop(cc->write_thread); 2768 2769 if (cc->io_queue) 2770 destroy_workqueue(cc->io_queue); 2771 if (cc->crypt_queue) 2772 destroy_workqueue(cc->crypt_queue); 2773 2774 crypt_free_tfms(cc); 2775 2776 bioset_exit(&cc->bs); 2777 2778 mempool_exit(&cc->page_pool); 2779 mempool_exit(&cc->req_pool); 2780 mempool_exit(&cc->tag_pool); 2781 2782 WARN_ON(percpu_counter_sum(&cc->n_allocated_pages) != 0); 2783 percpu_counter_destroy(&cc->n_allocated_pages); 2784 2785 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) 2786 cc->iv_gen_ops->dtr(cc); 2787 2788 if (cc->dev) 2789 dm_put_device(ti, cc->dev); 2790 2791 kfree_sensitive(cc->cipher_string); 2792 kfree_sensitive(cc->key_string); 2793 kfree_sensitive(cc->cipher_auth); 2794 kfree_sensitive(cc->authenc_key); 2795 2796 mutex_destroy(&cc->bio_alloc_lock); 2797 2798 /* Must zero key material before freeing */ 2799 kfree_sensitive(cc); 2800 2801 spin_lock(&dm_crypt_clients_lock); 2802 WARN_ON(!dm_crypt_clients_n); 2803 dm_crypt_clients_n--; 2804 crypt_calculate_pages_per_client(); 2805 spin_unlock(&dm_crypt_clients_lock); 2806 2807 dm_audit_log_dtr(DM_MSG_PREFIX, ti, 1); 2808 } 2809 2810 static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode) 2811 { 2812 struct crypt_config *cc = ti->private; 2813 2814 if (crypt_integrity_aead(cc)) 2815 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2816 else 2817 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2818 2819 if (cc->iv_size) 2820 /* at least a 64 bit sector number should fit in our buffer */ 2821 cc->iv_size = max(cc->iv_size, 2822 (unsigned int)(sizeof(u64) / sizeof(u8))); 2823 else if (ivmode) { 2824 DMWARN("Selected cipher does not support IVs"); 2825 ivmode = NULL; 2826 } 2827 2828 /* Choose ivmode, see comments at iv code. */ 2829 if (ivmode == NULL) 2830 cc->iv_gen_ops = NULL; 2831 else if (strcmp(ivmode, "plain") == 0) 2832 cc->iv_gen_ops = &crypt_iv_plain_ops; 2833 else if (strcmp(ivmode, "plain64") == 0) 2834 cc->iv_gen_ops = &crypt_iv_plain64_ops; 2835 else if (strcmp(ivmode, "plain64be") == 0) 2836 cc->iv_gen_ops = &crypt_iv_plain64be_ops; 2837 else if (strcmp(ivmode, "essiv") == 0) 2838 cc->iv_gen_ops = &crypt_iv_essiv_ops; 2839 else if (strcmp(ivmode, "benbi") == 0) 2840 cc->iv_gen_ops = &crypt_iv_benbi_ops; 2841 else if (strcmp(ivmode, "null") == 0) 2842 cc->iv_gen_ops = &crypt_iv_null_ops; 2843 else if (strcmp(ivmode, "eboiv") == 0) 2844 cc->iv_gen_ops = &crypt_iv_eboiv_ops; 2845 else if (strcmp(ivmode, "elephant") == 0) { 2846 cc->iv_gen_ops = &crypt_iv_elephant_ops; 2847 cc->key_parts = 2; 2848 cc->key_extra_size = cc->key_size / 2; 2849 if (cc->key_extra_size > ELEPHANT_MAX_KEY_SIZE) 2850 return -EINVAL; 2851 set_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags); 2852 } else if (strcmp(ivmode, "lmk") == 0) { 2853 cc->iv_gen_ops = &crypt_iv_lmk_ops; 2854 /* 2855 * Version 2 and 3 is recognised according 2856 * to length of provided multi-key string. 2857 * If present (version 3), last key is used as IV seed. 2858 * All keys (including IV seed) are always the same size. 2859 */ 2860 if (cc->key_size % cc->key_parts) { 2861 cc->key_parts++; 2862 cc->key_extra_size = cc->key_size / cc->key_parts; 2863 } 2864 } else if (strcmp(ivmode, "tcw") == 0) { 2865 cc->iv_gen_ops = &crypt_iv_tcw_ops; 2866 cc->key_parts += 2; /* IV + whitening */ 2867 cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE; 2868 } else if (strcmp(ivmode, "random") == 0) { 2869 cc->iv_gen_ops = &crypt_iv_random_ops; 2870 /* Need storage space in integrity fields. */ 2871 cc->integrity_iv_size = cc->iv_size; 2872 } else { 2873 ti->error = "Invalid IV mode"; 2874 return -EINVAL; 2875 } 2876 2877 return 0; 2878 } 2879 2880 /* 2881 * Workaround to parse HMAC algorithm from AEAD crypto API spec. 2882 * The HMAC is needed to calculate tag size (HMAC digest size). 2883 * This should be probably done by crypto-api calls (once available...) 2884 */ 2885 static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api) 2886 { 2887 char *start, *end, *mac_alg = NULL; 2888 struct crypto_ahash *mac; 2889 2890 if (!strstarts(cipher_api, "authenc(")) 2891 return 0; 2892 2893 start = strchr(cipher_api, '('); 2894 end = strchr(cipher_api, ','); 2895 if (!start || !end || ++start > end) 2896 return -EINVAL; 2897 2898 mac_alg = kmemdup_nul(start, end - start, GFP_KERNEL); 2899 if (!mac_alg) 2900 return -ENOMEM; 2901 2902 mac = crypto_alloc_ahash(mac_alg, 0, CRYPTO_ALG_ALLOCATES_MEMORY); 2903 kfree(mac_alg); 2904 2905 if (IS_ERR(mac)) 2906 return PTR_ERR(mac); 2907 2908 cc->key_mac_size = crypto_ahash_digestsize(mac); 2909 crypto_free_ahash(mac); 2910 2911 cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL); 2912 if (!cc->authenc_key) 2913 return -ENOMEM; 2914 2915 return 0; 2916 } 2917 2918 static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key, 2919 char **ivmode, char **ivopts) 2920 { 2921 struct crypt_config *cc = ti->private; 2922 char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME]; 2923 int ret = -EINVAL; 2924 2925 cc->tfms_count = 1; 2926 2927 /* 2928 * New format (capi: prefix) 2929 * capi:cipher_api_spec-iv:ivopts 2930 */ 2931 tmp = &cipher_in[strlen("capi:")]; 2932 2933 /* Separate IV options if present, it can contain another '-' in hash name */ 2934 *ivopts = strrchr(tmp, ':'); 2935 if (*ivopts) { 2936 **ivopts = '\0'; 2937 (*ivopts)++; 2938 } 2939 /* Parse IV mode */ 2940 *ivmode = strrchr(tmp, '-'); 2941 if (*ivmode) { 2942 **ivmode = '\0'; 2943 (*ivmode)++; 2944 } 2945 /* The rest is crypto API spec */ 2946 cipher_api = tmp; 2947 2948 /* Alloc AEAD, can be used only in new format. */ 2949 if (crypt_integrity_aead(cc)) { 2950 ret = crypt_ctr_auth_cipher(cc, cipher_api); 2951 if (ret < 0) { 2952 ti->error = "Invalid AEAD cipher spec"; 2953 return ret; 2954 } 2955 } 2956 2957 if (*ivmode && !strcmp(*ivmode, "lmk")) 2958 cc->tfms_count = 64; 2959 2960 if (*ivmode && !strcmp(*ivmode, "essiv")) { 2961 if (!*ivopts) { 2962 ti->error = "Digest algorithm missing for ESSIV mode"; 2963 return -EINVAL; 2964 } 2965 ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)", 2966 cipher_api, *ivopts); 2967 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 2968 ti->error = "Cannot allocate cipher string"; 2969 return -ENOMEM; 2970 } 2971 cipher_api = buf; 2972 } 2973 2974 cc->key_parts = cc->tfms_count; 2975 2976 /* Allocate cipher */ 2977 ret = crypt_alloc_tfms(cc, cipher_api); 2978 if (ret < 0) { 2979 ti->error = "Error allocating crypto tfm"; 2980 return ret; 2981 } 2982 2983 if (crypt_integrity_aead(cc)) 2984 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2985 else 2986 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2987 2988 return 0; 2989 } 2990 2991 static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key, 2992 char **ivmode, char **ivopts) 2993 { 2994 struct crypt_config *cc = ti->private; 2995 char *tmp, *cipher, *chainmode, *keycount; 2996 char *cipher_api = NULL; 2997 int ret = -EINVAL; 2998 char dummy; 2999 3000 if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) { 3001 ti->error = "Bad cipher specification"; 3002 return -EINVAL; 3003 } 3004 3005 /* 3006 * Legacy dm-crypt cipher specification 3007 * cipher[:keycount]-mode-iv:ivopts 3008 */ 3009 tmp = cipher_in; 3010 keycount = strsep(&tmp, "-"); 3011 cipher = strsep(&keycount, ":"); 3012 3013 if (!keycount) 3014 cc->tfms_count = 1; 3015 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 || 3016 !is_power_of_2(cc->tfms_count)) { 3017 ti->error = "Bad cipher key count specification"; 3018 return -EINVAL; 3019 } 3020 cc->key_parts = cc->tfms_count; 3021 3022 chainmode = strsep(&tmp, "-"); 3023 *ivmode = strsep(&tmp, ":"); 3024 *ivopts = tmp; 3025 3026 /* 3027 * For compatibility with the original dm-crypt mapping format, if 3028 * only the cipher name is supplied, use cbc-plain. 3029 */ 3030 if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) { 3031 chainmode = "cbc"; 3032 *ivmode = "plain"; 3033 } 3034 3035 if (strcmp(chainmode, "ecb") && !*ivmode) { 3036 ti->error = "IV mechanism required"; 3037 return -EINVAL; 3038 } 3039 3040 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL); 3041 if (!cipher_api) 3042 goto bad_mem; 3043 3044 if (*ivmode && !strcmp(*ivmode, "essiv")) { 3045 if (!*ivopts) { 3046 ti->error = "Digest algorithm missing for ESSIV mode"; 3047 kfree(cipher_api); 3048 return -EINVAL; 3049 } 3050 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 3051 "essiv(%s(%s),%s)", chainmode, cipher, *ivopts); 3052 } else { 3053 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 3054 "%s(%s)", chainmode, cipher); 3055 } 3056 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 3057 kfree(cipher_api); 3058 goto bad_mem; 3059 } 3060 3061 /* Allocate cipher */ 3062 ret = crypt_alloc_tfms(cc, cipher_api); 3063 if (ret < 0) { 3064 ti->error = "Error allocating crypto tfm"; 3065 kfree(cipher_api); 3066 return ret; 3067 } 3068 kfree(cipher_api); 3069 3070 return 0; 3071 bad_mem: 3072 ti->error = "Cannot allocate cipher strings"; 3073 return -ENOMEM; 3074 } 3075 3076 static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key) 3077 { 3078 struct crypt_config *cc = ti->private; 3079 char *ivmode = NULL, *ivopts = NULL; 3080 int ret; 3081 3082 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL); 3083 if (!cc->cipher_string) { 3084 ti->error = "Cannot allocate cipher strings"; 3085 return -ENOMEM; 3086 } 3087 3088 if (strstarts(cipher_in, "capi:")) 3089 ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts); 3090 else 3091 ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts); 3092 if (ret) 3093 return ret; 3094 3095 /* Initialize IV */ 3096 ret = crypt_ctr_ivmode(ti, ivmode); 3097 if (ret < 0) 3098 return ret; 3099 3100 /* Initialize and set key */ 3101 ret = crypt_set_key(cc, key); 3102 if (ret < 0) { 3103 ti->error = "Error decoding and setting key"; 3104 return ret; 3105 } 3106 3107 /* Allocate IV */ 3108 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) { 3109 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts); 3110 if (ret < 0) { 3111 ti->error = "Error creating IV"; 3112 return ret; 3113 } 3114 } 3115 3116 /* Initialize IV (set keys for ESSIV etc) */ 3117 if (cc->iv_gen_ops && cc->iv_gen_ops->init) { 3118 ret = cc->iv_gen_ops->init(cc); 3119 if (ret < 0) { 3120 ti->error = "Error initialising IV"; 3121 return ret; 3122 } 3123 } 3124 3125 /* wipe the kernel key payload copy */ 3126 if (cc->key_string) 3127 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3128 3129 return ret; 3130 } 3131 3132 static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv) 3133 { 3134 struct crypt_config *cc = ti->private; 3135 struct dm_arg_set as; 3136 static const struct dm_arg _args[] = { 3137 {0, 8, "Invalid number of feature args"}, 3138 }; 3139 unsigned int opt_params, val; 3140 const char *opt_string, *sval; 3141 char dummy; 3142 int ret; 3143 3144 /* Optional parameters */ 3145 as.argc = argc; 3146 as.argv = argv; 3147 3148 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error); 3149 if (ret) 3150 return ret; 3151 3152 while (opt_params--) { 3153 opt_string = dm_shift_arg(&as); 3154 if (!opt_string) { 3155 ti->error = "Not enough feature arguments"; 3156 return -EINVAL; 3157 } 3158 3159 if (!strcasecmp(opt_string, "allow_discards")) 3160 ti->num_discard_bios = 1; 3161 3162 else if (!strcasecmp(opt_string, "same_cpu_crypt")) 3163 set_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3164 3165 else if (!strcasecmp(opt_string, "submit_from_crypt_cpus")) 3166 set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3167 else if (!strcasecmp(opt_string, "no_read_workqueue")) 3168 set_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3169 else if (!strcasecmp(opt_string, "no_write_workqueue")) 3170 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3171 else if (sscanf(opt_string, "integrity:%u:", &val) == 1) { 3172 if (val == 0 || val > MAX_TAG_SIZE) { 3173 ti->error = "Invalid integrity arguments"; 3174 return -EINVAL; 3175 } 3176 cc->on_disk_tag_size = val; 3177 sval = strchr(opt_string + strlen("integrity:"), ':') + 1; 3178 if (!strcasecmp(sval, "aead")) { 3179 set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 3180 } else if (strcasecmp(sval, "none")) { 3181 ti->error = "Unknown integrity profile"; 3182 return -EINVAL; 3183 } 3184 3185 cc->cipher_auth = kstrdup(sval, GFP_KERNEL); 3186 if (!cc->cipher_auth) 3187 return -ENOMEM; 3188 } else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) { 3189 if (cc->sector_size < (1 << SECTOR_SHIFT) || 3190 cc->sector_size > 4096 || 3191 (cc->sector_size & (cc->sector_size - 1))) { 3192 ti->error = "Invalid feature value for sector_size"; 3193 return -EINVAL; 3194 } 3195 if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) { 3196 ti->error = "Device size is not multiple of sector_size feature"; 3197 return -EINVAL; 3198 } 3199 cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT; 3200 } else if (!strcasecmp(opt_string, "iv_large_sectors")) 3201 set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3202 else { 3203 ti->error = "Invalid feature arguments"; 3204 return -EINVAL; 3205 } 3206 } 3207 3208 return 0; 3209 } 3210 3211 #ifdef CONFIG_BLK_DEV_ZONED 3212 static int crypt_report_zones(struct dm_target *ti, 3213 struct dm_report_zones_args *args, unsigned int nr_zones) 3214 { 3215 struct crypt_config *cc = ti->private; 3216 3217 return dm_report_zones(cc->dev->bdev, cc->start, 3218 cc->start + dm_target_offset(ti, args->next_sector), 3219 args, nr_zones); 3220 } 3221 #else 3222 #define crypt_report_zones NULL 3223 #endif 3224 3225 /* 3226 * Construct an encryption mapping: 3227 * <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start> 3228 */ 3229 static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) 3230 { 3231 struct crypt_config *cc; 3232 const char *devname = dm_table_device_name(ti->table); 3233 int key_size; 3234 unsigned int align_mask; 3235 unsigned long long tmpll; 3236 int ret; 3237 size_t iv_size_padding, additional_req_size; 3238 char dummy; 3239 3240 if (argc < 5) { 3241 ti->error = "Not enough arguments"; 3242 return -EINVAL; 3243 } 3244 3245 key_size = get_key_size(&argv[1]); 3246 if (key_size < 0) { 3247 ti->error = "Cannot parse key size"; 3248 return -EINVAL; 3249 } 3250 3251 cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL); 3252 if (!cc) { 3253 ti->error = "Cannot allocate encryption context"; 3254 return -ENOMEM; 3255 } 3256 cc->key_size = key_size; 3257 cc->sector_size = (1 << SECTOR_SHIFT); 3258 cc->sector_shift = 0; 3259 3260 ti->private = cc; 3261 3262 spin_lock(&dm_crypt_clients_lock); 3263 dm_crypt_clients_n++; 3264 crypt_calculate_pages_per_client(); 3265 spin_unlock(&dm_crypt_clients_lock); 3266 3267 ret = percpu_counter_init(&cc->n_allocated_pages, 0, GFP_KERNEL); 3268 if (ret < 0) 3269 goto bad; 3270 3271 /* Optional parameters need to be read before cipher constructor */ 3272 if (argc > 5) { 3273 ret = crypt_ctr_optional(ti, argc - 5, &argv[5]); 3274 if (ret) 3275 goto bad; 3276 } 3277 3278 ret = crypt_ctr_cipher(ti, argv[0], argv[1]); 3279 if (ret < 0) 3280 goto bad; 3281 3282 if (crypt_integrity_aead(cc)) { 3283 cc->dmreq_start = sizeof(struct aead_request); 3284 cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc)); 3285 align_mask = crypto_aead_alignmask(any_tfm_aead(cc)); 3286 } else { 3287 cc->dmreq_start = sizeof(struct skcipher_request); 3288 cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc)); 3289 align_mask = crypto_skcipher_alignmask(any_tfm(cc)); 3290 } 3291 cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request)); 3292 3293 if (align_mask < CRYPTO_MINALIGN) { 3294 /* Allocate the padding exactly */ 3295 iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request)) 3296 & align_mask; 3297 } else { 3298 /* 3299 * If the cipher requires greater alignment than kmalloc 3300 * alignment, we don't know the exact position of the 3301 * initialization vector. We must assume worst case. 3302 */ 3303 iv_size_padding = align_mask; 3304 } 3305 3306 /* ...| IV + padding | original IV | original sec. number | bio tag offset | */ 3307 additional_req_size = sizeof(struct dm_crypt_request) + 3308 iv_size_padding + cc->iv_size + 3309 cc->iv_size + 3310 sizeof(uint64_t) + 3311 sizeof(unsigned int); 3312 3313 ret = mempool_init_kmalloc_pool(&cc->req_pool, MIN_IOS, cc->dmreq_start + additional_req_size); 3314 if (ret) { 3315 ti->error = "Cannot allocate crypt request mempool"; 3316 goto bad; 3317 } 3318 3319 cc->per_bio_data_size = ti->per_io_data_size = 3320 ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size, 3321 ARCH_DMA_MINALIGN); 3322 3323 ret = mempool_init(&cc->page_pool, BIO_MAX_VECS, crypt_page_alloc, crypt_page_free, cc); 3324 if (ret) { 3325 ti->error = "Cannot allocate page mempool"; 3326 goto bad; 3327 } 3328 3329 ret = bioset_init(&cc->bs, MIN_IOS, 0, BIOSET_NEED_BVECS); 3330 if (ret) { 3331 ti->error = "Cannot allocate crypt bioset"; 3332 goto bad; 3333 } 3334 3335 mutex_init(&cc->bio_alloc_lock); 3336 3337 ret = -EINVAL; 3338 if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) || 3339 (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) { 3340 ti->error = "Invalid iv_offset sector"; 3341 goto bad; 3342 } 3343 cc->iv_offset = tmpll; 3344 3345 ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev); 3346 if (ret) { 3347 ti->error = "Device lookup failed"; 3348 goto bad; 3349 } 3350 3351 ret = -EINVAL; 3352 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) { 3353 ti->error = "Invalid device sector"; 3354 goto bad; 3355 } 3356 cc->start = tmpll; 3357 3358 if (bdev_is_zoned(cc->dev->bdev)) { 3359 /* 3360 * For zoned block devices, we need to preserve the issuer write 3361 * ordering. To do so, disable write workqueues and force inline 3362 * encryption completion. 3363 */ 3364 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3365 set_bit(DM_CRYPT_WRITE_INLINE, &cc->flags); 3366 3367 /* 3368 * All zone append writes to a zone of a zoned block device will 3369 * have the same BIO sector, the start of the zone. When the 3370 * cypher IV mode uses sector values, all data targeting a 3371 * zone will be encrypted using the first sector numbers of the 3372 * zone. This will not result in write errors but will 3373 * cause most reads to fail as reads will use the sector values 3374 * for the actual data locations, resulting in IV mismatch. 3375 * To avoid this problem, ask DM core to emulate zone append 3376 * operations with regular writes. 3377 */ 3378 DMDEBUG("Zone append operations will be emulated"); 3379 ti->emulate_zone_append = true; 3380 } 3381 3382 if (crypt_integrity_aead(cc) || cc->integrity_iv_size) { 3383 ret = crypt_integrity_ctr(cc, ti); 3384 if (ret) 3385 goto bad; 3386 3387 cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->on_disk_tag_size; 3388 if (!cc->tag_pool_max_sectors) 3389 cc->tag_pool_max_sectors = 1; 3390 3391 ret = mempool_init_kmalloc_pool(&cc->tag_pool, MIN_IOS, 3392 cc->tag_pool_max_sectors * cc->on_disk_tag_size); 3393 if (ret) { 3394 ti->error = "Cannot allocate integrity tags mempool"; 3395 goto bad; 3396 } 3397 3398 cc->tag_pool_max_sectors <<= cc->sector_shift; 3399 } 3400 3401 ret = -ENOMEM; 3402 cc->io_queue = alloc_workqueue("kcryptd_io/%s", WQ_MEM_RECLAIM, 1, devname); 3403 if (!cc->io_queue) { 3404 ti->error = "Couldn't create kcryptd io queue"; 3405 goto bad; 3406 } 3407 3408 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3409 cc->crypt_queue = alloc_workqueue("kcryptd/%s", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 3410 1, devname); 3411 else 3412 cc->crypt_queue = alloc_workqueue("kcryptd/%s", 3413 WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND, 3414 num_online_cpus(), devname); 3415 if (!cc->crypt_queue) { 3416 ti->error = "Couldn't create kcryptd queue"; 3417 goto bad; 3418 } 3419 3420 spin_lock_init(&cc->write_thread_lock); 3421 cc->write_tree = RB_ROOT; 3422 3423 cc->write_thread = kthread_run(dmcrypt_write, cc, "dmcrypt_write/%s", devname); 3424 if (IS_ERR(cc->write_thread)) { 3425 ret = PTR_ERR(cc->write_thread); 3426 cc->write_thread = NULL; 3427 ti->error = "Couldn't spawn write thread"; 3428 goto bad; 3429 } 3430 3431 ti->num_flush_bios = 1; 3432 ti->limit_swap_bios = true; 3433 ti->accounts_remapped_io = true; 3434 3435 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 1); 3436 return 0; 3437 3438 bad: 3439 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 0); 3440 crypt_dtr(ti); 3441 return ret; 3442 } 3443 3444 static int crypt_map(struct dm_target *ti, struct bio *bio) 3445 { 3446 struct dm_crypt_io *io; 3447 struct crypt_config *cc = ti->private; 3448 3449 /* 3450 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues. 3451 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight 3452 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters 3453 */ 3454 if (unlikely(bio->bi_opf & REQ_PREFLUSH || 3455 bio_op(bio) == REQ_OP_DISCARD)) { 3456 bio_set_dev(bio, cc->dev->bdev); 3457 if (bio_sectors(bio)) 3458 bio->bi_iter.bi_sector = cc->start + 3459 dm_target_offset(ti, bio->bi_iter.bi_sector); 3460 return DM_MAPIO_REMAPPED; 3461 } 3462 3463 /* 3464 * Check if bio is too large, split as needed. 3465 */ 3466 if (unlikely(bio->bi_iter.bi_size > (BIO_MAX_VECS << PAGE_SHIFT)) && 3467 (bio_data_dir(bio) == WRITE || cc->on_disk_tag_size)) 3468 dm_accept_partial_bio(bio, ((BIO_MAX_VECS << PAGE_SHIFT) >> SECTOR_SHIFT)); 3469 3470 /* 3471 * Ensure that bio is a multiple of internal sector encryption size 3472 * and is aligned to this size as defined in IO hints. 3473 */ 3474 if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0)) 3475 return DM_MAPIO_KILL; 3476 3477 if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1))) 3478 return DM_MAPIO_KILL; 3479 3480 io = dm_per_bio_data(bio, cc->per_bio_data_size); 3481 crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector)); 3482 3483 if (cc->on_disk_tag_size) { 3484 unsigned int tag_len = cc->on_disk_tag_size * (bio_sectors(bio) >> cc->sector_shift); 3485 3486 if (unlikely(tag_len > KMALLOC_MAX_SIZE)) 3487 io->integrity_metadata = NULL; 3488 else 3489 io->integrity_metadata = kmalloc(tag_len, GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN); 3490 3491 if (unlikely(!io->integrity_metadata)) { 3492 if (bio_sectors(bio) > cc->tag_pool_max_sectors) 3493 dm_accept_partial_bio(bio, cc->tag_pool_max_sectors); 3494 io->integrity_metadata = mempool_alloc(&cc->tag_pool, GFP_NOIO); 3495 io->integrity_metadata_from_pool = true; 3496 } 3497 } 3498 3499 if (crypt_integrity_aead(cc)) 3500 io->ctx.r.req_aead = (struct aead_request *)(io + 1); 3501 else 3502 io->ctx.r.req = (struct skcipher_request *)(io + 1); 3503 3504 if (bio_data_dir(io->base_bio) == READ) { 3505 if (kcryptd_io_read(io, CRYPT_MAP_READ_GFP)) 3506 kcryptd_queue_read(io); 3507 } else 3508 kcryptd_queue_crypt(io); 3509 3510 return DM_MAPIO_SUBMITTED; 3511 } 3512 3513 static char hex2asc(unsigned char c) 3514 { 3515 return c + '0' + ((unsigned int)(9 - c) >> 4 & 0x27); 3516 } 3517 3518 static void crypt_status(struct dm_target *ti, status_type_t type, 3519 unsigned int status_flags, char *result, unsigned int maxlen) 3520 { 3521 struct crypt_config *cc = ti->private; 3522 unsigned int i, sz = 0; 3523 int num_feature_args = 0; 3524 3525 switch (type) { 3526 case STATUSTYPE_INFO: 3527 result[0] = '\0'; 3528 break; 3529 3530 case STATUSTYPE_TABLE: 3531 DMEMIT("%s ", cc->cipher_string); 3532 3533 if (cc->key_size > 0) { 3534 if (cc->key_string) 3535 DMEMIT(":%u:%s", cc->key_size, cc->key_string); 3536 else { 3537 for (i = 0; i < cc->key_size; i++) { 3538 DMEMIT("%c%c", hex2asc(cc->key[i] >> 4), 3539 hex2asc(cc->key[i] & 0xf)); 3540 } 3541 } 3542 } else 3543 DMEMIT("-"); 3544 3545 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, 3546 cc->dev->name, (unsigned long long)cc->start); 3547 3548 num_feature_args += !!ti->num_discard_bios; 3549 num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3550 num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3551 num_feature_args += test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3552 num_feature_args += test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3553 num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT); 3554 num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3555 if (cc->on_disk_tag_size) 3556 num_feature_args++; 3557 if (num_feature_args) { 3558 DMEMIT(" %d", num_feature_args); 3559 if (ti->num_discard_bios) 3560 DMEMIT(" allow_discards"); 3561 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3562 DMEMIT(" same_cpu_crypt"); 3563 if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) 3564 DMEMIT(" submit_from_crypt_cpus"); 3565 if (test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) 3566 DMEMIT(" no_read_workqueue"); 3567 if (test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) 3568 DMEMIT(" no_write_workqueue"); 3569 if (cc->on_disk_tag_size) 3570 DMEMIT(" integrity:%u:%s", cc->on_disk_tag_size, cc->cipher_auth); 3571 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3572 DMEMIT(" sector_size:%d", cc->sector_size); 3573 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 3574 DMEMIT(" iv_large_sectors"); 3575 } 3576 break; 3577 3578 case STATUSTYPE_IMA: 3579 DMEMIT_TARGET_NAME_VERSION(ti->type); 3580 DMEMIT(",allow_discards=%c", ti->num_discard_bios ? 'y' : 'n'); 3581 DMEMIT(",same_cpu_crypt=%c", test_bit(DM_CRYPT_SAME_CPU, &cc->flags) ? 'y' : 'n'); 3582 DMEMIT(",submit_from_crypt_cpus=%c", test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags) ? 3583 'y' : 'n'); 3584 DMEMIT(",no_read_workqueue=%c", test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags) ? 3585 'y' : 'n'); 3586 DMEMIT(",no_write_workqueue=%c", test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags) ? 3587 'y' : 'n'); 3588 DMEMIT(",iv_large_sectors=%c", test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags) ? 3589 'y' : 'n'); 3590 3591 if (cc->on_disk_tag_size) 3592 DMEMIT(",integrity_tag_size=%u,cipher_auth=%s", 3593 cc->on_disk_tag_size, cc->cipher_auth); 3594 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3595 DMEMIT(",sector_size=%d", cc->sector_size); 3596 if (cc->cipher_string) 3597 DMEMIT(",cipher_string=%s", cc->cipher_string); 3598 3599 DMEMIT(",key_size=%u", cc->key_size); 3600 DMEMIT(",key_parts=%u", cc->key_parts); 3601 DMEMIT(",key_extra_size=%u", cc->key_extra_size); 3602 DMEMIT(",key_mac_size=%u", cc->key_mac_size); 3603 DMEMIT(";"); 3604 break; 3605 } 3606 } 3607 3608 static void crypt_postsuspend(struct dm_target *ti) 3609 { 3610 struct crypt_config *cc = ti->private; 3611 3612 set_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3613 } 3614 3615 static int crypt_preresume(struct dm_target *ti) 3616 { 3617 struct crypt_config *cc = ti->private; 3618 3619 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { 3620 DMERR("aborting resume - crypt key is not set."); 3621 return -EAGAIN; 3622 } 3623 3624 return 0; 3625 } 3626 3627 static void crypt_resume(struct dm_target *ti) 3628 { 3629 struct crypt_config *cc = ti->private; 3630 3631 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3632 } 3633 3634 /* Message interface 3635 * key set <key> 3636 * key wipe 3637 */ 3638 static int crypt_message(struct dm_target *ti, unsigned int argc, char **argv, 3639 char *result, unsigned int maxlen) 3640 { 3641 struct crypt_config *cc = ti->private; 3642 int key_size, ret = -EINVAL; 3643 3644 if (argc < 2) 3645 goto error; 3646 3647 if (!strcasecmp(argv[0], "key")) { 3648 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { 3649 DMWARN("not suspended during key manipulation."); 3650 return -EINVAL; 3651 } 3652 if (argc == 3 && !strcasecmp(argv[1], "set")) { 3653 /* The key size may not be changed. */ 3654 key_size = get_key_size(&argv[2]); 3655 if (key_size < 0 || cc->key_size != key_size) { 3656 memset(argv[2], '0', strlen(argv[2])); 3657 return -EINVAL; 3658 } 3659 3660 ret = crypt_set_key(cc, argv[2]); 3661 if (ret) 3662 return ret; 3663 if (cc->iv_gen_ops && cc->iv_gen_ops->init) 3664 ret = cc->iv_gen_ops->init(cc); 3665 /* wipe the kernel key payload copy */ 3666 if (cc->key_string) 3667 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3668 return ret; 3669 } 3670 if (argc == 2 && !strcasecmp(argv[1], "wipe")) 3671 return crypt_wipe_key(cc); 3672 } 3673 3674 error: 3675 DMWARN("unrecognised message received."); 3676 return -EINVAL; 3677 } 3678 3679 static int crypt_iterate_devices(struct dm_target *ti, 3680 iterate_devices_callout_fn fn, void *data) 3681 { 3682 struct crypt_config *cc = ti->private; 3683 3684 return fn(ti, cc->dev, cc->start, ti->len, data); 3685 } 3686 3687 static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits) 3688 { 3689 struct crypt_config *cc = ti->private; 3690 3691 /* 3692 * Unfortunate constraint that is required to avoid the potential 3693 * for exceeding underlying device's max_segments limits -- due to 3694 * crypt_alloc_buffer() possibly allocating pages for the encryption 3695 * bio that are not as physically contiguous as the original bio. 3696 */ 3697 limits->max_segment_size = PAGE_SIZE; 3698 3699 limits->logical_block_size = 3700 max_t(unsigned int, limits->logical_block_size, cc->sector_size); 3701 limits->physical_block_size = 3702 max_t(unsigned int, limits->physical_block_size, cc->sector_size); 3703 limits->io_min = max_t(unsigned int, limits->io_min, cc->sector_size); 3704 limits->dma_alignment = limits->logical_block_size - 1; 3705 } 3706 3707 static struct target_type crypt_target = { 3708 .name = "crypt", 3709 .version = {1, 25, 0}, 3710 .module = THIS_MODULE, 3711 .ctr = crypt_ctr, 3712 .dtr = crypt_dtr, 3713 .features = DM_TARGET_ZONED_HM, 3714 .report_zones = crypt_report_zones, 3715 .map = crypt_map, 3716 .status = crypt_status, 3717 .postsuspend = crypt_postsuspend, 3718 .preresume = crypt_preresume, 3719 .resume = crypt_resume, 3720 .message = crypt_message, 3721 .iterate_devices = crypt_iterate_devices, 3722 .io_hints = crypt_io_hints, 3723 }; 3724 module_dm(crypt); 3725 3726 MODULE_AUTHOR("Jana Saout <jana@saout.de>"); 3727 MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); 3728 MODULE_LICENSE("GPL"); 3729