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