1 /* 2 * Copyright (C) 2003 Jana Saout <jana@saout.de> 3 * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org> 4 * Copyright (C) 2006-2020 Red Hat, Inc. All rights reserved. 5 * Copyright (C) 2013-2020 Milan Broz <gmazyland@gmail.com> 6 * 7 * This file is released under the GPL. 8 */ 9 10 #include <linux/completion.h> 11 #include <linux/err.h> 12 #include <linux/module.h> 13 #include <linux/init.h> 14 #include <linux/kernel.h> 15 #include <linux/key.h> 16 #include <linux/bio.h> 17 #include <linux/blkdev.h> 18 #include <linux/mempool.h> 19 #include <linux/slab.h> 20 #include <linux/crypto.h> 21 #include <linux/workqueue.h> 22 #include <linux/kthread.h> 23 #include <linux/backing-dev.h> 24 #include <linux/atomic.h> 25 #include <linux/scatterlist.h> 26 #include <linux/rbtree.h> 27 #include <linux/ctype.h> 28 #include <asm/page.h> 29 #include <asm/unaligned.h> 30 #include <crypto/hash.h> 31 #include <crypto/md5.h> 32 #include <crypto/algapi.h> 33 #include <crypto/skcipher.h> 34 #include <crypto/aead.h> 35 #include <crypto/authenc.h> 36 #include <linux/rtnetlink.h> /* for struct rtattr and RTA macros only */ 37 #include <linux/key-type.h> 38 #include <keys/user-type.h> 39 #include <keys/encrypted-type.h> 40 41 #include <linux/device-mapper.h> 42 43 #define DM_MSG_PREFIX "crypt" 44 45 /* 46 * context holding the current state of a multi-part conversion 47 */ 48 struct convert_context { 49 struct completion restart; 50 struct bio *bio_in; 51 struct bio *bio_out; 52 struct bvec_iter iter_in; 53 struct bvec_iter iter_out; 54 u64 cc_sector; 55 atomic_t cc_pending; 56 union { 57 struct skcipher_request *req; 58 struct aead_request *req_aead; 59 } r; 60 61 }; 62 63 /* 64 * per bio private data 65 */ 66 struct dm_crypt_io { 67 struct crypt_config *cc; 68 struct bio *base_bio; 69 u8 *integrity_metadata; 70 bool integrity_metadata_from_pool; 71 struct work_struct work; 72 struct tasklet_struct tasklet; 73 74 struct convert_context ctx; 75 76 atomic_t io_pending; 77 blk_status_t error; 78 sector_t sector; 79 80 struct rb_node rb_node; 81 } CRYPTO_MINALIGN_ATTR; 82 83 struct dm_crypt_request { 84 struct convert_context *ctx; 85 struct scatterlist sg_in[4]; 86 struct scatterlist sg_out[4]; 87 u64 iv_sector; 88 }; 89 90 struct crypt_config; 91 92 struct crypt_iv_operations { 93 int (*ctr)(struct crypt_config *cc, struct dm_target *ti, 94 const char *opts); 95 void (*dtr)(struct crypt_config *cc); 96 int (*init)(struct crypt_config *cc); 97 int (*wipe)(struct crypt_config *cc); 98 int (*generator)(struct crypt_config *cc, u8 *iv, 99 struct dm_crypt_request *dmreq); 100 int (*post)(struct crypt_config *cc, u8 *iv, 101 struct dm_crypt_request *dmreq); 102 }; 103 104 struct iv_benbi_private { 105 int shift; 106 }; 107 108 #define LMK_SEED_SIZE 64 /* hash + 0 */ 109 struct iv_lmk_private { 110 struct crypto_shash *hash_tfm; 111 u8 *seed; 112 }; 113 114 #define TCW_WHITENING_SIZE 16 115 struct iv_tcw_private { 116 struct crypto_shash *crc32_tfm; 117 u8 *iv_seed; 118 u8 *whitening; 119 }; 120 121 #define ELEPHANT_MAX_KEY_SIZE 32 122 struct iv_elephant_private { 123 struct crypto_skcipher *tfm; 124 }; 125 126 /* 127 * Crypt: maps a linear range of a block device 128 * and encrypts / decrypts at the same time. 129 */ 130 enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID, 131 DM_CRYPT_SAME_CPU, DM_CRYPT_NO_OFFLOAD, 132 DM_CRYPT_NO_READ_WORKQUEUE, DM_CRYPT_NO_WRITE_WORKQUEUE, 133 DM_CRYPT_WRITE_INLINE }; 134 135 enum cipher_flags { 136 CRYPT_MODE_INTEGRITY_AEAD, /* Use authenticated mode for cihper */ 137 CRYPT_IV_LARGE_SECTORS, /* Calculate IV from sector_size, not 512B sectors */ 138 CRYPT_ENCRYPT_PREPROCESS, /* Must preprocess data for encryption (elephant) */ 139 }; 140 141 /* 142 * The fields in here must be read only after initialization. 143 */ 144 struct crypt_config { 145 struct dm_dev *dev; 146 sector_t start; 147 148 struct percpu_counter n_allocated_pages; 149 150 struct workqueue_struct *io_queue; 151 struct workqueue_struct *crypt_queue; 152 153 spinlock_t write_thread_lock; 154 struct task_struct *write_thread; 155 struct rb_root write_tree; 156 157 char *cipher_string; 158 char *cipher_auth; 159 char *key_string; 160 161 const struct crypt_iv_operations *iv_gen_ops; 162 union { 163 struct iv_benbi_private benbi; 164 struct iv_lmk_private lmk; 165 struct iv_tcw_private tcw; 166 struct iv_elephant_private elephant; 167 } iv_gen_private; 168 u64 iv_offset; 169 unsigned int iv_size; 170 unsigned short int sector_size; 171 unsigned char sector_shift; 172 173 union { 174 struct crypto_skcipher **tfms; 175 struct crypto_aead **tfms_aead; 176 } cipher_tfm; 177 unsigned tfms_count; 178 unsigned long cipher_flags; 179 180 /* 181 * Layout of each crypto request: 182 * 183 * struct skcipher_request 184 * context 185 * padding 186 * struct dm_crypt_request 187 * padding 188 * IV 189 * 190 * The padding is added so that dm_crypt_request and the IV are 191 * correctly aligned. 192 */ 193 unsigned int dmreq_start; 194 195 unsigned int per_bio_data_size; 196 197 unsigned long flags; 198 unsigned int key_size; 199 unsigned int key_parts; /* independent parts in key buffer */ 200 unsigned int key_extra_size; /* additional keys length */ 201 unsigned int key_mac_size; /* MAC key size for authenc(...) */ 202 203 unsigned int integrity_tag_size; 204 unsigned int integrity_iv_size; 205 unsigned int on_disk_tag_size; 206 207 /* 208 * pool for per bio private data, crypto requests, 209 * encryption requeusts/buffer pages and integrity tags 210 */ 211 unsigned tag_pool_max_sectors; 212 mempool_t tag_pool; 213 mempool_t req_pool; 214 mempool_t page_pool; 215 216 struct bio_set bs; 217 struct mutex bio_alloc_lock; 218 219 u8 *authenc_key; /* space for keys in authenc() format (if used) */ 220 u8 key[]; 221 }; 222 223 #define MIN_IOS 64 224 #define MAX_TAG_SIZE 480 225 #define POOL_ENTRY_SIZE 512 226 227 static DEFINE_SPINLOCK(dm_crypt_clients_lock); 228 static unsigned dm_crypt_clients_n = 0; 229 static volatile unsigned long dm_crypt_pages_per_client; 230 #define DM_CRYPT_MEMORY_PERCENT 2 231 #define DM_CRYPT_MIN_PAGES_PER_CLIENT (BIO_MAX_PAGES * 16) 232 233 static void clone_init(struct dm_crypt_io *, struct bio *); 234 static void kcryptd_queue_crypt(struct dm_crypt_io *io); 235 static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 236 struct scatterlist *sg); 237 238 static bool crypt_integrity_aead(struct crypt_config *cc); 239 240 /* 241 * Use this to access cipher attributes that are independent of the key. 242 */ 243 static struct crypto_skcipher *any_tfm(struct crypt_config *cc) 244 { 245 return cc->cipher_tfm.tfms[0]; 246 } 247 248 static struct crypto_aead *any_tfm_aead(struct crypt_config *cc) 249 { 250 return cc->cipher_tfm.tfms_aead[0]; 251 } 252 253 /* 254 * Different IV generation algorithms: 255 * 256 * plain: the initial vector is the 32-bit little-endian version of the sector 257 * number, padded with zeros if necessary. 258 * 259 * plain64: the initial vector is the 64-bit little-endian version of the sector 260 * number, padded with zeros if necessary. 261 * 262 * plain64be: the initial vector is the 64-bit big-endian version of the sector 263 * number, padded with zeros if necessary. 264 * 265 * essiv: "encrypted sector|salt initial vector", the sector number is 266 * encrypted with the bulk cipher using a salt as key. The salt 267 * should be derived from the bulk cipher's key via hashing. 268 * 269 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 270 * (needed for LRW-32-AES and possible other narrow block modes) 271 * 272 * null: the initial vector is always zero. Provides compatibility with 273 * obsolete loop_fish2 devices. Do not use for new devices. 274 * 275 * lmk: Compatible implementation of the block chaining mode used 276 * by the Loop-AES block device encryption system 277 * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/ 278 * It operates on full 512 byte sectors and uses CBC 279 * with an IV derived from the sector number, the data and 280 * optionally extra IV seed. 281 * This means that after decryption the first block 282 * of sector must be tweaked according to decrypted data. 283 * Loop-AES can use three encryption schemes: 284 * version 1: is plain aes-cbc mode 285 * version 2: uses 64 multikey scheme with lmk IV generator 286 * version 3: the same as version 2 with additional IV seed 287 * (it uses 65 keys, last key is used as IV seed) 288 * 289 * tcw: Compatible implementation of the block chaining mode used 290 * by the TrueCrypt device encryption system (prior to version 4.1). 291 * For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat 292 * It operates on full 512 byte sectors and uses CBC 293 * with an IV derived from initial key and the sector number. 294 * In addition, whitening value is applied on every sector, whitening 295 * is calculated from initial key, sector number and mixed using CRC32. 296 * Note that this encryption scheme is vulnerable to watermarking attacks 297 * and should be used for old compatible containers access only. 298 * 299 * eboiv: Encrypted byte-offset IV (used in Bitlocker in CBC mode) 300 * The IV is encrypted little-endian byte-offset (with the same key 301 * and cipher as the volume). 302 * 303 * elephant: The extended version of eboiv with additional Elephant diffuser 304 * used with Bitlocker CBC mode. 305 * This mode was used in older Windows systems 306 * https://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf 307 */ 308 309 static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, 310 struct dm_crypt_request *dmreq) 311 { 312 memset(iv, 0, cc->iv_size); 313 *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff); 314 315 return 0; 316 } 317 318 static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv, 319 struct dm_crypt_request *dmreq) 320 { 321 memset(iv, 0, cc->iv_size); 322 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 323 324 return 0; 325 } 326 327 static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv, 328 struct dm_crypt_request *dmreq) 329 { 330 memset(iv, 0, cc->iv_size); 331 /* iv_size is at least of size u64; usually it is 16 bytes */ 332 *(__be64 *)&iv[cc->iv_size - sizeof(u64)] = cpu_to_be64(dmreq->iv_sector); 333 334 return 0; 335 } 336 337 static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, 338 struct dm_crypt_request *dmreq) 339 { 340 /* 341 * ESSIV encryption of the IV is now handled by the crypto API, 342 * so just pass the plain sector number here. 343 */ 344 memset(iv, 0, cc->iv_size); 345 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 346 347 return 0; 348 } 349 350 static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, 351 const char *opts) 352 { 353 unsigned bs; 354 int log; 355 356 if (crypt_integrity_aead(cc)) 357 bs = crypto_aead_blocksize(any_tfm_aead(cc)); 358 else 359 bs = crypto_skcipher_blocksize(any_tfm(cc)); 360 log = ilog2(bs); 361 362 /* we need to calculate how far we must shift the sector count 363 * to get the cipher block count, we use this shift in _gen */ 364 365 if (1 << log != bs) { 366 ti->error = "cypher blocksize is not a power of 2"; 367 return -EINVAL; 368 } 369 370 if (log > 9) { 371 ti->error = "cypher blocksize is > 512"; 372 return -EINVAL; 373 } 374 375 cc->iv_gen_private.benbi.shift = 9 - log; 376 377 return 0; 378 } 379 380 static void crypt_iv_benbi_dtr(struct crypt_config *cc) 381 { 382 } 383 384 static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, 385 struct dm_crypt_request *dmreq) 386 { 387 __be64 val; 388 389 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ 390 391 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1); 392 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); 393 394 return 0; 395 } 396 397 static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, 398 struct dm_crypt_request *dmreq) 399 { 400 memset(iv, 0, cc->iv_size); 401 402 return 0; 403 } 404 405 static void crypt_iv_lmk_dtr(struct crypt_config *cc) 406 { 407 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 408 409 if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm)) 410 crypto_free_shash(lmk->hash_tfm); 411 lmk->hash_tfm = NULL; 412 413 kfree_sensitive(lmk->seed); 414 lmk->seed = NULL; 415 } 416 417 static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti, 418 const char *opts) 419 { 420 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 421 422 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 423 ti->error = "Unsupported sector size for LMK"; 424 return -EINVAL; 425 } 426 427 lmk->hash_tfm = crypto_alloc_shash("md5", 0, 428 CRYPTO_ALG_ALLOCATES_MEMORY); 429 if (IS_ERR(lmk->hash_tfm)) { 430 ti->error = "Error initializing LMK hash"; 431 return PTR_ERR(lmk->hash_tfm); 432 } 433 434 /* No seed in LMK version 2 */ 435 if (cc->key_parts == cc->tfms_count) { 436 lmk->seed = NULL; 437 return 0; 438 } 439 440 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL); 441 if (!lmk->seed) { 442 crypt_iv_lmk_dtr(cc); 443 ti->error = "Error kmallocing seed storage in LMK"; 444 return -ENOMEM; 445 } 446 447 return 0; 448 } 449 450 static int crypt_iv_lmk_init(struct crypt_config *cc) 451 { 452 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 453 int subkey_size = cc->key_size / cc->key_parts; 454 455 /* LMK seed is on the position of LMK_KEYS + 1 key */ 456 if (lmk->seed) 457 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size), 458 crypto_shash_digestsize(lmk->hash_tfm)); 459 460 return 0; 461 } 462 463 static int crypt_iv_lmk_wipe(struct crypt_config *cc) 464 { 465 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 466 467 if (lmk->seed) 468 memset(lmk->seed, 0, LMK_SEED_SIZE); 469 470 return 0; 471 } 472 473 static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv, 474 struct dm_crypt_request *dmreq, 475 u8 *data) 476 { 477 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 478 SHASH_DESC_ON_STACK(desc, lmk->hash_tfm); 479 struct md5_state md5state; 480 __le32 buf[4]; 481 int i, r; 482 483 desc->tfm = lmk->hash_tfm; 484 485 r = crypto_shash_init(desc); 486 if (r) 487 return r; 488 489 if (lmk->seed) { 490 r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE); 491 if (r) 492 return r; 493 } 494 495 /* Sector is always 512B, block size 16, add data of blocks 1-31 */ 496 r = crypto_shash_update(desc, data + 16, 16 * 31); 497 if (r) 498 return r; 499 500 /* Sector is cropped to 56 bits here */ 501 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF); 502 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000); 503 buf[2] = cpu_to_le32(4024); 504 buf[3] = 0; 505 r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf)); 506 if (r) 507 return r; 508 509 /* No MD5 padding here */ 510 r = crypto_shash_export(desc, &md5state); 511 if (r) 512 return r; 513 514 for (i = 0; i < MD5_HASH_WORDS; i++) 515 __cpu_to_le32s(&md5state.hash[i]); 516 memcpy(iv, &md5state.hash, cc->iv_size); 517 518 return 0; 519 } 520 521 static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv, 522 struct dm_crypt_request *dmreq) 523 { 524 struct scatterlist *sg; 525 u8 *src; 526 int r = 0; 527 528 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 529 sg = crypt_get_sg_data(cc, dmreq->sg_in); 530 src = kmap_atomic(sg_page(sg)); 531 r = crypt_iv_lmk_one(cc, iv, dmreq, src + sg->offset); 532 kunmap_atomic(src); 533 } else 534 memset(iv, 0, cc->iv_size); 535 536 return r; 537 } 538 539 static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv, 540 struct dm_crypt_request *dmreq) 541 { 542 struct scatterlist *sg; 543 u8 *dst; 544 int r; 545 546 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) 547 return 0; 548 549 sg = crypt_get_sg_data(cc, dmreq->sg_out); 550 dst = kmap_atomic(sg_page(sg)); 551 r = crypt_iv_lmk_one(cc, iv, dmreq, dst + sg->offset); 552 553 /* Tweak the first block of plaintext sector */ 554 if (!r) 555 crypto_xor(dst + sg->offset, iv, cc->iv_size); 556 557 kunmap_atomic(dst); 558 return r; 559 } 560 561 static void crypt_iv_tcw_dtr(struct crypt_config *cc) 562 { 563 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 564 565 kfree_sensitive(tcw->iv_seed); 566 tcw->iv_seed = NULL; 567 kfree_sensitive(tcw->whitening); 568 tcw->whitening = NULL; 569 570 if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm)) 571 crypto_free_shash(tcw->crc32_tfm); 572 tcw->crc32_tfm = NULL; 573 } 574 575 static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti, 576 const char *opts) 577 { 578 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 579 580 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 581 ti->error = "Unsupported sector size for TCW"; 582 return -EINVAL; 583 } 584 585 if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) { 586 ti->error = "Wrong key size for TCW"; 587 return -EINVAL; 588 } 589 590 tcw->crc32_tfm = crypto_alloc_shash("crc32", 0, 591 CRYPTO_ALG_ALLOCATES_MEMORY); 592 if (IS_ERR(tcw->crc32_tfm)) { 593 ti->error = "Error initializing CRC32 in TCW"; 594 return PTR_ERR(tcw->crc32_tfm); 595 } 596 597 tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL); 598 tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL); 599 if (!tcw->iv_seed || !tcw->whitening) { 600 crypt_iv_tcw_dtr(cc); 601 ti->error = "Error allocating seed storage in TCW"; 602 return -ENOMEM; 603 } 604 605 return 0; 606 } 607 608 static int crypt_iv_tcw_init(struct crypt_config *cc) 609 { 610 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 611 int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE; 612 613 memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size); 614 memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size], 615 TCW_WHITENING_SIZE); 616 617 return 0; 618 } 619 620 static int crypt_iv_tcw_wipe(struct crypt_config *cc) 621 { 622 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 623 624 memset(tcw->iv_seed, 0, cc->iv_size); 625 memset(tcw->whitening, 0, TCW_WHITENING_SIZE); 626 627 return 0; 628 } 629 630 static int crypt_iv_tcw_whitening(struct crypt_config *cc, 631 struct dm_crypt_request *dmreq, 632 u8 *data) 633 { 634 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 635 __le64 sector = cpu_to_le64(dmreq->iv_sector); 636 u8 buf[TCW_WHITENING_SIZE]; 637 SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm); 638 int i, r; 639 640 /* xor whitening with sector number */ 641 crypto_xor_cpy(buf, tcw->whitening, (u8 *)§or, 8); 642 crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)§or, 8); 643 644 /* calculate crc32 for every 32bit part and xor it */ 645 desc->tfm = tcw->crc32_tfm; 646 for (i = 0; i < 4; i++) { 647 r = crypto_shash_init(desc); 648 if (r) 649 goto out; 650 r = crypto_shash_update(desc, &buf[i * 4], 4); 651 if (r) 652 goto out; 653 r = crypto_shash_final(desc, &buf[i * 4]); 654 if (r) 655 goto out; 656 } 657 crypto_xor(&buf[0], &buf[12], 4); 658 crypto_xor(&buf[4], &buf[8], 4); 659 660 /* apply whitening (8 bytes) to whole sector */ 661 for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++) 662 crypto_xor(data + i * 8, buf, 8); 663 out: 664 memzero_explicit(buf, sizeof(buf)); 665 return r; 666 } 667 668 static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv, 669 struct dm_crypt_request *dmreq) 670 { 671 struct scatterlist *sg; 672 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 673 __le64 sector = cpu_to_le64(dmreq->iv_sector); 674 u8 *src; 675 int r = 0; 676 677 /* Remove whitening from ciphertext */ 678 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 679 sg = crypt_get_sg_data(cc, dmreq->sg_in); 680 src = kmap_atomic(sg_page(sg)); 681 r = crypt_iv_tcw_whitening(cc, dmreq, src + sg->offset); 682 kunmap_atomic(src); 683 } 684 685 /* Calculate IV */ 686 crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)§or, 8); 687 if (cc->iv_size > 8) 688 crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)§or, 689 cc->iv_size - 8); 690 691 return r; 692 } 693 694 static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv, 695 struct dm_crypt_request *dmreq) 696 { 697 struct scatterlist *sg; 698 u8 *dst; 699 int r; 700 701 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 702 return 0; 703 704 /* Apply whitening on ciphertext */ 705 sg = crypt_get_sg_data(cc, dmreq->sg_out); 706 dst = kmap_atomic(sg_page(sg)); 707 r = crypt_iv_tcw_whitening(cc, dmreq, dst + sg->offset); 708 kunmap_atomic(dst); 709 710 return r; 711 } 712 713 static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv, 714 struct dm_crypt_request *dmreq) 715 { 716 /* Used only for writes, there must be an additional space to store IV */ 717 get_random_bytes(iv, cc->iv_size); 718 return 0; 719 } 720 721 static int crypt_iv_eboiv_ctr(struct crypt_config *cc, struct dm_target *ti, 722 const char *opts) 723 { 724 if (crypt_integrity_aead(cc)) { 725 ti->error = "AEAD transforms not supported for EBOIV"; 726 return -EINVAL; 727 } 728 729 if (crypto_skcipher_blocksize(any_tfm(cc)) != cc->iv_size) { 730 ti->error = "Block size of EBOIV cipher does " 731 "not match IV size of block cipher"; 732 return -EINVAL; 733 } 734 735 return 0; 736 } 737 738 static int crypt_iv_eboiv_gen(struct crypt_config *cc, u8 *iv, 739 struct dm_crypt_request *dmreq) 740 { 741 u8 buf[MAX_CIPHER_BLOCKSIZE] __aligned(__alignof__(__le64)); 742 struct skcipher_request *req; 743 struct scatterlist src, dst; 744 DECLARE_CRYPTO_WAIT(wait); 745 int err; 746 747 req = skcipher_request_alloc(any_tfm(cc), GFP_NOIO); 748 if (!req) 749 return -ENOMEM; 750 751 memset(buf, 0, cc->iv_size); 752 *(__le64 *)buf = cpu_to_le64(dmreq->iv_sector * cc->sector_size); 753 754 sg_init_one(&src, page_address(ZERO_PAGE(0)), cc->iv_size); 755 sg_init_one(&dst, iv, cc->iv_size); 756 skcipher_request_set_crypt(req, &src, &dst, cc->iv_size, buf); 757 skcipher_request_set_callback(req, 0, crypto_req_done, &wait); 758 err = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 759 skcipher_request_free(req); 760 761 return err; 762 } 763 764 static void crypt_iv_elephant_dtr(struct crypt_config *cc) 765 { 766 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 767 768 crypto_free_skcipher(elephant->tfm); 769 elephant->tfm = NULL; 770 } 771 772 static int crypt_iv_elephant_ctr(struct crypt_config *cc, struct dm_target *ti, 773 const char *opts) 774 { 775 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 776 int r; 777 778 elephant->tfm = crypto_alloc_skcipher("ecb(aes)", 0, 779 CRYPTO_ALG_ALLOCATES_MEMORY); 780 if (IS_ERR(elephant->tfm)) { 781 r = PTR_ERR(elephant->tfm); 782 elephant->tfm = NULL; 783 return r; 784 } 785 786 r = crypt_iv_eboiv_ctr(cc, ti, NULL); 787 if (r) 788 crypt_iv_elephant_dtr(cc); 789 return r; 790 } 791 792 static void diffuser_disk_to_cpu(u32 *d, size_t n) 793 { 794 #ifndef __LITTLE_ENDIAN 795 int i; 796 797 for (i = 0; i < n; i++) 798 d[i] = le32_to_cpu((__le32)d[i]); 799 #endif 800 } 801 802 static void diffuser_cpu_to_disk(__le32 *d, size_t n) 803 { 804 #ifndef __LITTLE_ENDIAN 805 int i; 806 807 for (i = 0; i < n; i++) 808 d[i] = cpu_to_le32((u32)d[i]); 809 #endif 810 } 811 812 static void diffuser_a_decrypt(u32 *d, size_t n) 813 { 814 int i, i1, i2, i3; 815 816 for (i = 0; i < 5; i++) { 817 i1 = 0; 818 i2 = n - 2; 819 i3 = n - 5; 820 821 while (i1 < (n - 1)) { 822 d[i1] += d[i2] ^ (d[i3] << 9 | d[i3] >> 23); 823 i1++; i2++; i3++; 824 825 if (i3 >= n) 826 i3 -= n; 827 828 d[i1] += d[i2] ^ d[i3]; 829 i1++; i2++; i3++; 830 831 if (i2 >= n) 832 i2 -= n; 833 834 d[i1] += d[i2] ^ (d[i3] << 13 | d[i3] >> 19); 835 i1++; i2++; i3++; 836 837 d[i1] += d[i2] ^ d[i3]; 838 i1++; i2++; i3++; 839 } 840 } 841 } 842 843 static void diffuser_a_encrypt(u32 *d, size_t n) 844 { 845 int i, i1, i2, i3; 846 847 for (i = 0; i < 5; i++) { 848 i1 = n - 1; 849 i2 = n - 2 - 1; 850 i3 = n - 5 - 1; 851 852 while (i1 > 0) { 853 d[i1] -= d[i2] ^ d[i3]; 854 i1--; i2--; i3--; 855 856 d[i1] -= d[i2] ^ (d[i3] << 13 | d[i3] >> 19); 857 i1--; i2--; i3--; 858 859 if (i2 < 0) 860 i2 += n; 861 862 d[i1] -= d[i2] ^ d[i3]; 863 i1--; i2--; i3--; 864 865 if (i3 < 0) 866 i3 += n; 867 868 d[i1] -= d[i2] ^ (d[i3] << 9 | d[i3] >> 23); 869 i1--; i2--; i3--; 870 } 871 } 872 } 873 874 static void diffuser_b_decrypt(u32 *d, size_t n) 875 { 876 int i, i1, i2, i3; 877 878 for (i = 0; i < 3; i++) { 879 i1 = 0; 880 i2 = 2; 881 i3 = 5; 882 883 while (i1 < (n - 1)) { 884 d[i1] += d[i2] ^ d[i3]; 885 i1++; i2++; i3++; 886 887 d[i1] += d[i2] ^ (d[i3] << 10 | d[i3] >> 22); 888 i1++; i2++; i3++; 889 890 if (i2 >= n) 891 i2 -= n; 892 893 d[i1] += d[i2] ^ d[i3]; 894 i1++; i2++; i3++; 895 896 if (i3 >= n) 897 i3 -= n; 898 899 d[i1] += d[i2] ^ (d[i3] << 25 | d[i3] >> 7); 900 i1++; i2++; i3++; 901 } 902 } 903 } 904 905 static void diffuser_b_encrypt(u32 *d, size_t n) 906 { 907 int i, i1, i2, i3; 908 909 for (i = 0; i < 3; i++) { 910 i1 = n - 1; 911 i2 = 2 - 1; 912 i3 = 5 - 1; 913 914 while (i1 > 0) { 915 d[i1] -= d[i2] ^ (d[i3] << 25 | d[i3] >> 7); 916 i1--; i2--; i3--; 917 918 if (i3 < 0) 919 i3 += n; 920 921 d[i1] -= d[i2] ^ d[i3]; 922 i1--; i2--; i3--; 923 924 if (i2 < 0) 925 i2 += n; 926 927 d[i1] -= d[i2] ^ (d[i3] << 10 | d[i3] >> 22); 928 i1--; i2--; i3--; 929 930 d[i1] -= d[i2] ^ d[i3]; 931 i1--; i2--; i3--; 932 } 933 } 934 } 935 936 static int crypt_iv_elephant(struct crypt_config *cc, struct dm_crypt_request *dmreq) 937 { 938 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 939 u8 *es, *ks, *data, *data2, *data_offset; 940 struct skcipher_request *req; 941 struct scatterlist *sg, *sg2, src, dst; 942 DECLARE_CRYPTO_WAIT(wait); 943 int i, r; 944 945 req = skcipher_request_alloc(elephant->tfm, GFP_NOIO); 946 es = kzalloc(16, GFP_NOIO); /* Key for AES */ 947 ks = kzalloc(32, GFP_NOIO); /* Elephant sector key */ 948 949 if (!req || !es || !ks) { 950 r = -ENOMEM; 951 goto out; 952 } 953 954 *(__le64 *)es = cpu_to_le64(dmreq->iv_sector * cc->sector_size); 955 956 /* E(Ks, e(s)) */ 957 sg_init_one(&src, es, 16); 958 sg_init_one(&dst, ks, 16); 959 skcipher_request_set_crypt(req, &src, &dst, 16, NULL); 960 skcipher_request_set_callback(req, 0, crypto_req_done, &wait); 961 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 962 if (r) 963 goto out; 964 965 /* E(Ks, e'(s)) */ 966 es[15] = 0x80; 967 sg_init_one(&dst, &ks[16], 16); 968 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 969 if (r) 970 goto out; 971 972 sg = crypt_get_sg_data(cc, dmreq->sg_out); 973 data = kmap_atomic(sg_page(sg)); 974 data_offset = data + sg->offset; 975 976 /* Cannot modify original bio, copy to sg_out and apply Elephant to it */ 977 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 978 sg2 = crypt_get_sg_data(cc, dmreq->sg_in); 979 data2 = kmap_atomic(sg_page(sg2)); 980 memcpy(data_offset, data2 + sg2->offset, cc->sector_size); 981 kunmap_atomic(data2); 982 } 983 984 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 985 diffuser_disk_to_cpu((u32*)data_offset, cc->sector_size / sizeof(u32)); 986 diffuser_b_decrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 987 diffuser_a_decrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 988 diffuser_cpu_to_disk((__le32*)data_offset, cc->sector_size / sizeof(u32)); 989 } 990 991 for (i = 0; i < (cc->sector_size / 32); i++) 992 crypto_xor(data_offset + i * 32, ks, 32); 993 994 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 995 diffuser_disk_to_cpu((u32*)data_offset, cc->sector_size / sizeof(u32)); 996 diffuser_a_encrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 997 diffuser_b_encrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 998 diffuser_cpu_to_disk((__le32*)data_offset, cc->sector_size / sizeof(u32)); 999 } 1000 1001 kunmap_atomic(data); 1002 out: 1003 kfree_sensitive(ks); 1004 kfree_sensitive(es); 1005 skcipher_request_free(req); 1006 return r; 1007 } 1008 1009 static int crypt_iv_elephant_gen(struct crypt_config *cc, u8 *iv, 1010 struct dm_crypt_request *dmreq) 1011 { 1012 int r; 1013 1014 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 1015 r = crypt_iv_elephant(cc, dmreq); 1016 if (r) 1017 return r; 1018 } 1019 1020 return crypt_iv_eboiv_gen(cc, iv, dmreq); 1021 } 1022 1023 static int crypt_iv_elephant_post(struct crypt_config *cc, u8 *iv, 1024 struct dm_crypt_request *dmreq) 1025 { 1026 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 1027 return crypt_iv_elephant(cc, dmreq); 1028 1029 return 0; 1030 } 1031 1032 static int crypt_iv_elephant_init(struct crypt_config *cc) 1033 { 1034 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 1035 int key_offset = cc->key_size - cc->key_extra_size; 1036 1037 return crypto_skcipher_setkey(elephant->tfm, &cc->key[key_offset], cc->key_extra_size); 1038 } 1039 1040 static int crypt_iv_elephant_wipe(struct crypt_config *cc) 1041 { 1042 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 1043 u8 key[ELEPHANT_MAX_KEY_SIZE]; 1044 1045 memset(key, 0, cc->key_extra_size); 1046 return crypto_skcipher_setkey(elephant->tfm, key, cc->key_extra_size); 1047 } 1048 1049 static const struct crypt_iv_operations crypt_iv_plain_ops = { 1050 .generator = crypt_iv_plain_gen 1051 }; 1052 1053 static const struct crypt_iv_operations crypt_iv_plain64_ops = { 1054 .generator = crypt_iv_plain64_gen 1055 }; 1056 1057 static const struct crypt_iv_operations crypt_iv_plain64be_ops = { 1058 .generator = crypt_iv_plain64be_gen 1059 }; 1060 1061 static const struct crypt_iv_operations crypt_iv_essiv_ops = { 1062 .generator = crypt_iv_essiv_gen 1063 }; 1064 1065 static const struct crypt_iv_operations crypt_iv_benbi_ops = { 1066 .ctr = crypt_iv_benbi_ctr, 1067 .dtr = crypt_iv_benbi_dtr, 1068 .generator = crypt_iv_benbi_gen 1069 }; 1070 1071 static const struct crypt_iv_operations crypt_iv_null_ops = { 1072 .generator = crypt_iv_null_gen 1073 }; 1074 1075 static const struct crypt_iv_operations crypt_iv_lmk_ops = { 1076 .ctr = crypt_iv_lmk_ctr, 1077 .dtr = crypt_iv_lmk_dtr, 1078 .init = crypt_iv_lmk_init, 1079 .wipe = crypt_iv_lmk_wipe, 1080 .generator = crypt_iv_lmk_gen, 1081 .post = crypt_iv_lmk_post 1082 }; 1083 1084 static const struct crypt_iv_operations crypt_iv_tcw_ops = { 1085 .ctr = crypt_iv_tcw_ctr, 1086 .dtr = crypt_iv_tcw_dtr, 1087 .init = crypt_iv_tcw_init, 1088 .wipe = crypt_iv_tcw_wipe, 1089 .generator = crypt_iv_tcw_gen, 1090 .post = crypt_iv_tcw_post 1091 }; 1092 1093 static const struct crypt_iv_operations crypt_iv_random_ops = { 1094 .generator = crypt_iv_random_gen 1095 }; 1096 1097 static const struct crypt_iv_operations crypt_iv_eboiv_ops = { 1098 .ctr = crypt_iv_eboiv_ctr, 1099 .generator = crypt_iv_eboiv_gen 1100 }; 1101 1102 static const struct crypt_iv_operations crypt_iv_elephant_ops = { 1103 .ctr = crypt_iv_elephant_ctr, 1104 .dtr = crypt_iv_elephant_dtr, 1105 .init = crypt_iv_elephant_init, 1106 .wipe = crypt_iv_elephant_wipe, 1107 .generator = crypt_iv_elephant_gen, 1108 .post = crypt_iv_elephant_post 1109 }; 1110 1111 /* 1112 * Integrity extensions 1113 */ 1114 static bool crypt_integrity_aead(struct crypt_config *cc) 1115 { 1116 return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 1117 } 1118 1119 static bool crypt_integrity_hmac(struct crypt_config *cc) 1120 { 1121 return crypt_integrity_aead(cc) && cc->key_mac_size; 1122 } 1123 1124 /* Get sg containing data */ 1125 static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 1126 struct scatterlist *sg) 1127 { 1128 if (unlikely(crypt_integrity_aead(cc))) 1129 return &sg[2]; 1130 1131 return sg; 1132 } 1133 1134 static int dm_crypt_integrity_io_alloc(struct dm_crypt_io *io, struct bio *bio) 1135 { 1136 struct bio_integrity_payload *bip; 1137 unsigned int tag_len; 1138 int ret; 1139 1140 if (!bio_sectors(bio) || !io->cc->on_disk_tag_size) 1141 return 0; 1142 1143 bip = bio_integrity_alloc(bio, GFP_NOIO, 1); 1144 if (IS_ERR(bip)) 1145 return PTR_ERR(bip); 1146 1147 tag_len = io->cc->on_disk_tag_size * (bio_sectors(bio) >> io->cc->sector_shift); 1148 1149 bip->bip_iter.bi_size = tag_len; 1150 bip->bip_iter.bi_sector = io->cc->start + io->sector; 1151 1152 ret = bio_integrity_add_page(bio, virt_to_page(io->integrity_metadata), 1153 tag_len, offset_in_page(io->integrity_metadata)); 1154 if (unlikely(ret != tag_len)) 1155 return -ENOMEM; 1156 1157 return 0; 1158 } 1159 1160 static int crypt_integrity_ctr(struct crypt_config *cc, struct dm_target *ti) 1161 { 1162 #ifdef CONFIG_BLK_DEV_INTEGRITY 1163 struct blk_integrity *bi = blk_get_integrity(cc->dev->bdev->bd_disk); 1164 struct mapped_device *md = dm_table_get_md(ti->table); 1165 1166 /* From now we require underlying device with our integrity profile */ 1167 if (!bi || strcasecmp(bi->profile->name, "DM-DIF-EXT-TAG")) { 1168 ti->error = "Integrity profile not supported."; 1169 return -EINVAL; 1170 } 1171 1172 if (bi->tag_size != cc->on_disk_tag_size || 1173 bi->tuple_size != cc->on_disk_tag_size) { 1174 ti->error = "Integrity profile tag size mismatch."; 1175 return -EINVAL; 1176 } 1177 if (1 << bi->interval_exp != cc->sector_size) { 1178 ti->error = "Integrity profile sector size mismatch."; 1179 return -EINVAL; 1180 } 1181 1182 if (crypt_integrity_aead(cc)) { 1183 cc->integrity_tag_size = cc->on_disk_tag_size - cc->integrity_iv_size; 1184 DMDEBUG("%s: Integrity AEAD, tag size %u, IV size %u.", dm_device_name(md), 1185 cc->integrity_tag_size, cc->integrity_iv_size); 1186 1187 if (crypto_aead_setauthsize(any_tfm_aead(cc), cc->integrity_tag_size)) { 1188 ti->error = "Integrity AEAD auth tag size is not supported."; 1189 return -EINVAL; 1190 } 1191 } else if (cc->integrity_iv_size) 1192 DMDEBUG("%s: Additional per-sector space %u bytes for IV.", dm_device_name(md), 1193 cc->integrity_iv_size); 1194 1195 if ((cc->integrity_tag_size + cc->integrity_iv_size) != bi->tag_size) { 1196 ti->error = "Not enough space for integrity tag in the profile."; 1197 return -EINVAL; 1198 } 1199 1200 return 0; 1201 #else 1202 ti->error = "Integrity profile not supported."; 1203 return -EINVAL; 1204 #endif 1205 } 1206 1207 static void crypt_convert_init(struct crypt_config *cc, 1208 struct convert_context *ctx, 1209 struct bio *bio_out, struct bio *bio_in, 1210 sector_t sector) 1211 { 1212 ctx->bio_in = bio_in; 1213 ctx->bio_out = bio_out; 1214 if (bio_in) 1215 ctx->iter_in = bio_in->bi_iter; 1216 if (bio_out) 1217 ctx->iter_out = bio_out->bi_iter; 1218 ctx->cc_sector = sector + cc->iv_offset; 1219 init_completion(&ctx->restart); 1220 } 1221 1222 static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc, 1223 void *req) 1224 { 1225 return (struct dm_crypt_request *)((char *)req + cc->dmreq_start); 1226 } 1227 1228 static void *req_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq) 1229 { 1230 return (void *)((char *)dmreq - cc->dmreq_start); 1231 } 1232 1233 static u8 *iv_of_dmreq(struct crypt_config *cc, 1234 struct dm_crypt_request *dmreq) 1235 { 1236 if (crypt_integrity_aead(cc)) 1237 return (u8 *)ALIGN((unsigned long)(dmreq + 1), 1238 crypto_aead_alignmask(any_tfm_aead(cc)) + 1); 1239 else 1240 return (u8 *)ALIGN((unsigned long)(dmreq + 1), 1241 crypto_skcipher_alignmask(any_tfm(cc)) + 1); 1242 } 1243 1244 static u8 *org_iv_of_dmreq(struct crypt_config *cc, 1245 struct dm_crypt_request *dmreq) 1246 { 1247 return iv_of_dmreq(cc, dmreq) + cc->iv_size; 1248 } 1249 1250 static __le64 *org_sector_of_dmreq(struct crypt_config *cc, 1251 struct dm_crypt_request *dmreq) 1252 { 1253 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + cc->iv_size; 1254 return (__le64 *) ptr; 1255 } 1256 1257 static unsigned int *org_tag_of_dmreq(struct crypt_config *cc, 1258 struct dm_crypt_request *dmreq) 1259 { 1260 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + 1261 cc->iv_size + sizeof(uint64_t); 1262 return (unsigned int*)ptr; 1263 } 1264 1265 static void *tag_from_dmreq(struct crypt_config *cc, 1266 struct dm_crypt_request *dmreq) 1267 { 1268 struct convert_context *ctx = dmreq->ctx; 1269 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 1270 1271 return &io->integrity_metadata[*org_tag_of_dmreq(cc, dmreq) * 1272 cc->on_disk_tag_size]; 1273 } 1274 1275 static void *iv_tag_from_dmreq(struct crypt_config *cc, 1276 struct dm_crypt_request *dmreq) 1277 { 1278 return tag_from_dmreq(cc, dmreq) + cc->integrity_tag_size; 1279 } 1280 1281 static int crypt_convert_block_aead(struct crypt_config *cc, 1282 struct convert_context *ctx, 1283 struct aead_request *req, 1284 unsigned int tag_offset) 1285 { 1286 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1287 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1288 struct dm_crypt_request *dmreq; 1289 u8 *iv, *org_iv, *tag_iv, *tag; 1290 __le64 *sector; 1291 int r = 0; 1292 1293 BUG_ON(cc->integrity_iv_size && cc->integrity_iv_size != cc->iv_size); 1294 1295 /* Reject unexpected unaligned bio. */ 1296 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1297 return -EIO; 1298 1299 dmreq = dmreq_of_req(cc, req); 1300 dmreq->iv_sector = ctx->cc_sector; 1301 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1302 dmreq->iv_sector >>= cc->sector_shift; 1303 dmreq->ctx = ctx; 1304 1305 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1306 1307 sector = org_sector_of_dmreq(cc, dmreq); 1308 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1309 1310 iv = iv_of_dmreq(cc, dmreq); 1311 org_iv = org_iv_of_dmreq(cc, dmreq); 1312 tag = tag_from_dmreq(cc, dmreq); 1313 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1314 1315 /* AEAD request: 1316 * |----- AAD -------|------ DATA -------|-- AUTH TAG --| 1317 * | (authenticated) | (auth+encryption) | | 1318 * | sector_LE | IV | sector in/out | tag in/out | 1319 */ 1320 sg_init_table(dmreq->sg_in, 4); 1321 sg_set_buf(&dmreq->sg_in[0], sector, sizeof(uint64_t)); 1322 sg_set_buf(&dmreq->sg_in[1], org_iv, cc->iv_size); 1323 sg_set_page(&dmreq->sg_in[2], bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1324 sg_set_buf(&dmreq->sg_in[3], tag, cc->integrity_tag_size); 1325 1326 sg_init_table(dmreq->sg_out, 4); 1327 sg_set_buf(&dmreq->sg_out[0], sector, sizeof(uint64_t)); 1328 sg_set_buf(&dmreq->sg_out[1], org_iv, cc->iv_size); 1329 sg_set_page(&dmreq->sg_out[2], bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1330 sg_set_buf(&dmreq->sg_out[3], tag, cc->integrity_tag_size); 1331 1332 if (cc->iv_gen_ops) { 1333 /* For READs use IV stored in integrity metadata */ 1334 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1335 memcpy(org_iv, tag_iv, cc->iv_size); 1336 } else { 1337 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1338 if (r < 0) 1339 return r; 1340 /* Store generated IV in integrity metadata */ 1341 if (cc->integrity_iv_size) 1342 memcpy(tag_iv, org_iv, cc->iv_size); 1343 } 1344 /* Working copy of IV, to be modified in crypto API */ 1345 memcpy(iv, org_iv, cc->iv_size); 1346 } 1347 1348 aead_request_set_ad(req, sizeof(uint64_t) + cc->iv_size); 1349 if (bio_data_dir(ctx->bio_in) == WRITE) { 1350 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out, 1351 cc->sector_size, iv); 1352 r = crypto_aead_encrypt(req); 1353 if (cc->integrity_tag_size + cc->integrity_iv_size != cc->on_disk_tag_size) 1354 memset(tag + cc->integrity_tag_size + cc->integrity_iv_size, 0, 1355 cc->on_disk_tag_size - (cc->integrity_tag_size + cc->integrity_iv_size)); 1356 } else { 1357 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out, 1358 cc->sector_size + cc->integrity_tag_size, iv); 1359 r = crypto_aead_decrypt(req); 1360 } 1361 1362 if (r == -EBADMSG) { 1363 char b[BDEVNAME_SIZE]; 1364 DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu", bio_devname(ctx->bio_in, b), 1365 (unsigned long long)le64_to_cpu(*sector)); 1366 } 1367 1368 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1369 r = cc->iv_gen_ops->post(cc, org_iv, dmreq); 1370 1371 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1372 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1373 1374 return r; 1375 } 1376 1377 static int crypt_convert_block_skcipher(struct crypt_config *cc, 1378 struct convert_context *ctx, 1379 struct skcipher_request *req, 1380 unsigned int tag_offset) 1381 { 1382 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1383 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1384 struct scatterlist *sg_in, *sg_out; 1385 struct dm_crypt_request *dmreq; 1386 u8 *iv, *org_iv, *tag_iv; 1387 __le64 *sector; 1388 int r = 0; 1389 1390 /* Reject unexpected unaligned bio. */ 1391 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1392 return -EIO; 1393 1394 dmreq = dmreq_of_req(cc, req); 1395 dmreq->iv_sector = ctx->cc_sector; 1396 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1397 dmreq->iv_sector >>= cc->sector_shift; 1398 dmreq->ctx = ctx; 1399 1400 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1401 1402 iv = iv_of_dmreq(cc, dmreq); 1403 org_iv = org_iv_of_dmreq(cc, dmreq); 1404 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1405 1406 sector = org_sector_of_dmreq(cc, dmreq); 1407 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1408 1409 /* For skcipher we use only the first sg item */ 1410 sg_in = &dmreq->sg_in[0]; 1411 sg_out = &dmreq->sg_out[0]; 1412 1413 sg_init_table(sg_in, 1); 1414 sg_set_page(sg_in, bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1415 1416 sg_init_table(sg_out, 1); 1417 sg_set_page(sg_out, bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1418 1419 if (cc->iv_gen_ops) { 1420 /* For READs use IV stored in integrity metadata */ 1421 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1422 memcpy(org_iv, tag_iv, cc->integrity_iv_size); 1423 } else { 1424 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1425 if (r < 0) 1426 return r; 1427 /* Data can be already preprocessed in generator */ 1428 if (test_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags)) 1429 sg_in = sg_out; 1430 /* Store generated IV in integrity metadata */ 1431 if (cc->integrity_iv_size) 1432 memcpy(tag_iv, org_iv, cc->integrity_iv_size); 1433 } 1434 /* Working copy of IV, to be modified in crypto API */ 1435 memcpy(iv, org_iv, cc->iv_size); 1436 } 1437 1438 skcipher_request_set_crypt(req, sg_in, sg_out, cc->sector_size, iv); 1439 1440 if (bio_data_dir(ctx->bio_in) == WRITE) 1441 r = crypto_skcipher_encrypt(req); 1442 else 1443 r = crypto_skcipher_decrypt(req); 1444 1445 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1446 r = cc->iv_gen_ops->post(cc, org_iv, dmreq); 1447 1448 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1449 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1450 1451 return r; 1452 } 1453 1454 static void kcryptd_async_done(struct crypto_async_request *async_req, 1455 int error); 1456 1457 static void crypt_alloc_req_skcipher(struct crypt_config *cc, 1458 struct convert_context *ctx) 1459 { 1460 unsigned key_index = ctx->cc_sector & (cc->tfms_count - 1); 1461 1462 if (!ctx->r.req) 1463 ctx->r.req = mempool_alloc(&cc->req_pool, GFP_NOIO); 1464 1465 skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]); 1466 1467 /* 1468 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1469 * requests if driver request queue is full. 1470 */ 1471 skcipher_request_set_callback(ctx->r.req, 1472 CRYPTO_TFM_REQ_MAY_BACKLOG, 1473 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req)); 1474 } 1475 1476 static void crypt_alloc_req_aead(struct crypt_config *cc, 1477 struct convert_context *ctx) 1478 { 1479 if (!ctx->r.req_aead) 1480 ctx->r.req_aead = mempool_alloc(&cc->req_pool, GFP_NOIO); 1481 1482 aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]); 1483 1484 /* 1485 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1486 * requests if driver request queue is full. 1487 */ 1488 aead_request_set_callback(ctx->r.req_aead, 1489 CRYPTO_TFM_REQ_MAY_BACKLOG, 1490 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead)); 1491 } 1492 1493 static void crypt_alloc_req(struct crypt_config *cc, 1494 struct convert_context *ctx) 1495 { 1496 if (crypt_integrity_aead(cc)) 1497 crypt_alloc_req_aead(cc, ctx); 1498 else 1499 crypt_alloc_req_skcipher(cc, ctx); 1500 } 1501 1502 static void crypt_free_req_skcipher(struct crypt_config *cc, 1503 struct skcipher_request *req, struct bio *base_bio) 1504 { 1505 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1506 1507 if ((struct skcipher_request *)(io + 1) != req) 1508 mempool_free(req, &cc->req_pool); 1509 } 1510 1511 static void crypt_free_req_aead(struct crypt_config *cc, 1512 struct aead_request *req, struct bio *base_bio) 1513 { 1514 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1515 1516 if ((struct aead_request *)(io + 1) != req) 1517 mempool_free(req, &cc->req_pool); 1518 } 1519 1520 static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio) 1521 { 1522 if (crypt_integrity_aead(cc)) 1523 crypt_free_req_aead(cc, req, base_bio); 1524 else 1525 crypt_free_req_skcipher(cc, req, base_bio); 1526 } 1527 1528 /* 1529 * Encrypt / decrypt data from one bio to another one (can be the same one) 1530 */ 1531 static blk_status_t crypt_convert(struct crypt_config *cc, 1532 struct convert_context *ctx, bool atomic) 1533 { 1534 unsigned int tag_offset = 0; 1535 unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT; 1536 int r; 1537 1538 atomic_set(&ctx->cc_pending, 1); 1539 1540 while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) { 1541 1542 crypt_alloc_req(cc, ctx); 1543 atomic_inc(&ctx->cc_pending); 1544 1545 if (crypt_integrity_aead(cc)) 1546 r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, tag_offset); 1547 else 1548 r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, tag_offset); 1549 1550 switch (r) { 1551 /* 1552 * The request was queued by a crypto driver 1553 * but the driver request queue is full, let's wait. 1554 */ 1555 case -EBUSY: 1556 wait_for_completion(&ctx->restart); 1557 reinit_completion(&ctx->restart); 1558 fallthrough; 1559 /* 1560 * The request is queued and processed asynchronously, 1561 * completion function kcryptd_async_done() will be called. 1562 */ 1563 case -EINPROGRESS: 1564 ctx->r.req = NULL; 1565 ctx->cc_sector += sector_step; 1566 tag_offset++; 1567 continue; 1568 /* 1569 * The request was already processed (synchronously). 1570 */ 1571 case 0: 1572 atomic_dec(&ctx->cc_pending); 1573 ctx->cc_sector += sector_step; 1574 tag_offset++; 1575 if (!atomic) 1576 cond_resched(); 1577 continue; 1578 /* 1579 * There was a data integrity error. 1580 */ 1581 case -EBADMSG: 1582 atomic_dec(&ctx->cc_pending); 1583 return BLK_STS_PROTECTION; 1584 /* 1585 * There was an error while processing the request. 1586 */ 1587 default: 1588 atomic_dec(&ctx->cc_pending); 1589 return BLK_STS_IOERR; 1590 } 1591 } 1592 1593 return 0; 1594 } 1595 1596 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone); 1597 1598 /* 1599 * Generate a new unfragmented bio with the given size 1600 * This should never violate the device limitations (but only because 1601 * max_segment_size is being constrained to PAGE_SIZE). 1602 * 1603 * This function may be called concurrently. If we allocate from the mempool 1604 * concurrently, there is a possibility of deadlock. For example, if we have 1605 * mempool of 256 pages, two processes, each wanting 256, pages allocate from 1606 * the mempool concurrently, it may deadlock in a situation where both processes 1607 * have allocated 128 pages and the mempool is exhausted. 1608 * 1609 * In order to avoid this scenario we allocate the pages under a mutex. 1610 * 1611 * In order to not degrade performance with excessive locking, we try 1612 * non-blocking allocations without a mutex first but on failure we fallback 1613 * to blocking allocations with a mutex. 1614 */ 1615 static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size) 1616 { 1617 struct crypt_config *cc = io->cc; 1618 struct bio *clone; 1619 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; 1620 gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM; 1621 unsigned i, len, remaining_size; 1622 struct page *page; 1623 1624 retry: 1625 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1626 mutex_lock(&cc->bio_alloc_lock); 1627 1628 clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, &cc->bs); 1629 if (!clone) 1630 goto out; 1631 1632 clone_init(io, clone); 1633 1634 remaining_size = size; 1635 1636 for (i = 0; i < nr_iovecs; i++) { 1637 page = mempool_alloc(&cc->page_pool, gfp_mask); 1638 if (!page) { 1639 crypt_free_buffer_pages(cc, clone); 1640 bio_put(clone); 1641 gfp_mask |= __GFP_DIRECT_RECLAIM; 1642 goto retry; 1643 } 1644 1645 len = (remaining_size > PAGE_SIZE) ? PAGE_SIZE : remaining_size; 1646 1647 bio_add_page(clone, page, len, 0); 1648 1649 remaining_size -= len; 1650 } 1651 1652 /* Allocate space for integrity tags */ 1653 if (dm_crypt_integrity_io_alloc(io, clone)) { 1654 crypt_free_buffer_pages(cc, clone); 1655 bio_put(clone); 1656 clone = NULL; 1657 } 1658 out: 1659 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1660 mutex_unlock(&cc->bio_alloc_lock); 1661 1662 return clone; 1663 } 1664 1665 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) 1666 { 1667 struct bio_vec *bv; 1668 struct bvec_iter_all iter_all; 1669 1670 bio_for_each_segment_all(bv, clone, iter_all) { 1671 BUG_ON(!bv->bv_page); 1672 mempool_free(bv->bv_page, &cc->page_pool); 1673 } 1674 } 1675 1676 static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc, 1677 struct bio *bio, sector_t sector) 1678 { 1679 io->cc = cc; 1680 io->base_bio = bio; 1681 io->sector = sector; 1682 io->error = 0; 1683 io->ctx.r.req = NULL; 1684 io->integrity_metadata = NULL; 1685 io->integrity_metadata_from_pool = false; 1686 atomic_set(&io->io_pending, 0); 1687 } 1688 1689 static void crypt_inc_pending(struct dm_crypt_io *io) 1690 { 1691 atomic_inc(&io->io_pending); 1692 } 1693 1694 /* 1695 * One of the bios was finished. Check for completion of 1696 * the whole request and correctly clean up the buffer. 1697 */ 1698 static void crypt_dec_pending(struct dm_crypt_io *io) 1699 { 1700 struct crypt_config *cc = io->cc; 1701 struct bio *base_bio = io->base_bio; 1702 blk_status_t error = io->error; 1703 1704 if (!atomic_dec_and_test(&io->io_pending)) 1705 return; 1706 1707 if (io->ctx.r.req) 1708 crypt_free_req(cc, io->ctx.r.req, base_bio); 1709 1710 if (unlikely(io->integrity_metadata_from_pool)) 1711 mempool_free(io->integrity_metadata, &io->cc->tag_pool); 1712 else 1713 kfree(io->integrity_metadata); 1714 1715 base_bio->bi_status = error; 1716 bio_endio(base_bio); 1717 } 1718 1719 /* 1720 * kcryptd/kcryptd_io: 1721 * 1722 * Needed because it would be very unwise to do decryption in an 1723 * interrupt context. 1724 * 1725 * kcryptd performs the actual encryption or decryption. 1726 * 1727 * kcryptd_io performs the IO submission. 1728 * 1729 * They must be separated as otherwise the final stages could be 1730 * starved by new requests which can block in the first stages due 1731 * to memory allocation. 1732 * 1733 * The work is done per CPU global for all dm-crypt instances. 1734 * They should not depend on each other and do not block. 1735 */ 1736 static void crypt_endio(struct bio *clone) 1737 { 1738 struct dm_crypt_io *io = clone->bi_private; 1739 struct crypt_config *cc = io->cc; 1740 unsigned rw = bio_data_dir(clone); 1741 blk_status_t error; 1742 1743 /* 1744 * free the processed pages 1745 */ 1746 if (rw == WRITE) 1747 crypt_free_buffer_pages(cc, clone); 1748 1749 error = clone->bi_status; 1750 bio_put(clone); 1751 1752 if (rw == READ && !error) { 1753 kcryptd_queue_crypt(io); 1754 return; 1755 } 1756 1757 if (unlikely(error)) 1758 io->error = error; 1759 1760 crypt_dec_pending(io); 1761 } 1762 1763 static void clone_init(struct dm_crypt_io *io, struct bio *clone) 1764 { 1765 struct crypt_config *cc = io->cc; 1766 1767 clone->bi_private = io; 1768 clone->bi_end_io = crypt_endio; 1769 bio_set_dev(clone, cc->dev->bdev); 1770 clone->bi_opf = io->base_bio->bi_opf; 1771 } 1772 1773 static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp) 1774 { 1775 struct crypt_config *cc = io->cc; 1776 struct bio *clone; 1777 1778 /* 1779 * We need the original biovec array in order to decrypt 1780 * the whole bio data *afterwards* -- thanks to immutable 1781 * biovecs we don't need to worry about the block layer 1782 * modifying the biovec array; so leverage bio_clone_fast(). 1783 */ 1784 clone = bio_clone_fast(io->base_bio, gfp, &cc->bs); 1785 if (!clone) 1786 return 1; 1787 1788 crypt_inc_pending(io); 1789 1790 clone_init(io, clone); 1791 clone->bi_iter.bi_sector = cc->start + io->sector; 1792 1793 if (dm_crypt_integrity_io_alloc(io, clone)) { 1794 crypt_dec_pending(io); 1795 bio_put(clone); 1796 return 1; 1797 } 1798 1799 submit_bio_noacct(clone); 1800 return 0; 1801 } 1802 1803 static void kcryptd_io_read_work(struct work_struct *work) 1804 { 1805 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 1806 1807 crypt_inc_pending(io); 1808 if (kcryptd_io_read(io, GFP_NOIO)) 1809 io->error = BLK_STS_RESOURCE; 1810 crypt_dec_pending(io); 1811 } 1812 1813 static void kcryptd_queue_read(struct dm_crypt_io *io) 1814 { 1815 struct crypt_config *cc = io->cc; 1816 1817 INIT_WORK(&io->work, kcryptd_io_read_work); 1818 queue_work(cc->io_queue, &io->work); 1819 } 1820 1821 static void kcryptd_io_write(struct dm_crypt_io *io) 1822 { 1823 struct bio *clone = io->ctx.bio_out; 1824 1825 submit_bio_noacct(clone); 1826 } 1827 1828 #define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node) 1829 1830 static int dmcrypt_write(void *data) 1831 { 1832 struct crypt_config *cc = data; 1833 struct dm_crypt_io *io; 1834 1835 while (1) { 1836 struct rb_root write_tree; 1837 struct blk_plug plug; 1838 1839 spin_lock_irq(&cc->write_thread_lock); 1840 continue_locked: 1841 1842 if (!RB_EMPTY_ROOT(&cc->write_tree)) 1843 goto pop_from_list; 1844 1845 set_current_state(TASK_INTERRUPTIBLE); 1846 1847 spin_unlock_irq(&cc->write_thread_lock); 1848 1849 if (unlikely(kthread_should_stop())) { 1850 set_current_state(TASK_RUNNING); 1851 break; 1852 } 1853 1854 schedule(); 1855 1856 set_current_state(TASK_RUNNING); 1857 spin_lock_irq(&cc->write_thread_lock); 1858 goto continue_locked; 1859 1860 pop_from_list: 1861 write_tree = cc->write_tree; 1862 cc->write_tree = RB_ROOT; 1863 spin_unlock_irq(&cc->write_thread_lock); 1864 1865 BUG_ON(rb_parent(write_tree.rb_node)); 1866 1867 /* 1868 * Note: we cannot walk the tree here with rb_next because 1869 * the structures may be freed when kcryptd_io_write is called. 1870 */ 1871 blk_start_plug(&plug); 1872 do { 1873 io = crypt_io_from_node(rb_first(&write_tree)); 1874 rb_erase(&io->rb_node, &write_tree); 1875 kcryptd_io_write(io); 1876 } while (!RB_EMPTY_ROOT(&write_tree)); 1877 blk_finish_plug(&plug); 1878 } 1879 return 0; 1880 } 1881 1882 static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async) 1883 { 1884 struct bio *clone = io->ctx.bio_out; 1885 struct crypt_config *cc = io->cc; 1886 unsigned long flags; 1887 sector_t sector; 1888 struct rb_node **rbp, *parent; 1889 1890 if (unlikely(io->error)) { 1891 crypt_free_buffer_pages(cc, clone); 1892 bio_put(clone); 1893 crypt_dec_pending(io); 1894 return; 1895 } 1896 1897 /* crypt_convert should have filled the clone bio */ 1898 BUG_ON(io->ctx.iter_out.bi_size); 1899 1900 clone->bi_iter.bi_sector = cc->start + io->sector; 1901 1902 if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) || 1903 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) { 1904 submit_bio_noacct(clone); 1905 return; 1906 } 1907 1908 spin_lock_irqsave(&cc->write_thread_lock, flags); 1909 if (RB_EMPTY_ROOT(&cc->write_tree)) 1910 wake_up_process(cc->write_thread); 1911 rbp = &cc->write_tree.rb_node; 1912 parent = NULL; 1913 sector = io->sector; 1914 while (*rbp) { 1915 parent = *rbp; 1916 if (sector < crypt_io_from_node(parent)->sector) 1917 rbp = &(*rbp)->rb_left; 1918 else 1919 rbp = &(*rbp)->rb_right; 1920 } 1921 rb_link_node(&io->rb_node, parent, rbp); 1922 rb_insert_color(&io->rb_node, &cc->write_tree); 1923 spin_unlock_irqrestore(&cc->write_thread_lock, flags); 1924 } 1925 1926 static bool kcryptd_crypt_write_inline(struct crypt_config *cc, 1927 struct convert_context *ctx) 1928 1929 { 1930 if (!test_bit(DM_CRYPT_WRITE_INLINE, &cc->flags)) 1931 return false; 1932 1933 /* 1934 * Note: zone append writes (REQ_OP_ZONE_APPEND) do not have ordering 1935 * constraints so they do not need to be issued inline by 1936 * kcryptd_crypt_write_convert(). 1937 */ 1938 switch (bio_op(ctx->bio_in)) { 1939 case REQ_OP_WRITE: 1940 case REQ_OP_WRITE_SAME: 1941 case REQ_OP_WRITE_ZEROES: 1942 return true; 1943 default: 1944 return false; 1945 } 1946 } 1947 1948 static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) 1949 { 1950 struct crypt_config *cc = io->cc; 1951 struct convert_context *ctx = &io->ctx; 1952 struct bio *clone; 1953 int crypt_finished; 1954 sector_t sector = io->sector; 1955 blk_status_t r; 1956 1957 /* 1958 * Prevent io from disappearing until this function completes. 1959 */ 1960 crypt_inc_pending(io); 1961 crypt_convert_init(cc, ctx, NULL, io->base_bio, sector); 1962 1963 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size); 1964 if (unlikely(!clone)) { 1965 io->error = BLK_STS_IOERR; 1966 goto dec; 1967 } 1968 1969 io->ctx.bio_out = clone; 1970 io->ctx.iter_out = clone->bi_iter; 1971 1972 sector += bio_sectors(clone); 1973 1974 crypt_inc_pending(io); 1975 r = crypt_convert(cc, ctx, 1976 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)); 1977 if (r) 1978 io->error = r; 1979 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 1980 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 1981 /* Wait for completion signaled by kcryptd_async_done() */ 1982 wait_for_completion(&ctx->restart); 1983 crypt_finished = 1; 1984 } 1985 1986 /* Encryption was already finished, submit io now */ 1987 if (crypt_finished) { 1988 kcryptd_crypt_write_io_submit(io, 0); 1989 io->sector = sector; 1990 } 1991 1992 dec: 1993 crypt_dec_pending(io); 1994 } 1995 1996 static void kcryptd_crypt_read_done(struct dm_crypt_io *io) 1997 { 1998 crypt_dec_pending(io); 1999 } 2000 2001 static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) 2002 { 2003 struct crypt_config *cc = io->cc; 2004 blk_status_t r; 2005 2006 crypt_inc_pending(io); 2007 2008 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, 2009 io->sector); 2010 2011 r = crypt_convert(cc, &io->ctx, 2012 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)); 2013 if (r) 2014 io->error = r; 2015 2016 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2017 kcryptd_crypt_read_done(io); 2018 2019 crypt_dec_pending(io); 2020 } 2021 2022 static void kcryptd_async_done(struct crypto_async_request *async_req, 2023 int error) 2024 { 2025 struct dm_crypt_request *dmreq = async_req->data; 2026 struct convert_context *ctx = dmreq->ctx; 2027 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 2028 struct crypt_config *cc = io->cc; 2029 2030 /* 2031 * A request from crypto driver backlog is going to be processed now, 2032 * finish the completion and continue in crypt_convert(). 2033 * (Callback will be called for the second time for this request.) 2034 */ 2035 if (error == -EINPROGRESS) { 2036 complete(&ctx->restart); 2037 return; 2038 } 2039 2040 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post) 2041 error = cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq); 2042 2043 if (error == -EBADMSG) { 2044 char b[BDEVNAME_SIZE]; 2045 DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu", bio_devname(ctx->bio_in, b), 2046 (unsigned long long)le64_to_cpu(*org_sector_of_dmreq(cc, dmreq))); 2047 io->error = BLK_STS_PROTECTION; 2048 } else if (error < 0) 2049 io->error = BLK_STS_IOERR; 2050 2051 crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio); 2052 2053 if (!atomic_dec_and_test(&ctx->cc_pending)) 2054 return; 2055 2056 /* 2057 * The request is fully completed: for inline writes, let 2058 * kcryptd_crypt_write_convert() do the IO submission. 2059 */ 2060 if (bio_data_dir(io->base_bio) == READ) { 2061 kcryptd_crypt_read_done(io); 2062 return; 2063 } 2064 2065 if (kcryptd_crypt_write_inline(cc, ctx)) { 2066 complete(&ctx->restart); 2067 return; 2068 } 2069 2070 kcryptd_crypt_write_io_submit(io, 1); 2071 } 2072 2073 static void kcryptd_crypt(struct work_struct *work) 2074 { 2075 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2076 2077 if (bio_data_dir(io->base_bio) == READ) 2078 kcryptd_crypt_read_convert(io); 2079 else 2080 kcryptd_crypt_write_convert(io); 2081 } 2082 2083 static void kcryptd_crypt_tasklet(unsigned long work) 2084 { 2085 kcryptd_crypt((struct work_struct *)work); 2086 } 2087 2088 static void kcryptd_queue_crypt(struct dm_crypt_io *io) 2089 { 2090 struct crypt_config *cc = io->cc; 2091 2092 if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) || 2093 (bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) { 2094 if (in_irq()) { 2095 /* Crypto API's "skcipher_walk_first() refuses to work in hard IRQ context */ 2096 tasklet_init(&io->tasklet, kcryptd_crypt_tasklet, (unsigned long)&io->work); 2097 tasklet_schedule(&io->tasklet); 2098 return; 2099 } 2100 2101 kcryptd_crypt(&io->work); 2102 return; 2103 } 2104 2105 INIT_WORK(&io->work, kcryptd_crypt); 2106 queue_work(cc->crypt_queue, &io->work); 2107 } 2108 2109 static void crypt_free_tfms_aead(struct crypt_config *cc) 2110 { 2111 if (!cc->cipher_tfm.tfms_aead) 2112 return; 2113 2114 if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2115 crypto_free_aead(cc->cipher_tfm.tfms_aead[0]); 2116 cc->cipher_tfm.tfms_aead[0] = NULL; 2117 } 2118 2119 kfree(cc->cipher_tfm.tfms_aead); 2120 cc->cipher_tfm.tfms_aead = NULL; 2121 } 2122 2123 static void crypt_free_tfms_skcipher(struct crypt_config *cc) 2124 { 2125 unsigned i; 2126 2127 if (!cc->cipher_tfm.tfms) 2128 return; 2129 2130 for (i = 0; i < cc->tfms_count; i++) 2131 if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) { 2132 crypto_free_skcipher(cc->cipher_tfm.tfms[i]); 2133 cc->cipher_tfm.tfms[i] = NULL; 2134 } 2135 2136 kfree(cc->cipher_tfm.tfms); 2137 cc->cipher_tfm.tfms = NULL; 2138 } 2139 2140 static void crypt_free_tfms(struct crypt_config *cc) 2141 { 2142 if (crypt_integrity_aead(cc)) 2143 crypt_free_tfms_aead(cc); 2144 else 2145 crypt_free_tfms_skcipher(cc); 2146 } 2147 2148 static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode) 2149 { 2150 unsigned i; 2151 int err; 2152 2153 cc->cipher_tfm.tfms = kcalloc(cc->tfms_count, 2154 sizeof(struct crypto_skcipher *), 2155 GFP_KERNEL); 2156 if (!cc->cipher_tfm.tfms) 2157 return -ENOMEM; 2158 2159 for (i = 0; i < cc->tfms_count; i++) { 2160 cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0, 2161 CRYPTO_ALG_ALLOCATES_MEMORY); 2162 if (IS_ERR(cc->cipher_tfm.tfms[i])) { 2163 err = PTR_ERR(cc->cipher_tfm.tfms[i]); 2164 crypt_free_tfms(cc); 2165 return err; 2166 } 2167 } 2168 2169 /* 2170 * dm-crypt performance can vary greatly depending on which crypto 2171 * algorithm implementation is used. Help people debug performance 2172 * problems by logging the ->cra_driver_name. 2173 */ 2174 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2175 crypto_skcipher_alg(any_tfm(cc))->base.cra_driver_name); 2176 return 0; 2177 } 2178 2179 static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode) 2180 { 2181 int err; 2182 2183 cc->cipher_tfm.tfms = kmalloc(sizeof(struct crypto_aead *), GFP_KERNEL); 2184 if (!cc->cipher_tfm.tfms) 2185 return -ENOMEM; 2186 2187 cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0, 2188 CRYPTO_ALG_ALLOCATES_MEMORY); 2189 if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2190 err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]); 2191 crypt_free_tfms(cc); 2192 return err; 2193 } 2194 2195 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2196 crypto_aead_alg(any_tfm_aead(cc))->base.cra_driver_name); 2197 return 0; 2198 } 2199 2200 static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode) 2201 { 2202 if (crypt_integrity_aead(cc)) 2203 return crypt_alloc_tfms_aead(cc, ciphermode); 2204 else 2205 return crypt_alloc_tfms_skcipher(cc, ciphermode); 2206 } 2207 2208 static unsigned crypt_subkey_size(struct crypt_config *cc) 2209 { 2210 return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count); 2211 } 2212 2213 static unsigned crypt_authenckey_size(struct crypt_config *cc) 2214 { 2215 return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param)); 2216 } 2217 2218 /* 2219 * If AEAD is composed like authenc(hmac(sha256),xts(aes)), 2220 * the key must be for some reason in special format. 2221 * This funcion converts cc->key to this special format. 2222 */ 2223 static void crypt_copy_authenckey(char *p, const void *key, 2224 unsigned enckeylen, unsigned authkeylen) 2225 { 2226 struct crypto_authenc_key_param *param; 2227 struct rtattr *rta; 2228 2229 rta = (struct rtattr *)p; 2230 param = RTA_DATA(rta); 2231 param->enckeylen = cpu_to_be32(enckeylen); 2232 rta->rta_len = RTA_LENGTH(sizeof(*param)); 2233 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; 2234 p += RTA_SPACE(sizeof(*param)); 2235 memcpy(p, key + enckeylen, authkeylen); 2236 p += authkeylen; 2237 memcpy(p, key, enckeylen); 2238 } 2239 2240 static int crypt_setkey(struct crypt_config *cc) 2241 { 2242 unsigned subkey_size; 2243 int err = 0, i, r; 2244 2245 /* Ignore extra keys (which are used for IV etc) */ 2246 subkey_size = crypt_subkey_size(cc); 2247 2248 if (crypt_integrity_hmac(cc)) { 2249 if (subkey_size < cc->key_mac_size) 2250 return -EINVAL; 2251 2252 crypt_copy_authenckey(cc->authenc_key, cc->key, 2253 subkey_size - cc->key_mac_size, 2254 cc->key_mac_size); 2255 } 2256 2257 for (i = 0; i < cc->tfms_count; i++) { 2258 if (crypt_integrity_hmac(cc)) 2259 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2260 cc->authenc_key, crypt_authenckey_size(cc)); 2261 else if (crypt_integrity_aead(cc)) 2262 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2263 cc->key + (i * subkey_size), 2264 subkey_size); 2265 else 2266 r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i], 2267 cc->key + (i * subkey_size), 2268 subkey_size); 2269 if (r) 2270 err = r; 2271 } 2272 2273 if (crypt_integrity_hmac(cc)) 2274 memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc)); 2275 2276 return err; 2277 } 2278 2279 #ifdef CONFIG_KEYS 2280 2281 static bool contains_whitespace(const char *str) 2282 { 2283 while (*str) 2284 if (isspace(*str++)) 2285 return true; 2286 return false; 2287 } 2288 2289 static int set_key_user(struct crypt_config *cc, struct key *key) 2290 { 2291 const struct user_key_payload *ukp; 2292 2293 ukp = user_key_payload_locked(key); 2294 if (!ukp) 2295 return -EKEYREVOKED; 2296 2297 if (cc->key_size != ukp->datalen) 2298 return -EINVAL; 2299 2300 memcpy(cc->key, ukp->data, cc->key_size); 2301 2302 return 0; 2303 } 2304 2305 #if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE) 2306 static int set_key_encrypted(struct crypt_config *cc, struct key *key) 2307 { 2308 const struct encrypted_key_payload *ekp; 2309 2310 ekp = key->payload.data[0]; 2311 if (!ekp) 2312 return -EKEYREVOKED; 2313 2314 if (cc->key_size != ekp->decrypted_datalen) 2315 return -EINVAL; 2316 2317 memcpy(cc->key, ekp->decrypted_data, cc->key_size); 2318 2319 return 0; 2320 } 2321 #endif /* CONFIG_ENCRYPTED_KEYS */ 2322 2323 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2324 { 2325 char *new_key_string, *key_desc; 2326 int ret; 2327 struct key_type *type; 2328 struct key *key; 2329 int (*set_key)(struct crypt_config *cc, struct key *key); 2330 2331 /* 2332 * Reject key_string with whitespace. dm core currently lacks code for 2333 * proper whitespace escaping in arguments on DM_TABLE_STATUS path. 2334 */ 2335 if (contains_whitespace(key_string)) { 2336 DMERR("whitespace chars not allowed in key string"); 2337 return -EINVAL; 2338 } 2339 2340 /* look for next ':' separating key_type from key_description */ 2341 key_desc = strpbrk(key_string, ":"); 2342 if (!key_desc || key_desc == key_string || !strlen(key_desc + 1)) 2343 return -EINVAL; 2344 2345 if (!strncmp(key_string, "logon:", key_desc - key_string + 1)) { 2346 type = &key_type_logon; 2347 set_key = set_key_user; 2348 } else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) { 2349 type = &key_type_user; 2350 set_key = set_key_user; 2351 #if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE) 2352 } else if (!strncmp(key_string, "encrypted:", key_desc - key_string + 1)) { 2353 type = &key_type_encrypted; 2354 set_key = set_key_encrypted; 2355 #endif 2356 } else { 2357 return -EINVAL; 2358 } 2359 2360 new_key_string = kstrdup(key_string, GFP_KERNEL); 2361 if (!new_key_string) 2362 return -ENOMEM; 2363 2364 key = request_key(type, key_desc + 1, NULL); 2365 if (IS_ERR(key)) { 2366 kfree_sensitive(new_key_string); 2367 return PTR_ERR(key); 2368 } 2369 2370 down_read(&key->sem); 2371 2372 ret = set_key(cc, key); 2373 if (ret < 0) { 2374 up_read(&key->sem); 2375 key_put(key); 2376 kfree_sensitive(new_key_string); 2377 return ret; 2378 } 2379 2380 up_read(&key->sem); 2381 key_put(key); 2382 2383 /* clear the flag since following operations may invalidate previously valid key */ 2384 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2385 2386 ret = crypt_setkey(cc); 2387 2388 if (!ret) { 2389 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2390 kfree_sensitive(cc->key_string); 2391 cc->key_string = new_key_string; 2392 } else 2393 kfree_sensitive(new_key_string); 2394 2395 return ret; 2396 } 2397 2398 static int get_key_size(char **key_string) 2399 { 2400 char *colon, dummy; 2401 int ret; 2402 2403 if (*key_string[0] != ':') 2404 return strlen(*key_string) >> 1; 2405 2406 /* look for next ':' in key string */ 2407 colon = strpbrk(*key_string + 1, ":"); 2408 if (!colon) 2409 return -EINVAL; 2410 2411 if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':') 2412 return -EINVAL; 2413 2414 *key_string = colon; 2415 2416 /* remaining key string should be :<logon|user>:<key_desc> */ 2417 2418 return ret; 2419 } 2420 2421 #else 2422 2423 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2424 { 2425 return -EINVAL; 2426 } 2427 2428 static int get_key_size(char **key_string) 2429 { 2430 return (*key_string[0] == ':') ? -EINVAL : strlen(*key_string) >> 1; 2431 } 2432 2433 #endif /* CONFIG_KEYS */ 2434 2435 static int crypt_set_key(struct crypt_config *cc, char *key) 2436 { 2437 int r = -EINVAL; 2438 int key_string_len = strlen(key); 2439 2440 /* Hyphen (which gives a key_size of zero) means there is no key. */ 2441 if (!cc->key_size && strcmp(key, "-")) 2442 goto out; 2443 2444 /* ':' means the key is in kernel keyring, short-circuit normal key processing */ 2445 if (key[0] == ':') { 2446 r = crypt_set_keyring_key(cc, key + 1); 2447 goto out; 2448 } 2449 2450 /* clear the flag since following operations may invalidate previously valid key */ 2451 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2452 2453 /* wipe references to any kernel keyring key */ 2454 kfree_sensitive(cc->key_string); 2455 cc->key_string = NULL; 2456 2457 /* Decode key from its hex representation. */ 2458 if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0) 2459 goto out; 2460 2461 r = crypt_setkey(cc); 2462 if (!r) 2463 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2464 2465 out: 2466 /* Hex key string not needed after here, so wipe it. */ 2467 memset(key, '0', key_string_len); 2468 2469 return r; 2470 } 2471 2472 static int crypt_wipe_key(struct crypt_config *cc) 2473 { 2474 int r; 2475 2476 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2477 get_random_bytes(&cc->key, cc->key_size); 2478 2479 /* Wipe IV private keys */ 2480 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) { 2481 r = cc->iv_gen_ops->wipe(cc); 2482 if (r) 2483 return r; 2484 } 2485 2486 kfree_sensitive(cc->key_string); 2487 cc->key_string = NULL; 2488 r = crypt_setkey(cc); 2489 memset(&cc->key, 0, cc->key_size * sizeof(u8)); 2490 2491 return r; 2492 } 2493 2494 static void crypt_calculate_pages_per_client(void) 2495 { 2496 unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100; 2497 2498 if (!dm_crypt_clients_n) 2499 return; 2500 2501 pages /= dm_crypt_clients_n; 2502 if (pages < DM_CRYPT_MIN_PAGES_PER_CLIENT) 2503 pages = DM_CRYPT_MIN_PAGES_PER_CLIENT; 2504 dm_crypt_pages_per_client = pages; 2505 } 2506 2507 static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data) 2508 { 2509 struct crypt_config *cc = pool_data; 2510 struct page *page; 2511 2512 if (unlikely(percpu_counter_compare(&cc->n_allocated_pages, dm_crypt_pages_per_client) >= 0) && 2513 likely(gfp_mask & __GFP_NORETRY)) 2514 return NULL; 2515 2516 page = alloc_page(gfp_mask); 2517 if (likely(page != NULL)) 2518 percpu_counter_add(&cc->n_allocated_pages, 1); 2519 2520 return page; 2521 } 2522 2523 static void crypt_page_free(void *page, void *pool_data) 2524 { 2525 struct crypt_config *cc = pool_data; 2526 2527 __free_page(page); 2528 percpu_counter_sub(&cc->n_allocated_pages, 1); 2529 } 2530 2531 static void crypt_dtr(struct dm_target *ti) 2532 { 2533 struct crypt_config *cc = ti->private; 2534 2535 ti->private = NULL; 2536 2537 if (!cc) 2538 return; 2539 2540 if (cc->write_thread) 2541 kthread_stop(cc->write_thread); 2542 2543 if (cc->io_queue) 2544 destroy_workqueue(cc->io_queue); 2545 if (cc->crypt_queue) 2546 destroy_workqueue(cc->crypt_queue); 2547 2548 crypt_free_tfms(cc); 2549 2550 bioset_exit(&cc->bs); 2551 2552 mempool_exit(&cc->page_pool); 2553 mempool_exit(&cc->req_pool); 2554 mempool_exit(&cc->tag_pool); 2555 2556 WARN_ON(percpu_counter_sum(&cc->n_allocated_pages) != 0); 2557 percpu_counter_destroy(&cc->n_allocated_pages); 2558 2559 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) 2560 cc->iv_gen_ops->dtr(cc); 2561 2562 if (cc->dev) 2563 dm_put_device(ti, cc->dev); 2564 2565 kfree_sensitive(cc->cipher_string); 2566 kfree_sensitive(cc->key_string); 2567 kfree_sensitive(cc->cipher_auth); 2568 kfree_sensitive(cc->authenc_key); 2569 2570 mutex_destroy(&cc->bio_alloc_lock); 2571 2572 /* Must zero key material before freeing */ 2573 kfree_sensitive(cc); 2574 2575 spin_lock(&dm_crypt_clients_lock); 2576 WARN_ON(!dm_crypt_clients_n); 2577 dm_crypt_clients_n--; 2578 crypt_calculate_pages_per_client(); 2579 spin_unlock(&dm_crypt_clients_lock); 2580 } 2581 2582 static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode) 2583 { 2584 struct crypt_config *cc = ti->private; 2585 2586 if (crypt_integrity_aead(cc)) 2587 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2588 else 2589 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2590 2591 if (cc->iv_size) 2592 /* at least a 64 bit sector number should fit in our buffer */ 2593 cc->iv_size = max(cc->iv_size, 2594 (unsigned int)(sizeof(u64) / sizeof(u8))); 2595 else if (ivmode) { 2596 DMWARN("Selected cipher does not support IVs"); 2597 ivmode = NULL; 2598 } 2599 2600 /* Choose ivmode, see comments at iv code. */ 2601 if (ivmode == NULL) 2602 cc->iv_gen_ops = NULL; 2603 else if (strcmp(ivmode, "plain") == 0) 2604 cc->iv_gen_ops = &crypt_iv_plain_ops; 2605 else if (strcmp(ivmode, "plain64") == 0) 2606 cc->iv_gen_ops = &crypt_iv_plain64_ops; 2607 else if (strcmp(ivmode, "plain64be") == 0) 2608 cc->iv_gen_ops = &crypt_iv_plain64be_ops; 2609 else if (strcmp(ivmode, "essiv") == 0) 2610 cc->iv_gen_ops = &crypt_iv_essiv_ops; 2611 else if (strcmp(ivmode, "benbi") == 0) 2612 cc->iv_gen_ops = &crypt_iv_benbi_ops; 2613 else if (strcmp(ivmode, "null") == 0) 2614 cc->iv_gen_ops = &crypt_iv_null_ops; 2615 else if (strcmp(ivmode, "eboiv") == 0) 2616 cc->iv_gen_ops = &crypt_iv_eboiv_ops; 2617 else if (strcmp(ivmode, "elephant") == 0) { 2618 cc->iv_gen_ops = &crypt_iv_elephant_ops; 2619 cc->key_parts = 2; 2620 cc->key_extra_size = cc->key_size / 2; 2621 if (cc->key_extra_size > ELEPHANT_MAX_KEY_SIZE) 2622 return -EINVAL; 2623 set_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags); 2624 } else if (strcmp(ivmode, "lmk") == 0) { 2625 cc->iv_gen_ops = &crypt_iv_lmk_ops; 2626 /* 2627 * Version 2 and 3 is recognised according 2628 * to length of provided multi-key string. 2629 * If present (version 3), last key is used as IV seed. 2630 * All keys (including IV seed) are always the same size. 2631 */ 2632 if (cc->key_size % cc->key_parts) { 2633 cc->key_parts++; 2634 cc->key_extra_size = cc->key_size / cc->key_parts; 2635 } 2636 } else if (strcmp(ivmode, "tcw") == 0) { 2637 cc->iv_gen_ops = &crypt_iv_tcw_ops; 2638 cc->key_parts += 2; /* IV + whitening */ 2639 cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE; 2640 } else if (strcmp(ivmode, "random") == 0) { 2641 cc->iv_gen_ops = &crypt_iv_random_ops; 2642 /* Need storage space in integrity fields. */ 2643 cc->integrity_iv_size = cc->iv_size; 2644 } else { 2645 ti->error = "Invalid IV mode"; 2646 return -EINVAL; 2647 } 2648 2649 return 0; 2650 } 2651 2652 /* 2653 * Workaround to parse HMAC algorithm from AEAD crypto API spec. 2654 * The HMAC is needed to calculate tag size (HMAC digest size). 2655 * This should be probably done by crypto-api calls (once available...) 2656 */ 2657 static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api) 2658 { 2659 char *start, *end, *mac_alg = NULL; 2660 struct crypto_ahash *mac; 2661 2662 if (!strstarts(cipher_api, "authenc(")) 2663 return 0; 2664 2665 start = strchr(cipher_api, '('); 2666 end = strchr(cipher_api, ','); 2667 if (!start || !end || ++start > end) 2668 return -EINVAL; 2669 2670 mac_alg = kzalloc(end - start + 1, GFP_KERNEL); 2671 if (!mac_alg) 2672 return -ENOMEM; 2673 strncpy(mac_alg, start, end - start); 2674 2675 mac = crypto_alloc_ahash(mac_alg, 0, CRYPTO_ALG_ALLOCATES_MEMORY); 2676 kfree(mac_alg); 2677 2678 if (IS_ERR(mac)) 2679 return PTR_ERR(mac); 2680 2681 cc->key_mac_size = crypto_ahash_digestsize(mac); 2682 crypto_free_ahash(mac); 2683 2684 cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL); 2685 if (!cc->authenc_key) 2686 return -ENOMEM; 2687 2688 return 0; 2689 } 2690 2691 static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key, 2692 char **ivmode, char **ivopts) 2693 { 2694 struct crypt_config *cc = ti->private; 2695 char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME]; 2696 int ret = -EINVAL; 2697 2698 cc->tfms_count = 1; 2699 2700 /* 2701 * New format (capi: prefix) 2702 * capi:cipher_api_spec-iv:ivopts 2703 */ 2704 tmp = &cipher_in[strlen("capi:")]; 2705 2706 /* Separate IV options if present, it can contain another '-' in hash name */ 2707 *ivopts = strrchr(tmp, ':'); 2708 if (*ivopts) { 2709 **ivopts = '\0'; 2710 (*ivopts)++; 2711 } 2712 /* Parse IV mode */ 2713 *ivmode = strrchr(tmp, '-'); 2714 if (*ivmode) { 2715 **ivmode = '\0'; 2716 (*ivmode)++; 2717 } 2718 /* The rest is crypto API spec */ 2719 cipher_api = tmp; 2720 2721 /* Alloc AEAD, can be used only in new format. */ 2722 if (crypt_integrity_aead(cc)) { 2723 ret = crypt_ctr_auth_cipher(cc, cipher_api); 2724 if (ret < 0) { 2725 ti->error = "Invalid AEAD cipher spec"; 2726 return -ENOMEM; 2727 } 2728 } 2729 2730 if (*ivmode && !strcmp(*ivmode, "lmk")) 2731 cc->tfms_count = 64; 2732 2733 if (*ivmode && !strcmp(*ivmode, "essiv")) { 2734 if (!*ivopts) { 2735 ti->error = "Digest algorithm missing for ESSIV mode"; 2736 return -EINVAL; 2737 } 2738 ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)", 2739 cipher_api, *ivopts); 2740 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 2741 ti->error = "Cannot allocate cipher string"; 2742 return -ENOMEM; 2743 } 2744 cipher_api = buf; 2745 } 2746 2747 cc->key_parts = cc->tfms_count; 2748 2749 /* Allocate cipher */ 2750 ret = crypt_alloc_tfms(cc, cipher_api); 2751 if (ret < 0) { 2752 ti->error = "Error allocating crypto tfm"; 2753 return ret; 2754 } 2755 2756 if (crypt_integrity_aead(cc)) 2757 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2758 else 2759 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2760 2761 return 0; 2762 } 2763 2764 static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key, 2765 char **ivmode, char **ivopts) 2766 { 2767 struct crypt_config *cc = ti->private; 2768 char *tmp, *cipher, *chainmode, *keycount; 2769 char *cipher_api = NULL; 2770 int ret = -EINVAL; 2771 char dummy; 2772 2773 if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) { 2774 ti->error = "Bad cipher specification"; 2775 return -EINVAL; 2776 } 2777 2778 /* 2779 * Legacy dm-crypt cipher specification 2780 * cipher[:keycount]-mode-iv:ivopts 2781 */ 2782 tmp = cipher_in; 2783 keycount = strsep(&tmp, "-"); 2784 cipher = strsep(&keycount, ":"); 2785 2786 if (!keycount) 2787 cc->tfms_count = 1; 2788 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 || 2789 !is_power_of_2(cc->tfms_count)) { 2790 ti->error = "Bad cipher key count specification"; 2791 return -EINVAL; 2792 } 2793 cc->key_parts = cc->tfms_count; 2794 2795 chainmode = strsep(&tmp, "-"); 2796 *ivmode = strsep(&tmp, ":"); 2797 *ivopts = tmp; 2798 2799 /* 2800 * For compatibility with the original dm-crypt mapping format, if 2801 * only the cipher name is supplied, use cbc-plain. 2802 */ 2803 if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) { 2804 chainmode = "cbc"; 2805 *ivmode = "plain"; 2806 } 2807 2808 if (strcmp(chainmode, "ecb") && !*ivmode) { 2809 ti->error = "IV mechanism required"; 2810 return -EINVAL; 2811 } 2812 2813 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL); 2814 if (!cipher_api) 2815 goto bad_mem; 2816 2817 if (*ivmode && !strcmp(*ivmode, "essiv")) { 2818 if (!*ivopts) { 2819 ti->error = "Digest algorithm missing for ESSIV mode"; 2820 kfree(cipher_api); 2821 return -EINVAL; 2822 } 2823 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 2824 "essiv(%s(%s),%s)", chainmode, cipher, *ivopts); 2825 } else { 2826 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 2827 "%s(%s)", chainmode, cipher); 2828 } 2829 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 2830 kfree(cipher_api); 2831 goto bad_mem; 2832 } 2833 2834 /* Allocate cipher */ 2835 ret = crypt_alloc_tfms(cc, cipher_api); 2836 if (ret < 0) { 2837 ti->error = "Error allocating crypto tfm"; 2838 kfree(cipher_api); 2839 return ret; 2840 } 2841 kfree(cipher_api); 2842 2843 return 0; 2844 bad_mem: 2845 ti->error = "Cannot allocate cipher strings"; 2846 return -ENOMEM; 2847 } 2848 2849 static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key) 2850 { 2851 struct crypt_config *cc = ti->private; 2852 char *ivmode = NULL, *ivopts = NULL; 2853 int ret; 2854 2855 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL); 2856 if (!cc->cipher_string) { 2857 ti->error = "Cannot allocate cipher strings"; 2858 return -ENOMEM; 2859 } 2860 2861 if (strstarts(cipher_in, "capi:")) 2862 ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts); 2863 else 2864 ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts); 2865 if (ret) 2866 return ret; 2867 2868 /* Initialize IV */ 2869 ret = crypt_ctr_ivmode(ti, ivmode); 2870 if (ret < 0) 2871 return ret; 2872 2873 /* Initialize and set key */ 2874 ret = crypt_set_key(cc, key); 2875 if (ret < 0) { 2876 ti->error = "Error decoding and setting key"; 2877 return ret; 2878 } 2879 2880 /* Allocate IV */ 2881 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) { 2882 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts); 2883 if (ret < 0) { 2884 ti->error = "Error creating IV"; 2885 return ret; 2886 } 2887 } 2888 2889 /* Initialize IV (set keys for ESSIV etc) */ 2890 if (cc->iv_gen_ops && cc->iv_gen_ops->init) { 2891 ret = cc->iv_gen_ops->init(cc); 2892 if (ret < 0) { 2893 ti->error = "Error initialising IV"; 2894 return ret; 2895 } 2896 } 2897 2898 /* wipe the kernel key payload copy */ 2899 if (cc->key_string) 2900 memset(cc->key, 0, cc->key_size * sizeof(u8)); 2901 2902 return ret; 2903 } 2904 2905 static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv) 2906 { 2907 struct crypt_config *cc = ti->private; 2908 struct dm_arg_set as; 2909 static const struct dm_arg _args[] = { 2910 {0, 8, "Invalid number of feature args"}, 2911 }; 2912 unsigned int opt_params, val; 2913 const char *opt_string, *sval; 2914 char dummy; 2915 int ret; 2916 2917 /* Optional parameters */ 2918 as.argc = argc; 2919 as.argv = argv; 2920 2921 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error); 2922 if (ret) 2923 return ret; 2924 2925 while (opt_params--) { 2926 opt_string = dm_shift_arg(&as); 2927 if (!opt_string) { 2928 ti->error = "Not enough feature arguments"; 2929 return -EINVAL; 2930 } 2931 2932 if (!strcasecmp(opt_string, "allow_discards")) 2933 ti->num_discard_bios = 1; 2934 2935 else if (!strcasecmp(opt_string, "same_cpu_crypt")) 2936 set_bit(DM_CRYPT_SAME_CPU, &cc->flags); 2937 2938 else if (!strcasecmp(opt_string, "submit_from_crypt_cpus")) 2939 set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 2940 else if (!strcasecmp(opt_string, "no_read_workqueue")) 2941 set_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 2942 else if (!strcasecmp(opt_string, "no_write_workqueue")) 2943 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 2944 else if (sscanf(opt_string, "integrity:%u:", &val) == 1) { 2945 if (val == 0 || val > MAX_TAG_SIZE) { 2946 ti->error = "Invalid integrity arguments"; 2947 return -EINVAL; 2948 } 2949 cc->on_disk_tag_size = val; 2950 sval = strchr(opt_string + strlen("integrity:"), ':') + 1; 2951 if (!strcasecmp(sval, "aead")) { 2952 set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 2953 } else if (strcasecmp(sval, "none")) { 2954 ti->error = "Unknown integrity profile"; 2955 return -EINVAL; 2956 } 2957 2958 cc->cipher_auth = kstrdup(sval, GFP_KERNEL); 2959 if (!cc->cipher_auth) 2960 return -ENOMEM; 2961 } else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) { 2962 if (cc->sector_size < (1 << SECTOR_SHIFT) || 2963 cc->sector_size > 4096 || 2964 (cc->sector_size & (cc->sector_size - 1))) { 2965 ti->error = "Invalid feature value for sector_size"; 2966 return -EINVAL; 2967 } 2968 if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) { 2969 ti->error = "Device size is not multiple of sector_size feature"; 2970 return -EINVAL; 2971 } 2972 cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT; 2973 } else if (!strcasecmp(opt_string, "iv_large_sectors")) 2974 set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 2975 else { 2976 ti->error = "Invalid feature arguments"; 2977 return -EINVAL; 2978 } 2979 } 2980 2981 return 0; 2982 } 2983 2984 #ifdef CONFIG_BLK_DEV_ZONED 2985 2986 static int crypt_report_zones(struct dm_target *ti, 2987 struct dm_report_zones_args *args, unsigned int nr_zones) 2988 { 2989 struct crypt_config *cc = ti->private; 2990 sector_t sector = cc->start + dm_target_offset(ti, args->next_sector); 2991 2992 args->start = cc->start; 2993 return blkdev_report_zones(cc->dev->bdev, sector, nr_zones, 2994 dm_report_zones_cb, args); 2995 } 2996 2997 #endif 2998 2999 /* 3000 * Construct an encryption mapping: 3001 * <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start> 3002 */ 3003 static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) 3004 { 3005 struct crypt_config *cc; 3006 const char *devname = dm_table_device_name(ti->table); 3007 int key_size; 3008 unsigned int align_mask; 3009 unsigned long long tmpll; 3010 int ret; 3011 size_t iv_size_padding, additional_req_size; 3012 char dummy; 3013 3014 if (argc < 5) { 3015 ti->error = "Not enough arguments"; 3016 return -EINVAL; 3017 } 3018 3019 key_size = get_key_size(&argv[1]); 3020 if (key_size < 0) { 3021 ti->error = "Cannot parse key size"; 3022 return -EINVAL; 3023 } 3024 3025 cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL); 3026 if (!cc) { 3027 ti->error = "Cannot allocate encryption context"; 3028 return -ENOMEM; 3029 } 3030 cc->key_size = key_size; 3031 cc->sector_size = (1 << SECTOR_SHIFT); 3032 cc->sector_shift = 0; 3033 3034 ti->private = cc; 3035 3036 spin_lock(&dm_crypt_clients_lock); 3037 dm_crypt_clients_n++; 3038 crypt_calculate_pages_per_client(); 3039 spin_unlock(&dm_crypt_clients_lock); 3040 3041 ret = percpu_counter_init(&cc->n_allocated_pages, 0, GFP_KERNEL); 3042 if (ret < 0) 3043 goto bad; 3044 3045 /* Optional parameters need to be read before cipher constructor */ 3046 if (argc > 5) { 3047 ret = crypt_ctr_optional(ti, argc - 5, &argv[5]); 3048 if (ret) 3049 goto bad; 3050 } 3051 3052 ret = crypt_ctr_cipher(ti, argv[0], argv[1]); 3053 if (ret < 0) 3054 goto bad; 3055 3056 if (crypt_integrity_aead(cc)) { 3057 cc->dmreq_start = sizeof(struct aead_request); 3058 cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc)); 3059 align_mask = crypto_aead_alignmask(any_tfm_aead(cc)); 3060 } else { 3061 cc->dmreq_start = sizeof(struct skcipher_request); 3062 cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc)); 3063 align_mask = crypto_skcipher_alignmask(any_tfm(cc)); 3064 } 3065 cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request)); 3066 3067 if (align_mask < CRYPTO_MINALIGN) { 3068 /* Allocate the padding exactly */ 3069 iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request)) 3070 & align_mask; 3071 } else { 3072 /* 3073 * If the cipher requires greater alignment than kmalloc 3074 * alignment, we don't know the exact position of the 3075 * initialization vector. We must assume worst case. 3076 */ 3077 iv_size_padding = align_mask; 3078 } 3079 3080 /* ...| IV + padding | original IV | original sec. number | bio tag offset | */ 3081 additional_req_size = sizeof(struct dm_crypt_request) + 3082 iv_size_padding + cc->iv_size + 3083 cc->iv_size + 3084 sizeof(uint64_t) + 3085 sizeof(unsigned int); 3086 3087 ret = mempool_init_kmalloc_pool(&cc->req_pool, MIN_IOS, cc->dmreq_start + additional_req_size); 3088 if (ret) { 3089 ti->error = "Cannot allocate crypt request mempool"; 3090 goto bad; 3091 } 3092 3093 cc->per_bio_data_size = ti->per_io_data_size = 3094 ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size, 3095 ARCH_KMALLOC_MINALIGN); 3096 3097 ret = mempool_init(&cc->page_pool, BIO_MAX_PAGES, crypt_page_alloc, crypt_page_free, cc); 3098 if (ret) { 3099 ti->error = "Cannot allocate page mempool"; 3100 goto bad; 3101 } 3102 3103 ret = bioset_init(&cc->bs, MIN_IOS, 0, BIOSET_NEED_BVECS); 3104 if (ret) { 3105 ti->error = "Cannot allocate crypt bioset"; 3106 goto bad; 3107 } 3108 3109 mutex_init(&cc->bio_alloc_lock); 3110 3111 ret = -EINVAL; 3112 if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) || 3113 (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) { 3114 ti->error = "Invalid iv_offset sector"; 3115 goto bad; 3116 } 3117 cc->iv_offset = tmpll; 3118 3119 ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev); 3120 if (ret) { 3121 ti->error = "Device lookup failed"; 3122 goto bad; 3123 } 3124 3125 ret = -EINVAL; 3126 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) { 3127 ti->error = "Invalid device sector"; 3128 goto bad; 3129 } 3130 cc->start = tmpll; 3131 3132 /* 3133 * For zoned block devices, we need to preserve the issuer write 3134 * ordering. To do so, disable write workqueues and force inline 3135 * encryption completion. 3136 */ 3137 if (bdev_is_zoned(cc->dev->bdev)) { 3138 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3139 set_bit(DM_CRYPT_WRITE_INLINE, &cc->flags); 3140 } 3141 3142 if (crypt_integrity_aead(cc) || cc->integrity_iv_size) { 3143 ret = crypt_integrity_ctr(cc, ti); 3144 if (ret) 3145 goto bad; 3146 3147 cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->on_disk_tag_size; 3148 if (!cc->tag_pool_max_sectors) 3149 cc->tag_pool_max_sectors = 1; 3150 3151 ret = mempool_init_kmalloc_pool(&cc->tag_pool, MIN_IOS, 3152 cc->tag_pool_max_sectors * cc->on_disk_tag_size); 3153 if (ret) { 3154 ti->error = "Cannot allocate integrity tags mempool"; 3155 goto bad; 3156 } 3157 3158 cc->tag_pool_max_sectors <<= cc->sector_shift; 3159 } 3160 3161 ret = -ENOMEM; 3162 cc->io_queue = alloc_workqueue("kcryptd_io/%s", WQ_MEM_RECLAIM, 1, devname); 3163 if (!cc->io_queue) { 3164 ti->error = "Couldn't create kcryptd io queue"; 3165 goto bad; 3166 } 3167 3168 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3169 cc->crypt_queue = alloc_workqueue("kcryptd/%s", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 3170 1, devname); 3171 else 3172 cc->crypt_queue = alloc_workqueue("kcryptd/%s", 3173 WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND, 3174 num_online_cpus(), devname); 3175 if (!cc->crypt_queue) { 3176 ti->error = "Couldn't create kcryptd queue"; 3177 goto bad; 3178 } 3179 3180 spin_lock_init(&cc->write_thread_lock); 3181 cc->write_tree = RB_ROOT; 3182 3183 cc->write_thread = kthread_create(dmcrypt_write, cc, "dmcrypt_write/%s", devname); 3184 if (IS_ERR(cc->write_thread)) { 3185 ret = PTR_ERR(cc->write_thread); 3186 cc->write_thread = NULL; 3187 ti->error = "Couldn't spawn write thread"; 3188 goto bad; 3189 } 3190 wake_up_process(cc->write_thread); 3191 3192 ti->num_flush_bios = 1; 3193 3194 return 0; 3195 3196 bad: 3197 crypt_dtr(ti); 3198 return ret; 3199 } 3200 3201 static int crypt_map(struct dm_target *ti, struct bio *bio) 3202 { 3203 struct dm_crypt_io *io; 3204 struct crypt_config *cc = ti->private; 3205 3206 /* 3207 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues. 3208 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight 3209 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters 3210 */ 3211 if (unlikely(bio->bi_opf & REQ_PREFLUSH || 3212 bio_op(bio) == REQ_OP_DISCARD)) { 3213 bio_set_dev(bio, cc->dev->bdev); 3214 if (bio_sectors(bio)) 3215 bio->bi_iter.bi_sector = cc->start + 3216 dm_target_offset(ti, bio->bi_iter.bi_sector); 3217 return DM_MAPIO_REMAPPED; 3218 } 3219 3220 /* 3221 * Check if bio is too large, split as needed. 3222 */ 3223 if (unlikely(bio->bi_iter.bi_size > (BIO_MAX_PAGES << PAGE_SHIFT)) && 3224 (bio_data_dir(bio) == WRITE || cc->on_disk_tag_size)) 3225 dm_accept_partial_bio(bio, ((BIO_MAX_PAGES << PAGE_SHIFT) >> SECTOR_SHIFT)); 3226 3227 /* 3228 * Ensure that bio is a multiple of internal sector encryption size 3229 * and is aligned to this size as defined in IO hints. 3230 */ 3231 if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0)) 3232 return DM_MAPIO_KILL; 3233 3234 if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1))) 3235 return DM_MAPIO_KILL; 3236 3237 io = dm_per_bio_data(bio, cc->per_bio_data_size); 3238 crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector)); 3239 3240 if (cc->on_disk_tag_size) { 3241 unsigned tag_len = cc->on_disk_tag_size * (bio_sectors(bio) >> cc->sector_shift); 3242 3243 if (unlikely(tag_len > KMALLOC_MAX_SIZE) || 3244 unlikely(!(io->integrity_metadata = kmalloc(tag_len, 3245 GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN)))) { 3246 if (bio_sectors(bio) > cc->tag_pool_max_sectors) 3247 dm_accept_partial_bio(bio, cc->tag_pool_max_sectors); 3248 io->integrity_metadata = mempool_alloc(&cc->tag_pool, GFP_NOIO); 3249 io->integrity_metadata_from_pool = true; 3250 } 3251 } 3252 3253 if (crypt_integrity_aead(cc)) 3254 io->ctx.r.req_aead = (struct aead_request *)(io + 1); 3255 else 3256 io->ctx.r.req = (struct skcipher_request *)(io + 1); 3257 3258 if (bio_data_dir(io->base_bio) == READ) { 3259 if (kcryptd_io_read(io, GFP_NOWAIT)) 3260 kcryptd_queue_read(io); 3261 } else 3262 kcryptd_queue_crypt(io); 3263 3264 return DM_MAPIO_SUBMITTED; 3265 } 3266 3267 static void crypt_status(struct dm_target *ti, status_type_t type, 3268 unsigned status_flags, char *result, unsigned maxlen) 3269 { 3270 struct crypt_config *cc = ti->private; 3271 unsigned i, sz = 0; 3272 int num_feature_args = 0; 3273 3274 switch (type) { 3275 case STATUSTYPE_INFO: 3276 result[0] = '\0'; 3277 break; 3278 3279 case STATUSTYPE_TABLE: 3280 DMEMIT("%s ", cc->cipher_string); 3281 3282 if (cc->key_size > 0) { 3283 if (cc->key_string) 3284 DMEMIT(":%u:%s", cc->key_size, cc->key_string); 3285 else 3286 for (i = 0; i < cc->key_size; i++) 3287 DMEMIT("%02x", cc->key[i]); 3288 } else 3289 DMEMIT("-"); 3290 3291 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, 3292 cc->dev->name, (unsigned long long)cc->start); 3293 3294 num_feature_args += !!ti->num_discard_bios; 3295 num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3296 num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3297 num_feature_args += test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3298 num_feature_args += test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3299 num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT); 3300 num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3301 if (cc->on_disk_tag_size) 3302 num_feature_args++; 3303 if (num_feature_args) { 3304 DMEMIT(" %d", num_feature_args); 3305 if (ti->num_discard_bios) 3306 DMEMIT(" allow_discards"); 3307 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3308 DMEMIT(" same_cpu_crypt"); 3309 if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) 3310 DMEMIT(" submit_from_crypt_cpus"); 3311 if (test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) 3312 DMEMIT(" no_read_workqueue"); 3313 if (test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) 3314 DMEMIT(" no_write_workqueue"); 3315 if (cc->on_disk_tag_size) 3316 DMEMIT(" integrity:%u:%s", cc->on_disk_tag_size, cc->cipher_auth); 3317 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3318 DMEMIT(" sector_size:%d", cc->sector_size); 3319 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 3320 DMEMIT(" iv_large_sectors"); 3321 } 3322 3323 break; 3324 } 3325 } 3326 3327 static void crypt_postsuspend(struct dm_target *ti) 3328 { 3329 struct crypt_config *cc = ti->private; 3330 3331 set_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3332 } 3333 3334 static int crypt_preresume(struct dm_target *ti) 3335 { 3336 struct crypt_config *cc = ti->private; 3337 3338 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { 3339 DMERR("aborting resume - crypt key is not set."); 3340 return -EAGAIN; 3341 } 3342 3343 return 0; 3344 } 3345 3346 static void crypt_resume(struct dm_target *ti) 3347 { 3348 struct crypt_config *cc = ti->private; 3349 3350 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3351 } 3352 3353 /* Message interface 3354 * key set <key> 3355 * key wipe 3356 */ 3357 static int crypt_message(struct dm_target *ti, unsigned argc, char **argv, 3358 char *result, unsigned maxlen) 3359 { 3360 struct crypt_config *cc = ti->private; 3361 int key_size, ret = -EINVAL; 3362 3363 if (argc < 2) 3364 goto error; 3365 3366 if (!strcasecmp(argv[0], "key")) { 3367 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { 3368 DMWARN("not suspended during key manipulation."); 3369 return -EINVAL; 3370 } 3371 if (argc == 3 && !strcasecmp(argv[1], "set")) { 3372 /* The key size may not be changed. */ 3373 key_size = get_key_size(&argv[2]); 3374 if (key_size < 0 || cc->key_size != key_size) { 3375 memset(argv[2], '0', strlen(argv[2])); 3376 return -EINVAL; 3377 } 3378 3379 ret = crypt_set_key(cc, argv[2]); 3380 if (ret) 3381 return ret; 3382 if (cc->iv_gen_ops && cc->iv_gen_ops->init) 3383 ret = cc->iv_gen_ops->init(cc); 3384 /* wipe the kernel key payload copy */ 3385 if (cc->key_string) 3386 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3387 return ret; 3388 } 3389 if (argc == 2 && !strcasecmp(argv[1], "wipe")) 3390 return crypt_wipe_key(cc); 3391 } 3392 3393 error: 3394 DMWARN("unrecognised message received."); 3395 return -EINVAL; 3396 } 3397 3398 static int crypt_iterate_devices(struct dm_target *ti, 3399 iterate_devices_callout_fn fn, void *data) 3400 { 3401 struct crypt_config *cc = ti->private; 3402 3403 return fn(ti, cc->dev, cc->start, ti->len, data); 3404 } 3405 3406 static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits) 3407 { 3408 struct crypt_config *cc = ti->private; 3409 3410 /* 3411 * Unfortunate constraint that is required to avoid the potential 3412 * for exceeding underlying device's max_segments limits -- due to 3413 * crypt_alloc_buffer() possibly allocating pages for the encryption 3414 * bio that are not as physically contiguous as the original bio. 3415 */ 3416 limits->max_segment_size = PAGE_SIZE; 3417 3418 limits->logical_block_size = 3419 max_t(unsigned, limits->logical_block_size, cc->sector_size); 3420 limits->physical_block_size = 3421 max_t(unsigned, limits->physical_block_size, cc->sector_size); 3422 limits->io_min = max_t(unsigned, limits->io_min, cc->sector_size); 3423 } 3424 3425 static struct target_type crypt_target = { 3426 .name = "crypt", 3427 .version = {1, 22, 0}, 3428 .module = THIS_MODULE, 3429 .ctr = crypt_ctr, 3430 .dtr = crypt_dtr, 3431 #ifdef CONFIG_BLK_DEV_ZONED 3432 .features = DM_TARGET_ZONED_HM, 3433 .report_zones = crypt_report_zones, 3434 #endif 3435 .map = crypt_map, 3436 .status = crypt_status, 3437 .postsuspend = crypt_postsuspend, 3438 .preresume = crypt_preresume, 3439 .resume = crypt_resume, 3440 .message = crypt_message, 3441 .iterate_devices = crypt_iterate_devices, 3442 .io_hints = crypt_io_hints, 3443 }; 3444 3445 static int __init dm_crypt_init(void) 3446 { 3447 int r; 3448 3449 r = dm_register_target(&crypt_target); 3450 if (r < 0) 3451 DMERR("register failed %d", r); 3452 3453 return r; 3454 } 3455 3456 static void __exit dm_crypt_exit(void) 3457 { 3458 dm_unregister_target(&crypt_target); 3459 } 3460 3461 module_init(dm_crypt_init); 3462 module_exit(dm_crypt_exit); 3463 3464 MODULE_AUTHOR("Jana Saout <jana@saout.de>"); 3465 MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); 3466 MODULE_LICENSE("GPL"); 3467