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 int 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, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1464 if (!ctx->r.req) 1465 return -ENOMEM; 1466 } 1467 1468 skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]); 1469 1470 /* 1471 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1472 * requests if driver request queue is full. 1473 */ 1474 skcipher_request_set_callback(ctx->r.req, 1475 CRYPTO_TFM_REQ_MAY_BACKLOG, 1476 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req)); 1477 1478 return 0; 1479 } 1480 1481 static int crypt_alloc_req_aead(struct crypt_config *cc, 1482 struct convert_context *ctx) 1483 { 1484 if (!ctx->r.req_aead) { 1485 ctx->r.req_aead = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1486 if (!ctx->r.req_aead) 1487 return -ENOMEM; 1488 } 1489 1490 aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]); 1491 1492 /* 1493 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1494 * requests if driver request queue is full. 1495 */ 1496 aead_request_set_callback(ctx->r.req_aead, 1497 CRYPTO_TFM_REQ_MAY_BACKLOG, 1498 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead)); 1499 1500 return 0; 1501 } 1502 1503 static int crypt_alloc_req(struct crypt_config *cc, 1504 struct convert_context *ctx) 1505 { 1506 if (crypt_integrity_aead(cc)) 1507 return crypt_alloc_req_aead(cc, ctx); 1508 else 1509 return crypt_alloc_req_skcipher(cc, ctx); 1510 } 1511 1512 static void crypt_free_req_skcipher(struct crypt_config *cc, 1513 struct skcipher_request *req, struct bio *base_bio) 1514 { 1515 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1516 1517 if ((struct skcipher_request *)(io + 1) != req) 1518 mempool_free(req, &cc->req_pool); 1519 } 1520 1521 static void crypt_free_req_aead(struct crypt_config *cc, 1522 struct aead_request *req, struct bio *base_bio) 1523 { 1524 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1525 1526 if ((struct aead_request *)(io + 1) != req) 1527 mempool_free(req, &cc->req_pool); 1528 } 1529 1530 static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio) 1531 { 1532 if (crypt_integrity_aead(cc)) 1533 crypt_free_req_aead(cc, req, base_bio); 1534 else 1535 crypt_free_req_skcipher(cc, req, base_bio); 1536 } 1537 1538 /* 1539 * Encrypt / decrypt data from one bio to another one (can be the same one) 1540 */ 1541 static blk_status_t crypt_convert(struct crypt_config *cc, 1542 struct convert_context *ctx, bool atomic, bool reset_pending) 1543 { 1544 unsigned int tag_offset = 0; 1545 unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT; 1546 int r; 1547 1548 /* 1549 * if reset_pending is set we are dealing with the bio for the first time, 1550 * else we're continuing to work on the previous bio, so don't mess with 1551 * the cc_pending counter 1552 */ 1553 if (reset_pending) 1554 atomic_set(&ctx->cc_pending, 1); 1555 1556 while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) { 1557 1558 r = crypt_alloc_req(cc, ctx); 1559 if (r) { 1560 complete(&ctx->restart); 1561 return BLK_STS_DEV_RESOURCE; 1562 } 1563 1564 atomic_inc(&ctx->cc_pending); 1565 1566 if (crypt_integrity_aead(cc)) 1567 r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, tag_offset); 1568 else 1569 r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, tag_offset); 1570 1571 switch (r) { 1572 /* 1573 * The request was queued by a crypto driver 1574 * but the driver request queue is full, let's wait. 1575 */ 1576 case -EBUSY: 1577 if (in_interrupt()) { 1578 if (try_wait_for_completion(&ctx->restart)) { 1579 /* 1580 * we don't have to block to wait for completion, 1581 * so proceed 1582 */ 1583 } else { 1584 /* 1585 * we can't wait for completion without blocking 1586 * exit and continue processing in a workqueue 1587 */ 1588 ctx->r.req = NULL; 1589 ctx->cc_sector += sector_step; 1590 tag_offset++; 1591 return BLK_STS_DEV_RESOURCE; 1592 } 1593 } else { 1594 wait_for_completion(&ctx->restart); 1595 } 1596 reinit_completion(&ctx->restart); 1597 fallthrough; 1598 /* 1599 * The request is queued and processed asynchronously, 1600 * completion function kcryptd_async_done() will be called. 1601 */ 1602 case -EINPROGRESS: 1603 ctx->r.req = NULL; 1604 ctx->cc_sector += sector_step; 1605 tag_offset++; 1606 continue; 1607 /* 1608 * The request was already processed (synchronously). 1609 */ 1610 case 0: 1611 atomic_dec(&ctx->cc_pending); 1612 ctx->cc_sector += sector_step; 1613 tag_offset++; 1614 if (!atomic) 1615 cond_resched(); 1616 continue; 1617 /* 1618 * There was a data integrity error. 1619 */ 1620 case -EBADMSG: 1621 atomic_dec(&ctx->cc_pending); 1622 return BLK_STS_PROTECTION; 1623 /* 1624 * There was an error while processing the request. 1625 */ 1626 default: 1627 atomic_dec(&ctx->cc_pending); 1628 return BLK_STS_IOERR; 1629 } 1630 } 1631 1632 return 0; 1633 } 1634 1635 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone); 1636 1637 /* 1638 * Generate a new unfragmented bio with the given size 1639 * This should never violate the device limitations (but only because 1640 * max_segment_size is being constrained to PAGE_SIZE). 1641 * 1642 * This function may be called concurrently. If we allocate from the mempool 1643 * concurrently, there is a possibility of deadlock. For example, if we have 1644 * mempool of 256 pages, two processes, each wanting 256, pages allocate from 1645 * the mempool concurrently, it may deadlock in a situation where both processes 1646 * have allocated 128 pages and the mempool is exhausted. 1647 * 1648 * In order to avoid this scenario we allocate the pages under a mutex. 1649 * 1650 * In order to not degrade performance with excessive locking, we try 1651 * non-blocking allocations without a mutex first but on failure we fallback 1652 * to blocking allocations with a mutex. 1653 */ 1654 static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size) 1655 { 1656 struct crypt_config *cc = io->cc; 1657 struct bio *clone; 1658 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; 1659 gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM; 1660 unsigned i, len, remaining_size; 1661 struct page *page; 1662 1663 retry: 1664 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1665 mutex_lock(&cc->bio_alloc_lock); 1666 1667 clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, &cc->bs); 1668 if (!clone) 1669 goto out; 1670 1671 clone_init(io, clone); 1672 1673 remaining_size = size; 1674 1675 for (i = 0; i < nr_iovecs; i++) { 1676 page = mempool_alloc(&cc->page_pool, gfp_mask); 1677 if (!page) { 1678 crypt_free_buffer_pages(cc, clone); 1679 bio_put(clone); 1680 gfp_mask |= __GFP_DIRECT_RECLAIM; 1681 goto retry; 1682 } 1683 1684 len = (remaining_size > PAGE_SIZE) ? PAGE_SIZE : remaining_size; 1685 1686 bio_add_page(clone, page, len, 0); 1687 1688 remaining_size -= len; 1689 } 1690 1691 /* Allocate space for integrity tags */ 1692 if (dm_crypt_integrity_io_alloc(io, clone)) { 1693 crypt_free_buffer_pages(cc, clone); 1694 bio_put(clone); 1695 clone = NULL; 1696 } 1697 out: 1698 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1699 mutex_unlock(&cc->bio_alloc_lock); 1700 1701 return clone; 1702 } 1703 1704 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) 1705 { 1706 struct bio_vec *bv; 1707 struct bvec_iter_all iter_all; 1708 1709 bio_for_each_segment_all(bv, clone, iter_all) { 1710 BUG_ON(!bv->bv_page); 1711 mempool_free(bv->bv_page, &cc->page_pool); 1712 } 1713 } 1714 1715 static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc, 1716 struct bio *bio, sector_t sector) 1717 { 1718 io->cc = cc; 1719 io->base_bio = bio; 1720 io->sector = sector; 1721 io->error = 0; 1722 io->ctx.r.req = NULL; 1723 io->integrity_metadata = NULL; 1724 io->integrity_metadata_from_pool = false; 1725 atomic_set(&io->io_pending, 0); 1726 } 1727 1728 static void crypt_inc_pending(struct dm_crypt_io *io) 1729 { 1730 atomic_inc(&io->io_pending); 1731 } 1732 1733 static void kcryptd_io_bio_endio(struct work_struct *work) 1734 { 1735 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 1736 bio_endio(io->base_bio); 1737 } 1738 1739 /* 1740 * One of the bios was finished. Check for completion of 1741 * the whole request and correctly clean up the buffer. 1742 */ 1743 static void crypt_dec_pending(struct dm_crypt_io *io) 1744 { 1745 struct crypt_config *cc = io->cc; 1746 struct bio *base_bio = io->base_bio; 1747 blk_status_t error = io->error; 1748 1749 if (!atomic_dec_and_test(&io->io_pending)) 1750 return; 1751 1752 if (io->ctx.r.req) 1753 crypt_free_req(cc, io->ctx.r.req, base_bio); 1754 1755 if (unlikely(io->integrity_metadata_from_pool)) 1756 mempool_free(io->integrity_metadata, &io->cc->tag_pool); 1757 else 1758 kfree(io->integrity_metadata); 1759 1760 base_bio->bi_status = error; 1761 1762 /* 1763 * If we are running this function from our tasklet, 1764 * we can't call bio_endio() here, because it will call 1765 * clone_endio() from dm.c, which in turn will 1766 * free the current struct dm_crypt_io structure with 1767 * our tasklet. In this case we need to delay bio_endio() 1768 * execution to after the tasklet is done and dequeued. 1769 */ 1770 if (tasklet_trylock(&io->tasklet)) { 1771 tasklet_unlock(&io->tasklet); 1772 bio_endio(base_bio); 1773 return; 1774 } 1775 1776 INIT_WORK(&io->work, kcryptd_io_bio_endio); 1777 queue_work(cc->io_queue, &io->work); 1778 } 1779 1780 /* 1781 * kcryptd/kcryptd_io: 1782 * 1783 * Needed because it would be very unwise to do decryption in an 1784 * interrupt context. 1785 * 1786 * kcryptd performs the actual encryption or decryption. 1787 * 1788 * kcryptd_io performs the IO submission. 1789 * 1790 * They must be separated as otherwise the final stages could be 1791 * starved by new requests which can block in the first stages due 1792 * to memory allocation. 1793 * 1794 * The work is done per CPU global for all dm-crypt instances. 1795 * They should not depend on each other and do not block. 1796 */ 1797 static void crypt_endio(struct bio *clone) 1798 { 1799 struct dm_crypt_io *io = clone->bi_private; 1800 struct crypt_config *cc = io->cc; 1801 unsigned rw = bio_data_dir(clone); 1802 blk_status_t error; 1803 1804 /* 1805 * free the processed pages 1806 */ 1807 if (rw == WRITE) 1808 crypt_free_buffer_pages(cc, clone); 1809 1810 error = clone->bi_status; 1811 bio_put(clone); 1812 1813 if (rw == READ && !error) { 1814 kcryptd_queue_crypt(io); 1815 return; 1816 } 1817 1818 if (unlikely(error)) 1819 io->error = error; 1820 1821 crypt_dec_pending(io); 1822 } 1823 1824 static void clone_init(struct dm_crypt_io *io, struct bio *clone) 1825 { 1826 struct crypt_config *cc = io->cc; 1827 1828 clone->bi_private = io; 1829 clone->bi_end_io = crypt_endio; 1830 bio_set_dev(clone, cc->dev->bdev); 1831 clone->bi_opf = io->base_bio->bi_opf; 1832 } 1833 1834 static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp) 1835 { 1836 struct crypt_config *cc = io->cc; 1837 struct bio *clone; 1838 1839 /* 1840 * We need the original biovec array in order to decrypt 1841 * the whole bio data *afterwards* -- thanks to immutable 1842 * biovecs we don't need to worry about the block layer 1843 * modifying the biovec array; so leverage bio_clone_fast(). 1844 */ 1845 clone = bio_clone_fast(io->base_bio, gfp, &cc->bs); 1846 if (!clone) 1847 return 1; 1848 1849 crypt_inc_pending(io); 1850 1851 clone_init(io, clone); 1852 clone->bi_iter.bi_sector = cc->start + io->sector; 1853 1854 if (dm_crypt_integrity_io_alloc(io, clone)) { 1855 crypt_dec_pending(io); 1856 bio_put(clone); 1857 return 1; 1858 } 1859 1860 submit_bio_noacct(clone); 1861 return 0; 1862 } 1863 1864 static void kcryptd_io_read_work(struct work_struct *work) 1865 { 1866 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 1867 1868 crypt_inc_pending(io); 1869 if (kcryptd_io_read(io, GFP_NOIO)) 1870 io->error = BLK_STS_RESOURCE; 1871 crypt_dec_pending(io); 1872 } 1873 1874 static void kcryptd_queue_read(struct dm_crypt_io *io) 1875 { 1876 struct crypt_config *cc = io->cc; 1877 1878 INIT_WORK(&io->work, kcryptd_io_read_work); 1879 queue_work(cc->io_queue, &io->work); 1880 } 1881 1882 static void kcryptd_io_write(struct dm_crypt_io *io) 1883 { 1884 struct bio *clone = io->ctx.bio_out; 1885 1886 submit_bio_noacct(clone); 1887 } 1888 1889 #define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node) 1890 1891 static int dmcrypt_write(void *data) 1892 { 1893 struct crypt_config *cc = data; 1894 struct dm_crypt_io *io; 1895 1896 while (1) { 1897 struct rb_root write_tree; 1898 struct blk_plug plug; 1899 1900 spin_lock_irq(&cc->write_thread_lock); 1901 continue_locked: 1902 1903 if (!RB_EMPTY_ROOT(&cc->write_tree)) 1904 goto pop_from_list; 1905 1906 set_current_state(TASK_INTERRUPTIBLE); 1907 1908 spin_unlock_irq(&cc->write_thread_lock); 1909 1910 if (unlikely(kthread_should_stop())) { 1911 set_current_state(TASK_RUNNING); 1912 break; 1913 } 1914 1915 schedule(); 1916 1917 set_current_state(TASK_RUNNING); 1918 spin_lock_irq(&cc->write_thread_lock); 1919 goto continue_locked; 1920 1921 pop_from_list: 1922 write_tree = cc->write_tree; 1923 cc->write_tree = RB_ROOT; 1924 spin_unlock_irq(&cc->write_thread_lock); 1925 1926 BUG_ON(rb_parent(write_tree.rb_node)); 1927 1928 /* 1929 * Note: we cannot walk the tree here with rb_next because 1930 * the structures may be freed when kcryptd_io_write is called. 1931 */ 1932 blk_start_plug(&plug); 1933 do { 1934 io = crypt_io_from_node(rb_first(&write_tree)); 1935 rb_erase(&io->rb_node, &write_tree); 1936 kcryptd_io_write(io); 1937 } while (!RB_EMPTY_ROOT(&write_tree)); 1938 blk_finish_plug(&plug); 1939 } 1940 return 0; 1941 } 1942 1943 static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async) 1944 { 1945 struct bio *clone = io->ctx.bio_out; 1946 struct crypt_config *cc = io->cc; 1947 unsigned long flags; 1948 sector_t sector; 1949 struct rb_node **rbp, *parent; 1950 1951 if (unlikely(io->error)) { 1952 crypt_free_buffer_pages(cc, clone); 1953 bio_put(clone); 1954 crypt_dec_pending(io); 1955 return; 1956 } 1957 1958 /* crypt_convert should have filled the clone bio */ 1959 BUG_ON(io->ctx.iter_out.bi_size); 1960 1961 clone->bi_iter.bi_sector = cc->start + io->sector; 1962 1963 if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) || 1964 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) { 1965 submit_bio_noacct(clone); 1966 return; 1967 } 1968 1969 spin_lock_irqsave(&cc->write_thread_lock, flags); 1970 if (RB_EMPTY_ROOT(&cc->write_tree)) 1971 wake_up_process(cc->write_thread); 1972 rbp = &cc->write_tree.rb_node; 1973 parent = NULL; 1974 sector = io->sector; 1975 while (*rbp) { 1976 parent = *rbp; 1977 if (sector < crypt_io_from_node(parent)->sector) 1978 rbp = &(*rbp)->rb_left; 1979 else 1980 rbp = &(*rbp)->rb_right; 1981 } 1982 rb_link_node(&io->rb_node, parent, rbp); 1983 rb_insert_color(&io->rb_node, &cc->write_tree); 1984 spin_unlock_irqrestore(&cc->write_thread_lock, flags); 1985 } 1986 1987 static bool kcryptd_crypt_write_inline(struct crypt_config *cc, 1988 struct convert_context *ctx) 1989 1990 { 1991 if (!test_bit(DM_CRYPT_WRITE_INLINE, &cc->flags)) 1992 return false; 1993 1994 /* 1995 * Note: zone append writes (REQ_OP_ZONE_APPEND) do not have ordering 1996 * constraints so they do not need to be issued inline by 1997 * kcryptd_crypt_write_convert(). 1998 */ 1999 switch (bio_op(ctx->bio_in)) { 2000 case REQ_OP_WRITE: 2001 case REQ_OP_WRITE_SAME: 2002 case REQ_OP_WRITE_ZEROES: 2003 return true; 2004 default: 2005 return false; 2006 } 2007 } 2008 2009 static void kcryptd_crypt_write_continue(struct work_struct *work) 2010 { 2011 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2012 struct crypt_config *cc = io->cc; 2013 struct convert_context *ctx = &io->ctx; 2014 int crypt_finished; 2015 sector_t sector = io->sector; 2016 blk_status_t r; 2017 2018 wait_for_completion(&ctx->restart); 2019 reinit_completion(&ctx->restart); 2020 2021 r = crypt_convert(cc, &io->ctx, true, false); 2022 if (r) 2023 io->error = r; 2024 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2025 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2026 /* Wait for completion signaled by kcryptd_async_done() */ 2027 wait_for_completion(&ctx->restart); 2028 crypt_finished = 1; 2029 } 2030 2031 /* Encryption was already finished, submit io now */ 2032 if (crypt_finished) { 2033 kcryptd_crypt_write_io_submit(io, 0); 2034 io->sector = sector; 2035 } 2036 2037 crypt_dec_pending(io); 2038 } 2039 2040 static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) 2041 { 2042 struct crypt_config *cc = io->cc; 2043 struct convert_context *ctx = &io->ctx; 2044 struct bio *clone; 2045 int crypt_finished; 2046 sector_t sector = io->sector; 2047 blk_status_t r; 2048 2049 /* 2050 * Prevent io from disappearing until this function completes. 2051 */ 2052 crypt_inc_pending(io); 2053 crypt_convert_init(cc, ctx, NULL, io->base_bio, sector); 2054 2055 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size); 2056 if (unlikely(!clone)) { 2057 io->error = BLK_STS_IOERR; 2058 goto dec; 2059 } 2060 2061 io->ctx.bio_out = clone; 2062 io->ctx.iter_out = clone->bi_iter; 2063 2064 sector += bio_sectors(clone); 2065 2066 crypt_inc_pending(io); 2067 r = crypt_convert(cc, ctx, 2068 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags), true); 2069 /* 2070 * Crypto API backlogged the request, because its queue was full 2071 * and we're in softirq context, so continue from a workqueue 2072 * (TODO: is it actually possible to be in softirq in the write path?) 2073 */ 2074 if (r == BLK_STS_DEV_RESOURCE) { 2075 INIT_WORK(&io->work, kcryptd_crypt_write_continue); 2076 queue_work(cc->crypt_queue, &io->work); 2077 return; 2078 } 2079 if (r) 2080 io->error = r; 2081 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2082 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2083 /* Wait for completion signaled by kcryptd_async_done() */ 2084 wait_for_completion(&ctx->restart); 2085 crypt_finished = 1; 2086 } 2087 2088 /* Encryption was already finished, submit io now */ 2089 if (crypt_finished) { 2090 kcryptd_crypt_write_io_submit(io, 0); 2091 io->sector = sector; 2092 } 2093 2094 dec: 2095 crypt_dec_pending(io); 2096 } 2097 2098 static void kcryptd_crypt_read_done(struct dm_crypt_io *io) 2099 { 2100 crypt_dec_pending(io); 2101 } 2102 2103 static void kcryptd_crypt_read_continue(struct work_struct *work) 2104 { 2105 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2106 struct crypt_config *cc = io->cc; 2107 blk_status_t r; 2108 2109 wait_for_completion(&io->ctx.restart); 2110 reinit_completion(&io->ctx.restart); 2111 2112 r = crypt_convert(cc, &io->ctx, true, false); 2113 if (r) 2114 io->error = r; 2115 2116 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2117 kcryptd_crypt_read_done(io); 2118 2119 crypt_dec_pending(io); 2120 } 2121 2122 static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) 2123 { 2124 struct crypt_config *cc = io->cc; 2125 blk_status_t r; 2126 2127 crypt_inc_pending(io); 2128 2129 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, 2130 io->sector); 2131 2132 r = crypt_convert(cc, &io->ctx, 2133 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true); 2134 /* 2135 * Crypto API backlogged the request, because its queue was full 2136 * and we're in softirq context, so continue from a workqueue 2137 */ 2138 if (r == BLK_STS_DEV_RESOURCE) { 2139 INIT_WORK(&io->work, kcryptd_crypt_read_continue); 2140 queue_work(cc->crypt_queue, &io->work); 2141 return; 2142 } 2143 if (r) 2144 io->error = r; 2145 2146 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2147 kcryptd_crypt_read_done(io); 2148 2149 crypt_dec_pending(io); 2150 } 2151 2152 static void kcryptd_async_done(struct crypto_async_request *async_req, 2153 int error) 2154 { 2155 struct dm_crypt_request *dmreq = async_req->data; 2156 struct convert_context *ctx = dmreq->ctx; 2157 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 2158 struct crypt_config *cc = io->cc; 2159 2160 /* 2161 * A request from crypto driver backlog is going to be processed now, 2162 * finish the completion and continue in crypt_convert(). 2163 * (Callback will be called for the second time for this request.) 2164 */ 2165 if (error == -EINPROGRESS) { 2166 complete(&ctx->restart); 2167 return; 2168 } 2169 2170 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post) 2171 error = cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq); 2172 2173 if (error == -EBADMSG) { 2174 char b[BDEVNAME_SIZE]; 2175 DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu", bio_devname(ctx->bio_in, b), 2176 (unsigned long long)le64_to_cpu(*org_sector_of_dmreq(cc, dmreq))); 2177 io->error = BLK_STS_PROTECTION; 2178 } else if (error < 0) 2179 io->error = BLK_STS_IOERR; 2180 2181 crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio); 2182 2183 if (!atomic_dec_and_test(&ctx->cc_pending)) 2184 return; 2185 2186 /* 2187 * The request is fully completed: for inline writes, let 2188 * kcryptd_crypt_write_convert() do the IO submission. 2189 */ 2190 if (bio_data_dir(io->base_bio) == READ) { 2191 kcryptd_crypt_read_done(io); 2192 return; 2193 } 2194 2195 if (kcryptd_crypt_write_inline(cc, ctx)) { 2196 complete(&ctx->restart); 2197 return; 2198 } 2199 2200 kcryptd_crypt_write_io_submit(io, 1); 2201 } 2202 2203 static void kcryptd_crypt(struct work_struct *work) 2204 { 2205 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2206 2207 if (bio_data_dir(io->base_bio) == READ) 2208 kcryptd_crypt_read_convert(io); 2209 else 2210 kcryptd_crypt_write_convert(io); 2211 } 2212 2213 static void kcryptd_crypt_tasklet(unsigned long work) 2214 { 2215 kcryptd_crypt((struct work_struct *)work); 2216 } 2217 2218 static void kcryptd_queue_crypt(struct dm_crypt_io *io) 2219 { 2220 struct crypt_config *cc = io->cc; 2221 2222 if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) || 2223 (bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) { 2224 /* 2225 * in_irq(): Crypto API's skcipher_walk_first() refuses to work in hard IRQ context. 2226 * irqs_disabled(): the kernel may run some IO completion from the idle thread, but 2227 * it is being executed with irqs disabled. 2228 */ 2229 if (in_irq() || irqs_disabled()) { 2230 tasklet_init(&io->tasklet, kcryptd_crypt_tasklet, (unsigned long)&io->work); 2231 tasklet_schedule(&io->tasklet); 2232 return; 2233 } 2234 2235 kcryptd_crypt(&io->work); 2236 return; 2237 } 2238 2239 INIT_WORK(&io->work, kcryptd_crypt); 2240 queue_work(cc->crypt_queue, &io->work); 2241 } 2242 2243 static void crypt_free_tfms_aead(struct crypt_config *cc) 2244 { 2245 if (!cc->cipher_tfm.tfms_aead) 2246 return; 2247 2248 if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2249 crypto_free_aead(cc->cipher_tfm.tfms_aead[0]); 2250 cc->cipher_tfm.tfms_aead[0] = NULL; 2251 } 2252 2253 kfree(cc->cipher_tfm.tfms_aead); 2254 cc->cipher_tfm.tfms_aead = NULL; 2255 } 2256 2257 static void crypt_free_tfms_skcipher(struct crypt_config *cc) 2258 { 2259 unsigned i; 2260 2261 if (!cc->cipher_tfm.tfms) 2262 return; 2263 2264 for (i = 0; i < cc->tfms_count; i++) 2265 if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) { 2266 crypto_free_skcipher(cc->cipher_tfm.tfms[i]); 2267 cc->cipher_tfm.tfms[i] = NULL; 2268 } 2269 2270 kfree(cc->cipher_tfm.tfms); 2271 cc->cipher_tfm.tfms = NULL; 2272 } 2273 2274 static void crypt_free_tfms(struct crypt_config *cc) 2275 { 2276 if (crypt_integrity_aead(cc)) 2277 crypt_free_tfms_aead(cc); 2278 else 2279 crypt_free_tfms_skcipher(cc); 2280 } 2281 2282 static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode) 2283 { 2284 unsigned i; 2285 int err; 2286 2287 cc->cipher_tfm.tfms = kcalloc(cc->tfms_count, 2288 sizeof(struct crypto_skcipher *), 2289 GFP_KERNEL); 2290 if (!cc->cipher_tfm.tfms) 2291 return -ENOMEM; 2292 2293 for (i = 0; i < cc->tfms_count; i++) { 2294 cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0, 2295 CRYPTO_ALG_ALLOCATES_MEMORY); 2296 if (IS_ERR(cc->cipher_tfm.tfms[i])) { 2297 err = PTR_ERR(cc->cipher_tfm.tfms[i]); 2298 crypt_free_tfms(cc); 2299 return err; 2300 } 2301 } 2302 2303 /* 2304 * dm-crypt performance can vary greatly depending on which crypto 2305 * algorithm implementation is used. Help people debug performance 2306 * problems by logging the ->cra_driver_name. 2307 */ 2308 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2309 crypto_skcipher_alg(any_tfm(cc))->base.cra_driver_name); 2310 return 0; 2311 } 2312 2313 static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode) 2314 { 2315 int err; 2316 2317 cc->cipher_tfm.tfms = kmalloc(sizeof(struct crypto_aead *), GFP_KERNEL); 2318 if (!cc->cipher_tfm.tfms) 2319 return -ENOMEM; 2320 2321 cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0, 2322 CRYPTO_ALG_ALLOCATES_MEMORY); 2323 if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2324 err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]); 2325 crypt_free_tfms(cc); 2326 return err; 2327 } 2328 2329 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2330 crypto_aead_alg(any_tfm_aead(cc))->base.cra_driver_name); 2331 return 0; 2332 } 2333 2334 static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode) 2335 { 2336 if (crypt_integrity_aead(cc)) 2337 return crypt_alloc_tfms_aead(cc, ciphermode); 2338 else 2339 return crypt_alloc_tfms_skcipher(cc, ciphermode); 2340 } 2341 2342 static unsigned crypt_subkey_size(struct crypt_config *cc) 2343 { 2344 return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count); 2345 } 2346 2347 static unsigned crypt_authenckey_size(struct crypt_config *cc) 2348 { 2349 return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param)); 2350 } 2351 2352 /* 2353 * If AEAD is composed like authenc(hmac(sha256),xts(aes)), 2354 * the key must be for some reason in special format. 2355 * This funcion converts cc->key to this special format. 2356 */ 2357 static void crypt_copy_authenckey(char *p, const void *key, 2358 unsigned enckeylen, unsigned authkeylen) 2359 { 2360 struct crypto_authenc_key_param *param; 2361 struct rtattr *rta; 2362 2363 rta = (struct rtattr *)p; 2364 param = RTA_DATA(rta); 2365 param->enckeylen = cpu_to_be32(enckeylen); 2366 rta->rta_len = RTA_LENGTH(sizeof(*param)); 2367 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; 2368 p += RTA_SPACE(sizeof(*param)); 2369 memcpy(p, key + enckeylen, authkeylen); 2370 p += authkeylen; 2371 memcpy(p, key, enckeylen); 2372 } 2373 2374 static int crypt_setkey(struct crypt_config *cc) 2375 { 2376 unsigned subkey_size; 2377 int err = 0, i, r; 2378 2379 /* Ignore extra keys (which are used for IV etc) */ 2380 subkey_size = crypt_subkey_size(cc); 2381 2382 if (crypt_integrity_hmac(cc)) { 2383 if (subkey_size < cc->key_mac_size) 2384 return -EINVAL; 2385 2386 crypt_copy_authenckey(cc->authenc_key, cc->key, 2387 subkey_size - cc->key_mac_size, 2388 cc->key_mac_size); 2389 } 2390 2391 for (i = 0; i < cc->tfms_count; i++) { 2392 if (crypt_integrity_hmac(cc)) 2393 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2394 cc->authenc_key, crypt_authenckey_size(cc)); 2395 else if (crypt_integrity_aead(cc)) 2396 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2397 cc->key + (i * subkey_size), 2398 subkey_size); 2399 else 2400 r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i], 2401 cc->key + (i * subkey_size), 2402 subkey_size); 2403 if (r) 2404 err = r; 2405 } 2406 2407 if (crypt_integrity_hmac(cc)) 2408 memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc)); 2409 2410 return err; 2411 } 2412 2413 #ifdef CONFIG_KEYS 2414 2415 static bool contains_whitespace(const char *str) 2416 { 2417 while (*str) 2418 if (isspace(*str++)) 2419 return true; 2420 return false; 2421 } 2422 2423 static int set_key_user(struct crypt_config *cc, struct key *key) 2424 { 2425 const struct user_key_payload *ukp; 2426 2427 ukp = user_key_payload_locked(key); 2428 if (!ukp) 2429 return -EKEYREVOKED; 2430 2431 if (cc->key_size != ukp->datalen) 2432 return -EINVAL; 2433 2434 memcpy(cc->key, ukp->data, cc->key_size); 2435 2436 return 0; 2437 } 2438 2439 #if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE) 2440 static int set_key_encrypted(struct crypt_config *cc, struct key *key) 2441 { 2442 const struct encrypted_key_payload *ekp; 2443 2444 ekp = key->payload.data[0]; 2445 if (!ekp) 2446 return -EKEYREVOKED; 2447 2448 if (cc->key_size != ekp->decrypted_datalen) 2449 return -EINVAL; 2450 2451 memcpy(cc->key, ekp->decrypted_data, cc->key_size); 2452 2453 return 0; 2454 } 2455 #endif /* CONFIG_ENCRYPTED_KEYS */ 2456 2457 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2458 { 2459 char *new_key_string, *key_desc; 2460 int ret; 2461 struct key_type *type; 2462 struct key *key; 2463 int (*set_key)(struct crypt_config *cc, struct key *key); 2464 2465 /* 2466 * Reject key_string with whitespace. dm core currently lacks code for 2467 * proper whitespace escaping in arguments on DM_TABLE_STATUS path. 2468 */ 2469 if (contains_whitespace(key_string)) { 2470 DMERR("whitespace chars not allowed in key string"); 2471 return -EINVAL; 2472 } 2473 2474 /* look for next ':' separating key_type from key_description */ 2475 key_desc = strpbrk(key_string, ":"); 2476 if (!key_desc || key_desc == key_string || !strlen(key_desc + 1)) 2477 return -EINVAL; 2478 2479 if (!strncmp(key_string, "logon:", key_desc - key_string + 1)) { 2480 type = &key_type_logon; 2481 set_key = set_key_user; 2482 } else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) { 2483 type = &key_type_user; 2484 set_key = set_key_user; 2485 #if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE) 2486 } else if (!strncmp(key_string, "encrypted:", key_desc - key_string + 1)) { 2487 type = &key_type_encrypted; 2488 set_key = set_key_encrypted; 2489 #endif 2490 } else { 2491 return -EINVAL; 2492 } 2493 2494 new_key_string = kstrdup(key_string, GFP_KERNEL); 2495 if (!new_key_string) 2496 return -ENOMEM; 2497 2498 key = request_key(type, key_desc + 1, NULL); 2499 if (IS_ERR(key)) { 2500 kfree_sensitive(new_key_string); 2501 return PTR_ERR(key); 2502 } 2503 2504 down_read(&key->sem); 2505 2506 ret = set_key(cc, key); 2507 if (ret < 0) { 2508 up_read(&key->sem); 2509 key_put(key); 2510 kfree_sensitive(new_key_string); 2511 return ret; 2512 } 2513 2514 up_read(&key->sem); 2515 key_put(key); 2516 2517 /* clear the flag since following operations may invalidate previously valid key */ 2518 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2519 2520 ret = crypt_setkey(cc); 2521 2522 if (!ret) { 2523 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2524 kfree_sensitive(cc->key_string); 2525 cc->key_string = new_key_string; 2526 } else 2527 kfree_sensitive(new_key_string); 2528 2529 return ret; 2530 } 2531 2532 static int get_key_size(char **key_string) 2533 { 2534 char *colon, dummy; 2535 int ret; 2536 2537 if (*key_string[0] != ':') 2538 return strlen(*key_string) >> 1; 2539 2540 /* look for next ':' in key string */ 2541 colon = strpbrk(*key_string + 1, ":"); 2542 if (!colon) 2543 return -EINVAL; 2544 2545 if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':') 2546 return -EINVAL; 2547 2548 *key_string = colon; 2549 2550 /* remaining key string should be :<logon|user>:<key_desc> */ 2551 2552 return ret; 2553 } 2554 2555 #else 2556 2557 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2558 { 2559 return -EINVAL; 2560 } 2561 2562 static int get_key_size(char **key_string) 2563 { 2564 return (*key_string[0] == ':') ? -EINVAL : strlen(*key_string) >> 1; 2565 } 2566 2567 #endif /* CONFIG_KEYS */ 2568 2569 static int crypt_set_key(struct crypt_config *cc, char *key) 2570 { 2571 int r = -EINVAL; 2572 int key_string_len = strlen(key); 2573 2574 /* Hyphen (which gives a key_size of zero) means there is no key. */ 2575 if (!cc->key_size && strcmp(key, "-")) 2576 goto out; 2577 2578 /* ':' means the key is in kernel keyring, short-circuit normal key processing */ 2579 if (key[0] == ':') { 2580 r = crypt_set_keyring_key(cc, key + 1); 2581 goto out; 2582 } 2583 2584 /* clear the flag since following operations may invalidate previously valid key */ 2585 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2586 2587 /* wipe references to any kernel keyring key */ 2588 kfree_sensitive(cc->key_string); 2589 cc->key_string = NULL; 2590 2591 /* Decode key from its hex representation. */ 2592 if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0) 2593 goto out; 2594 2595 r = crypt_setkey(cc); 2596 if (!r) 2597 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2598 2599 out: 2600 /* Hex key string not needed after here, so wipe it. */ 2601 memset(key, '0', key_string_len); 2602 2603 return r; 2604 } 2605 2606 static int crypt_wipe_key(struct crypt_config *cc) 2607 { 2608 int r; 2609 2610 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2611 get_random_bytes(&cc->key, cc->key_size); 2612 2613 /* Wipe IV private keys */ 2614 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) { 2615 r = cc->iv_gen_ops->wipe(cc); 2616 if (r) 2617 return r; 2618 } 2619 2620 kfree_sensitive(cc->key_string); 2621 cc->key_string = NULL; 2622 r = crypt_setkey(cc); 2623 memset(&cc->key, 0, cc->key_size * sizeof(u8)); 2624 2625 return r; 2626 } 2627 2628 static void crypt_calculate_pages_per_client(void) 2629 { 2630 unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100; 2631 2632 if (!dm_crypt_clients_n) 2633 return; 2634 2635 pages /= dm_crypt_clients_n; 2636 if (pages < DM_CRYPT_MIN_PAGES_PER_CLIENT) 2637 pages = DM_CRYPT_MIN_PAGES_PER_CLIENT; 2638 dm_crypt_pages_per_client = pages; 2639 } 2640 2641 static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data) 2642 { 2643 struct crypt_config *cc = pool_data; 2644 struct page *page; 2645 2646 if (unlikely(percpu_counter_compare(&cc->n_allocated_pages, dm_crypt_pages_per_client) >= 0) && 2647 likely(gfp_mask & __GFP_NORETRY)) 2648 return NULL; 2649 2650 page = alloc_page(gfp_mask); 2651 if (likely(page != NULL)) 2652 percpu_counter_add(&cc->n_allocated_pages, 1); 2653 2654 return page; 2655 } 2656 2657 static void crypt_page_free(void *page, void *pool_data) 2658 { 2659 struct crypt_config *cc = pool_data; 2660 2661 __free_page(page); 2662 percpu_counter_sub(&cc->n_allocated_pages, 1); 2663 } 2664 2665 static void crypt_dtr(struct dm_target *ti) 2666 { 2667 struct crypt_config *cc = ti->private; 2668 2669 ti->private = NULL; 2670 2671 if (!cc) 2672 return; 2673 2674 if (cc->write_thread) 2675 kthread_stop(cc->write_thread); 2676 2677 if (cc->io_queue) 2678 destroy_workqueue(cc->io_queue); 2679 if (cc->crypt_queue) 2680 destroy_workqueue(cc->crypt_queue); 2681 2682 crypt_free_tfms(cc); 2683 2684 bioset_exit(&cc->bs); 2685 2686 mempool_exit(&cc->page_pool); 2687 mempool_exit(&cc->req_pool); 2688 mempool_exit(&cc->tag_pool); 2689 2690 WARN_ON(percpu_counter_sum(&cc->n_allocated_pages) != 0); 2691 percpu_counter_destroy(&cc->n_allocated_pages); 2692 2693 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) 2694 cc->iv_gen_ops->dtr(cc); 2695 2696 if (cc->dev) 2697 dm_put_device(ti, cc->dev); 2698 2699 kfree_sensitive(cc->cipher_string); 2700 kfree_sensitive(cc->key_string); 2701 kfree_sensitive(cc->cipher_auth); 2702 kfree_sensitive(cc->authenc_key); 2703 2704 mutex_destroy(&cc->bio_alloc_lock); 2705 2706 /* Must zero key material before freeing */ 2707 kfree_sensitive(cc); 2708 2709 spin_lock(&dm_crypt_clients_lock); 2710 WARN_ON(!dm_crypt_clients_n); 2711 dm_crypt_clients_n--; 2712 crypt_calculate_pages_per_client(); 2713 spin_unlock(&dm_crypt_clients_lock); 2714 } 2715 2716 static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode) 2717 { 2718 struct crypt_config *cc = ti->private; 2719 2720 if (crypt_integrity_aead(cc)) 2721 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2722 else 2723 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2724 2725 if (cc->iv_size) 2726 /* at least a 64 bit sector number should fit in our buffer */ 2727 cc->iv_size = max(cc->iv_size, 2728 (unsigned int)(sizeof(u64) / sizeof(u8))); 2729 else if (ivmode) { 2730 DMWARN("Selected cipher does not support IVs"); 2731 ivmode = NULL; 2732 } 2733 2734 /* Choose ivmode, see comments at iv code. */ 2735 if (ivmode == NULL) 2736 cc->iv_gen_ops = NULL; 2737 else if (strcmp(ivmode, "plain") == 0) 2738 cc->iv_gen_ops = &crypt_iv_plain_ops; 2739 else if (strcmp(ivmode, "plain64") == 0) 2740 cc->iv_gen_ops = &crypt_iv_plain64_ops; 2741 else if (strcmp(ivmode, "plain64be") == 0) 2742 cc->iv_gen_ops = &crypt_iv_plain64be_ops; 2743 else if (strcmp(ivmode, "essiv") == 0) 2744 cc->iv_gen_ops = &crypt_iv_essiv_ops; 2745 else if (strcmp(ivmode, "benbi") == 0) 2746 cc->iv_gen_ops = &crypt_iv_benbi_ops; 2747 else if (strcmp(ivmode, "null") == 0) 2748 cc->iv_gen_ops = &crypt_iv_null_ops; 2749 else if (strcmp(ivmode, "eboiv") == 0) 2750 cc->iv_gen_ops = &crypt_iv_eboiv_ops; 2751 else if (strcmp(ivmode, "elephant") == 0) { 2752 cc->iv_gen_ops = &crypt_iv_elephant_ops; 2753 cc->key_parts = 2; 2754 cc->key_extra_size = cc->key_size / 2; 2755 if (cc->key_extra_size > ELEPHANT_MAX_KEY_SIZE) 2756 return -EINVAL; 2757 set_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags); 2758 } else if (strcmp(ivmode, "lmk") == 0) { 2759 cc->iv_gen_ops = &crypt_iv_lmk_ops; 2760 /* 2761 * Version 2 and 3 is recognised according 2762 * to length of provided multi-key string. 2763 * If present (version 3), last key is used as IV seed. 2764 * All keys (including IV seed) are always the same size. 2765 */ 2766 if (cc->key_size % cc->key_parts) { 2767 cc->key_parts++; 2768 cc->key_extra_size = cc->key_size / cc->key_parts; 2769 } 2770 } else if (strcmp(ivmode, "tcw") == 0) { 2771 cc->iv_gen_ops = &crypt_iv_tcw_ops; 2772 cc->key_parts += 2; /* IV + whitening */ 2773 cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE; 2774 } else if (strcmp(ivmode, "random") == 0) { 2775 cc->iv_gen_ops = &crypt_iv_random_ops; 2776 /* Need storage space in integrity fields. */ 2777 cc->integrity_iv_size = cc->iv_size; 2778 } else { 2779 ti->error = "Invalid IV mode"; 2780 return -EINVAL; 2781 } 2782 2783 return 0; 2784 } 2785 2786 /* 2787 * Workaround to parse HMAC algorithm from AEAD crypto API spec. 2788 * The HMAC is needed to calculate tag size (HMAC digest size). 2789 * This should be probably done by crypto-api calls (once available...) 2790 */ 2791 static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api) 2792 { 2793 char *start, *end, *mac_alg = NULL; 2794 struct crypto_ahash *mac; 2795 2796 if (!strstarts(cipher_api, "authenc(")) 2797 return 0; 2798 2799 start = strchr(cipher_api, '('); 2800 end = strchr(cipher_api, ','); 2801 if (!start || !end || ++start > end) 2802 return -EINVAL; 2803 2804 mac_alg = kzalloc(end - start + 1, GFP_KERNEL); 2805 if (!mac_alg) 2806 return -ENOMEM; 2807 strncpy(mac_alg, start, end - start); 2808 2809 mac = crypto_alloc_ahash(mac_alg, 0, CRYPTO_ALG_ALLOCATES_MEMORY); 2810 kfree(mac_alg); 2811 2812 if (IS_ERR(mac)) 2813 return PTR_ERR(mac); 2814 2815 cc->key_mac_size = crypto_ahash_digestsize(mac); 2816 crypto_free_ahash(mac); 2817 2818 cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL); 2819 if (!cc->authenc_key) 2820 return -ENOMEM; 2821 2822 return 0; 2823 } 2824 2825 static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key, 2826 char **ivmode, char **ivopts) 2827 { 2828 struct crypt_config *cc = ti->private; 2829 char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME]; 2830 int ret = -EINVAL; 2831 2832 cc->tfms_count = 1; 2833 2834 /* 2835 * New format (capi: prefix) 2836 * capi:cipher_api_spec-iv:ivopts 2837 */ 2838 tmp = &cipher_in[strlen("capi:")]; 2839 2840 /* Separate IV options if present, it can contain another '-' in hash name */ 2841 *ivopts = strrchr(tmp, ':'); 2842 if (*ivopts) { 2843 **ivopts = '\0'; 2844 (*ivopts)++; 2845 } 2846 /* Parse IV mode */ 2847 *ivmode = strrchr(tmp, '-'); 2848 if (*ivmode) { 2849 **ivmode = '\0'; 2850 (*ivmode)++; 2851 } 2852 /* The rest is crypto API spec */ 2853 cipher_api = tmp; 2854 2855 /* Alloc AEAD, can be used only in new format. */ 2856 if (crypt_integrity_aead(cc)) { 2857 ret = crypt_ctr_auth_cipher(cc, cipher_api); 2858 if (ret < 0) { 2859 ti->error = "Invalid AEAD cipher spec"; 2860 return -ENOMEM; 2861 } 2862 } 2863 2864 if (*ivmode && !strcmp(*ivmode, "lmk")) 2865 cc->tfms_count = 64; 2866 2867 if (*ivmode && !strcmp(*ivmode, "essiv")) { 2868 if (!*ivopts) { 2869 ti->error = "Digest algorithm missing for ESSIV mode"; 2870 return -EINVAL; 2871 } 2872 ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)", 2873 cipher_api, *ivopts); 2874 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 2875 ti->error = "Cannot allocate cipher string"; 2876 return -ENOMEM; 2877 } 2878 cipher_api = buf; 2879 } 2880 2881 cc->key_parts = cc->tfms_count; 2882 2883 /* Allocate cipher */ 2884 ret = crypt_alloc_tfms(cc, cipher_api); 2885 if (ret < 0) { 2886 ti->error = "Error allocating crypto tfm"; 2887 return ret; 2888 } 2889 2890 if (crypt_integrity_aead(cc)) 2891 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2892 else 2893 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2894 2895 return 0; 2896 } 2897 2898 static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key, 2899 char **ivmode, char **ivopts) 2900 { 2901 struct crypt_config *cc = ti->private; 2902 char *tmp, *cipher, *chainmode, *keycount; 2903 char *cipher_api = NULL; 2904 int ret = -EINVAL; 2905 char dummy; 2906 2907 if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) { 2908 ti->error = "Bad cipher specification"; 2909 return -EINVAL; 2910 } 2911 2912 /* 2913 * Legacy dm-crypt cipher specification 2914 * cipher[:keycount]-mode-iv:ivopts 2915 */ 2916 tmp = cipher_in; 2917 keycount = strsep(&tmp, "-"); 2918 cipher = strsep(&keycount, ":"); 2919 2920 if (!keycount) 2921 cc->tfms_count = 1; 2922 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 || 2923 !is_power_of_2(cc->tfms_count)) { 2924 ti->error = "Bad cipher key count specification"; 2925 return -EINVAL; 2926 } 2927 cc->key_parts = cc->tfms_count; 2928 2929 chainmode = strsep(&tmp, "-"); 2930 *ivmode = strsep(&tmp, ":"); 2931 *ivopts = tmp; 2932 2933 /* 2934 * For compatibility with the original dm-crypt mapping format, if 2935 * only the cipher name is supplied, use cbc-plain. 2936 */ 2937 if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) { 2938 chainmode = "cbc"; 2939 *ivmode = "plain"; 2940 } 2941 2942 if (strcmp(chainmode, "ecb") && !*ivmode) { 2943 ti->error = "IV mechanism required"; 2944 return -EINVAL; 2945 } 2946 2947 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL); 2948 if (!cipher_api) 2949 goto bad_mem; 2950 2951 if (*ivmode && !strcmp(*ivmode, "essiv")) { 2952 if (!*ivopts) { 2953 ti->error = "Digest algorithm missing for ESSIV mode"; 2954 kfree(cipher_api); 2955 return -EINVAL; 2956 } 2957 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 2958 "essiv(%s(%s),%s)", chainmode, cipher, *ivopts); 2959 } else { 2960 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 2961 "%s(%s)", chainmode, cipher); 2962 } 2963 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 2964 kfree(cipher_api); 2965 goto bad_mem; 2966 } 2967 2968 /* Allocate cipher */ 2969 ret = crypt_alloc_tfms(cc, cipher_api); 2970 if (ret < 0) { 2971 ti->error = "Error allocating crypto tfm"; 2972 kfree(cipher_api); 2973 return ret; 2974 } 2975 kfree(cipher_api); 2976 2977 return 0; 2978 bad_mem: 2979 ti->error = "Cannot allocate cipher strings"; 2980 return -ENOMEM; 2981 } 2982 2983 static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key) 2984 { 2985 struct crypt_config *cc = ti->private; 2986 char *ivmode = NULL, *ivopts = NULL; 2987 int ret; 2988 2989 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL); 2990 if (!cc->cipher_string) { 2991 ti->error = "Cannot allocate cipher strings"; 2992 return -ENOMEM; 2993 } 2994 2995 if (strstarts(cipher_in, "capi:")) 2996 ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts); 2997 else 2998 ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts); 2999 if (ret) 3000 return ret; 3001 3002 /* Initialize IV */ 3003 ret = crypt_ctr_ivmode(ti, ivmode); 3004 if (ret < 0) 3005 return ret; 3006 3007 /* Initialize and set key */ 3008 ret = crypt_set_key(cc, key); 3009 if (ret < 0) { 3010 ti->error = "Error decoding and setting key"; 3011 return ret; 3012 } 3013 3014 /* Allocate IV */ 3015 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) { 3016 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts); 3017 if (ret < 0) { 3018 ti->error = "Error creating IV"; 3019 return ret; 3020 } 3021 } 3022 3023 /* Initialize IV (set keys for ESSIV etc) */ 3024 if (cc->iv_gen_ops && cc->iv_gen_ops->init) { 3025 ret = cc->iv_gen_ops->init(cc); 3026 if (ret < 0) { 3027 ti->error = "Error initialising IV"; 3028 return ret; 3029 } 3030 } 3031 3032 /* wipe the kernel key payload copy */ 3033 if (cc->key_string) 3034 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3035 3036 return ret; 3037 } 3038 3039 static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv) 3040 { 3041 struct crypt_config *cc = ti->private; 3042 struct dm_arg_set as; 3043 static const struct dm_arg _args[] = { 3044 {0, 8, "Invalid number of feature args"}, 3045 }; 3046 unsigned int opt_params, val; 3047 const char *opt_string, *sval; 3048 char dummy; 3049 int ret; 3050 3051 /* Optional parameters */ 3052 as.argc = argc; 3053 as.argv = argv; 3054 3055 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error); 3056 if (ret) 3057 return ret; 3058 3059 while (opt_params--) { 3060 opt_string = dm_shift_arg(&as); 3061 if (!opt_string) { 3062 ti->error = "Not enough feature arguments"; 3063 return -EINVAL; 3064 } 3065 3066 if (!strcasecmp(opt_string, "allow_discards")) 3067 ti->num_discard_bios = 1; 3068 3069 else if (!strcasecmp(opt_string, "same_cpu_crypt")) 3070 set_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3071 3072 else if (!strcasecmp(opt_string, "submit_from_crypt_cpus")) 3073 set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3074 else if (!strcasecmp(opt_string, "no_read_workqueue")) 3075 set_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3076 else if (!strcasecmp(opt_string, "no_write_workqueue")) 3077 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3078 else if (sscanf(opt_string, "integrity:%u:", &val) == 1) { 3079 if (val == 0 || val > MAX_TAG_SIZE) { 3080 ti->error = "Invalid integrity arguments"; 3081 return -EINVAL; 3082 } 3083 cc->on_disk_tag_size = val; 3084 sval = strchr(opt_string + strlen("integrity:"), ':') + 1; 3085 if (!strcasecmp(sval, "aead")) { 3086 set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 3087 } else if (strcasecmp(sval, "none")) { 3088 ti->error = "Unknown integrity profile"; 3089 return -EINVAL; 3090 } 3091 3092 cc->cipher_auth = kstrdup(sval, GFP_KERNEL); 3093 if (!cc->cipher_auth) 3094 return -ENOMEM; 3095 } else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) { 3096 if (cc->sector_size < (1 << SECTOR_SHIFT) || 3097 cc->sector_size > 4096 || 3098 (cc->sector_size & (cc->sector_size - 1))) { 3099 ti->error = "Invalid feature value for sector_size"; 3100 return -EINVAL; 3101 } 3102 if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) { 3103 ti->error = "Device size is not multiple of sector_size feature"; 3104 return -EINVAL; 3105 } 3106 cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT; 3107 } else if (!strcasecmp(opt_string, "iv_large_sectors")) 3108 set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3109 else { 3110 ti->error = "Invalid feature arguments"; 3111 return -EINVAL; 3112 } 3113 } 3114 3115 return 0; 3116 } 3117 3118 #ifdef CONFIG_BLK_DEV_ZONED 3119 3120 static int crypt_report_zones(struct dm_target *ti, 3121 struct dm_report_zones_args *args, unsigned int nr_zones) 3122 { 3123 struct crypt_config *cc = ti->private; 3124 sector_t sector = cc->start + dm_target_offset(ti, args->next_sector); 3125 3126 args->start = cc->start; 3127 return blkdev_report_zones(cc->dev->bdev, sector, nr_zones, 3128 dm_report_zones_cb, args); 3129 } 3130 3131 #endif 3132 3133 /* 3134 * Construct an encryption mapping: 3135 * <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start> 3136 */ 3137 static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) 3138 { 3139 struct crypt_config *cc; 3140 const char *devname = dm_table_device_name(ti->table); 3141 int key_size; 3142 unsigned int align_mask; 3143 unsigned long long tmpll; 3144 int ret; 3145 size_t iv_size_padding, additional_req_size; 3146 char dummy; 3147 3148 if (argc < 5) { 3149 ti->error = "Not enough arguments"; 3150 return -EINVAL; 3151 } 3152 3153 key_size = get_key_size(&argv[1]); 3154 if (key_size < 0) { 3155 ti->error = "Cannot parse key size"; 3156 return -EINVAL; 3157 } 3158 3159 cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL); 3160 if (!cc) { 3161 ti->error = "Cannot allocate encryption context"; 3162 return -ENOMEM; 3163 } 3164 cc->key_size = key_size; 3165 cc->sector_size = (1 << SECTOR_SHIFT); 3166 cc->sector_shift = 0; 3167 3168 ti->private = cc; 3169 3170 spin_lock(&dm_crypt_clients_lock); 3171 dm_crypt_clients_n++; 3172 crypt_calculate_pages_per_client(); 3173 spin_unlock(&dm_crypt_clients_lock); 3174 3175 ret = percpu_counter_init(&cc->n_allocated_pages, 0, GFP_KERNEL); 3176 if (ret < 0) 3177 goto bad; 3178 3179 /* Optional parameters need to be read before cipher constructor */ 3180 if (argc > 5) { 3181 ret = crypt_ctr_optional(ti, argc - 5, &argv[5]); 3182 if (ret) 3183 goto bad; 3184 } 3185 3186 ret = crypt_ctr_cipher(ti, argv[0], argv[1]); 3187 if (ret < 0) 3188 goto bad; 3189 3190 if (crypt_integrity_aead(cc)) { 3191 cc->dmreq_start = sizeof(struct aead_request); 3192 cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc)); 3193 align_mask = crypto_aead_alignmask(any_tfm_aead(cc)); 3194 } else { 3195 cc->dmreq_start = sizeof(struct skcipher_request); 3196 cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc)); 3197 align_mask = crypto_skcipher_alignmask(any_tfm(cc)); 3198 } 3199 cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request)); 3200 3201 if (align_mask < CRYPTO_MINALIGN) { 3202 /* Allocate the padding exactly */ 3203 iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request)) 3204 & align_mask; 3205 } else { 3206 /* 3207 * If the cipher requires greater alignment than kmalloc 3208 * alignment, we don't know the exact position of the 3209 * initialization vector. We must assume worst case. 3210 */ 3211 iv_size_padding = align_mask; 3212 } 3213 3214 /* ...| IV + padding | original IV | original sec. number | bio tag offset | */ 3215 additional_req_size = sizeof(struct dm_crypt_request) + 3216 iv_size_padding + cc->iv_size + 3217 cc->iv_size + 3218 sizeof(uint64_t) + 3219 sizeof(unsigned int); 3220 3221 ret = mempool_init_kmalloc_pool(&cc->req_pool, MIN_IOS, cc->dmreq_start + additional_req_size); 3222 if (ret) { 3223 ti->error = "Cannot allocate crypt request mempool"; 3224 goto bad; 3225 } 3226 3227 cc->per_bio_data_size = ti->per_io_data_size = 3228 ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size, 3229 ARCH_KMALLOC_MINALIGN); 3230 3231 ret = mempool_init(&cc->page_pool, BIO_MAX_PAGES, crypt_page_alloc, crypt_page_free, cc); 3232 if (ret) { 3233 ti->error = "Cannot allocate page mempool"; 3234 goto bad; 3235 } 3236 3237 ret = bioset_init(&cc->bs, MIN_IOS, 0, BIOSET_NEED_BVECS); 3238 if (ret) { 3239 ti->error = "Cannot allocate crypt bioset"; 3240 goto bad; 3241 } 3242 3243 mutex_init(&cc->bio_alloc_lock); 3244 3245 ret = -EINVAL; 3246 if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) || 3247 (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) { 3248 ti->error = "Invalid iv_offset sector"; 3249 goto bad; 3250 } 3251 cc->iv_offset = tmpll; 3252 3253 ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev); 3254 if (ret) { 3255 ti->error = "Device lookup failed"; 3256 goto bad; 3257 } 3258 3259 ret = -EINVAL; 3260 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) { 3261 ti->error = "Invalid device sector"; 3262 goto bad; 3263 } 3264 cc->start = tmpll; 3265 3266 /* 3267 * For zoned block devices, we need to preserve the issuer write 3268 * ordering. To do so, disable write workqueues and force inline 3269 * encryption completion. 3270 */ 3271 if (bdev_is_zoned(cc->dev->bdev)) { 3272 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3273 set_bit(DM_CRYPT_WRITE_INLINE, &cc->flags); 3274 } 3275 3276 if (crypt_integrity_aead(cc) || cc->integrity_iv_size) { 3277 ret = crypt_integrity_ctr(cc, ti); 3278 if (ret) 3279 goto bad; 3280 3281 cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->on_disk_tag_size; 3282 if (!cc->tag_pool_max_sectors) 3283 cc->tag_pool_max_sectors = 1; 3284 3285 ret = mempool_init_kmalloc_pool(&cc->tag_pool, MIN_IOS, 3286 cc->tag_pool_max_sectors * cc->on_disk_tag_size); 3287 if (ret) { 3288 ti->error = "Cannot allocate integrity tags mempool"; 3289 goto bad; 3290 } 3291 3292 cc->tag_pool_max_sectors <<= cc->sector_shift; 3293 } 3294 3295 ret = -ENOMEM; 3296 cc->io_queue = alloc_workqueue("kcryptd_io/%s", WQ_MEM_RECLAIM, 1, devname); 3297 if (!cc->io_queue) { 3298 ti->error = "Couldn't create kcryptd io queue"; 3299 goto bad; 3300 } 3301 3302 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3303 cc->crypt_queue = alloc_workqueue("kcryptd/%s", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 3304 1, devname); 3305 else 3306 cc->crypt_queue = alloc_workqueue("kcryptd/%s", 3307 WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND, 3308 num_online_cpus(), devname); 3309 if (!cc->crypt_queue) { 3310 ti->error = "Couldn't create kcryptd queue"; 3311 goto bad; 3312 } 3313 3314 spin_lock_init(&cc->write_thread_lock); 3315 cc->write_tree = RB_ROOT; 3316 3317 cc->write_thread = kthread_create(dmcrypt_write, cc, "dmcrypt_write/%s", devname); 3318 if (IS_ERR(cc->write_thread)) { 3319 ret = PTR_ERR(cc->write_thread); 3320 cc->write_thread = NULL; 3321 ti->error = "Couldn't spawn write thread"; 3322 goto bad; 3323 } 3324 wake_up_process(cc->write_thread); 3325 3326 ti->num_flush_bios = 1; 3327 3328 return 0; 3329 3330 bad: 3331 crypt_dtr(ti); 3332 return ret; 3333 } 3334 3335 static int crypt_map(struct dm_target *ti, struct bio *bio) 3336 { 3337 struct dm_crypt_io *io; 3338 struct crypt_config *cc = ti->private; 3339 3340 /* 3341 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues. 3342 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight 3343 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters 3344 */ 3345 if (unlikely(bio->bi_opf & REQ_PREFLUSH || 3346 bio_op(bio) == REQ_OP_DISCARD)) { 3347 bio_set_dev(bio, cc->dev->bdev); 3348 if (bio_sectors(bio)) 3349 bio->bi_iter.bi_sector = cc->start + 3350 dm_target_offset(ti, bio->bi_iter.bi_sector); 3351 return DM_MAPIO_REMAPPED; 3352 } 3353 3354 /* 3355 * Check if bio is too large, split as needed. 3356 */ 3357 if (unlikely(bio->bi_iter.bi_size > (BIO_MAX_PAGES << PAGE_SHIFT)) && 3358 (bio_data_dir(bio) == WRITE || cc->on_disk_tag_size)) 3359 dm_accept_partial_bio(bio, ((BIO_MAX_PAGES << PAGE_SHIFT) >> SECTOR_SHIFT)); 3360 3361 /* 3362 * Ensure that bio is a multiple of internal sector encryption size 3363 * and is aligned to this size as defined in IO hints. 3364 */ 3365 if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0)) 3366 return DM_MAPIO_KILL; 3367 3368 if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1))) 3369 return DM_MAPIO_KILL; 3370 3371 io = dm_per_bio_data(bio, cc->per_bio_data_size); 3372 crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector)); 3373 3374 if (cc->on_disk_tag_size) { 3375 unsigned tag_len = cc->on_disk_tag_size * (bio_sectors(bio) >> cc->sector_shift); 3376 3377 if (unlikely(tag_len > KMALLOC_MAX_SIZE) || 3378 unlikely(!(io->integrity_metadata = kmalloc(tag_len, 3379 GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN)))) { 3380 if (bio_sectors(bio) > cc->tag_pool_max_sectors) 3381 dm_accept_partial_bio(bio, cc->tag_pool_max_sectors); 3382 io->integrity_metadata = mempool_alloc(&cc->tag_pool, GFP_NOIO); 3383 io->integrity_metadata_from_pool = true; 3384 } 3385 } 3386 3387 if (crypt_integrity_aead(cc)) 3388 io->ctx.r.req_aead = (struct aead_request *)(io + 1); 3389 else 3390 io->ctx.r.req = (struct skcipher_request *)(io + 1); 3391 3392 if (bio_data_dir(io->base_bio) == READ) { 3393 if (kcryptd_io_read(io, GFP_NOWAIT)) 3394 kcryptd_queue_read(io); 3395 } else 3396 kcryptd_queue_crypt(io); 3397 3398 return DM_MAPIO_SUBMITTED; 3399 } 3400 3401 static void crypt_status(struct dm_target *ti, status_type_t type, 3402 unsigned status_flags, char *result, unsigned maxlen) 3403 { 3404 struct crypt_config *cc = ti->private; 3405 unsigned i, sz = 0; 3406 int num_feature_args = 0; 3407 3408 switch (type) { 3409 case STATUSTYPE_INFO: 3410 result[0] = '\0'; 3411 break; 3412 3413 case STATUSTYPE_TABLE: 3414 DMEMIT("%s ", cc->cipher_string); 3415 3416 if (cc->key_size > 0) { 3417 if (cc->key_string) 3418 DMEMIT(":%u:%s", cc->key_size, cc->key_string); 3419 else 3420 for (i = 0; i < cc->key_size; i++) 3421 DMEMIT("%02x", cc->key[i]); 3422 } else 3423 DMEMIT("-"); 3424 3425 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, 3426 cc->dev->name, (unsigned long long)cc->start); 3427 3428 num_feature_args += !!ti->num_discard_bios; 3429 num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3430 num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3431 num_feature_args += test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3432 num_feature_args += test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3433 num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT); 3434 num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3435 if (cc->on_disk_tag_size) 3436 num_feature_args++; 3437 if (num_feature_args) { 3438 DMEMIT(" %d", num_feature_args); 3439 if (ti->num_discard_bios) 3440 DMEMIT(" allow_discards"); 3441 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3442 DMEMIT(" same_cpu_crypt"); 3443 if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) 3444 DMEMIT(" submit_from_crypt_cpus"); 3445 if (test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) 3446 DMEMIT(" no_read_workqueue"); 3447 if (test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) 3448 DMEMIT(" no_write_workqueue"); 3449 if (cc->on_disk_tag_size) 3450 DMEMIT(" integrity:%u:%s", cc->on_disk_tag_size, cc->cipher_auth); 3451 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3452 DMEMIT(" sector_size:%d", cc->sector_size); 3453 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 3454 DMEMIT(" iv_large_sectors"); 3455 } 3456 3457 break; 3458 } 3459 } 3460 3461 static void crypt_postsuspend(struct dm_target *ti) 3462 { 3463 struct crypt_config *cc = ti->private; 3464 3465 set_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3466 } 3467 3468 static int crypt_preresume(struct dm_target *ti) 3469 { 3470 struct crypt_config *cc = ti->private; 3471 3472 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { 3473 DMERR("aborting resume - crypt key is not set."); 3474 return -EAGAIN; 3475 } 3476 3477 return 0; 3478 } 3479 3480 static void crypt_resume(struct dm_target *ti) 3481 { 3482 struct crypt_config *cc = ti->private; 3483 3484 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3485 } 3486 3487 /* Message interface 3488 * key set <key> 3489 * key wipe 3490 */ 3491 static int crypt_message(struct dm_target *ti, unsigned argc, char **argv, 3492 char *result, unsigned maxlen) 3493 { 3494 struct crypt_config *cc = ti->private; 3495 int key_size, ret = -EINVAL; 3496 3497 if (argc < 2) 3498 goto error; 3499 3500 if (!strcasecmp(argv[0], "key")) { 3501 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { 3502 DMWARN("not suspended during key manipulation."); 3503 return -EINVAL; 3504 } 3505 if (argc == 3 && !strcasecmp(argv[1], "set")) { 3506 /* The key size may not be changed. */ 3507 key_size = get_key_size(&argv[2]); 3508 if (key_size < 0 || cc->key_size != key_size) { 3509 memset(argv[2], '0', strlen(argv[2])); 3510 return -EINVAL; 3511 } 3512 3513 ret = crypt_set_key(cc, argv[2]); 3514 if (ret) 3515 return ret; 3516 if (cc->iv_gen_ops && cc->iv_gen_ops->init) 3517 ret = cc->iv_gen_ops->init(cc); 3518 /* wipe the kernel key payload copy */ 3519 if (cc->key_string) 3520 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3521 return ret; 3522 } 3523 if (argc == 2 && !strcasecmp(argv[1], "wipe")) 3524 return crypt_wipe_key(cc); 3525 } 3526 3527 error: 3528 DMWARN("unrecognised message received."); 3529 return -EINVAL; 3530 } 3531 3532 static int crypt_iterate_devices(struct dm_target *ti, 3533 iterate_devices_callout_fn fn, void *data) 3534 { 3535 struct crypt_config *cc = ti->private; 3536 3537 return fn(ti, cc->dev, cc->start, ti->len, data); 3538 } 3539 3540 static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits) 3541 { 3542 struct crypt_config *cc = ti->private; 3543 3544 /* 3545 * Unfortunate constraint that is required to avoid the potential 3546 * for exceeding underlying device's max_segments limits -- due to 3547 * crypt_alloc_buffer() possibly allocating pages for the encryption 3548 * bio that are not as physically contiguous as the original bio. 3549 */ 3550 limits->max_segment_size = PAGE_SIZE; 3551 3552 limits->logical_block_size = 3553 max_t(unsigned, limits->logical_block_size, cc->sector_size); 3554 limits->physical_block_size = 3555 max_t(unsigned, limits->physical_block_size, cc->sector_size); 3556 limits->io_min = max_t(unsigned, limits->io_min, cc->sector_size); 3557 } 3558 3559 static struct target_type crypt_target = { 3560 .name = "crypt", 3561 .version = {1, 22, 0}, 3562 .module = THIS_MODULE, 3563 .ctr = crypt_ctr, 3564 .dtr = crypt_dtr, 3565 #ifdef CONFIG_BLK_DEV_ZONED 3566 .features = DM_TARGET_ZONED_HM, 3567 .report_zones = crypt_report_zones, 3568 #endif 3569 .map = crypt_map, 3570 .status = crypt_status, 3571 .postsuspend = crypt_postsuspend, 3572 .preresume = crypt_preresume, 3573 .resume = crypt_resume, 3574 .message = crypt_message, 3575 .iterate_devices = crypt_iterate_devices, 3576 .io_hints = crypt_io_hints, 3577 }; 3578 3579 static int __init dm_crypt_init(void) 3580 { 3581 int r; 3582 3583 r = dm_register_target(&crypt_target); 3584 if (r < 0) 3585 DMERR("register failed %d", r); 3586 3587 return r; 3588 } 3589 3590 static void __exit dm_crypt_exit(void) 3591 { 3592 dm_unregister_target(&crypt_target); 3593 } 3594 3595 module_init(dm_crypt_init); 3596 module_exit(dm_crypt_exit); 3597 3598 MODULE_AUTHOR("Jana Saout <jana@saout.de>"); 3599 MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); 3600 MODULE_LICENSE("GPL"); 3601