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