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 #define DM_MSG_PREFIX "crypt" 46 47 /* 48 * context holding the current state of a multi-part conversion 49 */ 50 struct convert_context { 51 struct completion restart; 52 struct bio *bio_in; 53 struct bio *bio_out; 54 struct bvec_iter iter_in; 55 struct bvec_iter iter_out; 56 u64 cc_sector; 57 atomic_t cc_pending; 58 union { 59 struct skcipher_request *req; 60 struct aead_request *req_aead; 61 } r; 62 63 }; 64 65 /* 66 * per bio private data 67 */ 68 struct dm_crypt_io { 69 struct crypt_config *cc; 70 struct bio *base_bio; 71 u8 *integrity_metadata; 72 bool integrity_metadata_from_pool; 73 struct work_struct work; 74 struct tasklet_struct tasklet; 75 76 struct convert_context ctx; 77 78 atomic_t io_pending; 79 blk_status_t error; 80 sector_t sector; 81 82 struct rb_node rb_node; 83 } CRYPTO_MINALIGN_ATTR; 84 85 struct dm_crypt_request { 86 struct convert_context *ctx; 87 struct scatterlist sg_in[4]; 88 struct scatterlist sg_out[4]; 89 u64 iv_sector; 90 }; 91 92 struct crypt_config; 93 94 struct crypt_iv_operations { 95 int (*ctr)(struct crypt_config *cc, struct dm_target *ti, 96 const char *opts); 97 void (*dtr)(struct crypt_config *cc); 98 int (*init)(struct crypt_config *cc); 99 int (*wipe)(struct crypt_config *cc); 100 int (*generator)(struct crypt_config *cc, u8 *iv, 101 struct dm_crypt_request *dmreq); 102 int (*post)(struct crypt_config *cc, u8 *iv, 103 struct dm_crypt_request *dmreq); 104 }; 105 106 struct iv_benbi_private { 107 int shift; 108 }; 109 110 #define LMK_SEED_SIZE 64 /* hash + 0 */ 111 struct iv_lmk_private { 112 struct crypto_shash *hash_tfm; 113 u8 *seed; 114 }; 115 116 #define TCW_WHITENING_SIZE 16 117 struct iv_tcw_private { 118 struct crypto_shash *crc32_tfm; 119 u8 *iv_seed; 120 u8 *whitening; 121 }; 122 123 #define ELEPHANT_MAX_KEY_SIZE 32 124 struct iv_elephant_private { 125 struct crypto_skcipher *tfm; 126 }; 127 128 /* 129 * Crypt: maps a linear range of a block device 130 * and encrypts / decrypts at the same time. 131 */ 132 enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID, 133 DM_CRYPT_SAME_CPU, DM_CRYPT_NO_OFFLOAD, 134 DM_CRYPT_NO_READ_WORKQUEUE, DM_CRYPT_NO_WRITE_WORKQUEUE, 135 DM_CRYPT_WRITE_INLINE }; 136 137 enum cipher_flags { 138 CRYPT_MODE_INTEGRITY_AEAD, /* Use authenticated mode for cipher */ 139 CRYPT_IV_LARGE_SECTORS, /* Calculate IV from sector_size, not 512B sectors */ 140 CRYPT_ENCRYPT_PREPROCESS, /* Must preprocess data for encryption (elephant) */ 141 }; 142 143 /* 144 * The fields in here must be read only after initialization. 145 */ 146 struct crypt_config { 147 struct dm_dev *dev; 148 sector_t start; 149 150 struct percpu_counter n_allocated_pages; 151 152 struct workqueue_struct *io_queue; 153 struct workqueue_struct *crypt_queue; 154 155 spinlock_t write_thread_lock; 156 struct task_struct *write_thread; 157 struct rb_root write_tree; 158 159 char *cipher_string; 160 char *cipher_auth; 161 char *key_string; 162 163 const struct crypt_iv_operations *iv_gen_ops; 164 union { 165 struct iv_benbi_private benbi; 166 struct iv_lmk_private lmk; 167 struct iv_tcw_private tcw; 168 struct iv_elephant_private elephant; 169 } iv_gen_private; 170 u64 iv_offset; 171 unsigned int iv_size; 172 unsigned short int sector_size; 173 unsigned char sector_shift; 174 175 union { 176 struct crypto_skcipher **tfms; 177 struct crypto_aead **tfms_aead; 178 } cipher_tfm; 179 unsigned tfms_count; 180 unsigned long cipher_flags; 181 182 /* 183 * Layout of each crypto request: 184 * 185 * struct skcipher_request 186 * context 187 * padding 188 * struct dm_crypt_request 189 * padding 190 * IV 191 * 192 * The padding is added so that dm_crypt_request and the IV are 193 * correctly aligned. 194 */ 195 unsigned int dmreq_start; 196 197 unsigned int per_bio_data_size; 198 199 unsigned long flags; 200 unsigned int key_size; 201 unsigned int key_parts; /* independent parts in key buffer */ 202 unsigned int key_extra_size; /* additional keys length */ 203 unsigned int key_mac_size; /* MAC key size for authenc(...) */ 204 205 unsigned int integrity_tag_size; 206 unsigned int integrity_iv_size; 207 unsigned int on_disk_tag_size; 208 209 /* 210 * pool for per bio private data, crypto requests, 211 * encryption requeusts/buffer pages and integrity tags 212 */ 213 unsigned tag_pool_max_sectors; 214 mempool_t tag_pool; 215 mempool_t req_pool; 216 mempool_t page_pool; 217 218 struct bio_set bs; 219 struct mutex bio_alloc_lock; 220 221 u8 *authenc_key; /* space for keys in authenc() format (if used) */ 222 u8 key[]; 223 }; 224 225 #define MIN_IOS 64 226 #define MAX_TAG_SIZE 480 227 #define POOL_ENTRY_SIZE 512 228 229 static DEFINE_SPINLOCK(dm_crypt_clients_lock); 230 static unsigned dm_crypt_clients_n = 0; 231 static volatile unsigned long dm_crypt_pages_per_client; 232 #define DM_CRYPT_MEMORY_PERCENT 2 233 #define DM_CRYPT_MIN_PAGES_PER_CLIENT (BIO_MAX_VECS * 16) 234 235 static void clone_init(struct dm_crypt_io *, struct bio *); 236 static void kcryptd_queue_crypt(struct dm_crypt_io *io); 237 static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 238 struct scatterlist *sg); 239 240 static bool crypt_integrity_aead(struct crypt_config *cc); 241 242 /* 243 * Use this to access cipher attributes that are independent of the key. 244 */ 245 static struct crypto_skcipher *any_tfm(struct crypt_config *cc) 246 { 247 return cc->cipher_tfm.tfms[0]; 248 } 249 250 static struct crypto_aead *any_tfm_aead(struct crypt_config *cc) 251 { 252 return cc->cipher_tfm.tfms_aead[0]; 253 } 254 255 /* 256 * Different IV generation algorithms: 257 * 258 * plain: the initial vector is the 32-bit little-endian version of the sector 259 * number, padded with zeros if necessary. 260 * 261 * plain64: the initial vector is the 64-bit little-endian version of the sector 262 * number, padded with zeros if necessary. 263 * 264 * plain64be: the initial vector is the 64-bit big-endian version of the sector 265 * number, padded with zeros if necessary. 266 * 267 * essiv: "encrypted sector|salt initial vector", the sector number is 268 * encrypted with the bulk cipher using a salt as key. The salt 269 * should be derived from the bulk cipher's key via hashing. 270 * 271 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 272 * (needed for LRW-32-AES and possible other narrow block modes) 273 * 274 * null: the initial vector is always zero. Provides compatibility with 275 * obsolete loop_fish2 devices. Do not use for new devices. 276 * 277 * lmk: Compatible implementation of the block chaining mode used 278 * by the Loop-AES block device encryption system 279 * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/ 280 * It operates on full 512 byte sectors and uses CBC 281 * with an IV derived from the sector number, the data and 282 * optionally extra IV seed. 283 * This means that after decryption the first block 284 * of sector must be tweaked according to decrypted data. 285 * Loop-AES can use three encryption schemes: 286 * version 1: is plain aes-cbc mode 287 * version 2: uses 64 multikey scheme with lmk IV generator 288 * version 3: the same as version 2 with additional IV seed 289 * (it uses 65 keys, last key is used as IV seed) 290 * 291 * tcw: Compatible implementation of the block chaining mode used 292 * by the TrueCrypt device encryption system (prior to version 4.1). 293 * For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat 294 * It operates on full 512 byte sectors and uses CBC 295 * with an IV derived from initial key and the sector number. 296 * In addition, whitening value is applied on every sector, whitening 297 * is calculated from initial key, sector number and mixed using CRC32. 298 * Note that this encryption scheme is vulnerable to watermarking attacks 299 * and should be used for old compatible containers access only. 300 * 301 * eboiv: Encrypted byte-offset IV (used in Bitlocker in CBC mode) 302 * The IV is encrypted little-endian byte-offset (with the same key 303 * and cipher as the volume). 304 * 305 * elephant: The extended version of eboiv with additional Elephant diffuser 306 * used with Bitlocker CBC mode. 307 * This mode was used in older Windows systems 308 * https://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf 309 */ 310 311 static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, 312 struct dm_crypt_request *dmreq) 313 { 314 memset(iv, 0, cc->iv_size); 315 *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff); 316 317 return 0; 318 } 319 320 static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv, 321 struct dm_crypt_request *dmreq) 322 { 323 memset(iv, 0, cc->iv_size); 324 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 325 326 return 0; 327 } 328 329 static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv, 330 struct dm_crypt_request *dmreq) 331 { 332 memset(iv, 0, cc->iv_size); 333 /* iv_size is at least of size u64; usually it is 16 bytes */ 334 *(__be64 *)&iv[cc->iv_size - sizeof(u64)] = cpu_to_be64(dmreq->iv_sector); 335 336 return 0; 337 } 338 339 static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, 340 struct dm_crypt_request *dmreq) 341 { 342 /* 343 * ESSIV encryption of the IV is now handled by the crypto API, 344 * so just pass the plain sector number here. 345 */ 346 memset(iv, 0, cc->iv_size); 347 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 348 349 return 0; 350 } 351 352 static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, 353 const char *opts) 354 { 355 unsigned bs; 356 int log; 357 358 if (crypt_integrity_aead(cc)) 359 bs = crypto_aead_blocksize(any_tfm_aead(cc)); 360 else 361 bs = crypto_skcipher_blocksize(any_tfm(cc)); 362 log = ilog2(bs); 363 364 /* we need to calculate how far we must shift the sector count 365 * to get the cipher block count, we use this shift in _gen */ 366 367 if (1 << log != bs) { 368 ti->error = "cypher blocksize is not a power of 2"; 369 return -EINVAL; 370 } 371 372 if (log > 9) { 373 ti->error = "cypher blocksize is > 512"; 374 return -EINVAL; 375 } 376 377 cc->iv_gen_private.benbi.shift = 9 - log; 378 379 return 0; 380 } 381 382 static void crypt_iv_benbi_dtr(struct crypt_config *cc) 383 { 384 } 385 386 static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, 387 struct dm_crypt_request *dmreq) 388 { 389 __be64 val; 390 391 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ 392 393 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1); 394 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); 395 396 return 0; 397 } 398 399 static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, 400 struct dm_crypt_request *dmreq) 401 { 402 memset(iv, 0, cc->iv_size); 403 404 return 0; 405 } 406 407 static void crypt_iv_lmk_dtr(struct crypt_config *cc) 408 { 409 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 410 411 if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm)) 412 crypto_free_shash(lmk->hash_tfm); 413 lmk->hash_tfm = NULL; 414 415 kfree_sensitive(lmk->seed); 416 lmk->seed = NULL; 417 } 418 419 static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti, 420 const char *opts) 421 { 422 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 423 424 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 425 ti->error = "Unsupported sector size for LMK"; 426 return -EINVAL; 427 } 428 429 lmk->hash_tfm = crypto_alloc_shash("md5", 0, 430 CRYPTO_ALG_ALLOCATES_MEMORY); 431 if (IS_ERR(lmk->hash_tfm)) { 432 ti->error = "Error initializing LMK hash"; 433 return PTR_ERR(lmk->hash_tfm); 434 } 435 436 /* No seed in LMK version 2 */ 437 if (cc->key_parts == cc->tfms_count) { 438 lmk->seed = NULL; 439 return 0; 440 } 441 442 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL); 443 if (!lmk->seed) { 444 crypt_iv_lmk_dtr(cc); 445 ti->error = "Error kmallocing seed storage in LMK"; 446 return -ENOMEM; 447 } 448 449 return 0; 450 } 451 452 static int crypt_iv_lmk_init(struct crypt_config *cc) 453 { 454 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 455 int subkey_size = cc->key_size / cc->key_parts; 456 457 /* LMK seed is on the position of LMK_KEYS + 1 key */ 458 if (lmk->seed) 459 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size), 460 crypto_shash_digestsize(lmk->hash_tfm)); 461 462 return 0; 463 } 464 465 static int crypt_iv_lmk_wipe(struct crypt_config *cc) 466 { 467 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 468 469 if (lmk->seed) 470 memset(lmk->seed, 0, LMK_SEED_SIZE); 471 472 return 0; 473 } 474 475 static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv, 476 struct dm_crypt_request *dmreq, 477 u8 *data) 478 { 479 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 480 SHASH_DESC_ON_STACK(desc, lmk->hash_tfm); 481 struct md5_state md5state; 482 __le32 buf[4]; 483 int i, r; 484 485 desc->tfm = lmk->hash_tfm; 486 487 r = crypto_shash_init(desc); 488 if (r) 489 return r; 490 491 if (lmk->seed) { 492 r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE); 493 if (r) 494 return r; 495 } 496 497 /* Sector is always 512B, block size 16, add data of blocks 1-31 */ 498 r = crypto_shash_update(desc, data + 16, 16 * 31); 499 if (r) 500 return r; 501 502 /* Sector is cropped to 56 bits here */ 503 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF); 504 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000); 505 buf[2] = cpu_to_le32(4024); 506 buf[3] = 0; 507 r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf)); 508 if (r) 509 return r; 510 511 /* No MD5 padding here */ 512 r = crypto_shash_export(desc, &md5state); 513 if (r) 514 return r; 515 516 for (i = 0; i < MD5_HASH_WORDS; i++) 517 __cpu_to_le32s(&md5state.hash[i]); 518 memcpy(iv, &md5state.hash, cc->iv_size); 519 520 return 0; 521 } 522 523 static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv, 524 struct dm_crypt_request *dmreq) 525 { 526 struct scatterlist *sg; 527 u8 *src; 528 int r = 0; 529 530 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 531 sg = crypt_get_sg_data(cc, dmreq->sg_in); 532 src = kmap_atomic(sg_page(sg)); 533 r = crypt_iv_lmk_one(cc, iv, dmreq, src + sg->offset); 534 kunmap_atomic(src); 535 } else 536 memset(iv, 0, cc->iv_size); 537 538 return r; 539 } 540 541 static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv, 542 struct dm_crypt_request *dmreq) 543 { 544 struct scatterlist *sg; 545 u8 *dst; 546 int r; 547 548 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) 549 return 0; 550 551 sg = crypt_get_sg_data(cc, dmreq->sg_out); 552 dst = kmap_atomic(sg_page(sg)); 553 r = crypt_iv_lmk_one(cc, iv, dmreq, dst + sg->offset); 554 555 /* Tweak the first block of plaintext sector */ 556 if (!r) 557 crypto_xor(dst + sg->offset, iv, cc->iv_size); 558 559 kunmap_atomic(dst); 560 return r; 561 } 562 563 static void crypt_iv_tcw_dtr(struct crypt_config *cc) 564 { 565 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 566 567 kfree_sensitive(tcw->iv_seed); 568 tcw->iv_seed = NULL; 569 kfree_sensitive(tcw->whitening); 570 tcw->whitening = NULL; 571 572 if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm)) 573 crypto_free_shash(tcw->crc32_tfm); 574 tcw->crc32_tfm = NULL; 575 } 576 577 static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti, 578 const char *opts) 579 { 580 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 581 582 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 583 ti->error = "Unsupported sector size for TCW"; 584 return -EINVAL; 585 } 586 587 if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) { 588 ti->error = "Wrong key size for TCW"; 589 return -EINVAL; 590 } 591 592 tcw->crc32_tfm = crypto_alloc_shash("crc32", 0, 593 CRYPTO_ALG_ALLOCATES_MEMORY); 594 if (IS_ERR(tcw->crc32_tfm)) { 595 ti->error = "Error initializing CRC32 in TCW"; 596 return PTR_ERR(tcw->crc32_tfm); 597 } 598 599 tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL); 600 tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL); 601 if (!tcw->iv_seed || !tcw->whitening) { 602 crypt_iv_tcw_dtr(cc); 603 ti->error = "Error allocating seed storage in TCW"; 604 return -ENOMEM; 605 } 606 607 return 0; 608 } 609 610 static int crypt_iv_tcw_init(struct crypt_config *cc) 611 { 612 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 613 int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE; 614 615 memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size); 616 memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size], 617 TCW_WHITENING_SIZE); 618 619 return 0; 620 } 621 622 static int crypt_iv_tcw_wipe(struct crypt_config *cc) 623 { 624 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 625 626 memset(tcw->iv_seed, 0, cc->iv_size); 627 memset(tcw->whitening, 0, TCW_WHITENING_SIZE); 628 629 return 0; 630 } 631 632 static int crypt_iv_tcw_whitening(struct crypt_config *cc, 633 struct dm_crypt_request *dmreq, 634 u8 *data) 635 { 636 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 637 __le64 sector = cpu_to_le64(dmreq->iv_sector); 638 u8 buf[TCW_WHITENING_SIZE]; 639 SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm); 640 int i, r; 641 642 /* xor whitening with sector number */ 643 crypto_xor_cpy(buf, tcw->whitening, (u8 *)§or, 8); 644 crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)§or, 8); 645 646 /* calculate crc32 for every 32bit part and xor it */ 647 desc->tfm = tcw->crc32_tfm; 648 for (i = 0; i < 4; i++) { 649 r = crypto_shash_init(desc); 650 if (r) 651 goto out; 652 r = crypto_shash_update(desc, &buf[i * 4], 4); 653 if (r) 654 goto out; 655 r = crypto_shash_final(desc, &buf[i * 4]); 656 if (r) 657 goto out; 658 } 659 crypto_xor(&buf[0], &buf[12], 4); 660 crypto_xor(&buf[4], &buf[8], 4); 661 662 /* apply whitening (8 bytes) to whole sector */ 663 for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++) 664 crypto_xor(data + i * 8, buf, 8); 665 out: 666 memzero_explicit(buf, sizeof(buf)); 667 return r; 668 } 669 670 static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv, 671 struct dm_crypt_request *dmreq) 672 { 673 struct scatterlist *sg; 674 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 675 __le64 sector = cpu_to_le64(dmreq->iv_sector); 676 u8 *src; 677 int r = 0; 678 679 /* Remove whitening from ciphertext */ 680 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 681 sg = crypt_get_sg_data(cc, dmreq->sg_in); 682 src = kmap_atomic(sg_page(sg)); 683 r = crypt_iv_tcw_whitening(cc, dmreq, src + sg->offset); 684 kunmap_atomic(src); 685 } 686 687 /* Calculate IV */ 688 crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)§or, 8); 689 if (cc->iv_size > 8) 690 crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)§or, 691 cc->iv_size - 8); 692 693 return r; 694 } 695 696 static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv, 697 struct dm_crypt_request *dmreq) 698 { 699 struct scatterlist *sg; 700 u8 *dst; 701 int r; 702 703 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 704 return 0; 705 706 /* Apply whitening on ciphertext */ 707 sg = crypt_get_sg_data(cc, dmreq->sg_out); 708 dst = kmap_atomic(sg_page(sg)); 709 r = crypt_iv_tcw_whitening(cc, dmreq, dst + sg->offset); 710 kunmap_atomic(dst); 711 712 return r; 713 } 714 715 static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv, 716 struct dm_crypt_request *dmreq) 717 { 718 /* Used only for writes, there must be an additional space to store IV */ 719 get_random_bytes(iv, cc->iv_size); 720 return 0; 721 } 722 723 static int crypt_iv_eboiv_ctr(struct crypt_config *cc, struct dm_target *ti, 724 const char *opts) 725 { 726 if (crypt_integrity_aead(cc)) { 727 ti->error = "AEAD transforms not supported for EBOIV"; 728 return -EINVAL; 729 } 730 731 if (crypto_skcipher_blocksize(any_tfm(cc)) != cc->iv_size) { 732 ti->error = "Block size of EBOIV cipher does " 733 "not match IV size of block cipher"; 734 return -EINVAL; 735 } 736 737 return 0; 738 } 739 740 static int crypt_iv_eboiv_gen(struct crypt_config *cc, u8 *iv, 741 struct dm_crypt_request *dmreq) 742 { 743 u8 buf[MAX_CIPHER_BLOCKSIZE] __aligned(__alignof__(__le64)); 744 struct skcipher_request *req; 745 struct scatterlist src, dst; 746 DECLARE_CRYPTO_WAIT(wait); 747 int err; 748 749 req = skcipher_request_alloc(any_tfm(cc), GFP_NOIO); 750 if (!req) 751 return -ENOMEM; 752 753 memset(buf, 0, cc->iv_size); 754 *(__le64 *)buf = cpu_to_le64(dmreq->iv_sector * cc->sector_size); 755 756 sg_init_one(&src, page_address(ZERO_PAGE(0)), cc->iv_size); 757 sg_init_one(&dst, iv, cc->iv_size); 758 skcipher_request_set_crypt(req, &src, &dst, cc->iv_size, buf); 759 skcipher_request_set_callback(req, 0, crypto_req_done, &wait); 760 err = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 761 skcipher_request_free(req); 762 763 return err; 764 } 765 766 static void crypt_iv_elephant_dtr(struct crypt_config *cc) 767 { 768 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 769 770 crypto_free_skcipher(elephant->tfm); 771 elephant->tfm = NULL; 772 } 773 774 static int crypt_iv_elephant_ctr(struct crypt_config *cc, struct dm_target *ti, 775 const char *opts) 776 { 777 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 778 int r; 779 780 elephant->tfm = crypto_alloc_skcipher("ecb(aes)", 0, 781 CRYPTO_ALG_ALLOCATES_MEMORY); 782 if (IS_ERR(elephant->tfm)) { 783 r = PTR_ERR(elephant->tfm); 784 elephant->tfm = NULL; 785 return r; 786 } 787 788 r = crypt_iv_eboiv_ctr(cc, ti, NULL); 789 if (r) 790 crypt_iv_elephant_dtr(cc); 791 return r; 792 } 793 794 static void diffuser_disk_to_cpu(u32 *d, size_t n) 795 { 796 #ifndef __LITTLE_ENDIAN 797 int i; 798 799 for (i = 0; i < n; i++) 800 d[i] = le32_to_cpu((__le32)d[i]); 801 #endif 802 } 803 804 static void diffuser_cpu_to_disk(__le32 *d, size_t n) 805 { 806 #ifndef __LITTLE_ENDIAN 807 int i; 808 809 for (i = 0; i < n; i++) 810 d[i] = cpu_to_le32((u32)d[i]); 811 #endif 812 } 813 814 static void diffuser_a_decrypt(u32 *d, size_t n) 815 { 816 int i, i1, i2, i3; 817 818 for (i = 0; i < 5; i++) { 819 i1 = 0; 820 i2 = n - 2; 821 i3 = n - 5; 822 823 while (i1 < (n - 1)) { 824 d[i1] += d[i2] ^ (d[i3] << 9 | d[i3] >> 23); 825 i1++; i2++; i3++; 826 827 if (i3 >= n) 828 i3 -= n; 829 830 d[i1] += d[i2] ^ d[i3]; 831 i1++; i2++; i3++; 832 833 if (i2 >= n) 834 i2 -= n; 835 836 d[i1] += d[i2] ^ (d[i3] << 13 | d[i3] >> 19); 837 i1++; i2++; i3++; 838 839 d[i1] += d[i2] ^ d[i3]; 840 i1++; i2++; i3++; 841 } 842 } 843 } 844 845 static void diffuser_a_encrypt(u32 *d, size_t n) 846 { 847 int i, i1, i2, i3; 848 849 for (i = 0; i < 5; i++) { 850 i1 = n - 1; 851 i2 = n - 2 - 1; 852 i3 = n - 5 - 1; 853 854 while (i1 > 0) { 855 d[i1] -= d[i2] ^ d[i3]; 856 i1--; i2--; i3--; 857 858 d[i1] -= d[i2] ^ (d[i3] << 13 | d[i3] >> 19); 859 i1--; i2--; i3--; 860 861 if (i2 < 0) 862 i2 += n; 863 864 d[i1] -= d[i2] ^ d[i3]; 865 i1--; i2--; i3--; 866 867 if (i3 < 0) 868 i3 += n; 869 870 d[i1] -= d[i2] ^ (d[i3] << 9 | d[i3] >> 23); 871 i1--; i2--; i3--; 872 } 873 } 874 } 875 876 static void diffuser_b_decrypt(u32 *d, size_t n) 877 { 878 int i, i1, i2, i3; 879 880 for (i = 0; i < 3; i++) { 881 i1 = 0; 882 i2 = 2; 883 i3 = 5; 884 885 while (i1 < (n - 1)) { 886 d[i1] += d[i2] ^ d[i3]; 887 i1++; i2++; i3++; 888 889 d[i1] += d[i2] ^ (d[i3] << 10 | d[i3] >> 22); 890 i1++; i2++; i3++; 891 892 if (i2 >= n) 893 i2 -= n; 894 895 d[i1] += d[i2] ^ d[i3]; 896 i1++; i2++; i3++; 897 898 if (i3 >= n) 899 i3 -= n; 900 901 d[i1] += d[i2] ^ (d[i3] << 25 | d[i3] >> 7); 902 i1++; i2++; i3++; 903 } 904 } 905 } 906 907 static void diffuser_b_encrypt(u32 *d, size_t n) 908 { 909 int i, i1, i2, i3; 910 911 for (i = 0; i < 3; i++) { 912 i1 = n - 1; 913 i2 = 2 - 1; 914 i3 = 5 - 1; 915 916 while (i1 > 0) { 917 d[i1] -= d[i2] ^ (d[i3] << 25 | d[i3] >> 7); 918 i1--; i2--; i3--; 919 920 if (i3 < 0) 921 i3 += n; 922 923 d[i1] -= d[i2] ^ d[i3]; 924 i1--; i2--; i3--; 925 926 if (i2 < 0) 927 i2 += n; 928 929 d[i1] -= d[i2] ^ (d[i3] << 10 | d[i3] >> 22); 930 i1--; i2--; i3--; 931 932 d[i1] -= d[i2] ^ d[i3]; 933 i1--; i2--; i3--; 934 } 935 } 936 } 937 938 static int crypt_iv_elephant(struct crypt_config *cc, struct dm_crypt_request *dmreq) 939 { 940 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 941 u8 *es, *ks, *data, *data2, *data_offset; 942 struct skcipher_request *req; 943 struct scatterlist *sg, *sg2, src, dst; 944 DECLARE_CRYPTO_WAIT(wait); 945 int i, r; 946 947 req = skcipher_request_alloc(elephant->tfm, GFP_NOIO); 948 es = kzalloc(16, GFP_NOIO); /* Key for AES */ 949 ks = kzalloc(32, GFP_NOIO); /* Elephant sector key */ 950 951 if (!req || !es || !ks) { 952 r = -ENOMEM; 953 goto out; 954 } 955 956 *(__le64 *)es = cpu_to_le64(dmreq->iv_sector * cc->sector_size); 957 958 /* E(Ks, e(s)) */ 959 sg_init_one(&src, es, 16); 960 sg_init_one(&dst, ks, 16); 961 skcipher_request_set_crypt(req, &src, &dst, 16, NULL); 962 skcipher_request_set_callback(req, 0, crypto_req_done, &wait); 963 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 964 if (r) 965 goto out; 966 967 /* E(Ks, e'(s)) */ 968 es[15] = 0x80; 969 sg_init_one(&dst, &ks[16], 16); 970 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 971 if (r) 972 goto out; 973 974 sg = crypt_get_sg_data(cc, dmreq->sg_out); 975 data = kmap_atomic(sg_page(sg)); 976 data_offset = data + sg->offset; 977 978 /* Cannot modify original bio, copy to sg_out and apply Elephant to it */ 979 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 980 sg2 = crypt_get_sg_data(cc, dmreq->sg_in); 981 data2 = kmap_atomic(sg_page(sg2)); 982 memcpy(data_offset, data2 + sg2->offset, cc->sector_size); 983 kunmap_atomic(data2); 984 } 985 986 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 987 diffuser_disk_to_cpu((u32*)data_offset, cc->sector_size / sizeof(u32)); 988 diffuser_b_decrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 989 diffuser_a_decrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 990 diffuser_cpu_to_disk((__le32*)data_offset, cc->sector_size / sizeof(u32)); 991 } 992 993 for (i = 0; i < (cc->sector_size / 32); i++) 994 crypto_xor(data_offset + i * 32, ks, 32); 995 996 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 997 diffuser_disk_to_cpu((u32*)data_offset, cc->sector_size / sizeof(u32)); 998 diffuser_a_encrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 999 diffuser_b_encrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 1000 diffuser_cpu_to_disk((__le32*)data_offset, cc->sector_size / sizeof(u32)); 1001 } 1002 1003 kunmap_atomic(data); 1004 out: 1005 kfree_sensitive(ks); 1006 kfree_sensitive(es); 1007 skcipher_request_free(req); 1008 return r; 1009 } 1010 1011 static int crypt_iv_elephant_gen(struct crypt_config *cc, u8 *iv, 1012 struct dm_crypt_request *dmreq) 1013 { 1014 int r; 1015 1016 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 1017 r = crypt_iv_elephant(cc, dmreq); 1018 if (r) 1019 return r; 1020 } 1021 1022 return crypt_iv_eboiv_gen(cc, iv, dmreq); 1023 } 1024 1025 static int crypt_iv_elephant_post(struct crypt_config *cc, u8 *iv, 1026 struct dm_crypt_request *dmreq) 1027 { 1028 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 1029 return crypt_iv_elephant(cc, dmreq); 1030 1031 return 0; 1032 } 1033 1034 static int crypt_iv_elephant_init(struct crypt_config *cc) 1035 { 1036 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 1037 int key_offset = cc->key_size - cc->key_extra_size; 1038 1039 return crypto_skcipher_setkey(elephant->tfm, &cc->key[key_offset], cc->key_extra_size); 1040 } 1041 1042 static int crypt_iv_elephant_wipe(struct crypt_config *cc) 1043 { 1044 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 1045 u8 key[ELEPHANT_MAX_KEY_SIZE]; 1046 1047 memset(key, 0, cc->key_extra_size); 1048 return crypto_skcipher_setkey(elephant->tfm, key, cc->key_extra_size); 1049 } 1050 1051 static const struct crypt_iv_operations crypt_iv_plain_ops = { 1052 .generator = crypt_iv_plain_gen 1053 }; 1054 1055 static const struct crypt_iv_operations crypt_iv_plain64_ops = { 1056 .generator = crypt_iv_plain64_gen 1057 }; 1058 1059 static const struct crypt_iv_operations crypt_iv_plain64be_ops = { 1060 .generator = crypt_iv_plain64be_gen 1061 }; 1062 1063 static const struct crypt_iv_operations crypt_iv_essiv_ops = { 1064 .generator = crypt_iv_essiv_gen 1065 }; 1066 1067 static const struct crypt_iv_operations crypt_iv_benbi_ops = { 1068 .ctr = crypt_iv_benbi_ctr, 1069 .dtr = crypt_iv_benbi_dtr, 1070 .generator = crypt_iv_benbi_gen 1071 }; 1072 1073 static const struct crypt_iv_operations crypt_iv_null_ops = { 1074 .generator = crypt_iv_null_gen 1075 }; 1076 1077 static const struct crypt_iv_operations crypt_iv_lmk_ops = { 1078 .ctr = crypt_iv_lmk_ctr, 1079 .dtr = crypt_iv_lmk_dtr, 1080 .init = crypt_iv_lmk_init, 1081 .wipe = crypt_iv_lmk_wipe, 1082 .generator = crypt_iv_lmk_gen, 1083 .post = crypt_iv_lmk_post 1084 }; 1085 1086 static const struct crypt_iv_operations crypt_iv_tcw_ops = { 1087 .ctr = crypt_iv_tcw_ctr, 1088 .dtr = crypt_iv_tcw_dtr, 1089 .init = crypt_iv_tcw_init, 1090 .wipe = crypt_iv_tcw_wipe, 1091 .generator = crypt_iv_tcw_gen, 1092 .post = crypt_iv_tcw_post 1093 }; 1094 1095 static const struct crypt_iv_operations crypt_iv_random_ops = { 1096 .generator = crypt_iv_random_gen 1097 }; 1098 1099 static const struct crypt_iv_operations crypt_iv_eboiv_ops = { 1100 .ctr = crypt_iv_eboiv_ctr, 1101 .generator = crypt_iv_eboiv_gen 1102 }; 1103 1104 static const struct crypt_iv_operations crypt_iv_elephant_ops = { 1105 .ctr = crypt_iv_elephant_ctr, 1106 .dtr = crypt_iv_elephant_dtr, 1107 .init = crypt_iv_elephant_init, 1108 .wipe = crypt_iv_elephant_wipe, 1109 .generator = crypt_iv_elephant_gen, 1110 .post = crypt_iv_elephant_post 1111 }; 1112 1113 /* 1114 * Integrity extensions 1115 */ 1116 static bool crypt_integrity_aead(struct crypt_config *cc) 1117 { 1118 return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 1119 } 1120 1121 static bool crypt_integrity_hmac(struct crypt_config *cc) 1122 { 1123 return crypt_integrity_aead(cc) && cc->key_mac_size; 1124 } 1125 1126 /* Get sg containing data */ 1127 static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 1128 struct scatterlist *sg) 1129 { 1130 if (unlikely(crypt_integrity_aead(cc))) 1131 return &sg[2]; 1132 1133 return sg; 1134 } 1135 1136 static int dm_crypt_integrity_io_alloc(struct dm_crypt_io *io, struct bio *bio) 1137 { 1138 struct bio_integrity_payload *bip; 1139 unsigned int tag_len; 1140 int ret; 1141 1142 if (!bio_sectors(bio) || !io->cc->on_disk_tag_size) 1143 return 0; 1144 1145 bip = bio_integrity_alloc(bio, GFP_NOIO, 1); 1146 if (IS_ERR(bip)) 1147 return PTR_ERR(bip); 1148 1149 tag_len = io->cc->on_disk_tag_size * (bio_sectors(bio) >> io->cc->sector_shift); 1150 1151 bip->bip_iter.bi_size = tag_len; 1152 bip->bip_iter.bi_sector = io->cc->start + io->sector; 1153 1154 ret = bio_integrity_add_page(bio, virt_to_page(io->integrity_metadata), 1155 tag_len, offset_in_page(io->integrity_metadata)); 1156 if (unlikely(ret != tag_len)) 1157 return -ENOMEM; 1158 1159 return 0; 1160 } 1161 1162 static int crypt_integrity_ctr(struct crypt_config *cc, struct dm_target *ti) 1163 { 1164 #ifdef CONFIG_BLK_DEV_INTEGRITY 1165 struct blk_integrity *bi = blk_get_integrity(cc->dev->bdev->bd_disk); 1166 struct mapped_device *md = dm_table_get_md(ti->table); 1167 1168 /* From now we require underlying device with our integrity profile */ 1169 if (!bi || strcasecmp(bi->profile->name, "DM-DIF-EXT-TAG")) { 1170 ti->error = "Integrity profile not supported."; 1171 return -EINVAL; 1172 } 1173 1174 if (bi->tag_size != cc->on_disk_tag_size || 1175 bi->tuple_size != cc->on_disk_tag_size) { 1176 ti->error = "Integrity profile tag size mismatch."; 1177 return -EINVAL; 1178 } 1179 if (1 << bi->interval_exp != cc->sector_size) { 1180 ti->error = "Integrity profile sector size mismatch."; 1181 return -EINVAL; 1182 } 1183 1184 if (crypt_integrity_aead(cc)) { 1185 cc->integrity_tag_size = cc->on_disk_tag_size - cc->integrity_iv_size; 1186 DMDEBUG("%s: Integrity AEAD, tag size %u, IV size %u.", dm_device_name(md), 1187 cc->integrity_tag_size, cc->integrity_iv_size); 1188 1189 if (crypto_aead_setauthsize(any_tfm_aead(cc), cc->integrity_tag_size)) { 1190 ti->error = "Integrity AEAD auth tag size is not supported."; 1191 return -EINVAL; 1192 } 1193 } else if (cc->integrity_iv_size) 1194 DMDEBUG("%s: Additional per-sector space %u bytes for IV.", dm_device_name(md), 1195 cc->integrity_iv_size); 1196 1197 if ((cc->integrity_tag_size + cc->integrity_iv_size) != bi->tag_size) { 1198 ti->error = "Not enough space for integrity tag in the profile."; 1199 return -EINVAL; 1200 } 1201 1202 return 0; 1203 #else 1204 ti->error = "Integrity profile not supported."; 1205 return -EINVAL; 1206 #endif 1207 } 1208 1209 static void crypt_convert_init(struct crypt_config *cc, 1210 struct convert_context *ctx, 1211 struct bio *bio_out, struct bio *bio_in, 1212 sector_t sector) 1213 { 1214 ctx->bio_in = bio_in; 1215 ctx->bio_out = bio_out; 1216 if (bio_in) 1217 ctx->iter_in = bio_in->bi_iter; 1218 if (bio_out) 1219 ctx->iter_out = bio_out->bi_iter; 1220 ctx->cc_sector = sector + cc->iv_offset; 1221 init_completion(&ctx->restart); 1222 } 1223 1224 static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc, 1225 void *req) 1226 { 1227 return (struct dm_crypt_request *)((char *)req + cc->dmreq_start); 1228 } 1229 1230 static void *req_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq) 1231 { 1232 return (void *)((char *)dmreq - cc->dmreq_start); 1233 } 1234 1235 static u8 *iv_of_dmreq(struct crypt_config *cc, 1236 struct dm_crypt_request *dmreq) 1237 { 1238 if (crypt_integrity_aead(cc)) 1239 return (u8 *)ALIGN((unsigned long)(dmreq + 1), 1240 crypto_aead_alignmask(any_tfm_aead(cc)) + 1); 1241 else 1242 return (u8 *)ALIGN((unsigned long)(dmreq + 1), 1243 crypto_skcipher_alignmask(any_tfm(cc)) + 1); 1244 } 1245 1246 static u8 *org_iv_of_dmreq(struct crypt_config *cc, 1247 struct dm_crypt_request *dmreq) 1248 { 1249 return iv_of_dmreq(cc, dmreq) + cc->iv_size; 1250 } 1251 1252 static __le64 *org_sector_of_dmreq(struct crypt_config *cc, 1253 struct dm_crypt_request *dmreq) 1254 { 1255 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + cc->iv_size; 1256 return (__le64 *) ptr; 1257 } 1258 1259 static unsigned int *org_tag_of_dmreq(struct crypt_config *cc, 1260 struct dm_crypt_request *dmreq) 1261 { 1262 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + 1263 cc->iv_size + sizeof(uint64_t); 1264 return (unsigned int*)ptr; 1265 } 1266 1267 static void *tag_from_dmreq(struct crypt_config *cc, 1268 struct dm_crypt_request *dmreq) 1269 { 1270 struct convert_context *ctx = dmreq->ctx; 1271 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 1272 1273 return &io->integrity_metadata[*org_tag_of_dmreq(cc, dmreq) * 1274 cc->on_disk_tag_size]; 1275 } 1276 1277 static void *iv_tag_from_dmreq(struct crypt_config *cc, 1278 struct dm_crypt_request *dmreq) 1279 { 1280 return tag_from_dmreq(cc, dmreq) + cc->integrity_tag_size; 1281 } 1282 1283 static int crypt_convert_block_aead(struct crypt_config *cc, 1284 struct convert_context *ctx, 1285 struct aead_request *req, 1286 unsigned int tag_offset) 1287 { 1288 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1289 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1290 struct dm_crypt_request *dmreq; 1291 u8 *iv, *org_iv, *tag_iv, *tag; 1292 __le64 *sector; 1293 int r = 0; 1294 1295 BUG_ON(cc->integrity_iv_size && cc->integrity_iv_size != cc->iv_size); 1296 1297 /* Reject unexpected unaligned bio. */ 1298 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1299 return -EIO; 1300 1301 dmreq = dmreq_of_req(cc, req); 1302 dmreq->iv_sector = ctx->cc_sector; 1303 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1304 dmreq->iv_sector >>= cc->sector_shift; 1305 dmreq->ctx = ctx; 1306 1307 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1308 1309 sector = org_sector_of_dmreq(cc, dmreq); 1310 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1311 1312 iv = iv_of_dmreq(cc, dmreq); 1313 org_iv = org_iv_of_dmreq(cc, dmreq); 1314 tag = tag_from_dmreq(cc, dmreq); 1315 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1316 1317 /* AEAD request: 1318 * |----- AAD -------|------ DATA -------|-- AUTH TAG --| 1319 * | (authenticated) | (auth+encryption) | | 1320 * | sector_LE | IV | sector in/out | tag in/out | 1321 */ 1322 sg_init_table(dmreq->sg_in, 4); 1323 sg_set_buf(&dmreq->sg_in[0], sector, sizeof(uint64_t)); 1324 sg_set_buf(&dmreq->sg_in[1], org_iv, cc->iv_size); 1325 sg_set_page(&dmreq->sg_in[2], bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1326 sg_set_buf(&dmreq->sg_in[3], tag, cc->integrity_tag_size); 1327 1328 sg_init_table(dmreq->sg_out, 4); 1329 sg_set_buf(&dmreq->sg_out[0], sector, sizeof(uint64_t)); 1330 sg_set_buf(&dmreq->sg_out[1], org_iv, cc->iv_size); 1331 sg_set_page(&dmreq->sg_out[2], bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1332 sg_set_buf(&dmreq->sg_out[3], tag, cc->integrity_tag_size); 1333 1334 if (cc->iv_gen_ops) { 1335 /* For READs use IV stored in integrity metadata */ 1336 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1337 memcpy(org_iv, tag_iv, cc->iv_size); 1338 } else { 1339 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1340 if (r < 0) 1341 return r; 1342 /* Store generated IV in integrity metadata */ 1343 if (cc->integrity_iv_size) 1344 memcpy(tag_iv, org_iv, cc->iv_size); 1345 } 1346 /* Working copy of IV, to be modified in crypto API */ 1347 memcpy(iv, org_iv, cc->iv_size); 1348 } 1349 1350 aead_request_set_ad(req, sizeof(uint64_t) + cc->iv_size); 1351 if (bio_data_dir(ctx->bio_in) == WRITE) { 1352 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out, 1353 cc->sector_size, iv); 1354 r = crypto_aead_encrypt(req); 1355 if (cc->integrity_tag_size + cc->integrity_iv_size != cc->on_disk_tag_size) 1356 memset(tag + cc->integrity_tag_size + cc->integrity_iv_size, 0, 1357 cc->on_disk_tag_size - (cc->integrity_tag_size + cc->integrity_iv_size)); 1358 } else { 1359 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out, 1360 cc->sector_size + cc->integrity_tag_size, iv); 1361 r = crypto_aead_decrypt(req); 1362 } 1363 1364 if (r == -EBADMSG) { 1365 char b[BDEVNAME_SIZE]; 1366 DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu", bio_devname(ctx->bio_in, b), 1367 (unsigned long long)le64_to_cpu(*sector)); 1368 } 1369 1370 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1371 r = cc->iv_gen_ops->post(cc, org_iv, dmreq); 1372 1373 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1374 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1375 1376 return r; 1377 } 1378 1379 static int crypt_convert_block_skcipher(struct crypt_config *cc, 1380 struct convert_context *ctx, 1381 struct skcipher_request *req, 1382 unsigned int tag_offset) 1383 { 1384 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1385 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1386 struct scatterlist *sg_in, *sg_out; 1387 struct dm_crypt_request *dmreq; 1388 u8 *iv, *org_iv, *tag_iv; 1389 __le64 *sector; 1390 int r = 0; 1391 1392 /* Reject unexpected unaligned bio. */ 1393 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1394 return -EIO; 1395 1396 dmreq = dmreq_of_req(cc, req); 1397 dmreq->iv_sector = ctx->cc_sector; 1398 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1399 dmreq->iv_sector >>= cc->sector_shift; 1400 dmreq->ctx = ctx; 1401 1402 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1403 1404 iv = iv_of_dmreq(cc, dmreq); 1405 org_iv = org_iv_of_dmreq(cc, dmreq); 1406 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1407 1408 sector = org_sector_of_dmreq(cc, dmreq); 1409 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1410 1411 /* For skcipher we use only the first sg item */ 1412 sg_in = &dmreq->sg_in[0]; 1413 sg_out = &dmreq->sg_out[0]; 1414 1415 sg_init_table(sg_in, 1); 1416 sg_set_page(sg_in, bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1417 1418 sg_init_table(sg_out, 1); 1419 sg_set_page(sg_out, bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1420 1421 if (cc->iv_gen_ops) { 1422 /* For READs use IV stored in integrity metadata */ 1423 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1424 memcpy(org_iv, tag_iv, cc->integrity_iv_size); 1425 } else { 1426 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1427 if (r < 0) 1428 return r; 1429 /* Data can be already preprocessed in generator */ 1430 if (test_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags)) 1431 sg_in = sg_out; 1432 /* Store generated IV in integrity metadata */ 1433 if (cc->integrity_iv_size) 1434 memcpy(tag_iv, org_iv, cc->integrity_iv_size); 1435 } 1436 /* Working copy of IV, to be modified in crypto API */ 1437 memcpy(iv, org_iv, cc->iv_size); 1438 } 1439 1440 skcipher_request_set_crypt(req, sg_in, sg_out, cc->sector_size, iv); 1441 1442 if (bio_data_dir(ctx->bio_in) == WRITE) 1443 r = crypto_skcipher_encrypt(req); 1444 else 1445 r = crypto_skcipher_decrypt(req); 1446 1447 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1448 r = cc->iv_gen_ops->post(cc, org_iv, dmreq); 1449 1450 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1451 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1452 1453 return r; 1454 } 1455 1456 static void kcryptd_async_done(struct crypto_async_request *async_req, 1457 int error); 1458 1459 static int crypt_alloc_req_skcipher(struct crypt_config *cc, 1460 struct convert_context *ctx) 1461 { 1462 unsigned key_index = ctx->cc_sector & (cc->tfms_count - 1); 1463 1464 if (!ctx->r.req) { 1465 ctx->r.req = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1466 if (!ctx->r.req) 1467 return -ENOMEM; 1468 } 1469 1470 skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]); 1471 1472 /* 1473 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1474 * requests if driver request queue is full. 1475 */ 1476 skcipher_request_set_callback(ctx->r.req, 1477 CRYPTO_TFM_REQ_MAY_BACKLOG, 1478 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req)); 1479 1480 return 0; 1481 } 1482 1483 static int crypt_alloc_req_aead(struct crypt_config *cc, 1484 struct convert_context *ctx) 1485 { 1486 if (!ctx->r.req_aead) { 1487 ctx->r.req_aead = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1488 if (!ctx->r.req_aead) 1489 return -ENOMEM; 1490 } 1491 1492 aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]); 1493 1494 /* 1495 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1496 * requests if driver request queue is full. 1497 */ 1498 aead_request_set_callback(ctx->r.req_aead, 1499 CRYPTO_TFM_REQ_MAY_BACKLOG, 1500 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead)); 1501 1502 return 0; 1503 } 1504 1505 static int crypt_alloc_req(struct crypt_config *cc, 1506 struct convert_context *ctx) 1507 { 1508 if (crypt_integrity_aead(cc)) 1509 return crypt_alloc_req_aead(cc, ctx); 1510 else 1511 return crypt_alloc_req_skcipher(cc, ctx); 1512 } 1513 1514 static void crypt_free_req_skcipher(struct crypt_config *cc, 1515 struct skcipher_request *req, struct bio *base_bio) 1516 { 1517 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1518 1519 if ((struct skcipher_request *)(io + 1) != req) 1520 mempool_free(req, &cc->req_pool); 1521 } 1522 1523 static void crypt_free_req_aead(struct crypt_config *cc, 1524 struct aead_request *req, struct bio *base_bio) 1525 { 1526 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1527 1528 if ((struct aead_request *)(io + 1) != req) 1529 mempool_free(req, &cc->req_pool); 1530 } 1531 1532 static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio) 1533 { 1534 if (crypt_integrity_aead(cc)) 1535 crypt_free_req_aead(cc, req, base_bio); 1536 else 1537 crypt_free_req_skcipher(cc, req, base_bio); 1538 } 1539 1540 /* 1541 * Encrypt / decrypt data from one bio to another one (can be the same one) 1542 */ 1543 static blk_status_t crypt_convert(struct crypt_config *cc, 1544 struct convert_context *ctx, bool atomic, bool reset_pending) 1545 { 1546 unsigned int tag_offset = 0; 1547 unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT; 1548 int r; 1549 1550 /* 1551 * if reset_pending is set we are dealing with the bio for the first time, 1552 * else we're continuing to work on the previous bio, so don't mess with 1553 * the cc_pending counter 1554 */ 1555 if (reset_pending) 1556 atomic_set(&ctx->cc_pending, 1); 1557 1558 while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) { 1559 1560 r = crypt_alloc_req(cc, ctx); 1561 if (r) { 1562 complete(&ctx->restart); 1563 return BLK_STS_DEV_RESOURCE; 1564 } 1565 1566 atomic_inc(&ctx->cc_pending); 1567 1568 if (crypt_integrity_aead(cc)) 1569 r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, tag_offset); 1570 else 1571 r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, tag_offset); 1572 1573 switch (r) { 1574 /* 1575 * The request was queued by a crypto driver 1576 * but the driver request queue is full, let's wait. 1577 */ 1578 case -EBUSY: 1579 if (in_interrupt()) { 1580 if (try_wait_for_completion(&ctx->restart)) { 1581 /* 1582 * we don't have to block to wait for completion, 1583 * so proceed 1584 */ 1585 } else { 1586 /* 1587 * we can't wait for completion without blocking 1588 * exit and continue processing in a workqueue 1589 */ 1590 ctx->r.req = NULL; 1591 ctx->cc_sector += sector_step; 1592 tag_offset++; 1593 return BLK_STS_DEV_RESOURCE; 1594 } 1595 } else { 1596 wait_for_completion(&ctx->restart); 1597 } 1598 reinit_completion(&ctx->restart); 1599 fallthrough; 1600 /* 1601 * The request is queued and processed asynchronously, 1602 * completion function kcryptd_async_done() will be called. 1603 */ 1604 case -EINPROGRESS: 1605 ctx->r.req = NULL; 1606 ctx->cc_sector += sector_step; 1607 tag_offset++; 1608 continue; 1609 /* 1610 * The request was already processed (synchronously). 1611 */ 1612 case 0: 1613 atomic_dec(&ctx->cc_pending); 1614 ctx->cc_sector += sector_step; 1615 tag_offset++; 1616 if (!atomic) 1617 cond_resched(); 1618 continue; 1619 /* 1620 * There was a data integrity error. 1621 */ 1622 case -EBADMSG: 1623 atomic_dec(&ctx->cc_pending); 1624 return BLK_STS_PROTECTION; 1625 /* 1626 * There was an error while processing the request. 1627 */ 1628 default: 1629 atomic_dec(&ctx->cc_pending); 1630 return BLK_STS_IOERR; 1631 } 1632 } 1633 1634 return 0; 1635 } 1636 1637 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone); 1638 1639 /* 1640 * Generate a new unfragmented bio with the given size 1641 * This should never violate the device limitations (but only because 1642 * max_segment_size is being constrained to PAGE_SIZE). 1643 * 1644 * This function may be called concurrently. If we allocate from the mempool 1645 * concurrently, there is a possibility of deadlock. For example, if we have 1646 * mempool of 256 pages, two processes, each wanting 256, pages allocate from 1647 * the mempool concurrently, it may deadlock in a situation where both processes 1648 * have allocated 128 pages and the mempool is exhausted. 1649 * 1650 * In order to avoid this scenario we allocate the pages under a mutex. 1651 * 1652 * In order to not degrade performance with excessive locking, we try 1653 * non-blocking allocations without a mutex first but on failure we fallback 1654 * to blocking allocations with a mutex. 1655 */ 1656 static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size) 1657 { 1658 struct crypt_config *cc = io->cc; 1659 struct bio *clone; 1660 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; 1661 gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM; 1662 unsigned i, len, remaining_size; 1663 struct page *page; 1664 1665 retry: 1666 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1667 mutex_lock(&cc->bio_alloc_lock); 1668 1669 clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, &cc->bs); 1670 if (!clone) 1671 goto out; 1672 1673 clone_init(io, clone); 1674 1675 remaining_size = size; 1676 1677 for (i = 0; i < nr_iovecs; i++) { 1678 page = mempool_alloc(&cc->page_pool, gfp_mask); 1679 if (!page) { 1680 crypt_free_buffer_pages(cc, clone); 1681 bio_put(clone); 1682 gfp_mask |= __GFP_DIRECT_RECLAIM; 1683 goto retry; 1684 } 1685 1686 len = (remaining_size > PAGE_SIZE) ? PAGE_SIZE : remaining_size; 1687 1688 bio_add_page(clone, page, len, 0); 1689 1690 remaining_size -= len; 1691 } 1692 1693 /* Allocate space for integrity tags */ 1694 if (dm_crypt_integrity_io_alloc(io, clone)) { 1695 crypt_free_buffer_pages(cc, clone); 1696 bio_put(clone); 1697 clone = NULL; 1698 } 1699 out: 1700 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1701 mutex_unlock(&cc->bio_alloc_lock); 1702 1703 return clone; 1704 } 1705 1706 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) 1707 { 1708 struct bio_vec *bv; 1709 struct bvec_iter_all iter_all; 1710 1711 bio_for_each_segment_all(bv, clone, iter_all) { 1712 BUG_ON(!bv->bv_page); 1713 mempool_free(bv->bv_page, &cc->page_pool); 1714 } 1715 } 1716 1717 static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc, 1718 struct bio *bio, sector_t sector) 1719 { 1720 io->cc = cc; 1721 io->base_bio = bio; 1722 io->sector = sector; 1723 io->error = 0; 1724 io->ctx.r.req = NULL; 1725 io->integrity_metadata = NULL; 1726 io->integrity_metadata_from_pool = false; 1727 atomic_set(&io->io_pending, 0); 1728 } 1729 1730 static void crypt_inc_pending(struct dm_crypt_io *io) 1731 { 1732 atomic_inc(&io->io_pending); 1733 } 1734 1735 static void kcryptd_io_bio_endio(struct work_struct *work) 1736 { 1737 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 1738 bio_endio(io->base_bio); 1739 } 1740 1741 /* 1742 * One of the bios was finished. Check for completion of 1743 * the whole request and correctly clean up the buffer. 1744 */ 1745 static void crypt_dec_pending(struct dm_crypt_io *io) 1746 { 1747 struct crypt_config *cc = io->cc; 1748 struct bio *base_bio = io->base_bio; 1749 blk_status_t error = io->error; 1750 1751 if (!atomic_dec_and_test(&io->io_pending)) 1752 return; 1753 1754 if (io->ctx.r.req) 1755 crypt_free_req(cc, io->ctx.r.req, base_bio); 1756 1757 if (unlikely(io->integrity_metadata_from_pool)) 1758 mempool_free(io->integrity_metadata, &io->cc->tag_pool); 1759 else 1760 kfree(io->integrity_metadata); 1761 1762 base_bio->bi_status = error; 1763 1764 /* 1765 * If we are running this function from our tasklet, 1766 * we can't call bio_endio() here, because it will call 1767 * clone_endio() from dm.c, which in turn will 1768 * free the current struct dm_crypt_io structure with 1769 * our tasklet. In this case we need to delay bio_endio() 1770 * execution to after the tasklet is done and dequeued. 1771 */ 1772 if (tasklet_trylock(&io->tasklet)) { 1773 tasklet_unlock(&io->tasklet); 1774 bio_endio(base_bio); 1775 return; 1776 } 1777 1778 INIT_WORK(&io->work, kcryptd_io_bio_endio); 1779 queue_work(cc->io_queue, &io->work); 1780 } 1781 1782 /* 1783 * kcryptd/kcryptd_io: 1784 * 1785 * Needed because it would be very unwise to do decryption in an 1786 * interrupt context. 1787 * 1788 * kcryptd performs the actual encryption or decryption. 1789 * 1790 * kcryptd_io performs the IO submission. 1791 * 1792 * They must be separated as otherwise the final stages could be 1793 * starved by new requests which can block in the first stages due 1794 * to memory allocation. 1795 * 1796 * The work is done per CPU global for all dm-crypt instances. 1797 * They should not depend on each other and do not block. 1798 */ 1799 static void crypt_endio(struct bio *clone) 1800 { 1801 struct dm_crypt_io *io = clone->bi_private; 1802 struct crypt_config *cc = io->cc; 1803 unsigned rw = bio_data_dir(clone); 1804 blk_status_t error; 1805 1806 /* 1807 * free the processed pages 1808 */ 1809 if (rw == WRITE) 1810 crypt_free_buffer_pages(cc, clone); 1811 1812 error = clone->bi_status; 1813 bio_put(clone); 1814 1815 if (rw == READ && !error) { 1816 kcryptd_queue_crypt(io); 1817 return; 1818 } 1819 1820 if (unlikely(error)) 1821 io->error = error; 1822 1823 crypt_dec_pending(io); 1824 } 1825 1826 static void clone_init(struct dm_crypt_io *io, struct bio *clone) 1827 { 1828 struct crypt_config *cc = io->cc; 1829 1830 clone->bi_private = io; 1831 clone->bi_end_io = crypt_endio; 1832 bio_set_dev(clone, cc->dev->bdev); 1833 clone->bi_opf = io->base_bio->bi_opf; 1834 } 1835 1836 static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp) 1837 { 1838 struct crypt_config *cc = io->cc; 1839 struct bio *clone; 1840 1841 /* 1842 * We need the original biovec array in order to decrypt 1843 * the whole bio data *afterwards* -- thanks to immutable 1844 * biovecs we don't need to worry about the block layer 1845 * modifying the biovec array; so leverage bio_clone_fast(). 1846 */ 1847 clone = bio_clone_fast(io->base_bio, gfp, &cc->bs); 1848 if (!clone) 1849 return 1; 1850 1851 crypt_inc_pending(io); 1852 1853 clone_init(io, clone); 1854 clone->bi_iter.bi_sector = cc->start + io->sector; 1855 1856 if (dm_crypt_integrity_io_alloc(io, clone)) { 1857 crypt_dec_pending(io); 1858 bio_put(clone); 1859 return 1; 1860 } 1861 1862 submit_bio_noacct(clone); 1863 return 0; 1864 } 1865 1866 static void kcryptd_io_read_work(struct work_struct *work) 1867 { 1868 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 1869 1870 crypt_inc_pending(io); 1871 if (kcryptd_io_read(io, GFP_NOIO)) 1872 io->error = BLK_STS_RESOURCE; 1873 crypt_dec_pending(io); 1874 } 1875 1876 static void kcryptd_queue_read(struct dm_crypt_io *io) 1877 { 1878 struct crypt_config *cc = io->cc; 1879 1880 INIT_WORK(&io->work, kcryptd_io_read_work); 1881 queue_work(cc->io_queue, &io->work); 1882 } 1883 1884 static void kcryptd_io_write(struct dm_crypt_io *io) 1885 { 1886 struct bio *clone = io->ctx.bio_out; 1887 1888 submit_bio_noacct(clone); 1889 } 1890 1891 #define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node) 1892 1893 static int dmcrypt_write(void *data) 1894 { 1895 struct crypt_config *cc = data; 1896 struct dm_crypt_io *io; 1897 1898 while (1) { 1899 struct rb_root write_tree; 1900 struct blk_plug plug; 1901 1902 spin_lock_irq(&cc->write_thread_lock); 1903 continue_locked: 1904 1905 if (!RB_EMPTY_ROOT(&cc->write_tree)) 1906 goto pop_from_list; 1907 1908 set_current_state(TASK_INTERRUPTIBLE); 1909 1910 spin_unlock_irq(&cc->write_thread_lock); 1911 1912 if (unlikely(kthread_should_stop())) { 1913 set_current_state(TASK_RUNNING); 1914 break; 1915 } 1916 1917 schedule(); 1918 1919 set_current_state(TASK_RUNNING); 1920 spin_lock_irq(&cc->write_thread_lock); 1921 goto continue_locked; 1922 1923 pop_from_list: 1924 write_tree = cc->write_tree; 1925 cc->write_tree = RB_ROOT; 1926 spin_unlock_irq(&cc->write_thread_lock); 1927 1928 BUG_ON(rb_parent(write_tree.rb_node)); 1929 1930 /* 1931 * Note: we cannot walk the tree here with rb_next because 1932 * the structures may be freed when kcryptd_io_write is called. 1933 */ 1934 blk_start_plug(&plug); 1935 do { 1936 io = crypt_io_from_node(rb_first(&write_tree)); 1937 rb_erase(&io->rb_node, &write_tree); 1938 kcryptd_io_write(io); 1939 } while (!RB_EMPTY_ROOT(&write_tree)); 1940 blk_finish_plug(&plug); 1941 } 1942 return 0; 1943 } 1944 1945 static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async) 1946 { 1947 struct bio *clone = io->ctx.bio_out; 1948 struct crypt_config *cc = io->cc; 1949 unsigned long flags; 1950 sector_t sector; 1951 struct rb_node **rbp, *parent; 1952 1953 if (unlikely(io->error)) { 1954 crypt_free_buffer_pages(cc, clone); 1955 bio_put(clone); 1956 crypt_dec_pending(io); 1957 return; 1958 } 1959 1960 /* crypt_convert should have filled the clone bio */ 1961 BUG_ON(io->ctx.iter_out.bi_size); 1962 1963 clone->bi_iter.bi_sector = cc->start + io->sector; 1964 1965 if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) || 1966 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) { 1967 submit_bio_noacct(clone); 1968 return; 1969 } 1970 1971 spin_lock_irqsave(&cc->write_thread_lock, flags); 1972 if (RB_EMPTY_ROOT(&cc->write_tree)) 1973 wake_up_process(cc->write_thread); 1974 rbp = &cc->write_tree.rb_node; 1975 parent = NULL; 1976 sector = io->sector; 1977 while (*rbp) { 1978 parent = *rbp; 1979 if (sector < crypt_io_from_node(parent)->sector) 1980 rbp = &(*rbp)->rb_left; 1981 else 1982 rbp = &(*rbp)->rb_right; 1983 } 1984 rb_link_node(&io->rb_node, parent, rbp); 1985 rb_insert_color(&io->rb_node, &cc->write_tree); 1986 spin_unlock_irqrestore(&cc->write_thread_lock, flags); 1987 } 1988 1989 static bool kcryptd_crypt_write_inline(struct crypt_config *cc, 1990 struct convert_context *ctx) 1991 1992 { 1993 if (!test_bit(DM_CRYPT_WRITE_INLINE, &cc->flags)) 1994 return false; 1995 1996 /* 1997 * Note: zone append writes (REQ_OP_ZONE_APPEND) do not have ordering 1998 * constraints so they do not need to be issued inline by 1999 * kcryptd_crypt_write_convert(). 2000 */ 2001 switch (bio_op(ctx->bio_in)) { 2002 case REQ_OP_WRITE: 2003 case REQ_OP_WRITE_SAME: 2004 case REQ_OP_WRITE_ZEROES: 2005 return true; 2006 default: 2007 return false; 2008 } 2009 } 2010 2011 static void kcryptd_crypt_write_continue(struct work_struct *work) 2012 { 2013 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2014 struct crypt_config *cc = io->cc; 2015 struct convert_context *ctx = &io->ctx; 2016 int crypt_finished; 2017 sector_t sector = io->sector; 2018 blk_status_t r; 2019 2020 wait_for_completion(&ctx->restart); 2021 reinit_completion(&ctx->restart); 2022 2023 r = crypt_convert(cc, &io->ctx, true, false); 2024 if (r) 2025 io->error = r; 2026 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2027 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2028 /* Wait for completion signaled by kcryptd_async_done() */ 2029 wait_for_completion(&ctx->restart); 2030 crypt_finished = 1; 2031 } 2032 2033 /* Encryption was already finished, submit io now */ 2034 if (crypt_finished) { 2035 kcryptd_crypt_write_io_submit(io, 0); 2036 io->sector = sector; 2037 } 2038 2039 crypt_dec_pending(io); 2040 } 2041 2042 static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) 2043 { 2044 struct crypt_config *cc = io->cc; 2045 struct convert_context *ctx = &io->ctx; 2046 struct bio *clone; 2047 int crypt_finished; 2048 sector_t sector = io->sector; 2049 blk_status_t r; 2050 2051 /* 2052 * Prevent io from disappearing until this function completes. 2053 */ 2054 crypt_inc_pending(io); 2055 crypt_convert_init(cc, ctx, NULL, io->base_bio, sector); 2056 2057 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size); 2058 if (unlikely(!clone)) { 2059 io->error = BLK_STS_IOERR; 2060 goto dec; 2061 } 2062 2063 io->ctx.bio_out = clone; 2064 io->ctx.iter_out = clone->bi_iter; 2065 2066 sector += bio_sectors(clone); 2067 2068 crypt_inc_pending(io); 2069 r = crypt_convert(cc, ctx, 2070 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags), true); 2071 /* 2072 * Crypto API backlogged the request, because its queue was full 2073 * and we're in softirq context, so continue from a workqueue 2074 * (TODO: is it actually possible to be in softirq in the write path?) 2075 */ 2076 if (r == BLK_STS_DEV_RESOURCE) { 2077 INIT_WORK(&io->work, kcryptd_crypt_write_continue); 2078 queue_work(cc->crypt_queue, &io->work); 2079 return; 2080 } 2081 if (r) 2082 io->error = r; 2083 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2084 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2085 /* Wait for completion signaled by kcryptd_async_done() */ 2086 wait_for_completion(&ctx->restart); 2087 crypt_finished = 1; 2088 } 2089 2090 /* Encryption was already finished, submit io now */ 2091 if (crypt_finished) { 2092 kcryptd_crypt_write_io_submit(io, 0); 2093 io->sector = sector; 2094 } 2095 2096 dec: 2097 crypt_dec_pending(io); 2098 } 2099 2100 static void kcryptd_crypt_read_done(struct dm_crypt_io *io) 2101 { 2102 crypt_dec_pending(io); 2103 } 2104 2105 static void kcryptd_crypt_read_continue(struct work_struct *work) 2106 { 2107 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2108 struct crypt_config *cc = io->cc; 2109 blk_status_t r; 2110 2111 wait_for_completion(&io->ctx.restart); 2112 reinit_completion(&io->ctx.restart); 2113 2114 r = crypt_convert(cc, &io->ctx, true, false); 2115 if (r) 2116 io->error = r; 2117 2118 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2119 kcryptd_crypt_read_done(io); 2120 2121 crypt_dec_pending(io); 2122 } 2123 2124 static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) 2125 { 2126 struct crypt_config *cc = io->cc; 2127 blk_status_t r; 2128 2129 crypt_inc_pending(io); 2130 2131 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, 2132 io->sector); 2133 2134 r = crypt_convert(cc, &io->ctx, 2135 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true); 2136 /* 2137 * Crypto API backlogged the request, because its queue was full 2138 * and we're in softirq context, so continue from a workqueue 2139 */ 2140 if (r == BLK_STS_DEV_RESOURCE) { 2141 INIT_WORK(&io->work, kcryptd_crypt_read_continue); 2142 queue_work(cc->crypt_queue, &io->work); 2143 return; 2144 } 2145 if (r) 2146 io->error = r; 2147 2148 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2149 kcryptd_crypt_read_done(io); 2150 2151 crypt_dec_pending(io); 2152 } 2153 2154 static void kcryptd_async_done(struct crypto_async_request *async_req, 2155 int error) 2156 { 2157 struct dm_crypt_request *dmreq = async_req->data; 2158 struct convert_context *ctx = dmreq->ctx; 2159 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 2160 struct crypt_config *cc = io->cc; 2161 2162 /* 2163 * A request from crypto driver backlog is going to be processed now, 2164 * finish the completion and continue in crypt_convert(). 2165 * (Callback will be called for the second time for this request.) 2166 */ 2167 if (error == -EINPROGRESS) { 2168 complete(&ctx->restart); 2169 return; 2170 } 2171 2172 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post) 2173 error = cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq); 2174 2175 if (error == -EBADMSG) { 2176 char b[BDEVNAME_SIZE]; 2177 DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu", bio_devname(ctx->bio_in, b), 2178 (unsigned long long)le64_to_cpu(*org_sector_of_dmreq(cc, dmreq))); 2179 io->error = BLK_STS_PROTECTION; 2180 } else if (error < 0) 2181 io->error = BLK_STS_IOERR; 2182 2183 crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio); 2184 2185 if (!atomic_dec_and_test(&ctx->cc_pending)) 2186 return; 2187 2188 /* 2189 * The request is fully completed: for inline writes, let 2190 * kcryptd_crypt_write_convert() do the IO submission. 2191 */ 2192 if (bio_data_dir(io->base_bio) == READ) { 2193 kcryptd_crypt_read_done(io); 2194 return; 2195 } 2196 2197 if (kcryptd_crypt_write_inline(cc, ctx)) { 2198 complete(&ctx->restart); 2199 return; 2200 } 2201 2202 kcryptd_crypt_write_io_submit(io, 1); 2203 } 2204 2205 static void kcryptd_crypt(struct work_struct *work) 2206 { 2207 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2208 2209 if (bio_data_dir(io->base_bio) == READ) 2210 kcryptd_crypt_read_convert(io); 2211 else 2212 kcryptd_crypt_write_convert(io); 2213 } 2214 2215 static void kcryptd_crypt_tasklet(unsigned long work) 2216 { 2217 kcryptd_crypt((struct work_struct *)work); 2218 } 2219 2220 static void kcryptd_queue_crypt(struct dm_crypt_io *io) 2221 { 2222 struct crypt_config *cc = io->cc; 2223 2224 if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) || 2225 (bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) { 2226 /* 2227 * in_hardirq(): Crypto API's skcipher_walk_first() refuses to work in hard IRQ context. 2228 * irqs_disabled(): the kernel may run some IO completion from the idle thread, but 2229 * it is being executed with irqs disabled. 2230 */ 2231 if (in_hardirq() || irqs_disabled()) { 2232 tasklet_init(&io->tasklet, kcryptd_crypt_tasklet, (unsigned long)&io->work); 2233 tasklet_schedule(&io->tasklet); 2234 return; 2235 } 2236 2237 kcryptd_crypt(&io->work); 2238 return; 2239 } 2240 2241 INIT_WORK(&io->work, kcryptd_crypt); 2242 queue_work(cc->crypt_queue, &io->work); 2243 } 2244 2245 static void crypt_free_tfms_aead(struct crypt_config *cc) 2246 { 2247 if (!cc->cipher_tfm.tfms_aead) 2248 return; 2249 2250 if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2251 crypto_free_aead(cc->cipher_tfm.tfms_aead[0]); 2252 cc->cipher_tfm.tfms_aead[0] = NULL; 2253 } 2254 2255 kfree(cc->cipher_tfm.tfms_aead); 2256 cc->cipher_tfm.tfms_aead = NULL; 2257 } 2258 2259 static void crypt_free_tfms_skcipher(struct crypt_config *cc) 2260 { 2261 unsigned i; 2262 2263 if (!cc->cipher_tfm.tfms) 2264 return; 2265 2266 for (i = 0; i < cc->tfms_count; i++) 2267 if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) { 2268 crypto_free_skcipher(cc->cipher_tfm.tfms[i]); 2269 cc->cipher_tfm.tfms[i] = NULL; 2270 } 2271 2272 kfree(cc->cipher_tfm.tfms); 2273 cc->cipher_tfm.tfms = NULL; 2274 } 2275 2276 static void crypt_free_tfms(struct crypt_config *cc) 2277 { 2278 if (crypt_integrity_aead(cc)) 2279 crypt_free_tfms_aead(cc); 2280 else 2281 crypt_free_tfms_skcipher(cc); 2282 } 2283 2284 static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode) 2285 { 2286 unsigned i; 2287 int err; 2288 2289 cc->cipher_tfm.tfms = kcalloc(cc->tfms_count, 2290 sizeof(struct crypto_skcipher *), 2291 GFP_KERNEL); 2292 if (!cc->cipher_tfm.tfms) 2293 return -ENOMEM; 2294 2295 for (i = 0; i < cc->tfms_count; i++) { 2296 cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0, 2297 CRYPTO_ALG_ALLOCATES_MEMORY); 2298 if (IS_ERR(cc->cipher_tfm.tfms[i])) { 2299 err = PTR_ERR(cc->cipher_tfm.tfms[i]); 2300 crypt_free_tfms(cc); 2301 return err; 2302 } 2303 } 2304 2305 /* 2306 * dm-crypt performance can vary greatly depending on which crypto 2307 * algorithm implementation is used. Help people debug performance 2308 * problems by logging the ->cra_driver_name. 2309 */ 2310 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2311 crypto_skcipher_alg(any_tfm(cc))->base.cra_driver_name); 2312 return 0; 2313 } 2314 2315 static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode) 2316 { 2317 int err; 2318 2319 cc->cipher_tfm.tfms = kmalloc(sizeof(struct crypto_aead *), GFP_KERNEL); 2320 if (!cc->cipher_tfm.tfms) 2321 return -ENOMEM; 2322 2323 cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0, 2324 CRYPTO_ALG_ALLOCATES_MEMORY); 2325 if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2326 err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]); 2327 crypt_free_tfms(cc); 2328 return err; 2329 } 2330 2331 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2332 crypto_aead_alg(any_tfm_aead(cc))->base.cra_driver_name); 2333 return 0; 2334 } 2335 2336 static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode) 2337 { 2338 if (crypt_integrity_aead(cc)) 2339 return crypt_alloc_tfms_aead(cc, ciphermode); 2340 else 2341 return crypt_alloc_tfms_skcipher(cc, ciphermode); 2342 } 2343 2344 static unsigned crypt_subkey_size(struct crypt_config *cc) 2345 { 2346 return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count); 2347 } 2348 2349 static unsigned crypt_authenckey_size(struct crypt_config *cc) 2350 { 2351 return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param)); 2352 } 2353 2354 /* 2355 * If AEAD is composed like authenc(hmac(sha256),xts(aes)), 2356 * the key must be for some reason in special format. 2357 * This funcion converts cc->key to this special format. 2358 */ 2359 static void crypt_copy_authenckey(char *p, const void *key, 2360 unsigned enckeylen, unsigned authkeylen) 2361 { 2362 struct crypto_authenc_key_param *param; 2363 struct rtattr *rta; 2364 2365 rta = (struct rtattr *)p; 2366 param = RTA_DATA(rta); 2367 param->enckeylen = cpu_to_be32(enckeylen); 2368 rta->rta_len = RTA_LENGTH(sizeof(*param)); 2369 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; 2370 p += RTA_SPACE(sizeof(*param)); 2371 memcpy(p, key + enckeylen, authkeylen); 2372 p += authkeylen; 2373 memcpy(p, key, enckeylen); 2374 } 2375 2376 static int crypt_setkey(struct crypt_config *cc) 2377 { 2378 unsigned subkey_size; 2379 int err = 0, i, r; 2380 2381 /* Ignore extra keys (which are used for IV etc) */ 2382 subkey_size = crypt_subkey_size(cc); 2383 2384 if (crypt_integrity_hmac(cc)) { 2385 if (subkey_size < cc->key_mac_size) 2386 return -EINVAL; 2387 2388 crypt_copy_authenckey(cc->authenc_key, cc->key, 2389 subkey_size - cc->key_mac_size, 2390 cc->key_mac_size); 2391 } 2392 2393 for (i = 0; i < cc->tfms_count; i++) { 2394 if (crypt_integrity_hmac(cc)) 2395 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2396 cc->authenc_key, crypt_authenckey_size(cc)); 2397 else if (crypt_integrity_aead(cc)) 2398 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2399 cc->key + (i * subkey_size), 2400 subkey_size); 2401 else 2402 r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i], 2403 cc->key + (i * subkey_size), 2404 subkey_size); 2405 if (r) 2406 err = r; 2407 } 2408 2409 if (crypt_integrity_hmac(cc)) 2410 memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc)); 2411 2412 return err; 2413 } 2414 2415 #ifdef CONFIG_KEYS 2416 2417 static bool contains_whitespace(const char *str) 2418 { 2419 while (*str) 2420 if (isspace(*str++)) 2421 return true; 2422 return false; 2423 } 2424 2425 static int set_key_user(struct crypt_config *cc, struct key *key) 2426 { 2427 const struct user_key_payload *ukp; 2428 2429 ukp = user_key_payload_locked(key); 2430 if (!ukp) 2431 return -EKEYREVOKED; 2432 2433 if (cc->key_size != ukp->datalen) 2434 return -EINVAL; 2435 2436 memcpy(cc->key, ukp->data, cc->key_size); 2437 2438 return 0; 2439 } 2440 2441 static int set_key_encrypted(struct crypt_config *cc, struct key *key) 2442 { 2443 const struct encrypted_key_payload *ekp; 2444 2445 ekp = key->payload.data[0]; 2446 if (!ekp) 2447 return -EKEYREVOKED; 2448 2449 if (cc->key_size != ekp->decrypted_datalen) 2450 return -EINVAL; 2451 2452 memcpy(cc->key, ekp->decrypted_data, cc->key_size); 2453 2454 return 0; 2455 } 2456 2457 static int set_key_trusted(struct crypt_config *cc, struct key *key) 2458 { 2459 const struct trusted_key_payload *tkp; 2460 2461 tkp = key->payload.data[0]; 2462 if (!tkp) 2463 return -EKEYREVOKED; 2464 2465 if (cc->key_size != tkp->key_len) 2466 return -EINVAL; 2467 2468 memcpy(cc->key, tkp->key, cc->key_size); 2469 2470 return 0; 2471 } 2472 2473 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2474 { 2475 char *new_key_string, *key_desc; 2476 int ret; 2477 struct key_type *type; 2478 struct key *key; 2479 int (*set_key)(struct crypt_config *cc, struct key *key); 2480 2481 /* 2482 * Reject key_string with whitespace. dm core currently lacks code for 2483 * proper whitespace escaping in arguments on DM_TABLE_STATUS path. 2484 */ 2485 if (contains_whitespace(key_string)) { 2486 DMERR("whitespace chars not allowed in key string"); 2487 return -EINVAL; 2488 } 2489 2490 /* look for next ':' separating key_type from key_description */ 2491 key_desc = strpbrk(key_string, ":"); 2492 if (!key_desc || key_desc == key_string || !strlen(key_desc + 1)) 2493 return -EINVAL; 2494 2495 if (!strncmp(key_string, "logon:", key_desc - key_string + 1)) { 2496 type = &key_type_logon; 2497 set_key = set_key_user; 2498 } else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) { 2499 type = &key_type_user; 2500 set_key = set_key_user; 2501 } else if (IS_ENABLED(CONFIG_ENCRYPTED_KEYS) && 2502 !strncmp(key_string, "encrypted:", key_desc - key_string + 1)) { 2503 type = &key_type_encrypted; 2504 set_key = set_key_encrypted; 2505 } else if (IS_ENABLED(CONFIG_TRUSTED_KEYS) && 2506 !strncmp(key_string, "trusted:", key_desc - key_string + 1)) { 2507 type = &key_type_trusted; 2508 set_key = set_key_trusted; 2509 } else { 2510 return -EINVAL; 2511 } 2512 2513 new_key_string = kstrdup(key_string, GFP_KERNEL); 2514 if (!new_key_string) 2515 return -ENOMEM; 2516 2517 key = request_key(type, key_desc + 1, NULL); 2518 if (IS_ERR(key)) { 2519 kfree_sensitive(new_key_string); 2520 return PTR_ERR(key); 2521 } 2522 2523 down_read(&key->sem); 2524 2525 ret = set_key(cc, key); 2526 if (ret < 0) { 2527 up_read(&key->sem); 2528 key_put(key); 2529 kfree_sensitive(new_key_string); 2530 return ret; 2531 } 2532 2533 up_read(&key->sem); 2534 key_put(key); 2535 2536 /* clear the flag since following operations may invalidate previously valid key */ 2537 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2538 2539 ret = crypt_setkey(cc); 2540 2541 if (!ret) { 2542 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2543 kfree_sensitive(cc->key_string); 2544 cc->key_string = new_key_string; 2545 } else 2546 kfree_sensitive(new_key_string); 2547 2548 return ret; 2549 } 2550 2551 static int get_key_size(char **key_string) 2552 { 2553 char *colon, dummy; 2554 int ret; 2555 2556 if (*key_string[0] != ':') 2557 return strlen(*key_string) >> 1; 2558 2559 /* look for next ':' in key string */ 2560 colon = strpbrk(*key_string + 1, ":"); 2561 if (!colon) 2562 return -EINVAL; 2563 2564 if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':') 2565 return -EINVAL; 2566 2567 *key_string = colon; 2568 2569 /* remaining key string should be :<logon|user>:<key_desc> */ 2570 2571 return ret; 2572 } 2573 2574 #else 2575 2576 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2577 { 2578 return -EINVAL; 2579 } 2580 2581 static int get_key_size(char **key_string) 2582 { 2583 return (*key_string[0] == ':') ? -EINVAL : strlen(*key_string) >> 1; 2584 } 2585 2586 #endif /* CONFIG_KEYS */ 2587 2588 static int crypt_set_key(struct crypt_config *cc, char *key) 2589 { 2590 int r = -EINVAL; 2591 int key_string_len = strlen(key); 2592 2593 /* Hyphen (which gives a key_size of zero) means there is no key. */ 2594 if (!cc->key_size && strcmp(key, "-")) 2595 goto out; 2596 2597 /* ':' means the key is in kernel keyring, short-circuit normal key processing */ 2598 if (key[0] == ':') { 2599 r = crypt_set_keyring_key(cc, key + 1); 2600 goto out; 2601 } 2602 2603 /* clear the flag since following operations may invalidate previously valid key */ 2604 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2605 2606 /* wipe references to any kernel keyring key */ 2607 kfree_sensitive(cc->key_string); 2608 cc->key_string = NULL; 2609 2610 /* Decode key from its hex representation. */ 2611 if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0) 2612 goto out; 2613 2614 r = crypt_setkey(cc); 2615 if (!r) 2616 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2617 2618 out: 2619 /* Hex key string not needed after here, so wipe it. */ 2620 memset(key, '0', key_string_len); 2621 2622 return r; 2623 } 2624 2625 static int crypt_wipe_key(struct crypt_config *cc) 2626 { 2627 int r; 2628 2629 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2630 get_random_bytes(&cc->key, cc->key_size); 2631 2632 /* Wipe IV private keys */ 2633 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) { 2634 r = cc->iv_gen_ops->wipe(cc); 2635 if (r) 2636 return r; 2637 } 2638 2639 kfree_sensitive(cc->key_string); 2640 cc->key_string = NULL; 2641 r = crypt_setkey(cc); 2642 memset(&cc->key, 0, cc->key_size * sizeof(u8)); 2643 2644 return r; 2645 } 2646 2647 static void crypt_calculate_pages_per_client(void) 2648 { 2649 unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100; 2650 2651 if (!dm_crypt_clients_n) 2652 return; 2653 2654 pages /= dm_crypt_clients_n; 2655 if (pages < DM_CRYPT_MIN_PAGES_PER_CLIENT) 2656 pages = DM_CRYPT_MIN_PAGES_PER_CLIENT; 2657 dm_crypt_pages_per_client = pages; 2658 } 2659 2660 static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data) 2661 { 2662 struct crypt_config *cc = pool_data; 2663 struct page *page; 2664 2665 /* 2666 * Note, percpu_counter_read_positive() may over (and under) estimate 2667 * the current usage by at most (batch - 1) * num_online_cpus() pages, 2668 * but avoids potential spinlock contention of an exact result. 2669 */ 2670 if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) >= dm_crypt_pages_per_client) && 2671 likely(gfp_mask & __GFP_NORETRY)) 2672 return NULL; 2673 2674 page = alloc_page(gfp_mask); 2675 if (likely(page != NULL)) 2676 percpu_counter_add(&cc->n_allocated_pages, 1); 2677 2678 return page; 2679 } 2680 2681 static void crypt_page_free(void *page, void *pool_data) 2682 { 2683 struct crypt_config *cc = pool_data; 2684 2685 __free_page(page); 2686 percpu_counter_sub(&cc->n_allocated_pages, 1); 2687 } 2688 2689 static void crypt_dtr(struct dm_target *ti) 2690 { 2691 struct crypt_config *cc = ti->private; 2692 2693 ti->private = NULL; 2694 2695 if (!cc) 2696 return; 2697 2698 if (cc->write_thread) 2699 kthread_stop(cc->write_thread); 2700 2701 if (cc->io_queue) 2702 destroy_workqueue(cc->io_queue); 2703 if (cc->crypt_queue) 2704 destroy_workqueue(cc->crypt_queue); 2705 2706 crypt_free_tfms(cc); 2707 2708 bioset_exit(&cc->bs); 2709 2710 mempool_exit(&cc->page_pool); 2711 mempool_exit(&cc->req_pool); 2712 mempool_exit(&cc->tag_pool); 2713 2714 WARN_ON(percpu_counter_sum(&cc->n_allocated_pages) != 0); 2715 percpu_counter_destroy(&cc->n_allocated_pages); 2716 2717 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) 2718 cc->iv_gen_ops->dtr(cc); 2719 2720 if (cc->dev) 2721 dm_put_device(ti, cc->dev); 2722 2723 kfree_sensitive(cc->cipher_string); 2724 kfree_sensitive(cc->key_string); 2725 kfree_sensitive(cc->cipher_auth); 2726 kfree_sensitive(cc->authenc_key); 2727 2728 mutex_destroy(&cc->bio_alloc_lock); 2729 2730 /* Must zero key material before freeing */ 2731 kfree_sensitive(cc); 2732 2733 spin_lock(&dm_crypt_clients_lock); 2734 WARN_ON(!dm_crypt_clients_n); 2735 dm_crypt_clients_n--; 2736 crypt_calculate_pages_per_client(); 2737 spin_unlock(&dm_crypt_clients_lock); 2738 } 2739 2740 static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode) 2741 { 2742 struct crypt_config *cc = ti->private; 2743 2744 if (crypt_integrity_aead(cc)) 2745 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2746 else 2747 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2748 2749 if (cc->iv_size) 2750 /* at least a 64 bit sector number should fit in our buffer */ 2751 cc->iv_size = max(cc->iv_size, 2752 (unsigned int)(sizeof(u64) / sizeof(u8))); 2753 else if (ivmode) { 2754 DMWARN("Selected cipher does not support IVs"); 2755 ivmode = NULL; 2756 } 2757 2758 /* Choose ivmode, see comments at iv code. */ 2759 if (ivmode == NULL) 2760 cc->iv_gen_ops = NULL; 2761 else if (strcmp(ivmode, "plain") == 0) 2762 cc->iv_gen_ops = &crypt_iv_plain_ops; 2763 else if (strcmp(ivmode, "plain64") == 0) 2764 cc->iv_gen_ops = &crypt_iv_plain64_ops; 2765 else if (strcmp(ivmode, "plain64be") == 0) 2766 cc->iv_gen_ops = &crypt_iv_plain64be_ops; 2767 else if (strcmp(ivmode, "essiv") == 0) 2768 cc->iv_gen_ops = &crypt_iv_essiv_ops; 2769 else if (strcmp(ivmode, "benbi") == 0) 2770 cc->iv_gen_ops = &crypt_iv_benbi_ops; 2771 else if (strcmp(ivmode, "null") == 0) 2772 cc->iv_gen_ops = &crypt_iv_null_ops; 2773 else if (strcmp(ivmode, "eboiv") == 0) 2774 cc->iv_gen_ops = &crypt_iv_eboiv_ops; 2775 else if (strcmp(ivmode, "elephant") == 0) { 2776 cc->iv_gen_ops = &crypt_iv_elephant_ops; 2777 cc->key_parts = 2; 2778 cc->key_extra_size = cc->key_size / 2; 2779 if (cc->key_extra_size > ELEPHANT_MAX_KEY_SIZE) 2780 return -EINVAL; 2781 set_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags); 2782 } else if (strcmp(ivmode, "lmk") == 0) { 2783 cc->iv_gen_ops = &crypt_iv_lmk_ops; 2784 /* 2785 * Version 2 and 3 is recognised according 2786 * to length of provided multi-key string. 2787 * If present (version 3), last key is used as IV seed. 2788 * All keys (including IV seed) are always the same size. 2789 */ 2790 if (cc->key_size % cc->key_parts) { 2791 cc->key_parts++; 2792 cc->key_extra_size = cc->key_size / cc->key_parts; 2793 } 2794 } else if (strcmp(ivmode, "tcw") == 0) { 2795 cc->iv_gen_ops = &crypt_iv_tcw_ops; 2796 cc->key_parts += 2; /* IV + whitening */ 2797 cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE; 2798 } else if (strcmp(ivmode, "random") == 0) { 2799 cc->iv_gen_ops = &crypt_iv_random_ops; 2800 /* Need storage space in integrity fields. */ 2801 cc->integrity_iv_size = cc->iv_size; 2802 } else { 2803 ti->error = "Invalid IV mode"; 2804 return -EINVAL; 2805 } 2806 2807 return 0; 2808 } 2809 2810 /* 2811 * Workaround to parse HMAC algorithm from AEAD crypto API spec. 2812 * The HMAC is needed to calculate tag size (HMAC digest size). 2813 * This should be probably done by crypto-api calls (once available...) 2814 */ 2815 static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api) 2816 { 2817 char *start, *end, *mac_alg = NULL; 2818 struct crypto_ahash *mac; 2819 2820 if (!strstarts(cipher_api, "authenc(")) 2821 return 0; 2822 2823 start = strchr(cipher_api, '('); 2824 end = strchr(cipher_api, ','); 2825 if (!start || !end || ++start > end) 2826 return -EINVAL; 2827 2828 mac_alg = kzalloc(end - start + 1, GFP_KERNEL); 2829 if (!mac_alg) 2830 return -ENOMEM; 2831 strncpy(mac_alg, start, end - start); 2832 2833 mac = crypto_alloc_ahash(mac_alg, 0, CRYPTO_ALG_ALLOCATES_MEMORY); 2834 kfree(mac_alg); 2835 2836 if (IS_ERR(mac)) 2837 return PTR_ERR(mac); 2838 2839 cc->key_mac_size = crypto_ahash_digestsize(mac); 2840 crypto_free_ahash(mac); 2841 2842 cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL); 2843 if (!cc->authenc_key) 2844 return -ENOMEM; 2845 2846 return 0; 2847 } 2848 2849 static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key, 2850 char **ivmode, char **ivopts) 2851 { 2852 struct crypt_config *cc = ti->private; 2853 char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME]; 2854 int ret = -EINVAL; 2855 2856 cc->tfms_count = 1; 2857 2858 /* 2859 * New format (capi: prefix) 2860 * capi:cipher_api_spec-iv:ivopts 2861 */ 2862 tmp = &cipher_in[strlen("capi:")]; 2863 2864 /* Separate IV options if present, it can contain another '-' in hash name */ 2865 *ivopts = strrchr(tmp, ':'); 2866 if (*ivopts) { 2867 **ivopts = '\0'; 2868 (*ivopts)++; 2869 } 2870 /* Parse IV mode */ 2871 *ivmode = strrchr(tmp, '-'); 2872 if (*ivmode) { 2873 **ivmode = '\0'; 2874 (*ivmode)++; 2875 } 2876 /* The rest is crypto API spec */ 2877 cipher_api = tmp; 2878 2879 /* Alloc AEAD, can be used only in new format. */ 2880 if (crypt_integrity_aead(cc)) { 2881 ret = crypt_ctr_auth_cipher(cc, cipher_api); 2882 if (ret < 0) { 2883 ti->error = "Invalid AEAD cipher spec"; 2884 return -ENOMEM; 2885 } 2886 } 2887 2888 if (*ivmode && !strcmp(*ivmode, "lmk")) 2889 cc->tfms_count = 64; 2890 2891 if (*ivmode && !strcmp(*ivmode, "essiv")) { 2892 if (!*ivopts) { 2893 ti->error = "Digest algorithm missing for ESSIV mode"; 2894 return -EINVAL; 2895 } 2896 ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)", 2897 cipher_api, *ivopts); 2898 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 2899 ti->error = "Cannot allocate cipher string"; 2900 return -ENOMEM; 2901 } 2902 cipher_api = buf; 2903 } 2904 2905 cc->key_parts = cc->tfms_count; 2906 2907 /* Allocate cipher */ 2908 ret = crypt_alloc_tfms(cc, cipher_api); 2909 if (ret < 0) { 2910 ti->error = "Error allocating crypto tfm"; 2911 return ret; 2912 } 2913 2914 if (crypt_integrity_aead(cc)) 2915 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2916 else 2917 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2918 2919 return 0; 2920 } 2921 2922 static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key, 2923 char **ivmode, char **ivopts) 2924 { 2925 struct crypt_config *cc = ti->private; 2926 char *tmp, *cipher, *chainmode, *keycount; 2927 char *cipher_api = NULL; 2928 int ret = -EINVAL; 2929 char dummy; 2930 2931 if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) { 2932 ti->error = "Bad cipher specification"; 2933 return -EINVAL; 2934 } 2935 2936 /* 2937 * Legacy dm-crypt cipher specification 2938 * cipher[:keycount]-mode-iv:ivopts 2939 */ 2940 tmp = cipher_in; 2941 keycount = strsep(&tmp, "-"); 2942 cipher = strsep(&keycount, ":"); 2943 2944 if (!keycount) 2945 cc->tfms_count = 1; 2946 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 || 2947 !is_power_of_2(cc->tfms_count)) { 2948 ti->error = "Bad cipher key count specification"; 2949 return -EINVAL; 2950 } 2951 cc->key_parts = cc->tfms_count; 2952 2953 chainmode = strsep(&tmp, "-"); 2954 *ivmode = strsep(&tmp, ":"); 2955 *ivopts = tmp; 2956 2957 /* 2958 * For compatibility with the original dm-crypt mapping format, if 2959 * only the cipher name is supplied, use cbc-plain. 2960 */ 2961 if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) { 2962 chainmode = "cbc"; 2963 *ivmode = "plain"; 2964 } 2965 2966 if (strcmp(chainmode, "ecb") && !*ivmode) { 2967 ti->error = "IV mechanism required"; 2968 return -EINVAL; 2969 } 2970 2971 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL); 2972 if (!cipher_api) 2973 goto bad_mem; 2974 2975 if (*ivmode && !strcmp(*ivmode, "essiv")) { 2976 if (!*ivopts) { 2977 ti->error = "Digest algorithm missing for ESSIV mode"; 2978 kfree(cipher_api); 2979 return -EINVAL; 2980 } 2981 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 2982 "essiv(%s(%s),%s)", chainmode, cipher, *ivopts); 2983 } else { 2984 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 2985 "%s(%s)", chainmode, cipher); 2986 } 2987 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 2988 kfree(cipher_api); 2989 goto bad_mem; 2990 } 2991 2992 /* Allocate cipher */ 2993 ret = crypt_alloc_tfms(cc, cipher_api); 2994 if (ret < 0) { 2995 ti->error = "Error allocating crypto tfm"; 2996 kfree(cipher_api); 2997 return ret; 2998 } 2999 kfree(cipher_api); 3000 3001 return 0; 3002 bad_mem: 3003 ti->error = "Cannot allocate cipher strings"; 3004 return -ENOMEM; 3005 } 3006 3007 static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key) 3008 { 3009 struct crypt_config *cc = ti->private; 3010 char *ivmode = NULL, *ivopts = NULL; 3011 int ret; 3012 3013 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL); 3014 if (!cc->cipher_string) { 3015 ti->error = "Cannot allocate cipher strings"; 3016 return -ENOMEM; 3017 } 3018 3019 if (strstarts(cipher_in, "capi:")) 3020 ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts); 3021 else 3022 ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts); 3023 if (ret) 3024 return ret; 3025 3026 /* Initialize IV */ 3027 ret = crypt_ctr_ivmode(ti, ivmode); 3028 if (ret < 0) 3029 return ret; 3030 3031 /* Initialize and set key */ 3032 ret = crypt_set_key(cc, key); 3033 if (ret < 0) { 3034 ti->error = "Error decoding and setting key"; 3035 return ret; 3036 } 3037 3038 /* Allocate IV */ 3039 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) { 3040 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts); 3041 if (ret < 0) { 3042 ti->error = "Error creating IV"; 3043 return ret; 3044 } 3045 } 3046 3047 /* Initialize IV (set keys for ESSIV etc) */ 3048 if (cc->iv_gen_ops && cc->iv_gen_ops->init) { 3049 ret = cc->iv_gen_ops->init(cc); 3050 if (ret < 0) { 3051 ti->error = "Error initialising IV"; 3052 return ret; 3053 } 3054 } 3055 3056 /* wipe the kernel key payload copy */ 3057 if (cc->key_string) 3058 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3059 3060 return ret; 3061 } 3062 3063 static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv) 3064 { 3065 struct crypt_config *cc = ti->private; 3066 struct dm_arg_set as; 3067 static const struct dm_arg _args[] = { 3068 {0, 8, "Invalid number of feature args"}, 3069 }; 3070 unsigned int opt_params, val; 3071 const char *opt_string, *sval; 3072 char dummy; 3073 int ret; 3074 3075 /* Optional parameters */ 3076 as.argc = argc; 3077 as.argv = argv; 3078 3079 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error); 3080 if (ret) 3081 return ret; 3082 3083 while (opt_params--) { 3084 opt_string = dm_shift_arg(&as); 3085 if (!opt_string) { 3086 ti->error = "Not enough feature arguments"; 3087 return -EINVAL; 3088 } 3089 3090 if (!strcasecmp(opt_string, "allow_discards")) 3091 ti->num_discard_bios = 1; 3092 3093 else if (!strcasecmp(opt_string, "same_cpu_crypt")) 3094 set_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3095 3096 else if (!strcasecmp(opt_string, "submit_from_crypt_cpus")) 3097 set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3098 else if (!strcasecmp(opt_string, "no_read_workqueue")) 3099 set_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3100 else if (!strcasecmp(opt_string, "no_write_workqueue")) 3101 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3102 else if (sscanf(opt_string, "integrity:%u:", &val) == 1) { 3103 if (val == 0 || val > MAX_TAG_SIZE) { 3104 ti->error = "Invalid integrity arguments"; 3105 return -EINVAL; 3106 } 3107 cc->on_disk_tag_size = val; 3108 sval = strchr(opt_string + strlen("integrity:"), ':') + 1; 3109 if (!strcasecmp(sval, "aead")) { 3110 set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 3111 } else if (strcasecmp(sval, "none")) { 3112 ti->error = "Unknown integrity profile"; 3113 return -EINVAL; 3114 } 3115 3116 cc->cipher_auth = kstrdup(sval, GFP_KERNEL); 3117 if (!cc->cipher_auth) 3118 return -ENOMEM; 3119 } else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) { 3120 if (cc->sector_size < (1 << SECTOR_SHIFT) || 3121 cc->sector_size > 4096 || 3122 (cc->sector_size & (cc->sector_size - 1))) { 3123 ti->error = "Invalid feature value for sector_size"; 3124 return -EINVAL; 3125 } 3126 if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) { 3127 ti->error = "Device size is not multiple of sector_size feature"; 3128 return -EINVAL; 3129 } 3130 cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT; 3131 } else if (!strcasecmp(opt_string, "iv_large_sectors")) 3132 set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3133 else { 3134 ti->error = "Invalid feature arguments"; 3135 return -EINVAL; 3136 } 3137 } 3138 3139 return 0; 3140 } 3141 3142 #ifdef CONFIG_BLK_DEV_ZONED 3143 static int crypt_report_zones(struct dm_target *ti, 3144 struct dm_report_zones_args *args, unsigned int nr_zones) 3145 { 3146 struct crypt_config *cc = ti->private; 3147 3148 return dm_report_zones(cc->dev->bdev, cc->start, 3149 cc->start + dm_target_offset(ti, args->next_sector), 3150 args, nr_zones); 3151 } 3152 #else 3153 #define crypt_report_zones NULL 3154 #endif 3155 3156 /* 3157 * Construct an encryption mapping: 3158 * <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start> 3159 */ 3160 static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) 3161 { 3162 struct crypt_config *cc; 3163 const char *devname = dm_table_device_name(ti->table); 3164 int key_size; 3165 unsigned int align_mask; 3166 unsigned long long tmpll; 3167 int ret; 3168 size_t iv_size_padding, additional_req_size; 3169 char dummy; 3170 3171 if (argc < 5) { 3172 ti->error = "Not enough arguments"; 3173 return -EINVAL; 3174 } 3175 3176 key_size = get_key_size(&argv[1]); 3177 if (key_size < 0) { 3178 ti->error = "Cannot parse key size"; 3179 return -EINVAL; 3180 } 3181 3182 cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL); 3183 if (!cc) { 3184 ti->error = "Cannot allocate encryption context"; 3185 return -ENOMEM; 3186 } 3187 cc->key_size = key_size; 3188 cc->sector_size = (1 << SECTOR_SHIFT); 3189 cc->sector_shift = 0; 3190 3191 ti->private = cc; 3192 3193 spin_lock(&dm_crypt_clients_lock); 3194 dm_crypt_clients_n++; 3195 crypt_calculate_pages_per_client(); 3196 spin_unlock(&dm_crypt_clients_lock); 3197 3198 ret = percpu_counter_init(&cc->n_allocated_pages, 0, GFP_KERNEL); 3199 if (ret < 0) 3200 goto bad; 3201 3202 /* Optional parameters need to be read before cipher constructor */ 3203 if (argc > 5) { 3204 ret = crypt_ctr_optional(ti, argc - 5, &argv[5]); 3205 if (ret) 3206 goto bad; 3207 } 3208 3209 ret = crypt_ctr_cipher(ti, argv[0], argv[1]); 3210 if (ret < 0) 3211 goto bad; 3212 3213 if (crypt_integrity_aead(cc)) { 3214 cc->dmreq_start = sizeof(struct aead_request); 3215 cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc)); 3216 align_mask = crypto_aead_alignmask(any_tfm_aead(cc)); 3217 } else { 3218 cc->dmreq_start = sizeof(struct skcipher_request); 3219 cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc)); 3220 align_mask = crypto_skcipher_alignmask(any_tfm(cc)); 3221 } 3222 cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request)); 3223 3224 if (align_mask < CRYPTO_MINALIGN) { 3225 /* Allocate the padding exactly */ 3226 iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request)) 3227 & align_mask; 3228 } else { 3229 /* 3230 * If the cipher requires greater alignment than kmalloc 3231 * alignment, we don't know the exact position of the 3232 * initialization vector. We must assume worst case. 3233 */ 3234 iv_size_padding = align_mask; 3235 } 3236 3237 /* ...| IV + padding | original IV | original sec. number | bio tag offset | */ 3238 additional_req_size = sizeof(struct dm_crypt_request) + 3239 iv_size_padding + cc->iv_size + 3240 cc->iv_size + 3241 sizeof(uint64_t) + 3242 sizeof(unsigned int); 3243 3244 ret = mempool_init_kmalloc_pool(&cc->req_pool, MIN_IOS, cc->dmreq_start + additional_req_size); 3245 if (ret) { 3246 ti->error = "Cannot allocate crypt request mempool"; 3247 goto bad; 3248 } 3249 3250 cc->per_bio_data_size = ti->per_io_data_size = 3251 ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size, 3252 ARCH_KMALLOC_MINALIGN); 3253 3254 ret = mempool_init(&cc->page_pool, BIO_MAX_VECS, crypt_page_alloc, crypt_page_free, cc); 3255 if (ret) { 3256 ti->error = "Cannot allocate page mempool"; 3257 goto bad; 3258 } 3259 3260 ret = bioset_init(&cc->bs, MIN_IOS, 0, BIOSET_NEED_BVECS); 3261 if (ret) { 3262 ti->error = "Cannot allocate crypt bioset"; 3263 goto bad; 3264 } 3265 3266 mutex_init(&cc->bio_alloc_lock); 3267 3268 ret = -EINVAL; 3269 if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) || 3270 (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) { 3271 ti->error = "Invalid iv_offset sector"; 3272 goto bad; 3273 } 3274 cc->iv_offset = tmpll; 3275 3276 ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev); 3277 if (ret) { 3278 ti->error = "Device lookup failed"; 3279 goto bad; 3280 } 3281 3282 ret = -EINVAL; 3283 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) { 3284 ti->error = "Invalid device sector"; 3285 goto bad; 3286 } 3287 cc->start = tmpll; 3288 3289 if (bdev_is_zoned(cc->dev->bdev)) { 3290 /* 3291 * For zoned block devices, we need to preserve the issuer write 3292 * ordering. To do so, disable write workqueues and force inline 3293 * encryption completion. 3294 */ 3295 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3296 set_bit(DM_CRYPT_WRITE_INLINE, &cc->flags); 3297 3298 /* 3299 * All zone append writes to a zone of a zoned block device will 3300 * have the same BIO sector, the start of the zone. When the 3301 * cypher IV mode uses sector values, all data targeting a 3302 * zone will be encrypted using the first sector numbers of the 3303 * zone. This will not result in write errors but will 3304 * cause most reads to fail as reads will use the sector values 3305 * for the actual data locations, resulting in IV mismatch. 3306 * To avoid this problem, ask DM core to emulate zone append 3307 * operations with regular writes. 3308 */ 3309 DMDEBUG("Zone append operations will be emulated"); 3310 ti->emulate_zone_append = true; 3311 } 3312 3313 if (crypt_integrity_aead(cc) || cc->integrity_iv_size) { 3314 ret = crypt_integrity_ctr(cc, ti); 3315 if (ret) 3316 goto bad; 3317 3318 cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->on_disk_tag_size; 3319 if (!cc->tag_pool_max_sectors) 3320 cc->tag_pool_max_sectors = 1; 3321 3322 ret = mempool_init_kmalloc_pool(&cc->tag_pool, MIN_IOS, 3323 cc->tag_pool_max_sectors * cc->on_disk_tag_size); 3324 if (ret) { 3325 ti->error = "Cannot allocate integrity tags mempool"; 3326 goto bad; 3327 } 3328 3329 cc->tag_pool_max_sectors <<= cc->sector_shift; 3330 } 3331 3332 ret = -ENOMEM; 3333 cc->io_queue = alloc_workqueue("kcryptd_io/%s", WQ_MEM_RECLAIM, 1, devname); 3334 if (!cc->io_queue) { 3335 ti->error = "Couldn't create kcryptd io queue"; 3336 goto bad; 3337 } 3338 3339 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3340 cc->crypt_queue = alloc_workqueue("kcryptd/%s", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 3341 1, devname); 3342 else 3343 cc->crypt_queue = alloc_workqueue("kcryptd/%s", 3344 WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND, 3345 num_online_cpus(), devname); 3346 if (!cc->crypt_queue) { 3347 ti->error = "Couldn't create kcryptd queue"; 3348 goto bad; 3349 } 3350 3351 spin_lock_init(&cc->write_thread_lock); 3352 cc->write_tree = RB_ROOT; 3353 3354 cc->write_thread = kthread_create(dmcrypt_write, cc, "dmcrypt_write/%s", devname); 3355 if (IS_ERR(cc->write_thread)) { 3356 ret = PTR_ERR(cc->write_thread); 3357 cc->write_thread = NULL; 3358 ti->error = "Couldn't spawn write thread"; 3359 goto bad; 3360 } 3361 wake_up_process(cc->write_thread); 3362 3363 ti->num_flush_bios = 1; 3364 ti->limit_swap_bios = true; 3365 3366 return 0; 3367 3368 bad: 3369 crypt_dtr(ti); 3370 return ret; 3371 } 3372 3373 static int crypt_map(struct dm_target *ti, struct bio *bio) 3374 { 3375 struct dm_crypt_io *io; 3376 struct crypt_config *cc = ti->private; 3377 3378 /* 3379 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues. 3380 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight 3381 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters 3382 */ 3383 if (unlikely(bio->bi_opf & REQ_PREFLUSH || 3384 bio_op(bio) == REQ_OP_DISCARD)) { 3385 bio_set_dev(bio, cc->dev->bdev); 3386 if (bio_sectors(bio)) 3387 bio->bi_iter.bi_sector = cc->start + 3388 dm_target_offset(ti, bio->bi_iter.bi_sector); 3389 return DM_MAPIO_REMAPPED; 3390 } 3391 3392 /* 3393 * Check if bio is too large, split as needed. 3394 */ 3395 if (unlikely(bio->bi_iter.bi_size > (BIO_MAX_VECS << PAGE_SHIFT)) && 3396 (bio_data_dir(bio) == WRITE || cc->on_disk_tag_size)) 3397 dm_accept_partial_bio(bio, ((BIO_MAX_VECS << PAGE_SHIFT) >> SECTOR_SHIFT)); 3398 3399 /* 3400 * Ensure that bio is a multiple of internal sector encryption size 3401 * and is aligned to this size as defined in IO hints. 3402 */ 3403 if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0)) 3404 return DM_MAPIO_KILL; 3405 3406 if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1))) 3407 return DM_MAPIO_KILL; 3408 3409 io = dm_per_bio_data(bio, cc->per_bio_data_size); 3410 crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector)); 3411 3412 if (cc->on_disk_tag_size) { 3413 unsigned tag_len = cc->on_disk_tag_size * (bio_sectors(bio) >> cc->sector_shift); 3414 3415 if (unlikely(tag_len > KMALLOC_MAX_SIZE) || 3416 unlikely(!(io->integrity_metadata = kmalloc(tag_len, 3417 GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN)))) { 3418 if (bio_sectors(bio) > cc->tag_pool_max_sectors) 3419 dm_accept_partial_bio(bio, cc->tag_pool_max_sectors); 3420 io->integrity_metadata = mempool_alloc(&cc->tag_pool, GFP_NOIO); 3421 io->integrity_metadata_from_pool = true; 3422 } 3423 } 3424 3425 if (crypt_integrity_aead(cc)) 3426 io->ctx.r.req_aead = (struct aead_request *)(io + 1); 3427 else 3428 io->ctx.r.req = (struct skcipher_request *)(io + 1); 3429 3430 if (bio_data_dir(io->base_bio) == READ) { 3431 if (kcryptd_io_read(io, GFP_NOWAIT)) 3432 kcryptd_queue_read(io); 3433 } else 3434 kcryptd_queue_crypt(io); 3435 3436 return DM_MAPIO_SUBMITTED; 3437 } 3438 3439 static void crypt_status(struct dm_target *ti, status_type_t type, 3440 unsigned status_flags, char *result, unsigned maxlen) 3441 { 3442 struct crypt_config *cc = ti->private; 3443 unsigned i, sz = 0; 3444 int num_feature_args = 0; 3445 3446 switch (type) { 3447 case STATUSTYPE_INFO: 3448 result[0] = '\0'; 3449 break; 3450 3451 case STATUSTYPE_TABLE: 3452 DMEMIT("%s ", cc->cipher_string); 3453 3454 if (cc->key_size > 0) { 3455 if (cc->key_string) 3456 DMEMIT(":%u:%s", cc->key_size, cc->key_string); 3457 else 3458 for (i = 0; i < cc->key_size; i++) 3459 DMEMIT("%02x", cc->key[i]); 3460 } else 3461 DMEMIT("-"); 3462 3463 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, 3464 cc->dev->name, (unsigned long long)cc->start); 3465 3466 num_feature_args += !!ti->num_discard_bios; 3467 num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3468 num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3469 num_feature_args += test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3470 num_feature_args += test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3471 num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT); 3472 num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3473 if (cc->on_disk_tag_size) 3474 num_feature_args++; 3475 if (num_feature_args) { 3476 DMEMIT(" %d", num_feature_args); 3477 if (ti->num_discard_bios) 3478 DMEMIT(" allow_discards"); 3479 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3480 DMEMIT(" same_cpu_crypt"); 3481 if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) 3482 DMEMIT(" submit_from_crypt_cpus"); 3483 if (test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) 3484 DMEMIT(" no_read_workqueue"); 3485 if (test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) 3486 DMEMIT(" no_write_workqueue"); 3487 if (cc->on_disk_tag_size) 3488 DMEMIT(" integrity:%u:%s", cc->on_disk_tag_size, cc->cipher_auth); 3489 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3490 DMEMIT(" sector_size:%d", cc->sector_size); 3491 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 3492 DMEMIT(" iv_large_sectors"); 3493 } 3494 break; 3495 3496 case STATUSTYPE_IMA: 3497 DMEMIT_TARGET_NAME_VERSION(ti->type); 3498 DMEMIT(",allow_discards=%c", ti->num_discard_bios ? 'y' : 'n'); 3499 DMEMIT(",same_cpu_crypt=%c", test_bit(DM_CRYPT_SAME_CPU, &cc->flags) ? 'y' : 'n'); 3500 DMEMIT(",submit_from_crypt_cpus=%c", test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags) ? 3501 'y' : 'n'); 3502 DMEMIT(",no_read_workqueue=%c", test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags) ? 3503 'y' : 'n'); 3504 DMEMIT(",no_write_workqueue=%c", test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags) ? 3505 'y' : 'n'); 3506 DMEMIT(",iv_large_sectors=%c", test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags) ? 3507 'y' : 'n'); 3508 3509 if (cc->on_disk_tag_size) 3510 DMEMIT(",integrity_tag_size=%u,cipher_auth=%s", 3511 cc->on_disk_tag_size, cc->cipher_auth); 3512 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3513 DMEMIT(",sector_size=%d", cc->sector_size); 3514 if (cc->cipher_string) 3515 DMEMIT(",cipher_string=%s", cc->cipher_string); 3516 3517 DMEMIT(",key_size=%u", cc->key_size); 3518 DMEMIT(",key_parts=%u", cc->key_parts); 3519 DMEMIT(",key_extra_size=%u", cc->key_extra_size); 3520 DMEMIT(",key_mac_size=%u", cc->key_mac_size); 3521 DMEMIT(";"); 3522 break; 3523 } 3524 } 3525 3526 static void crypt_postsuspend(struct dm_target *ti) 3527 { 3528 struct crypt_config *cc = ti->private; 3529 3530 set_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3531 } 3532 3533 static int crypt_preresume(struct dm_target *ti) 3534 { 3535 struct crypt_config *cc = ti->private; 3536 3537 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { 3538 DMERR("aborting resume - crypt key is not set."); 3539 return -EAGAIN; 3540 } 3541 3542 return 0; 3543 } 3544 3545 static void crypt_resume(struct dm_target *ti) 3546 { 3547 struct crypt_config *cc = ti->private; 3548 3549 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3550 } 3551 3552 /* Message interface 3553 * key set <key> 3554 * key wipe 3555 */ 3556 static int crypt_message(struct dm_target *ti, unsigned argc, char **argv, 3557 char *result, unsigned maxlen) 3558 { 3559 struct crypt_config *cc = ti->private; 3560 int key_size, ret = -EINVAL; 3561 3562 if (argc < 2) 3563 goto error; 3564 3565 if (!strcasecmp(argv[0], "key")) { 3566 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { 3567 DMWARN("not suspended during key manipulation."); 3568 return -EINVAL; 3569 } 3570 if (argc == 3 && !strcasecmp(argv[1], "set")) { 3571 /* The key size may not be changed. */ 3572 key_size = get_key_size(&argv[2]); 3573 if (key_size < 0 || cc->key_size != key_size) { 3574 memset(argv[2], '0', strlen(argv[2])); 3575 return -EINVAL; 3576 } 3577 3578 ret = crypt_set_key(cc, argv[2]); 3579 if (ret) 3580 return ret; 3581 if (cc->iv_gen_ops && cc->iv_gen_ops->init) 3582 ret = cc->iv_gen_ops->init(cc); 3583 /* wipe the kernel key payload copy */ 3584 if (cc->key_string) 3585 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3586 return ret; 3587 } 3588 if (argc == 2 && !strcasecmp(argv[1], "wipe")) 3589 return crypt_wipe_key(cc); 3590 } 3591 3592 error: 3593 DMWARN("unrecognised message received."); 3594 return -EINVAL; 3595 } 3596 3597 static int crypt_iterate_devices(struct dm_target *ti, 3598 iterate_devices_callout_fn fn, void *data) 3599 { 3600 struct crypt_config *cc = ti->private; 3601 3602 return fn(ti, cc->dev, cc->start, ti->len, data); 3603 } 3604 3605 static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits) 3606 { 3607 struct crypt_config *cc = ti->private; 3608 3609 /* 3610 * Unfortunate constraint that is required to avoid the potential 3611 * for exceeding underlying device's max_segments limits -- due to 3612 * crypt_alloc_buffer() possibly allocating pages for the encryption 3613 * bio that are not as physically contiguous as the original bio. 3614 */ 3615 limits->max_segment_size = PAGE_SIZE; 3616 3617 limits->logical_block_size = 3618 max_t(unsigned, limits->logical_block_size, cc->sector_size); 3619 limits->physical_block_size = 3620 max_t(unsigned, limits->physical_block_size, cc->sector_size); 3621 limits->io_min = max_t(unsigned, limits->io_min, cc->sector_size); 3622 } 3623 3624 static struct target_type crypt_target = { 3625 .name = "crypt", 3626 .version = {1, 23, 0}, 3627 .module = THIS_MODULE, 3628 .ctr = crypt_ctr, 3629 .dtr = crypt_dtr, 3630 .features = DM_TARGET_ZONED_HM, 3631 .report_zones = crypt_report_zones, 3632 .map = crypt_map, 3633 .status = crypt_status, 3634 .postsuspend = crypt_postsuspend, 3635 .preresume = crypt_preresume, 3636 .resume = crypt_resume, 3637 .message = crypt_message, 3638 .iterate_devices = crypt_iterate_devices, 3639 .io_hints = crypt_io_hints, 3640 }; 3641 3642 static int __init dm_crypt_init(void) 3643 { 3644 int r; 3645 3646 r = dm_register_target(&crypt_target); 3647 if (r < 0) 3648 DMERR("register failed %d", r); 3649 3650 return r; 3651 } 3652 3653 static void __exit dm_crypt_exit(void) 3654 { 3655 dm_unregister_target(&crypt_target); 3656 } 3657 3658 module_init(dm_crypt_init); 3659 module_exit(dm_crypt_exit); 3660 3661 MODULE_AUTHOR("Jana Saout <jana@saout.de>"); 3662 MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); 3663 MODULE_LICENSE("GPL"); 3664