1 /* 2 * Copyright (C) 2003 Jana Saout <jana@saout.de> 3 * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org> 4 * Copyright (C) 2006-2020 Red Hat, Inc. All rights reserved. 5 * Copyright (C) 2013-2020 Milan Broz <gmazyland@gmail.com> 6 * 7 * This file is released under the GPL. 8 */ 9 10 #include <linux/completion.h> 11 #include <linux/err.h> 12 #include <linux/module.h> 13 #include <linux/init.h> 14 #include <linux/kernel.h> 15 #include <linux/key.h> 16 #include <linux/bio.h> 17 #include <linux/blkdev.h> 18 #include <linux/blk-integrity.h> 19 #include <linux/mempool.h> 20 #include <linux/slab.h> 21 #include <linux/crypto.h> 22 #include <linux/workqueue.h> 23 #include <linux/kthread.h> 24 #include <linux/backing-dev.h> 25 #include <linux/atomic.h> 26 #include <linux/scatterlist.h> 27 #include <linux/rbtree.h> 28 #include <linux/ctype.h> 29 #include <asm/page.h> 30 #include <asm/unaligned.h> 31 #include <crypto/hash.h> 32 #include <crypto/md5.h> 33 #include <crypto/algapi.h> 34 #include <crypto/skcipher.h> 35 #include <crypto/aead.h> 36 #include <crypto/authenc.h> 37 #include <linux/rtnetlink.h> /* for struct rtattr and RTA macros only */ 38 #include <linux/key-type.h> 39 #include <keys/user-type.h> 40 #include <keys/encrypted-type.h> 41 #include <keys/trusted-type.h> 42 43 #include <linux/device-mapper.h> 44 45 #include "dm-audit.h" 46 47 #define DM_MSG_PREFIX "crypt" 48 49 /* 50 * context holding the current state of a multi-part conversion 51 */ 52 struct convert_context { 53 struct completion restart; 54 struct bio *bio_in; 55 struct bio *bio_out; 56 struct bvec_iter iter_in; 57 struct bvec_iter iter_out; 58 u64 cc_sector; 59 atomic_t cc_pending; 60 union { 61 struct skcipher_request *req; 62 struct aead_request *req_aead; 63 } r; 64 65 }; 66 67 /* 68 * per bio private data 69 */ 70 struct dm_crypt_io { 71 struct crypt_config *cc; 72 struct bio *base_bio; 73 u8 *integrity_metadata; 74 bool integrity_metadata_from_pool; 75 struct work_struct work; 76 struct tasklet_struct tasklet; 77 78 struct convert_context ctx; 79 80 atomic_t io_pending; 81 blk_status_t error; 82 sector_t sector; 83 84 struct rb_node rb_node; 85 } CRYPTO_MINALIGN_ATTR; 86 87 struct dm_crypt_request { 88 struct convert_context *ctx; 89 struct scatterlist sg_in[4]; 90 struct scatterlist sg_out[4]; 91 u64 iv_sector; 92 }; 93 94 struct crypt_config; 95 96 struct crypt_iv_operations { 97 int (*ctr)(struct crypt_config *cc, struct dm_target *ti, 98 const char *opts); 99 void (*dtr)(struct crypt_config *cc); 100 int (*init)(struct crypt_config *cc); 101 int (*wipe)(struct crypt_config *cc); 102 int (*generator)(struct crypt_config *cc, u8 *iv, 103 struct dm_crypt_request *dmreq); 104 int (*post)(struct crypt_config *cc, u8 *iv, 105 struct dm_crypt_request *dmreq); 106 }; 107 108 struct iv_benbi_private { 109 int shift; 110 }; 111 112 #define LMK_SEED_SIZE 64 /* hash + 0 */ 113 struct iv_lmk_private { 114 struct crypto_shash *hash_tfm; 115 u8 *seed; 116 }; 117 118 #define TCW_WHITENING_SIZE 16 119 struct iv_tcw_private { 120 struct crypto_shash *crc32_tfm; 121 u8 *iv_seed; 122 u8 *whitening; 123 }; 124 125 #define ELEPHANT_MAX_KEY_SIZE 32 126 struct iv_elephant_private { 127 struct crypto_skcipher *tfm; 128 }; 129 130 /* 131 * Crypt: maps a linear range of a block device 132 * and encrypts / decrypts at the same time. 133 */ 134 enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID, 135 DM_CRYPT_SAME_CPU, DM_CRYPT_NO_OFFLOAD, 136 DM_CRYPT_NO_READ_WORKQUEUE, DM_CRYPT_NO_WRITE_WORKQUEUE, 137 DM_CRYPT_WRITE_INLINE }; 138 139 enum cipher_flags { 140 CRYPT_MODE_INTEGRITY_AEAD, /* Use authenticated mode for cipher */ 141 CRYPT_IV_LARGE_SECTORS, /* Calculate IV from sector_size, not 512B sectors */ 142 CRYPT_ENCRYPT_PREPROCESS, /* Must preprocess data for encryption (elephant) */ 143 }; 144 145 /* 146 * The fields in here must be read only after initialization. 147 */ 148 struct crypt_config { 149 struct dm_dev *dev; 150 sector_t start; 151 152 struct percpu_counter n_allocated_pages; 153 154 struct workqueue_struct *io_queue; 155 struct workqueue_struct *crypt_queue; 156 157 spinlock_t write_thread_lock; 158 struct task_struct *write_thread; 159 struct rb_root write_tree; 160 161 char *cipher_string; 162 char *cipher_auth; 163 char *key_string; 164 165 const struct crypt_iv_operations *iv_gen_ops; 166 union { 167 struct iv_benbi_private benbi; 168 struct iv_lmk_private lmk; 169 struct iv_tcw_private tcw; 170 struct iv_elephant_private elephant; 171 } iv_gen_private; 172 u64 iv_offset; 173 unsigned int iv_size; 174 unsigned short int sector_size; 175 unsigned char sector_shift; 176 177 union { 178 struct crypto_skcipher **tfms; 179 struct crypto_aead **tfms_aead; 180 } cipher_tfm; 181 unsigned tfms_count; 182 unsigned long cipher_flags; 183 184 /* 185 * Layout of each crypto request: 186 * 187 * struct skcipher_request 188 * context 189 * padding 190 * struct dm_crypt_request 191 * padding 192 * IV 193 * 194 * The padding is added so that dm_crypt_request and the IV are 195 * correctly aligned. 196 */ 197 unsigned int dmreq_start; 198 199 unsigned int per_bio_data_size; 200 201 unsigned long flags; 202 unsigned int key_size; 203 unsigned int key_parts; /* independent parts in key buffer */ 204 unsigned int key_extra_size; /* additional keys length */ 205 unsigned int key_mac_size; /* MAC key size for authenc(...) */ 206 207 unsigned int integrity_tag_size; 208 unsigned int integrity_iv_size; 209 unsigned int on_disk_tag_size; 210 211 /* 212 * pool for per bio private data, crypto requests, 213 * encryption requeusts/buffer pages and integrity tags 214 */ 215 unsigned tag_pool_max_sectors; 216 mempool_t tag_pool; 217 mempool_t req_pool; 218 mempool_t page_pool; 219 220 struct bio_set bs; 221 struct mutex bio_alloc_lock; 222 223 u8 *authenc_key; /* space for keys in authenc() format (if used) */ 224 u8 key[]; 225 }; 226 227 #define MIN_IOS 64 228 #define MAX_TAG_SIZE 480 229 #define POOL_ENTRY_SIZE 512 230 231 static DEFINE_SPINLOCK(dm_crypt_clients_lock); 232 static unsigned dm_crypt_clients_n = 0; 233 static volatile unsigned long dm_crypt_pages_per_client; 234 #define DM_CRYPT_MEMORY_PERCENT 2 235 #define DM_CRYPT_MIN_PAGES_PER_CLIENT (BIO_MAX_VECS * 16) 236 237 static void clone_init(struct dm_crypt_io *, struct bio *); 238 static void kcryptd_queue_crypt(struct dm_crypt_io *io); 239 static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 240 struct scatterlist *sg); 241 242 static bool crypt_integrity_aead(struct crypt_config *cc); 243 244 /* 245 * Use this to access cipher attributes that are independent of the key. 246 */ 247 static struct crypto_skcipher *any_tfm(struct crypt_config *cc) 248 { 249 return cc->cipher_tfm.tfms[0]; 250 } 251 252 static struct crypto_aead *any_tfm_aead(struct crypt_config *cc) 253 { 254 return cc->cipher_tfm.tfms_aead[0]; 255 } 256 257 /* 258 * Different IV generation algorithms: 259 * 260 * plain: the initial vector is the 32-bit little-endian version of the sector 261 * number, padded with zeros if necessary. 262 * 263 * plain64: the initial vector is the 64-bit little-endian version of the sector 264 * number, padded with zeros if necessary. 265 * 266 * plain64be: the initial vector is the 64-bit big-endian version of the sector 267 * number, padded with zeros if necessary. 268 * 269 * essiv: "encrypted sector|salt initial vector", the sector number is 270 * encrypted with the bulk cipher using a salt as key. The salt 271 * should be derived from the bulk cipher's key via hashing. 272 * 273 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 274 * (needed for LRW-32-AES and possible other narrow block modes) 275 * 276 * null: the initial vector is always zero. Provides compatibility with 277 * obsolete loop_fish2 devices. Do not use for new devices. 278 * 279 * lmk: Compatible implementation of the block chaining mode used 280 * by the Loop-AES block device encryption system 281 * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/ 282 * It operates on full 512 byte sectors and uses CBC 283 * with an IV derived from the sector number, the data and 284 * optionally extra IV seed. 285 * This means that after decryption the first block 286 * of sector must be tweaked according to decrypted data. 287 * Loop-AES can use three encryption schemes: 288 * version 1: is plain aes-cbc mode 289 * version 2: uses 64 multikey scheme with lmk IV generator 290 * version 3: the same as version 2 with additional IV seed 291 * (it uses 65 keys, last key is used as IV seed) 292 * 293 * tcw: Compatible implementation of the block chaining mode used 294 * by the TrueCrypt device encryption system (prior to version 4.1). 295 * For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat 296 * It operates on full 512 byte sectors and uses CBC 297 * with an IV derived from initial key and the sector number. 298 * In addition, whitening value is applied on every sector, whitening 299 * is calculated from initial key, sector number and mixed using CRC32. 300 * Note that this encryption scheme is vulnerable to watermarking attacks 301 * and should be used for old compatible containers access only. 302 * 303 * eboiv: Encrypted byte-offset IV (used in Bitlocker in CBC mode) 304 * The IV is encrypted little-endian byte-offset (with the same key 305 * and cipher as the volume). 306 * 307 * elephant: The extended version of eboiv with additional Elephant diffuser 308 * used with Bitlocker CBC mode. 309 * This mode was used in older Windows systems 310 * https://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf 311 */ 312 313 static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, 314 struct dm_crypt_request *dmreq) 315 { 316 memset(iv, 0, cc->iv_size); 317 *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff); 318 319 return 0; 320 } 321 322 static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv, 323 struct dm_crypt_request *dmreq) 324 { 325 memset(iv, 0, cc->iv_size); 326 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 327 328 return 0; 329 } 330 331 static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv, 332 struct dm_crypt_request *dmreq) 333 { 334 memset(iv, 0, cc->iv_size); 335 /* iv_size is at least of size u64; usually it is 16 bytes */ 336 *(__be64 *)&iv[cc->iv_size - sizeof(u64)] = cpu_to_be64(dmreq->iv_sector); 337 338 return 0; 339 } 340 341 static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, 342 struct dm_crypt_request *dmreq) 343 { 344 /* 345 * ESSIV encryption of the IV is now handled by the crypto API, 346 * so just pass the plain sector number here. 347 */ 348 memset(iv, 0, cc->iv_size); 349 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 350 351 return 0; 352 } 353 354 static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, 355 const char *opts) 356 { 357 unsigned bs; 358 int log; 359 360 if (crypt_integrity_aead(cc)) 361 bs = crypto_aead_blocksize(any_tfm_aead(cc)); 362 else 363 bs = crypto_skcipher_blocksize(any_tfm(cc)); 364 log = ilog2(bs); 365 366 /* we need to calculate how far we must shift the sector count 367 * to get the cipher block count, we use this shift in _gen */ 368 369 if (1 << log != bs) { 370 ti->error = "cypher blocksize is not a power of 2"; 371 return -EINVAL; 372 } 373 374 if (log > 9) { 375 ti->error = "cypher blocksize is > 512"; 376 return -EINVAL; 377 } 378 379 cc->iv_gen_private.benbi.shift = 9 - log; 380 381 return 0; 382 } 383 384 static void crypt_iv_benbi_dtr(struct crypt_config *cc) 385 { 386 } 387 388 static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, 389 struct dm_crypt_request *dmreq) 390 { 391 __be64 val; 392 393 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ 394 395 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1); 396 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); 397 398 return 0; 399 } 400 401 static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, 402 struct dm_crypt_request *dmreq) 403 { 404 memset(iv, 0, cc->iv_size); 405 406 return 0; 407 } 408 409 static void crypt_iv_lmk_dtr(struct crypt_config *cc) 410 { 411 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 412 413 if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm)) 414 crypto_free_shash(lmk->hash_tfm); 415 lmk->hash_tfm = NULL; 416 417 kfree_sensitive(lmk->seed); 418 lmk->seed = NULL; 419 } 420 421 static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti, 422 const char *opts) 423 { 424 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 425 426 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 427 ti->error = "Unsupported sector size for LMK"; 428 return -EINVAL; 429 } 430 431 lmk->hash_tfm = crypto_alloc_shash("md5", 0, 432 CRYPTO_ALG_ALLOCATES_MEMORY); 433 if (IS_ERR(lmk->hash_tfm)) { 434 ti->error = "Error initializing LMK hash"; 435 return PTR_ERR(lmk->hash_tfm); 436 } 437 438 /* No seed in LMK version 2 */ 439 if (cc->key_parts == cc->tfms_count) { 440 lmk->seed = NULL; 441 return 0; 442 } 443 444 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL); 445 if (!lmk->seed) { 446 crypt_iv_lmk_dtr(cc); 447 ti->error = "Error kmallocing seed storage in LMK"; 448 return -ENOMEM; 449 } 450 451 return 0; 452 } 453 454 static int crypt_iv_lmk_init(struct crypt_config *cc) 455 { 456 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 457 int subkey_size = cc->key_size / cc->key_parts; 458 459 /* LMK seed is on the position of LMK_KEYS + 1 key */ 460 if (lmk->seed) 461 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size), 462 crypto_shash_digestsize(lmk->hash_tfm)); 463 464 return 0; 465 } 466 467 static int crypt_iv_lmk_wipe(struct crypt_config *cc) 468 { 469 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 470 471 if (lmk->seed) 472 memset(lmk->seed, 0, LMK_SEED_SIZE); 473 474 return 0; 475 } 476 477 static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv, 478 struct dm_crypt_request *dmreq, 479 u8 *data) 480 { 481 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 482 SHASH_DESC_ON_STACK(desc, lmk->hash_tfm); 483 struct md5_state md5state; 484 __le32 buf[4]; 485 int i, r; 486 487 desc->tfm = lmk->hash_tfm; 488 489 r = crypto_shash_init(desc); 490 if (r) 491 return r; 492 493 if (lmk->seed) { 494 r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE); 495 if (r) 496 return r; 497 } 498 499 /* Sector is always 512B, block size 16, add data of blocks 1-31 */ 500 r = crypto_shash_update(desc, data + 16, 16 * 31); 501 if (r) 502 return r; 503 504 /* Sector is cropped to 56 bits here */ 505 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF); 506 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000); 507 buf[2] = cpu_to_le32(4024); 508 buf[3] = 0; 509 r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf)); 510 if (r) 511 return r; 512 513 /* No MD5 padding here */ 514 r = crypto_shash_export(desc, &md5state); 515 if (r) 516 return r; 517 518 for (i = 0; i < MD5_HASH_WORDS; i++) 519 __cpu_to_le32s(&md5state.hash[i]); 520 memcpy(iv, &md5state.hash, cc->iv_size); 521 522 return 0; 523 } 524 525 static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv, 526 struct dm_crypt_request *dmreq) 527 { 528 struct scatterlist *sg; 529 u8 *src; 530 int r = 0; 531 532 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 533 sg = crypt_get_sg_data(cc, dmreq->sg_in); 534 src = kmap_atomic(sg_page(sg)); 535 r = crypt_iv_lmk_one(cc, iv, dmreq, src + sg->offset); 536 kunmap_atomic(src); 537 } else 538 memset(iv, 0, cc->iv_size); 539 540 return r; 541 } 542 543 static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv, 544 struct dm_crypt_request *dmreq) 545 { 546 struct scatterlist *sg; 547 u8 *dst; 548 int r; 549 550 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) 551 return 0; 552 553 sg = crypt_get_sg_data(cc, dmreq->sg_out); 554 dst = kmap_atomic(sg_page(sg)); 555 r = crypt_iv_lmk_one(cc, iv, dmreq, dst + sg->offset); 556 557 /* Tweak the first block of plaintext sector */ 558 if (!r) 559 crypto_xor(dst + sg->offset, iv, cc->iv_size); 560 561 kunmap_atomic(dst); 562 return r; 563 } 564 565 static void crypt_iv_tcw_dtr(struct crypt_config *cc) 566 { 567 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 568 569 kfree_sensitive(tcw->iv_seed); 570 tcw->iv_seed = NULL; 571 kfree_sensitive(tcw->whitening); 572 tcw->whitening = NULL; 573 574 if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm)) 575 crypto_free_shash(tcw->crc32_tfm); 576 tcw->crc32_tfm = NULL; 577 } 578 579 static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti, 580 const char *opts) 581 { 582 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 583 584 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 585 ti->error = "Unsupported sector size for TCW"; 586 return -EINVAL; 587 } 588 589 if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) { 590 ti->error = "Wrong key size for TCW"; 591 return -EINVAL; 592 } 593 594 tcw->crc32_tfm = crypto_alloc_shash("crc32", 0, 595 CRYPTO_ALG_ALLOCATES_MEMORY); 596 if (IS_ERR(tcw->crc32_tfm)) { 597 ti->error = "Error initializing CRC32 in TCW"; 598 return PTR_ERR(tcw->crc32_tfm); 599 } 600 601 tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL); 602 tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL); 603 if (!tcw->iv_seed || !tcw->whitening) { 604 crypt_iv_tcw_dtr(cc); 605 ti->error = "Error allocating seed storage in TCW"; 606 return -ENOMEM; 607 } 608 609 return 0; 610 } 611 612 static int crypt_iv_tcw_init(struct crypt_config *cc) 613 { 614 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 615 int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE; 616 617 memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size); 618 memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size], 619 TCW_WHITENING_SIZE); 620 621 return 0; 622 } 623 624 static int crypt_iv_tcw_wipe(struct crypt_config *cc) 625 { 626 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 627 628 memset(tcw->iv_seed, 0, cc->iv_size); 629 memset(tcw->whitening, 0, TCW_WHITENING_SIZE); 630 631 return 0; 632 } 633 634 static int crypt_iv_tcw_whitening(struct crypt_config *cc, 635 struct dm_crypt_request *dmreq, 636 u8 *data) 637 { 638 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 639 __le64 sector = cpu_to_le64(dmreq->iv_sector); 640 u8 buf[TCW_WHITENING_SIZE]; 641 SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm); 642 int i, r; 643 644 /* xor whitening with sector number */ 645 crypto_xor_cpy(buf, tcw->whitening, (u8 *)§or, 8); 646 crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)§or, 8); 647 648 /* calculate crc32 for every 32bit part and xor it */ 649 desc->tfm = tcw->crc32_tfm; 650 for (i = 0; i < 4; i++) { 651 r = crypto_shash_init(desc); 652 if (r) 653 goto out; 654 r = crypto_shash_update(desc, &buf[i * 4], 4); 655 if (r) 656 goto out; 657 r = crypto_shash_final(desc, &buf[i * 4]); 658 if (r) 659 goto out; 660 } 661 crypto_xor(&buf[0], &buf[12], 4); 662 crypto_xor(&buf[4], &buf[8], 4); 663 664 /* apply whitening (8 bytes) to whole sector */ 665 for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++) 666 crypto_xor(data + i * 8, buf, 8); 667 out: 668 memzero_explicit(buf, sizeof(buf)); 669 return r; 670 } 671 672 static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv, 673 struct dm_crypt_request *dmreq) 674 { 675 struct scatterlist *sg; 676 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 677 __le64 sector = cpu_to_le64(dmreq->iv_sector); 678 u8 *src; 679 int r = 0; 680 681 /* Remove whitening from ciphertext */ 682 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 683 sg = crypt_get_sg_data(cc, dmreq->sg_in); 684 src = kmap_atomic(sg_page(sg)); 685 r = crypt_iv_tcw_whitening(cc, dmreq, src + sg->offset); 686 kunmap_atomic(src); 687 } 688 689 /* Calculate IV */ 690 crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)§or, 8); 691 if (cc->iv_size > 8) 692 crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)§or, 693 cc->iv_size - 8); 694 695 return r; 696 } 697 698 static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv, 699 struct dm_crypt_request *dmreq) 700 { 701 struct scatterlist *sg; 702 u8 *dst; 703 int r; 704 705 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 706 return 0; 707 708 /* Apply whitening on ciphertext */ 709 sg = crypt_get_sg_data(cc, dmreq->sg_out); 710 dst = kmap_atomic(sg_page(sg)); 711 r = crypt_iv_tcw_whitening(cc, dmreq, dst + sg->offset); 712 kunmap_atomic(dst); 713 714 return r; 715 } 716 717 static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv, 718 struct dm_crypt_request *dmreq) 719 { 720 /* Used only for writes, there must be an additional space to store IV */ 721 get_random_bytes(iv, cc->iv_size); 722 return 0; 723 } 724 725 static int crypt_iv_eboiv_ctr(struct crypt_config *cc, struct dm_target *ti, 726 const char *opts) 727 { 728 if (crypt_integrity_aead(cc)) { 729 ti->error = "AEAD transforms not supported for EBOIV"; 730 return -EINVAL; 731 } 732 733 if (crypto_skcipher_blocksize(any_tfm(cc)) != cc->iv_size) { 734 ti->error = "Block size of EBOIV cipher does " 735 "not match IV size of block cipher"; 736 return -EINVAL; 737 } 738 739 return 0; 740 } 741 742 static int crypt_iv_eboiv_gen(struct crypt_config *cc, u8 *iv, 743 struct dm_crypt_request *dmreq) 744 { 745 u8 buf[MAX_CIPHER_BLOCKSIZE] __aligned(__alignof__(__le64)); 746 struct skcipher_request *req; 747 struct scatterlist src, dst; 748 DECLARE_CRYPTO_WAIT(wait); 749 int err; 750 751 req = skcipher_request_alloc(any_tfm(cc), GFP_NOIO); 752 if (!req) 753 return -ENOMEM; 754 755 memset(buf, 0, cc->iv_size); 756 *(__le64 *)buf = cpu_to_le64(dmreq->iv_sector * cc->sector_size); 757 758 sg_init_one(&src, page_address(ZERO_PAGE(0)), cc->iv_size); 759 sg_init_one(&dst, iv, cc->iv_size); 760 skcipher_request_set_crypt(req, &src, &dst, cc->iv_size, buf); 761 skcipher_request_set_callback(req, 0, crypto_req_done, &wait); 762 err = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 763 skcipher_request_free(req); 764 765 return err; 766 } 767 768 static void crypt_iv_elephant_dtr(struct crypt_config *cc) 769 { 770 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 771 772 crypto_free_skcipher(elephant->tfm); 773 elephant->tfm = NULL; 774 } 775 776 static int crypt_iv_elephant_ctr(struct crypt_config *cc, struct dm_target *ti, 777 const char *opts) 778 { 779 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 780 int r; 781 782 elephant->tfm = crypto_alloc_skcipher("ecb(aes)", 0, 783 CRYPTO_ALG_ALLOCATES_MEMORY); 784 if (IS_ERR(elephant->tfm)) { 785 r = PTR_ERR(elephant->tfm); 786 elephant->tfm = NULL; 787 return r; 788 } 789 790 r = crypt_iv_eboiv_ctr(cc, ti, NULL); 791 if (r) 792 crypt_iv_elephant_dtr(cc); 793 return r; 794 } 795 796 static void diffuser_disk_to_cpu(u32 *d, size_t n) 797 { 798 #ifndef __LITTLE_ENDIAN 799 int i; 800 801 for (i = 0; i < n; i++) 802 d[i] = le32_to_cpu((__le32)d[i]); 803 #endif 804 } 805 806 static void diffuser_cpu_to_disk(__le32 *d, size_t n) 807 { 808 #ifndef __LITTLE_ENDIAN 809 int i; 810 811 for (i = 0; i < n; i++) 812 d[i] = cpu_to_le32((u32)d[i]); 813 #endif 814 } 815 816 static void diffuser_a_decrypt(u32 *d, size_t n) 817 { 818 int i, i1, i2, i3; 819 820 for (i = 0; i < 5; i++) { 821 i1 = 0; 822 i2 = n - 2; 823 i3 = n - 5; 824 825 while (i1 < (n - 1)) { 826 d[i1] += d[i2] ^ (d[i3] << 9 | d[i3] >> 23); 827 i1++; i2++; i3++; 828 829 if (i3 >= n) 830 i3 -= n; 831 832 d[i1] += d[i2] ^ d[i3]; 833 i1++; i2++; i3++; 834 835 if (i2 >= n) 836 i2 -= n; 837 838 d[i1] += d[i2] ^ (d[i3] << 13 | d[i3] >> 19); 839 i1++; i2++; i3++; 840 841 d[i1] += d[i2] ^ d[i3]; 842 i1++; i2++; i3++; 843 } 844 } 845 } 846 847 static void diffuser_a_encrypt(u32 *d, size_t n) 848 { 849 int i, i1, i2, i3; 850 851 for (i = 0; i < 5; i++) { 852 i1 = n - 1; 853 i2 = n - 2 - 1; 854 i3 = n - 5 - 1; 855 856 while (i1 > 0) { 857 d[i1] -= d[i2] ^ d[i3]; 858 i1--; i2--; i3--; 859 860 d[i1] -= d[i2] ^ (d[i3] << 13 | d[i3] >> 19); 861 i1--; i2--; i3--; 862 863 if (i2 < 0) 864 i2 += n; 865 866 d[i1] -= d[i2] ^ d[i3]; 867 i1--; i2--; i3--; 868 869 if (i3 < 0) 870 i3 += n; 871 872 d[i1] -= d[i2] ^ (d[i3] << 9 | d[i3] >> 23); 873 i1--; i2--; i3--; 874 } 875 } 876 } 877 878 static void diffuser_b_decrypt(u32 *d, size_t n) 879 { 880 int i, i1, i2, i3; 881 882 for (i = 0; i < 3; i++) { 883 i1 = 0; 884 i2 = 2; 885 i3 = 5; 886 887 while (i1 < (n - 1)) { 888 d[i1] += d[i2] ^ d[i3]; 889 i1++; i2++; i3++; 890 891 d[i1] += d[i2] ^ (d[i3] << 10 | d[i3] >> 22); 892 i1++; i2++; i3++; 893 894 if (i2 >= n) 895 i2 -= n; 896 897 d[i1] += d[i2] ^ d[i3]; 898 i1++; i2++; i3++; 899 900 if (i3 >= n) 901 i3 -= n; 902 903 d[i1] += d[i2] ^ (d[i3] << 25 | d[i3] >> 7); 904 i1++; i2++; i3++; 905 } 906 } 907 } 908 909 static void diffuser_b_encrypt(u32 *d, size_t n) 910 { 911 int i, i1, i2, i3; 912 913 for (i = 0; i < 3; i++) { 914 i1 = n - 1; 915 i2 = 2 - 1; 916 i3 = 5 - 1; 917 918 while (i1 > 0) { 919 d[i1] -= d[i2] ^ (d[i3] << 25 | d[i3] >> 7); 920 i1--; i2--; i3--; 921 922 if (i3 < 0) 923 i3 += n; 924 925 d[i1] -= d[i2] ^ d[i3]; 926 i1--; i2--; i3--; 927 928 if (i2 < 0) 929 i2 += n; 930 931 d[i1] -= d[i2] ^ (d[i3] << 10 | d[i3] >> 22); 932 i1--; i2--; i3--; 933 934 d[i1] -= d[i2] ^ d[i3]; 935 i1--; i2--; i3--; 936 } 937 } 938 } 939 940 static int crypt_iv_elephant(struct crypt_config *cc, struct dm_crypt_request *dmreq) 941 { 942 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 943 u8 *es, *ks, *data, *data2, *data_offset; 944 struct skcipher_request *req; 945 struct scatterlist *sg, *sg2, src, dst; 946 DECLARE_CRYPTO_WAIT(wait); 947 int i, r; 948 949 req = skcipher_request_alloc(elephant->tfm, GFP_NOIO); 950 es = kzalloc(16, GFP_NOIO); /* Key for AES */ 951 ks = kzalloc(32, GFP_NOIO); /* Elephant sector key */ 952 953 if (!req || !es || !ks) { 954 r = -ENOMEM; 955 goto out; 956 } 957 958 *(__le64 *)es = cpu_to_le64(dmreq->iv_sector * cc->sector_size); 959 960 /* E(Ks, e(s)) */ 961 sg_init_one(&src, es, 16); 962 sg_init_one(&dst, ks, 16); 963 skcipher_request_set_crypt(req, &src, &dst, 16, NULL); 964 skcipher_request_set_callback(req, 0, crypto_req_done, &wait); 965 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 966 if (r) 967 goto out; 968 969 /* E(Ks, e'(s)) */ 970 es[15] = 0x80; 971 sg_init_one(&dst, &ks[16], 16); 972 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 973 if (r) 974 goto out; 975 976 sg = crypt_get_sg_data(cc, dmreq->sg_out); 977 data = kmap_atomic(sg_page(sg)); 978 data_offset = data + sg->offset; 979 980 /* Cannot modify original bio, copy to sg_out and apply Elephant to it */ 981 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 982 sg2 = crypt_get_sg_data(cc, dmreq->sg_in); 983 data2 = kmap_atomic(sg_page(sg2)); 984 memcpy(data_offset, data2 + sg2->offset, cc->sector_size); 985 kunmap_atomic(data2); 986 } 987 988 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 989 diffuser_disk_to_cpu((u32*)data_offset, cc->sector_size / sizeof(u32)); 990 diffuser_b_decrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 991 diffuser_a_decrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 992 diffuser_cpu_to_disk((__le32*)data_offset, cc->sector_size / sizeof(u32)); 993 } 994 995 for (i = 0; i < (cc->sector_size / 32); i++) 996 crypto_xor(data_offset + i * 32, ks, 32); 997 998 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 999 diffuser_disk_to_cpu((u32*)data_offset, cc->sector_size / sizeof(u32)); 1000 diffuser_a_encrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 1001 diffuser_b_encrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 1002 diffuser_cpu_to_disk((__le32*)data_offset, cc->sector_size / sizeof(u32)); 1003 } 1004 1005 kunmap_atomic(data); 1006 out: 1007 kfree_sensitive(ks); 1008 kfree_sensitive(es); 1009 skcipher_request_free(req); 1010 return r; 1011 } 1012 1013 static int crypt_iv_elephant_gen(struct crypt_config *cc, u8 *iv, 1014 struct dm_crypt_request *dmreq) 1015 { 1016 int r; 1017 1018 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 1019 r = crypt_iv_elephant(cc, dmreq); 1020 if (r) 1021 return r; 1022 } 1023 1024 return crypt_iv_eboiv_gen(cc, iv, dmreq); 1025 } 1026 1027 static int crypt_iv_elephant_post(struct crypt_config *cc, u8 *iv, 1028 struct dm_crypt_request *dmreq) 1029 { 1030 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 1031 return crypt_iv_elephant(cc, dmreq); 1032 1033 return 0; 1034 } 1035 1036 static int crypt_iv_elephant_init(struct crypt_config *cc) 1037 { 1038 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 1039 int key_offset = cc->key_size - cc->key_extra_size; 1040 1041 return crypto_skcipher_setkey(elephant->tfm, &cc->key[key_offset], cc->key_extra_size); 1042 } 1043 1044 static int crypt_iv_elephant_wipe(struct crypt_config *cc) 1045 { 1046 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 1047 u8 key[ELEPHANT_MAX_KEY_SIZE]; 1048 1049 memset(key, 0, cc->key_extra_size); 1050 return crypto_skcipher_setkey(elephant->tfm, key, cc->key_extra_size); 1051 } 1052 1053 static const struct crypt_iv_operations crypt_iv_plain_ops = { 1054 .generator = crypt_iv_plain_gen 1055 }; 1056 1057 static const struct crypt_iv_operations crypt_iv_plain64_ops = { 1058 .generator = crypt_iv_plain64_gen 1059 }; 1060 1061 static const struct crypt_iv_operations crypt_iv_plain64be_ops = { 1062 .generator = crypt_iv_plain64be_gen 1063 }; 1064 1065 static const struct crypt_iv_operations crypt_iv_essiv_ops = { 1066 .generator = crypt_iv_essiv_gen 1067 }; 1068 1069 static const struct crypt_iv_operations crypt_iv_benbi_ops = { 1070 .ctr = crypt_iv_benbi_ctr, 1071 .dtr = crypt_iv_benbi_dtr, 1072 .generator = crypt_iv_benbi_gen 1073 }; 1074 1075 static const struct crypt_iv_operations crypt_iv_null_ops = { 1076 .generator = crypt_iv_null_gen 1077 }; 1078 1079 static const struct crypt_iv_operations crypt_iv_lmk_ops = { 1080 .ctr = crypt_iv_lmk_ctr, 1081 .dtr = crypt_iv_lmk_dtr, 1082 .init = crypt_iv_lmk_init, 1083 .wipe = crypt_iv_lmk_wipe, 1084 .generator = crypt_iv_lmk_gen, 1085 .post = crypt_iv_lmk_post 1086 }; 1087 1088 static const struct crypt_iv_operations crypt_iv_tcw_ops = { 1089 .ctr = crypt_iv_tcw_ctr, 1090 .dtr = crypt_iv_tcw_dtr, 1091 .init = crypt_iv_tcw_init, 1092 .wipe = crypt_iv_tcw_wipe, 1093 .generator = crypt_iv_tcw_gen, 1094 .post = crypt_iv_tcw_post 1095 }; 1096 1097 static const struct crypt_iv_operations crypt_iv_random_ops = { 1098 .generator = crypt_iv_random_gen 1099 }; 1100 1101 static const struct crypt_iv_operations crypt_iv_eboiv_ops = { 1102 .ctr = crypt_iv_eboiv_ctr, 1103 .generator = crypt_iv_eboiv_gen 1104 }; 1105 1106 static const struct crypt_iv_operations crypt_iv_elephant_ops = { 1107 .ctr = crypt_iv_elephant_ctr, 1108 .dtr = crypt_iv_elephant_dtr, 1109 .init = crypt_iv_elephant_init, 1110 .wipe = crypt_iv_elephant_wipe, 1111 .generator = crypt_iv_elephant_gen, 1112 .post = crypt_iv_elephant_post 1113 }; 1114 1115 /* 1116 * Integrity extensions 1117 */ 1118 static bool crypt_integrity_aead(struct crypt_config *cc) 1119 { 1120 return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 1121 } 1122 1123 static bool crypt_integrity_hmac(struct crypt_config *cc) 1124 { 1125 return crypt_integrity_aead(cc) && cc->key_mac_size; 1126 } 1127 1128 /* Get sg containing data */ 1129 static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 1130 struct scatterlist *sg) 1131 { 1132 if (unlikely(crypt_integrity_aead(cc))) 1133 return &sg[2]; 1134 1135 return sg; 1136 } 1137 1138 static int dm_crypt_integrity_io_alloc(struct dm_crypt_io *io, struct bio *bio) 1139 { 1140 struct bio_integrity_payload *bip; 1141 unsigned int tag_len; 1142 int ret; 1143 1144 if (!bio_sectors(bio) || !io->cc->on_disk_tag_size) 1145 return 0; 1146 1147 bip = bio_integrity_alloc(bio, GFP_NOIO, 1); 1148 if (IS_ERR(bip)) 1149 return PTR_ERR(bip); 1150 1151 tag_len = io->cc->on_disk_tag_size * (bio_sectors(bio) >> io->cc->sector_shift); 1152 1153 bip->bip_iter.bi_size = tag_len; 1154 bip->bip_iter.bi_sector = io->cc->start + io->sector; 1155 1156 ret = bio_integrity_add_page(bio, virt_to_page(io->integrity_metadata), 1157 tag_len, offset_in_page(io->integrity_metadata)); 1158 if (unlikely(ret != tag_len)) 1159 return -ENOMEM; 1160 1161 return 0; 1162 } 1163 1164 static int crypt_integrity_ctr(struct crypt_config *cc, struct dm_target *ti) 1165 { 1166 #ifdef CONFIG_BLK_DEV_INTEGRITY 1167 struct blk_integrity *bi = blk_get_integrity(cc->dev->bdev->bd_disk); 1168 struct mapped_device *md = dm_table_get_md(ti->table); 1169 1170 /* From now we require underlying device with our integrity profile */ 1171 if (!bi || strcasecmp(bi->profile->name, "DM-DIF-EXT-TAG")) { 1172 ti->error = "Integrity profile not supported."; 1173 return -EINVAL; 1174 } 1175 1176 if (bi->tag_size != cc->on_disk_tag_size || 1177 bi->tuple_size != cc->on_disk_tag_size) { 1178 ti->error = "Integrity profile tag size mismatch."; 1179 return -EINVAL; 1180 } 1181 if (1 << bi->interval_exp != cc->sector_size) { 1182 ti->error = "Integrity profile sector size mismatch."; 1183 return -EINVAL; 1184 } 1185 1186 if (crypt_integrity_aead(cc)) { 1187 cc->integrity_tag_size = cc->on_disk_tag_size - cc->integrity_iv_size; 1188 DMDEBUG("%s: Integrity AEAD, tag size %u, IV size %u.", dm_device_name(md), 1189 cc->integrity_tag_size, cc->integrity_iv_size); 1190 1191 if (crypto_aead_setauthsize(any_tfm_aead(cc), cc->integrity_tag_size)) { 1192 ti->error = "Integrity AEAD auth tag size is not supported."; 1193 return -EINVAL; 1194 } 1195 } else if (cc->integrity_iv_size) 1196 DMDEBUG("%s: Additional per-sector space %u bytes for IV.", dm_device_name(md), 1197 cc->integrity_iv_size); 1198 1199 if ((cc->integrity_tag_size + cc->integrity_iv_size) != bi->tag_size) { 1200 ti->error = "Not enough space for integrity tag in the profile."; 1201 return -EINVAL; 1202 } 1203 1204 return 0; 1205 #else 1206 ti->error = "Integrity profile not supported."; 1207 return -EINVAL; 1208 #endif 1209 } 1210 1211 static void crypt_convert_init(struct crypt_config *cc, 1212 struct convert_context *ctx, 1213 struct bio *bio_out, struct bio *bio_in, 1214 sector_t sector) 1215 { 1216 ctx->bio_in = bio_in; 1217 ctx->bio_out = bio_out; 1218 if (bio_in) 1219 ctx->iter_in = bio_in->bi_iter; 1220 if (bio_out) 1221 ctx->iter_out = bio_out->bi_iter; 1222 ctx->cc_sector = sector + cc->iv_offset; 1223 init_completion(&ctx->restart); 1224 } 1225 1226 static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc, 1227 void *req) 1228 { 1229 return (struct dm_crypt_request *)((char *)req + cc->dmreq_start); 1230 } 1231 1232 static void *req_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq) 1233 { 1234 return (void *)((char *)dmreq - cc->dmreq_start); 1235 } 1236 1237 static u8 *iv_of_dmreq(struct crypt_config *cc, 1238 struct dm_crypt_request *dmreq) 1239 { 1240 if (crypt_integrity_aead(cc)) 1241 return (u8 *)ALIGN((unsigned long)(dmreq + 1), 1242 crypto_aead_alignmask(any_tfm_aead(cc)) + 1); 1243 else 1244 return (u8 *)ALIGN((unsigned long)(dmreq + 1), 1245 crypto_skcipher_alignmask(any_tfm(cc)) + 1); 1246 } 1247 1248 static u8 *org_iv_of_dmreq(struct crypt_config *cc, 1249 struct dm_crypt_request *dmreq) 1250 { 1251 return iv_of_dmreq(cc, dmreq) + cc->iv_size; 1252 } 1253 1254 static __le64 *org_sector_of_dmreq(struct crypt_config *cc, 1255 struct dm_crypt_request *dmreq) 1256 { 1257 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + cc->iv_size; 1258 return (__le64 *) ptr; 1259 } 1260 1261 static unsigned int *org_tag_of_dmreq(struct crypt_config *cc, 1262 struct dm_crypt_request *dmreq) 1263 { 1264 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + 1265 cc->iv_size + sizeof(uint64_t); 1266 return (unsigned int*)ptr; 1267 } 1268 1269 static void *tag_from_dmreq(struct crypt_config *cc, 1270 struct dm_crypt_request *dmreq) 1271 { 1272 struct convert_context *ctx = dmreq->ctx; 1273 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 1274 1275 return &io->integrity_metadata[*org_tag_of_dmreq(cc, dmreq) * 1276 cc->on_disk_tag_size]; 1277 } 1278 1279 static void *iv_tag_from_dmreq(struct crypt_config *cc, 1280 struct dm_crypt_request *dmreq) 1281 { 1282 return tag_from_dmreq(cc, dmreq) + cc->integrity_tag_size; 1283 } 1284 1285 static int crypt_convert_block_aead(struct crypt_config *cc, 1286 struct convert_context *ctx, 1287 struct aead_request *req, 1288 unsigned int tag_offset) 1289 { 1290 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1291 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1292 struct dm_crypt_request *dmreq; 1293 u8 *iv, *org_iv, *tag_iv, *tag; 1294 __le64 *sector; 1295 int r = 0; 1296 1297 BUG_ON(cc->integrity_iv_size && cc->integrity_iv_size != cc->iv_size); 1298 1299 /* Reject unexpected unaligned bio. */ 1300 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1301 return -EIO; 1302 1303 dmreq = dmreq_of_req(cc, req); 1304 dmreq->iv_sector = ctx->cc_sector; 1305 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1306 dmreq->iv_sector >>= cc->sector_shift; 1307 dmreq->ctx = ctx; 1308 1309 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1310 1311 sector = org_sector_of_dmreq(cc, dmreq); 1312 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1313 1314 iv = iv_of_dmreq(cc, dmreq); 1315 org_iv = org_iv_of_dmreq(cc, dmreq); 1316 tag = tag_from_dmreq(cc, dmreq); 1317 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1318 1319 /* AEAD request: 1320 * |----- AAD -------|------ DATA -------|-- AUTH TAG --| 1321 * | (authenticated) | (auth+encryption) | | 1322 * | sector_LE | IV | sector in/out | tag in/out | 1323 */ 1324 sg_init_table(dmreq->sg_in, 4); 1325 sg_set_buf(&dmreq->sg_in[0], sector, sizeof(uint64_t)); 1326 sg_set_buf(&dmreq->sg_in[1], org_iv, cc->iv_size); 1327 sg_set_page(&dmreq->sg_in[2], bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1328 sg_set_buf(&dmreq->sg_in[3], tag, cc->integrity_tag_size); 1329 1330 sg_init_table(dmreq->sg_out, 4); 1331 sg_set_buf(&dmreq->sg_out[0], sector, sizeof(uint64_t)); 1332 sg_set_buf(&dmreq->sg_out[1], org_iv, cc->iv_size); 1333 sg_set_page(&dmreq->sg_out[2], bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1334 sg_set_buf(&dmreq->sg_out[3], tag, cc->integrity_tag_size); 1335 1336 if (cc->iv_gen_ops) { 1337 /* For READs use IV stored in integrity metadata */ 1338 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1339 memcpy(org_iv, tag_iv, cc->iv_size); 1340 } else { 1341 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1342 if (r < 0) 1343 return r; 1344 /* Store generated IV in integrity metadata */ 1345 if (cc->integrity_iv_size) 1346 memcpy(tag_iv, org_iv, cc->iv_size); 1347 } 1348 /* Working copy of IV, to be modified in crypto API */ 1349 memcpy(iv, org_iv, cc->iv_size); 1350 } 1351 1352 aead_request_set_ad(req, sizeof(uint64_t) + cc->iv_size); 1353 if (bio_data_dir(ctx->bio_in) == WRITE) { 1354 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out, 1355 cc->sector_size, iv); 1356 r = crypto_aead_encrypt(req); 1357 if (cc->integrity_tag_size + cc->integrity_iv_size != cc->on_disk_tag_size) 1358 memset(tag + cc->integrity_tag_size + cc->integrity_iv_size, 0, 1359 cc->on_disk_tag_size - (cc->integrity_tag_size + cc->integrity_iv_size)); 1360 } else { 1361 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out, 1362 cc->sector_size + cc->integrity_tag_size, iv); 1363 r = crypto_aead_decrypt(req); 1364 } 1365 1366 if (r == -EBADMSG) { 1367 char b[BDEVNAME_SIZE]; 1368 sector_t s = le64_to_cpu(*sector); 1369 1370 DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu", 1371 bio_devname(ctx->bio_in, b), s); 1372 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead", 1373 ctx->bio_in, s, 0); 1374 } 1375 1376 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1377 r = cc->iv_gen_ops->post(cc, org_iv, dmreq); 1378 1379 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1380 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1381 1382 return r; 1383 } 1384 1385 static int crypt_convert_block_skcipher(struct crypt_config *cc, 1386 struct convert_context *ctx, 1387 struct skcipher_request *req, 1388 unsigned int tag_offset) 1389 { 1390 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1391 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1392 struct scatterlist *sg_in, *sg_out; 1393 struct dm_crypt_request *dmreq; 1394 u8 *iv, *org_iv, *tag_iv; 1395 __le64 *sector; 1396 int r = 0; 1397 1398 /* Reject unexpected unaligned bio. */ 1399 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1400 return -EIO; 1401 1402 dmreq = dmreq_of_req(cc, req); 1403 dmreq->iv_sector = ctx->cc_sector; 1404 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1405 dmreq->iv_sector >>= cc->sector_shift; 1406 dmreq->ctx = ctx; 1407 1408 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1409 1410 iv = iv_of_dmreq(cc, dmreq); 1411 org_iv = org_iv_of_dmreq(cc, dmreq); 1412 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1413 1414 sector = org_sector_of_dmreq(cc, dmreq); 1415 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1416 1417 /* For skcipher we use only the first sg item */ 1418 sg_in = &dmreq->sg_in[0]; 1419 sg_out = &dmreq->sg_out[0]; 1420 1421 sg_init_table(sg_in, 1); 1422 sg_set_page(sg_in, bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1423 1424 sg_init_table(sg_out, 1); 1425 sg_set_page(sg_out, bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1426 1427 if (cc->iv_gen_ops) { 1428 /* For READs use IV stored in integrity metadata */ 1429 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1430 memcpy(org_iv, tag_iv, cc->integrity_iv_size); 1431 } else { 1432 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1433 if (r < 0) 1434 return r; 1435 /* Data can be already preprocessed in generator */ 1436 if (test_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags)) 1437 sg_in = sg_out; 1438 /* Store generated IV in integrity metadata */ 1439 if (cc->integrity_iv_size) 1440 memcpy(tag_iv, org_iv, cc->integrity_iv_size); 1441 } 1442 /* Working copy of IV, to be modified in crypto API */ 1443 memcpy(iv, org_iv, cc->iv_size); 1444 } 1445 1446 skcipher_request_set_crypt(req, sg_in, sg_out, cc->sector_size, iv); 1447 1448 if (bio_data_dir(ctx->bio_in) == WRITE) 1449 r = crypto_skcipher_encrypt(req); 1450 else 1451 r = crypto_skcipher_decrypt(req); 1452 1453 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1454 r = cc->iv_gen_ops->post(cc, org_iv, dmreq); 1455 1456 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1457 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1458 1459 return r; 1460 } 1461 1462 static void kcryptd_async_done(struct crypto_async_request *async_req, 1463 int error); 1464 1465 static int crypt_alloc_req_skcipher(struct crypt_config *cc, 1466 struct convert_context *ctx) 1467 { 1468 unsigned key_index = ctx->cc_sector & (cc->tfms_count - 1); 1469 1470 if (!ctx->r.req) { 1471 ctx->r.req = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1472 if (!ctx->r.req) 1473 return -ENOMEM; 1474 } 1475 1476 skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]); 1477 1478 /* 1479 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1480 * requests if driver request queue is full. 1481 */ 1482 skcipher_request_set_callback(ctx->r.req, 1483 CRYPTO_TFM_REQ_MAY_BACKLOG, 1484 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req)); 1485 1486 return 0; 1487 } 1488 1489 static int crypt_alloc_req_aead(struct crypt_config *cc, 1490 struct convert_context *ctx) 1491 { 1492 if (!ctx->r.req_aead) { 1493 ctx->r.req_aead = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1494 if (!ctx->r.req_aead) 1495 return -ENOMEM; 1496 } 1497 1498 aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]); 1499 1500 /* 1501 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1502 * requests if driver request queue is full. 1503 */ 1504 aead_request_set_callback(ctx->r.req_aead, 1505 CRYPTO_TFM_REQ_MAY_BACKLOG, 1506 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead)); 1507 1508 return 0; 1509 } 1510 1511 static int crypt_alloc_req(struct crypt_config *cc, 1512 struct convert_context *ctx) 1513 { 1514 if (crypt_integrity_aead(cc)) 1515 return crypt_alloc_req_aead(cc, ctx); 1516 else 1517 return crypt_alloc_req_skcipher(cc, ctx); 1518 } 1519 1520 static void crypt_free_req_skcipher(struct crypt_config *cc, 1521 struct skcipher_request *req, struct bio *base_bio) 1522 { 1523 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1524 1525 if ((struct skcipher_request *)(io + 1) != req) 1526 mempool_free(req, &cc->req_pool); 1527 } 1528 1529 static void crypt_free_req_aead(struct crypt_config *cc, 1530 struct aead_request *req, struct bio *base_bio) 1531 { 1532 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1533 1534 if ((struct aead_request *)(io + 1) != req) 1535 mempool_free(req, &cc->req_pool); 1536 } 1537 1538 static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio) 1539 { 1540 if (crypt_integrity_aead(cc)) 1541 crypt_free_req_aead(cc, req, base_bio); 1542 else 1543 crypt_free_req_skcipher(cc, req, base_bio); 1544 } 1545 1546 /* 1547 * Encrypt / decrypt data from one bio to another one (can be the same one) 1548 */ 1549 static blk_status_t crypt_convert(struct crypt_config *cc, 1550 struct convert_context *ctx, bool atomic, bool reset_pending) 1551 { 1552 unsigned int tag_offset = 0; 1553 unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT; 1554 int r; 1555 1556 /* 1557 * if reset_pending is set we are dealing with the bio for the first time, 1558 * else we're continuing to work on the previous bio, so don't mess with 1559 * the cc_pending counter 1560 */ 1561 if (reset_pending) 1562 atomic_set(&ctx->cc_pending, 1); 1563 1564 while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) { 1565 1566 r = crypt_alloc_req(cc, ctx); 1567 if (r) { 1568 complete(&ctx->restart); 1569 return BLK_STS_DEV_RESOURCE; 1570 } 1571 1572 atomic_inc(&ctx->cc_pending); 1573 1574 if (crypt_integrity_aead(cc)) 1575 r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, tag_offset); 1576 else 1577 r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, tag_offset); 1578 1579 switch (r) { 1580 /* 1581 * The request was queued by a crypto driver 1582 * but the driver request queue is full, let's wait. 1583 */ 1584 case -EBUSY: 1585 if (in_interrupt()) { 1586 if (try_wait_for_completion(&ctx->restart)) { 1587 /* 1588 * we don't have to block to wait for completion, 1589 * so proceed 1590 */ 1591 } else { 1592 /* 1593 * we can't wait for completion without blocking 1594 * exit and continue processing in a workqueue 1595 */ 1596 ctx->r.req = NULL; 1597 ctx->cc_sector += sector_step; 1598 tag_offset++; 1599 return BLK_STS_DEV_RESOURCE; 1600 } 1601 } else { 1602 wait_for_completion(&ctx->restart); 1603 } 1604 reinit_completion(&ctx->restart); 1605 fallthrough; 1606 /* 1607 * The request is queued and processed asynchronously, 1608 * completion function kcryptd_async_done() will be called. 1609 */ 1610 case -EINPROGRESS: 1611 ctx->r.req = NULL; 1612 ctx->cc_sector += sector_step; 1613 tag_offset++; 1614 continue; 1615 /* 1616 * The request was already processed (synchronously). 1617 */ 1618 case 0: 1619 atomic_dec(&ctx->cc_pending); 1620 ctx->cc_sector += sector_step; 1621 tag_offset++; 1622 if (!atomic) 1623 cond_resched(); 1624 continue; 1625 /* 1626 * There was a data integrity error. 1627 */ 1628 case -EBADMSG: 1629 atomic_dec(&ctx->cc_pending); 1630 return BLK_STS_PROTECTION; 1631 /* 1632 * There was an error while processing the request. 1633 */ 1634 default: 1635 atomic_dec(&ctx->cc_pending); 1636 return BLK_STS_IOERR; 1637 } 1638 } 1639 1640 return 0; 1641 } 1642 1643 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone); 1644 1645 /* 1646 * Generate a new unfragmented bio with the given size 1647 * This should never violate the device limitations (but only because 1648 * max_segment_size is being constrained to PAGE_SIZE). 1649 * 1650 * This function may be called concurrently. If we allocate from the mempool 1651 * concurrently, there is a possibility of deadlock. For example, if we have 1652 * mempool of 256 pages, two processes, each wanting 256, pages allocate from 1653 * the mempool concurrently, it may deadlock in a situation where both processes 1654 * have allocated 128 pages and the mempool is exhausted. 1655 * 1656 * In order to avoid this scenario we allocate the pages under a mutex. 1657 * 1658 * In order to not degrade performance with excessive locking, we try 1659 * non-blocking allocations without a mutex first but on failure we fallback 1660 * to blocking allocations with a mutex. 1661 */ 1662 static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size) 1663 { 1664 struct crypt_config *cc = io->cc; 1665 struct bio *clone; 1666 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; 1667 gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM; 1668 unsigned i, len, remaining_size; 1669 struct page *page; 1670 1671 retry: 1672 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1673 mutex_lock(&cc->bio_alloc_lock); 1674 1675 clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, &cc->bs); 1676 if (!clone) 1677 goto out; 1678 1679 clone_init(io, clone); 1680 1681 remaining_size = size; 1682 1683 for (i = 0; i < nr_iovecs; i++) { 1684 page = mempool_alloc(&cc->page_pool, gfp_mask); 1685 if (!page) { 1686 crypt_free_buffer_pages(cc, clone); 1687 bio_put(clone); 1688 gfp_mask |= __GFP_DIRECT_RECLAIM; 1689 goto retry; 1690 } 1691 1692 len = (remaining_size > PAGE_SIZE) ? PAGE_SIZE : remaining_size; 1693 1694 bio_add_page(clone, page, len, 0); 1695 1696 remaining_size -= len; 1697 } 1698 1699 /* Allocate space for integrity tags */ 1700 if (dm_crypt_integrity_io_alloc(io, clone)) { 1701 crypt_free_buffer_pages(cc, clone); 1702 bio_put(clone); 1703 clone = NULL; 1704 } 1705 out: 1706 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1707 mutex_unlock(&cc->bio_alloc_lock); 1708 1709 return clone; 1710 } 1711 1712 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) 1713 { 1714 struct bio_vec *bv; 1715 struct bvec_iter_all iter_all; 1716 1717 bio_for_each_segment_all(bv, clone, iter_all) { 1718 BUG_ON(!bv->bv_page); 1719 mempool_free(bv->bv_page, &cc->page_pool); 1720 } 1721 } 1722 1723 static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc, 1724 struct bio *bio, sector_t sector) 1725 { 1726 io->cc = cc; 1727 io->base_bio = bio; 1728 io->sector = sector; 1729 io->error = 0; 1730 io->ctx.r.req = NULL; 1731 io->integrity_metadata = NULL; 1732 io->integrity_metadata_from_pool = false; 1733 atomic_set(&io->io_pending, 0); 1734 } 1735 1736 static void crypt_inc_pending(struct dm_crypt_io *io) 1737 { 1738 atomic_inc(&io->io_pending); 1739 } 1740 1741 static void kcryptd_io_bio_endio(struct work_struct *work) 1742 { 1743 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 1744 bio_endio(io->base_bio); 1745 } 1746 1747 /* 1748 * One of the bios was finished. Check for completion of 1749 * the whole request and correctly clean up the buffer. 1750 */ 1751 static void crypt_dec_pending(struct dm_crypt_io *io) 1752 { 1753 struct crypt_config *cc = io->cc; 1754 struct bio *base_bio = io->base_bio; 1755 blk_status_t error = io->error; 1756 1757 if (!atomic_dec_and_test(&io->io_pending)) 1758 return; 1759 1760 if (io->ctx.r.req) 1761 crypt_free_req(cc, io->ctx.r.req, base_bio); 1762 1763 if (unlikely(io->integrity_metadata_from_pool)) 1764 mempool_free(io->integrity_metadata, &io->cc->tag_pool); 1765 else 1766 kfree(io->integrity_metadata); 1767 1768 base_bio->bi_status = error; 1769 1770 /* 1771 * If we are running this function from our tasklet, 1772 * we can't call bio_endio() here, because it will call 1773 * clone_endio() from dm.c, which in turn will 1774 * free the current struct dm_crypt_io structure with 1775 * our tasklet. In this case we need to delay bio_endio() 1776 * execution to after the tasklet is done and dequeued. 1777 */ 1778 if (tasklet_trylock(&io->tasklet)) { 1779 tasklet_unlock(&io->tasklet); 1780 bio_endio(base_bio); 1781 return; 1782 } 1783 1784 INIT_WORK(&io->work, kcryptd_io_bio_endio); 1785 queue_work(cc->io_queue, &io->work); 1786 } 1787 1788 /* 1789 * kcryptd/kcryptd_io: 1790 * 1791 * Needed because it would be very unwise to do decryption in an 1792 * interrupt context. 1793 * 1794 * kcryptd performs the actual encryption or decryption. 1795 * 1796 * kcryptd_io performs the IO submission. 1797 * 1798 * They must be separated as otherwise the final stages could be 1799 * starved by new requests which can block in the first stages due 1800 * to memory allocation. 1801 * 1802 * The work is done per CPU global for all dm-crypt instances. 1803 * They should not depend on each other and do not block. 1804 */ 1805 static void crypt_endio(struct bio *clone) 1806 { 1807 struct dm_crypt_io *io = clone->bi_private; 1808 struct crypt_config *cc = io->cc; 1809 unsigned rw = bio_data_dir(clone); 1810 blk_status_t error; 1811 1812 /* 1813 * free the processed pages 1814 */ 1815 if (rw == WRITE) 1816 crypt_free_buffer_pages(cc, clone); 1817 1818 error = clone->bi_status; 1819 bio_put(clone); 1820 1821 if (rw == READ && !error) { 1822 kcryptd_queue_crypt(io); 1823 return; 1824 } 1825 1826 if (unlikely(error)) 1827 io->error = error; 1828 1829 crypt_dec_pending(io); 1830 } 1831 1832 static void clone_init(struct dm_crypt_io *io, struct bio *clone) 1833 { 1834 struct crypt_config *cc = io->cc; 1835 1836 clone->bi_private = io; 1837 clone->bi_end_io = crypt_endio; 1838 bio_set_dev(clone, cc->dev->bdev); 1839 clone->bi_opf = io->base_bio->bi_opf; 1840 } 1841 1842 static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp) 1843 { 1844 struct crypt_config *cc = io->cc; 1845 struct bio *clone; 1846 1847 /* 1848 * We need the original biovec array in order to decrypt 1849 * the whole bio data *afterwards* -- thanks to immutable 1850 * biovecs we don't need to worry about the block layer 1851 * modifying the biovec array; so leverage bio_clone_fast(). 1852 */ 1853 clone = bio_clone_fast(io->base_bio, gfp, &cc->bs); 1854 if (!clone) 1855 return 1; 1856 1857 crypt_inc_pending(io); 1858 1859 clone_init(io, clone); 1860 clone->bi_iter.bi_sector = cc->start + io->sector; 1861 1862 if (dm_crypt_integrity_io_alloc(io, clone)) { 1863 crypt_dec_pending(io); 1864 bio_put(clone); 1865 return 1; 1866 } 1867 1868 submit_bio_noacct(clone); 1869 return 0; 1870 } 1871 1872 static void kcryptd_io_read_work(struct work_struct *work) 1873 { 1874 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 1875 1876 crypt_inc_pending(io); 1877 if (kcryptd_io_read(io, GFP_NOIO)) 1878 io->error = BLK_STS_RESOURCE; 1879 crypt_dec_pending(io); 1880 } 1881 1882 static void kcryptd_queue_read(struct dm_crypt_io *io) 1883 { 1884 struct crypt_config *cc = io->cc; 1885 1886 INIT_WORK(&io->work, kcryptd_io_read_work); 1887 queue_work(cc->io_queue, &io->work); 1888 } 1889 1890 static void kcryptd_io_write(struct dm_crypt_io *io) 1891 { 1892 struct bio *clone = io->ctx.bio_out; 1893 1894 submit_bio_noacct(clone); 1895 } 1896 1897 #define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node) 1898 1899 static int dmcrypt_write(void *data) 1900 { 1901 struct crypt_config *cc = data; 1902 struct dm_crypt_io *io; 1903 1904 while (1) { 1905 struct rb_root write_tree; 1906 struct blk_plug plug; 1907 1908 spin_lock_irq(&cc->write_thread_lock); 1909 continue_locked: 1910 1911 if (!RB_EMPTY_ROOT(&cc->write_tree)) 1912 goto pop_from_list; 1913 1914 set_current_state(TASK_INTERRUPTIBLE); 1915 1916 spin_unlock_irq(&cc->write_thread_lock); 1917 1918 if (unlikely(kthread_should_stop())) { 1919 set_current_state(TASK_RUNNING); 1920 break; 1921 } 1922 1923 schedule(); 1924 1925 set_current_state(TASK_RUNNING); 1926 spin_lock_irq(&cc->write_thread_lock); 1927 goto continue_locked; 1928 1929 pop_from_list: 1930 write_tree = cc->write_tree; 1931 cc->write_tree = RB_ROOT; 1932 spin_unlock_irq(&cc->write_thread_lock); 1933 1934 BUG_ON(rb_parent(write_tree.rb_node)); 1935 1936 /* 1937 * Note: we cannot walk the tree here with rb_next because 1938 * the structures may be freed when kcryptd_io_write is called. 1939 */ 1940 blk_start_plug(&plug); 1941 do { 1942 io = crypt_io_from_node(rb_first(&write_tree)); 1943 rb_erase(&io->rb_node, &write_tree); 1944 kcryptd_io_write(io); 1945 } while (!RB_EMPTY_ROOT(&write_tree)); 1946 blk_finish_plug(&plug); 1947 } 1948 return 0; 1949 } 1950 1951 static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async) 1952 { 1953 struct bio *clone = io->ctx.bio_out; 1954 struct crypt_config *cc = io->cc; 1955 unsigned long flags; 1956 sector_t sector; 1957 struct rb_node **rbp, *parent; 1958 1959 if (unlikely(io->error)) { 1960 crypt_free_buffer_pages(cc, clone); 1961 bio_put(clone); 1962 crypt_dec_pending(io); 1963 return; 1964 } 1965 1966 /* crypt_convert should have filled the clone bio */ 1967 BUG_ON(io->ctx.iter_out.bi_size); 1968 1969 clone->bi_iter.bi_sector = cc->start + io->sector; 1970 1971 if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) || 1972 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) { 1973 submit_bio_noacct(clone); 1974 return; 1975 } 1976 1977 spin_lock_irqsave(&cc->write_thread_lock, flags); 1978 if (RB_EMPTY_ROOT(&cc->write_tree)) 1979 wake_up_process(cc->write_thread); 1980 rbp = &cc->write_tree.rb_node; 1981 parent = NULL; 1982 sector = io->sector; 1983 while (*rbp) { 1984 parent = *rbp; 1985 if (sector < crypt_io_from_node(parent)->sector) 1986 rbp = &(*rbp)->rb_left; 1987 else 1988 rbp = &(*rbp)->rb_right; 1989 } 1990 rb_link_node(&io->rb_node, parent, rbp); 1991 rb_insert_color(&io->rb_node, &cc->write_tree); 1992 spin_unlock_irqrestore(&cc->write_thread_lock, flags); 1993 } 1994 1995 static bool kcryptd_crypt_write_inline(struct crypt_config *cc, 1996 struct convert_context *ctx) 1997 1998 { 1999 if (!test_bit(DM_CRYPT_WRITE_INLINE, &cc->flags)) 2000 return false; 2001 2002 /* 2003 * Note: zone append writes (REQ_OP_ZONE_APPEND) do not have ordering 2004 * constraints so they do not need to be issued inline by 2005 * kcryptd_crypt_write_convert(). 2006 */ 2007 switch (bio_op(ctx->bio_in)) { 2008 case REQ_OP_WRITE: 2009 case REQ_OP_WRITE_ZEROES: 2010 return true; 2011 default: 2012 return false; 2013 } 2014 } 2015 2016 static void kcryptd_crypt_write_continue(struct work_struct *work) 2017 { 2018 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2019 struct crypt_config *cc = io->cc; 2020 struct convert_context *ctx = &io->ctx; 2021 int crypt_finished; 2022 sector_t sector = io->sector; 2023 blk_status_t r; 2024 2025 wait_for_completion(&ctx->restart); 2026 reinit_completion(&ctx->restart); 2027 2028 r = crypt_convert(cc, &io->ctx, true, false); 2029 if (r) 2030 io->error = r; 2031 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2032 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2033 /* Wait for completion signaled by kcryptd_async_done() */ 2034 wait_for_completion(&ctx->restart); 2035 crypt_finished = 1; 2036 } 2037 2038 /* Encryption was already finished, submit io now */ 2039 if (crypt_finished) { 2040 kcryptd_crypt_write_io_submit(io, 0); 2041 io->sector = sector; 2042 } 2043 2044 crypt_dec_pending(io); 2045 } 2046 2047 static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) 2048 { 2049 struct crypt_config *cc = io->cc; 2050 struct convert_context *ctx = &io->ctx; 2051 struct bio *clone; 2052 int crypt_finished; 2053 sector_t sector = io->sector; 2054 blk_status_t r; 2055 2056 /* 2057 * Prevent io from disappearing until this function completes. 2058 */ 2059 crypt_inc_pending(io); 2060 crypt_convert_init(cc, ctx, NULL, io->base_bio, sector); 2061 2062 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size); 2063 if (unlikely(!clone)) { 2064 io->error = BLK_STS_IOERR; 2065 goto dec; 2066 } 2067 2068 io->ctx.bio_out = clone; 2069 io->ctx.iter_out = clone->bi_iter; 2070 2071 sector += bio_sectors(clone); 2072 2073 crypt_inc_pending(io); 2074 r = crypt_convert(cc, ctx, 2075 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags), true); 2076 /* 2077 * Crypto API backlogged the request, because its queue was full 2078 * and we're in softirq context, so continue from a workqueue 2079 * (TODO: is it actually possible to be in softirq in the write path?) 2080 */ 2081 if (r == BLK_STS_DEV_RESOURCE) { 2082 INIT_WORK(&io->work, kcryptd_crypt_write_continue); 2083 queue_work(cc->crypt_queue, &io->work); 2084 return; 2085 } 2086 if (r) 2087 io->error = r; 2088 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2089 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2090 /* Wait for completion signaled by kcryptd_async_done() */ 2091 wait_for_completion(&ctx->restart); 2092 crypt_finished = 1; 2093 } 2094 2095 /* Encryption was already finished, submit io now */ 2096 if (crypt_finished) { 2097 kcryptd_crypt_write_io_submit(io, 0); 2098 io->sector = sector; 2099 } 2100 2101 dec: 2102 crypt_dec_pending(io); 2103 } 2104 2105 static void kcryptd_crypt_read_done(struct dm_crypt_io *io) 2106 { 2107 crypt_dec_pending(io); 2108 } 2109 2110 static void kcryptd_crypt_read_continue(struct work_struct *work) 2111 { 2112 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2113 struct crypt_config *cc = io->cc; 2114 blk_status_t r; 2115 2116 wait_for_completion(&io->ctx.restart); 2117 reinit_completion(&io->ctx.restart); 2118 2119 r = crypt_convert(cc, &io->ctx, true, false); 2120 if (r) 2121 io->error = r; 2122 2123 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2124 kcryptd_crypt_read_done(io); 2125 2126 crypt_dec_pending(io); 2127 } 2128 2129 static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) 2130 { 2131 struct crypt_config *cc = io->cc; 2132 blk_status_t r; 2133 2134 crypt_inc_pending(io); 2135 2136 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, 2137 io->sector); 2138 2139 r = crypt_convert(cc, &io->ctx, 2140 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true); 2141 /* 2142 * Crypto API backlogged the request, because its queue was full 2143 * and we're in softirq context, so continue from a workqueue 2144 */ 2145 if (r == BLK_STS_DEV_RESOURCE) { 2146 INIT_WORK(&io->work, kcryptd_crypt_read_continue); 2147 queue_work(cc->crypt_queue, &io->work); 2148 return; 2149 } 2150 if (r) 2151 io->error = r; 2152 2153 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2154 kcryptd_crypt_read_done(io); 2155 2156 crypt_dec_pending(io); 2157 } 2158 2159 static void kcryptd_async_done(struct crypto_async_request *async_req, 2160 int error) 2161 { 2162 struct dm_crypt_request *dmreq = async_req->data; 2163 struct convert_context *ctx = dmreq->ctx; 2164 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 2165 struct crypt_config *cc = io->cc; 2166 2167 /* 2168 * A request from crypto driver backlog is going to be processed now, 2169 * finish the completion and continue in crypt_convert(). 2170 * (Callback will be called for the second time for this request.) 2171 */ 2172 if (error == -EINPROGRESS) { 2173 complete(&ctx->restart); 2174 return; 2175 } 2176 2177 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post) 2178 error = cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq); 2179 2180 if (error == -EBADMSG) { 2181 char b[BDEVNAME_SIZE]; 2182 sector_t s = le64_to_cpu(*org_sector_of_dmreq(cc, dmreq)); 2183 2184 DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu", 2185 bio_devname(ctx->bio_in, b), s); 2186 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead", 2187 ctx->bio_in, s, 0); 2188 io->error = BLK_STS_PROTECTION; 2189 } else if (error < 0) 2190 io->error = BLK_STS_IOERR; 2191 2192 crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio); 2193 2194 if (!atomic_dec_and_test(&ctx->cc_pending)) 2195 return; 2196 2197 /* 2198 * The request is fully completed: for inline writes, let 2199 * kcryptd_crypt_write_convert() do the IO submission. 2200 */ 2201 if (bio_data_dir(io->base_bio) == READ) { 2202 kcryptd_crypt_read_done(io); 2203 return; 2204 } 2205 2206 if (kcryptd_crypt_write_inline(cc, ctx)) { 2207 complete(&ctx->restart); 2208 return; 2209 } 2210 2211 kcryptd_crypt_write_io_submit(io, 1); 2212 } 2213 2214 static void kcryptd_crypt(struct work_struct *work) 2215 { 2216 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2217 2218 if (bio_data_dir(io->base_bio) == READ) 2219 kcryptd_crypt_read_convert(io); 2220 else 2221 kcryptd_crypt_write_convert(io); 2222 } 2223 2224 static void kcryptd_crypt_tasklet(unsigned long work) 2225 { 2226 kcryptd_crypt((struct work_struct *)work); 2227 } 2228 2229 static void kcryptd_queue_crypt(struct dm_crypt_io *io) 2230 { 2231 struct crypt_config *cc = io->cc; 2232 2233 if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) || 2234 (bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) { 2235 /* 2236 * in_hardirq(): Crypto API's skcipher_walk_first() refuses to work in hard IRQ context. 2237 * irqs_disabled(): the kernel may run some IO completion from the idle thread, but 2238 * it is being executed with irqs disabled. 2239 */ 2240 if (in_hardirq() || irqs_disabled()) { 2241 tasklet_init(&io->tasklet, kcryptd_crypt_tasklet, (unsigned long)&io->work); 2242 tasklet_schedule(&io->tasklet); 2243 return; 2244 } 2245 2246 kcryptd_crypt(&io->work); 2247 return; 2248 } 2249 2250 INIT_WORK(&io->work, kcryptd_crypt); 2251 queue_work(cc->crypt_queue, &io->work); 2252 } 2253 2254 static void crypt_free_tfms_aead(struct crypt_config *cc) 2255 { 2256 if (!cc->cipher_tfm.tfms_aead) 2257 return; 2258 2259 if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2260 crypto_free_aead(cc->cipher_tfm.tfms_aead[0]); 2261 cc->cipher_tfm.tfms_aead[0] = NULL; 2262 } 2263 2264 kfree(cc->cipher_tfm.tfms_aead); 2265 cc->cipher_tfm.tfms_aead = NULL; 2266 } 2267 2268 static void crypt_free_tfms_skcipher(struct crypt_config *cc) 2269 { 2270 unsigned i; 2271 2272 if (!cc->cipher_tfm.tfms) 2273 return; 2274 2275 for (i = 0; i < cc->tfms_count; i++) 2276 if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) { 2277 crypto_free_skcipher(cc->cipher_tfm.tfms[i]); 2278 cc->cipher_tfm.tfms[i] = NULL; 2279 } 2280 2281 kfree(cc->cipher_tfm.tfms); 2282 cc->cipher_tfm.tfms = NULL; 2283 } 2284 2285 static void crypt_free_tfms(struct crypt_config *cc) 2286 { 2287 if (crypt_integrity_aead(cc)) 2288 crypt_free_tfms_aead(cc); 2289 else 2290 crypt_free_tfms_skcipher(cc); 2291 } 2292 2293 static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode) 2294 { 2295 unsigned i; 2296 int err; 2297 2298 cc->cipher_tfm.tfms = kcalloc(cc->tfms_count, 2299 sizeof(struct crypto_skcipher *), 2300 GFP_KERNEL); 2301 if (!cc->cipher_tfm.tfms) 2302 return -ENOMEM; 2303 2304 for (i = 0; i < cc->tfms_count; i++) { 2305 cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0, 2306 CRYPTO_ALG_ALLOCATES_MEMORY); 2307 if (IS_ERR(cc->cipher_tfm.tfms[i])) { 2308 err = PTR_ERR(cc->cipher_tfm.tfms[i]); 2309 crypt_free_tfms(cc); 2310 return err; 2311 } 2312 } 2313 2314 /* 2315 * dm-crypt performance can vary greatly depending on which crypto 2316 * algorithm implementation is used. Help people debug performance 2317 * problems by logging the ->cra_driver_name. 2318 */ 2319 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2320 crypto_skcipher_alg(any_tfm(cc))->base.cra_driver_name); 2321 return 0; 2322 } 2323 2324 static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode) 2325 { 2326 int err; 2327 2328 cc->cipher_tfm.tfms = kmalloc(sizeof(struct crypto_aead *), GFP_KERNEL); 2329 if (!cc->cipher_tfm.tfms) 2330 return -ENOMEM; 2331 2332 cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0, 2333 CRYPTO_ALG_ALLOCATES_MEMORY); 2334 if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2335 err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]); 2336 crypt_free_tfms(cc); 2337 return err; 2338 } 2339 2340 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2341 crypto_aead_alg(any_tfm_aead(cc))->base.cra_driver_name); 2342 return 0; 2343 } 2344 2345 static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode) 2346 { 2347 if (crypt_integrity_aead(cc)) 2348 return crypt_alloc_tfms_aead(cc, ciphermode); 2349 else 2350 return crypt_alloc_tfms_skcipher(cc, ciphermode); 2351 } 2352 2353 static unsigned crypt_subkey_size(struct crypt_config *cc) 2354 { 2355 return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count); 2356 } 2357 2358 static unsigned crypt_authenckey_size(struct crypt_config *cc) 2359 { 2360 return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param)); 2361 } 2362 2363 /* 2364 * If AEAD is composed like authenc(hmac(sha256),xts(aes)), 2365 * the key must be for some reason in special format. 2366 * This funcion converts cc->key to this special format. 2367 */ 2368 static void crypt_copy_authenckey(char *p, const void *key, 2369 unsigned enckeylen, unsigned authkeylen) 2370 { 2371 struct crypto_authenc_key_param *param; 2372 struct rtattr *rta; 2373 2374 rta = (struct rtattr *)p; 2375 param = RTA_DATA(rta); 2376 param->enckeylen = cpu_to_be32(enckeylen); 2377 rta->rta_len = RTA_LENGTH(sizeof(*param)); 2378 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; 2379 p += RTA_SPACE(sizeof(*param)); 2380 memcpy(p, key + enckeylen, authkeylen); 2381 p += authkeylen; 2382 memcpy(p, key, enckeylen); 2383 } 2384 2385 static int crypt_setkey(struct crypt_config *cc) 2386 { 2387 unsigned subkey_size; 2388 int err = 0, i, r; 2389 2390 /* Ignore extra keys (which are used for IV etc) */ 2391 subkey_size = crypt_subkey_size(cc); 2392 2393 if (crypt_integrity_hmac(cc)) { 2394 if (subkey_size < cc->key_mac_size) 2395 return -EINVAL; 2396 2397 crypt_copy_authenckey(cc->authenc_key, cc->key, 2398 subkey_size - cc->key_mac_size, 2399 cc->key_mac_size); 2400 } 2401 2402 for (i = 0; i < cc->tfms_count; i++) { 2403 if (crypt_integrity_hmac(cc)) 2404 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2405 cc->authenc_key, crypt_authenckey_size(cc)); 2406 else if (crypt_integrity_aead(cc)) 2407 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2408 cc->key + (i * subkey_size), 2409 subkey_size); 2410 else 2411 r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i], 2412 cc->key + (i * subkey_size), 2413 subkey_size); 2414 if (r) 2415 err = r; 2416 } 2417 2418 if (crypt_integrity_hmac(cc)) 2419 memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc)); 2420 2421 return err; 2422 } 2423 2424 #ifdef CONFIG_KEYS 2425 2426 static bool contains_whitespace(const char *str) 2427 { 2428 while (*str) 2429 if (isspace(*str++)) 2430 return true; 2431 return false; 2432 } 2433 2434 static int set_key_user(struct crypt_config *cc, struct key *key) 2435 { 2436 const struct user_key_payload *ukp; 2437 2438 ukp = user_key_payload_locked(key); 2439 if (!ukp) 2440 return -EKEYREVOKED; 2441 2442 if (cc->key_size != ukp->datalen) 2443 return -EINVAL; 2444 2445 memcpy(cc->key, ukp->data, cc->key_size); 2446 2447 return 0; 2448 } 2449 2450 static int set_key_encrypted(struct crypt_config *cc, struct key *key) 2451 { 2452 const struct encrypted_key_payload *ekp; 2453 2454 ekp = key->payload.data[0]; 2455 if (!ekp) 2456 return -EKEYREVOKED; 2457 2458 if (cc->key_size != ekp->decrypted_datalen) 2459 return -EINVAL; 2460 2461 memcpy(cc->key, ekp->decrypted_data, cc->key_size); 2462 2463 return 0; 2464 } 2465 2466 static int set_key_trusted(struct crypt_config *cc, struct key *key) 2467 { 2468 const struct trusted_key_payload *tkp; 2469 2470 tkp = key->payload.data[0]; 2471 if (!tkp) 2472 return -EKEYREVOKED; 2473 2474 if (cc->key_size != tkp->key_len) 2475 return -EINVAL; 2476 2477 memcpy(cc->key, tkp->key, cc->key_size); 2478 2479 return 0; 2480 } 2481 2482 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2483 { 2484 char *new_key_string, *key_desc; 2485 int ret; 2486 struct key_type *type; 2487 struct key *key; 2488 int (*set_key)(struct crypt_config *cc, struct key *key); 2489 2490 /* 2491 * Reject key_string with whitespace. dm core currently lacks code for 2492 * proper whitespace escaping in arguments on DM_TABLE_STATUS path. 2493 */ 2494 if (contains_whitespace(key_string)) { 2495 DMERR("whitespace chars not allowed in key string"); 2496 return -EINVAL; 2497 } 2498 2499 /* look for next ':' separating key_type from key_description */ 2500 key_desc = strpbrk(key_string, ":"); 2501 if (!key_desc || key_desc == key_string || !strlen(key_desc + 1)) 2502 return -EINVAL; 2503 2504 if (!strncmp(key_string, "logon:", key_desc - key_string + 1)) { 2505 type = &key_type_logon; 2506 set_key = set_key_user; 2507 } else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) { 2508 type = &key_type_user; 2509 set_key = set_key_user; 2510 } else if (IS_ENABLED(CONFIG_ENCRYPTED_KEYS) && 2511 !strncmp(key_string, "encrypted:", key_desc - key_string + 1)) { 2512 type = &key_type_encrypted; 2513 set_key = set_key_encrypted; 2514 } else if (IS_ENABLED(CONFIG_TRUSTED_KEYS) && 2515 !strncmp(key_string, "trusted:", key_desc - key_string + 1)) { 2516 type = &key_type_trusted; 2517 set_key = set_key_trusted; 2518 } else { 2519 return -EINVAL; 2520 } 2521 2522 new_key_string = kstrdup(key_string, GFP_KERNEL); 2523 if (!new_key_string) 2524 return -ENOMEM; 2525 2526 key = request_key(type, key_desc + 1, NULL); 2527 if (IS_ERR(key)) { 2528 kfree_sensitive(new_key_string); 2529 return PTR_ERR(key); 2530 } 2531 2532 down_read(&key->sem); 2533 2534 ret = set_key(cc, key); 2535 if (ret < 0) { 2536 up_read(&key->sem); 2537 key_put(key); 2538 kfree_sensitive(new_key_string); 2539 return ret; 2540 } 2541 2542 up_read(&key->sem); 2543 key_put(key); 2544 2545 /* clear the flag since following operations may invalidate previously valid key */ 2546 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2547 2548 ret = crypt_setkey(cc); 2549 2550 if (!ret) { 2551 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2552 kfree_sensitive(cc->key_string); 2553 cc->key_string = new_key_string; 2554 } else 2555 kfree_sensitive(new_key_string); 2556 2557 return ret; 2558 } 2559 2560 static int get_key_size(char **key_string) 2561 { 2562 char *colon, dummy; 2563 int ret; 2564 2565 if (*key_string[0] != ':') 2566 return strlen(*key_string) >> 1; 2567 2568 /* look for next ':' in key string */ 2569 colon = strpbrk(*key_string + 1, ":"); 2570 if (!colon) 2571 return -EINVAL; 2572 2573 if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':') 2574 return -EINVAL; 2575 2576 *key_string = colon; 2577 2578 /* remaining key string should be :<logon|user>:<key_desc> */ 2579 2580 return ret; 2581 } 2582 2583 #else 2584 2585 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2586 { 2587 return -EINVAL; 2588 } 2589 2590 static int get_key_size(char **key_string) 2591 { 2592 return (*key_string[0] == ':') ? -EINVAL : strlen(*key_string) >> 1; 2593 } 2594 2595 #endif /* CONFIG_KEYS */ 2596 2597 static int crypt_set_key(struct crypt_config *cc, char *key) 2598 { 2599 int r = -EINVAL; 2600 int key_string_len = strlen(key); 2601 2602 /* Hyphen (which gives a key_size of zero) means there is no key. */ 2603 if (!cc->key_size && strcmp(key, "-")) 2604 goto out; 2605 2606 /* ':' means the key is in kernel keyring, short-circuit normal key processing */ 2607 if (key[0] == ':') { 2608 r = crypt_set_keyring_key(cc, key + 1); 2609 goto out; 2610 } 2611 2612 /* clear the flag since following operations may invalidate previously valid key */ 2613 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2614 2615 /* wipe references to any kernel keyring key */ 2616 kfree_sensitive(cc->key_string); 2617 cc->key_string = NULL; 2618 2619 /* Decode key from its hex representation. */ 2620 if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0) 2621 goto out; 2622 2623 r = crypt_setkey(cc); 2624 if (!r) 2625 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2626 2627 out: 2628 /* Hex key string not needed after here, so wipe it. */ 2629 memset(key, '0', key_string_len); 2630 2631 return r; 2632 } 2633 2634 static int crypt_wipe_key(struct crypt_config *cc) 2635 { 2636 int r; 2637 2638 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2639 get_random_bytes(&cc->key, cc->key_size); 2640 2641 /* Wipe IV private keys */ 2642 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) { 2643 r = cc->iv_gen_ops->wipe(cc); 2644 if (r) 2645 return r; 2646 } 2647 2648 kfree_sensitive(cc->key_string); 2649 cc->key_string = NULL; 2650 r = crypt_setkey(cc); 2651 memset(&cc->key, 0, cc->key_size * sizeof(u8)); 2652 2653 return r; 2654 } 2655 2656 static void crypt_calculate_pages_per_client(void) 2657 { 2658 unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100; 2659 2660 if (!dm_crypt_clients_n) 2661 return; 2662 2663 pages /= dm_crypt_clients_n; 2664 if (pages < DM_CRYPT_MIN_PAGES_PER_CLIENT) 2665 pages = DM_CRYPT_MIN_PAGES_PER_CLIENT; 2666 dm_crypt_pages_per_client = pages; 2667 } 2668 2669 static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data) 2670 { 2671 struct crypt_config *cc = pool_data; 2672 struct page *page; 2673 2674 /* 2675 * Note, percpu_counter_read_positive() may over (and under) estimate 2676 * the current usage by at most (batch - 1) * num_online_cpus() pages, 2677 * but avoids potential spinlock contention of an exact result. 2678 */ 2679 if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) >= dm_crypt_pages_per_client) && 2680 likely(gfp_mask & __GFP_NORETRY)) 2681 return NULL; 2682 2683 page = alloc_page(gfp_mask); 2684 if (likely(page != NULL)) 2685 percpu_counter_add(&cc->n_allocated_pages, 1); 2686 2687 return page; 2688 } 2689 2690 static void crypt_page_free(void *page, void *pool_data) 2691 { 2692 struct crypt_config *cc = pool_data; 2693 2694 __free_page(page); 2695 percpu_counter_sub(&cc->n_allocated_pages, 1); 2696 } 2697 2698 static void crypt_dtr(struct dm_target *ti) 2699 { 2700 struct crypt_config *cc = ti->private; 2701 2702 ti->private = NULL; 2703 2704 if (!cc) 2705 return; 2706 2707 if (cc->write_thread) 2708 kthread_stop(cc->write_thread); 2709 2710 if (cc->io_queue) 2711 destroy_workqueue(cc->io_queue); 2712 if (cc->crypt_queue) 2713 destroy_workqueue(cc->crypt_queue); 2714 2715 crypt_free_tfms(cc); 2716 2717 bioset_exit(&cc->bs); 2718 2719 mempool_exit(&cc->page_pool); 2720 mempool_exit(&cc->req_pool); 2721 mempool_exit(&cc->tag_pool); 2722 2723 WARN_ON(percpu_counter_sum(&cc->n_allocated_pages) != 0); 2724 percpu_counter_destroy(&cc->n_allocated_pages); 2725 2726 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) 2727 cc->iv_gen_ops->dtr(cc); 2728 2729 if (cc->dev) 2730 dm_put_device(ti, cc->dev); 2731 2732 kfree_sensitive(cc->cipher_string); 2733 kfree_sensitive(cc->key_string); 2734 kfree_sensitive(cc->cipher_auth); 2735 kfree_sensitive(cc->authenc_key); 2736 2737 mutex_destroy(&cc->bio_alloc_lock); 2738 2739 /* Must zero key material before freeing */ 2740 kfree_sensitive(cc); 2741 2742 spin_lock(&dm_crypt_clients_lock); 2743 WARN_ON(!dm_crypt_clients_n); 2744 dm_crypt_clients_n--; 2745 crypt_calculate_pages_per_client(); 2746 spin_unlock(&dm_crypt_clients_lock); 2747 2748 dm_audit_log_dtr(DM_MSG_PREFIX, ti, 1); 2749 } 2750 2751 static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode) 2752 { 2753 struct crypt_config *cc = ti->private; 2754 2755 if (crypt_integrity_aead(cc)) 2756 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2757 else 2758 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2759 2760 if (cc->iv_size) 2761 /* at least a 64 bit sector number should fit in our buffer */ 2762 cc->iv_size = max(cc->iv_size, 2763 (unsigned int)(sizeof(u64) / sizeof(u8))); 2764 else if (ivmode) { 2765 DMWARN("Selected cipher does not support IVs"); 2766 ivmode = NULL; 2767 } 2768 2769 /* Choose ivmode, see comments at iv code. */ 2770 if (ivmode == NULL) 2771 cc->iv_gen_ops = NULL; 2772 else if (strcmp(ivmode, "plain") == 0) 2773 cc->iv_gen_ops = &crypt_iv_plain_ops; 2774 else if (strcmp(ivmode, "plain64") == 0) 2775 cc->iv_gen_ops = &crypt_iv_plain64_ops; 2776 else if (strcmp(ivmode, "plain64be") == 0) 2777 cc->iv_gen_ops = &crypt_iv_plain64be_ops; 2778 else if (strcmp(ivmode, "essiv") == 0) 2779 cc->iv_gen_ops = &crypt_iv_essiv_ops; 2780 else if (strcmp(ivmode, "benbi") == 0) 2781 cc->iv_gen_ops = &crypt_iv_benbi_ops; 2782 else if (strcmp(ivmode, "null") == 0) 2783 cc->iv_gen_ops = &crypt_iv_null_ops; 2784 else if (strcmp(ivmode, "eboiv") == 0) 2785 cc->iv_gen_ops = &crypt_iv_eboiv_ops; 2786 else if (strcmp(ivmode, "elephant") == 0) { 2787 cc->iv_gen_ops = &crypt_iv_elephant_ops; 2788 cc->key_parts = 2; 2789 cc->key_extra_size = cc->key_size / 2; 2790 if (cc->key_extra_size > ELEPHANT_MAX_KEY_SIZE) 2791 return -EINVAL; 2792 set_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags); 2793 } else if (strcmp(ivmode, "lmk") == 0) { 2794 cc->iv_gen_ops = &crypt_iv_lmk_ops; 2795 /* 2796 * Version 2 and 3 is recognised according 2797 * to length of provided multi-key string. 2798 * If present (version 3), last key is used as IV seed. 2799 * All keys (including IV seed) are always the same size. 2800 */ 2801 if (cc->key_size % cc->key_parts) { 2802 cc->key_parts++; 2803 cc->key_extra_size = cc->key_size / cc->key_parts; 2804 } 2805 } else if (strcmp(ivmode, "tcw") == 0) { 2806 cc->iv_gen_ops = &crypt_iv_tcw_ops; 2807 cc->key_parts += 2; /* IV + whitening */ 2808 cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE; 2809 } else if (strcmp(ivmode, "random") == 0) { 2810 cc->iv_gen_ops = &crypt_iv_random_ops; 2811 /* Need storage space in integrity fields. */ 2812 cc->integrity_iv_size = cc->iv_size; 2813 } else { 2814 ti->error = "Invalid IV mode"; 2815 return -EINVAL; 2816 } 2817 2818 return 0; 2819 } 2820 2821 /* 2822 * Workaround to parse HMAC algorithm from AEAD crypto API spec. 2823 * The HMAC is needed to calculate tag size (HMAC digest size). 2824 * This should be probably done by crypto-api calls (once available...) 2825 */ 2826 static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api) 2827 { 2828 char *start, *end, *mac_alg = NULL; 2829 struct crypto_ahash *mac; 2830 2831 if (!strstarts(cipher_api, "authenc(")) 2832 return 0; 2833 2834 start = strchr(cipher_api, '('); 2835 end = strchr(cipher_api, ','); 2836 if (!start || !end || ++start > end) 2837 return -EINVAL; 2838 2839 mac_alg = kzalloc(end - start + 1, GFP_KERNEL); 2840 if (!mac_alg) 2841 return -ENOMEM; 2842 strncpy(mac_alg, start, end - start); 2843 2844 mac = crypto_alloc_ahash(mac_alg, 0, CRYPTO_ALG_ALLOCATES_MEMORY); 2845 kfree(mac_alg); 2846 2847 if (IS_ERR(mac)) 2848 return PTR_ERR(mac); 2849 2850 cc->key_mac_size = crypto_ahash_digestsize(mac); 2851 crypto_free_ahash(mac); 2852 2853 cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL); 2854 if (!cc->authenc_key) 2855 return -ENOMEM; 2856 2857 return 0; 2858 } 2859 2860 static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key, 2861 char **ivmode, char **ivopts) 2862 { 2863 struct crypt_config *cc = ti->private; 2864 char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME]; 2865 int ret = -EINVAL; 2866 2867 cc->tfms_count = 1; 2868 2869 /* 2870 * New format (capi: prefix) 2871 * capi:cipher_api_spec-iv:ivopts 2872 */ 2873 tmp = &cipher_in[strlen("capi:")]; 2874 2875 /* Separate IV options if present, it can contain another '-' in hash name */ 2876 *ivopts = strrchr(tmp, ':'); 2877 if (*ivopts) { 2878 **ivopts = '\0'; 2879 (*ivopts)++; 2880 } 2881 /* Parse IV mode */ 2882 *ivmode = strrchr(tmp, '-'); 2883 if (*ivmode) { 2884 **ivmode = '\0'; 2885 (*ivmode)++; 2886 } 2887 /* The rest is crypto API spec */ 2888 cipher_api = tmp; 2889 2890 /* Alloc AEAD, can be used only in new format. */ 2891 if (crypt_integrity_aead(cc)) { 2892 ret = crypt_ctr_auth_cipher(cc, cipher_api); 2893 if (ret < 0) { 2894 ti->error = "Invalid AEAD cipher spec"; 2895 return -ENOMEM; 2896 } 2897 } 2898 2899 if (*ivmode && !strcmp(*ivmode, "lmk")) 2900 cc->tfms_count = 64; 2901 2902 if (*ivmode && !strcmp(*ivmode, "essiv")) { 2903 if (!*ivopts) { 2904 ti->error = "Digest algorithm missing for ESSIV mode"; 2905 return -EINVAL; 2906 } 2907 ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)", 2908 cipher_api, *ivopts); 2909 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 2910 ti->error = "Cannot allocate cipher string"; 2911 return -ENOMEM; 2912 } 2913 cipher_api = buf; 2914 } 2915 2916 cc->key_parts = cc->tfms_count; 2917 2918 /* Allocate cipher */ 2919 ret = crypt_alloc_tfms(cc, cipher_api); 2920 if (ret < 0) { 2921 ti->error = "Error allocating crypto tfm"; 2922 return ret; 2923 } 2924 2925 if (crypt_integrity_aead(cc)) 2926 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2927 else 2928 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2929 2930 return 0; 2931 } 2932 2933 static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key, 2934 char **ivmode, char **ivopts) 2935 { 2936 struct crypt_config *cc = ti->private; 2937 char *tmp, *cipher, *chainmode, *keycount; 2938 char *cipher_api = NULL; 2939 int ret = -EINVAL; 2940 char dummy; 2941 2942 if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) { 2943 ti->error = "Bad cipher specification"; 2944 return -EINVAL; 2945 } 2946 2947 /* 2948 * Legacy dm-crypt cipher specification 2949 * cipher[:keycount]-mode-iv:ivopts 2950 */ 2951 tmp = cipher_in; 2952 keycount = strsep(&tmp, "-"); 2953 cipher = strsep(&keycount, ":"); 2954 2955 if (!keycount) 2956 cc->tfms_count = 1; 2957 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 || 2958 !is_power_of_2(cc->tfms_count)) { 2959 ti->error = "Bad cipher key count specification"; 2960 return -EINVAL; 2961 } 2962 cc->key_parts = cc->tfms_count; 2963 2964 chainmode = strsep(&tmp, "-"); 2965 *ivmode = strsep(&tmp, ":"); 2966 *ivopts = tmp; 2967 2968 /* 2969 * For compatibility with the original dm-crypt mapping format, if 2970 * only the cipher name is supplied, use cbc-plain. 2971 */ 2972 if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) { 2973 chainmode = "cbc"; 2974 *ivmode = "plain"; 2975 } 2976 2977 if (strcmp(chainmode, "ecb") && !*ivmode) { 2978 ti->error = "IV mechanism required"; 2979 return -EINVAL; 2980 } 2981 2982 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL); 2983 if (!cipher_api) 2984 goto bad_mem; 2985 2986 if (*ivmode && !strcmp(*ivmode, "essiv")) { 2987 if (!*ivopts) { 2988 ti->error = "Digest algorithm missing for ESSIV mode"; 2989 kfree(cipher_api); 2990 return -EINVAL; 2991 } 2992 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 2993 "essiv(%s(%s),%s)", chainmode, cipher, *ivopts); 2994 } else { 2995 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 2996 "%s(%s)", chainmode, cipher); 2997 } 2998 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 2999 kfree(cipher_api); 3000 goto bad_mem; 3001 } 3002 3003 /* Allocate cipher */ 3004 ret = crypt_alloc_tfms(cc, cipher_api); 3005 if (ret < 0) { 3006 ti->error = "Error allocating crypto tfm"; 3007 kfree(cipher_api); 3008 return ret; 3009 } 3010 kfree(cipher_api); 3011 3012 return 0; 3013 bad_mem: 3014 ti->error = "Cannot allocate cipher strings"; 3015 return -ENOMEM; 3016 } 3017 3018 static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key) 3019 { 3020 struct crypt_config *cc = ti->private; 3021 char *ivmode = NULL, *ivopts = NULL; 3022 int ret; 3023 3024 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL); 3025 if (!cc->cipher_string) { 3026 ti->error = "Cannot allocate cipher strings"; 3027 return -ENOMEM; 3028 } 3029 3030 if (strstarts(cipher_in, "capi:")) 3031 ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts); 3032 else 3033 ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts); 3034 if (ret) 3035 return ret; 3036 3037 /* Initialize IV */ 3038 ret = crypt_ctr_ivmode(ti, ivmode); 3039 if (ret < 0) 3040 return ret; 3041 3042 /* Initialize and set key */ 3043 ret = crypt_set_key(cc, key); 3044 if (ret < 0) { 3045 ti->error = "Error decoding and setting key"; 3046 return ret; 3047 } 3048 3049 /* Allocate IV */ 3050 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) { 3051 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts); 3052 if (ret < 0) { 3053 ti->error = "Error creating IV"; 3054 return ret; 3055 } 3056 } 3057 3058 /* Initialize IV (set keys for ESSIV etc) */ 3059 if (cc->iv_gen_ops && cc->iv_gen_ops->init) { 3060 ret = cc->iv_gen_ops->init(cc); 3061 if (ret < 0) { 3062 ti->error = "Error initialising IV"; 3063 return ret; 3064 } 3065 } 3066 3067 /* wipe the kernel key payload copy */ 3068 if (cc->key_string) 3069 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3070 3071 return ret; 3072 } 3073 3074 static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv) 3075 { 3076 struct crypt_config *cc = ti->private; 3077 struct dm_arg_set as; 3078 static const struct dm_arg _args[] = { 3079 {0, 8, "Invalid number of feature args"}, 3080 }; 3081 unsigned int opt_params, val; 3082 const char *opt_string, *sval; 3083 char dummy; 3084 int ret; 3085 3086 /* Optional parameters */ 3087 as.argc = argc; 3088 as.argv = argv; 3089 3090 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error); 3091 if (ret) 3092 return ret; 3093 3094 while (opt_params--) { 3095 opt_string = dm_shift_arg(&as); 3096 if (!opt_string) { 3097 ti->error = "Not enough feature arguments"; 3098 return -EINVAL; 3099 } 3100 3101 if (!strcasecmp(opt_string, "allow_discards")) 3102 ti->num_discard_bios = 1; 3103 3104 else if (!strcasecmp(opt_string, "same_cpu_crypt")) 3105 set_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3106 3107 else if (!strcasecmp(opt_string, "submit_from_crypt_cpus")) 3108 set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3109 else if (!strcasecmp(opt_string, "no_read_workqueue")) 3110 set_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3111 else if (!strcasecmp(opt_string, "no_write_workqueue")) 3112 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3113 else if (sscanf(opt_string, "integrity:%u:", &val) == 1) { 3114 if (val == 0 || val > MAX_TAG_SIZE) { 3115 ti->error = "Invalid integrity arguments"; 3116 return -EINVAL; 3117 } 3118 cc->on_disk_tag_size = val; 3119 sval = strchr(opt_string + strlen("integrity:"), ':') + 1; 3120 if (!strcasecmp(sval, "aead")) { 3121 set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 3122 } else if (strcasecmp(sval, "none")) { 3123 ti->error = "Unknown integrity profile"; 3124 return -EINVAL; 3125 } 3126 3127 cc->cipher_auth = kstrdup(sval, GFP_KERNEL); 3128 if (!cc->cipher_auth) 3129 return -ENOMEM; 3130 } else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) { 3131 if (cc->sector_size < (1 << SECTOR_SHIFT) || 3132 cc->sector_size > 4096 || 3133 (cc->sector_size & (cc->sector_size - 1))) { 3134 ti->error = "Invalid feature value for sector_size"; 3135 return -EINVAL; 3136 } 3137 if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) { 3138 ti->error = "Device size is not multiple of sector_size feature"; 3139 return -EINVAL; 3140 } 3141 cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT; 3142 } else if (!strcasecmp(opt_string, "iv_large_sectors")) 3143 set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3144 else { 3145 ti->error = "Invalid feature arguments"; 3146 return -EINVAL; 3147 } 3148 } 3149 3150 return 0; 3151 } 3152 3153 #ifdef CONFIG_BLK_DEV_ZONED 3154 static int crypt_report_zones(struct dm_target *ti, 3155 struct dm_report_zones_args *args, unsigned int nr_zones) 3156 { 3157 struct crypt_config *cc = ti->private; 3158 3159 return dm_report_zones(cc->dev->bdev, cc->start, 3160 cc->start + dm_target_offset(ti, args->next_sector), 3161 args, nr_zones); 3162 } 3163 #else 3164 #define crypt_report_zones NULL 3165 #endif 3166 3167 /* 3168 * Construct an encryption mapping: 3169 * <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start> 3170 */ 3171 static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) 3172 { 3173 struct crypt_config *cc; 3174 const char *devname = dm_table_device_name(ti->table); 3175 int key_size; 3176 unsigned int align_mask; 3177 unsigned long long tmpll; 3178 int ret; 3179 size_t iv_size_padding, additional_req_size; 3180 char dummy; 3181 3182 if (argc < 5) { 3183 ti->error = "Not enough arguments"; 3184 return -EINVAL; 3185 } 3186 3187 key_size = get_key_size(&argv[1]); 3188 if (key_size < 0) { 3189 ti->error = "Cannot parse key size"; 3190 return -EINVAL; 3191 } 3192 3193 cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL); 3194 if (!cc) { 3195 ti->error = "Cannot allocate encryption context"; 3196 return -ENOMEM; 3197 } 3198 cc->key_size = key_size; 3199 cc->sector_size = (1 << SECTOR_SHIFT); 3200 cc->sector_shift = 0; 3201 3202 ti->private = cc; 3203 3204 spin_lock(&dm_crypt_clients_lock); 3205 dm_crypt_clients_n++; 3206 crypt_calculate_pages_per_client(); 3207 spin_unlock(&dm_crypt_clients_lock); 3208 3209 ret = percpu_counter_init(&cc->n_allocated_pages, 0, GFP_KERNEL); 3210 if (ret < 0) 3211 goto bad; 3212 3213 /* Optional parameters need to be read before cipher constructor */ 3214 if (argc > 5) { 3215 ret = crypt_ctr_optional(ti, argc - 5, &argv[5]); 3216 if (ret) 3217 goto bad; 3218 } 3219 3220 ret = crypt_ctr_cipher(ti, argv[0], argv[1]); 3221 if (ret < 0) 3222 goto bad; 3223 3224 if (crypt_integrity_aead(cc)) { 3225 cc->dmreq_start = sizeof(struct aead_request); 3226 cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc)); 3227 align_mask = crypto_aead_alignmask(any_tfm_aead(cc)); 3228 } else { 3229 cc->dmreq_start = sizeof(struct skcipher_request); 3230 cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc)); 3231 align_mask = crypto_skcipher_alignmask(any_tfm(cc)); 3232 } 3233 cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request)); 3234 3235 if (align_mask < CRYPTO_MINALIGN) { 3236 /* Allocate the padding exactly */ 3237 iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request)) 3238 & align_mask; 3239 } else { 3240 /* 3241 * If the cipher requires greater alignment than kmalloc 3242 * alignment, we don't know the exact position of the 3243 * initialization vector. We must assume worst case. 3244 */ 3245 iv_size_padding = align_mask; 3246 } 3247 3248 /* ...| IV + padding | original IV | original sec. number | bio tag offset | */ 3249 additional_req_size = sizeof(struct dm_crypt_request) + 3250 iv_size_padding + cc->iv_size + 3251 cc->iv_size + 3252 sizeof(uint64_t) + 3253 sizeof(unsigned int); 3254 3255 ret = mempool_init_kmalloc_pool(&cc->req_pool, MIN_IOS, cc->dmreq_start + additional_req_size); 3256 if (ret) { 3257 ti->error = "Cannot allocate crypt request mempool"; 3258 goto bad; 3259 } 3260 3261 cc->per_bio_data_size = ti->per_io_data_size = 3262 ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size, 3263 ARCH_KMALLOC_MINALIGN); 3264 3265 ret = mempool_init(&cc->page_pool, BIO_MAX_VECS, crypt_page_alloc, crypt_page_free, cc); 3266 if (ret) { 3267 ti->error = "Cannot allocate page mempool"; 3268 goto bad; 3269 } 3270 3271 ret = bioset_init(&cc->bs, MIN_IOS, 0, BIOSET_NEED_BVECS); 3272 if (ret) { 3273 ti->error = "Cannot allocate crypt bioset"; 3274 goto bad; 3275 } 3276 3277 mutex_init(&cc->bio_alloc_lock); 3278 3279 ret = -EINVAL; 3280 if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) || 3281 (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) { 3282 ti->error = "Invalid iv_offset sector"; 3283 goto bad; 3284 } 3285 cc->iv_offset = tmpll; 3286 3287 ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev); 3288 if (ret) { 3289 ti->error = "Device lookup failed"; 3290 goto bad; 3291 } 3292 3293 ret = -EINVAL; 3294 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) { 3295 ti->error = "Invalid device sector"; 3296 goto bad; 3297 } 3298 cc->start = tmpll; 3299 3300 if (bdev_is_zoned(cc->dev->bdev)) { 3301 /* 3302 * For zoned block devices, we need to preserve the issuer write 3303 * ordering. To do so, disable write workqueues and force inline 3304 * encryption completion. 3305 */ 3306 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3307 set_bit(DM_CRYPT_WRITE_INLINE, &cc->flags); 3308 3309 /* 3310 * All zone append writes to a zone of a zoned block device will 3311 * have the same BIO sector, the start of the zone. When the 3312 * cypher IV mode uses sector values, all data targeting a 3313 * zone will be encrypted using the first sector numbers of the 3314 * zone. This will not result in write errors but will 3315 * cause most reads to fail as reads will use the sector values 3316 * for the actual data locations, resulting in IV mismatch. 3317 * To avoid this problem, ask DM core to emulate zone append 3318 * operations with regular writes. 3319 */ 3320 DMDEBUG("Zone append operations will be emulated"); 3321 ti->emulate_zone_append = true; 3322 } 3323 3324 if (crypt_integrity_aead(cc) || cc->integrity_iv_size) { 3325 ret = crypt_integrity_ctr(cc, ti); 3326 if (ret) 3327 goto bad; 3328 3329 cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->on_disk_tag_size; 3330 if (!cc->tag_pool_max_sectors) 3331 cc->tag_pool_max_sectors = 1; 3332 3333 ret = mempool_init_kmalloc_pool(&cc->tag_pool, MIN_IOS, 3334 cc->tag_pool_max_sectors * cc->on_disk_tag_size); 3335 if (ret) { 3336 ti->error = "Cannot allocate integrity tags mempool"; 3337 goto bad; 3338 } 3339 3340 cc->tag_pool_max_sectors <<= cc->sector_shift; 3341 } 3342 3343 ret = -ENOMEM; 3344 cc->io_queue = alloc_workqueue("kcryptd_io/%s", WQ_MEM_RECLAIM, 1, devname); 3345 if (!cc->io_queue) { 3346 ti->error = "Couldn't create kcryptd io queue"; 3347 goto bad; 3348 } 3349 3350 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3351 cc->crypt_queue = alloc_workqueue("kcryptd/%s", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 3352 1, devname); 3353 else 3354 cc->crypt_queue = alloc_workqueue("kcryptd/%s", 3355 WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND, 3356 num_online_cpus(), devname); 3357 if (!cc->crypt_queue) { 3358 ti->error = "Couldn't create kcryptd queue"; 3359 goto bad; 3360 } 3361 3362 spin_lock_init(&cc->write_thread_lock); 3363 cc->write_tree = RB_ROOT; 3364 3365 cc->write_thread = kthread_run(dmcrypt_write, cc, "dmcrypt_write/%s", devname); 3366 if (IS_ERR(cc->write_thread)) { 3367 ret = PTR_ERR(cc->write_thread); 3368 cc->write_thread = NULL; 3369 ti->error = "Couldn't spawn write thread"; 3370 goto bad; 3371 } 3372 3373 ti->num_flush_bios = 1; 3374 ti->limit_swap_bios = true; 3375 3376 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 1); 3377 return 0; 3378 3379 bad: 3380 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 0); 3381 crypt_dtr(ti); 3382 return ret; 3383 } 3384 3385 static int crypt_map(struct dm_target *ti, struct bio *bio) 3386 { 3387 struct dm_crypt_io *io; 3388 struct crypt_config *cc = ti->private; 3389 3390 /* 3391 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues. 3392 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight 3393 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters 3394 */ 3395 if (unlikely(bio->bi_opf & REQ_PREFLUSH || 3396 bio_op(bio) == REQ_OP_DISCARD)) { 3397 bio_set_dev(bio, cc->dev->bdev); 3398 if (bio_sectors(bio)) 3399 bio->bi_iter.bi_sector = cc->start + 3400 dm_target_offset(ti, bio->bi_iter.bi_sector); 3401 return DM_MAPIO_REMAPPED; 3402 } 3403 3404 /* 3405 * Check if bio is too large, split as needed. 3406 */ 3407 if (unlikely(bio->bi_iter.bi_size > (BIO_MAX_VECS << PAGE_SHIFT)) && 3408 (bio_data_dir(bio) == WRITE || cc->on_disk_tag_size)) 3409 dm_accept_partial_bio(bio, ((BIO_MAX_VECS << PAGE_SHIFT) >> SECTOR_SHIFT)); 3410 3411 /* 3412 * Ensure that bio is a multiple of internal sector encryption size 3413 * and is aligned to this size as defined in IO hints. 3414 */ 3415 if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0)) 3416 return DM_MAPIO_KILL; 3417 3418 if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1))) 3419 return DM_MAPIO_KILL; 3420 3421 io = dm_per_bio_data(bio, cc->per_bio_data_size); 3422 crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector)); 3423 3424 if (cc->on_disk_tag_size) { 3425 unsigned tag_len = cc->on_disk_tag_size * (bio_sectors(bio) >> cc->sector_shift); 3426 3427 if (unlikely(tag_len > KMALLOC_MAX_SIZE) || 3428 unlikely(!(io->integrity_metadata = kmalloc(tag_len, 3429 GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN)))) { 3430 if (bio_sectors(bio) > cc->tag_pool_max_sectors) 3431 dm_accept_partial_bio(bio, cc->tag_pool_max_sectors); 3432 io->integrity_metadata = mempool_alloc(&cc->tag_pool, GFP_NOIO); 3433 io->integrity_metadata_from_pool = true; 3434 } 3435 } 3436 3437 if (crypt_integrity_aead(cc)) 3438 io->ctx.r.req_aead = (struct aead_request *)(io + 1); 3439 else 3440 io->ctx.r.req = (struct skcipher_request *)(io + 1); 3441 3442 if (bio_data_dir(io->base_bio) == READ) { 3443 if (kcryptd_io_read(io, GFP_NOWAIT)) 3444 kcryptd_queue_read(io); 3445 } else 3446 kcryptd_queue_crypt(io); 3447 3448 return DM_MAPIO_SUBMITTED; 3449 } 3450 3451 static void crypt_status(struct dm_target *ti, status_type_t type, 3452 unsigned status_flags, char *result, unsigned maxlen) 3453 { 3454 struct crypt_config *cc = ti->private; 3455 unsigned i, sz = 0; 3456 int num_feature_args = 0; 3457 3458 switch (type) { 3459 case STATUSTYPE_INFO: 3460 result[0] = '\0'; 3461 break; 3462 3463 case STATUSTYPE_TABLE: 3464 DMEMIT("%s ", cc->cipher_string); 3465 3466 if (cc->key_size > 0) { 3467 if (cc->key_string) 3468 DMEMIT(":%u:%s", cc->key_size, cc->key_string); 3469 else 3470 for (i = 0; i < cc->key_size; i++) 3471 DMEMIT("%02x", cc->key[i]); 3472 } else 3473 DMEMIT("-"); 3474 3475 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, 3476 cc->dev->name, (unsigned long long)cc->start); 3477 3478 num_feature_args += !!ti->num_discard_bios; 3479 num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3480 num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3481 num_feature_args += test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3482 num_feature_args += test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3483 num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT); 3484 num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3485 if (cc->on_disk_tag_size) 3486 num_feature_args++; 3487 if (num_feature_args) { 3488 DMEMIT(" %d", num_feature_args); 3489 if (ti->num_discard_bios) 3490 DMEMIT(" allow_discards"); 3491 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3492 DMEMIT(" same_cpu_crypt"); 3493 if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) 3494 DMEMIT(" submit_from_crypt_cpus"); 3495 if (test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) 3496 DMEMIT(" no_read_workqueue"); 3497 if (test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) 3498 DMEMIT(" no_write_workqueue"); 3499 if (cc->on_disk_tag_size) 3500 DMEMIT(" integrity:%u:%s", cc->on_disk_tag_size, cc->cipher_auth); 3501 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3502 DMEMIT(" sector_size:%d", cc->sector_size); 3503 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 3504 DMEMIT(" iv_large_sectors"); 3505 } 3506 break; 3507 3508 case STATUSTYPE_IMA: 3509 DMEMIT_TARGET_NAME_VERSION(ti->type); 3510 DMEMIT(",allow_discards=%c", ti->num_discard_bios ? 'y' : 'n'); 3511 DMEMIT(",same_cpu_crypt=%c", test_bit(DM_CRYPT_SAME_CPU, &cc->flags) ? 'y' : 'n'); 3512 DMEMIT(",submit_from_crypt_cpus=%c", test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags) ? 3513 'y' : 'n'); 3514 DMEMIT(",no_read_workqueue=%c", test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags) ? 3515 'y' : 'n'); 3516 DMEMIT(",no_write_workqueue=%c", test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags) ? 3517 'y' : 'n'); 3518 DMEMIT(",iv_large_sectors=%c", test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags) ? 3519 'y' : 'n'); 3520 3521 if (cc->on_disk_tag_size) 3522 DMEMIT(",integrity_tag_size=%u,cipher_auth=%s", 3523 cc->on_disk_tag_size, cc->cipher_auth); 3524 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3525 DMEMIT(",sector_size=%d", cc->sector_size); 3526 if (cc->cipher_string) 3527 DMEMIT(",cipher_string=%s", cc->cipher_string); 3528 3529 DMEMIT(",key_size=%u", cc->key_size); 3530 DMEMIT(",key_parts=%u", cc->key_parts); 3531 DMEMIT(",key_extra_size=%u", cc->key_extra_size); 3532 DMEMIT(",key_mac_size=%u", cc->key_mac_size); 3533 DMEMIT(";"); 3534 break; 3535 } 3536 } 3537 3538 static void crypt_postsuspend(struct dm_target *ti) 3539 { 3540 struct crypt_config *cc = ti->private; 3541 3542 set_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3543 } 3544 3545 static int crypt_preresume(struct dm_target *ti) 3546 { 3547 struct crypt_config *cc = ti->private; 3548 3549 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { 3550 DMERR("aborting resume - crypt key is not set."); 3551 return -EAGAIN; 3552 } 3553 3554 return 0; 3555 } 3556 3557 static void crypt_resume(struct dm_target *ti) 3558 { 3559 struct crypt_config *cc = ti->private; 3560 3561 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3562 } 3563 3564 /* Message interface 3565 * key set <key> 3566 * key wipe 3567 */ 3568 static int crypt_message(struct dm_target *ti, unsigned argc, char **argv, 3569 char *result, unsigned maxlen) 3570 { 3571 struct crypt_config *cc = ti->private; 3572 int key_size, ret = -EINVAL; 3573 3574 if (argc < 2) 3575 goto error; 3576 3577 if (!strcasecmp(argv[0], "key")) { 3578 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { 3579 DMWARN("not suspended during key manipulation."); 3580 return -EINVAL; 3581 } 3582 if (argc == 3 && !strcasecmp(argv[1], "set")) { 3583 /* The key size may not be changed. */ 3584 key_size = get_key_size(&argv[2]); 3585 if (key_size < 0 || cc->key_size != key_size) { 3586 memset(argv[2], '0', strlen(argv[2])); 3587 return -EINVAL; 3588 } 3589 3590 ret = crypt_set_key(cc, argv[2]); 3591 if (ret) 3592 return ret; 3593 if (cc->iv_gen_ops && cc->iv_gen_ops->init) 3594 ret = cc->iv_gen_ops->init(cc); 3595 /* wipe the kernel key payload copy */ 3596 if (cc->key_string) 3597 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3598 return ret; 3599 } 3600 if (argc == 2 && !strcasecmp(argv[1], "wipe")) 3601 return crypt_wipe_key(cc); 3602 } 3603 3604 error: 3605 DMWARN("unrecognised message received."); 3606 return -EINVAL; 3607 } 3608 3609 static int crypt_iterate_devices(struct dm_target *ti, 3610 iterate_devices_callout_fn fn, void *data) 3611 { 3612 struct crypt_config *cc = ti->private; 3613 3614 return fn(ti, cc->dev, cc->start, ti->len, data); 3615 } 3616 3617 static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits) 3618 { 3619 struct crypt_config *cc = ti->private; 3620 3621 /* 3622 * Unfortunate constraint that is required to avoid the potential 3623 * for exceeding underlying device's max_segments limits -- due to 3624 * crypt_alloc_buffer() possibly allocating pages for the encryption 3625 * bio that are not as physically contiguous as the original bio. 3626 */ 3627 limits->max_segment_size = PAGE_SIZE; 3628 3629 limits->logical_block_size = 3630 max_t(unsigned, limits->logical_block_size, cc->sector_size); 3631 limits->physical_block_size = 3632 max_t(unsigned, limits->physical_block_size, cc->sector_size); 3633 limits->io_min = max_t(unsigned, limits->io_min, cc->sector_size); 3634 } 3635 3636 static struct target_type crypt_target = { 3637 .name = "crypt", 3638 .version = {1, 23, 0}, 3639 .module = THIS_MODULE, 3640 .ctr = crypt_ctr, 3641 .dtr = crypt_dtr, 3642 .features = DM_TARGET_ZONED_HM, 3643 .report_zones = crypt_report_zones, 3644 .map = crypt_map, 3645 .status = crypt_status, 3646 .postsuspend = crypt_postsuspend, 3647 .preresume = crypt_preresume, 3648 .resume = crypt_resume, 3649 .message = crypt_message, 3650 .iterate_devices = crypt_iterate_devices, 3651 .io_hints = crypt_io_hints, 3652 }; 3653 3654 static int __init dm_crypt_init(void) 3655 { 3656 int r; 3657 3658 r = dm_register_target(&crypt_target); 3659 if (r < 0) 3660 DMERR("register failed %d", r); 3661 3662 return r; 3663 } 3664 3665 static void __exit dm_crypt_exit(void) 3666 { 3667 dm_unregister_target(&crypt_target); 3668 } 3669 3670 module_init(dm_crypt_init); 3671 module_exit(dm_crypt_exit); 3672 3673 MODULE_AUTHOR("Jana Saout <jana@saout.de>"); 3674 MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); 3675 MODULE_LICENSE("GPL"); 3676