1/* 2 * Copyright (C) 2003 Jana Saout <jana@saout.de> 3 * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org> 4 * Copyright (C) 2006-2020 Red Hat, Inc. All rights reserved. 5 * Copyright (C) 2013-2020 Milan Broz <gmazyland@gmail.com> 6 * 7 * This file is released under the GPL. 8 */ 9 10#include <linux/completion.h> 11#include <linux/err.h> 12#include <linux/module.h> 13#include <linux/init.h> 14#include <linux/kernel.h> 15#include <linux/key.h> 16#include <linux/bio.h> 17#include <linux/blkdev.h> 18#include <linux/mempool.h> 19#include <linux/slab.h> 20#include <linux/crypto.h> 21#include <linux/workqueue.h> 22#include <linux/kthread.h> 23#include <linux/backing-dev.h> 24#include <linux/atomic.h> 25#include <linux/scatterlist.h> 26#include <linux/rbtree.h> 27#include <linux/ctype.h> 28#include <asm/page.h> 29#include <asm/unaligned.h> 30#include <crypto/hash.h> 31#include <crypto/md5.h> 32#include <crypto/algapi.h> 33#include <crypto/skcipher.h> 34#include <crypto/aead.h> 35#include <crypto/authenc.h> 36#include <linux/rtnetlink.h> /* for struct rtattr and RTA macros only */ 37#include <linux/key-type.h> 38#include <keys/user-type.h> 39#include <keys/encrypted-type.h> 40 41#include <linux/device-mapper.h> 42 43#define DM_MSG_PREFIX "crypt" 44 45/* 46 * context holding the current state of a multi-part conversion 47 */ 48struct convert_context { 49 struct completion restart; 50 struct bio *bio_in; 51 struct bio *bio_out; 52 struct bvec_iter iter_in; 53 struct bvec_iter iter_out; 54 u64 cc_sector; 55 atomic_t cc_pending; 56 union { 57 struct skcipher_request *req; 58 struct aead_request *req_aead; 59 } r; 60 61}; 62 63/* 64 * per bio private data 65 */ 66struct dm_crypt_io { 67 struct crypt_config *cc; 68 struct bio *base_bio; 69 u8 *integrity_metadata; 70 bool integrity_metadata_from_pool:1; 71 bool in_tasklet:1; 72 73 struct work_struct work; 74 struct tasklet_struct tasklet; 75 76 struct convert_context ctx; 77 78 atomic_t io_pending; 79 blk_status_t error; 80 sector_t sector; 81 82 struct rb_node rb_node; 83} CRYPTO_MINALIGN_ATTR; 84 85struct dm_crypt_request { 86 struct convert_context *ctx; 87 struct scatterlist sg_in[4]; 88 struct scatterlist sg_out[4]; 89 u64 iv_sector; 90}; 91 92struct crypt_config; 93 94struct crypt_iv_operations { 95 int (*ctr)(struct crypt_config *cc, struct dm_target *ti, 96 const char *opts); 97 void (*dtr)(struct crypt_config *cc); 98 int (*init)(struct crypt_config *cc); 99 int (*wipe)(struct crypt_config *cc); 100 int (*generator)(struct crypt_config *cc, u8 *iv, 101 struct dm_crypt_request *dmreq); 102 int (*post)(struct crypt_config *cc, u8 *iv, 103 struct dm_crypt_request *dmreq); 104}; 105 106struct iv_benbi_private { 107 int shift; 108}; 109 110#define LMK_SEED_SIZE 64 /* hash + 0 */ 111struct iv_lmk_private { 112 struct crypto_shash *hash_tfm; 113 u8 *seed; 114}; 115 116#define TCW_WHITENING_SIZE 16 117struct iv_tcw_private { 118 struct crypto_shash *crc32_tfm; 119 u8 *iv_seed; 120 u8 *whitening; 121}; 122 123#define ELEPHANT_MAX_KEY_SIZE 32 124struct iv_elephant_private { 125 struct crypto_skcipher *tfm; 126}; 127 128/* 129 * Crypt: maps a linear range of a block device 130 * and encrypts / decrypts at the same time. 131 */ 132enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID, 133 DM_CRYPT_SAME_CPU, DM_CRYPT_NO_OFFLOAD, 134 DM_CRYPT_NO_READ_WORKQUEUE, DM_CRYPT_NO_WRITE_WORKQUEUE, 135 DM_CRYPT_WRITE_INLINE }; 136 137enum cipher_flags { 138 CRYPT_MODE_INTEGRITY_AEAD, /* Use authenticated mode for cihper */ 139 CRYPT_IV_LARGE_SECTORS, /* Calculate IV from sector_size, not 512B sectors */ 140 CRYPT_ENCRYPT_PREPROCESS, /* Must preprocess data for encryption (elephant) */ 141}; 142 143/* 144 * The fields in here must be read only after initialization. 145 */ 146struct crypt_config { 147 struct dm_dev *dev; 148 sector_t start; 149 150 struct percpu_counter n_allocated_pages; 151 152 struct workqueue_struct *io_queue; 153 struct workqueue_struct *crypt_queue; 154 155 spinlock_t write_thread_lock; 156 struct task_struct *write_thread; 157 struct rb_root write_tree; 158 159 char *cipher_string; 160 char *cipher_auth; 161 char *key_string; 162 163 const struct crypt_iv_operations *iv_gen_ops; 164 union { 165 struct iv_benbi_private benbi; 166 struct iv_lmk_private lmk; 167 struct iv_tcw_private tcw; 168 struct iv_elephant_private elephant; 169 } iv_gen_private; 170 u64 iv_offset; 171 unsigned int iv_size; 172 unsigned short int sector_size; 173 unsigned char sector_shift; 174 175 union { 176 struct crypto_skcipher **tfms; 177 struct crypto_aead **tfms_aead; 178 } cipher_tfm; 179 unsigned tfms_count; 180 unsigned long cipher_flags; 181 182 /* 183 * Layout of each crypto request: 184 * 185 * struct skcipher_request 186 * context 187 * padding 188 * struct dm_crypt_request 189 * padding 190 * IV 191 * 192 * The padding is added so that dm_crypt_request and the IV are 193 * correctly aligned. 194 */ 195 unsigned int dmreq_start; 196 197 unsigned int per_bio_data_size; 198 199 unsigned long flags; 200 unsigned int key_size; 201 unsigned int key_parts; /* independent parts in key buffer */ 202 unsigned int key_extra_size; /* additional keys length */ 203 unsigned int key_mac_size; /* MAC key size for authenc(...) */ 204 205 unsigned int integrity_tag_size; 206 unsigned int integrity_iv_size; 207 unsigned int on_disk_tag_size; 208 209 /* 210 * pool for per bio private data, crypto requests, 211 * encryption requeusts/buffer pages and integrity tags 212 */ 213 unsigned tag_pool_max_sectors; 214 mempool_t tag_pool; 215 mempool_t req_pool; 216 mempool_t page_pool; 217 218 struct bio_set bs; 219 struct mutex bio_alloc_lock; 220 221 u8 *authenc_key; /* space for keys in authenc() format (if used) */ 222 u8 key[]; 223}; 224 225#define MIN_IOS 64 226#define MAX_TAG_SIZE 480 227#define POOL_ENTRY_SIZE 512 228 229static DEFINE_SPINLOCK(dm_crypt_clients_lock); 230static unsigned dm_crypt_clients_n = 0; 231static volatile unsigned long dm_crypt_pages_per_client; 232#define DM_CRYPT_MEMORY_PERCENT 2 233#define DM_CRYPT_MIN_PAGES_PER_CLIENT (BIO_MAX_PAGES * 16) 234 235static void clone_init(struct dm_crypt_io *, struct bio *); 236static void kcryptd_queue_crypt(struct dm_crypt_io *io); 237static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 238 struct scatterlist *sg); 239 240static bool crypt_integrity_aead(struct crypt_config *cc); 241 242/* 243 * Use this to access cipher attributes that are independent of the key. 244 */ 245static struct crypto_skcipher *any_tfm(struct crypt_config *cc) 246{ 247 return cc->cipher_tfm.tfms[0]; 248} 249 250static struct crypto_aead *any_tfm_aead(struct crypt_config *cc) 251{ 252 return cc->cipher_tfm.tfms_aead[0]; 253} 254 255/* 256 * Different IV generation algorithms: 257 * 258 * plain: the initial vector is the 32-bit little-endian version of the sector 259 * number, padded with zeros if necessary. 260 * 261 * plain64: the initial vector is the 64-bit little-endian version of the sector 262 * number, padded with zeros if necessary. 263 * 264 * plain64be: the initial vector is the 64-bit big-endian version of the sector 265 * number, padded with zeros if necessary. 266 * 267 * essiv: "encrypted sector|salt initial vector", the sector number is 268 * encrypted with the bulk cipher using a salt as key. The salt 269 * should be derived from the bulk cipher's key via hashing. 270 * 271 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 272 * (needed for LRW-32-AES and possible other narrow block modes) 273 * 274 * null: the initial vector is always zero. Provides compatibility with 275 * obsolete loop_fish2 devices. Do not use for new devices. 276 * 277 * lmk: Compatible implementation of the block chaining mode used 278 * by the Loop-AES block device encryption system 279 * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/ 280 * It operates on full 512 byte sectors and uses CBC 281 * with an IV derived from the sector number, the data and 282 * optionally extra IV seed. 283 * This means that after decryption the first block 284 * of sector must be tweaked according to decrypted data. 285 * Loop-AES can use three encryption schemes: 286 * version 1: is plain aes-cbc mode 287 * version 2: uses 64 multikey scheme with lmk IV generator 288 * version 3: the same as version 2 with additional IV seed 289 * (it uses 65 keys, last key is used as IV seed) 290 * 291 * tcw: Compatible implementation of the block chaining mode used 292 * by the TrueCrypt device encryption system (prior to version 4.1). 293 * For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat 294 * It operates on full 512 byte sectors and uses CBC 295 * with an IV derived from initial key and the sector number. 296 * In addition, whitening value is applied on every sector, whitening 297 * is calculated from initial key, sector number and mixed using CRC32. 298 * Note that this encryption scheme is vulnerable to watermarking attacks 299 * and should be used for old compatible containers access only. 300 * 301 * eboiv: Encrypted byte-offset IV (used in Bitlocker in CBC mode) 302 * The IV is encrypted little-endian byte-offset (with the same key 303 * and cipher as the volume). 304 * 305 * elephant: The extended version of eboiv with additional Elephant diffuser 306 * used with Bitlocker CBC mode. 307 * This mode was used in older Windows systems 308 * https://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf 309 */ 310 311static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, 312 struct dm_crypt_request *dmreq) 313{ 314 memset(iv, 0, cc->iv_size); 315 *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff); 316 317 return 0; 318} 319 320static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv, 321 struct dm_crypt_request *dmreq) 322{ 323 memset(iv, 0, cc->iv_size); 324 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 325 326 return 0; 327} 328 329static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv, 330 struct dm_crypt_request *dmreq) 331{ 332 memset(iv, 0, cc->iv_size); 333 /* iv_size is at least of size u64; usually it is 16 bytes */ 334 *(__be64 *)&iv[cc->iv_size - sizeof(u64)] = cpu_to_be64(dmreq->iv_sector); 335 336 return 0; 337} 338 339static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, 340 struct dm_crypt_request *dmreq) 341{ 342 /* 343 * ESSIV encryption of the IV is now handled by the crypto API, 344 * so just pass the plain sector number here. 345 */ 346 memset(iv, 0, cc->iv_size); 347 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 348 349 return 0; 350} 351 352static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, 353 const char *opts) 354{ 355 unsigned bs; 356 int log; 357 358 if (crypt_integrity_aead(cc)) 359 bs = crypto_aead_blocksize(any_tfm_aead(cc)); 360 else 361 bs = crypto_skcipher_blocksize(any_tfm(cc)); 362 log = ilog2(bs); 363 364 /* we need to calculate how far we must shift the sector count 365 * to get the cipher block count, we use this shift in _gen */ 366 367 if (1 << log != bs) { 368 ti->error = "cypher blocksize is not a power of 2"; 369 return -EINVAL; 370 } 371 372 if (log > 9) { 373 ti->error = "cypher blocksize is > 512"; 374 return -EINVAL; 375 } 376 377 cc->iv_gen_private.benbi.shift = 9 - log; 378 379 return 0; 380} 381 382static void crypt_iv_benbi_dtr(struct crypt_config *cc) 383{ 384} 385 386static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, 387 struct dm_crypt_request *dmreq) 388{ 389 __be64 val; 390 391 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ 392 393 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1); 394 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); 395 396 return 0; 397} 398 399static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, 400 struct dm_crypt_request *dmreq) 401{ 402 memset(iv, 0, cc->iv_size); 403 404 return 0; 405} 406 407static void crypt_iv_lmk_dtr(struct crypt_config *cc) 408{ 409 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 410 411 if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm)) 412 crypto_free_shash(lmk->hash_tfm); 413 lmk->hash_tfm = NULL; 414 415 kfree_sensitive(lmk->seed); 416 lmk->seed = NULL; 417} 418 419static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti, 420 const char *opts) 421{ 422 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 423 424 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 425 ti->error = "Unsupported sector size for LMK"; 426 return -EINVAL; 427 } 428 429 lmk->hash_tfm = crypto_alloc_shash("md5", 0, 430 CRYPTO_ALG_ALLOCATES_MEMORY); 431 if (IS_ERR(lmk->hash_tfm)) { 432 ti->error = "Error initializing LMK hash"; 433 return PTR_ERR(lmk->hash_tfm); 434 } 435 436 /* No seed in LMK version 2 */ 437 if (cc->key_parts == cc->tfms_count) { 438 lmk->seed = NULL; 439 return 0; 440 } 441 442 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL); 443 if (!lmk->seed) { 444 crypt_iv_lmk_dtr(cc); 445 ti->error = "Error kmallocing seed storage in LMK"; 446 return -ENOMEM; 447 } 448 449 return 0; 450} 451 452static int crypt_iv_lmk_init(struct crypt_config *cc) 453{ 454 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 455 int subkey_size = cc->key_size / cc->key_parts; 456 457 /* LMK seed is on the position of LMK_KEYS + 1 key */ 458 if (lmk->seed) 459 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size), 460 crypto_shash_digestsize(lmk->hash_tfm)); 461 462 return 0; 463} 464 465static int crypt_iv_lmk_wipe(struct crypt_config *cc) 466{ 467 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 468 469 if (lmk->seed) 470 memset(lmk->seed, 0, LMK_SEED_SIZE); 471 472 return 0; 473} 474 475static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv, 476 struct dm_crypt_request *dmreq, 477 u8 *data) 478{ 479 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 480 SHASH_DESC_ON_STACK(desc, lmk->hash_tfm); 481 struct md5_state md5state; 482 __le32 buf[4]; 483 int i, r; 484 485 desc->tfm = lmk->hash_tfm; 486 487 r = crypto_shash_init(desc); 488 if (r) 489 return r; 490 491 if (lmk->seed) { 492 r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE); 493 if (r) 494 return r; 495 } 496 497 /* Sector is always 512B, block size 16, add data of blocks 1-31 */ 498 r = crypto_shash_update(desc, data + 16, 16 * 31); 499 if (r) 500 return r; 501 502 /* Sector is cropped to 56 bits here */ 503 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF); 504 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000); 505 buf[2] = cpu_to_le32(4024); 506 buf[3] = 0; 507 r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf)); 508 if (r) 509 return r; 510 511 /* No MD5 padding here */ 512 r = crypto_shash_export(desc, &md5state); 513 if (r) 514 return r; 515 516 for (i = 0; i < MD5_HASH_WORDS; i++) 517 __cpu_to_le32s(&md5state.hash[i]); 518 memcpy(iv, &md5state.hash, cc->iv_size); 519 520 return 0; 521} 522 523static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv, 524 struct dm_crypt_request *dmreq) 525{ 526 struct scatterlist *sg; 527 u8 *src; 528 int r = 0; 529 530 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 531 sg = crypt_get_sg_data(cc, dmreq->sg_in); 532 src = kmap_atomic(sg_page(sg)); 533 r = crypt_iv_lmk_one(cc, iv, dmreq, src + sg->offset); 534 kunmap_atomic(src); 535 } else 536 memset(iv, 0, cc->iv_size); 537 538 return r; 539} 540 541static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv, 542 struct dm_crypt_request *dmreq) 543{ 544 struct scatterlist *sg; 545 u8 *dst; 546 int r; 547 548 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) 549 return 0; 550 551 sg = crypt_get_sg_data(cc, dmreq->sg_out); 552 dst = kmap_atomic(sg_page(sg)); 553 r = crypt_iv_lmk_one(cc, iv, dmreq, dst + sg->offset); 554 555 /* Tweak the first block of plaintext sector */ 556 if (!r) 557 crypto_xor(dst + sg->offset, iv, cc->iv_size); 558 559 kunmap_atomic(dst); 560 return r; 561} 562 563static void crypt_iv_tcw_dtr(struct crypt_config *cc) 564{ 565 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 566 567 kfree_sensitive(tcw->iv_seed); 568 tcw->iv_seed = NULL; 569 kfree_sensitive(tcw->whitening); 570 tcw->whitening = NULL; 571 572 if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm)) 573 crypto_free_shash(tcw->crc32_tfm); 574 tcw->crc32_tfm = NULL; 575} 576 577static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti, 578 const char *opts) 579{ 580 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 581 582 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 583 ti->error = "Unsupported sector size for TCW"; 584 return -EINVAL; 585 } 586 587 if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) { 588 ti->error = "Wrong key size for TCW"; 589 return -EINVAL; 590 } 591 592 tcw->crc32_tfm = crypto_alloc_shash("crc32", 0, 593 CRYPTO_ALG_ALLOCATES_MEMORY); 594 if (IS_ERR(tcw->crc32_tfm)) { 595 ti->error = "Error initializing CRC32 in TCW"; 596 return PTR_ERR(tcw->crc32_tfm); 597 } 598 599 tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL); 600 tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL); 601 if (!tcw->iv_seed || !tcw->whitening) { 602 crypt_iv_tcw_dtr(cc); 603 ti->error = "Error allocating seed storage in TCW"; 604 return -ENOMEM; 605 } 606 607 return 0; 608} 609 610static int crypt_iv_tcw_init(struct crypt_config *cc) 611{ 612 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 613 int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE; 614 615 memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size); 616 memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size], 617 TCW_WHITENING_SIZE); 618 619 return 0; 620} 621 622static int crypt_iv_tcw_wipe(struct crypt_config *cc) 623{ 624 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 625 626 memset(tcw->iv_seed, 0, cc->iv_size); 627 memset(tcw->whitening, 0, TCW_WHITENING_SIZE); 628 629 return 0; 630} 631 632static int crypt_iv_tcw_whitening(struct crypt_config *cc, 633 struct dm_crypt_request *dmreq, 634 u8 *data) 635{ 636 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 637 __le64 sector = cpu_to_le64(dmreq->iv_sector); 638 u8 buf[TCW_WHITENING_SIZE]; 639 SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm); 640 int i, r; 641 642 /* xor whitening with sector number */ 643 crypto_xor_cpy(buf, tcw->whitening, (u8 *)§or, 8); 644 crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)§or, 8); 645 646 /* calculate crc32 for every 32bit part and xor it */ 647 desc->tfm = tcw->crc32_tfm; 648 for (i = 0; i < 4; i++) { 649 r = crypto_shash_init(desc); 650 if (r) 651 goto out; 652 r = crypto_shash_update(desc, &buf[i * 4], 4); 653 if (r) 654 goto out; 655 r = crypto_shash_final(desc, &buf[i * 4]); 656 if (r) 657 goto out; 658 } 659 crypto_xor(&buf[0], &buf[12], 4); 660 crypto_xor(&buf[4], &buf[8], 4); 661 662 /* apply whitening (8 bytes) to whole sector */ 663 for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++) 664 crypto_xor(data + i * 8, buf, 8); 665out: 666 memzero_explicit(buf, sizeof(buf)); 667 return r; 668} 669 670static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv, 671 struct dm_crypt_request *dmreq) 672{ 673 struct scatterlist *sg; 674 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 675 __le64 sector = cpu_to_le64(dmreq->iv_sector); 676 u8 *src; 677 int r = 0; 678 679 /* Remove whitening from ciphertext */ 680 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 681 sg = crypt_get_sg_data(cc, dmreq->sg_in); 682 src = kmap_atomic(sg_page(sg)); 683 r = crypt_iv_tcw_whitening(cc, dmreq, src + sg->offset); 684 kunmap_atomic(src); 685 } 686 687 /* Calculate IV */ 688 crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)§or, 8); 689 if (cc->iv_size > 8) 690 crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)§or, 691 cc->iv_size - 8); 692 693 return r; 694} 695 696static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv, 697 struct dm_crypt_request *dmreq) 698{ 699 struct scatterlist *sg; 700 u8 *dst; 701 int r; 702 703 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 704 return 0; 705 706 /* Apply whitening on ciphertext */ 707 sg = crypt_get_sg_data(cc, dmreq->sg_out); 708 dst = kmap_atomic(sg_page(sg)); 709 r = crypt_iv_tcw_whitening(cc, dmreq, dst + sg->offset); 710 kunmap_atomic(dst); 711 712 return r; 713} 714 715static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv, 716 struct dm_crypt_request *dmreq) 717{ 718 /* Used only for writes, there must be an additional space to store IV */ 719 get_random_bytes(iv, cc->iv_size); 720 return 0; 721} 722 723static int crypt_iv_eboiv_ctr(struct crypt_config *cc, struct dm_target *ti, 724 const char *opts) 725{ 726 if (crypt_integrity_aead(cc)) { 727 ti->error = "AEAD transforms not supported for EBOIV"; 728 return -EINVAL; 729 } 730 731 if (crypto_skcipher_blocksize(any_tfm(cc)) != cc->iv_size) { 732 ti->error = "Block size of EBOIV cipher does " 733 "not match IV size of block cipher"; 734 return -EINVAL; 735 } 736 737 return 0; 738} 739 740static int crypt_iv_eboiv_gen(struct crypt_config *cc, u8 *iv, 741 struct dm_crypt_request *dmreq) 742{ 743 u8 buf[MAX_CIPHER_BLOCKSIZE] __aligned(__alignof__(__le64)); 744 struct skcipher_request *req; 745 struct scatterlist src, dst; 746 DECLARE_CRYPTO_WAIT(wait); 747 int err; 748 749 req = skcipher_request_alloc(any_tfm(cc), GFP_NOIO); 750 if (!req) 751 return -ENOMEM; 752 753 memset(buf, 0, cc->iv_size); 754 *(__le64 *)buf = cpu_to_le64(dmreq->iv_sector * cc->sector_size); 755 756 sg_init_one(&src, page_address(ZERO_PAGE(0)), cc->iv_size); 757 sg_init_one(&dst, iv, cc->iv_size); 758 skcipher_request_set_crypt(req, &src, &dst, cc->iv_size, buf); 759 skcipher_request_set_callback(req, 0, crypto_req_done, &wait); 760 err = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 761 skcipher_request_free(req); 762 763 return err; 764} 765 766static void crypt_iv_elephant_dtr(struct crypt_config *cc) 767{ 768 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 769 770 crypto_free_skcipher(elephant->tfm); 771 elephant->tfm = NULL; 772} 773 774static int crypt_iv_elephant_ctr(struct crypt_config *cc, struct dm_target *ti, 775 const char *opts) 776{ 777 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 778 int r; 779 780 elephant->tfm = crypto_alloc_skcipher("ecb(aes)", 0, 781 CRYPTO_ALG_ALLOCATES_MEMORY); 782 if (IS_ERR(elephant->tfm)) { 783 r = PTR_ERR(elephant->tfm); 784 elephant->tfm = NULL; 785 return r; 786 } 787 788 r = crypt_iv_eboiv_ctr(cc, ti, NULL); 789 if (r) 790 crypt_iv_elephant_dtr(cc); 791 return r; 792} 793 794static void diffuser_disk_to_cpu(u32 *d, size_t n) 795{ 796#ifndef __LITTLE_ENDIAN 797 int i; 798 799 for (i = 0; i < n; i++) 800 d[i] = le32_to_cpu((__le32)d[i]); 801#endif 802} 803 804static void diffuser_cpu_to_disk(__le32 *d, size_t n) 805{ 806#ifndef __LITTLE_ENDIAN 807 int i; 808 809 for (i = 0; i < n; i++) 810 d[i] = cpu_to_le32((u32)d[i]); 811#endif 812} 813 814static void diffuser_a_decrypt(u32 *d, size_t n) 815{ 816 int i, i1, i2, i3; 817 818 for (i = 0; i < 5; i++) { 819 i1 = 0; 820 i2 = n - 2; 821 i3 = n - 5; 822 823 while (i1 < (n - 1)) { 824 d[i1] += d[i2] ^ (d[i3] << 9 | d[i3] >> 23); 825 i1++; i2++; i3++; 826 827 if (i3 >= n) 828 i3 -= n; 829 830 d[i1] += d[i2] ^ d[i3]; 831 i1++; i2++; i3++; 832 833 if (i2 >= n) 834 i2 -= n; 835 836 d[i1] += d[i2] ^ (d[i3] << 13 | d[i3] >> 19); 837 i1++; i2++; i3++; 838 839 d[i1] += d[i2] ^ d[i3]; 840 i1++; i2++; i3++; 841 } 842 } 843} 844 845static void diffuser_a_encrypt(u32 *d, size_t n) 846{ 847 int i, i1, i2, i3; 848 849 for (i = 0; i < 5; i++) { 850 i1 = n - 1; 851 i2 = n - 2 - 1; 852 i3 = n - 5 - 1; 853 854 while (i1 > 0) { 855 d[i1] -= d[i2] ^ d[i3]; 856 i1--; i2--; i3--; 857 858 d[i1] -= d[i2] ^ (d[i3] << 13 | d[i3] >> 19); 859 i1--; i2--; i3--; 860 861 if (i2 < 0) 862 i2 += n; 863 864 d[i1] -= d[i2] ^ d[i3]; 865 i1--; i2--; i3--; 866 867 if (i3 < 0) 868 i3 += n; 869 870 d[i1] -= d[i2] ^ (d[i3] << 9 | d[i3] >> 23); 871 i1--; i2--; i3--; 872 } 873 } 874} 875 876static void diffuser_b_decrypt(u32 *d, size_t n) 877{ 878 int i, i1, i2, i3; 879 880 for (i = 0; i < 3; i++) { 881 i1 = 0; 882 i2 = 2; 883 i3 = 5; 884 885 while (i1 < (n - 1)) { 886 d[i1] += d[i2] ^ d[i3]; 887 i1++; i2++; i3++; 888 889 d[i1] += d[i2] ^ (d[i3] << 10 | d[i3] >> 22); 890 i1++; i2++; i3++; 891 892 if (i2 >= n) 893 i2 -= n; 894 895 d[i1] += d[i2] ^ d[i3]; 896 i1++; i2++; i3++; 897 898 if (i3 >= n) 899 i3 -= n; 900 901 d[i1] += d[i2] ^ (d[i3] << 25 | d[i3] >> 7); 902 i1++; i2++; i3++; 903 } 904 } 905} 906 907static void diffuser_b_encrypt(u32 *d, size_t n) 908{ 909 int i, i1, i2, i3; 910 911 for (i = 0; i < 3; i++) { 912 i1 = n - 1; 913 i2 = 2 - 1; 914 i3 = 5 - 1; 915 916 while (i1 > 0) { 917 d[i1] -= d[i2] ^ (d[i3] << 25 | d[i3] >> 7); 918 i1--; i2--; i3--; 919 920 if (i3 < 0) 921 i3 += n; 922 923 d[i1] -= d[i2] ^ d[i3]; 924 i1--; i2--; i3--; 925 926 if (i2 < 0) 927 i2 += n; 928 929 d[i1] -= d[i2] ^ (d[i3] << 10 | d[i3] >> 22); 930 i1--; i2--; i3--; 931 932 d[i1] -= d[i2] ^ d[i3]; 933 i1--; i2--; i3--; 934 } 935 } 936} 937 938static int crypt_iv_elephant(struct crypt_config *cc, struct dm_crypt_request *dmreq) 939{ 940 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 941 u8 *es, *ks, *data, *data2, *data_offset; 942 struct skcipher_request *req; 943 struct scatterlist *sg, *sg2, src, dst; 944 DECLARE_CRYPTO_WAIT(wait); 945 int i, r; 946 947 req = skcipher_request_alloc(elephant->tfm, GFP_NOIO); 948 es = kzalloc(16, GFP_NOIO); /* Key for AES */ 949 ks = kzalloc(32, GFP_NOIO); /* Elephant sector key */ 950 951 if (!req || !es || !ks) { 952 r = -ENOMEM; 953 goto out; 954 } 955 956 *(__le64 *)es = cpu_to_le64(dmreq->iv_sector * cc->sector_size); 957 958 /* E(Ks, e(s)) */ 959 sg_init_one(&src, es, 16); 960 sg_init_one(&dst, ks, 16); 961 skcipher_request_set_crypt(req, &src, &dst, 16, NULL); 962 skcipher_request_set_callback(req, 0, crypto_req_done, &wait); 963 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 964 if (r) 965 goto out; 966 967 /* E(Ks, e'(s)) */ 968 es[15] = 0x80; 969 sg_init_one(&dst, &ks[16], 16); 970 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 971 if (r) 972 goto out; 973 974 sg = crypt_get_sg_data(cc, dmreq->sg_out); 975 data = kmap_atomic(sg_page(sg)); 976 data_offset = data + sg->offset; 977 978 /* Cannot modify original bio, copy to sg_out and apply Elephant to it */ 979 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 980 sg2 = crypt_get_sg_data(cc, dmreq->sg_in); 981 data2 = kmap_atomic(sg_page(sg2)); 982 memcpy(data_offset, data2 + sg2->offset, cc->sector_size); 983 kunmap_atomic(data2); 984 } 985 986 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 987 diffuser_disk_to_cpu((u32*)data_offset, cc->sector_size / sizeof(u32)); 988 diffuser_b_decrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 989 diffuser_a_decrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 990 diffuser_cpu_to_disk((__le32*)data_offset, cc->sector_size / sizeof(u32)); 991 } 992 993 for (i = 0; i < (cc->sector_size / 32); i++) 994 crypto_xor(data_offset + i * 32, ks, 32); 995 996 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 997 diffuser_disk_to_cpu((u32*)data_offset, cc->sector_size / sizeof(u32)); 998 diffuser_a_encrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 999 diffuser_b_encrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 1000 diffuser_cpu_to_disk((__le32*)data_offset, cc->sector_size / sizeof(u32)); 1001 } 1002 1003 kunmap_atomic(data); 1004out: 1005 kfree_sensitive(ks); 1006 kfree_sensitive(es); 1007 skcipher_request_free(req); 1008 return r; 1009} 1010 1011static int crypt_iv_elephant_gen(struct crypt_config *cc, u8 *iv, 1012 struct dm_crypt_request *dmreq) 1013{ 1014 int r; 1015 1016 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 1017 r = crypt_iv_elephant(cc, dmreq); 1018 if (r) 1019 return r; 1020 } 1021 1022 return crypt_iv_eboiv_gen(cc, iv, dmreq); 1023} 1024 1025static int crypt_iv_elephant_post(struct crypt_config *cc, u8 *iv, 1026 struct dm_crypt_request *dmreq) 1027{ 1028 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 1029 return crypt_iv_elephant(cc, dmreq); 1030 1031 return 0; 1032} 1033 1034static int crypt_iv_elephant_init(struct crypt_config *cc) 1035{ 1036 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 1037 int key_offset = cc->key_size - cc->key_extra_size; 1038 1039 return crypto_skcipher_setkey(elephant->tfm, &cc->key[key_offset], cc->key_extra_size); 1040} 1041 1042static int crypt_iv_elephant_wipe(struct crypt_config *cc) 1043{ 1044 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 1045 u8 key[ELEPHANT_MAX_KEY_SIZE]; 1046 1047 memset(key, 0, cc->key_extra_size); 1048 return crypto_skcipher_setkey(elephant->tfm, key, cc->key_extra_size); 1049} 1050 1051static const struct crypt_iv_operations crypt_iv_plain_ops = { 1052 .generator = crypt_iv_plain_gen 1053}; 1054 1055static const struct crypt_iv_operations crypt_iv_plain64_ops = { 1056 .generator = crypt_iv_plain64_gen 1057}; 1058 1059static const struct crypt_iv_operations crypt_iv_plain64be_ops = { 1060 .generator = crypt_iv_plain64be_gen 1061}; 1062 1063static const struct crypt_iv_operations crypt_iv_essiv_ops = { 1064 .generator = crypt_iv_essiv_gen 1065}; 1066 1067static const struct crypt_iv_operations crypt_iv_benbi_ops = { 1068 .ctr = crypt_iv_benbi_ctr, 1069 .dtr = crypt_iv_benbi_dtr, 1070 .generator = crypt_iv_benbi_gen 1071}; 1072 1073static const struct crypt_iv_operations crypt_iv_null_ops = { 1074 .generator = crypt_iv_null_gen 1075}; 1076 1077static const struct crypt_iv_operations crypt_iv_lmk_ops = { 1078 .ctr = crypt_iv_lmk_ctr, 1079 .dtr = crypt_iv_lmk_dtr, 1080 .init = crypt_iv_lmk_init, 1081 .wipe = crypt_iv_lmk_wipe, 1082 .generator = crypt_iv_lmk_gen, 1083 .post = crypt_iv_lmk_post 1084}; 1085 1086static const struct crypt_iv_operations crypt_iv_tcw_ops = { 1087 .ctr = crypt_iv_tcw_ctr, 1088 .dtr = crypt_iv_tcw_dtr, 1089 .init = crypt_iv_tcw_init, 1090 .wipe = crypt_iv_tcw_wipe, 1091 .generator = crypt_iv_tcw_gen, 1092 .post = crypt_iv_tcw_post 1093}; 1094 1095static struct crypt_iv_operations crypt_iv_random_ops = { 1096 .generator = crypt_iv_random_gen 1097}; 1098 1099static struct crypt_iv_operations crypt_iv_eboiv_ops = { 1100 .ctr = crypt_iv_eboiv_ctr, 1101 .generator = crypt_iv_eboiv_gen 1102}; 1103 1104static struct crypt_iv_operations crypt_iv_elephant_ops = { 1105 .ctr = crypt_iv_elephant_ctr, 1106 .dtr = crypt_iv_elephant_dtr, 1107 .init = crypt_iv_elephant_init, 1108 .wipe = crypt_iv_elephant_wipe, 1109 .generator = crypt_iv_elephant_gen, 1110 .post = crypt_iv_elephant_post 1111}; 1112 1113/* 1114 * Integrity extensions 1115 */ 1116static bool crypt_integrity_aead(struct crypt_config *cc) 1117{ 1118 return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 1119} 1120 1121static bool crypt_integrity_hmac(struct crypt_config *cc) 1122{ 1123 return crypt_integrity_aead(cc) && cc->key_mac_size; 1124} 1125 1126/* Get sg containing data */ 1127static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 1128 struct scatterlist *sg) 1129{ 1130 if (unlikely(crypt_integrity_aead(cc))) 1131 return &sg[2]; 1132 1133 return sg; 1134} 1135 1136static int dm_crypt_integrity_io_alloc(struct dm_crypt_io *io, struct bio *bio) 1137{ 1138 struct bio_integrity_payload *bip; 1139 unsigned int tag_len; 1140 int ret; 1141 1142 if (!bio_sectors(bio) || !io->cc->on_disk_tag_size) 1143 return 0; 1144 1145 bip = bio_integrity_alloc(bio, GFP_NOIO, 1); 1146 if (IS_ERR(bip)) 1147 return PTR_ERR(bip); 1148 1149 tag_len = io->cc->on_disk_tag_size * (bio_sectors(bio) >> io->cc->sector_shift); 1150 1151 bip->bip_iter.bi_size = tag_len; 1152 bip->bip_iter.bi_sector = io->cc->start + io->sector; 1153 1154 ret = bio_integrity_add_page(bio, virt_to_page(io->integrity_metadata), 1155 tag_len, offset_in_page(io->integrity_metadata)); 1156 if (unlikely(ret != tag_len)) 1157 return -ENOMEM; 1158 1159 return 0; 1160} 1161 1162static int crypt_integrity_ctr(struct crypt_config *cc, struct dm_target *ti) 1163{ 1164#ifdef CONFIG_BLK_DEV_INTEGRITY 1165 struct blk_integrity *bi = blk_get_integrity(cc->dev->bdev->bd_disk); 1166 struct mapped_device *md = dm_table_get_md(ti->table); 1167 1168 /* From now we require underlying device with our integrity profile */ 1169 if (!bi || strcasecmp(bi->profile->name, "DM-DIF-EXT-TAG")) { 1170 ti->error = "Integrity profile not supported."; 1171 return -EINVAL; 1172 } 1173 1174 if (bi->tag_size != cc->on_disk_tag_size || 1175 bi->tuple_size != cc->on_disk_tag_size) { 1176 ti->error = "Integrity profile tag size mismatch."; 1177 return -EINVAL; 1178 } 1179 if (1 << bi->interval_exp != cc->sector_size) { 1180 ti->error = "Integrity profile sector size mismatch."; 1181 return -EINVAL; 1182 } 1183 1184 if (crypt_integrity_aead(cc)) { 1185 cc->integrity_tag_size = cc->on_disk_tag_size - cc->integrity_iv_size; 1186 DMDEBUG("%s: Integrity AEAD, tag size %u, IV size %u.", dm_device_name(md), 1187 cc->integrity_tag_size, cc->integrity_iv_size); 1188 1189 if (crypto_aead_setauthsize(any_tfm_aead(cc), cc->integrity_tag_size)) { 1190 ti->error = "Integrity AEAD auth tag size is not supported."; 1191 return -EINVAL; 1192 } 1193 } else if (cc->integrity_iv_size) 1194 DMDEBUG("%s: Additional per-sector space %u bytes for IV.", dm_device_name(md), 1195 cc->integrity_iv_size); 1196 1197 if ((cc->integrity_tag_size + cc->integrity_iv_size) != bi->tag_size) { 1198 ti->error = "Not enough space for integrity tag in the profile."; 1199 return -EINVAL; 1200 } 1201 1202 return 0; 1203#else 1204 ti->error = "Integrity profile not supported."; 1205 return -EINVAL; 1206#endif 1207} 1208 1209static void crypt_convert_init(struct crypt_config *cc, 1210 struct convert_context *ctx, 1211 struct bio *bio_out, struct bio *bio_in, 1212 sector_t sector) 1213{ 1214 ctx->bio_in = bio_in; 1215 ctx->bio_out = bio_out; 1216 if (bio_in) 1217 ctx->iter_in = bio_in->bi_iter; 1218 if (bio_out) 1219 ctx->iter_out = bio_out->bi_iter; 1220 ctx->cc_sector = sector + cc->iv_offset; 1221 init_completion(&ctx->restart); 1222} 1223 1224static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc, 1225 void *req) 1226{ 1227 return (struct dm_crypt_request *)((char *)req + cc->dmreq_start); 1228} 1229 1230static void *req_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq) 1231{ 1232 return (void *)((char *)dmreq - cc->dmreq_start); 1233} 1234 1235static u8 *iv_of_dmreq(struct crypt_config *cc, 1236 struct dm_crypt_request *dmreq) 1237{ 1238 if (crypt_integrity_aead(cc)) 1239 return (u8 *)ALIGN((unsigned long)(dmreq + 1), 1240 crypto_aead_alignmask(any_tfm_aead(cc)) + 1); 1241 else 1242 return (u8 *)ALIGN((unsigned long)(dmreq + 1), 1243 crypto_skcipher_alignmask(any_tfm(cc)) + 1); 1244} 1245 1246static u8 *org_iv_of_dmreq(struct crypt_config *cc, 1247 struct dm_crypt_request *dmreq) 1248{ 1249 return iv_of_dmreq(cc, dmreq) + cc->iv_size; 1250} 1251 1252static __le64 *org_sector_of_dmreq(struct crypt_config *cc, 1253 struct dm_crypt_request *dmreq) 1254{ 1255 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + cc->iv_size; 1256 return (__le64 *) ptr; 1257} 1258 1259static unsigned int *org_tag_of_dmreq(struct crypt_config *cc, 1260 struct dm_crypt_request *dmreq) 1261{ 1262 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + 1263 cc->iv_size + sizeof(uint64_t); 1264 return (unsigned int*)ptr; 1265} 1266 1267static void *tag_from_dmreq(struct crypt_config *cc, 1268 struct dm_crypt_request *dmreq) 1269{ 1270 struct convert_context *ctx = dmreq->ctx; 1271 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 1272 1273 return &io->integrity_metadata[*org_tag_of_dmreq(cc, dmreq) * 1274 cc->on_disk_tag_size]; 1275} 1276 1277static void *iv_tag_from_dmreq(struct crypt_config *cc, 1278 struct dm_crypt_request *dmreq) 1279{ 1280 return tag_from_dmreq(cc, dmreq) + cc->integrity_tag_size; 1281} 1282 1283static int crypt_convert_block_aead(struct crypt_config *cc, 1284 struct convert_context *ctx, 1285 struct aead_request *req, 1286 unsigned int tag_offset) 1287{ 1288 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1289 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1290 struct dm_crypt_request *dmreq; 1291 u8 *iv, *org_iv, *tag_iv, *tag; 1292 __le64 *sector; 1293 int r = 0; 1294 1295 BUG_ON(cc->integrity_iv_size && cc->integrity_iv_size != cc->iv_size); 1296 1297 /* Reject unexpected unaligned bio. */ 1298 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1299 return -EIO; 1300 1301 dmreq = dmreq_of_req(cc, req); 1302 dmreq->iv_sector = ctx->cc_sector; 1303 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1304 dmreq->iv_sector >>= cc->sector_shift; 1305 dmreq->ctx = ctx; 1306 1307 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1308 1309 sector = org_sector_of_dmreq(cc, dmreq); 1310 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1311 1312 iv = iv_of_dmreq(cc, dmreq); 1313 org_iv = org_iv_of_dmreq(cc, dmreq); 1314 tag = tag_from_dmreq(cc, dmreq); 1315 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1316 1317 /* AEAD request: 1318 * |----- AAD -------|------ DATA -------|-- AUTH TAG --| 1319 * | (authenticated) | (auth+encryption) | | 1320 * | sector_LE | IV | sector in/out | tag in/out | 1321 */ 1322 sg_init_table(dmreq->sg_in, 4); 1323 sg_set_buf(&dmreq->sg_in[0], sector, sizeof(uint64_t)); 1324 sg_set_buf(&dmreq->sg_in[1], org_iv, cc->iv_size); 1325 sg_set_page(&dmreq->sg_in[2], bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1326 sg_set_buf(&dmreq->sg_in[3], tag, cc->integrity_tag_size); 1327 1328 sg_init_table(dmreq->sg_out, 4); 1329 sg_set_buf(&dmreq->sg_out[0], sector, sizeof(uint64_t)); 1330 sg_set_buf(&dmreq->sg_out[1], org_iv, cc->iv_size); 1331 sg_set_page(&dmreq->sg_out[2], bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1332 sg_set_buf(&dmreq->sg_out[3], tag, cc->integrity_tag_size); 1333 1334 if (cc->iv_gen_ops) { 1335 /* For READs use IV stored in integrity metadata */ 1336 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1337 memcpy(org_iv, tag_iv, cc->iv_size); 1338 } else { 1339 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1340 if (r < 0) 1341 return r; 1342 /* Store generated IV in integrity metadata */ 1343 if (cc->integrity_iv_size) 1344 memcpy(tag_iv, org_iv, cc->iv_size); 1345 } 1346 /* Working copy of IV, to be modified in crypto API */ 1347 memcpy(iv, org_iv, cc->iv_size); 1348 } 1349 1350 aead_request_set_ad(req, sizeof(uint64_t) + cc->iv_size); 1351 if (bio_data_dir(ctx->bio_in) == WRITE) { 1352 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out, 1353 cc->sector_size, iv); 1354 r = crypto_aead_encrypt(req); 1355 if (cc->integrity_tag_size + cc->integrity_iv_size != cc->on_disk_tag_size) 1356 memset(tag + cc->integrity_tag_size + cc->integrity_iv_size, 0, 1357 cc->on_disk_tag_size - (cc->integrity_tag_size + cc->integrity_iv_size)); 1358 } else { 1359 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out, 1360 cc->sector_size + cc->integrity_tag_size, iv); 1361 r = crypto_aead_decrypt(req); 1362 } 1363 1364 if (r == -EBADMSG) { 1365 char b[BDEVNAME_SIZE]; 1366 DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu", bio_devname(ctx->bio_in, b), 1367 (unsigned long long)le64_to_cpu(*sector)); 1368 } 1369 1370 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1371 r = cc->iv_gen_ops->post(cc, org_iv, dmreq); 1372 1373 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1374 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1375 1376 return r; 1377} 1378 1379static int crypt_convert_block_skcipher(struct crypt_config *cc, 1380 struct convert_context *ctx, 1381 struct skcipher_request *req, 1382 unsigned int tag_offset) 1383{ 1384 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1385 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1386 struct scatterlist *sg_in, *sg_out; 1387 struct dm_crypt_request *dmreq; 1388 u8 *iv, *org_iv, *tag_iv; 1389 __le64 *sector; 1390 int r = 0; 1391 1392 /* Reject unexpected unaligned bio. */ 1393 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1394 return -EIO; 1395 1396 dmreq = dmreq_of_req(cc, req); 1397 dmreq->iv_sector = ctx->cc_sector; 1398 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1399 dmreq->iv_sector >>= cc->sector_shift; 1400 dmreq->ctx = ctx; 1401 1402 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1403 1404 iv = iv_of_dmreq(cc, dmreq); 1405 org_iv = org_iv_of_dmreq(cc, dmreq); 1406 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1407 1408 sector = org_sector_of_dmreq(cc, dmreq); 1409 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1410 1411 /* For skcipher we use only the first sg item */ 1412 sg_in = &dmreq->sg_in[0]; 1413 sg_out = &dmreq->sg_out[0]; 1414 1415 sg_init_table(sg_in, 1); 1416 sg_set_page(sg_in, bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1417 1418 sg_init_table(sg_out, 1); 1419 sg_set_page(sg_out, bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1420 1421 if (cc->iv_gen_ops) { 1422 /* For READs use IV stored in integrity metadata */ 1423 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1424 memcpy(org_iv, tag_iv, cc->integrity_iv_size); 1425 } else { 1426 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1427 if (r < 0) 1428 return r; 1429 /* Data can be already preprocessed in generator */ 1430 if (test_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags)) 1431 sg_in = sg_out; 1432 /* Store generated IV in integrity metadata */ 1433 if (cc->integrity_iv_size) 1434 memcpy(tag_iv, org_iv, cc->integrity_iv_size); 1435 } 1436 /* Working copy of IV, to be modified in crypto API */ 1437 memcpy(iv, org_iv, cc->iv_size); 1438 } 1439 1440 skcipher_request_set_crypt(req, sg_in, sg_out, cc->sector_size, iv); 1441 1442 if (bio_data_dir(ctx->bio_in) == WRITE) 1443 r = crypto_skcipher_encrypt(req); 1444 else 1445 r = crypto_skcipher_decrypt(req); 1446 1447 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1448 r = cc->iv_gen_ops->post(cc, org_iv, dmreq); 1449 1450 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1451 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1452 1453 return r; 1454} 1455 1456static void kcryptd_async_done(struct crypto_async_request *async_req, 1457 int error); 1458 1459static int crypt_alloc_req_skcipher(struct crypt_config *cc, 1460 struct convert_context *ctx) 1461{ 1462 unsigned key_index = ctx->cc_sector & (cc->tfms_count - 1); 1463 1464 if (!ctx->r.req) { 1465 ctx->r.req = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1466 if (!ctx->r.req) 1467 return -ENOMEM; 1468 } 1469 1470 skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]); 1471 1472 /* 1473 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1474 * requests if driver request queue is full. 1475 */ 1476 skcipher_request_set_callback(ctx->r.req, 1477 CRYPTO_TFM_REQ_MAY_BACKLOG, 1478 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req)); 1479 1480 return 0; 1481} 1482 1483static int crypt_alloc_req_aead(struct crypt_config *cc, 1484 struct convert_context *ctx) 1485{ 1486 if (!ctx->r.req_aead) { 1487 ctx->r.req_aead = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1488 if (!ctx->r.req_aead) 1489 return -ENOMEM; 1490 } 1491 1492 aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]); 1493 1494 /* 1495 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1496 * requests if driver request queue is full. 1497 */ 1498 aead_request_set_callback(ctx->r.req_aead, 1499 CRYPTO_TFM_REQ_MAY_BACKLOG, 1500 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead)); 1501 1502 return 0; 1503} 1504 1505static int crypt_alloc_req(struct crypt_config *cc, 1506 struct convert_context *ctx) 1507{ 1508 if (crypt_integrity_aead(cc)) 1509 return crypt_alloc_req_aead(cc, ctx); 1510 else 1511 return crypt_alloc_req_skcipher(cc, ctx); 1512} 1513 1514static void crypt_free_req_skcipher(struct crypt_config *cc, 1515 struct skcipher_request *req, struct bio *base_bio) 1516{ 1517 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1518 1519 if ((struct skcipher_request *)(io + 1) != req) 1520 mempool_free(req, &cc->req_pool); 1521} 1522 1523static void crypt_free_req_aead(struct crypt_config *cc, 1524 struct aead_request *req, struct bio *base_bio) 1525{ 1526 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1527 1528 if ((struct aead_request *)(io + 1) != req) 1529 mempool_free(req, &cc->req_pool); 1530} 1531 1532static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio) 1533{ 1534 if (crypt_integrity_aead(cc)) 1535 crypt_free_req_aead(cc, req, base_bio); 1536 else 1537 crypt_free_req_skcipher(cc, req, base_bio); 1538} 1539 1540/* 1541 * Encrypt / decrypt data from one bio to another one (can be the same one) 1542 */ 1543static blk_status_t crypt_convert(struct crypt_config *cc, 1544 struct convert_context *ctx, bool atomic, bool reset_pending) 1545{ 1546 unsigned int tag_offset = 0; 1547 unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT; 1548 int r; 1549 1550 /* 1551 * if reset_pending is set we are dealing with the bio for the first time, 1552 * else we're continuing to work on the previous bio, so don't mess with 1553 * the cc_pending counter 1554 */ 1555 if (reset_pending) 1556 atomic_set(&ctx->cc_pending, 1); 1557 1558 while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) { 1559 1560 r = crypt_alloc_req(cc, ctx); 1561 if (r) { 1562 complete(&ctx->restart); 1563 return BLK_STS_DEV_RESOURCE; 1564 } 1565 1566 atomic_inc(&ctx->cc_pending); 1567 1568 if (crypt_integrity_aead(cc)) 1569 r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, tag_offset); 1570 else 1571 r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, tag_offset); 1572 1573 switch (r) { 1574 /* 1575 * The request was queued by a crypto driver 1576 * but the driver request queue is full, let's wait. 1577 */ 1578 case -EBUSY: 1579 if (in_interrupt()) { 1580 if (try_wait_for_completion(&ctx->restart)) { 1581 /* 1582 * we don't have to block to wait for completion, 1583 * so proceed 1584 */ 1585 } else { 1586 /* 1587 * we can't wait for completion without blocking 1588 * exit and continue processing in a workqueue 1589 */ 1590 ctx->r.req = NULL; 1591 ctx->cc_sector += sector_step; 1592 tag_offset++; 1593 return BLK_STS_DEV_RESOURCE; 1594 } 1595 } else { 1596 wait_for_completion(&ctx->restart); 1597 } 1598 reinit_completion(&ctx->restart); 1599 fallthrough; 1600 /* 1601 * The request is queued and processed asynchronously, 1602 * completion function kcryptd_async_done() will be called. 1603 */ 1604 case -EINPROGRESS: 1605 ctx->r.req = NULL; 1606 ctx->cc_sector += sector_step; 1607 tag_offset++; 1608 continue; 1609 /* 1610 * The request was already processed (synchronously). 1611 */ 1612 case 0: 1613 atomic_dec(&ctx->cc_pending); 1614 ctx->cc_sector += sector_step; 1615 tag_offset++; 1616 if (!atomic) 1617 cond_resched(); 1618 continue; 1619 /* 1620 * There was a data integrity error. 1621 */ 1622 case -EBADMSG: 1623 atomic_dec(&ctx->cc_pending); 1624 return BLK_STS_PROTECTION; 1625 /* 1626 * There was an error while processing the request. 1627 */ 1628 default: 1629 atomic_dec(&ctx->cc_pending); 1630 return BLK_STS_IOERR; 1631 } 1632 } 1633 1634 return 0; 1635} 1636 1637static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone); 1638 1639/* 1640 * Generate a new unfragmented bio with the given size 1641 * This should never violate the device limitations (but only because 1642 * max_segment_size is being constrained to PAGE_SIZE). 1643 * 1644 * This function may be called concurrently. If we allocate from the mempool 1645 * concurrently, there is a possibility of deadlock. For example, if we have 1646 * mempool of 256 pages, two processes, each wanting 256, pages allocate from 1647 * the mempool concurrently, it may deadlock in a situation where both processes 1648 * have allocated 128 pages and the mempool is exhausted. 1649 * 1650 * In order to avoid this scenario we allocate the pages under a mutex. 1651 * 1652 * In order to not degrade performance with excessive locking, we try 1653 * non-blocking allocations without a mutex first but on failure we fallback 1654 * to blocking allocations with a mutex. 1655 */ 1656static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size) 1657{ 1658 struct crypt_config *cc = io->cc; 1659 struct bio *clone; 1660 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; 1661 gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM; 1662 unsigned i, len, remaining_size; 1663 struct page *page; 1664 1665retry: 1666 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1667 mutex_lock(&cc->bio_alloc_lock); 1668 1669 clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, &cc->bs); 1670 if (!clone) 1671 goto out; 1672 1673 clone_init(io, clone); 1674 1675 remaining_size = size; 1676 1677 for (i = 0; i < nr_iovecs; i++) { 1678 page = mempool_alloc(&cc->page_pool, gfp_mask); 1679 if (!page) { 1680 crypt_free_buffer_pages(cc, clone); 1681 bio_put(clone); 1682 gfp_mask |= __GFP_DIRECT_RECLAIM; 1683 goto retry; 1684 } 1685 1686 len = (remaining_size > PAGE_SIZE) ? PAGE_SIZE : remaining_size; 1687 1688 bio_add_page(clone, page, len, 0); 1689 1690 remaining_size -= len; 1691 } 1692 1693 /* Allocate space for integrity tags */ 1694 if (dm_crypt_integrity_io_alloc(io, clone)) { 1695 crypt_free_buffer_pages(cc, clone); 1696 bio_put(clone); 1697 clone = NULL; 1698 } 1699out: 1700 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1701 mutex_unlock(&cc->bio_alloc_lock); 1702 1703 return clone; 1704} 1705 1706static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) 1707{ 1708 struct bio_vec *bv; 1709 struct bvec_iter_all iter_all; 1710 1711 bio_for_each_segment_all(bv, clone, iter_all) { 1712 BUG_ON(!bv->bv_page); 1713 mempool_free(bv->bv_page, &cc->page_pool); 1714 } 1715} 1716 1717static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc, 1718 struct bio *bio, sector_t sector) 1719{ 1720 io->cc = cc; 1721 io->base_bio = bio; 1722 io->sector = sector; 1723 io->error = 0; 1724 io->ctx.r.req = NULL; 1725 io->integrity_metadata = NULL; 1726 io->integrity_metadata_from_pool = false; 1727 io->in_tasklet = false; 1728 atomic_set(&io->io_pending, 0); 1729} 1730 1731static void crypt_inc_pending(struct dm_crypt_io *io) 1732{ 1733 atomic_inc(&io->io_pending); 1734} 1735 1736static void kcryptd_io_bio_endio(struct work_struct *work) 1737{ 1738 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 1739 bio_endio(io->base_bio); 1740} 1741 1742/* 1743 * One of the bios was finished. Check for completion of 1744 * the whole request and correctly clean up the buffer. 1745 */ 1746static void crypt_dec_pending(struct dm_crypt_io *io) 1747{ 1748 struct crypt_config *cc = io->cc; 1749 struct bio *base_bio = io->base_bio; 1750 blk_status_t error = io->error; 1751 1752 if (!atomic_dec_and_test(&io->io_pending)) 1753 return; 1754 1755 if (io->ctx.r.req) 1756 crypt_free_req(cc, io->ctx.r.req, base_bio); 1757 1758 if (unlikely(io->integrity_metadata_from_pool)) 1759 mempool_free(io->integrity_metadata, &io->cc->tag_pool); 1760 else 1761 kfree(io->integrity_metadata); 1762 1763 base_bio->bi_status = error; 1764 1765 /* 1766 * If we are running this function from our tasklet, 1767 * we can't call bio_endio() here, because it will call 1768 * clone_endio() from dm.c, which in turn will 1769 * free the current struct dm_crypt_io structure with 1770 * our tasklet. In this case we need to delay bio_endio() 1771 * execution to after the tasklet is done and dequeued. 1772 */ 1773 if (io->in_tasklet) { 1774 INIT_WORK(&io->work, kcryptd_io_bio_endio); 1775 queue_work(cc->io_queue, &io->work); 1776 return; 1777 } 1778 1779 bio_endio(base_bio); 1780} 1781 1782/* 1783 * kcryptd/kcryptd_io: 1784 * 1785 * Needed because it would be very unwise to do decryption in an 1786 * interrupt context. 1787 * 1788 * kcryptd performs the actual encryption or decryption. 1789 * 1790 * kcryptd_io performs the IO submission. 1791 * 1792 * They must be separated as otherwise the final stages could be 1793 * starved by new requests which can block in the first stages due 1794 * to memory allocation. 1795 * 1796 * The work is done per CPU global for all dm-crypt instances. 1797 * They should not depend on each other and do not block. 1798 */ 1799static void crypt_endio(struct bio *clone) 1800{ 1801 struct dm_crypt_io *io = clone->bi_private; 1802 struct crypt_config *cc = io->cc; 1803 unsigned rw = bio_data_dir(clone); 1804 blk_status_t error; 1805 1806 /* 1807 * free the processed pages 1808 */ 1809 if (rw == WRITE) 1810 crypt_free_buffer_pages(cc, clone); 1811 1812 error = clone->bi_status; 1813 bio_put(clone); 1814 1815 if (rw == READ && !error) { 1816 kcryptd_queue_crypt(io); 1817 return; 1818 } 1819 1820 if (unlikely(error)) 1821 io->error = error; 1822 1823 crypt_dec_pending(io); 1824} 1825 1826static void clone_init(struct dm_crypt_io *io, struct bio *clone) 1827{ 1828 struct crypt_config *cc = io->cc; 1829 1830 clone->bi_private = io; 1831 clone->bi_end_io = crypt_endio; 1832 bio_set_dev(clone, cc->dev->bdev); 1833 clone->bi_opf = io->base_bio->bi_opf; 1834} 1835 1836static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp) 1837{ 1838 struct crypt_config *cc = io->cc; 1839 struct bio *clone; 1840 1841 /* 1842 * We need the original biovec array in order to decrypt 1843 * the whole bio data *afterwards* -- thanks to immutable 1844 * biovecs we don't need to worry about the block layer 1845 * modifying the biovec array; so leverage bio_clone_fast(). 1846 */ 1847 clone = bio_clone_fast(io->base_bio, gfp, &cc->bs); 1848 if (!clone) 1849 return 1; 1850 1851 crypt_inc_pending(io); 1852 1853 clone_init(io, clone); 1854 clone->bi_iter.bi_sector = cc->start + io->sector; 1855 1856 if (dm_crypt_integrity_io_alloc(io, clone)) { 1857 crypt_dec_pending(io); 1858 bio_put(clone); 1859 return 1; 1860 } 1861 1862 submit_bio_noacct(clone); 1863 return 0; 1864} 1865 1866static void kcryptd_io_read_work(struct work_struct *work) 1867{ 1868 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 1869 1870 crypt_inc_pending(io); 1871 if (kcryptd_io_read(io, GFP_NOIO)) 1872 io->error = BLK_STS_RESOURCE; 1873 crypt_dec_pending(io); 1874} 1875 1876static void kcryptd_queue_read(struct dm_crypt_io *io) 1877{ 1878 struct crypt_config *cc = io->cc; 1879 1880 INIT_WORK(&io->work, kcryptd_io_read_work); 1881 queue_work(cc->io_queue, &io->work); 1882} 1883 1884static void kcryptd_io_write(struct dm_crypt_io *io) 1885{ 1886 struct bio *clone = io->ctx.bio_out; 1887 1888 submit_bio_noacct(clone); 1889} 1890 1891#define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node) 1892 1893static int dmcrypt_write(void *data) 1894{ 1895 struct crypt_config *cc = data; 1896 struct dm_crypt_io *io; 1897 1898 while (1) { 1899 struct rb_root write_tree; 1900 struct blk_plug plug; 1901 1902 spin_lock_irq(&cc->write_thread_lock); 1903continue_locked: 1904 1905 if (!RB_EMPTY_ROOT(&cc->write_tree)) 1906 goto pop_from_list; 1907 1908 set_current_state(TASK_INTERRUPTIBLE); 1909 1910 spin_unlock_irq(&cc->write_thread_lock); 1911 1912 if (unlikely(kthread_should_stop())) { 1913 set_current_state(TASK_RUNNING); 1914 break; 1915 } 1916 1917 schedule(); 1918 1919 set_current_state(TASK_RUNNING); 1920 spin_lock_irq(&cc->write_thread_lock); 1921 goto continue_locked; 1922 1923pop_from_list: 1924 write_tree = cc->write_tree; 1925 cc->write_tree = RB_ROOT; 1926 spin_unlock_irq(&cc->write_thread_lock); 1927 1928 BUG_ON(rb_parent(write_tree.rb_node)); 1929 1930 /* 1931 * Note: we cannot walk the tree here with rb_next because 1932 * the structures may be freed when kcryptd_io_write is called. 1933 */ 1934 blk_start_plug(&plug); 1935 do { 1936 io = crypt_io_from_node(rb_first(&write_tree)); 1937 rb_erase(&io->rb_node, &write_tree); 1938 kcryptd_io_write(io); 1939 cond_resched(); 1940 } while (!RB_EMPTY_ROOT(&write_tree)); 1941 blk_finish_plug(&plug); 1942 } 1943 return 0; 1944} 1945 1946static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async) 1947{ 1948 struct bio *clone = io->ctx.bio_out; 1949 struct crypt_config *cc = io->cc; 1950 unsigned long flags; 1951 sector_t sector; 1952 struct rb_node **rbp, *parent; 1953 1954 if (unlikely(io->error)) { 1955 crypt_free_buffer_pages(cc, clone); 1956 bio_put(clone); 1957 crypt_dec_pending(io); 1958 return; 1959 } 1960 1961 /* crypt_convert should have filled the clone bio */ 1962 BUG_ON(io->ctx.iter_out.bi_size); 1963 1964 clone->bi_iter.bi_sector = cc->start + io->sector; 1965 1966 if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) || 1967 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) { 1968 submit_bio_noacct(clone); 1969 return; 1970 } 1971 1972 spin_lock_irqsave(&cc->write_thread_lock, flags); 1973 if (RB_EMPTY_ROOT(&cc->write_tree)) 1974 wake_up_process(cc->write_thread); 1975 rbp = &cc->write_tree.rb_node; 1976 parent = NULL; 1977 sector = io->sector; 1978 while (*rbp) { 1979 parent = *rbp; 1980 if (sector < crypt_io_from_node(parent)->sector) 1981 rbp = &(*rbp)->rb_left; 1982 else 1983 rbp = &(*rbp)->rb_right; 1984 } 1985 rb_link_node(&io->rb_node, parent, rbp); 1986 rb_insert_color(&io->rb_node, &cc->write_tree); 1987 spin_unlock_irqrestore(&cc->write_thread_lock, flags); 1988} 1989 1990static bool kcryptd_crypt_write_inline(struct crypt_config *cc, 1991 struct convert_context *ctx) 1992 1993{ 1994 if (!test_bit(DM_CRYPT_WRITE_INLINE, &cc->flags)) 1995 return false; 1996 1997 /* 1998 * Note: zone append writes (REQ_OP_ZONE_APPEND) do not have ordering 1999 * constraints so they do not need to be issued inline by 2000 * kcryptd_crypt_write_convert(). 2001 */ 2002 switch (bio_op(ctx->bio_in)) { 2003 case REQ_OP_WRITE: 2004 case REQ_OP_WRITE_SAME: 2005 case REQ_OP_WRITE_ZEROES: 2006 return true; 2007 default: 2008 return false; 2009 } 2010} 2011 2012static void kcryptd_crypt_write_continue(struct work_struct *work) 2013{ 2014 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2015 struct crypt_config *cc = io->cc; 2016 struct convert_context *ctx = &io->ctx; 2017 int crypt_finished; 2018 sector_t sector = io->sector; 2019 blk_status_t r; 2020 2021 wait_for_completion(&ctx->restart); 2022 reinit_completion(&ctx->restart); 2023 2024 r = crypt_convert(cc, &io->ctx, true, false); 2025 if (r) 2026 io->error = r; 2027 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2028 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2029 /* Wait for completion signaled by kcryptd_async_done() */ 2030 wait_for_completion(&ctx->restart); 2031 crypt_finished = 1; 2032 } 2033 2034 /* Encryption was already finished, submit io now */ 2035 if (crypt_finished) { 2036 kcryptd_crypt_write_io_submit(io, 0); 2037 io->sector = sector; 2038 } 2039 2040 crypt_dec_pending(io); 2041} 2042 2043static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) 2044{ 2045 struct crypt_config *cc = io->cc; 2046 struct convert_context *ctx = &io->ctx; 2047 struct bio *clone; 2048 int crypt_finished; 2049 sector_t sector = io->sector; 2050 blk_status_t r; 2051 2052 /* 2053 * Prevent io from disappearing until this function completes. 2054 */ 2055 crypt_inc_pending(io); 2056 crypt_convert_init(cc, ctx, NULL, io->base_bio, sector); 2057 2058 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size); 2059 if (unlikely(!clone)) { 2060 io->error = BLK_STS_IOERR; 2061 goto dec; 2062 } 2063 2064 io->ctx.bio_out = clone; 2065 io->ctx.iter_out = clone->bi_iter; 2066 2067 sector += bio_sectors(clone); 2068 2069 crypt_inc_pending(io); 2070 r = crypt_convert(cc, ctx, 2071 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags), true); 2072 /* 2073 * Crypto API backlogged the request, because its queue was full 2074 * and we're in softirq context, so continue from a workqueue 2075 * (TODO: is it actually possible to be in softirq in the write path?) 2076 */ 2077 if (r == BLK_STS_DEV_RESOURCE) { 2078 INIT_WORK(&io->work, kcryptd_crypt_write_continue); 2079 queue_work(cc->crypt_queue, &io->work); 2080 return; 2081 } 2082 if (r) 2083 io->error = r; 2084 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2085 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2086 /* Wait for completion signaled by kcryptd_async_done() */ 2087 wait_for_completion(&ctx->restart); 2088 crypt_finished = 1; 2089 } 2090 2091 /* Encryption was already finished, submit io now */ 2092 if (crypt_finished) { 2093 kcryptd_crypt_write_io_submit(io, 0); 2094 io->sector = sector; 2095 } 2096 2097dec: 2098 crypt_dec_pending(io); 2099} 2100 2101static void kcryptd_crypt_read_done(struct dm_crypt_io *io) 2102{ 2103 crypt_dec_pending(io); 2104} 2105 2106static void kcryptd_crypt_read_continue(struct work_struct *work) 2107{ 2108 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2109 struct crypt_config *cc = io->cc; 2110 blk_status_t r; 2111 2112 wait_for_completion(&io->ctx.restart); 2113 reinit_completion(&io->ctx.restart); 2114 2115 r = crypt_convert(cc, &io->ctx, true, false); 2116 if (r) 2117 io->error = r; 2118 2119 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2120 kcryptd_crypt_read_done(io); 2121 2122 crypt_dec_pending(io); 2123} 2124 2125static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) 2126{ 2127 struct crypt_config *cc = io->cc; 2128 blk_status_t r; 2129 2130 crypt_inc_pending(io); 2131 2132 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, 2133 io->sector); 2134 2135 r = crypt_convert(cc, &io->ctx, 2136 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true); 2137 /* 2138 * Crypto API backlogged the request, because its queue was full 2139 * and we're in softirq context, so continue from a workqueue 2140 */ 2141 if (r == BLK_STS_DEV_RESOURCE) { 2142 INIT_WORK(&io->work, kcryptd_crypt_read_continue); 2143 queue_work(cc->crypt_queue, &io->work); 2144 return; 2145 } 2146 if (r) 2147 io->error = r; 2148 2149 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2150 kcryptd_crypt_read_done(io); 2151 2152 crypt_dec_pending(io); 2153} 2154 2155static void kcryptd_async_done(struct crypto_async_request *async_req, 2156 int error) 2157{ 2158 struct dm_crypt_request *dmreq = async_req->data; 2159 struct convert_context *ctx = dmreq->ctx; 2160 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 2161 struct crypt_config *cc = io->cc; 2162 2163 /* 2164 * A request from crypto driver backlog is going to be processed now, 2165 * finish the completion and continue in crypt_convert(). 2166 * (Callback will be called for the second time for this request.) 2167 */ 2168 if (error == -EINPROGRESS) { 2169 complete(&ctx->restart); 2170 return; 2171 } 2172 2173 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post) 2174 error = cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq); 2175 2176 if (error == -EBADMSG) { 2177 char b[BDEVNAME_SIZE]; 2178 DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu", bio_devname(ctx->bio_in, b), 2179 (unsigned long long)le64_to_cpu(*org_sector_of_dmreq(cc, dmreq))); 2180 io->error = BLK_STS_PROTECTION; 2181 } else if (error < 0) 2182 io->error = BLK_STS_IOERR; 2183 2184 crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio); 2185 2186 if (!atomic_dec_and_test(&ctx->cc_pending)) 2187 return; 2188 2189 /* 2190 * The request is fully completed: for inline writes, let 2191 * kcryptd_crypt_write_convert() do the IO submission. 2192 */ 2193 if (bio_data_dir(io->base_bio) == READ) { 2194 kcryptd_crypt_read_done(io); 2195 return; 2196 } 2197 2198 if (kcryptd_crypt_write_inline(cc, ctx)) { 2199 complete(&ctx->restart); 2200 return; 2201 } 2202 2203 kcryptd_crypt_write_io_submit(io, 1); 2204} 2205 2206static void kcryptd_crypt(struct work_struct *work) 2207{ 2208 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2209 2210 if (bio_data_dir(io->base_bio) == READ) 2211 kcryptd_crypt_read_convert(io); 2212 else 2213 kcryptd_crypt_write_convert(io); 2214} 2215 2216static void kcryptd_crypt_tasklet(unsigned long work) 2217{ 2218 kcryptd_crypt((struct work_struct *)work); 2219} 2220 2221static void kcryptd_queue_crypt(struct dm_crypt_io *io) 2222{ 2223 struct crypt_config *cc = io->cc; 2224 2225 if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) || 2226 (bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) { 2227 /* 2228 * in_irq(): Crypto API's skcipher_walk_first() refuses to work in hard IRQ context. 2229 * irqs_disabled(): the kernel may run some IO completion from the idle thread, but 2230 * it is being executed with irqs disabled. 2231 */ 2232 if (in_irq() || irqs_disabled()) { 2233 io->in_tasklet = true; 2234 tasklet_init(&io->tasklet, kcryptd_crypt_tasklet, (unsigned long)&io->work); 2235 tasklet_schedule(&io->tasklet); 2236 return; 2237 } 2238 2239 kcryptd_crypt(&io->work); 2240 return; 2241 } 2242 2243 INIT_WORK(&io->work, kcryptd_crypt); 2244 queue_work(cc->crypt_queue, &io->work); 2245} 2246 2247static void crypt_free_tfms_aead(struct crypt_config *cc) 2248{ 2249 if (!cc->cipher_tfm.tfms_aead) 2250 return; 2251 2252 if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2253 crypto_free_aead(cc->cipher_tfm.tfms_aead[0]); 2254 cc->cipher_tfm.tfms_aead[0] = NULL; 2255 } 2256 2257 kfree(cc->cipher_tfm.tfms_aead); 2258 cc->cipher_tfm.tfms_aead = NULL; 2259} 2260 2261static void crypt_free_tfms_skcipher(struct crypt_config *cc) 2262{ 2263 unsigned i; 2264 2265 if (!cc->cipher_tfm.tfms) 2266 return; 2267 2268 for (i = 0; i < cc->tfms_count; i++) 2269 if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) { 2270 crypto_free_skcipher(cc->cipher_tfm.tfms[i]); 2271 cc->cipher_tfm.tfms[i] = NULL; 2272 } 2273 2274 kfree(cc->cipher_tfm.tfms); 2275 cc->cipher_tfm.tfms = NULL; 2276} 2277 2278static void crypt_free_tfms(struct crypt_config *cc) 2279{ 2280 if (crypt_integrity_aead(cc)) 2281 crypt_free_tfms_aead(cc); 2282 else 2283 crypt_free_tfms_skcipher(cc); 2284} 2285 2286static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode) 2287{ 2288 unsigned i; 2289 int err; 2290 2291 cc->cipher_tfm.tfms = kcalloc(cc->tfms_count, 2292 sizeof(struct crypto_skcipher *), 2293 GFP_KERNEL); 2294 if (!cc->cipher_tfm.tfms) 2295 return -ENOMEM; 2296 2297 for (i = 0; i < cc->tfms_count; i++) { 2298 cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0, 2299 CRYPTO_ALG_ALLOCATES_MEMORY); 2300 if (IS_ERR(cc->cipher_tfm.tfms[i])) { 2301 err = PTR_ERR(cc->cipher_tfm.tfms[i]); 2302 crypt_free_tfms(cc); 2303 return err; 2304 } 2305 } 2306 2307 /* 2308 * dm-crypt performance can vary greatly depending on which crypto 2309 * algorithm implementation is used. Help people debug performance 2310 * problems by logging the ->cra_driver_name. 2311 */ 2312 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2313 crypto_skcipher_alg(any_tfm(cc))->base.cra_driver_name); 2314 return 0; 2315} 2316 2317static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode) 2318{ 2319 int err; 2320 2321 cc->cipher_tfm.tfms = kmalloc(sizeof(struct crypto_aead *), GFP_KERNEL); 2322 if (!cc->cipher_tfm.tfms) 2323 return -ENOMEM; 2324 2325 cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0, 2326 CRYPTO_ALG_ALLOCATES_MEMORY); 2327 if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2328 err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]); 2329 crypt_free_tfms(cc); 2330 return err; 2331 } 2332 2333 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2334 crypto_aead_alg(any_tfm_aead(cc))->base.cra_driver_name); 2335 return 0; 2336} 2337 2338static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode) 2339{ 2340 if (crypt_integrity_aead(cc)) 2341 return crypt_alloc_tfms_aead(cc, ciphermode); 2342 else 2343 return crypt_alloc_tfms_skcipher(cc, ciphermode); 2344} 2345 2346static unsigned crypt_subkey_size(struct crypt_config *cc) 2347{ 2348 return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count); 2349} 2350 2351static unsigned crypt_authenckey_size(struct crypt_config *cc) 2352{ 2353 return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param)); 2354} 2355 2356/* 2357 * If AEAD is composed like authenc(hmac(sha256),xts(aes)), 2358 * the key must be for some reason in special format. 2359 * This funcion converts cc->key to this special format. 2360 */ 2361static void crypt_copy_authenckey(char *p, const void *key, 2362 unsigned enckeylen, unsigned authkeylen) 2363{ 2364 struct crypto_authenc_key_param *param; 2365 struct rtattr *rta; 2366 2367 rta = (struct rtattr *)p; 2368 param = RTA_DATA(rta); 2369 param->enckeylen = cpu_to_be32(enckeylen); 2370 rta->rta_len = RTA_LENGTH(sizeof(*param)); 2371 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; 2372 p += RTA_SPACE(sizeof(*param)); 2373 memcpy(p, key + enckeylen, authkeylen); 2374 p += authkeylen; 2375 memcpy(p, key, enckeylen); 2376} 2377 2378static int crypt_setkey(struct crypt_config *cc) 2379{ 2380 unsigned subkey_size; 2381 int err = 0, i, r; 2382 2383 /* Ignore extra keys (which are used for IV etc) */ 2384 subkey_size = crypt_subkey_size(cc); 2385 2386 if (crypt_integrity_hmac(cc)) { 2387 if (subkey_size < cc->key_mac_size) 2388 return -EINVAL; 2389 2390 crypt_copy_authenckey(cc->authenc_key, cc->key, 2391 subkey_size - cc->key_mac_size, 2392 cc->key_mac_size); 2393 } 2394 2395 for (i = 0; i < cc->tfms_count; i++) { 2396 if (crypt_integrity_hmac(cc)) 2397 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2398 cc->authenc_key, crypt_authenckey_size(cc)); 2399 else if (crypt_integrity_aead(cc)) 2400 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2401 cc->key + (i * subkey_size), 2402 subkey_size); 2403 else 2404 r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i], 2405 cc->key + (i * subkey_size), 2406 subkey_size); 2407 if (r) 2408 err = r; 2409 } 2410 2411 if (crypt_integrity_hmac(cc)) 2412 memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc)); 2413 2414 return err; 2415} 2416 2417#ifdef CONFIG_KEYS 2418 2419static bool contains_whitespace(const char *str) 2420{ 2421 while (*str) 2422 if (isspace(*str++)) 2423 return true; 2424 return false; 2425} 2426 2427static int set_key_user(struct crypt_config *cc, struct key *key) 2428{ 2429 const struct user_key_payload *ukp; 2430 2431 ukp = user_key_payload_locked(key); 2432 if (!ukp) 2433 return -EKEYREVOKED; 2434 2435 if (cc->key_size != ukp->datalen) 2436 return -EINVAL; 2437 2438 memcpy(cc->key, ukp->data, cc->key_size); 2439 2440 return 0; 2441} 2442 2443#if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE) 2444static int set_key_encrypted(struct crypt_config *cc, struct key *key) 2445{ 2446 const struct encrypted_key_payload *ekp; 2447 2448 ekp = key->payload.data[0]; 2449 if (!ekp) 2450 return -EKEYREVOKED; 2451 2452 if (cc->key_size != ekp->decrypted_datalen) 2453 return -EINVAL; 2454 2455 memcpy(cc->key, ekp->decrypted_data, cc->key_size); 2456 2457 return 0; 2458} 2459#endif /* CONFIG_ENCRYPTED_KEYS */ 2460 2461static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2462{ 2463 char *new_key_string, *key_desc; 2464 int ret; 2465 struct key_type *type; 2466 struct key *key; 2467 int (*set_key)(struct crypt_config *cc, struct key *key); 2468 2469 /* 2470 * Reject key_string with whitespace. dm core currently lacks code for 2471 * proper whitespace escaping in arguments on DM_TABLE_STATUS path. 2472 */ 2473 if (contains_whitespace(key_string)) { 2474 DMERR("whitespace chars not allowed in key string"); 2475 return -EINVAL; 2476 } 2477 2478 /* look for next ':' separating key_type from key_description */ 2479 key_desc = strpbrk(key_string, ":"); 2480 if (!key_desc || key_desc == key_string || !strlen(key_desc + 1)) 2481 return -EINVAL; 2482 2483 if (!strncmp(key_string, "logon:", key_desc - key_string + 1)) { 2484 type = &key_type_logon; 2485 set_key = set_key_user; 2486 } else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) { 2487 type = &key_type_user; 2488 set_key = set_key_user; 2489#if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE) 2490 } else if (!strncmp(key_string, "encrypted:", key_desc - key_string + 1)) { 2491 type = &key_type_encrypted; 2492 set_key = set_key_encrypted; 2493#endif 2494 } else { 2495 return -EINVAL; 2496 } 2497 2498 new_key_string = kstrdup(key_string, GFP_KERNEL); 2499 if (!new_key_string) 2500 return -ENOMEM; 2501 2502 key = request_key(type, key_desc + 1, NULL); 2503 if (IS_ERR(key)) { 2504 kfree_sensitive(new_key_string); 2505 return PTR_ERR(key); 2506 } 2507 2508 down_read(&key->sem); 2509 2510 ret = set_key(cc, key); 2511 if (ret < 0) { 2512 up_read(&key->sem); 2513 key_put(key); 2514 kfree_sensitive(new_key_string); 2515 return ret; 2516 } 2517 2518 up_read(&key->sem); 2519 key_put(key); 2520 2521 /* clear the flag since following operations may invalidate previously valid key */ 2522 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2523 2524 ret = crypt_setkey(cc); 2525 2526 if (!ret) { 2527 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2528 kfree_sensitive(cc->key_string); 2529 cc->key_string = new_key_string; 2530 } else 2531 kfree_sensitive(new_key_string); 2532 2533 return ret; 2534} 2535 2536static int get_key_size(char **key_string) 2537{ 2538 char *colon, dummy; 2539 int ret; 2540 2541 if (*key_string[0] != ':') 2542 return strlen(*key_string) >> 1; 2543 2544 /* look for next ':' in key string */ 2545 colon = strpbrk(*key_string + 1, ":"); 2546 if (!colon) 2547 return -EINVAL; 2548 2549 if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':') 2550 return -EINVAL; 2551 2552 *key_string = colon; 2553 2554 /* remaining key string should be :<logon|user>:<key_desc> */ 2555 2556 return ret; 2557} 2558 2559#else 2560 2561static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2562{ 2563 return -EINVAL; 2564} 2565 2566static int get_key_size(char **key_string) 2567{ 2568 return (*key_string[0] == ':') ? -EINVAL : (int)(strlen(*key_string) >> 1); 2569} 2570 2571#endif /* CONFIG_KEYS */ 2572 2573static int crypt_set_key(struct crypt_config *cc, char *key) 2574{ 2575 int r = -EINVAL; 2576 int key_string_len = strlen(key); 2577 2578 /* Hyphen (which gives a key_size of zero) means there is no key. */ 2579 if (!cc->key_size && strcmp(key, "-")) 2580 goto out; 2581 2582 /* ':' means the key is in kernel keyring, short-circuit normal key processing */ 2583 if (key[0] == ':') { 2584 r = crypt_set_keyring_key(cc, key + 1); 2585 goto out; 2586 } 2587 2588 /* clear the flag since following operations may invalidate previously valid key */ 2589 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2590 2591 /* wipe references to any kernel keyring key */ 2592 kfree_sensitive(cc->key_string); 2593 cc->key_string = NULL; 2594 2595 /* Decode key from its hex representation. */ 2596 if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0) 2597 goto out; 2598 2599 r = crypt_setkey(cc); 2600 if (!r) 2601 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2602 2603out: 2604 /* Hex key string not needed after here, so wipe it. */ 2605 memset(key, '0', key_string_len); 2606 2607 return r; 2608} 2609 2610static int crypt_wipe_key(struct crypt_config *cc) 2611{ 2612 int r; 2613 2614 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2615 get_random_bytes(&cc->key, cc->key_size); 2616 2617 /* Wipe IV private keys */ 2618 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) { 2619 r = cc->iv_gen_ops->wipe(cc); 2620 if (r) 2621 return r; 2622 } 2623 2624 kfree_sensitive(cc->key_string); 2625 cc->key_string = NULL; 2626 r = crypt_setkey(cc); 2627 memset(&cc->key, 0, cc->key_size * sizeof(u8)); 2628 2629 return r; 2630} 2631 2632static void crypt_calculate_pages_per_client(void) 2633{ 2634 unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100; 2635 2636 if (!dm_crypt_clients_n) 2637 return; 2638 2639 pages /= dm_crypt_clients_n; 2640 if (pages < DM_CRYPT_MIN_PAGES_PER_CLIENT) 2641 pages = DM_CRYPT_MIN_PAGES_PER_CLIENT; 2642 dm_crypt_pages_per_client = pages; 2643} 2644 2645static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data) 2646{ 2647 struct crypt_config *cc = pool_data; 2648 struct page *page; 2649 2650 /* 2651 * Note, percpu_counter_read_positive() may over (and under) estimate 2652 * the current usage by at most (batch - 1) * num_online_cpus() pages, 2653 * but avoids potential spinlock contention of an exact result. 2654 */ 2655 if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) >= dm_crypt_pages_per_client) && 2656 likely(gfp_mask & __GFP_NORETRY)) 2657 return NULL; 2658 2659 page = alloc_page(gfp_mask); 2660 if (likely(page != NULL)) 2661 percpu_counter_add(&cc->n_allocated_pages, 1); 2662 2663 return page; 2664} 2665 2666static void crypt_page_free(void *page, void *pool_data) 2667{ 2668 struct crypt_config *cc = pool_data; 2669 2670 __free_page(page); 2671 percpu_counter_sub(&cc->n_allocated_pages, 1); 2672} 2673 2674static void crypt_dtr(struct dm_target *ti) 2675{ 2676 struct crypt_config *cc = ti->private; 2677 2678 ti->private = NULL; 2679 2680 if (!cc) 2681 return; 2682 2683 if (cc->write_thread) 2684 kthread_stop(cc->write_thread); 2685 2686 if (cc->io_queue) 2687 destroy_workqueue(cc->io_queue); 2688 if (cc->crypt_queue) 2689 destroy_workqueue(cc->crypt_queue); 2690 2691 crypt_free_tfms(cc); 2692 2693 bioset_exit(&cc->bs); 2694 2695 mempool_exit(&cc->page_pool); 2696 mempool_exit(&cc->req_pool); 2697 mempool_exit(&cc->tag_pool); 2698 2699 WARN_ON(percpu_counter_sum(&cc->n_allocated_pages) != 0); 2700 percpu_counter_destroy(&cc->n_allocated_pages); 2701 2702 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) 2703 cc->iv_gen_ops->dtr(cc); 2704 2705 if (cc->dev) 2706 dm_put_device(ti, cc->dev); 2707 2708 kfree_sensitive(cc->cipher_string); 2709 kfree_sensitive(cc->key_string); 2710 kfree_sensitive(cc->cipher_auth); 2711 kfree_sensitive(cc->authenc_key); 2712 2713 mutex_destroy(&cc->bio_alloc_lock); 2714 2715 /* Must zero key material before freeing */ 2716 kfree_sensitive(cc); 2717 2718 spin_lock(&dm_crypt_clients_lock); 2719 WARN_ON(!dm_crypt_clients_n); 2720 dm_crypt_clients_n--; 2721 crypt_calculate_pages_per_client(); 2722 spin_unlock(&dm_crypt_clients_lock); 2723} 2724 2725static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode) 2726{ 2727 struct crypt_config *cc = ti->private; 2728 2729 if (crypt_integrity_aead(cc)) 2730 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2731 else 2732 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2733 2734 if (cc->iv_size) 2735 /* at least a 64 bit sector number should fit in our buffer */ 2736 cc->iv_size = max(cc->iv_size, 2737 (unsigned int)(sizeof(u64) / sizeof(u8))); 2738 else if (ivmode) { 2739 DMWARN("Selected cipher does not support IVs"); 2740 ivmode = NULL; 2741 } 2742 2743 /* Choose ivmode, see comments at iv code. */ 2744 if (ivmode == NULL) 2745 cc->iv_gen_ops = NULL; 2746 else if (strcmp(ivmode, "plain") == 0) 2747 cc->iv_gen_ops = &crypt_iv_plain_ops; 2748 else if (strcmp(ivmode, "plain64") == 0) 2749 cc->iv_gen_ops = &crypt_iv_plain64_ops; 2750 else if (strcmp(ivmode, "plain64be") == 0) 2751 cc->iv_gen_ops = &crypt_iv_plain64be_ops; 2752 else if (strcmp(ivmode, "essiv") == 0) 2753 cc->iv_gen_ops = &crypt_iv_essiv_ops; 2754 else if (strcmp(ivmode, "benbi") == 0) 2755 cc->iv_gen_ops = &crypt_iv_benbi_ops; 2756 else if (strcmp(ivmode, "null") == 0) 2757 cc->iv_gen_ops = &crypt_iv_null_ops; 2758 else if (strcmp(ivmode, "eboiv") == 0) 2759 cc->iv_gen_ops = &crypt_iv_eboiv_ops; 2760 else if (strcmp(ivmode, "elephant") == 0) { 2761 cc->iv_gen_ops = &crypt_iv_elephant_ops; 2762 cc->key_parts = 2; 2763 cc->key_extra_size = cc->key_size / 2; 2764 if (cc->key_extra_size > ELEPHANT_MAX_KEY_SIZE) 2765 return -EINVAL; 2766 set_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags); 2767 } else if (strcmp(ivmode, "lmk") == 0) { 2768 cc->iv_gen_ops = &crypt_iv_lmk_ops; 2769 /* 2770 * Version 2 and 3 is recognised according 2771 * to length of provided multi-key string. 2772 * If present (version 3), last key is used as IV seed. 2773 * All keys (including IV seed) are always the same size. 2774 */ 2775 if (cc->key_size % cc->key_parts) { 2776 cc->key_parts++; 2777 cc->key_extra_size = cc->key_size / cc->key_parts; 2778 } 2779 } else if (strcmp(ivmode, "tcw") == 0) { 2780 cc->iv_gen_ops = &crypt_iv_tcw_ops; 2781 cc->key_parts += 2; /* IV + whitening */ 2782 cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE; 2783 } else if (strcmp(ivmode, "random") == 0) { 2784 cc->iv_gen_ops = &crypt_iv_random_ops; 2785 /* Need storage space in integrity fields. */ 2786 cc->integrity_iv_size = cc->iv_size; 2787 } else { 2788 ti->error = "Invalid IV mode"; 2789 return -EINVAL; 2790 } 2791 2792 return 0; 2793} 2794 2795/* 2796 * Workaround to parse HMAC algorithm from AEAD crypto API spec. 2797 * The HMAC is needed to calculate tag size (HMAC digest size). 2798 * This should be probably done by crypto-api calls (once available...) 2799 */ 2800static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api) 2801{ 2802 char *start, *end, *mac_alg = NULL; 2803 struct crypto_ahash *mac; 2804 2805 if (!strstarts(cipher_api, "authenc(")) 2806 return 0; 2807 2808 start = strchr(cipher_api, '('); 2809 end = strchr(cipher_api, ','); 2810 if (!start || !end || ++start > end) 2811 return -EINVAL; 2812 2813 mac_alg = kzalloc(end - start + 1, GFP_KERNEL); 2814 if (!mac_alg) 2815 return -ENOMEM; 2816 strncpy(mac_alg, start, end - start); 2817 2818 mac = crypto_alloc_ahash(mac_alg, 0, CRYPTO_ALG_ALLOCATES_MEMORY); 2819 kfree(mac_alg); 2820 2821 if (IS_ERR(mac)) 2822 return PTR_ERR(mac); 2823 2824 cc->key_mac_size = crypto_ahash_digestsize(mac); 2825 crypto_free_ahash(mac); 2826 2827 cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL); 2828 if (!cc->authenc_key) 2829 return -ENOMEM; 2830 2831 return 0; 2832} 2833 2834static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key, 2835 char **ivmode, char **ivopts) 2836{ 2837 struct crypt_config *cc = ti->private; 2838 char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME]; 2839 int ret = -EINVAL; 2840 2841 cc->tfms_count = 1; 2842 2843 /* 2844 * New format (capi: prefix) 2845 * capi:cipher_api_spec-iv:ivopts 2846 */ 2847 tmp = &cipher_in[strlen("capi:")]; 2848 2849 /* Separate IV options if present, it can contain another '-' in hash name */ 2850 *ivopts = strrchr(tmp, ':'); 2851 if (*ivopts) { 2852 **ivopts = '\0'; 2853 (*ivopts)++; 2854 } 2855 /* Parse IV mode */ 2856 *ivmode = strrchr(tmp, '-'); 2857 if (*ivmode) { 2858 **ivmode = '\0'; 2859 (*ivmode)++; 2860 } 2861 /* The rest is crypto API spec */ 2862 cipher_api = tmp; 2863 2864 /* Alloc AEAD, can be used only in new format. */ 2865 if (crypt_integrity_aead(cc)) { 2866 ret = crypt_ctr_auth_cipher(cc, cipher_api); 2867 if (ret < 0) { 2868 ti->error = "Invalid AEAD cipher spec"; 2869 return -ENOMEM; 2870 } 2871 } 2872 2873 if (*ivmode && !strcmp(*ivmode, "lmk")) 2874 cc->tfms_count = 64; 2875 2876 if (*ivmode && !strcmp(*ivmode, "essiv")) { 2877 if (!*ivopts) { 2878 ti->error = "Digest algorithm missing for ESSIV mode"; 2879 return -EINVAL; 2880 } 2881 ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)", 2882 cipher_api, *ivopts); 2883 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 2884 ti->error = "Cannot allocate cipher string"; 2885 return -ENOMEM; 2886 } 2887 cipher_api = buf; 2888 } 2889 2890 cc->key_parts = cc->tfms_count; 2891 2892 /* Allocate cipher */ 2893 ret = crypt_alloc_tfms(cc, cipher_api); 2894 if (ret < 0) { 2895 ti->error = "Error allocating crypto tfm"; 2896 return ret; 2897 } 2898 2899 if (crypt_integrity_aead(cc)) 2900 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2901 else 2902 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2903 2904 return 0; 2905} 2906 2907static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key, 2908 char **ivmode, char **ivopts) 2909{ 2910 struct crypt_config *cc = ti->private; 2911 char *tmp, *cipher, *chainmode, *keycount; 2912 char *cipher_api = NULL; 2913 int ret = -EINVAL; 2914 char dummy; 2915 2916 if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) { 2917 ti->error = "Bad cipher specification"; 2918 return -EINVAL; 2919 } 2920 2921 /* 2922 * Legacy dm-crypt cipher specification 2923 * cipher[:keycount]-mode-iv:ivopts 2924 */ 2925 tmp = cipher_in; 2926 keycount = strsep(&tmp, "-"); 2927 cipher = strsep(&keycount, ":"); 2928 2929 if (!keycount) 2930 cc->tfms_count = 1; 2931 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 || 2932 !is_power_of_2(cc->tfms_count)) { 2933 ti->error = "Bad cipher key count specification"; 2934 return -EINVAL; 2935 } 2936 cc->key_parts = cc->tfms_count; 2937 2938 chainmode = strsep(&tmp, "-"); 2939 *ivmode = strsep(&tmp, ":"); 2940 *ivopts = tmp; 2941 2942 /* 2943 * For compatibility with the original dm-crypt mapping format, if 2944 * only the cipher name is supplied, use cbc-plain. 2945 */ 2946 if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) { 2947 chainmode = "cbc"; 2948 *ivmode = "plain"; 2949 } 2950 2951 if (strcmp(chainmode, "ecb") && !*ivmode) { 2952 ti->error = "IV mechanism required"; 2953 return -EINVAL; 2954 } 2955 2956 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL); 2957 if (!cipher_api) 2958 goto bad_mem; 2959 2960 if (*ivmode && !strcmp(*ivmode, "essiv")) { 2961 if (!*ivopts) { 2962 ti->error = "Digest algorithm missing for ESSIV mode"; 2963 kfree(cipher_api); 2964 return -EINVAL; 2965 } 2966 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 2967 "essiv(%s(%s),%s)", chainmode, cipher, *ivopts); 2968 } else { 2969 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 2970 "%s(%s)", chainmode, cipher); 2971 } 2972 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 2973 kfree(cipher_api); 2974 goto bad_mem; 2975 } 2976 2977 /* Allocate cipher */ 2978 ret = crypt_alloc_tfms(cc, cipher_api); 2979 if (ret < 0) { 2980 ti->error = "Error allocating crypto tfm"; 2981 kfree(cipher_api); 2982 return ret; 2983 } 2984 kfree(cipher_api); 2985 2986 return 0; 2987bad_mem: 2988 ti->error = "Cannot allocate cipher strings"; 2989 return -ENOMEM; 2990} 2991 2992static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key) 2993{ 2994 struct crypt_config *cc = ti->private; 2995 char *ivmode = NULL, *ivopts = NULL; 2996 int ret; 2997 2998 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL); 2999 if (!cc->cipher_string) { 3000 ti->error = "Cannot allocate cipher strings"; 3001 return -ENOMEM; 3002 } 3003 3004 if (strstarts(cipher_in, "capi:")) 3005 ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts); 3006 else 3007 ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts); 3008 if (ret) 3009 return ret; 3010 3011 /* Initialize IV */ 3012 ret = crypt_ctr_ivmode(ti, ivmode); 3013 if (ret < 0) 3014 return ret; 3015 3016 /* Initialize and set key */ 3017 ret = crypt_set_key(cc, key); 3018 if (ret < 0) { 3019 ti->error = "Error decoding and setting key"; 3020 return ret; 3021 } 3022 3023 /* Allocate IV */ 3024 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) { 3025 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts); 3026 if (ret < 0) { 3027 ti->error = "Error creating IV"; 3028 return ret; 3029 } 3030 } 3031 3032 /* Initialize IV (set keys for ESSIV etc) */ 3033 if (cc->iv_gen_ops && cc->iv_gen_ops->init) { 3034 ret = cc->iv_gen_ops->init(cc); 3035 if (ret < 0) { 3036 ti->error = "Error initialising IV"; 3037 return ret; 3038 } 3039 } 3040 3041 /* wipe the kernel key payload copy */ 3042 if (cc->key_string) 3043 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3044 3045 return ret; 3046} 3047 3048static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv) 3049{ 3050 struct crypt_config *cc = ti->private; 3051 struct dm_arg_set as; 3052 static const struct dm_arg _args[] = { 3053 {0, 8, "Invalid number of feature args"}, 3054 }; 3055 unsigned int opt_params, val; 3056 const char *opt_string, *sval; 3057 char dummy; 3058 int ret; 3059 3060 /* Optional parameters */ 3061 as.argc = argc; 3062 as.argv = argv; 3063 3064 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error); 3065 if (ret) 3066 return ret; 3067 3068 while (opt_params--) { 3069 opt_string = dm_shift_arg(&as); 3070 if (!opt_string) { 3071 ti->error = "Not enough feature arguments"; 3072 return -EINVAL; 3073 } 3074 3075 if (!strcasecmp(opt_string, "allow_discards")) 3076 ti->num_discard_bios = 1; 3077 3078 else if (!strcasecmp(opt_string, "same_cpu_crypt")) 3079 set_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3080 3081 else if (!strcasecmp(opt_string, "submit_from_crypt_cpus")) 3082 set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3083 else if (!strcasecmp(opt_string, "no_read_workqueue")) 3084 set_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3085 else if (!strcasecmp(opt_string, "no_write_workqueue")) 3086 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3087 else if (sscanf(opt_string, "integrity:%u:", &val) == 1) { 3088 if (val == 0 || val > MAX_TAG_SIZE) { 3089 ti->error = "Invalid integrity arguments"; 3090 return -EINVAL; 3091 } 3092 cc->on_disk_tag_size = val; 3093 sval = strchr(opt_string + strlen("integrity:"), ':') + 1; 3094 if (!strcasecmp(sval, "aead")) { 3095 set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 3096 } else if (strcasecmp(sval, "none")) { 3097 ti->error = "Unknown integrity profile"; 3098 return -EINVAL; 3099 } 3100 3101 cc->cipher_auth = kstrdup(sval, GFP_KERNEL); 3102 if (!cc->cipher_auth) 3103 return -ENOMEM; 3104 } else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) { 3105 if (cc->sector_size < (1 << SECTOR_SHIFT) || 3106 cc->sector_size > 4096 || 3107 (cc->sector_size & (cc->sector_size - 1))) { 3108 ti->error = "Invalid feature value for sector_size"; 3109 return -EINVAL; 3110 } 3111 if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) { 3112 ti->error = "Device size is not multiple of sector_size feature"; 3113 return -EINVAL; 3114 } 3115 cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT; 3116 } else if (!strcasecmp(opt_string, "iv_large_sectors")) 3117 set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3118 else { 3119 ti->error = "Invalid feature arguments"; 3120 return -EINVAL; 3121 } 3122 } 3123 3124 return 0; 3125} 3126 3127#ifdef CONFIG_BLK_DEV_ZONED 3128 3129static int crypt_report_zones(struct dm_target *ti, 3130 struct dm_report_zones_args *args, unsigned int nr_zones) 3131{ 3132 struct crypt_config *cc = ti->private; 3133 sector_t sector = cc->start + dm_target_offset(ti, args->next_sector); 3134 3135 args->start = cc->start; 3136 return blkdev_report_zones(cc->dev->bdev, sector, nr_zones, 3137 dm_report_zones_cb, args); 3138} 3139 3140#endif 3141 3142/* 3143 * Construct an encryption mapping: 3144 * <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start> 3145 */ 3146static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) 3147{ 3148 struct crypt_config *cc; 3149 const char *devname = dm_table_device_name(ti->table); 3150 int key_size; 3151 unsigned int align_mask; 3152 unsigned long long tmpll; 3153 int ret; 3154 size_t iv_size_padding, additional_req_size; 3155 char dummy; 3156 3157 if (argc < 5) { 3158 ti->error = "Not enough arguments"; 3159 return -EINVAL; 3160 } 3161 3162 key_size = get_key_size(&argv[1]); 3163 if (key_size < 0) { 3164 ti->error = "Cannot parse key size"; 3165 return -EINVAL; 3166 } 3167 3168 cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL); 3169 if (!cc) { 3170 ti->error = "Cannot allocate encryption context"; 3171 return -ENOMEM; 3172 } 3173 cc->key_size = key_size; 3174 cc->sector_size = (1 << SECTOR_SHIFT); 3175 cc->sector_shift = 0; 3176 3177 ti->private = cc; 3178 3179 spin_lock(&dm_crypt_clients_lock); 3180 dm_crypt_clients_n++; 3181 crypt_calculate_pages_per_client(); 3182 spin_unlock(&dm_crypt_clients_lock); 3183 3184 ret = percpu_counter_init(&cc->n_allocated_pages, 0, GFP_KERNEL); 3185 if (ret < 0) 3186 goto bad; 3187 3188 /* Optional parameters need to be read before cipher constructor */ 3189 if (argc > 5) { 3190 ret = crypt_ctr_optional(ti, argc - 5, &argv[5]); 3191 if (ret) 3192 goto bad; 3193 } 3194 3195 ret = crypt_ctr_cipher(ti, argv[0], argv[1]); 3196 if (ret < 0) 3197 goto bad; 3198 3199 if (crypt_integrity_aead(cc)) { 3200 cc->dmreq_start = sizeof(struct aead_request); 3201 cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc)); 3202 align_mask = crypto_aead_alignmask(any_tfm_aead(cc)); 3203 } else { 3204 cc->dmreq_start = sizeof(struct skcipher_request); 3205 cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc)); 3206 align_mask = crypto_skcipher_alignmask(any_tfm(cc)); 3207 } 3208 cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request)); 3209 3210 if (align_mask < CRYPTO_MINALIGN) { 3211 /* Allocate the padding exactly */ 3212 iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request)) 3213 & align_mask; 3214 } else { 3215 /* 3216 * If the cipher requires greater alignment than kmalloc 3217 * alignment, we don't know the exact position of the 3218 * initialization vector. We must assume worst case. 3219 */ 3220 iv_size_padding = align_mask; 3221 } 3222 3223 /* ...| IV + padding | original IV | original sec. number | bio tag offset | */ 3224 additional_req_size = sizeof(struct dm_crypt_request) + 3225 iv_size_padding + cc->iv_size + 3226 cc->iv_size + 3227 sizeof(uint64_t) + 3228 sizeof(unsigned int); 3229 3230 ret = mempool_init_kmalloc_pool(&cc->req_pool, MIN_IOS, cc->dmreq_start + additional_req_size); 3231 if (ret) { 3232 ti->error = "Cannot allocate crypt request mempool"; 3233 goto bad; 3234 } 3235 3236 cc->per_bio_data_size = ti->per_io_data_size = 3237 ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size, 3238 ARCH_KMALLOC_MINALIGN); 3239 3240 ret = mempool_init(&cc->page_pool, BIO_MAX_PAGES, crypt_page_alloc, crypt_page_free, cc); 3241 if (ret) { 3242 ti->error = "Cannot allocate page mempool"; 3243 goto bad; 3244 } 3245 3246 ret = bioset_init(&cc->bs, MIN_IOS, 0, BIOSET_NEED_BVECS); 3247 if (ret) { 3248 ti->error = "Cannot allocate crypt bioset"; 3249 goto bad; 3250 } 3251 3252 mutex_init(&cc->bio_alloc_lock); 3253 3254 ret = -EINVAL; 3255 if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) || 3256 (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) { 3257 ti->error = "Invalid iv_offset sector"; 3258 goto bad; 3259 } 3260 cc->iv_offset = tmpll; 3261 3262 ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev); 3263 if (ret) { 3264 ti->error = "Device lookup failed"; 3265 goto bad; 3266 } 3267 3268 ret = -EINVAL; 3269 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) { 3270 ti->error = "Invalid device sector"; 3271 goto bad; 3272 } 3273 cc->start = tmpll; 3274 3275 /* 3276 * For zoned block devices, we need to preserve the issuer write 3277 * ordering. To do so, disable write workqueues and force inline 3278 * encryption completion. 3279 */ 3280 if (bdev_is_zoned(cc->dev->bdev)) { 3281 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3282 set_bit(DM_CRYPT_WRITE_INLINE, &cc->flags); 3283 } 3284 3285 if (crypt_integrity_aead(cc) || cc->integrity_iv_size) { 3286 ret = crypt_integrity_ctr(cc, ti); 3287 if (ret) 3288 goto bad; 3289 3290 cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->on_disk_tag_size; 3291 if (!cc->tag_pool_max_sectors) 3292 cc->tag_pool_max_sectors = 1; 3293 3294 ret = mempool_init_kmalloc_pool(&cc->tag_pool, MIN_IOS, 3295 cc->tag_pool_max_sectors * cc->on_disk_tag_size); 3296 if (ret) { 3297 ti->error = "Cannot allocate integrity tags mempool"; 3298 goto bad; 3299 } 3300 3301 cc->tag_pool_max_sectors <<= cc->sector_shift; 3302 } 3303 3304 ret = -ENOMEM; 3305 cc->io_queue = alloc_workqueue("kcryptd_io/%s", WQ_MEM_RECLAIM, 1, devname); 3306 if (!cc->io_queue) { 3307 ti->error = "Couldn't create kcryptd io queue"; 3308 goto bad; 3309 } 3310 3311 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3312 cc->crypt_queue = alloc_workqueue("kcryptd/%s", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 3313 1, devname); 3314 else 3315 cc->crypt_queue = alloc_workqueue("kcryptd/%s", 3316 WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND, 3317 num_online_cpus(), devname); 3318 if (!cc->crypt_queue) { 3319 ti->error = "Couldn't create kcryptd queue"; 3320 goto bad; 3321 } 3322 3323 spin_lock_init(&cc->write_thread_lock); 3324 cc->write_tree = RB_ROOT; 3325 3326 cc->write_thread = kthread_create(dmcrypt_write, cc, "dmcrypt_write/%s", devname); 3327 if (IS_ERR(cc->write_thread)) { 3328 ret = PTR_ERR(cc->write_thread); 3329 cc->write_thread = NULL; 3330 ti->error = "Couldn't spawn write thread"; 3331 goto bad; 3332 } 3333 wake_up_process(cc->write_thread); 3334 3335 ti->num_flush_bios = 1; 3336 ti->limit_swap_bios = true; 3337 3338 return 0; 3339 3340bad: 3341 crypt_dtr(ti); 3342 return ret; 3343} 3344 3345static int crypt_map(struct dm_target *ti, struct bio *bio) 3346{ 3347 struct dm_crypt_io *io; 3348 struct crypt_config *cc = ti->private; 3349 3350 /* 3351 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues. 3352 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight 3353 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters 3354 */ 3355 if (unlikely(bio->bi_opf & REQ_PREFLUSH || 3356 bio_op(bio) == REQ_OP_DISCARD)) { 3357 bio_set_dev(bio, cc->dev->bdev); 3358 if (bio_sectors(bio)) 3359 bio->bi_iter.bi_sector = cc->start + 3360 dm_target_offset(ti, bio->bi_iter.bi_sector); 3361 return DM_MAPIO_REMAPPED; 3362 } 3363 3364 /* 3365 * Check if bio is too large, split as needed. 3366 */ 3367 if (unlikely(bio->bi_iter.bi_size > (BIO_MAX_PAGES << PAGE_SHIFT)) && 3368 (bio_data_dir(bio) == WRITE || cc->on_disk_tag_size)) 3369 dm_accept_partial_bio(bio, ((BIO_MAX_PAGES << PAGE_SHIFT) >> SECTOR_SHIFT)); 3370 3371 /* 3372 * Ensure that bio is a multiple of internal sector encryption size 3373 * and is aligned to this size as defined in IO hints. 3374 */ 3375 if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0)) 3376 return DM_MAPIO_KILL; 3377 3378 if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1))) 3379 return DM_MAPIO_KILL; 3380 3381 io = dm_per_bio_data(bio, cc->per_bio_data_size); 3382 crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector)); 3383 3384 if (cc->on_disk_tag_size) { 3385 unsigned tag_len = cc->on_disk_tag_size * (bio_sectors(bio) >> cc->sector_shift); 3386 3387 if (unlikely(tag_len > KMALLOC_MAX_SIZE) || 3388 unlikely(!(io->integrity_metadata = kmalloc(tag_len, 3389 GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN)))) { 3390 if (bio_sectors(bio) > cc->tag_pool_max_sectors) 3391 dm_accept_partial_bio(bio, cc->tag_pool_max_sectors); 3392 io->integrity_metadata = mempool_alloc(&cc->tag_pool, GFP_NOIO); 3393 io->integrity_metadata_from_pool = true; 3394 } 3395 } 3396 3397 if (crypt_integrity_aead(cc)) 3398 io->ctx.r.req_aead = (struct aead_request *)(io + 1); 3399 else 3400 io->ctx.r.req = (struct skcipher_request *)(io + 1); 3401 3402 if (bio_data_dir(io->base_bio) == READ) { 3403 if (kcryptd_io_read(io, GFP_NOWAIT)) 3404 kcryptd_queue_read(io); 3405 } else 3406 kcryptd_queue_crypt(io); 3407 3408 return DM_MAPIO_SUBMITTED; 3409} 3410 3411static char hex2asc(unsigned char c) 3412{ 3413 return c + '0' + ((unsigned)(9 - c) >> 4 & 0x27); 3414} 3415 3416static void crypt_status(struct dm_target *ti, status_type_t type, 3417 unsigned status_flags, char *result, unsigned maxlen) 3418{ 3419 struct crypt_config *cc = ti->private; 3420 unsigned i, sz = 0; 3421 int num_feature_args = 0; 3422 3423 switch (type) { 3424 case STATUSTYPE_INFO: 3425 result[0] = '\0'; 3426 break; 3427 3428 case STATUSTYPE_TABLE: 3429 DMEMIT("%s ", cc->cipher_string); 3430 3431 if (cc->key_size > 0) { 3432 if (cc->key_string) 3433 DMEMIT(":%u:%s", cc->key_size, cc->key_string); 3434 else { 3435 for (i = 0; i < cc->key_size; i++) { 3436 DMEMIT("%c%c", hex2asc(cc->key[i] >> 4), 3437 hex2asc(cc->key[i] & 0xf)); 3438 } 3439 } 3440 } else 3441 DMEMIT("-"); 3442 3443 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, 3444 cc->dev->name, (unsigned long long)cc->start); 3445 3446 num_feature_args += !!ti->num_discard_bios; 3447 num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3448 num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3449 num_feature_args += test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3450 num_feature_args += test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3451 num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT); 3452 num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3453 if (cc->on_disk_tag_size) 3454 num_feature_args++; 3455 if (num_feature_args) { 3456 DMEMIT(" %d", num_feature_args); 3457 if (ti->num_discard_bios) 3458 DMEMIT(" allow_discards"); 3459 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3460 DMEMIT(" same_cpu_crypt"); 3461 if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) 3462 DMEMIT(" submit_from_crypt_cpus"); 3463 if (test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) 3464 DMEMIT(" no_read_workqueue"); 3465 if (test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) 3466 DMEMIT(" no_write_workqueue"); 3467 if (cc->on_disk_tag_size) 3468 DMEMIT(" integrity:%u:%s", cc->on_disk_tag_size, cc->cipher_auth); 3469 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3470 DMEMIT(" sector_size:%d", cc->sector_size); 3471 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 3472 DMEMIT(" iv_large_sectors"); 3473 } 3474 3475 break; 3476 } 3477} 3478 3479static void crypt_postsuspend(struct dm_target *ti) 3480{ 3481 struct crypt_config *cc = ti->private; 3482 3483 set_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3484} 3485 3486static int crypt_preresume(struct dm_target *ti) 3487{ 3488 struct crypt_config *cc = ti->private; 3489 3490 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { 3491 DMERR("aborting resume - crypt key is not set."); 3492 return -EAGAIN; 3493 } 3494 3495 return 0; 3496} 3497 3498static void crypt_resume(struct dm_target *ti) 3499{ 3500 struct crypt_config *cc = ti->private; 3501 3502 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3503} 3504 3505/* Message interface 3506 * key set <key> 3507 * key wipe 3508 */ 3509static int crypt_message(struct dm_target *ti, unsigned argc, char **argv, 3510 char *result, unsigned maxlen) 3511{ 3512 struct crypt_config *cc = ti->private; 3513 int key_size, ret = -EINVAL; 3514 3515 if (argc < 2) 3516 goto error; 3517 3518 if (!strcasecmp(argv[0], "key")) { 3519 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { 3520 DMWARN("not suspended during key manipulation."); 3521 return -EINVAL; 3522 } 3523 if (argc == 3 && !strcasecmp(argv[1], "set")) { 3524 /* The key size may not be changed. */ 3525 key_size = get_key_size(&argv[2]); 3526 if (key_size < 0 || cc->key_size != key_size) { 3527 memset(argv[2], '0', strlen(argv[2])); 3528 return -EINVAL; 3529 } 3530 3531 ret = crypt_set_key(cc, argv[2]); 3532 if (ret) 3533 return ret; 3534 if (cc->iv_gen_ops && cc->iv_gen_ops->init) 3535 ret = cc->iv_gen_ops->init(cc); 3536 /* wipe the kernel key payload copy */ 3537 if (cc->key_string) 3538 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3539 return ret; 3540 } 3541 if (argc == 2 && !strcasecmp(argv[1], "wipe")) 3542 return crypt_wipe_key(cc); 3543 } 3544 3545error: 3546 DMWARN("unrecognised message received."); 3547 return -EINVAL; 3548} 3549 3550static int crypt_iterate_devices(struct dm_target *ti, 3551 iterate_devices_callout_fn fn, void *data) 3552{ 3553 struct crypt_config *cc = ti->private; 3554 3555 return fn(ti, cc->dev, cc->start, ti->len, data); 3556} 3557 3558static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits) 3559{ 3560 struct crypt_config *cc = ti->private; 3561 3562 /* 3563 * Unfortunate constraint that is required to avoid the potential 3564 * for exceeding underlying device's max_segments limits -- due to 3565 * crypt_alloc_buffer() possibly allocating pages for the encryption 3566 * bio that are not as physically contiguous as the original bio. 3567 */ 3568 limits->max_segment_size = PAGE_SIZE; 3569 3570 limits->logical_block_size = 3571 max_t(unsigned, limits->logical_block_size, cc->sector_size); 3572 limits->physical_block_size = 3573 max_t(unsigned, limits->physical_block_size, cc->sector_size); 3574 limits->io_min = max_t(unsigned, limits->io_min, cc->sector_size); 3575} 3576 3577static struct target_type crypt_target = { 3578 .name = "crypt", 3579 .version = {1, 22, 0}, 3580 .module = THIS_MODULE, 3581 .ctr = crypt_ctr, 3582 .dtr = crypt_dtr, 3583#ifdef CONFIG_BLK_DEV_ZONED 3584 .features = DM_TARGET_ZONED_HM, 3585 .report_zones = crypt_report_zones, 3586#endif 3587 .map = crypt_map, 3588 .status = crypt_status, 3589 .postsuspend = crypt_postsuspend, 3590 .preresume = crypt_preresume, 3591 .resume = crypt_resume, 3592 .message = crypt_message, 3593 .iterate_devices = crypt_iterate_devices, 3594 .io_hints = crypt_io_hints, 3595}; 3596 3597static int __init dm_crypt_init(void) 3598{ 3599 int r; 3600 3601 r = dm_register_target(&crypt_target); 3602 if (r < 0) 3603 DMERR("register failed %d", r); 3604 3605 return r; 3606} 3607 3608static void __exit dm_crypt_exit(void) 3609{ 3610 dm_unregister_target(&crypt_target); 3611} 3612 3613module_init(dm_crypt_init); 3614module_exit(dm_crypt_exit); 3615 3616MODULE_AUTHOR("Jana Saout <jana@saout.de>"); 3617MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); 3618MODULE_LICENSE("GPL"); 3619