1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (C) 2003 Jana Saout <jana@saout.de> 4 * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org> 5 * Copyright (C) 2006-2020 Red Hat, Inc. All rights reserved. 6 * Copyright (C) 2013-2020 Milan Broz <gmazyland@gmail.com> 7 * 8 * This file is released under the GPL. 9 */ 10 11 #include <linux/completion.h> 12 #include <linux/err.h> 13 #include <linux/module.h> 14 #include <linux/init.h> 15 #include <linux/kernel.h> 16 #include <linux/key.h> 17 #include <linux/bio.h> 18 #include <linux/blkdev.h> 19 #include <linux/blk-integrity.h> 20 #include <linux/mempool.h> 21 #include <linux/slab.h> 22 #include <linux/crypto.h> 23 #include <linux/workqueue.h> 24 #include <linux/kthread.h> 25 #include <linux/backing-dev.h> 26 #include <linux/atomic.h> 27 #include <linux/scatterlist.h> 28 #include <linux/rbtree.h> 29 #include <linux/ctype.h> 30 #include <asm/page.h> 31 #include <asm/unaligned.h> 32 #include <crypto/hash.h> 33 #include <crypto/md5.h> 34 #include <crypto/algapi.h> 35 #include <crypto/skcipher.h> 36 #include <crypto/aead.h> 37 #include <crypto/authenc.h> 38 #include <linux/rtnetlink.h> /* for struct rtattr and RTA macros only */ 39 #include <linux/key-type.h> 40 #include <keys/user-type.h> 41 #include <keys/encrypted-type.h> 42 #include <keys/trusted-type.h> 43 44 #include <linux/device-mapper.h> 45 46 #include "dm-audit.h" 47 48 #define DM_MSG_PREFIX "crypt" 49 50 /* 51 * context holding the current state of a multi-part conversion 52 */ 53 struct convert_context { 54 struct completion restart; 55 struct bio *bio_in; 56 struct bio *bio_out; 57 struct bvec_iter iter_in; 58 struct bvec_iter iter_out; 59 u64 cc_sector; 60 atomic_t cc_pending; 61 union { 62 struct skcipher_request *req; 63 struct aead_request *req_aead; 64 } r; 65 66 }; 67 68 /* 69 * per bio private data 70 */ 71 struct dm_crypt_io { 72 struct crypt_config *cc; 73 struct bio *base_bio; 74 u8 *integrity_metadata; 75 bool integrity_metadata_from_pool; 76 struct work_struct work; 77 struct tasklet_struct tasklet; 78 79 struct convert_context ctx; 80 81 atomic_t io_pending; 82 blk_status_t error; 83 sector_t sector; 84 85 struct rb_node rb_node; 86 } CRYPTO_MINALIGN_ATTR; 87 88 struct dm_crypt_request { 89 struct convert_context *ctx; 90 struct scatterlist sg_in[4]; 91 struct scatterlist sg_out[4]; 92 u64 iv_sector; 93 }; 94 95 struct crypt_config; 96 97 struct crypt_iv_operations { 98 int (*ctr)(struct crypt_config *cc, struct dm_target *ti, 99 const char *opts); 100 void (*dtr)(struct crypt_config *cc); 101 int (*init)(struct crypt_config *cc); 102 int (*wipe)(struct crypt_config *cc); 103 int (*generator)(struct crypt_config *cc, u8 *iv, 104 struct dm_crypt_request *dmreq); 105 int (*post)(struct crypt_config *cc, u8 *iv, 106 struct dm_crypt_request *dmreq); 107 }; 108 109 struct iv_benbi_private { 110 int shift; 111 }; 112 113 #define LMK_SEED_SIZE 64 /* hash + 0 */ 114 struct iv_lmk_private { 115 struct crypto_shash *hash_tfm; 116 u8 *seed; 117 }; 118 119 #define TCW_WHITENING_SIZE 16 120 struct iv_tcw_private { 121 struct crypto_shash *crc32_tfm; 122 u8 *iv_seed; 123 u8 *whitening; 124 }; 125 126 #define ELEPHANT_MAX_KEY_SIZE 32 127 struct iv_elephant_private { 128 struct crypto_skcipher *tfm; 129 }; 130 131 /* 132 * Crypt: maps a linear range of a block device 133 * and encrypts / decrypts at the same time. 134 */ 135 enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID, 136 DM_CRYPT_SAME_CPU, DM_CRYPT_NO_OFFLOAD, 137 DM_CRYPT_NO_READ_WORKQUEUE, DM_CRYPT_NO_WRITE_WORKQUEUE, 138 DM_CRYPT_WRITE_INLINE }; 139 140 enum cipher_flags { 141 CRYPT_MODE_INTEGRITY_AEAD, /* Use authenticated mode for cipher */ 142 CRYPT_IV_LARGE_SECTORS, /* Calculate IV from sector_size, not 512B sectors */ 143 CRYPT_ENCRYPT_PREPROCESS, /* Must preprocess data for encryption (elephant) */ 144 }; 145 146 /* 147 * The fields in here must be read only after initialization. 148 */ 149 struct crypt_config { 150 struct dm_dev *dev; 151 sector_t start; 152 153 struct percpu_counter n_allocated_pages; 154 155 struct workqueue_struct *io_queue; 156 struct workqueue_struct *crypt_queue; 157 158 spinlock_t write_thread_lock; 159 struct task_struct *write_thread; 160 struct rb_root write_tree; 161 162 char *cipher_string; 163 char *cipher_auth; 164 char *key_string; 165 166 const struct crypt_iv_operations *iv_gen_ops; 167 union { 168 struct iv_benbi_private benbi; 169 struct iv_lmk_private lmk; 170 struct iv_tcw_private tcw; 171 struct iv_elephant_private elephant; 172 } iv_gen_private; 173 u64 iv_offset; 174 unsigned int iv_size; 175 unsigned short sector_size; 176 unsigned char sector_shift; 177 178 union { 179 struct crypto_skcipher **tfms; 180 struct crypto_aead **tfms_aead; 181 } cipher_tfm; 182 unsigned int tfms_count; 183 unsigned long cipher_flags; 184 185 /* 186 * Layout of each crypto request: 187 * 188 * struct skcipher_request 189 * context 190 * padding 191 * struct dm_crypt_request 192 * padding 193 * IV 194 * 195 * The padding is added so that dm_crypt_request and the IV are 196 * correctly aligned. 197 */ 198 unsigned int dmreq_start; 199 200 unsigned int per_bio_data_size; 201 202 unsigned long flags; 203 unsigned int key_size; 204 unsigned int key_parts; /* independent parts in key buffer */ 205 unsigned int key_extra_size; /* additional keys length */ 206 unsigned int key_mac_size; /* MAC key size for authenc(...) */ 207 208 unsigned int integrity_tag_size; 209 unsigned int integrity_iv_size; 210 unsigned int on_disk_tag_size; 211 212 /* 213 * pool for per bio private data, crypto requests, 214 * encryption requeusts/buffer pages and integrity tags 215 */ 216 unsigned int tag_pool_max_sectors; 217 mempool_t tag_pool; 218 mempool_t req_pool; 219 mempool_t page_pool; 220 221 struct bio_set bs; 222 struct mutex bio_alloc_lock; 223 224 u8 *authenc_key; /* space for keys in authenc() format (if used) */ 225 u8 key[]; 226 }; 227 228 #define MIN_IOS 64 229 #define MAX_TAG_SIZE 480 230 #define POOL_ENTRY_SIZE 512 231 232 static DEFINE_SPINLOCK(dm_crypt_clients_lock); 233 static unsigned int dm_crypt_clients_n = 0; 234 static volatile unsigned long dm_crypt_pages_per_client; 235 #define DM_CRYPT_MEMORY_PERCENT 2 236 #define DM_CRYPT_MIN_PAGES_PER_CLIENT (BIO_MAX_VECS * 16) 237 238 static void crypt_endio(struct bio *clone); 239 static void kcryptd_queue_crypt(struct dm_crypt_io *io); 240 static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 241 struct scatterlist *sg); 242 243 static bool crypt_integrity_aead(struct crypt_config *cc); 244 245 /* 246 * Use this to access cipher attributes that are independent of the key. 247 */ 248 static struct crypto_skcipher *any_tfm(struct crypt_config *cc) 249 { 250 return cc->cipher_tfm.tfms[0]; 251 } 252 253 static struct crypto_aead *any_tfm_aead(struct crypt_config *cc) 254 { 255 return cc->cipher_tfm.tfms_aead[0]; 256 } 257 258 /* 259 * Different IV generation algorithms: 260 * 261 * plain: the initial vector is the 32-bit little-endian version of the sector 262 * number, padded with zeros if necessary. 263 * 264 * plain64: the initial vector is the 64-bit little-endian version of the sector 265 * number, padded with zeros if necessary. 266 * 267 * plain64be: the initial vector is the 64-bit big-endian version of the sector 268 * number, padded with zeros if necessary. 269 * 270 * essiv: "encrypted sector|salt initial vector", the sector number is 271 * encrypted with the bulk cipher using a salt as key. The salt 272 * should be derived from the bulk cipher's key via hashing. 273 * 274 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 275 * (needed for LRW-32-AES and possible other narrow block modes) 276 * 277 * null: the initial vector is always zero. Provides compatibility with 278 * obsolete loop_fish2 devices. Do not use for new devices. 279 * 280 * lmk: Compatible implementation of the block chaining mode used 281 * by the Loop-AES block device encryption system 282 * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/ 283 * It operates on full 512 byte sectors and uses CBC 284 * with an IV derived from the sector number, the data and 285 * optionally extra IV seed. 286 * This means that after decryption the first block 287 * of sector must be tweaked according to decrypted data. 288 * Loop-AES can use three encryption schemes: 289 * version 1: is plain aes-cbc mode 290 * version 2: uses 64 multikey scheme with lmk IV generator 291 * version 3: the same as version 2 with additional IV seed 292 * (it uses 65 keys, last key is used as IV seed) 293 * 294 * tcw: Compatible implementation of the block chaining mode used 295 * by the TrueCrypt device encryption system (prior to version 4.1). 296 * For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat 297 * It operates on full 512 byte sectors and uses CBC 298 * with an IV derived from initial key and the sector number. 299 * In addition, whitening value is applied on every sector, whitening 300 * is calculated from initial key, sector number and mixed using CRC32. 301 * Note that this encryption scheme is vulnerable to watermarking attacks 302 * and should be used for old compatible containers access only. 303 * 304 * eboiv: Encrypted byte-offset IV (used in Bitlocker in CBC mode) 305 * The IV is encrypted little-endian byte-offset (with the same key 306 * and cipher as the volume). 307 * 308 * elephant: The extended version of eboiv with additional Elephant diffuser 309 * used with Bitlocker CBC mode. 310 * This mode was used in older Windows systems 311 * https://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf 312 */ 313 314 static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, 315 struct dm_crypt_request *dmreq) 316 { 317 memset(iv, 0, cc->iv_size); 318 *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff); 319 320 return 0; 321 } 322 323 static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv, 324 struct dm_crypt_request *dmreq) 325 { 326 memset(iv, 0, cc->iv_size); 327 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 328 329 return 0; 330 } 331 332 static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv, 333 struct dm_crypt_request *dmreq) 334 { 335 memset(iv, 0, cc->iv_size); 336 /* iv_size is at least of size u64; usually it is 16 bytes */ 337 *(__be64 *)&iv[cc->iv_size - sizeof(u64)] = cpu_to_be64(dmreq->iv_sector); 338 339 return 0; 340 } 341 342 static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, 343 struct dm_crypt_request *dmreq) 344 { 345 /* 346 * ESSIV encryption of the IV is now handled by the crypto API, 347 * so just pass the plain sector number here. 348 */ 349 memset(iv, 0, cc->iv_size); 350 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 351 352 return 0; 353 } 354 355 static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, 356 const char *opts) 357 { 358 unsigned int bs; 359 int log; 360 361 if (crypt_integrity_aead(cc)) 362 bs = crypto_aead_blocksize(any_tfm_aead(cc)); 363 else 364 bs = crypto_skcipher_blocksize(any_tfm(cc)); 365 log = ilog2(bs); 366 367 /* we need to calculate how far we must shift the sector count 368 * to get the cipher block count, we use this shift in _gen */ 369 370 if (1 << log != bs) { 371 ti->error = "cypher blocksize is not a power of 2"; 372 return -EINVAL; 373 } 374 375 if (log > 9) { 376 ti->error = "cypher blocksize is > 512"; 377 return -EINVAL; 378 } 379 380 cc->iv_gen_private.benbi.shift = 9 - log; 381 382 return 0; 383 } 384 385 static void crypt_iv_benbi_dtr(struct crypt_config *cc) 386 { 387 } 388 389 static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, 390 struct dm_crypt_request *dmreq) 391 { 392 __be64 val; 393 394 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ 395 396 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1); 397 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); 398 399 return 0; 400 } 401 402 static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, 403 struct dm_crypt_request *dmreq) 404 { 405 memset(iv, 0, cc->iv_size); 406 407 return 0; 408 } 409 410 static void crypt_iv_lmk_dtr(struct crypt_config *cc) 411 { 412 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 413 414 if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm)) 415 crypto_free_shash(lmk->hash_tfm); 416 lmk->hash_tfm = NULL; 417 418 kfree_sensitive(lmk->seed); 419 lmk->seed = NULL; 420 } 421 422 static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti, 423 const char *opts) 424 { 425 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 426 427 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 428 ti->error = "Unsupported sector size for LMK"; 429 return -EINVAL; 430 } 431 432 lmk->hash_tfm = crypto_alloc_shash("md5", 0, 433 CRYPTO_ALG_ALLOCATES_MEMORY); 434 if (IS_ERR(lmk->hash_tfm)) { 435 ti->error = "Error initializing LMK hash"; 436 return PTR_ERR(lmk->hash_tfm); 437 } 438 439 /* No seed in LMK version 2 */ 440 if (cc->key_parts == cc->tfms_count) { 441 lmk->seed = NULL; 442 return 0; 443 } 444 445 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL); 446 if (!lmk->seed) { 447 crypt_iv_lmk_dtr(cc); 448 ti->error = "Error kmallocing seed storage in LMK"; 449 return -ENOMEM; 450 } 451 452 return 0; 453 } 454 455 static int crypt_iv_lmk_init(struct crypt_config *cc) 456 { 457 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 458 int subkey_size = cc->key_size / cc->key_parts; 459 460 /* LMK seed is on the position of LMK_KEYS + 1 key */ 461 if (lmk->seed) 462 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size), 463 crypto_shash_digestsize(lmk->hash_tfm)); 464 465 return 0; 466 } 467 468 static int crypt_iv_lmk_wipe(struct crypt_config *cc) 469 { 470 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 471 472 if (lmk->seed) 473 memset(lmk->seed, 0, LMK_SEED_SIZE); 474 475 return 0; 476 } 477 478 static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv, 479 struct dm_crypt_request *dmreq, 480 u8 *data) 481 { 482 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 483 SHASH_DESC_ON_STACK(desc, lmk->hash_tfm); 484 struct md5_state md5state; 485 __le32 buf[4]; 486 int i, r; 487 488 desc->tfm = lmk->hash_tfm; 489 490 r = crypto_shash_init(desc); 491 if (r) 492 return r; 493 494 if (lmk->seed) { 495 r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE); 496 if (r) 497 return r; 498 } 499 500 /* Sector is always 512B, block size 16, add data of blocks 1-31 */ 501 r = crypto_shash_update(desc, data + 16, 16 * 31); 502 if (r) 503 return r; 504 505 /* Sector is cropped to 56 bits here */ 506 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF); 507 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000); 508 buf[2] = cpu_to_le32(4024); 509 buf[3] = 0; 510 r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf)); 511 if (r) 512 return r; 513 514 /* No MD5 padding here */ 515 r = crypto_shash_export(desc, &md5state); 516 if (r) 517 return r; 518 519 for (i = 0; i < MD5_HASH_WORDS; i++) 520 __cpu_to_le32s(&md5state.hash[i]); 521 memcpy(iv, &md5state.hash, cc->iv_size); 522 523 return 0; 524 } 525 526 static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv, 527 struct dm_crypt_request *dmreq) 528 { 529 struct scatterlist *sg; 530 u8 *src; 531 int r = 0; 532 533 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 534 sg = crypt_get_sg_data(cc, dmreq->sg_in); 535 src = kmap_local_page(sg_page(sg)); 536 r = crypt_iv_lmk_one(cc, iv, dmreq, src + sg->offset); 537 kunmap_local(src); 538 } else 539 memset(iv, 0, cc->iv_size); 540 541 return r; 542 } 543 544 static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv, 545 struct dm_crypt_request *dmreq) 546 { 547 struct scatterlist *sg; 548 u8 *dst; 549 int r; 550 551 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) 552 return 0; 553 554 sg = crypt_get_sg_data(cc, dmreq->sg_out); 555 dst = kmap_local_page(sg_page(sg)); 556 r = crypt_iv_lmk_one(cc, iv, dmreq, dst + sg->offset); 557 558 /* Tweak the first block of plaintext sector */ 559 if (!r) 560 crypto_xor(dst + sg->offset, iv, cc->iv_size); 561 562 kunmap_local(dst); 563 return r; 564 } 565 566 static void crypt_iv_tcw_dtr(struct crypt_config *cc) 567 { 568 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 569 570 kfree_sensitive(tcw->iv_seed); 571 tcw->iv_seed = NULL; 572 kfree_sensitive(tcw->whitening); 573 tcw->whitening = NULL; 574 575 if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm)) 576 crypto_free_shash(tcw->crc32_tfm); 577 tcw->crc32_tfm = NULL; 578 } 579 580 static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti, 581 const char *opts) 582 { 583 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 584 585 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 586 ti->error = "Unsupported sector size for TCW"; 587 return -EINVAL; 588 } 589 590 if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) { 591 ti->error = "Wrong key size for TCW"; 592 return -EINVAL; 593 } 594 595 tcw->crc32_tfm = crypto_alloc_shash("crc32", 0, 596 CRYPTO_ALG_ALLOCATES_MEMORY); 597 if (IS_ERR(tcw->crc32_tfm)) { 598 ti->error = "Error initializing CRC32 in TCW"; 599 return PTR_ERR(tcw->crc32_tfm); 600 } 601 602 tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL); 603 tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL); 604 if (!tcw->iv_seed || !tcw->whitening) { 605 crypt_iv_tcw_dtr(cc); 606 ti->error = "Error allocating seed storage in TCW"; 607 return -ENOMEM; 608 } 609 610 return 0; 611 } 612 613 static int crypt_iv_tcw_init(struct crypt_config *cc) 614 { 615 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 616 int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE; 617 618 memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size); 619 memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size], 620 TCW_WHITENING_SIZE); 621 622 return 0; 623 } 624 625 static int crypt_iv_tcw_wipe(struct crypt_config *cc) 626 { 627 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 628 629 memset(tcw->iv_seed, 0, cc->iv_size); 630 memset(tcw->whitening, 0, TCW_WHITENING_SIZE); 631 632 return 0; 633 } 634 635 static int crypt_iv_tcw_whitening(struct crypt_config *cc, 636 struct dm_crypt_request *dmreq, 637 u8 *data) 638 { 639 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 640 __le64 sector = cpu_to_le64(dmreq->iv_sector); 641 u8 buf[TCW_WHITENING_SIZE]; 642 SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm); 643 int i, r; 644 645 /* xor whitening with sector number */ 646 crypto_xor_cpy(buf, tcw->whitening, (u8 *)§or, 8); 647 crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)§or, 8); 648 649 /* calculate crc32 for every 32bit part and xor it */ 650 desc->tfm = tcw->crc32_tfm; 651 for (i = 0; i < 4; i++) { 652 r = crypto_shash_init(desc); 653 if (r) 654 goto out; 655 r = crypto_shash_update(desc, &buf[i * 4], 4); 656 if (r) 657 goto out; 658 r = crypto_shash_final(desc, &buf[i * 4]); 659 if (r) 660 goto out; 661 } 662 crypto_xor(&buf[0], &buf[12], 4); 663 crypto_xor(&buf[4], &buf[8], 4); 664 665 /* apply whitening (8 bytes) to whole sector */ 666 for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++) 667 crypto_xor(data + i * 8, buf, 8); 668 out: 669 memzero_explicit(buf, sizeof(buf)); 670 return r; 671 } 672 673 static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv, 674 struct dm_crypt_request *dmreq) 675 { 676 struct scatterlist *sg; 677 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 678 __le64 sector = cpu_to_le64(dmreq->iv_sector); 679 u8 *src; 680 int r = 0; 681 682 /* Remove whitening from ciphertext */ 683 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 684 sg = crypt_get_sg_data(cc, dmreq->sg_in); 685 src = kmap_local_page(sg_page(sg)); 686 r = crypt_iv_tcw_whitening(cc, dmreq, src + sg->offset); 687 kunmap_local(src); 688 } 689 690 /* Calculate IV */ 691 crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)§or, 8); 692 if (cc->iv_size > 8) 693 crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)§or, 694 cc->iv_size - 8); 695 696 return r; 697 } 698 699 static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv, 700 struct dm_crypt_request *dmreq) 701 { 702 struct scatterlist *sg; 703 u8 *dst; 704 int r; 705 706 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 707 return 0; 708 709 /* Apply whitening on ciphertext */ 710 sg = crypt_get_sg_data(cc, dmreq->sg_out); 711 dst = kmap_local_page(sg_page(sg)); 712 r = crypt_iv_tcw_whitening(cc, dmreq, dst + sg->offset); 713 kunmap_local(dst); 714 715 return r; 716 } 717 718 static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv, 719 struct dm_crypt_request *dmreq) 720 { 721 /* Used only for writes, there must be an additional space to store IV */ 722 get_random_bytes(iv, cc->iv_size); 723 return 0; 724 } 725 726 static int crypt_iv_eboiv_ctr(struct crypt_config *cc, struct dm_target *ti, 727 const char *opts) 728 { 729 if (crypt_integrity_aead(cc)) { 730 ti->error = "AEAD transforms not supported for EBOIV"; 731 return -EINVAL; 732 } 733 734 if (crypto_skcipher_blocksize(any_tfm(cc)) != cc->iv_size) { 735 ti->error = "Block size of EBOIV cipher does " 736 "not match IV size of block cipher"; 737 return -EINVAL; 738 } 739 740 return 0; 741 } 742 743 static int crypt_iv_eboiv_gen(struct crypt_config *cc, u8 *iv, 744 struct dm_crypt_request *dmreq) 745 { 746 u8 buf[MAX_CIPHER_BLOCKSIZE] __aligned(__alignof__(__le64)); 747 struct skcipher_request *req; 748 struct scatterlist src, dst; 749 DECLARE_CRYPTO_WAIT(wait); 750 int err; 751 752 req = skcipher_request_alloc(any_tfm(cc), GFP_NOIO); 753 if (!req) 754 return -ENOMEM; 755 756 memset(buf, 0, cc->iv_size); 757 *(__le64 *)buf = cpu_to_le64(dmreq->iv_sector * cc->sector_size); 758 759 sg_init_one(&src, page_address(ZERO_PAGE(0)), cc->iv_size); 760 sg_init_one(&dst, iv, cc->iv_size); 761 skcipher_request_set_crypt(req, &src, &dst, cc->iv_size, buf); 762 skcipher_request_set_callback(req, 0, crypto_req_done, &wait); 763 err = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 764 skcipher_request_free(req); 765 766 return err; 767 } 768 769 static void crypt_iv_elephant_dtr(struct crypt_config *cc) 770 { 771 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 772 773 crypto_free_skcipher(elephant->tfm); 774 elephant->tfm = NULL; 775 } 776 777 static int crypt_iv_elephant_ctr(struct crypt_config *cc, struct dm_target *ti, 778 const char *opts) 779 { 780 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 781 int r; 782 783 elephant->tfm = crypto_alloc_skcipher("ecb(aes)", 0, 784 CRYPTO_ALG_ALLOCATES_MEMORY); 785 if (IS_ERR(elephant->tfm)) { 786 r = PTR_ERR(elephant->tfm); 787 elephant->tfm = NULL; 788 return r; 789 } 790 791 r = crypt_iv_eboiv_ctr(cc, ti, NULL); 792 if (r) 793 crypt_iv_elephant_dtr(cc); 794 return r; 795 } 796 797 static void diffuser_disk_to_cpu(u32 *d, size_t n) 798 { 799 #ifndef __LITTLE_ENDIAN 800 int i; 801 802 for (i = 0; i < n; i++) 803 d[i] = le32_to_cpu((__le32)d[i]); 804 #endif 805 } 806 807 static void diffuser_cpu_to_disk(__le32 *d, size_t n) 808 { 809 #ifndef __LITTLE_ENDIAN 810 int i; 811 812 for (i = 0; i < n; i++) 813 d[i] = cpu_to_le32((u32)d[i]); 814 #endif 815 } 816 817 static void diffuser_a_decrypt(u32 *d, size_t n) 818 { 819 int i, i1, i2, i3; 820 821 for (i = 0; i < 5; i++) { 822 i1 = 0; 823 i2 = n - 2; 824 i3 = n - 5; 825 826 while (i1 < (n - 1)) { 827 d[i1] += d[i2] ^ (d[i3] << 9 | d[i3] >> 23); 828 i1++; i2++; i3++; 829 830 if (i3 >= n) 831 i3 -= n; 832 833 d[i1] += d[i2] ^ d[i3]; 834 i1++; i2++; i3++; 835 836 if (i2 >= n) 837 i2 -= n; 838 839 d[i1] += d[i2] ^ (d[i3] << 13 | d[i3] >> 19); 840 i1++; i2++; i3++; 841 842 d[i1] += d[i2] ^ d[i3]; 843 i1++; i2++; i3++; 844 } 845 } 846 } 847 848 static void diffuser_a_encrypt(u32 *d, size_t n) 849 { 850 int i, i1, i2, i3; 851 852 for (i = 0; i < 5; i++) { 853 i1 = n - 1; 854 i2 = n - 2 - 1; 855 i3 = n - 5 - 1; 856 857 while (i1 > 0) { 858 d[i1] -= d[i2] ^ d[i3]; 859 i1--; i2--; i3--; 860 861 d[i1] -= d[i2] ^ (d[i3] << 13 | d[i3] >> 19); 862 i1--; i2--; i3--; 863 864 if (i2 < 0) 865 i2 += n; 866 867 d[i1] -= d[i2] ^ d[i3]; 868 i1--; i2--; i3--; 869 870 if (i3 < 0) 871 i3 += n; 872 873 d[i1] -= d[i2] ^ (d[i3] << 9 | d[i3] >> 23); 874 i1--; i2--; i3--; 875 } 876 } 877 } 878 879 static void diffuser_b_decrypt(u32 *d, size_t n) 880 { 881 int i, i1, i2, i3; 882 883 for (i = 0; i < 3; i++) { 884 i1 = 0; 885 i2 = 2; 886 i3 = 5; 887 888 while (i1 < (n - 1)) { 889 d[i1] += d[i2] ^ d[i3]; 890 i1++; i2++; i3++; 891 892 d[i1] += d[i2] ^ (d[i3] << 10 | d[i3] >> 22); 893 i1++; i2++; i3++; 894 895 if (i2 >= n) 896 i2 -= n; 897 898 d[i1] += d[i2] ^ d[i3]; 899 i1++; i2++; i3++; 900 901 if (i3 >= n) 902 i3 -= n; 903 904 d[i1] += d[i2] ^ (d[i3] << 25 | d[i3] >> 7); 905 i1++; i2++; i3++; 906 } 907 } 908 } 909 910 static void diffuser_b_encrypt(u32 *d, size_t n) 911 { 912 int i, i1, i2, i3; 913 914 for (i = 0; i < 3; i++) { 915 i1 = n - 1; 916 i2 = 2 - 1; 917 i3 = 5 - 1; 918 919 while (i1 > 0) { 920 d[i1] -= d[i2] ^ (d[i3] << 25 | d[i3] >> 7); 921 i1--; i2--; i3--; 922 923 if (i3 < 0) 924 i3 += n; 925 926 d[i1] -= d[i2] ^ d[i3]; 927 i1--; i2--; i3--; 928 929 if (i2 < 0) 930 i2 += n; 931 932 d[i1] -= d[i2] ^ (d[i3] << 10 | d[i3] >> 22); 933 i1--; i2--; i3--; 934 935 d[i1] -= d[i2] ^ d[i3]; 936 i1--; i2--; i3--; 937 } 938 } 939 } 940 941 static int crypt_iv_elephant(struct crypt_config *cc, struct dm_crypt_request *dmreq) 942 { 943 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 944 u8 *es, *ks, *data, *data2, *data_offset; 945 struct skcipher_request *req; 946 struct scatterlist *sg, *sg2, src, dst; 947 DECLARE_CRYPTO_WAIT(wait); 948 int i, r; 949 950 req = skcipher_request_alloc(elephant->tfm, GFP_NOIO); 951 es = kzalloc(16, GFP_NOIO); /* Key for AES */ 952 ks = kzalloc(32, GFP_NOIO); /* Elephant sector key */ 953 954 if (!req || !es || !ks) { 955 r = -ENOMEM; 956 goto out; 957 } 958 959 *(__le64 *)es = cpu_to_le64(dmreq->iv_sector * cc->sector_size); 960 961 /* E(Ks, e(s)) */ 962 sg_init_one(&src, es, 16); 963 sg_init_one(&dst, ks, 16); 964 skcipher_request_set_crypt(req, &src, &dst, 16, NULL); 965 skcipher_request_set_callback(req, 0, crypto_req_done, &wait); 966 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 967 if (r) 968 goto out; 969 970 /* E(Ks, e'(s)) */ 971 es[15] = 0x80; 972 sg_init_one(&dst, &ks[16], 16); 973 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 974 if (r) 975 goto out; 976 977 sg = crypt_get_sg_data(cc, dmreq->sg_out); 978 data = kmap_local_page(sg_page(sg)); 979 data_offset = data + sg->offset; 980 981 /* Cannot modify original bio, copy to sg_out and apply Elephant to it */ 982 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 983 sg2 = crypt_get_sg_data(cc, dmreq->sg_in); 984 data2 = kmap_local_page(sg_page(sg2)); 985 memcpy(data_offset, data2 + sg2->offset, cc->sector_size); 986 kunmap_local(data2); 987 } 988 989 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 990 diffuser_disk_to_cpu((u32*)data_offset, cc->sector_size / sizeof(u32)); 991 diffuser_b_decrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 992 diffuser_a_decrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 993 diffuser_cpu_to_disk((__le32*)data_offset, cc->sector_size / sizeof(u32)); 994 } 995 996 for (i = 0; i < (cc->sector_size / 32); i++) 997 crypto_xor(data_offset + i * 32, ks, 32); 998 999 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 1000 diffuser_disk_to_cpu((u32*)data_offset, cc->sector_size / sizeof(u32)); 1001 diffuser_a_encrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 1002 diffuser_b_encrypt((u32*)data_offset, cc->sector_size / sizeof(u32)); 1003 diffuser_cpu_to_disk((__le32*)data_offset, cc->sector_size / sizeof(u32)); 1004 } 1005 1006 kunmap_local(data); 1007 out: 1008 kfree_sensitive(ks); 1009 kfree_sensitive(es); 1010 skcipher_request_free(req); 1011 return r; 1012 } 1013 1014 static int crypt_iv_elephant_gen(struct crypt_config *cc, u8 *iv, 1015 struct dm_crypt_request *dmreq) 1016 { 1017 int r; 1018 1019 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 1020 r = crypt_iv_elephant(cc, dmreq); 1021 if (r) 1022 return r; 1023 } 1024 1025 return crypt_iv_eboiv_gen(cc, iv, dmreq); 1026 } 1027 1028 static int crypt_iv_elephant_post(struct crypt_config *cc, u8 *iv, 1029 struct dm_crypt_request *dmreq) 1030 { 1031 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 1032 return crypt_iv_elephant(cc, dmreq); 1033 1034 return 0; 1035 } 1036 1037 static int crypt_iv_elephant_init(struct crypt_config *cc) 1038 { 1039 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 1040 int key_offset = cc->key_size - cc->key_extra_size; 1041 1042 return crypto_skcipher_setkey(elephant->tfm, &cc->key[key_offset], cc->key_extra_size); 1043 } 1044 1045 static int crypt_iv_elephant_wipe(struct crypt_config *cc) 1046 { 1047 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 1048 u8 key[ELEPHANT_MAX_KEY_SIZE]; 1049 1050 memset(key, 0, cc->key_extra_size); 1051 return crypto_skcipher_setkey(elephant->tfm, key, cc->key_extra_size); 1052 } 1053 1054 static const struct crypt_iv_operations crypt_iv_plain_ops = { 1055 .generator = crypt_iv_plain_gen 1056 }; 1057 1058 static const struct crypt_iv_operations crypt_iv_plain64_ops = { 1059 .generator = crypt_iv_plain64_gen 1060 }; 1061 1062 static const struct crypt_iv_operations crypt_iv_plain64be_ops = { 1063 .generator = crypt_iv_plain64be_gen 1064 }; 1065 1066 static const struct crypt_iv_operations crypt_iv_essiv_ops = { 1067 .generator = crypt_iv_essiv_gen 1068 }; 1069 1070 static const struct crypt_iv_operations crypt_iv_benbi_ops = { 1071 .ctr = crypt_iv_benbi_ctr, 1072 .dtr = crypt_iv_benbi_dtr, 1073 .generator = crypt_iv_benbi_gen 1074 }; 1075 1076 static const struct crypt_iv_operations crypt_iv_null_ops = { 1077 .generator = crypt_iv_null_gen 1078 }; 1079 1080 static const struct crypt_iv_operations crypt_iv_lmk_ops = { 1081 .ctr = crypt_iv_lmk_ctr, 1082 .dtr = crypt_iv_lmk_dtr, 1083 .init = crypt_iv_lmk_init, 1084 .wipe = crypt_iv_lmk_wipe, 1085 .generator = crypt_iv_lmk_gen, 1086 .post = crypt_iv_lmk_post 1087 }; 1088 1089 static const struct crypt_iv_operations crypt_iv_tcw_ops = { 1090 .ctr = crypt_iv_tcw_ctr, 1091 .dtr = crypt_iv_tcw_dtr, 1092 .init = crypt_iv_tcw_init, 1093 .wipe = crypt_iv_tcw_wipe, 1094 .generator = crypt_iv_tcw_gen, 1095 .post = crypt_iv_tcw_post 1096 }; 1097 1098 static const struct crypt_iv_operations crypt_iv_random_ops = { 1099 .generator = crypt_iv_random_gen 1100 }; 1101 1102 static const struct crypt_iv_operations crypt_iv_eboiv_ops = { 1103 .ctr = crypt_iv_eboiv_ctr, 1104 .generator = crypt_iv_eboiv_gen 1105 }; 1106 1107 static const struct crypt_iv_operations crypt_iv_elephant_ops = { 1108 .ctr = crypt_iv_elephant_ctr, 1109 .dtr = crypt_iv_elephant_dtr, 1110 .init = crypt_iv_elephant_init, 1111 .wipe = crypt_iv_elephant_wipe, 1112 .generator = crypt_iv_elephant_gen, 1113 .post = crypt_iv_elephant_post 1114 }; 1115 1116 /* 1117 * Integrity extensions 1118 */ 1119 static bool crypt_integrity_aead(struct crypt_config *cc) 1120 { 1121 return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 1122 } 1123 1124 static bool crypt_integrity_hmac(struct crypt_config *cc) 1125 { 1126 return crypt_integrity_aead(cc) && cc->key_mac_size; 1127 } 1128 1129 /* Get sg containing data */ 1130 static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 1131 struct scatterlist *sg) 1132 { 1133 if (unlikely(crypt_integrity_aead(cc))) 1134 return &sg[2]; 1135 1136 return sg; 1137 } 1138 1139 static int dm_crypt_integrity_io_alloc(struct dm_crypt_io *io, struct bio *bio) 1140 { 1141 struct bio_integrity_payload *bip; 1142 unsigned int tag_len; 1143 int ret; 1144 1145 if (!bio_sectors(bio) || !io->cc->on_disk_tag_size) 1146 return 0; 1147 1148 bip = bio_integrity_alloc(bio, GFP_NOIO, 1); 1149 if (IS_ERR(bip)) 1150 return PTR_ERR(bip); 1151 1152 tag_len = io->cc->on_disk_tag_size * (bio_sectors(bio) >> io->cc->sector_shift); 1153 1154 bip->bip_iter.bi_size = tag_len; 1155 bip->bip_iter.bi_sector = io->cc->start + io->sector; 1156 1157 ret = bio_integrity_add_page(bio, virt_to_page(io->integrity_metadata), 1158 tag_len, offset_in_page(io->integrity_metadata)); 1159 if (unlikely(ret != tag_len)) 1160 return -ENOMEM; 1161 1162 return 0; 1163 } 1164 1165 static int crypt_integrity_ctr(struct crypt_config *cc, struct dm_target *ti) 1166 { 1167 #ifdef CONFIG_BLK_DEV_INTEGRITY 1168 struct blk_integrity *bi = blk_get_integrity(cc->dev->bdev->bd_disk); 1169 struct mapped_device *md = dm_table_get_md(ti->table); 1170 1171 /* From now we require underlying device with our integrity profile */ 1172 if (!bi || strcasecmp(bi->profile->name, "DM-DIF-EXT-TAG")) { 1173 ti->error = "Integrity profile not supported."; 1174 return -EINVAL; 1175 } 1176 1177 if (bi->tag_size != cc->on_disk_tag_size || 1178 bi->tuple_size != cc->on_disk_tag_size) { 1179 ti->error = "Integrity profile tag size mismatch."; 1180 return -EINVAL; 1181 } 1182 if (1 << bi->interval_exp != cc->sector_size) { 1183 ti->error = "Integrity profile sector size mismatch."; 1184 return -EINVAL; 1185 } 1186 1187 if (crypt_integrity_aead(cc)) { 1188 cc->integrity_tag_size = cc->on_disk_tag_size - cc->integrity_iv_size; 1189 DMDEBUG("%s: Integrity AEAD, tag size %u, IV size %u.", dm_device_name(md), 1190 cc->integrity_tag_size, cc->integrity_iv_size); 1191 1192 if (crypto_aead_setauthsize(any_tfm_aead(cc), cc->integrity_tag_size)) { 1193 ti->error = "Integrity AEAD auth tag size is not supported."; 1194 return -EINVAL; 1195 } 1196 } else if (cc->integrity_iv_size) 1197 DMDEBUG("%s: Additional per-sector space %u bytes for IV.", dm_device_name(md), 1198 cc->integrity_iv_size); 1199 1200 if ((cc->integrity_tag_size + cc->integrity_iv_size) != bi->tag_size) { 1201 ti->error = "Not enough space for integrity tag in the profile."; 1202 return -EINVAL; 1203 } 1204 1205 return 0; 1206 #else 1207 ti->error = "Integrity profile not supported."; 1208 return -EINVAL; 1209 #endif 1210 } 1211 1212 static void crypt_convert_init(struct crypt_config *cc, 1213 struct convert_context *ctx, 1214 struct bio *bio_out, struct bio *bio_in, 1215 sector_t sector) 1216 { 1217 ctx->bio_in = bio_in; 1218 ctx->bio_out = bio_out; 1219 if (bio_in) 1220 ctx->iter_in = bio_in->bi_iter; 1221 if (bio_out) 1222 ctx->iter_out = bio_out->bi_iter; 1223 ctx->cc_sector = sector + cc->iv_offset; 1224 init_completion(&ctx->restart); 1225 } 1226 1227 static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc, 1228 void *req) 1229 { 1230 return (struct dm_crypt_request *)((char *)req + cc->dmreq_start); 1231 } 1232 1233 static void *req_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq) 1234 { 1235 return (void *)((char *)dmreq - cc->dmreq_start); 1236 } 1237 1238 static u8 *iv_of_dmreq(struct crypt_config *cc, 1239 struct dm_crypt_request *dmreq) 1240 { 1241 if (crypt_integrity_aead(cc)) 1242 return (u8 *)ALIGN((unsigned long)(dmreq + 1), 1243 crypto_aead_alignmask(any_tfm_aead(cc)) + 1); 1244 else 1245 return (u8 *)ALIGN((unsigned long)(dmreq + 1), 1246 crypto_skcipher_alignmask(any_tfm(cc)) + 1); 1247 } 1248 1249 static u8 *org_iv_of_dmreq(struct crypt_config *cc, 1250 struct dm_crypt_request *dmreq) 1251 { 1252 return iv_of_dmreq(cc, dmreq) + cc->iv_size; 1253 } 1254 1255 static __le64 *org_sector_of_dmreq(struct crypt_config *cc, 1256 struct dm_crypt_request *dmreq) 1257 { 1258 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + cc->iv_size; 1259 return (__le64 *) ptr; 1260 } 1261 1262 static unsigned int *org_tag_of_dmreq(struct crypt_config *cc, 1263 struct dm_crypt_request *dmreq) 1264 { 1265 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + 1266 cc->iv_size + sizeof(uint64_t); 1267 return (unsigned int*)ptr; 1268 } 1269 1270 static void *tag_from_dmreq(struct crypt_config *cc, 1271 struct dm_crypt_request *dmreq) 1272 { 1273 struct convert_context *ctx = dmreq->ctx; 1274 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 1275 1276 return &io->integrity_metadata[*org_tag_of_dmreq(cc, dmreq) * 1277 cc->on_disk_tag_size]; 1278 } 1279 1280 static void *iv_tag_from_dmreq(struct crypt_config *cc, 1281 struct dm_crypt_request *dmreq) 1282 { 1283 return tag_from_dmreq(cc, dmreq) + cc->integrity_tag_size; 1284 } 1285 1286 static int crypt_convert_block_aead(struct crypt_config *cc, 1287 struct convert_context *ctx, 1288 struct aead_request *req, 1289 unsigned int tag_offset) 1290 { 1291 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1292 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1293 struct dm_crypt_request *dmreq; 1294 u8 *iv, *org_iv, *tag_iv, *tag; 1295 __le64 *sector; 1296 int r = 0; 1297 1298 BUG_ON(cc->integrity_iv_size && cc->integrity_iv_size != cc->iv_size); 1299 1300 /* Reject unexpected unaligned bio. */ 1301 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1302 return -EIO; 1303 1304 dmreq = dmreq_of_req(cc, req); 1305 dmreq->iv_sector = ctx->cc_sector; 1306 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1307 dmreq->iv_sector >>= cc->sector_shift; 1308 dmreq->ctx = ctx; 1309 1310 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1311 1312 sector = org_sector_of_dmreq(cc, dmreq); 1313 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1314 1315 iv = iv_of_dmreq(cc, dmreq); 1316 org_iv = org_iv_of_dmreq(cc, dmreq); 1317 tag = tag_from_dmreq(cc, dmreq); 1318 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1319 1320 /* AEAD request: 1321 * |----- AAD -------|------ DATA -------|-- AUTH TAG --| 1322 * | (authenticated) | (auth+encryption) | | 1323 * | sector_LE | IV | sector in/out | tag in/out | 1324 */ 1325 sg_init_table(dmreq->sg_in, 4); 1326 sg_set_buf(&dmreq->sg_in[0], sector, sizeof(uint64_t)); 1327 sg_set_buf(&dmreq->sg_in[1], org_iv, cc->iv_size); 1328 sg_set_page(&dmreq->sg_in[2], bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1329 sg_set_buf(&dmreq->sg_in[3], tag, cc->integrity_tag_size); 1330 1331 sg_init_table(dmreq->sg_out, 4); 1332 sg_set_buf(&dmreq->sg_out[0], sector, sizeof(uint64_t)); 1333 sg_set_buf(&dmreq->sg_out[1], org_iv, cc->iv_size); 1334 sg_set_page(&dmreq->sg_out[2], bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1335 sg_set_buf(&dmreq->sg_out[3], tag, cc->integrity_tag_size); 1336 1337 if (cc->iv_gen_ops) { 1338 /* For READs use IV stored in integrity metadata */ 1339 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1340 memcpy(org_iv, tag_iv, cc->iv_size); 1341 } else { 1342 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1343 if (r < 0) 1344 return r; 1345 /* Store generated IV in integrity metadata */ 1346 if (cc->integrity_iv_size) 1347 memcpy(tag_iv, org_iv, cc->iv_size); 1348 } 1349 /* Working copy of IV, to be modified in crypto API */ 1350 memcpy(iv, org_iv, cc->iv_size); 1351 } 1352 1353 aead_request_set_ad(req, sizeof(uint64_t) + cc->iv_size); 1354 if (bio_data_dir(ctx->bio_in) == WRITE) { 1355 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out, 1356 cc->sector_size, iv); 1357 r = crypto_aead_encrypt(req); 1358 if (cc->integrity_tag_size + cc->integrity_iv_size != cc->on_disk_tag_size) 1359 memset(tag + cc->integrity_tag_size + cc->integrity_iv_size, 0, 1360 cc->on_disk_tag_size - (cc->integrity_tag_size + cc->integrity_iv_size)); 1361 } else { 1362 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out, 1363 cc->sector_size + cc->integrity_tag_size, iv); 1364 r = crypto_aead_decrypt(req); 1365 } 1366 1367 if (r == -EBADMSG) { 1368 sector_t s = le64_to_cpu(*sector); 1369 1370 DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu", 1371 ctx->bio_in->bi_bdev, s); 1372 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead", 1373 ctx->bio_in, s, 0); 1374 } 1375 1376 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1377 r = cc->iv_gen_ops->post(cc, org_iv, dmreq); 1378 1379 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1380 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1381 1382 return r; 1383 } 1384 1385 static int crypt_convert_block_skcipher(struct crypt_config *cc, 1386 struct convert_context *ctx, 1387 struct skcipher_request *req, 1388 unsigned int tag_offset) 1389 { 1390 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1391 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1392 struct scatterlist *sg_in, *sg_out; 1393 struct dm_crypt_request *dmreq; 1394 u8 *iv, *org_iv, *tag_iv; 1395 __le64 *sector; 1396 int r = 0; 1397 1398 /* Reject unexpected unaligned bio. */ 1399 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1400 return -EIO; 1401 1402 dmreq = dmreq_of_req(cc, req); 1403 dmreq->iv_sector = ctx->cc_sector; 1404 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1405 dmreq->iv_sector >>= cc->sector_shift; 1406 dmreq->ctx = ctx; 1407 1408 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1409 1410 iv = iv_of_dmreq(cc, dmreq); 1411 org_iv = org_iv_of_dmreq(cc, dmreq); 1412 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1413 1414 sector = org_sector_of_dmreq(cc, dmreq); 1415 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1416 1417 /* For skcipher we use only the first sg item */ 1418 sg_in = &dmreq->sg_in[0]; 1419 sg_out = &dmreq->sg_out[0]; 1420 1421 sg_init_table(sg_in, 1); 1422 sg_set_page(sg_in, bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1423 1424 sg_init_table(sg_out, 1); 1425 sg_set_page(sg_out, bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1426 1427 if (cc->iv_gen_ops) { 1428 /* For READs use IV stored in integrity metadata */ 1429 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1430 memcpy(org_iv, tag_iv, cc->integrity_iv_size); 1431 } else { 1432 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1433 if (r < 0) 1434 return r; 1435 /* Data can be already preprocessed in generator */ 1436 if (test_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags)) 1437 sg_in = sg_out; 1438 /* Store generated IV in integrity metadata */ 1439 if (cc->integrity_iv_size) 1440 memcpy(tag_iv, org_iv, cc->integrity_iv_size); 1441 } 1442 /* Working copy of IV, to be modified in crypto API */ 1443 memcpy(iv, org_iv, cc->iv_size); 1444 } 1445 1446 skcipher_request_set_crypt(req, sg_in, sg_out, cc->sector_size, iv); 1447 1448 if (bio_data_dir(ctx->bio_in) == WRITE) 1449 r = crypto_skcipher_encrypt(req); 1450 else 1451 r = crypto_skcipher_decrypt(req); 1452 1453 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1454 r = cc->iv_gen_ops->post(cc, org_iv, dmreq); 1455 1456 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1457 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1458 1459 return r; 1460 } 1461 1462 static void kcryptd_async_done(struct crypto_async_request *async_req, 1463 int error); 1464 1465 static int crypt_alloc_req_skcipher(struct crypt_config *cc, 1466 struct convert_context *ctx) 1467 { 1468 unsigned int key_index = ctx->cc_sector & (cc->tfms_count - 1); 1469 1470 if (!ctx->r.req) { 1471 ctx->r.req = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1472 if (!ctx->r.req) 1473 return -ENOMEM; 1474 } 1475 1476 skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]); 1477 1478 /* 1479 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1480 * requests if driver request queue is full. 1481 */ 1482 skcipher_request_set_callback(ctx->r.req, 1483 CRYPTO_TFM_REQ_MAY_BACKLOG, 1484 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req)); 1485 1486 return 0; 1487 } 1488 1489 static int crypt_alloc_req_aead(struct crypt_config *cc, 1490 struct convert_context *ctx) 1491 { 1492 if (!ctx->r.req_aead) { 1493 ctx->r.req_aead = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1494 if (!ctx->r.req_aead) 1495 return -ENOMEM; 1496 } 1497 1498 aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]); 1499 1500 /* 1501 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1502 * requests if driver request queue is full. 1503 */ 1504 aead_request_set_callback(ctx->r.req_aead, 1505 CRYPTO_TFM_REQ_MAY_BACKLOG, 1506 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead)); 1507 1508 return 0; 1509 } 1510 1511 static int crypt_alloc_req(struct crypt_config *cc, 1512 struct convert_context *ctx) 1513 { 1514 if (crypt_integrity_aead(cc)) 1515 return crypt_alloc_req_aead(cc, ctx); 1516 else 1517 return crypt_alloc_req_skcipher(cc, ctx); 1518 } 1519 1520 static void crypt_free_req_skcipher(struct crypt_config *cc, 1521 struct skcipher_request *req, struct bio *base_bio) 1522 { 1523 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1524 1525 if ((struct skcipher_request *)(io + 1) != req) 1526 mempool_free(req, &cc->req_pool); 1527 } 1528 1529 static void crypt_free_req_aead(struct crypt_config *cc, 1530 struct aead_request *req, struct bio *base_bio) 1531 { 1532 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1533 1534 if ((struct aead_request *)(io + 1) != req) 1535 mempool_free(req, &cc->req_pool); 1536 } 1537 1538 static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio) 1539 { 1540 if (crypt_integrity_aead(cc)) 1541 crypt_free_req_aead(cc, req, base_bio); 1542 else 1543 crypt_free_req_skcipher(cc, req, base_bio); 1544 } 1545 1546 /* 1547 * Encrypt / decrypt data from one bio to another one (can be the same one) 1548 */ 1549 static blk_status_t crypt_convert(struct crypt_config *cc, 1550 struct convert_context *ctx, bool atomic, bool reset_pending) 1551 { 1552 unsigned int tag_offset = 0; 1553 unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT; 1554 int r; 1555 1556 /* 1557 * if reset_pending is set we are dealing with the bio for the first time, 1558 * else we're continuing to work on the previous bio, so don't mess with 1559 * the cc_pending counter 1560 */ 1561 if (reset_pending) 1562 atomic_set(&ctx->cc_pending, 1); 1563 1564 while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) { 1565 1566 r = crypt_alloc_req(cc, ctx); 1567 if (r) { 1568 complete(&ctx->restart); 1569 return BLK_STS_DEV_RESOURCE; 1570 } 1571 1572 atomic_inc(&ctx->cc_pending); 1573 1574 if (crypt_integrity_aead(cc)) 1575 r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, tag_offset); 1576 else 1577 r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, tag_offset); 1578 1579 switch (r) { 1580 /* 1581 * The request was queued by a crypto driver 1582 * but the driver request queue is full, let's wait. 1583 */ 1584 case -EBUSY: 1585 if (in_interrupt()) { 1586 if (try_wait_for_completion(&ctx->restart)) { 1587 /* 1588 * we don't have to block to wait for completion, 1589 * so proceed 1590 */ 1591 } else { 1592 /* 1593 * we can't wait for completion without blocking 1594 * exit and continue processing in a workqueue 1595 */ 1596 ctx->r.req = NULL; 1597 ctx->cc_sector += sector_step; 1598 tag_offset++; 1599 return BLK_STS_DEV_RESOURCE; 1600 } 1601 } else { 1602 wait_for_completion(&ctx->restart); 1603 } 1604 reinit_completion(&ctx->restart); 1605 fallthrough; 1606 /* 1607 * The request is queued and processed asynchronously, 1608 * completion function kcryptd_async_done() will be called. 1609 */ 1610 case -EINPROGRESS: 1611 ctx->r.req = NULL; 1612 ctx->cc_sector += sector_step; 1613 tag_offset++; 1614 continue; 1615 /* 1616 * The request was already processed (synchronously). 1617 */ 1618 case 0: 1619 atomic_dec(&ctx->cc_pending); 1620 ctx->cc_sector += sector_step; 1621 tag_offset++; 1622 if (!atomic) 1623 cond_resched(); 1624 continue; 1625 /* 1626 * There was a data integrity error. 1627 */ 1628 case -EBADMSG: 1629 atomic_dec(&ctx->cc_pending); 1630 return BLK_STS_PROTECTION; 1631 /* 1632 * There was an error while processing the request. 1633 */ 1634 default: 1635 atomic_dec(&ctx->cc_pending); 1636 return BLK_STS_IOERR; 1637 } 1638 } 1639 1640 return 0; 1641 } 1642 1643 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone); 1644 1645 /* 1646 * Generate a new unfragmented bio with the given size 1647 * This should never violate the device limitations (but only because 1648 * max_segment_size is being constrained to PAGE_SIZE). 1649 * 1650 * This function may be called concurrently. If we allocate from the mempool 1651 * concurrently, there is a possibility of deadlock. For example, if we have 1652 * mempool of 256 pages, two processes, each wanting 256, pages allocate from 1653 * the mempool concurrently, it may deadlock in a situation where both processes 1654 * have allocated 128 pages and the mempool is exhausted. 1655 * 1656 * In order to avoid this scenario we allocate the pages under a mutex. 1657 * 1658 * In order to not degrade performance with excessive locking, we try 1659 * non-blocking allocations without a mutex first but on failure we fallback 1660 * to blocking allocations with a mutex. 1661 */ 1662 static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned int size) 1663 { 1664 struct crypt_config *cc = io->cc; 1665 struct bio *clone; 1666 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; 1667 gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM; 1668 unsigned int i, len, remaining_size; 1669 struct page *page; 1670 1671 retry: 1672 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1673 mutex_lock(&cc->bio_alloc_lock); 1674 1675 clone = bio_alloc_bioset(cc->dev->bdev, nr_iovecs, io->base_bio->bi_opf, 1676 GFP_NOIO, &cc->bs); 1677 clone->bi_private = io; 1678 clone->bi_end_io = crypt_endio; 1679 1680 remaining_size = size; 1681 1682 for (i = 0; i < nr_iovecs; i++) { 1683 page = mempool_alloc(&cc->page_pool, gfp_mask); 1684 if (!page) { 1685 crypt_free_buffer_pages(cc, clone); 1686 bio_put(clone); 1687 gfp_mask |= __GFP_DIRECT_RECLAIM; 1688 goto retry; 1689 } 1690 1691 len = (remaining_size > PAGE_SIZE) ? PAGE_SIZE : remaining_size; 1692 1693 bio_add_page(clone, page, len, 0); 1694 1695 remaining_size -= len; 1696 } 1697 1698 /* Allocate space for integrity tags */ 1699 if (dm_crypt_integrity_io_alloc(io, clone)) { 1700 crypt_free_buffer_pages(cc, clone); 1701 bio_put(clone); 1702 clone = NULL; 1703 } 1704 1705 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1706 mutex_unlock(&cc->bio_alloc_lock); 1707 1708 return clone; 1709 } 1710 1711 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) 1712 { 1713 struct bio_vec *bv; 1714 struct bvec_iter_all iter_all; 1715 1716 bio_for_each_segment_all(bv, clone, iter_all) { 1717 BUG_ON(!bv->bv_page); 1718 mempool_free(bv->bv_page, &cc->page_pool); 1719 } 1720 } 1721 1722 static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc, 1723 struct bio *bio, sector_t sector) 1724 { 1725 io->cc = cc; 1726 io->base_bio = bio; 1727 io->sector = sector; 1728 io->error = 0; 1729 io->ctx.r.req = NULL; 1730 io->integrity_metadata = NULL; 1731 io->integrity_metadata_from_pool = false; 1732 atomic_set(&io->io_pending, 0); 1733 } 1734 1735 static void crypt_inc_pending(struct dm_crypt_io *io) 1736 { 1737 atomic_inc(&io->io_pending); 1738 } 1739 1740 static void kcryptd_io_bio_endio(struct work_struct *work) 1741 { 1742 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 1743 bio_endio(io->base_bio); 1744 } 1745 1746 /* 1747 * One of the bios was finished. Check for completion of 1748 * the whole request and correctly clean up the buffer. 1749 */ 1750 static void crypt_dec_pending(struct dm_crypt_io *io) 1751 { 1752 struct crypt_config *cc = io->cc; 1753 struct bio *base_bio = io->base_bio; 1754 blk_status_t error = io->error; 1755 1756 if (!atomic_dec_and_test(&io->io_pending)) 1757 return; 1758 1759 if (io->ctx.r.req) 1760 crypt_free_req(cc, io->ctx.r.req, base_bio); 1761 1762 if (unlikely(io->integrity_metadata_from_pool)) 1763 mempool_free(io->integrity_metadata, &io->cc->tag_pool); 1764 else 1765 kfree(io->integrity_metadata); 1766 1767 base_bio->bi_status = error; 1768 1769 /* 1770 * If we are running this function from our tasklet, 1771 * we can't call bio_endio() here, because it will call 1772 * clone_endio() from dm.c, which in turn will 1773 * free the current struct dm_crypt_io structure with 1774 * our tasklet. In this case we need to delay bio_endio() 1775 * execution to after the tasklet is done and dequeued. 1776 */ 1777 if (tasklet_trylock(&io->tasklet)) { 1778 tasklet_unlock(&io->tasklet); 1779 bio_endio(base_bio); 1780 return; 1781 } 1782 1783 INIT_WORK(&io->work, kcryptd_io_bio_endio); 1784 queue_work(cc->io_queue, &io->work); 1785 } 1786 1787 /* 1788 * kcryptd/kcryptd_io: 1789 * 1790 * Needed because it would be very unwise to do decryption in an 1791 * interrupt context. 1792 * 1793 * kcryptd performs the actual encryption or decryption. 1794 * 1795 * kcryptd_io performs the IO submission. 1796 * 1797 * They must be separated as otherwise the final stages could be 1798 * starved by new requests which can block in the first stages due 1799 * to memory allocation. 1800 * 1801 * The work is done per CPU global for all dm-crypt instances. 1802 * They should not depend on each other and do not block. 1803 */ 1804 static void crypt_endio(struct bio *clone) 1805 { 1806 struct dm_crypt_io *io = clone->bi_private; 1807 struct crypt_config *cc = io->cc; 1808 unsigned int rw = bio_data_dir(clone); 1809 blk_status_t error; 1810 1811 /* 1812 * free the processed pages 1813 */ 1814 if (rw == WRITE) 1815 crypt_free_buffer_pages(cc, clone); 1816 1817 error = clone->bi_status; 1818 bio_put(clone); 1819 1820 if (rw == READ && !error) { 1821 kcryptd_queue_crypt(io); 1822 return; 1823 } 1824 1825 if (unlikely(error)) 1826 io->error = error; 1827 1828 crypt_dec_pending(io); 1829 } 1830 1831 #define CRYPT_MAP_READ_GFP GFP_NOWAIT 1832 1833 static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp) 1834 { 1835 struct crypt_config *cc = io->cc; 1836 struct bio *clone; 1837 1838 /* 1839 * We need the original biovec array in order to decrypt the whole bio 1840 * data *afterwards* -- thanks to immutable biovecs we don't need to 1841 * worry about the block layer modifying the biovec array; so leverage 1842 * bio_alloc_clone(). 1843 */ 1844 clone = bio_alloc_clone(cc->dev->bdev, io->base_bio, gfp, &cc->bs); 1845 if (!clone) 1846 return 1; 1847 clone->bi_private = io; 1848 clone->bi_end_io = crypt_endio; 1849 1850 crypt_inc_pending(io); 1851 1852 clone->bi_iter.bi_sector = cc->start + io->sector; 1853 1854 if (dm_crypt_integrity_io_alloc(io, clone)) { 1855 crypt_dec_pending(io); 1856 bio_put(clone); 1857 return 1; 1858 } 1859 1860 dm_submit_bio_remap(io->base_bio, clone); 1861 return 0; 1862 } 1863 1864 static void kcryptd_io_read_work(struct work_struct *work) 1865 { 1866 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 1867 1868 crypt_inc_pending(io); 1869 if (kcryptd_io_read(io, GFP_NOIO)) 1870 io->error = BLK_STS_RESOURCE; 1871 crypt_dec_pending(io); 1872 } 1873 1874 static void kcryptd_queue_read(struct dm_crypt_io *io) 1875 { 1876 struct crypt_config *cc = io->cc; 1877 1878 INIT_WORK(&io->work, kcryptd_io_read_work); 1879 queue_work(cc->io_queue, &io->work); 1880 } 1881 1882 static void kcryptd_io_write(struct dm_crypt_io *io) 1883 { 1884 struct bio *clone = io->ctx.bio_out; 1885 1886 dm_submit_bio_remap(io->base_bio, clone); 1887 } 1888 1889 #define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node) 1890 1891 static int dmcrypt_write(void *data) 1892 { 1893 struct crypt_config *cc = data; 1894 struct dm_crypt_io *io; 1895 1896 while (1) { 1897 struct rb_root write_tree; 1898 struct blk_plug plug; 1899 1900 spin_lock_irq(&cc->write_thread_lock); 1901 continue_locked: 1902 1903 if (!RB_EMPTY_ROOT(&cc->write_tree)) 1904 goto pop_from_list; 1905 1906 set_current_state(TASK_INTERRUPTIBLE); 1907 1908 spin_unlock_irq(&cc->write_thread_lock); 1909 1910 if (unlikely(kthread_should_stop())) { 1911 set_current_state(TASK_RUNNING); 1912 break; 1913 } 1914 1915 schedule(); 1916 1917 set_current_state(TASK_RUNNING); 1918 spin_lock_irq(&cc->write_thread_lock); 1919 goto continue_locked; 1920 1921 pop_from_list: 1922 write_tree = cc->write_tree; 1923 cc->write_tree = RB_ROOT; 1924 spin_unlock_irq(&cc->write_thread_lock); 1925 1926 BUG_ON(rb_parent(write_tree.rb_node)); 1927 1928 /* 1929 * Note: we cannot walk the tree here with rb_next because 1930 * the structures may be freed when kcryptd_io_write is called. 1931 */ 1932 blk_start_plug(&plug); 1933 do { 1934 io = crypt_io_from_node(rb_first(&write_tree)); 1935 rb_erase(&io->rb_node, &write_tree); 1936 kcryptd_io_write(io); 1937 } while (!RB_EMPTY_ROOT(&write_tree)); 1938 blk_finish_plug(&plug); 1939 } 1940 return 0; 1941 } 1942 1943 static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async) 1944 { 1945 struct bio *clone = io->ctx.bio_out; 1946 struct crypt_config *cc = io->cc; 1947 unsigned long flags; 1948 sector_t sector; 1949 struct rb_node **rbp, *parent; 1950 1951 if (unlikely(io->error)) { 1952 crypt_free_buffer_pages(cc, clone); 1953 bio_put(clone); 1954 crypt_dec_pending(io); 1955 return; 1956 } 1957 1958 /* crypt_convert should have filled the clone bio */ 1959 BUG_ON(io->ctx.iter_out.bi_size); 1960 1961 clone->bi_iter.bi_sector = cc->start + io->sector; 1962 1963 if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) || 1964 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) { 1965 dm_submit_bio_remap(io->base_bio, clone); 1966 return; 1967 } 1968 1969 spin_lock_irqsave(&cc->write_thread_lock, flags); 1970 if (RB_EMPTY_ROOT(&cc->write_tree)) 1971 wake_up_process(cc->write_thread); 1972 rbp = &cc->write_tree.rb_node; 1973 parent = NULL; 1974 sector = io->sector; 1975 while (*rbp) { 1976 parent = *rbp; 1977 if (sector < crypt_io_from_node(parent)->sector) 1978 rbp = &(*rbp)->rb_left; 1979 else 1980 rbp = &(*rbp)->rb_right; 1981 } 1982 rb_link_node(&io->rb_node, parent, rbp); 1983 rb_insert_color(&io->rb_node, &cc->write_tree); 1984 spin_unlock_irqrestore(&cc->write_thread_lock, flags); 1985 } 1986 1987 static bool kcryptd_crypt_write_inline(struct crypt_config *cc, 1988 struct convert_context *ctx) 1989 1990 { 1991 if (!test_bit(DM_CRYPT_WRITE_INLINE, &cc->flags)) 1992 return false; 1993 1994 /* 1995 * Note: zone append writes (REQ_OP_ZONE_APPEND) do not have ordering 1996 * constraints so they do not need to be issued inline by 1997 * kcryptd_crypt_write_convert(). 1998 */ 1999 switch (bio_op(ctx->bio_in)) { 2000 case REQ_OP_WRITE: 2001 case REQ_OP_WRITE_ZEROES: 2002 return true; 2003 default: 2004 return false; 2005 } 2006 } 2007 2008 static void kcryptd_crypt_write_continue(struct work_struct *work) 2009 { 2010 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2011 struct crypt_config *cc = io->cc; 2012 struct convert_context *ctx = &io->ctx; 2013 int crypt_finished; 2014 sector_t sector = io->sector; 2015 blk_status_t r; 2016 2017 wait_for_completion(&ctx->restart); 2018 reinit_completion(&ctx->restart); 2019 2020 r = crypt_convert(cc, &io->ctx, true, false); 2021 if (r) 2022 io->error = r; 2023 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2024 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2025 /* Wait for completion signaled by kcryptd_async_done() */ 2026 wait_for_completion(&ctx->restart); 2027 crypt_finished = 1; 2028 } 2029 2030 /* Encryption was already finished, submit io now */ 2031 if (crypt_finished) { 2032 kcryptd_crypt_write_io_submit(io, 0); 2033 io->sector = sector; 2034 } 2035 2036 crypt_dec_pending(io); 2037 } 2038 2039 static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) 2040 { 2041 struct crypt_config *cc = io->cc; 2042 struct convert_context *ctx = &io->ctx; 2043 struct bio *clone; 2044 int crypt_finished; 2045 sector_t sector = io->sector; 2046 blk_status_t r; 2047 2048 /* 2049 * Prevent io from disappearing until this function completes. 2050 */ 2051 crypt_inc_pending(io); 2052 crypt_convert_init(cc, ctx, NULL, io->base_bio, sector); 2053 2054 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size); 2055 if (unlikely(!clone)) { 2056 io->error = BLK_STS_IOERR; 2057 goto dec; 2058 } 2059 2060 io->ctx.bio_out = clone; 2061 io->ctx.iter_out = clone->bi_iter; 2062 2063 sector += bio_sectors(clone); 2064 2065 crypt_inc_pending(io); 2066 r = crypt_convert(cc, ctx, 2067 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags), true); 2068 /* 2069 * Crypto API backlogged the request, because its queue was full 2070 * and we're in softirq context, so continue from a workqueue 2071 * (TODO: is it actually possible to be in softirq in the write path?) 2072 */ 2073 if (r == BLK_STS_DEV_RESOURCE) { 2074 INIT_WORK(&io->work, kcryptd_crypt_write_continue); 2075 queue_work(cc->crypt_queue, &io->work); 2076 return; 2077 } 2078 if (r) 2079 io->error = r; 2080 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2081 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2082 /* Wait for completion signaled by kcryptd_async_done() */ 2083 wait_for_completion(&ctx->restart); 2084 crypt_finished = 1; 2085 } 2086 2087 /* Encryption was already finished, submit io now */ 2088 if (crypt_finished) { 2089 kcryptd_crypt_write_io_submit(io, 0); 2090 io->sector = sector; 2091 } 2092 2093 dec: 2094 crypt_dec_pending(io); 2095 } 2096 2097 static void kcryptd_crypt_read_done(struct dm_crypt_io *io) 2098 { 2099 crypt_dec_pending(io); 2100 } 2101 2102 static void kcryptd_crypt_read_continue(struct work_struct *work) 2103 { 2104 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2105 struct crypt_config *cc = io->cc; 2106 blk_status_t r; 2107 2108 wait_for_completion(&io->ctx.restart); 2109 reinit_completion(&io->ctx.restart); 2110 2111 r = crypt_convert(cc, &io->ctx, true, false); 2112 if (r) 2113 io->error = r; 2114 2115 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2116 kcryptd_crypt_read_done(io); 2117 2118 crypt_dec_pending(io); 2119 } 2120 2121 static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) 2122 { 2123 struct crypt_config *cc = io->cc; 2124 blk_status_t r; 2125 2126 crypt_inc_pending(io); 2127 2128 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, 2129 io->sector); 2130 2131 r = crypt_convert(cc, &io->ctx, 2132 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true); 2133 /* 2134 * Crypto API backlogged the request, because its queue was full 2135 * and we're in softirq context, so continue from a workqueue 2136 */ 2137 if (r == BLK_STS_DEV_RESOURCE) { 2138 INIT_WORK(&io->work, kcryptd_crypt_read_continue); 2139 queue_work(cc->crypt_queue, &io->work); 2140 return; 2141 } 2142 if (r) 2143 io->error = r; 2144 2145 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2146 kcryptd_crypt_read_done(io); 2147 2148 crypt_dec_pending(io); 2149 } 2150 2151 static void kcryptd_async_done(struct crypto_async_request *async_req, 2152 int error) 2153 { 2154 struct dm_crypt_request *dmreq = async_req->data; 2155 struct convert_context *ctx = dmreq->ctx; 2156 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 2157 struct crypt_config *cc = io->cc; 2158 2159 /* 2160 * A request from crypto driver backlog is going to be processed now, 2161 * finish the completion and continue in crypt_convert(). 2162 * (Callback will be called for the second time for this request.) 2163 */ 2164 if (error == -EINPROGRESS) { 2165 complete(&ctx->restart); 2166 return; 2167 } 2168 2169 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post) 2170 error = cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq); 2171 2172 if (error == -EBADMSG) { 2173 sector_t s = le64_to_cpu(*org_sector_of_dmreq(cc, dmreq)); 2174 2175 DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu", 2176 ctx->bio_in->bi_bdev, s); 2177 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead", 2178 ctx->bio_in, s, 0); 2179 io->error = BLK_STS_PROTECTION; 2180 } else if (error < 0) 2181 io->error = BLK_STS_IOERR; 2182 2183 crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio); 2184 2185 if (!atomic_dec_and_test(&ctx->cc_pending)) 2186 return; 2187 2188 /* 2189 * The request is fully completed: for inline writes, let 2190 * kcryptd_crypt_write_convert() do the IO submission. 2191 */ 2192 if (bio_data_dir(io->base_bio) == READ) { 2193 kcryptd_crypt_read_done(io); 2194 return; 2195 } 2196 2197 if (kcryptd_crypt_write_inline(cc, ctx)) { 2198 complete(&ctx->restart); 2199 return; 2200 } 2201 2202 kcryptd_crypt_write_io_submit(io, 1); 2203 } 2204 2205 static void kcryptd_crypt(struct work_struct *work) 2206 { 2207 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2208 2209 if (bio_data_dir(io->base_bio) == READ) 2210 kcryptd_crypt_read_convert(io); 2211 else 2212 kcryptd_crypt_write_convert(io); 2213 } 2214 2215 static void kcryptd_crypt_tasklet(unsigned long work) 2216 { 2217 kcryptd_crypt((struct work_struct *)work); 2218 } 2219 2220 static void kcryptd_queue_crypt(struct dm_crypt_io *io) 2221 { 2222 struct crypt_config *cc = io->cc; 2223 2224 if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) || 2225 (bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) { 2226 /* 2227 * in_hardirq(): Crypto API's skcipher_walk_first() refuses to work in hard IRQ context. 2228 * irqs_disabled(): the kernel may run some IO completion from the idle thread, but 2229 * it is being executed with irqs disabled. 2230 */ 2231 if (in_hardirq() || irqs_disabled()) { 2232 tasklet_init(&io->tasklet, kcryptd_crypt_tasklet, (unsigned long)&io->work); 2233 tasklet_schedule(&io->tasklet); 2234 return; 2235 } 2236 2237 kcryptd_crypt(&io->work); 2238 return; 2239 } 2240 2241 INIT_WORK(&io->work, kcryptd_crypt); 2242 queue_work(cc->crypt_queue, &io->work); 2243 } 2244 2245 static void crypt_free_tfms_aead(struct crypt_config *cc) 2246 { 2247 if (!cc->cipher_tfm.tfms_aead) 2248 return; 2249 2250 if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2251 crypto_free_aead(cc->cipher_tfm.tfms_aead[0]); 2252 cc->cipher_tfm.tfms_aead[0] = NULL; 2253 } 2254 2255 kfree(cc->cipher_tfm.tfms_aead); 2256 cc->cipher_tfm.tfms_aead = NULL; 2257 } 2258 2259 static void crypt_free_tfms_skcipher(struct crypt_config *cc) 2260 { 2261 unsigned int i; 2262 2263 if (!cc->cipher_tfm.tfms) 2264 return; 2265 2266 for (i = 0; i < cc->tfms_count; i++) 2267 if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) { 2268 crypto_free_skcipher(cc->cipher_tfm.tfms[i]); 2269 cc->cipher_tfm.tfms[i] = NULL; 2270 } 2271 2272 kfree(cc->cipher_tfm.tfms); 2273 cc->cipher_tfm.tfms = NULL; 2274 } 2275 2276 static void crypt_free_tfms(struct crypt_config *cc) 2277 { 2278 if (crypt_integrity_aead(cc)) 2279 crypt_free_tfms_aead(cc); 2280 else 2281 crypt_free_tfms_skcipher(cc); 2282 } 2283 2284 static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode) 2285 { 2286 unsigned int i; 2287 int err; 2288 2289 cc->cipher_tfm.tfms = kcalloc(cc->tfms_count, 2290 sizeof(struct crypto_skcipher *), 2291 GFP_KERNEL); 2292 if (!cc->cipher_tfm.tfms) 2293 return -ENOMEM; 2294 2295 for (i = 0; i < cc->tfms_count; i++) { 2296 cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0, 2297 CRYPTO_ALG_ALLOCATES_MEMORY); 2298 if (IS_ERR(cc->cipher_tfm.tfms[i])) { 2299 err = PTR_ERR(cc->cipher_tfm.tfms[i]); 2300 crypt_free_tfms(cc); 2301 return err; 2302 } 2303 } 2304 2305 /* 2306 * dm-crypt performance can vary greatly depending on which crypto 2307 * algorithm implementation is used. Help people debug performance 2308 * problems by logging the ->cra_driver_name. 2309 */ 2310 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2311 crypto_skcipher_alg(any_tfm(cc))->base.cra_driver_name); 2312 return 0; 2313 } 2314 2315 static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode) 2316 { 2317 int err; 2318 2319 cc->cipher_tfm.tfms = kmalloc(sizeof(struct crypto_aead *), GFP_KERNEL); 2320 if (!cc->cipher_tfm.tfms) 2321 return -ENOMEM; 2322 2323 cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0, 2324 CRYPTO_ALG_ALLOCATES_MEMORY); 2325 if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2326 err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]); 2327 crypt_free_tfms(cc); 2328 return err; 2329 } 2330 2331 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2332 crypto_aead_alg(any_tfm_aead(cc))->base.cra_driver_name); 2333 return 0; 2334 } 2335 2336 static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode) 2337 { 2338 if (crypt_integrity_aead(cc)) 2339 return crypt_alloc_tfms_aead(cc, ciphermode); 2340 else 2341 return crypt_alloc_tfms_skcipher(cc, ciphermode); 2342 } 2343 2344 static unsigned int crypt_subkey_size(struct crypt_config *cc) 2345 { 2346 return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count); 2347 } 2348 2349 static unsigned int crypt_authenckey_size(struct crypt_config *cc) 2350 { 2351 return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param)); 2352 } 2353 2354 /* 2355 * If AEAD is composed like authenc(hmac(sha256),xts(aes)), 2356 * the key must be for some reason in special format. 2357 * This funcion converts cc->key to this special format. 2358 */ 2359 static void crypt_copy_authenckey(char *p, const void *key, 2360 unsigned int enckeylen, unsigned int authkeylen) 2361 { 2362 struct crypto_authenc_key_param *param; 2363 struct rtattr *rta; 2364 2365 rta = (struct rtattr *)p; 2366 param = RTA_DATA(rta); 2367 param->enckeylen = cpu_to_be32(enckeylen); 2368 rta->rta_len = RTA_LENGTH(sizeof(*param)); 2369 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; 2370 p += RTA_SPACE(sizeof(*param)); 2371 memcpy(p, key + enckeylen, authkeylen); 2372 p += authkeylen; 2373 memcpy(p, key, enckeylen); 2374 } 2375 2376 static int crypt_setkey(struct crypt_config *cc) 2377 { 2378 unsigned int subkey_size; 2379 int err = 0, i, r; 2380 2381 /* Ignore extra keys (which are used for IV etc) */ 2382 subkey_size = crypt_subkey_size(cc); 2383 2384 if (crypt_integrity_hmac(cc)) { 2385 if (subkey_size < cc->key_mac_size) 2386 return -EINVAL; 2387 2388 crypt_copy_authenckey(cc->authenc_key, cc->key, 2389 subkey_size - cc->key_mac_size, 2390 cc->key_mac_size); 2391 } 2392 2393 for (i = 0; i < cc->tfms_count; i++) { 2394 if (crypt_integrity_hmac(cc)) 2395 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2396 cc->authenc_key, crypt_authenckey_size(cc)); 2397 else if (crypt_integrity_aead(cc)) 2398 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2399 cc->key + (i * subkey_size), 2400 subkey_size); 2401 else 2402 r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i], 2403 cc->key + (i * subkey_size), 2404 subkey_size); 2405 if (r) 2406 err = r; 2407 } 2408 2409 if (crypt_integrity_hmac(cc)) 2410 memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc)); 2411 2412 return err; 2413 } 2414 2415 #ifdef CONFIG_KEYS 2416 2417 static bool contains_whitespace(const char *str) 2418 { 2419 while (*str) 2420 if (isspace(*str++)) 2421 return true; 2422 return false; 2423 } 2424 2425 static int set_key_user(struct crypt_config *cc, struct key *key) 2426 { 2427 const struct user_key_payload *ukp; 2428 2429 ukp = user_key_payload_locked(key); 2430 if (!ukp) 2431 return -EKEYREVOKED; 2432 2433 if (cc->key_size != ukp->datalen) 2434 return -EINVAL; 2435 2436 memcpy(cc->key, ukp->data, cc->key_size); 2437 2438 return 0; 2439 } 2440 2441 static int set_key_encrypted(struct crypt_config *cc, struct key *key) 2442 { 2443 const struct encrypted_key_payload *ekp; 2444 2445 ekp = key->payload.data[0]; 2446 if (!ekp) 2447 return -EKEYREVOKED; 2448 2449 if (cc->key_size != ekp->decrypted_datalen) 2450 return -EINVAL; 2451 2452 memcpy(cc->key, ekp->decrypted_data, cc->key_size); 2453 2454 return 0; 2455 } 2456 2457 static int set_key_trusted(struct crypt_config *cc, struct key *key) 2458 { 2459 const struct trusted_key_payload *tkp; 2460 2461 tkp = key->payload.data[0]; 2462 if (!tkp) 2463 return -EKEYREVOKED; 2464 2465 if (cc->key_size != tkp->key_len) 2466 return -EINVAL; 2467 2468 memcpy(cc->key, tkp->key, cc->key_size); 2469 2470 return 0; 2471 } 2472 2473 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2474 { 2475 char *new_key_string, *key_desc; 2476 int ret; 2477 struct key_type *type; 2478 struct key *key; 2479 int (*set_key)(struct crypt_config *cc, struct key *key); 2480 2481 /* 2482 * Reject key_string with whitespace. dm core currently lacks code for 2483 * proper whitespace escaping in arguments on DM_TABLE_STATUS path. 2484 */ 2485 if (contains_whitespace(key_string)) { 2486 DMERR("whitespace chars not allowed in key string"); 2487 return -EINVAL; 2488 } 2489 2490 /* look for next ':' separating key_type from key_description */ 2491 key_desc = strchr(key_string, ':'); 2492 if (!key_desc || key_desc == key_string || !strlen(key_desc + 1)) 2493 return -EINVAL; 2494 2495 if (!strncmp(key_string, "logon:", key_desc - key_string + 1)) { 2496 type = &key_type_logon; 2497 set_key = set_key_user; 2498 } else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) { 2499 type = &key_type_user; 2500 set_key = set_key_user; 2501 } else if (IS_ENABLED(CONFIG_ENCRYPTED_KEYS) && 2502 !strncmp(key_string, "encrypted:", key_desc - key_string + 1)) { 2503 type = &key_type_encrypted; 2504 set_key = set_key_encrypted; 2505 } else if (IS_ENABLED(CONFIG_TRUSTED_KEYS) && 2506 !strncmp(key_string, "trusted:", key_desc - key_string + 1)) { 2507 type = &key_type_trusted; 2508 set_key = set_key_trusted; 2509 } else { 2510 return -EINVAL; 2511 } 2512 2513 new_key_string = kstrdup(key_string, GFP_KERNEL); 2514 if (!new_key_string) 2515 return -ENOMEM; 2516 2517 key = request_key(type, key_desc + 1, NULL); 2518 if (IS_ERR(key)) { 2519 kfree_sensitive(new_key_string); 2520 return PTR_ERR(key); 2521 } 2522 2523 down_read(&key->sem); 2524 2525 ret = set_key(cc, key); 2526 if (ret < 0) { 2527 up_read(&key->sem); 2528 key_put(key); 2529 kfree_sensitive(new_key_string); 2530 return ret; 2531 } 2532 2533 up_read(&key->sem); 2534 key_put(key); 2535 2536 /* clear the flag since following operations may invalidate previously valid key */ 2537 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2538 2539 ret = crypt_setkey(cc); 2540 2541 if (!ret) { 2542 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2543 kfree_sensitive(cc->key_string); 2544 cc->key_string = new_key_string; 2545 } else 2546 kfree_sensitive(new_key_string); 2547 2548 return ret; 2549 } 2550 2551 static int get_key_size(char **key_string) 2552 { 2553 char *colon, dummy; 2554 int ret; 2555 2556 if (*key_string[0] != ':') 2557 return strlen(*key_string) >> 1; 2558 2559 /* look for next ':' in key string */ 2560 colon = strpbrk(*key_string + 1, ":"); 2561 if (!colon) 2562 return -EINVAL; 2563 2564 if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':') 2565 return -EINVAL; 2566 2567 *key_string = colon; 2568 2569 /* remaining key string should be :<logon|user>:<key_desc> */ 2570 2571 return ret; 2572 } 2573 2574 #else 2575 2576 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2577 { 2578 return -EINVAL; 2579 } 2580 2581 static int get_key_size(char **key_string) 2582 { 2583 return (*key_string[0] == ':') ? -EINVAL : (int)(strlen(*key_string) >> 1); 2584 } 2585 2586 #endif /* CONFIG_KEYS */ 2587 2588 static int crypt_set_key(struct crypt_config *cc, char *key) 2589 { 2590 int r = -EINVAL; 2591 int key_string_len = strlen(key); 2592 2593 /* Hyphen (which gives a key_size of zero) means there is no key. */ 2594 if (!cc->key_size && strcmp(key, "-")) 2595 goto out; 2596 2597 /* ':' means the key is in kernel keyring, short-circuit normal key processing */ 2598 if (key[0] == ':') { 2599 r = crypt_set_keyring_key(cc, key + 1); 2600 goto out; 2601 } 2602 2603 /* clear the flag since following operations may invalidate previously valid key */ 2604 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2605 2606 /* wipe references to any kernel keyring key */ 2607 kfree_sensitive(cc->key_string); 2608 cc->key_string = NULL; 2609 2610 /* Decode key from its hex representation. */ 2611 if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0) 2612 goto out; 2613 2614 r = crypt_setkey(cc); 2615 if (!r) 2616 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2617 2618 out: 2619 /* Hex key string not needed after here, so wipe it. */ 2620 memset(key, '0', key_string_len); 2621 2622 return r; 2623 } 2624 2625 static int crypt_wipe_key(struct crypt_config *cc) 2626 { 2627 int r; 2628 2629 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2630 get_random_bytes(&cc->key, cc->key_size); 2631 2632 /* Wipe IV private keys */ 2633 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) { 2634 r = cc->iv_gen_ops->wipe(cc); 2635 if (r) 2636 return r; 2637 } 2638 2639 kfree_sensitive(cc->key_string); 2640 cc->key_string = NULL; 2641 r = crypt_setkey(cc); 2642 memset(&cc->key, 0, cc->key_size * sizeof(u8)); 2643 2644 return r; 2645 } 2646 2647 static void crypt_calculate_pages_per_client(void) 2648 { 2649 unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100; 2650 2651 if (!dm_crypt_clients_n) 2652 return; 2653 2654 pages /= dm_crypt_clients_n; 2655 if (pages < DM_CRYPT_MIN_PAGES_PER_CLIENT) 2656 pages = DM_CRYPT_MIN_PAGES_PER_CLIENT; 2657 dm_crypt_pages_per_client = pages; 2658 } 2659 2660 static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data) 2661 { 2662 struct crypt_config *cc = pool_data; 2663 struct page *page; 2664 2665 /* 2666 * Note, percpu_counter_read_positive() may over (and under) estimate 2667 * the current usage by at most (batch - 1) * num_online_cpus() pages, 2668 * but avoids potential spinlock contention of an exact result. 2669 */ 2670 if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) >= dm_crypt_pages_per_client) && 2671 likely(gfp_mask & __GFP_NORETRY)) 2672 return NULL; 2673 2674 page = alloc_page(gfp_mask); 2675 if (likely(page != NULL)) 2676 percpu_counter_add(&cc->n_allocated_pages, 1); 2677 2678 return page; 2679 } 2680 2681 static void crypt_page_free(void *page, void *pool_data) 2682 { 2683 struct crypt_config *cc = pool_data; 2684 2685 __free_page(page); 2686 percpu_counter_sub(&cc->n_allocated_pages, 1); 2687 } 2688 2689 static void crypt_dtr(struct dm_target *ti) 2690 { 2691 struct crypt_config *cc = ti->private; 2692 2693 ti->private = NULL; 2694 2695 if (!cc) 2696 return; 2697 2698 if (cc->write_thread) 2699 kthread_stop(cc->write_thread); 2700 2701 if (cc->io_queue) 2702 destroy_workqueue(cc->io_queue); 2703 if (cc->crypt_queue) 2704 destroy_workqueue(cc->crypt_queue); 2705 2706 crypt_free_tfms(cc); 2707 2708 bioset_exit(&cc->bs); 2709 2710 mempool_exit(&cc->page_pool); 2711 mempool_exit(&cc->req_pool); 2712 mempool_exit(&cc->tag_pool); 2713 2714 WARN_ON(percpu_counter_sum(&cc->n_allocated_pages) != 0); 2715 percpu_counter_destroy(&cc->n_allocated_pages); 2716 2717 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) 2718 cc->iv_gen_ops->dtr(cc); 2719 2720 if (cc->dev) 2721 dm_put_device(ti, cc->dev); 2722 2723 kfree_sensitive(cc->cipher_string); 2724 kfree_sensitive(cc->key_string); 2725 kfree_sensitive(cc->cipher_auth); 2726 kfree_sensitive(cc->authenc_key); 2727 2728 mutex_destroy(&cc->bio_alloc_lock); 2729 2730 /* Must zero key material before freeing */ 2731 kfree_sensitive(cc); 2732 2733 spin_lock(&dm_crypt_clients_lock); 2734 WARN_ON(!dm_crypt_clients_n); 2735 dm_crypt_clients_n--; 2736 crypt_calculate_pages_per_client(); 2737 spin_unlock(&dm_crypt_clients_lock); 2738 2739 dm_audit_log_dtr(DM_MSG_PREFIX, ti, 1); 2740 } 2741 2742 static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode) 2743 { 2744 struct crypt_config *cc = ti->private; 2745 2746 if (crypt_integrity_aead(cc)) 2747 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2748 else 2749 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2750 2751 if (cc->iv_size) 2752 /* at least a 64 bit sector number should fit in our buffer */ 2753 cc->iv_size = max(cc->iv_size, 2754 (unsigned int)(sizeof(u64) / sizeof(u8))); 2755 else if (ivmode) { 2756 DMWARN("Selected cipher does not support IVs"); 2757 ivmode = NULL; 2758 } 2759 2760 /* Choose ivmode, see comments at iv code. */ 2761 if (ivmode == NULL) 2762 cc->iv_gen_ops = NULL; 2763 else if (strcmp(ivmode, "plain") == 0) 2764 cc->iv_gen_ops = &crypt_iv_plain_ops; 2765 else if (strcmp(ivmode, "plain64") == 0) 2766 cc->iv_gen_ops = &crypt_iv_plain64_ops; 2767 else if (strcmp(ivmode, "plain64be") == 0) 2768 cc->iv_gen_ops = &crypt_iv_plain64be_ops; 2769 else if (strcmp(ivmode, "essiv") == 0) 2770 cc->iv_gen_ops = &crypt_iv_essiv_ops; 2771 else if (strcmp(ivmode, "benbi") == 0) 2772 cc->iv_gen_ops = &crypt_iv_benbi_ops; 2773 else if (strcmp(ivmode, "null") == 0) 2774 cc->iv_gen_ops = &crypt_iv_null_ops; 2775 else if (strcmp(ivmode, "eboiv") == 0) 2776 cc->iv_gen_ops = &crypt_iv_eboiv_ops; 2777 else if (strcmp(ivmode, "elephant") == 0) { 2778 cc->iv_gen_ops = &crypt_iv_elephant_ops; 2779 cc->key_parts = 2; 2780 cc->key_extra_size = cc->key_size / 2; 2781 if (cc->key_extra_size > ELEPHANT_MAX_KEY_SIZE) 2782 return -EINVAL; 2783 set_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags); 2784 } else if (strcmp(ivmode, "lmk") == 0) { 2785 cc->iv_gen_ops = &crypt_iv_lmk_ops; 2786 /* 2787 * Version 2 and 3 is recognised according 2788 * to length of provided multi-key string. 2789 * If present (version 3), last key is used as IV seed. 2790 * All keys (including IV seed) are always the same size. 2791 */ 2792 if (cc->key_size % cc->key_parts) { 2793 cc->key_parts++; 2794 cc->key_extra_size = cc->key_size / cc->key_parts; 2795 } 2796 } else if (strcmp(ivmode, "tcw") == 0) { 2797 cc->iv_gen_ops = &crypt_iv_tcw_ops; 2798 cc->key_parts += 2; /* IV + whitening */ 2799 cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE; 2800 } else if (strcmp(ivmode, "random") == 0) { 2801 cc->iv_gen_ops = &crypt_iv_random_ops; 2802 /* Need storage space in integrity fields. */ 2803 cc->integrity_iv_size = cc->iv_size; 2804 } else { 2805 ti->error = "Invalid IV mode"; 2806 return -EINVAL; 2807 } 2808 2809 return 0; 2810 } 2811 2812 /* 2813 * Workaround to parse HMAC algorithm from AEAD crypto API spec. 2814 * The HMAC is needed to calculate tag size (HMAC digest size). 2815 * This should be probably done by crypto-api calls (once available...) 2816 */ 2817 static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api) 2818 { 2819 char *start, *end, *mac_alg = NULL; 2820 struct crypto_ahash *mac; 2821 2822 if (!strstarts(cipher_api, "authenc(")) 2823 return 0; 2824 2825 start = strchr(cipher_api, '('); 2826 end = strchr(cipher_api, ','); 2827 if (!start || !end || ++start > end) 2828 return -EINVAL; 2829 2830 mac_alg = kzalloc(end - start + 1, GFP_KERNEL); 2831 if (!mac_alg) 2832 return -ENOMEM; 2833 strncpy(mac_alg, start, end - start); 2834 2835 mac = crypto_alloc_ahash(mac_alg, 0, CRYPTO_ALG_ALLOCATES_MEMORY); 2836 kfree(mac_alg); 2837 2838 if (IS_ERR(mac)) 2839 return PTR_ERR(mac); 2840 2841 cc->key_mac_size = crypto_ahash_digestsize(mac); 2842 crypto_free_ahash(mac); 2843 2844 cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL); 2845 if (!cc->authenc_key) 2846 return -ENOMEM; 2847 2848 return 0; 2849 } 2850 2851 static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key, 2852 char **ivmode, char **ivopts) 2853 { 2854 struct crypt_config *cc = ti->private; 2855 char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME]; 2856 int ret = -EINVAL; 2857 2858 cc->tfms_count = 1; 2859 2860 /* 2861 * New format (capi: prefix) 2862 * capi:cipher_api_spec-iv:ivopts 2863 */ 2864 tmp = &cipher_in[strlen("capi:")]; 2865 2866 /* Separate IV options if present, it can contain another '-' in hash name */ 2867 *ivopts = strrchr(tmp, ':'); 2868 if (*ivopts) { 2869 **ivopts = '\0'; 2870 (*ivopts)++; 2871 } 2872 /* Parse IV mode */ 2873 *ivmode = strrchr(tmp, '-'); 2874 if (*ivmode) { 2875 **ivmode = '\0'; 2876 (*ivmode)++; 2877 } 2878 /* The rest is crypto API spec */ 2879 cipher_api = tmp; 2880 2881 /* Alloc AEAD, can be used only in new format. */ 2882 if (crypt_integrity_aead(cc)) { 2883 ret = crypt_ctr_auth_cipher(cc, cipher_api); 2884 if (ret < 0) { 2885 ti->error = "Invalid AEAD cipher spec"; 2886 return -ENOMEM; 2887 } 2888 } 2889 2890 if (*ivmode && !strcmp(*ivmode, "lmk")) 2891 cc->tfms_count = 64; 2892 2893 if (*ivmode && !strcmp(*ivmode, "essiv")) { 2894 if (!*ivopts) { 2895 ti->error = "Digest algorithm missing for ESSIV mode"; 2896 return -EINVAL; 2897 } 2898 ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)", 2899 cipher_api, *ivopts); 2900 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 2901 ti->error = "Cannot allocate cipher string"; 2902 return -ENOMEM; 2903 } 2904 cipher_api = buf; 2905 } 2906 2907 cc->key_parts = cc->tfms_count; 2908 2909 /* Allocate cipher */ 2910 ret = crypt_alloc_tfms(cc, cipher_api); 2911 if (ret < 0) { 2912 ti->error = "Error allocating crypto tfm"; 2913 return ret; 2914 } 2915 2916 if (crypt_integrity_aead(cc)) 2917 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2918 else 2919 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2920 2921 return 0; 2922 } 2923 2924 static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key, 2925 char **ivmode, char **ivopts) 2926 { 2927 struct crypt_config *cc = ti->private; 2928 char *tmp, *cipher, *chainmode, *keycount; 2929 char *cipher_api = NULL; 2930 int ret = -EINVAL; 2931 char dummy; 2932 2933 if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) { 2934 ti->error = "Bad cipher specification"; 2935 return -EINVAL; 2936 } 2937 2938 /* 2939 * Legacy dm-crypt cipher specification 2940 * cipher[:keycount]-mode-iv:ivopts 2941 */ 2942 tmp = cipher_in; 2943 keycount = strsep(&tmp, "-"); 2944 cipher = strsep(&keycount, ":"); 2945 2946 if (!keycount) 2947 cc->tfms_count = 1; 2948 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 || 2949 !is_power_of_2(cc->tfms_count)) { 2950 ti->error = "Bad cipher key count specification"; 2951 return -EINVAL; 2952 } 2953 cc->key_parts = cc->tfms_count; 2954 2955 chainmode = strsep(&tmp, "-"); 2956 *ivmode = strsep(&tmp, ":"); 2957 *ivopts = tmp; 2958 2959 /* 2960 * For compatibility with the original dm-crypt mapping format, if 2961 * only the cipher name is supplied, use cbc-plain. 2962 */ 2963 if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) { 2964 chainmode = "cbc"; 2965 *ivmode = "plain"; 2966 } 2967 2968 if (strcmp(chainmode, "ecb") && !*ivmode) { 2969 ti->error = "IV mechanism required"; 2970 return -EINVAL; 2971 } 2972 2973 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL); 2974 if (!cipher_api) 2975 goto bad_mem; 2976 2977 if (*ivmode && !strcmp(*ivmode, "essiv")) { 2978 if (!*ivopts) { 2979 ti->error = "Digest algorithm missing for ESSIV mode"; 2980 kfree(cipher_api); 2981 return -EINVAL; 2982 } 2983 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 2984 "essiv(%s(%s),%s)", chainmode, cipher, *ivopts); 2985 } else { 2986 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 2987 "%s(%s)", chainmode, cipher); 2988 } 2989 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 2990 kfree(cipher_api); 2991 goto bad_mem; 2992 } 2993 2994 /* Allocate cipher */ 2995 ret = crypt_alloc_tfms(cc, cipher_api); 2996 if (ret < 0) { 2997 ti->error = "Error allocating crypto tfm"; 2998 kfree(cipher_api); 2999 return ret; 3000 } 3001 kfree(cipher_api); 3002 3003 return 0; 3004 bad_mem: 3005 ti->error = "Cannot allocate cipher strings"; 3006 return -ENOMEM; 3007 } 3008 3009 static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key) 3010 { 3011 struct crypt_config *cc = ti->private; 3012 char *ivmode = NULL, *ivopts = NULL; 3013 int ret; 3014 3015 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL); 3016 if (!cc->cipher_string) { 3017 ti->error = "Cannot allocate cipher strings"; 3018 return -ENOMEM; 3019 } 3020 3021 if (strstarts(cipher_in, "capi:")) 3022 ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts); 3023 else 3024 ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts); 3025 if (ret) 3026 return ret; 3027 3028 /* Initialize IV */ 3029 ret = crypt_ctr_ivmode(ti, ivmode); 3030 if (ret < 0) 3031 return ret; 3032 3033 /* Initialize and set key */ 3034 ret = crypt_set_key(cc, key); 3035 if (ret < 0) { 3036 ti->error = "Error decoding and setting key"; 3037 return ret; 3038 } 3039 3040 /* Allocate IV */ 3041 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) { 3042 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts); 3043 if (ret < 0) { 3044 ti->error = "Error creating IV"; 3045 return ret; 3046 } 3047 } 3048 3049 /* Initialize IV (set keys for ESSIV etc) */ 3050 if (cc->iv_gen_ops && cc->iv_gen_ops->init) { 3051 ret = cc->iv_gen_ops->init(cc); 3052 if (ret < 0) { 3053 ti->error = "Error initialising IV"; 3054 return ret; 3055 } 3056 } 3057 3058 /* wipe the kernel key payload copy */ 3059 if (cc->key_string) 3060 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3061 3062 return ret; 3063 } 3064 3065 static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv) 3066 { 3067 struct crypt_config *cc = ti->private; 3068 struct dm_arg_set as; 3069 static const struct dm_arg _args[] = { 3070 {0, 8, "Invalid number of feature args"}, 3071 }; 3072 unsigned int opt_params, val; 3073 const char *opt_string, *sval; 3074 char dummy; 3075 int ret; 3076 3077 /* Optional parameters */ 3078 as.argc = argc; 3079 as.argv = argv; 3080 3081 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error); 3082 if (ret) 3083 return ret; 3084 3085 while (opt_params--) { 3086 opt_string = dm_shift_arg(&as); 3087 if (!opt_string) { 3088 ti->error = "Not enough feature arguments"; 3089 return -EINVAL; 3090 } 3091 3092 if (!strcasecmp(opt_string, "allow_discards")) 3093 ti->num_discard_bios = 1; 3094 3095 else if (!strcasecmp(opt_string, "same_cpu_crypt")) 3096 set_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3097 3098 else if (!strcasecmp(opt_string, "submit_from_crypt_cpus")) 3099 set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3100 else if (!strcasecmp(opt_string, "no_read_workqueue")) 3101 set_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3102 else if (!strcasecmp(opt_string, "no_write_workqueue")) 3103 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3104 else if (sscanf(opt_string, "integrity:%u:", &val) == 1) { 3105 if (val == 0 || val > MAX_TAG_SIZE) { 3106 ti->error = "Invalid integrity arguments"; 3107 return -EINVAL; 3108 } 3109 cc->on_disk_tag_size = val; 3110 sval = strchr(opt_string + strlen("integrity:"), ':') + 1; 3111 if (!strcasecmp(sval, "aead")) { 3112 set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 3113 } else if (strcasecmp(sval, "none")) { 3114 ti->error = "Unknown integrity profile"; 3115 return -EINVAL; 3116 } 3117 3118 cc->cipher_auth = kstrdup(sval, GFP_KERNEL); 3119 if (!cc->cipher_auth) 3120 return -ENOMEM; 3121 } else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) { 3122 if (cc->sector_size < (1 << SECTOR_SHIFT) || 3123 cc->sector_size > 4096 || 3124 (cc->sector_size & (cc->sector_size - 1))) { 3125 ti->error = "Invalid feature value for sector_size"; 3126 return -EINVAL; 3127 } 3128 if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) { 3129 ti->error = "Device size is not multiple of sector_size feature"; 3130 return -EINVAL; 3131 } 3132 cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT; 3133 } else if (!strcasecmp(opt_string, "iv_large_sectors")) 3134 set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3135 else { 3136 ti->error = "Invalid feature arguments"; 3137 return -EINVAL; 3138 } 3139 } 3140 3141 return 0; 3142 } 3143 3144 #ifdef CONFIG_BLK_DEV_ZONED 3145 static int crypt_report_zones(struct dm_target *ti, 3146 struct dm_report_zones_args *args, unsigned int nr_zones) 3147 { 3148 struct crypt_config *cc = ti->private; 3149 3150 return dm_report_zones(cc->dev->bdev, cc->start, 3151 cc->start + dm_target_offset(ti, args->next_sector), 3152 args, nr_zones); 3153 } 3154 #else 3155 #define crypt_report_zones NULL 3156 #endif 3157 3158 /* 3159 * Construct an encryption mapping: 3160 * <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start> 3161 */ 3162 static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) 3163 { 3164 struct crypt_config *cc; 3165 const char *devname = dm_table_device_name(ti->table); 3166 int key_size; 3167 unsigned int align_mask; 3168 unsigned long long tmpll; 3169 int ret; 3170 size_t iv_size_padding, additional_req_size; 3171 char dummy; 3172 3173 if (argc < 5) { 3174 ti->error = "Not enough arguments"; 3175 return -EINVAL; 3176 } 3177 3178 key_size = get_key_size(&argv[1]); 3179 if (key_size < 0) { 3180 ti->error = "Cannot parse key size"; 3181 return -EINVAL; 3182 } 3183 3184 cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL); 3185 if (!cc) { 3186 ti->error = "Cannot allocate encryption context"; 3187 return -ENOMEM; 3188 } 3189 cc->key_size = key_size; 3190 cc->sector_size = (1 << SECTOR_SHIFT); 3191 cc->sector_shift = 0; 3192 3193 ti->private = cc; 3194 3195 spin_lock(&dm_crypt_clients_lock); 3196 dm_crypt_clients_n++; 3197 crypt_calculate_pages_per_client(); 3198 spin_unlock(&dm_crypt_clients_lock); 3199 3200 ret = percpu_counter_init(&cc->n_allocated_pages, 0, GFP_KERNEL); 3201 if (ret < 0) 3202 goto bad; 3203 3204 /* Optional parameters need to be read before cipher constructor */ 3205 if (argc > 5) { 3206 ret = crypt_ctr_optional(ti, argc - 5, &argv[5]); 3207 if (ret) 3208 goto bad; 3209 } 3210 3211 ret = crypt_ctr_cipher(ti, argv[0], argv[1]); 3212 if (ret < 0) 3213 goto bad; 3214 3215 if (crypt_integrity_aead(cc)) { 3216 cc->dmreq_start = sizeof(struct aead_request); 3217 cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc)); 3218 align_mask = crypto_aead_alignmask(any_tfm_aead(cc)); 3219 } else { 3220 cc->dmreq_start = sizeof(struct skcipher_request); 3221 cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc)); 3222 align_mask = crypto_skcipher_alignmask(any_tfm(cc)); 3223 } 3224 cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request)); 3225 3226 if (align_mask < CRYPTO_MINALIGN) { 3227 /* Allocate the padding exactly */ 3228 iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request)) 3229 & align_mask; 3230 } else { 3231 /* 3232 * If the cipher requires greater alignment than kmalloc 3233 * alignment, we don't know the exact position of the 3234 * initialization vector. We must assume worst case. 3235 */ 3236 iv_size_padding = align_mask; 3237 } 3238 3239 /* ...| IV + padding | original IV | original sec. number | bio tag offset | */ 3240 additional_req_size = sizeof(struct dm_crypt_request) + 3241 iv_size_padding + cc->iv_size + 3242 cc->iv_size + 3243 sizeof(uint64_t) + 3244 sizeof(unsigned int); 3245 3246 ret = mempool_init_kmalloc_pool(&cc->req_pool, MIN_IOS, cc->dmreq_start + additional_req_size); 3247 if (ret) { 3248 ti->error = "Cannot allocate crypt request mempool"; 3249 goto bad; 3250 } 3251 3252 cc->per_bio_data_size = ti->per_io_data_size = 3253 ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size, 3254 ARCH_KMALLOC_MINALIGN); 3255 3256 ret = mempool_init(&cc->page_pool, BIO_MAX_VECS, crypt_page_alloc, crypt_page_free, cc); 3257 if (ret) { 3258 ti->error = "Cannot allocate page mempool"; 3259 goto bad; 3260 } 3261 3262 ret = bioset_init(&cc->bs, MIN_IOS, 0, BIOSET_NEED_BVECS); 3263 if (ret) { 3264 ti->error = "Cannot allocate crypt bioset"; 3265 goto bad; 3266 } 3267 3268 mutex_init(&cc->bio_alloc_lock); 3269 3270 ret = -EINVAL; 3271 if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) || 3272 (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) { 3273 ti->error = "Invalid iv_offset sector"; 3274 goto bad; 3275 } 3276 cc->iv_offset = tmpll; 3277 3278 ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev); 3279 if (ret) { 3280 ti->error = "Device lookup failed"; 3281 goto bad; 3282 } 3283 3284 ret = -EINVAL; 3285 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) { 3286 ti->error = "Invalid device sector"; 3287 goto bad; 3288 } 3289 cc->start = tmpll; 3290 3291 if (bdev_is_zoned(cc->dev->bdev)) { 3292 /* 3293 * For zoned block devices, we need to preserve the issuer write 3294 * ordering. To do so, disable write workqueues and force inline 3295 * encryption completion. 3296 */ 3297 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3298 set_bit(DM_CRYPT_WRITE_INLINE, &cc->flags); 3299 3300 /* 3301 * All zone append writes to a zone of a zoned block device will 3302 * have the same BIO sector, the start of the zone. When the 3303 * cypher IV mode uses sector values, all data targeting a 3304 * zone will be encrypted using the first sector numbers of the 3305 * zone. This will not result in write errors but will 3306 * cause most reads to fail as reads will use the sector values 3307 * for the actual data locations, resulting in IV mismatch. 3308 * To avoid this problem, ask DM core to emulate zone append 3309 * operations with regular writes. 3310 */ 3311 DMDEBUG("Zone append operations will be emulated"); 3312 ti->emulate_zone_append = true; 3313 } 3314 3315 if (crypt_integrity_aead(cc) || cc->integrity_iv_size) { 3316 ret = crypt_integrity_ctr(cc, ti); 3317 if (ret) 3318 goto bad; 3319 3320 cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->on_disk_tag_size; 3321 if (!cc->tag_pool_max_sectors) 3322 cc->tag_pool_max_sectors = 1; 3323 3324 ret = mempool_init_kmalloc_pool(&cc->tag_pool, MIN_IOS, 3325 cc->tag_pool_max_sectors * cc->on_disk_tag_size); 3326 if (ret) { 3327 ti->error = "Cannot allocate integrity tags mempool"; 3328 goto bad; 3329 } 3330 3331 cc->tag_pool_max_sectors <<= cc->sector_shift; 3332 } 3333 3334 ret = -ENOMEM; 3335 cc->io_queue = alloc_workqueue("kcryptd_io/%s", WQ_MEM_RECLAIM, 1, devname); 3336 if (!cc->io_queue) { 3337 ti->error = "Couldn't create kcryptd io queue"; 3338 goto bad; 3339 } 3340 3341 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3342 cc->crypt_queue = alloc_workqueue("kcryptd/%s", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 3343 1, devname); 3344 else 3345 cc->crypt_queue = alloc_workqueue("kcryptd/%s", 3346 WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND, 3347 num_online_cpus(), devname); 3348 if (!cc->crypt_queue) { 3349 ti->error = "Couldn't create kcryptd queue"; 3350 goto bad; 3351 } 3352 3353 spin_lock_init(&cc->write_thread_lock); 3354 cc->write_tree = RB_ROOT; 3355 3356 cc->write_thread = kthread_run(dmcrypt_write, cc, "dmcrypt_write/%s", devname); 3357 if (IS_ERR(cc->write_thread)) { 3358 ret = PTR_ERR(cc->write_thread); 3359 cc->write_thread = NULL; 3360 ti->error = "Couldn't spawn write thread"; 3361 goto bad; 3362 } 3363 3364 ti->num_flush_bios = 1; 3365 ti->limit_swap_bios = true; 3366 ti->accounts_remapped_io = true; 3367 3368 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 1); 3369 return 0; 3370 3371 bad: 3372 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 0); 3373 crypt_dtr(ti); 3374 return ret; 3375 } 3376 3377 static int crypt_map(struct dm_target *ti, struct bio *bio) 3378 { 3379 struct dm_crypt_io *io; 3380 struct crypt_config *cc = ti->private; 3381 3382 /* 3383 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues. 3384 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight 3385 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters 3386 */ 3387 if (unlikely(bio->bi_opf & REQ_PREFLUSH || 3388 bio_op(bio) == REQ_OP_DISCARD)) { 3389 bio_set_dev(bio, cc->dev->bdev); 3390 if (bio_sectors(bio)) 3391 bio->bi_iter.bi_sector = cc->start + 3392 dm_target_offset(ti, bio->bi_iter.bi_sector); 3393 return DM_MAPIO_REMAPPED; 3394 } 3395 3396 /* 3397 * Check if bio is too large, split as needed. 3398 */ 3399 if (unlikely(bio->bi_iter.bi_size > (BIO_MAX_VECS << PAGE_SHIFT)) && 3400 (bio_data_dir(bio) == WRITE || cc->on_disk_tag_size)) 3401 dm_accept_partial_bio(bio, ((BIO_MAX_VECS << PAGE_SHIFT) >> SECTOR_SHIFT)); 3402 3403 /* 3404 * Ensure that bio is a multiple of internal sector encryption size 3405 * and is aligned to this size as defined in IO hints. 3406 */ 3407 if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0)) 3408 return DM_MAPIO_KILL; 3409 3410 if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1))) 3411 return DM_MAPIO_KILL; 3412 3413 io = dm_per_bio_data(bio, cc->per_bio_data_size); 3414 crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector)); 3415 3416 if (cc->on_disk_tag_size) { 3417 unsigned int tag_len = cc->on_disk_tag_size * (bio_sectors(bio) >> cc->sector_shift); 3418 3419 if (unlikely(tag_len > KMALLOC_MAX_SIZE) || 3420 unlikely(!(io->integrity_metadata = kmalloc(tag_len, 3421 GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN)))) { 3422 if (bio_sectors(bio) > cc->tag_pool_max_sectors) 3423 dm_accept_partial_bio(bio, cc->tag_pool_max_sectors); 3424 io->integrity_metadata = mempool_alloc(&cc->tag_pool, GFP_NOIO); 3425 io->integrity_metadata_from_pool = true; 3426 } 3427 } 3428 3429 if (crypt_integrity_aead(cc)) 3430 io->ctx.r.req_aead = (struct aead_request *)(io + 1); 3431 else 3432 io->ctx.r.req = (struct skcipher_request *)(io + 1); 3433 3434 if (bio_data_dir(io->base_bio) == READ) { 3435 if (kcryptd_io_read(io, CRYPT_MAP_READ_GFP)) 3436 kcryptd_queue_read(io); 3437 } else 3438 kcryptd_queue_crypt(io); 3439 3440 return DM_MAPIO_SUBMITTED; 3441 } 3442 3443 static char hex2asc(unsigned char c) 3444 { 3445 return c + '0' + ((unsigned int)(9 - c) >> 4 & 0x27); 3446 } 3447 3448 static void crypt_status(struct dm_target *ti, status_type_t type, 3449 unsigned int status_flags, char *result, unsigned int maxlen) 3450 { 3451 struct crypt_config *cc = ti->private; 3452 unsigned int i, sz = 0; 3453 int num_feature_args = 0; 3454 3455 switch (type) { 3456 case STATUSTYPE_INFO: 3457 result[0] = '\0'; 3458 break; 3459 3460 case STATUSTYPE_TABLE: 3461 DMEMIT("%s ", cc->cipher_string); 3462 3463 if (cc->key_size > 0) { 3464 if (cc->key_string) 3465 DMEMIT(":%u:%s", cc->key_size, cc->key_string); 3466 else { 3467 for (i = 0; i < cc->key_size; i++) { 3468 DMEMIT("%c%c", hex2asc(cc->key[i] >> 4), 3469 hex2asc(cc->key[i] & 0xf)); 3470 } 3471 } 3472 } else 3473 DMEMIT("-"); 3474 3475 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, 3476 cc->dev->name, (unsigned long long)cc->start); 3477 3478 num_feature_args += !!ti->num_discard_bios; 3479 num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3480 num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3481 num_feature_args += test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3482 num_feature_args += test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3483 num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT); 3484 num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3485 if (cc->on_disk_tag_size) 3486 num_feature_args++; 3487 if (num_feature_args) { 3488 DMEMIT(" %d", num_feature_args); 3489 if (ti->num_discard_bios) 3490 DMEMIT(" allow_discards"); 3491 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3492 DMEMIT(" same_cpu_crypt"); 3493 if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) 3494 DMEMIT(" submit_from_crypt_cpus"); 3495 if (test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) 3496 DMEMIT(" no_read_workqueue"); 3497 if (test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) 3498 DMEMIT(" no_write_workqueue"); 3499 if (cc->on_disk_tag_size) 3500 DMEMIT(" integrity:%u:%s", cc->on_disk_tag_size, cc->cipher_auth); 3501 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3502 DMEMIT(" sector_size:%d", cc->sector_size); 3503 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 3504 DMEMIT(" iv_large_sectors"); 3505 } 3506 break; 3507 3508 case STATUSTYPE_IMA: 3509 DMEMIT_TARGET_NAME_VERSION(ti->type); 3510 DMEMIT(",allow_discards=%c", ti->num_discard_bios ? 'y' : 'n'); 3511 DMEMIT(",same_cpu_crypt=%c", test_bit(DM_CRYPT_SAME_CPU, &cc->flags) ? 'y' : 'n'); 3512 DMEMIT(",submit_from_crypt_cpus=%c", test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags) ? 3513 'y' : 'n'); 3514 DMEMIT(",no_read_workqueue=%c", test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags) ? 3515 'y' : 'n'); 3516 DMEMIT(",no_write_workqueue=%c", test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags) ? 3517 'y' : 'n'); 3518 DMEMIT(",iv_large_sectors=%c", test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags) ? 3519 'y' : 'n'); 3520 3521 if (cc->on_disk_tag_size) 3522 DMEMIT(",integrity_tag_size=%u,cipher_auth=%s", 3523 cc->on_disk_tag_size, cc->cipher_auth); 3524 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3525 DMEMIT(",sector_size=%d", cc->sector_size); 3526 if (cc->cipher_string) 3527 DMEMIT(",cipher_string=%s", cc->cipher_string); 3528 3529 DMEMIT(",key_size=%u", cc->key_size); 3530 DMEMIT(",key_parts=%u", cc->key_parts); 3531 DMEMIT(",key_extra_size=%u", cc->key_extra_size); 3532 DMEMIT(",key_mac_size=%u", cc->key_mac_size); 3533 DMEMIT(";"); 3534 break; 3535 } 3536 } 3537 3538 static void crypt_postsuspend(struct dm_target *ti) 3539 { 3540 struct crypt_config *cc = ti->private; 3541 3542 set_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3543 } 3544 3545 static int crypt_preresume(struct dm_target *ti) 3546 { 3547 struct crypt_config *cc = ti->private; 3548 3549 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { 3550 DMERR("aborting resume - crypt key is not set."); 3551 return -EAGAIN; 3552 } 3553 3554 return 0; 3555 } 3556 3557 static void crypt_resume(struct dm_target *ti) 3558 { 3559 struct crypt_config *cc = ti->private; 3560 3561 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3562 } 3563 3564 /* Message interface 3565 * key set <key> 3566 * key wipe 3567 */ 3568 static int crypt_message(struct dm_target *ti, unsigned int argc, char **argv, 3569 char *result, unsigned int maxlen) 3570 { 3571 struct crypt_config *cc = ti->private; 3572 int key_size, ret = -EINVAL; 3573 3574 if (argc < 2) 3575 goto error; 3576 3577 if (!strcasecmp(argv[0], "key")) { 3578 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { 3579 DMWARN("not suspended during key manipulation."); 3580 return -EINVAL; 3581 } 3582 if (argc == 3 && !strcasecmp(argv[1], "set")) { 3583 /* The key size may not be changed. */ 3584 key_size = get_key_size(&argv[2]); 3585 if (key_size < 0 || cc->key_size != key_size) { 3586 memset(argv[2], '0', strlen(argv[2])); 3587 return -EINVAL; 3588 } 3589 3590 ret = crypt_set_key(cc, argv[2]); 3591 if (ret) 3592 return ret; 3593 if (cc->iv_gen_ops && cc->iv_gen_ops->init) 3594 ret = cc->iv_gen_ops->init(cc); 3595 /* wipe the kernel key payload copy */ 3596 if (cc->key_string) 3597 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3598 return ret; 3599 } 3600 if (argc == 2 && !strcasecmp(argv[1], "wipe")) 3601 return crypt_wipe_key(cc); 3602 } 3603 3604 error: 3605 DMWARN("unrecognised message received."); 3606 return -EINVAL; 3607 } 3608 3609 static int crypt_iterate_devices(struct dm_target *ti, 3610 iterate_devices_callout_fn fn, void *data) 3611 { 3612 struct crypt_config *cc = ti->private; 3613 3614 return fn(ti, cc->dev, cc->start, ti->len, data); 3615 } 3616 3617 static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits) 3618 { 3619 struct crypt_config *cc = ti->private; 3620 3621 /* 3622 * Unfortunate constraint that is required to avoid the potential 3623 * for exceeding underlying device's max_segments limits -- due to 3624 * crypt_alloc_buffer() possibly allocating pages for the encryption 3625 * bio that are not as physically contiguous as the original bio. 3626 */ 3627 limits->max_segment_size = PAGE_SIZE; 3628 3629 limits->logical_block_size = 3630 max_t(unsigned int, limits->logical_block_size, cc->sector_size); 3631 limits->physical_block_size = 3632 max_t(unsigned int, limits->physical_block_size, cc->sector_size); 3633 limits->io_min = max_t(unsigned int, limits->io_min, cc->sector_size); 3634 limits->dma_alignment = limits->logical_block_size - 1; 3635 } 3636 3637 static struct target_type crypt_target = { 3638 .name = "crypt", 3639 .version = {1, 24, 0}, 3640 .module = THIS_MODULE, 3641 .ctr = crypt_ctr, 3642 .dtr = crypt_dtr, 3643 .features = DM_TARGET_ZONED_HM, 3644 .report_zones = crypt_report_zones, 3645 .map = crypt_map, 3646 .status = crypt_status, 3647 .postsuspend = crypt_postsuspend, 3648 .preresume = crypt_preresume, 3649 .resume = crypt_resume, 3650 .message = crypt_message, 3651 .iterate_devices = crypt_iterate_devices, 3652 .io_hints = crypt_io_hints, 3653 }; 3654 3655 static int __init dm_crypt_init(void) 3656 { 3657 int r; 3658 3659 r = dm_register_target(&crypt_target); 3660 if (r < 0) 3661 DMERR("register failed %d", r); 3662 3663 return r; 3664 } 3665 3666 static void __exit dm_crypt_exit(void) 3667 { 3668 dm_unregister_target(&crypt_target); 3669 } 3670 3671 module_init(dm_crypt_init); 3672 module_exit(dm_crypt_exit); 3673 3674 MODULE_AUTHOR("Jana Saout <jana@saout.de>"); 3675 MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); 3676 MODULE_LICENSE("GPL"); 3677