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/skcipher.h> 35 #include <crypto/aead.h> 36 #include <crypto/authenc.h> 37 #include <crypto/utils.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 bvec_iter iter_in; 57 struct bio *bio_out; 58 struct bvec_iter iter_out; 59 atomic_t cc_pending; 60 u64 cc_sector; 61 union { 62 struct skcipher_request *req; 63 struct aead_request *req_aead; 64 } r; 65 bool aead_recheck; 66 bool aead_failed; 67 68 }; 69 70 /* 71 * per bio private data 72 */ 73 struct dm_crypt_io { 74 struct crypt_config *cc; 75 struct bio *base_bio; 76 u8 *integrity_metadata; 77 bool integrity_metadata_from_pool:1; 78 79 struct work_struct work; 80 81 struct convert_context ctx; 82 83 atomic_t io_pending; 84 blk_status_t error; 85 sector_t sector; 86 87 struct bvec_iter saved_bi_iter; 88 89 struct rb_node rb_node; 90 } CRYPTO_MINALIGN_ATTR; 91 92 struct dm_crypt_request { 93 struct convert_context *ctx; 94 struct scatterlist sg_in[4]; 95 struct scatterlist sg_out[4]; 96 u64 iv_sector; 97 }; 98 99 struct crypt_config; 100 101 struct crypt_iv_operations { 102 int (*ctr)(struct crypt_config *cc, struct dm_target *ti, 103 const char *opts); 104 void (*dtr)(struct crypt_config *cc); 105 int (*init)(struct crypt_config *cc); 106 int (*wipe)(struct crypt_config *cc); 107 int (*generator)(struct crypt_config *cc, u8 *iv, 108 struct dm_crypt_request *dmreq); 109 int (*post)(struct crypt_config *cc, u8 *iv, 110 struct dm_crypt_request *dmreq); 111 }; 112 113 struct iv_benbi_private { 114 int shift; 115 }; 116 117 #define LMK_SEED_SIZE 64 /* hash + 0 */ 118 struct iv_lmk_private { 119 struct crypto_shash *hash_tfm; 120 u8 *seed; 121 }; 122 123 #define TCW_WHITENING_SIZE 16 124 struct iv_tcw_private { 125 struct crypto_shash *crc32_tfm; 126 u8 *iv_seed; 127 u8 *whitening; 128 }; 129 130 #define ELEPHANT_MAX_KEY_SIZE 32 131 struct iv_elephant_private { 132 struct crypto_skcipher *tfm; 133 }; 134 135 /* 136 * Crypt: maps a linear range of a block device 137 * and encrypts / decrypts at the same time. 138 */ 139 enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID, 140 DM_CRYPT_SAME_CPU, DM_CRYPT_NO_OFFLOAD, 141 DM_CRYPT_NO_READ_WORKQUEUE, DM_CRYPT_NO_WRITE_WORKQUEUE, 142 DM_CRYPT_WRITE_INLINE }; 143 144 enum cipher_flags { 145 CRYPT_MODE_INTEGRITY_AEAD, /* Use authenticated mode for cipher */ 146 CRYPT_IV_LARGE_SECTORS, /* Calculate IV from sector_size, not 512B sectors */ 147 CRYPT_ENCRYPT_PREPROCESS, /* Must preprocess data for encryption (elephant) */ 148 }; 149 150 /* 151 * The fields in here must be read only after initialization. 152 */ 153 struct crypt_config { 154 struct dm_dev *dev; 155 sector_t start; 156 157 struct percpu_counter n_allocated_pages; 158 159 struct workqueue_struct *io_queue; 160 struct workqueue_struct *crypt_queue; 161 162 spinlock_t write_thread_lock; 163 struct task_struct *write_thread; 164 struct rb_root write_tree; 165 166 char *cipher_string; 167 char *cipher_auth; 168 char *key_string; 169 170 const struct crypt_iv_operations *iv_gen_ops; 171 union { 172 struct iv_benbi_private benbi; 173 struct iv_lmk_private lmk; 174 struct iv_tcw_private tcw; 175 struct iv_elephant_private elephant; 176 } iv_gen_private; 177 u64 iv_offset; 178 unsigned int iv_size; 179 unsigned short sector_size; 180 unsigned char sector_shift; 181 182 union { 183 struct crypto_skcipher **tfms; 184 struct crypto_aead **tfms_aead; 185 } cipher_tfm; 186 unsigned int tfms_count; 187 unsigned long cipher_flags; 188 189 /* 190 * Layout of each crypto request: 191 * 192 * struct skcipher_request 193 * context 194 * padding 195 * struct dm_crypt_request 196 * padding 197 * IV 198 * 199 * The padding is added so that dm_crypt_request and the IV are 200 * correctly aligned. 201 */ 202 unsigned int dmreq_start; 203 204 unsigned int per_bio_data_size; 205 206 unsigned long flags; 207 unsigned int key_size; 208 unsigned int key_parts; /* independent parts in key buffer */ 209 unsigned int key_extra_size; /* additional keys length */ 210 unsigned int key_mac_size; /* MAC key size for authenc(...) */ 211 212 unsigned int integrity_tag_size; 213 unsigned int integrity_iv_size; 214 unsigned int on_disk_tag_size; 215 216 /* 217 * pool for per bio private data, crypto requests, 218 * encryption requeusts/buffer pages and integrity tags 219 */ 220 unsigned int tag_pool_max_sectors; 221 mempool_t tag_pool; 222 mempool_t req_pool; 223 mempool_t page_pool; 224 225 struct bio_set bs; 226 struct mutex bio_alloc_lock; 227 228 u8 *authenc_key; /* space for keys in authenc() format (if used) */ 229 u8 key[]; 230 }; 231 232 #define MIN_IOS 64 233 #define MAX_TAG_SIZE 480 234 #define POOL_ENTRY_SIZE 512 235 236 static DEFINE_SPINLOCK(dm_crypt_clients_lock); 237 static unsigned int dm_crypt_clients_n; 238 static volatile unsigned long dm_crypt_pages_per_client; 239 #define DM_CRYPT_MEMORY_PERCENT 2 240 #define DM_CRYPT_MIN_PAGES_PER_CLIENT (BIO_MAX_VECS * 16) 241 242 static void crypt_endio(struct bio *clone); 243 static void kcryptd_queue_crypt(struct dm_crypt_io *io); 244 static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 245 struct scatterlist *sg); 246 247 static bool crypt_integrity_aead(struct crypt_config *cc); 248 249 /* 250 * Use this to access cipher attributes that are independent of the key. 251 */ 252 static struct crypto_skcipher *any_tfm(struct crypt_config *cc) 253 { 254 return cc->cipher_tfm.tfms[0]; 255 } 256 257 static struct crypto_aead *any_tfm_aead(struct crypt_config *cc) 258 { 259 return cc->cipher_tfm.tfms_aead[0]; 260 } 261 262 /* 263 * Different IV generation algorithms: 264 * 265 * plain: the initial vector is the 32-bit little-endian version of the sector 266 * number, padded with zeros if necessary. 267 * 268 * plain64: the initial vector is the 64-bit little-endian version of the sector 269 * number, padded with zeros if necessary. 270 * 271 * plain64be: the initial vector is the 64-bit big-endian version of the sector 272 * number, padded with zeros if necessary. 273 * 274 * essiv: "encrypted sector|salt initial vector", the sector number is 275 * encrypted with the bulk cipher using a salt as key. The salt 276 * should be derived from the bulk cipher's key via hashing. 277 * 278 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 279 * (needed for LRW-32-AES and possible other narrow block modes) 280 * 281 * null: the initial vector is always zero. Provides compatibility with 282 * obsolete loop_fish2 devices. Do not use for new devices. 283 * 284 * lmk: Compatible implementation of the block chaining mode used 285 * by the Loop-AES block device encryption system 286 * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/ 287 * It operates on full 512 byte sectors and uses CBC 288 * with an IV derived from the sector number, the data and 289 * optionally extra IV seed. 290 * This means that after decryption the first block 291 * of sector must be tweaked according to decrypted data. 292 * Loop-AES can use three encryption schemes: 293 * version 1: is plain aes-cbc mode 294 * version 2: uses 64 multikey scheme with lmk IV generator 295 * version 3: the same as version 2 with additional IV seed 296 * (it uses 65 keys, last key is used as IV seed) 297 * 298 * tcw: Compatible implementation of the block chaining mode used 299 * by the TrueCrypt device encryption system (prior to version 4.1). 300 * For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat 301 * It operates on full 512 byte sectors and uses CBC 302 * with an IV derived from initial key and the sector number. 303 * In addition, whitening value is applied on every sector, whitening 304 * is calculated from initial key, sector number and mixed using CRC32. 305 * Note that this encryption scheme is vulnerable to watermarking attacks 306 * and should be used for old compatible containers access only. 307 * 308 * eboiv: Encrypted byte-offset IV (used in Bitlocker in CBC mode) 309 * The IV is encrypted little-endian byte-offset (with the same key 310 * and cipher as the volume). 311 * 312 * elephant: The extended version of eboiv with additional Elephant diffuser 313 * used with Bitlocker CBC mode. 314 * This mode was used in older Windows systems 315 * https://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf 316 */ 317 318 static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, 319 struct dm_crypt_request *dmreq) 320 { 321 memset(iv, 0, cc->iv_size); 322 *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff); 323 324 return 0; 325 } 326 327 static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv, 328 struct dm_crypt_request *dmreq) 329 { 330 memset(iv, 0, cc->iv_size); 331 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 332 333 return 0; 334 } 335 336 static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv, 337 struct dm_crypt_request *dmreq) 338 { 339 memset(iv, 0, cc->iv_size); 340 /* iv_size is at least of size u64; usually it is 16 bytes */ 341 *(__be64 *)&iv[cc->iv_size - sizeof(u64)] = cpu_to_be64(dmreq->iv_sector); 342 343 return 0; 344 } 345 346 static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, 347 struct dm_crypt_request *dmreq) 348 { 349 /* 350 * ESSIV encryption of the IV is now handled by the crypto API, 351 * so just pass the plain sector number here. 352 */ 353 memset(iv, 0, cc->iv_size); 354 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 355 356 return 0; 357 } 358 359 static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, 360 const char *opts) 361 { 362 unsigned int bs; 363 int log; 364 365 if (crypt_integrity_aead(cc)) 366 bs = crypto_aead_blocksize(any_tfm_aead(cc)); 367 else 368 bs = crypto_skcipher_blocksize(any_tfm(cc)); 369 log = ilog2(bs); 370 371 /* 372 * We need to calculate how far we must shift the sector count 373 * to get the cipher block count, we use this shift in _gen. 374 */ 375 if (1 << log != bs) { 376 ti->error = "cypher blocksize is not a power of 2"; 377 return -EINVAL; 378 } 379 380 if (log > 9) { 381 ti->error = "cypher blocksize is > 512"; 382 return -EINVAL; 383 } 384 385 cc->iv_gen_private.benbi.shift = 9 - log; 386 387 return 0; 388 } 389 390 static void crypt_iv_benbi_dtr(struct crypt_config *cc) 391 { 392 } 393 394 static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, 395 struct dm_crypt_request *dmreq) 396 { 397 __be64 val; 398 399 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ 400 401 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1); 402 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); 403 404 return 0; 405 } 406 407 static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, 408 struct dm_crypt_request *dmreq) 409 { 410 memset(iv, 0, cc->iv_size); 411 412 return 0; 413 } 414 415 static void crypt_iv_lmk_dtr(struct crypt_config *cc) 416 { 417 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 418 419 if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm)) 420 crypto_free_shash(lmk->hash_tfm); 421 lmk->hash_tfm = NULL; 422 423 kfree_sensitive(lmk->seed); 424 lmk->seed = NULL; 425 } 426 427 static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti, 428 const char *opts) 429 { 430 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 431 432 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 433 ti->error = "Unsupported sector size for LMK"; 434 return -EINVAL; 435 } 436 437 lmk->hash_tfm = crypto_alloc_shash("md5", 0, 438 CRYPTO_ALG_ALLOCATES_MEMORY); 439 if (IS_ERR(lmk->hash_tfm)) { 440 ti->error = "Error initializing LMK hash"; 441 return PTR_ERR(lmk->hash_tfm); 442 } 443 444 /* No seed in LMK version 2 */ 445 if (cc->key_parts == cc->tfms_count) { 446 lmk->seed = NULL; 447 return 0; 448 } 449 450 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL); 451 if (!lmk->seed) { 452 crypt_iv_lmk_dtr(cc); 453 ti->error = "Error kmallocing seed storage in LMK"; 454 return -ENOMEM; 455 } 456 457 return 0; 458 } 459 460 static int crypt_iv_lmk_init(struct crypt_config *cc) 461 { 462 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 463 int subkey_size = cc->key_size / cc->key_parts; 464 465 /* LMK seed is on the position of LMK_KEYS + 1 key */ 466 if (lmk->seed) 467 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size), 468 crypto_shash_digestsize(lmk->hash_tfm)); 469 470 return 0; 471 } 472 473 static int crypt_iv_lmk_wipe(struct crypt_config *cc) 474 { 475 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 476 477 if (lmk->seed) 478 memset(lmk->seed, 0, LMK_SEED_SIZE); 479 480 return 0; 481 } 482 483 static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv, 484 struct dm_crypt_request *dmreq, 485 u8 *data) 486 { 487 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 488 SHASH_DESC_ON_STACK(desc, lmk->hash_tfm); 489 struct md5_state md5state; 490 __le32 buf[4]; 491 int i, r; 492 493 desc->tfm = lmk->hash_tfm; 494 495 r = crypto_shash_init(desc); 496 if (r) 497 return r; 498 499 if (lmk->seed) { 500 r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE); 501 if (r) 502 return r; 503 } 504 505 /* Sector is always 512B, block size 16, add data of blocks 1-31 */ 506 r = crypto_shash_update(desc, data + 16, 16 * 31); 507 if (r) 508 return r; 509 510 /* Sector is cropped to 56 bits here */ 511 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF); 512 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000); 513 buf[2] = cpu_to_le32(4024); 514 buf[3] = 0; 515 r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf)); 516 if (r) 517 return r; 518 519 /* No MD5 padding here */ 520 r = crypto_shash_export(desc, &md5state); 521 if (r) 522 return r; 523 524 for (i = 0; i < MD5_HASH_WORDS; i++) 525 __cpu_to_le32s(&md5state.hash[i]); 526 memcpy(iv, &md5state.hash, cc->iv_size); 527 528 return 0; 529 } 530 531 static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv, 532 struct dm_crypt_request *dmreq) 533 { 534 struct scatterlist *sg; 535 u8 *src; 536 int r = 0; 537 538 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 539 sg = crypt_get_sg_data(cc, dmreq->sg_in); 540 src = kmap_local_page(sg_page(sg)); 541 r = crypt_iv_lmk_one(cc, iv, dmreq, src + sg->offset); 542 kunmap_local(src); 543 } else 544 memset(iv, 0, cc->iv_size); 545 546 return r; 547 } 548 549 static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv, 550 struct dm_crypt_request *dmreq) 551 { 552 struct scatterlist *sg; 553 u8 *dst; 554 int r; 555 556 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) 557 return 0; 558 559 sg = crypt_get_sg_data(cc, dmreq->sg_out); 560 dst = kmap_local_page(sg_page(sg)); 561 r = crypt_iv_lmk_one(cc, iv, dmreq, dst + sg->offset); 562 563 /* Tweak the first block of plaintext sector */ 564 if (!r) 565 crypto_xor(dst + sg->offset, iv, cc->iv_size); 566 567 kunmap_local(dst); 568 return r; 569 } 570 571 static void crypt_iv_tcw_dtr(struct crypt_config *cc) 572 { 573 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 574 575 kfree_sensitive(tcw->iv_seed); 576 tcw->iv_seed = NULL; 577 kfree_sensitive(tcw->whitening); 578 tcw->whitening = NULL; 579 580 if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm)) 581 crypto_free_shash(tcw->crc32_tfm); 582 tcw->crc32_tfm = NULL; 583 } 584 585 static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti, 586 const char *opts) 587 { 588 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 589 590 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 591 ti->error = "Unsupported sector size for TCW"; 592 return -EINVAL; 593 } 594 595 if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) { 596 ti->error = "Wrong key size for TCW"; 597 return -EINVAL; 598 } 599 600 tcw->crc32_tfm = crypto_alloc_shash("crc32", 0, 601 CRYPTO_ALG_ALLOCATES_MEMORY); 602 if (IS_ERR(tcw->crc32_tfm)) { 603 ti->error = "Error initializing CRC32 in TCW"; 604 return PTR_ERR(tcw->crc32_tfm); 605 } 606 607 tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL); 608 tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL); 609 if (!tcw->iv_seed || !tcw->whitening) { 610 crypt_iv_tcw_dtr(cc); 611 ti->error = "Error allocating seed storage in TCW"; 612 return -ENOMEM; 613 } 614 615 return 0; 616 } 617 618 static int crypt_iv_tcw_init(struct crypt_config *cc) 619 { 620 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 621 int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE; 622 623 memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size); 624 memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size], 625 TCW_WHITENING_SIZE); 626 627 return 0; 628 } 629 630 static int crypt_iv_tcw_wipe(struct crypt_config *cc) 631 { 632 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 633 634 memset(tcw->iv_seed, 0, cc->iv_size); 635 memset(tcw->whitening, 0, TCW_WHITENING_SIZE); 636 637 return 0; 638 } 639 640 static int crypt_iv_tcw_whitening(struct crypt_config *cc, 641 struct dm_crypt_request *dmreq, 642 u8 *data) 643 { 644 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 645 __le64 sector = cpu_to_le64(dmreq->iv_sector); 646 u8 buf[TCW_WHITENING_SIZE]; 647 SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm); 648 int i, r; 649 650 /* xor whitening with sector number */ 651 crypto_xor_cpy(buf, tcw->whitening, (u8 *)§or, 8); 652 crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)§or, 8); 653 654 /* calculate crc32 for every 32bit part and xor it */ 655 desc->tfm = tcw->crc32_tfm; 656 for (i = 0; i < 4; i++) { 657 r = crypto_shash_init(desc); 658 if (r) 659 goto out; 660 r = crypto_shash_update(desc, &buf[i * 4], 4); 661 if (r) 662 goto out; 663 r = crypto_shash_final(desc, &buf[i * 4]); 664 if (r) 665 goto out; 666 } 667 crypto_xor(&buf[0], &buf[12], 4); 668 crypto_xor(&buf[4], &buf[8], 4); 669 670 /* apply whitening (8 bytes) to whole sector */ 671 for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++) 672 crypto_xor(data + i * 8, buf, 8); 673 out: 674 memzero_explicit(buf, sizeof(buf)); 675 return r; 676 } 677 678 static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv, 679 struct dm_crypt_request *dmreq) 680 { 681 struct scatterlist *sg; 682 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 683 __le64 sector = cpu_to_le64(dmreq->iv_sector); 684 u8 *src; 685 int r = 0; 686 687 /* Remove whitening from ciphertext */ 688 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 689 sg = crypt_get_sg_data(cc, dmreq->sg_in); 690 src = kmap_local_page(sg_page(sg)); 691 r = crypt_iv_tcw_whitening(cc, dmreq, src + sg->offset); 692 kunmap_local(src); 693 } 694 695 /* Calculate IV */ 696 crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)§or, 8); 697 if (cc->iv_size > 8) 698 crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)§or, 699 cc->iv_size - 8); 700 701 return r; 702 } 703 704 static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv, 705 struct dm_crypt_request *dmreq) 706 { 707 struct scatterlist *sg; 708 u8 *dst; 709 int r; 710 711 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 712 return 0; 713 714 /* Apply whitening on ciphertext */ 715 sg = crypt_get_sg_data(cc, dmreq->sg_out); 716 dst = kmap_local_page(sg_page(sg)); 717 r = crypt_iv_tcw_whitening(cc, dmreq, dst + sg->offset); 718 kunmap_local(dst); 719 720 return r; 721 } 722 723 static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv, 724 struct dm_crypt_request *dmreq) 725 { 726 /* Used only for writes, there must be an additional space to store IV */ 727 get_random_bytes(iv, cc->iv_size); 728 return 0; 729 } 730 731 static int crypt_iv_eboiv_ctr(struct crypt_config *cc, struct dm_target *ti, 732 const char *opts) 733 { 734 if (crypt_integrity_aead(cc)) { 735 ti->error = "AEAD transforms not supported for EBOIV"; 736 return -EINVAL; 737 } 738 739 if (crypto_skcipher_blocksize(any_tfm(cc)) != cc->iv_size) { 740 ti->error = "Block size of EBOIV cipher does not match IV size of block cipher"; 741 return -EINVAL; 742 } 743 744 return 0; 745 } 746 747 static int crypt_iv_eboiv_gen(struct crypt_config *cc, u8 *iv, 748 struct dm_crypt_request *dmreq) 749 { 750 struct crypto_skcipher *tfm = any_tfm(cc); 751 struct skcipher_request *req; 752 struct scatterlist src, dst; 753 DECLARE_CRYPTO_WAIT(wait); 754 unsigned int reqsize; 755 int err; 756 u8 *buf; 757 758 reqsize = sizeof(*req) + crypto_skcipher_reqsize(tfm); 759 reqsize = ALIGN(reqsize, __alignof__(__le64)); 760 761 req = kmalloc(reqsize + cc->iv_size, GFP_NOIO); 762 if (!req) 763 return -ENOMEM; 764 765 skcipher_request_set_tfm(req, tfm); 766 767 buf = (u8 *)req + reqsize; 768 memset(buf, 0, cc->iv_size); 769 *(__le64 *)buf = cpu_to_le64(dmreq->iv_sector * cc->sector_size); 770 771 sg_init_one(&src, page_address(ZERO_PAGE(0)), cc->iv_size); 772 sg_init_one(&dst, iv, cc->iv_size); 773 skcipher_request_set_crypt(req, &src, &dst, cc->iv_size, buf); 774 skcipher_request_set_callback(req, 0, crypto_req_done, &wait); 775 err = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 776 kfree_sensitive(req); 777 778 return err; 779 } 780 781 static void crypt_iv_elephant_dtr(struct crypt_config *cc) 782 { 783 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 784 785 crypto_free_skcipher(elephant->tfm); 786 elephant->tfm = NULL; 787 } 788 789 static int crypt_iv_elephant_ctr(struct crypt_config *cc, struct dm_target *ti, 790 const char *opts) 791 { 792 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 793 int r; 794 795 elephant->tfm = crypto_alloc_skcipher("ecb(aes)", 0, 796 CRYPTO_ALG_ALLOCATES_MEMORY); 797 if (IS_ERR(elephant->tfm)) { 798 r = PTR_ERR(elephant->tfm); 799 elephant->tfm = NULL; 800 return r; 801 } 802 803 r = crypt_iv_eboiv_ctr(cc, ti, NULL); 804 if (r) 805 crypt_iv_elephant_dtr(cc); 806 return r; 807 } 808 809 static void diffuser_disk_to_cpu(u32 *d, size_t n) 810 { 811 #ifndef __LITTLE_ENDIAN 812 int i; 813 814 for (i = 0; i < n; i++) 815 d[i] = le32_to_cpu((__le32)d[i]); 816 #endif 817 } 818 819 static void diffuser_cpu_to_disk(__le32 *d, size_t n) 820 { 821 #ifndef __LITTLE_ENDIAN 822 int i; 823 824 for (i = 0; i < n; i++) 825 d[i] = cpu_to_le32((u32)d[i]); 826 #endif 827 } 828 829 static void diffuser_a_decrypt(u32 *d, size_t n) 830 { 831 int i, i1, i2, i3; 832 833 for (i = 0; i < 5; i++) { 834 i1 = 0; 835 i2 = n - 2; 836 i3 = n - 5; 837 838 while (i1 < (n - 1)) { 839 d[i1] += d[i2] ^ (d[i3] << 9 | d[i3] >> 23); 840 i1++; i2++; i3++; 841 842 if (i3 >= n) 843 i3 -= n; 844 845 d[i1] += d[i2] ^ d[i3]; 846 i1++; i2++; i3++; 847 848 if (i2 >= n) 849 i2 -= n; 850 851 d[i1] += d[i2] ^ (d[i3] << 13 | d[i3] >> 19); 852 i1++; i2++; i3++; 853 854 d[i1] += d[i2] ^ d[i3]; 855 i1++; i2++; i3++; 856 } 857 } 858 } 859 860 static void diffuser_a_encrypt(u32 *d, size_t n) 861 { 862 int i, i1, i2, i3; 863 864 for (i = 0; i < 5; i++) { 865 i1 = n - 1; 866 i2 = n - 2 - 1; 867 i3 = n - 5 - 1; 868 869 while (i1 > 0) { 870 d[i1] -= d[i2] ^ d[i3]; 871 i1--; i2--; i3--; 872 873 d[i1] -= d[i2] ^ (d[i3] << 13 | d[i3] >> 19); 874 i1--; i2--; i3--; 875 876 if (i2 < 0) 877 i2 += n; 878 879 d[i1] -= d[i2] ^ d[i3]; 880 i1--; i2--; i3--; 881 882 if (i3 < 0) 883 i3 += n; 884 885 d[i1] -= d[i2] ^ (d[i3] << 9 | d[i3] >> 23); 886 i1--; i2--; i3--; 887 } 888 } 889 } 890 891 static void diffuser_b_decrypt(u32 *d, size_t n) 892 { 893 int i, i1, i2, i3; 894 895 for (i = 0; i < 3; i++) { 896 i1 = 0; 897 i2 = 2; 898 i3 = 5; 899 900 while (i1 < (n - 1)) { 901 d[i1] += d[i2] ^ d[i3]; 902 i1++; i2++; i3++; 903 904 d[i1] += d[i2] ^ (d[i3] << 10 | d[i3] >> 22); 905 i1++; i2++; i3++; 906 907 if (i2 >= n) 908 i2 -= n; 909 910 d[i1] += d[i2] ^ d[i3]; 911 i1++; i2++; i3++; 912 913 if (i3 >= n) 914 i3 -= n; 915 916 d[i1] += d[i2] ^ (d[i3] << 25 | d[i3] >> 7); 917 i1++; i2++; i3++; 918 } 919 } 920 } 921 922 static void diffuser_b_encrypt(u32 *d, size_t n) 923 { 924 int i, i1, i2, i3; 925 926 for (i = 0; i < 3; i++) { 927 i1 = n - 1; 928 i2 = 2 - 1; 929 i3 = 5 - 1; 930 931 while (i1 > 0) { 932 d[i1] -= d[i2] ^ (d[i3] << 25 | d[i3] >> 7); 933 i1--; i2--; i3--; 934 935 if (i3 < 0) 936 i3 += n; 937 938 d[i1] -= d[i2] ^ d[i3]; 939 i1--; i2--; i3--; 940 941 if (i2 < 0) 942 i2 += n; 943 944 d[i1] -= d[i2] ^ (d[i3] << 10 | d[i3] >> 22); 945 i1--; i2--; i3--; 946 947 d[i1] -= d[i2] ^ d[i3]; 948 i1--; i2--; i3--; 949 } 950 } 951 } 952 953 static int crypt_iv_elephant(struct crypt_config *cc, struct dm_crypt_request *dmreq) 954 { 955 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 956 u8 *es, *ks, *data, *data2, *data_offset; 957 struct skcipher_request *req; 958 struct scatterlist *sg, *sg2, src, dst; 959 DECLARE_CRYPTO_WAIT(wait); 960 int i, r; 961 962 req = skcipher_request_alloc(elephant->tfm, GFP_NOIO); 963 es = kzalloc(16, GFP_NOIO); /* Key for AES */ 964 ks = kzalloc(32, GFP_NOIO); /* Elephant sector key */ 965 966 if (!req || !es || !ks) { 967 r = -ENOMEM; 968 goto out; 969 } 970 971 *(__le64 *)es = cpu_to_le64(dmreq->iv_sector * cc->sector_size); 972 973 /* E(Ks, e(s)) */ 974 sg_init_one(&src, es, 16); 975 sg_init_one(&dst, ks, 16); 976 skcipher_request_set_crypt(req, &src, &dst, 16, NULL); 977 skcipher_request_set_callback(req, 0, crypto_req_done, &wait); 978 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 979 if (r) 980 goto out; 981 982 /* E(Ks, e'(s)) */ 983 es[15] = 0x80; 984 sg_init_one(&dst, &ks[16], 16); 985 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 986 if (r) 987 goto out; 988 989 sg = crypt_get_sg_data(cc, dmreq->sg_out); 990 data = kmap_local_page(sg_page(sg)); 991 data_offset = data + sg->offset; 992 993 /* Cannot modify original bio, copy to sg_out and apply Elephant to it */ 994 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 995 sg2 = crypt_get_sg_data(cc, dmreq->sg_in); 996 data2 = kmap_local_page(sg_page(sg2)); 997 memcpy(data_offset, data2 + sg2->offset, cc->sector_size); 998 kunmap_local(data2); 999 } 1000 1001 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 1002 diffuser_disk_to_cpu((u32 *)data_offset, cc->sector_size / sizeof(u32)); 1003 diffuser_b_decrypt((u32 *)data_offset, cc->sector_size / sizeof(u32)); 1004 diffuser_a_decrypt((u32 *)data_offset, cc->sector_size / sizeof(u32)); 1005 diffuser_cpu_to_disk((__le32 *)data_offset, cc->sector_size / sizeof(u32)); 1006 } 1007 1008 for (i = 0; i < (cc->sector_size / 32); i++) 1009 crypto_xor(data_offset + i * 32, ks, 32); 1010 1011 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 1012 diffuser_disk_to_cpu((u32 *)data_offset, cc->sector_size / sizeof(u32)); 1013 diffuser_a_encrypt((u32 *)data_offset, cc->sector_size / sizeof(u32)); 1014 diffuser_b_encrypt((u32 *)data_offset, cc->sector_size / sizeof(u32)); 1015 diffuser_cpu_to_disk((__le32 *)data_offset, cc->sector_size / sizeof(u32)); 1016 } 1017 1018 kunmap_local(data); 1019 out: 1020 kfree_sensitive(ks); 1021 kfree_sensitive(es); 1022 skcipher_request_free(req); 1023 return r; 1024 } 1025 1026 static int crypt_iv_elephant_gen(struct crypt_config *cc, u8 *iv, 1027 struct dm_crypt_request *dmreq) 1028 { 1029 int r; 1030 1031 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 1032 r = crypt_iv_elephant(cc, dmreq); 1033 if (r) 1034 return r; 1035 } 1036 1037 return crypt_iv_eboiv_gen(cc, iv, dmreq); 1038 } 1039 1040 static int crypt_iv_elephant_post(struct crypt_config *cc, u8 *iv, 1041 struct dm_crypt_request *dmreq) 1042 { 1043 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 1044 return crypt_iv_elephant(cc, dmreq); 1045 1046 return 0; 1047 } 1048 1049 static int crypt_iv_elephant_init(struct crypt_config *cc) 1050 { 1051 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 1052 int key_offset = cc->key_size - cc->key_extra_size; 1053 1054 return crypto_skcipher_setkey(elephant->tfm, &cc->key[key_offset], cc->key_extra_size); 1055 } 1056 1057 static int crypt_iv_elephant_wipe(struct crypt_config *cc) 1058 { 1059 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 1060 u8 key[ELEPHANT_MAX_KEY_SIZE]; 1061 1062 memset(key, 0, cc->key_extra_size); 1063 return crypto_skcipher_setkey(elephant->tfm, key, cc->key_extra_size); 1064 } 1065 1066 static const struct crypt_iv_operations crypt_iv_plain_ops = { 1067 .generator = crypt_iv_plain_gen 1068 }; 1069 1070 static const struct crypt_iv_operations crypt_iv_plain64_ops = { 1071 .generator = crypt_iv_plain64_gen 1072 }; 1073 1074 static const struct crypt_iv_operations crypt_iv_plain64be_ops = { 1075 .generator = crypt_iv_plain64be_gen 1076 }; 1077 1078 static const struct crypt_iv_operations crypt_iv_essiv_ops = { 1079 .generator = crypt_iv_essiv_gen 1080 }; 1081 1082 static const struct crypt_iv_operations crypt_iv_benbi_ops = { 1083 .ctr = crypt_iv_benbi_ctr, 1084 .dtr = crypt_iv_benbi_dtr, 1085 .generator = crypt_iv_benbi_gen 1086 }; 1087 1088 static const struct crypt_iv_operations crypt_iv_null_ops = { 1089 .generator = crypt_iv_null_gen 1090 }; 1091 1092 static const struct crypt_iv_operations crypt_iv_lmk_ops = { 1093 .ctr = crypt_iv_lmk_ctr, 1094 .dtr = crypt_iv_lmk_dtr, 1095 .init = crypt_iv_lmk_init, 1096 .wipe = crypt_iv_lmk_wipe, 1097 .generator = crypt_iv_lmk_gen, 1098 .post = crypt_iv_lmk_post 1099 }; 1100 1101 static const struct crypt_iv_operations crypt_iv_tcw_ops = { 1102 .ctr = crypt_iv_tcw_ctr, 1103 .dtr = crypt_iv_tcw_dtr, 1104 .init = crypt_iv_tcw_init, 1105 .wipe = crypt_iv_tcw_wipe, 1106 .generator = crypt_iv_tcw_gen, 1107 .post = crypt_iv_tcw_post 1108 }; 1109 1110 static const struct crypt_iv_operations crypt_iv_random_ops = { 1111 .generator = crypt_iv_random_gen 1112 }; 1113 1114 static const struct crypt_iv_operations crypt_iv_eboiv_ops = { 1115 .ctr = crypt_iv_eboiv_ctr, 1116 .generator = crypt_iv_eboiv_gen 1117 }; 1118 1119 static const struct crypt_iv_operations crypt_iv_elephant_ops = { 1120 .ctr = crypt_iv_elephant_ctr, 1121 .dtr = crypt_iv_elephant_dtr, 1122 .init = crypt_iv_elephant_init, 1123 .wipe = crypt_iv_elephant_wipe, 1124 .generator = crypt_iv_elephant_gen, 1125 .post = crypt_iv_elephant_post 1126 }; 1127 1128 /* 1129 * Integrity extensions 1130 */ 1131 static bool crypt_integrity_aead(struct crypt_config *cc) 1132 { 1133 return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 1134 } 1135 1136 static bool crypt_integrity_hmac(struct crypt_config *cc) 1137 { 1138 return crypt_integrity_aead(cc) && cc->key_mac_size; 1139 } 1140 1141 /* Get sg containing data */ 1142 static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 1143 struct scatterlist *sg) 1144 { 1145 if (unlikely(crypt_integrity_aead(cc))) 1146 return &sg[2]; 1147 1148 return sg; 1149 } 1150 1151 static int dm_crypt_integrity_io_alloc(struct dm_crypt_io *io, struct bio *bio) 1152 { 1153 struct bio_integrity_payload *bip; 1154 unsigned int tag_len; 1155 int ret; 1156 1157 if (!bio_sectors(bio) || !io->cc->on_disk_tag_size) 1158 return 0; 1159 1160 bip = bio_integrity_alloc(bio, GFP_NOIO, 1); 1161 if (IS_ERR(bip)) 1162 return PTR_ERR(bip); 1163 1164 tag_len = io->cc->on_disk_tag_size * (bio_sectors(bio) >> io->cc->sector_shift); 1165 1166 bip->bip_iter.bi_sector = io->cc->start + io->sector; 1167 1168 ret = bio_integrity_add_page(bio, virt_to_page(io->integrity_metadata), 1169 tag_len, offset_in_page(io->integrity_metadata)); 1170 if (unlikely(ret != tag_len)) 1171 return -ENOMEM; 1172 1173 return 0; 1174 } 1175 1176 static int crypt_integrity_ctr(struct crypt_config *cc, struct dm_target *ti) 1177 { 1178 #ifdef CONFIG_BLK_DEV_INTEGRITY 1179 struct blk_integrity *bi = blk_get_integrity(cc->dev->bdev->bd_disk); 1180 struct mapped_device *md = dm_table_get_md(ti->table); 1181 1182 /* From now we require underlying device with our integrity profile */ 1183 if (!bi || strcasecmp(bi->profile->name, "DM-DIF-EXT-TAG")) { 1184 ti->error = "Integrity profile not supported."; 1185 return -EINVAL; 1186 } 1187 1188 if (bi->tag_size != cc->on_disk_tag_size || 1189 bi->tuple_size != cc->on_disk_tag_size) { 1190 ti->error = "Integrity profile tag size mismatch."; 1191 return -EINVAL; 1192 } 1193 if (1 << bi->interval_exp != cc->sector_size) { 1194 ti->error = "Integrity profile sector size mismatch."; 1195 return -EINVAL; 1196 } 1197 1198 if (crypt_integrity_aead(cc)) { 1199 cc->integrity_tag_size = cc->on_disk_tag_size - cc->integrity_iv_size; 1200 DMDEBUG("%s: Integrity AEAD, tag size %u, IV size %u.", dm_device_name(md), 1201 cc->integrity_tag_size, cc->integrity_iv_size); 1202 1203 if (crypto_aead_setauthsize(any_tfm_aead(cc), cc->integrity_tag_size)) { 1204 ti->error = "Integrity AEAD auth tag size is not supported."; 1205 return -EINVAL; 1206 } 1207 } else if (cc->integrity_iv_size) 1208 DMDEBUG("%s: Additional per-sector space %u bytes for IV.", dm_device_name(md), 1209 cc->integrity_iv_size); 1210 1211 if ((cc->integrity_tag_size + cc->integrity_iv_size) != bi->tag_size) { 1212 ti->error = "Not enough space for integrity tag in the profile."; 1213 return -EINVAL; 1214 } 1215 1216 return 0; 1217 #else 1218 ti->error = "Integrity profile not supported."; 1219 return -EINVAL; 1220 #endif 1221 } 1222 1223 static void crypt_convert_init(struct crypt_config *cc, 1224 struct convert_context *ctx, 1225 struct bio *bio_out, struct bio *bio_in, 1226 sector_t sector) 1227 { 1228 ctx->bio_in = bio_in; 1229 ctx->bio_out = bio_out; 1230 if (bio_in) 1231 ctx->iter_in = bio_in->bi_iter; 1232 if (bio_out) 1233 ctx->iter_out = bio_out->bi_iter; 1234 ctx->cc_sector = sector + cc->iv_offset; 1235 init_completion(&ctx->restart); 1236 } 1237 1238 static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc, 1239 void *req) 1240 { 1241 return (struct dm_crypt_request *)((char *)req + cc->dmreq_start); 1242 } 1243 1244 static void *req_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq) 1245 { 1246 return (void *)((char *)dmreq - cc->dmreq_start); 1247 } 1248 1249 static u8 *iv_of_dmreq(struct crypt_config *cc, 1250 struct dm_crypt_request *dmreq) 1251 { 1252 if (crypt_integrity_aead(cc)) 1253 return (u8 *)ALIGN((unsigned long)(dmreq + 1), 1254 crypto_aead_alignmask(any_tfm_aead(cc)) + 1); 1255 else 1256 return (u8 *)ALIGN((unsigned long)(dmreq + 1), 1257 crypto_skcipher_alignmask(any_tfm(cc)) + 1); 1258 } 1259 1260 static u8 *org_iv_of_dmreq(struct crypt_config *cc, 1261 struct dm_crypt_request *dmreq) 1262 { 1263 return iv_of_dmreq(cc, dmreq) + cc->iv_size; 1264 } 1265 1266 static __le64 *org_sector_of_dmreq(struct crypt_config *cc, 1267 struct dm_crypt_request *dmreq) 1268 { 1269 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + cc->iv_size; 1270 1271 return (__le64 *) ptr; 1272 } 1273 1274 static unsigned int *org_tag_of_dmreq(struct crypt_config *cc, 1275 struct dm_crypt_request *dmreq) 1276 { 1277 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + 1278 cc->iv_size + sizeof(uint64_t); 1279 1280 return (unsigned int *)ptr; 1281 } 1282 1283 static void *tag_from_dmreq(struct crypt_config *cc, 1284 struct dm_crypt_request *dmreq) 1285 { 1286 struct convert_context *ctx = dmreq->ctx; 1287 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 1288 1289 return &io->integrity_metadata[*org_tag_of_dmreq(cc, dmreq) * 1290 cc->on_disk_tag_size]; 1291 } 1292 1293 static void *iv_tag_from_dmreq(struct crypt_config *cc, 1294 struct dm_crypt_request *dmreq) 1295 { 1296 return tag_from_dmreq(cc, dmreq) + cc->integrity_tag_size; 1297 } 1298 1299 static int crypt_convert_block_aead(struct crypt_config *cc, 1300 struct convert_context *ctx, 1301 struct aead_request *req, 1302 unsigned int tag_offset) 1303 { 1304 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1305 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1306 struct dm_crypt_request *dmreq; 1307 u8 *iv, *org_iv, *tag_iv, *tag; 1308 __le64 *sector; 1309 int r = 0; 1310 1311 BUG_ON(cc->integrity_iv_size && cc->integrity_iv_size != cc->iv_size); 1312 1313 /* Reject unexpected unaligned bio. */ 1314 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1315 return -EIO; 1316 1317 dmreq = dmreq_of_req(cc, req); 1318 dmreq->iv_sector = ctx->cc_sector; 1319 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1320 dmreq->iv_sector >>= cc->sector_shift; 1321 dmreq->ctx = ctx; 1322 1323 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1324 1325 sector = org_sector_of_dmreq(cc, dmreq); 1326 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1327 1328 iv = iv_of_dmreq(cc, dmreq); 1329 org_iv = org_iv_of_dmreq(cc, dmreq); 1330 tag = tag_from_dmreq(cc, dmreq); 1331 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1332 1333 /* AEAD request: 1334 * |----- AAD -------|------ DATA -------|-- AUTH TAG --| 1335 * | (authenticated) | (auth+encryption) | | 1336 * | sector_LE | IV | sector in/out | tag in/out | 1337 */ 1338 sg_init_table(dmreq->sg_in, 4); 1339 sg_set_buf(&dmreq->sg_in[0], sector, sizeof(uint64_t)); 1340 sg_set_buf(&dmreq->sg_in[1], org_iv, cc->iv_size); 1341 sg_set_page(&dmreq->sg_in[2], bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1342 sg_set_buf(&dmreq->sg_in[3], tag, cc->integrity_tag_size); 1343 1344 sg_init_table(dmreq->sg_out, 4); 1345 sg_set_buf(&dmreq->sg_out[0], sector, sizeof(uint64_t)); 1346 sg_set_buf(&dmreq->sg_out[1], org_iv, cc->iv_size); 1347 sg_set_page(&dmreq->sg_out[2], bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1348 sg_set_buf(&dmreq->sg_out[3], tag, cc->integrity_tag_size); 1349 1350 if (cc->iv_gen_ops) { 1351 /* For READs use IV stored in integrity metadata */ 1352 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1353 memcpy(org_iv, tag_iv, cc->iv_size); 1354 } else { 1355 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1356 if (r < 0) 1357 return r; 1358 /* Store generated IV in integrity metadata */ 1359 if (cc->integrity_iv_size) 1360 memcpy(tag_iv, org_iv, cc->iv_size); 1361 } 1362 /* Working copy of IV, to be modified in crypto API */ 1363 memcpy(iv, org_iv, cc->iv_size); 1364 } 1365 1366 aead_request_set_ad(req, sizeof(uint64_t) + cc->iv_size); 1367 if (bio_data_dir(ctx->bio_in) == WRITE) { 1368 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out, 1369 cc->sector_size, iv); 1370 r = crypto_aead_encrypt(req); 1371 if (cc->integrity_tag_size + cc->integrity_iv_size != cc->on_disk_tag_size) 1372 memset(tag + cc->integrity_tag_size + cc->integrity_iv_size, 0, 1373 cc->on_disk_tag_size - (cc->integrity_tag_size + cc->integrity_iv_size)); 1374 } else { 1375 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out, 1376 cc->sector_size + cc->integrity_tag_size, iv); 1377 r = crypto_aead_decrypt(req); 1378 } 1379 1380 if (r == -EBADMSG) { 1381 sector_t s = le64_to_cpu(*sector); 1382 1383 ctx->aead_failed = true; 1384 if (ctx->aead_recheck) { 1385 DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu", 1386 ctx->bio_in->bi_bdev, s); 1387 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead", 1388 ctx->bio_in, s, 0); 1389 } 1390 } 1391 1392 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1393 r = cc->iv_gen_ops->post(cc, org_iv, dmreq); 1394 1395 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1396 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1397 1398 return r; 1399 } 1400 1401 static int crypt_convert_block_skcipher(struct crypt_config *cc, 1402 struct convert_context *ctx, 1403 struct skcipher_request *req, 1404 unsigned int tag_offset) 1405 { 1406 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1407 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1408 struct scatterlist *sg_in, *sg_out; 1409 struct dm_crypt_request *dmreq; 1410 u8 *iv, *org_iv, *tag_iv; 1411 __le64 *sector; 1412 int r = 0; 1413 1414 /* Reject unexpected unaligned bio. */ 1415 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1416 return -EIO; 1417 1418 dmreq = dmreq_of_req(cc, req); 1419 dmreq->iv_sector = ctx->cc_sector; 1420 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1421 dmreq->iv_sector >>= cc->sector_shift; 1422 dmreq->ctx = ctx; 1423 1424 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1425 1426 iv = iv_of_dmreq(cc, dmreq); 1427 org_iv = org_iv_of_dmreq(cc, dmreq); 1428 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1429 1430 sector = org_sector_of_dmreq(cc, dmreq); 1431 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1432 1433 /* For skcipher we use only the first sg item */ 1434 sg_in = &dmreq->sg_in[0]; 1435 sg_out = &dmreq->sg_out[0]; 1436 1437 sg_init_table(sg_in, 1); 1438 sg_set_page(sg_in, bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1439 1440 sg_init_table(sg_out, 1); 1441 sg_set_page(sg_out, bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1442 1443 if (cc->iv_gen_ops) { 1444 /* For READs use IV stored in integrity metadata */ 1445 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1446 memcpy(org_iv, tag_iv, cc->integrity_iv_size); 1447 } else { 1448 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1449 if (r < 0) 1450 return r; 1451 /* Data can be already preprocessed in generator */ 1452 if (test_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags)) 1453 sg_in = sg_out; 1454 /* Store generated IV in integrity metadata */ 1455 if (cc->integrity_iv_size) 1456 memcpy(tag_iv, org_iv, cc->integrity_iv_size); 1457 } 1458 /* Working copy of IV, to be modified in crypto API */ 1459 memcpy(iv, org_iv, cc->iv_size); 1460 } 1461 1462 skcipher_request_set_crypt(req, sg_in, sg_out, cc->sector_size, iv); 1463 1464 if (bio_data_dir(ctx->bio_in) == WRITE) 1465 r = crypto_skcipher_encrypt(req); 1466 else 1467 r = crypto_skcipher_decrypt(req); 1468 1469 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1470 r = cc->iv_gen_ops->post(cc, org_iv, dmreq); 1471 1472 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1473 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1474 1475 return r; 1476 } 1477 1478 static void kcryptd_async_done(void *async_req, int error); 1479 1480 static int crypt_alloc_req_skcipher(struct crypt_config *cc, 1481 struct convert_context *ctx) 1482 { 1483 unsigned int key_index = ctx->cc_sector & (cc->tfms_count - 1); 1484 1485 if (!ctx->r.req) { 1486 ctx->r.req = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1487 if (!ctx->r.req) 1488 return -ENOMEM; 1489 } 1490 1491 skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]); 1492 1493 /* 1494 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1495 * requests if driver request queue is full. 1496 */ 1497 skcipher_request_set_callback(ctx->r.req, 1498 CRYPTO_TFM_REQ_MAY_BACKLOG, 1499 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req)); 1500 1501 return 0; 1502 } 1503 1504 static int crypt_alloc_req_aead(struct crypt_config *cc, 1505 struct convert_context *ctx) 1506 { 1507 if (!ctx->r.req_aead) { 1508 ctx->r.req_aead = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1509 if (!ctx->r.req_aead) 1510 return -ENOMEM; 1511 } 1512 1513 aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]); 1514 1515 /* 1516 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1517 * requests if driver request queue is full. 1518 */ 1519 aead_request_set_callback(ctx->r.req_aead, 1520 CRYPTO_TFM_REQ_MAY_BACKLOG, 1521 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead)); 1522 1523 return 0; 1524 } 1525 1526 static int crypt_alloc_req(struct crypt_config *cc, 1527 struct convert_context *ctx) 1528 { 1529 if (crypt_integrity_aead(cc)) 1530 return crypt_alloc_req_aead(cc, ctx); 1531 else 1532 return crypt_alloc_req_skcipher(cc, ctx); 1533 } 1534 1535 static void crypt_free_req_skcipher(struct crypt_config *cc, 1536 struct skcipher_request *req, struct bio *base_bio) 1537 { 1538 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1539 1540 if ((struct skcipher_request *)(io + 1) != req) 1541 mempool_free(req, &cc->req_pool); 1542 } 1543 1544 static void crypt_free_req_aead(struct crypt_config *cc, 1545 struct aead_request *req, struct bio *base_bio) 1546 { 1547 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1548 1549 if ((struct aead_request *)(io + 1) != req) 1550 mempool_free(req, &cc->req_pool); 1551 } 1552 1553 static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio) 1554 { 1555 if (crypt_integrity_aead(cc)) 1556 crypt_free_req_aead(cc, req, base_bio); 1557 else 1558 crypt_free_req_skcipher(cc, req, base_bio); 1559 } 1560 1561 /* 1562 * Encrypt / decrypt data from one bio to another one (can be the same one) 1563 */ 1564 static blk_status_t crypt_convert(struct crypt_config *cc, 1565 struct convert_context *ctx, bool atomic, bool reset_pending) 1566 { 1567 unsigned int tag_offset = 0; 1568 unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT; 1569 int r; 1570 1571 /* 1572 * if reset_pending is set we are dealing with the bio for the first time, 1573 * else we're continuing to work on the previous bio, so don't mess with 1574 * the cc_pending counter 1575 */ 1576 if (reset_pending) 1577 atomic_set(&ctx->cc_pending, 1); 1578 1579 while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) { 1580 1581 r = crypt_alloc_req(cc, ctx); 1582 if (r) { 1583 complete(&ctx->restart); 1584 return BLK_STS_DEV_RESOURCE; 1585 } 1586 1587 atomic_inc(&ctx->cc_pending); 1588 1589 if (crypt_integrity_aead(cc)) 1590 r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, tag_offset); 1591 else 1592 r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, tag_offset); 1593 1594 switch (r) { 1595 /* 1596 * The request was queued by a crypto driver 1597 * but the driver request queue is full, let's wait. 1598 */ 1599 case -EBUSY: 1600 if (in_interrupt()) { 1601 if (try_wait_for_completion(&ctx->restart)) { 1602 /* 1603 * we don't have to block to wait for completion, 1604 * so proceed 1605 */ 1606 } else { 1607 /* 1608 * we can't wait for completion without blocking 1609 * exit and continue processing in a workqueue 1610 */ 1611 ctx->r.req = NULL; 1612 ctx->cc_sector += sector_step; 1613 tag_offset++; 1614 return BLK_STS_DEV_RESOURCE; 1615 } 1616 } else { 1617 wait_for_completion(&ctx->restart); 1618 } 1619 reinit_completion(&ctx->restart); 1620 fallthrough; 1621 /* 1622 * The request is queued and processed asynchronously, 1623 * completion function kcryptd_async_done() will be called. 1624 */ 1625 case -EINPROGRESS: 1626 ctx->r.req = NULL; 1627 ctx->cc_sector += sector_step; 1628 tag_offset++; 1629 continue; 1630 /* 1631 * The request was already processed (synchronously). 1632 */ 1633 case 0: 1634 atomic_dec(&ctx->cc_pending); 1635 ctx->cc_sector += sector_step; 1636 tag_offset++; 1637 if (!atomic) 1638 cond_resched(); 1639 continue; 1640 /* 1641 * There was a data integrity error. 1642 */ 1643 case -EBADMSG: 1644 atomic_dec(&ctx->cc_pending); 1645 return BLK_STS_PROTECTION; 1646 /* 1647 * There was an error while processing the request. 1648 */ 1649 default: 1650 atomic_dec(&ctx->cc_pending); 1651 return BLK_STS_IOERR; 1652 } 1653 } 1654 1655 return 0; 1656 } 1657 1658 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone); 1659 1660 /* 1661 * Generate a new unfragmented bio with the given size 1662 * This should never violate the device limitations (but only because 1663 * max_segment_size is being constrained to PAGE_SIZE). 1664 * 1665 * This function may be called concurrently. If we allocate from the mempool 1666 * concurrently, there is a possibility of deadlock. For example, if we have 1667 * mempool of 256 pages, two processes, each wanting 256, pages allocate from 1668 * the mempool concurrently, it may deadlock in a situation where both processes 1669 * have allocated 128 pages and the mempool is exhausted. 1670 * 1671 * In order to avoid this scenario we allocate the pages under a mutex. 1672 * 1673 * In order to not degrade performance with excessive locking, we try 1674 * non-blocking allocations without a mutex first but on failure we fallback 1675 * to blocking allocations with a mutex. 1676 * 1677 * In order to reduce allocation overhead, we try to allocate compound pages in 1678 * the first pass. If they are not available, we fall back to the mempool. 1679 */ 1680 static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned int size) 1681 { 1682 struct crypt_config *cc = io->cc; 1683 struct bio *clone; 1684 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; 1685 gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM; 1686 unsigned int remaining_size; 1687 unsigned int order = MAX_ORDER; 1688 1689 retry: 1690 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1691 mutex_lock(&cc->bio_alloc_lock); 1692 1693 clone = bio_alloc_bioset(cc->dev->bdev, nr_iovecs, io->base_bio->bi_opf, 1694 GFP_NOIO, &cc->bs); 1695 clone->bi_private = io; 1696 clone->bi_end_io = crypt_endio; 1697 1698 remaining_size = size; 1699 1700 while (remaining_size) { 1701 struct page *pages; 1702 unsigned size_to_add; 1703 unsigned remaining_order = __fls((remaining_size + PAGE_SIZE - 1) >> PAGE_SHIFT); 1704 order = min(order, remaining_order); 1705 1706 while (order > 0) { 1707 if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) + 1708 (1 << order) > dm_crypt_pages_per_client)) 1709 goto decrease_order; 1710 pages = alloc_pages(gfp_mask 1711 | __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN | __GFP_COMP, 1712 order); 1713 if (likely(pages != NULL)) { 1714 percpu_counter_add(&cc->n_allocated_pages, 1 << order); 1715 goto have_pages; 1716 } 1717 decrease_order: 1718 order--; 1719 } 1720 1721 pages = mempool_alloc(&cc->page_pool, gfp_mask); 1722 if (!pages) { 1723 crypt_free_buffer_pages(cc, clone); 1724 bio_put(clone); 1725 gfp_mask |= __GFP_DIRECT_RECLAIM; 1726 order = 0; 1727 goto retry; 1728 } 1729 1730 have_pages: 1731 size_to_add = min((unsigned)PAGE_SIZE << order, remaining_size); 1732 __bio_add_page(clone, pages, size_to_add, 0); 1733 remaining_size -= size_to_add; 1734 } 1735 1736 /* Allocate space for integrity tags */ 1737 if (dm_crypt_integrity_io_alloc(io, clone)) { 1738 crypt_free_buffer_pages(cc, clone); 1739 bio_put(clone); 1740 clone = NULL; 1741 } 1742 1743 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1744 mutex_unlock(&cc->bio_alloc_lock); 1745 1746 return clone; 1747 } 1748 1749 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) 1750 { 1751 struct folio_iter fi; 1752 1753 if (clone->bi_vcnt > 0) { /* bio_for_each_folio_all crashes with an empty bio */ 1754 bio_for_each_folio_all(fi, clone) { 1755 if (folio_test_large(fi.folio)) { 1756 percpu_counter_sub(&cc->n_allocated_pages, 1757 1 << folio_order(fi.folio)); 1758 folio_put(fi.folio); 1759 } else { 1760 mempool_free(&fi.folio->page, &cc->page_pool); 1761 } 1762 } 1763 } 1764 } 1765 1766 static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc, 1767 struct bio *bio, sector_t sector) 1768 { 1769 io->cc = cc; 1770 io->base_bio = bio; 1771 io->sector = sector; 1772 io->error = 0; 1773 io->ctx.aead_recheck = false; 1774 io->ctx.aead_failed = false; 1775 io->ctx.r.req = NULL; 1776 io->integrity_metadata = NULL; 1777 io->integrity_metadata_from_pool = false; 1778 atomic_set(&io->io_pending, 0); 1779 } 1780 1781 static void crypt_inc_pending(struct dm_crypt_io *io) 1782 { 1783 atomic_inc(&io->io_pending); 1784 } 1785 1786 static void kcryptd_queue_read(struct dm_crypt_io *io); 1787 1788 /* 1789 * One of the bios was finished. Check for completion of 1790 * the whole request and correctly clean up the buffer. 1791 */ 1792 static void crypt_dec_pending(struct dm_crypt_io *io) 1793 { 1794 struct crypt_config *cc = io->cc; 1795 struct bio *base_bio = io->base_bio; 1796 blk_status_t error = io->error; 1797 1798 if (!atomic_dec_and_test(&io->io_pending)) 1799 return; 1800 1801 if (likely(!io->ctx.aead_recheck) && unlikely(io->ctx.aead_failed) && 1802 cc->on_disk_tag_size && bio_data_dir(base_bio) == READ) { 1803 io->ctx.aead_recheck = true; 1804 io->ctx.aead_failed = false; 1805 io->error = 0; 1806 kcryptd_queue_read(io); 1807 return; 1808 } 1809 1810 if (io->ctx.r.req) 1811 crypt_free_req(cc, io->ctx.r.req, base_bio); 1812 1813 if (unlikely(io->integrity_metadata_from_pool)) 1814 mempool_free(io->integrity_metadata, &io->cc->tag_pool); 1815 else 1816 kfree(io->integrity_metadata); 1817 1818 base_bio->bi_status = error; 1819 1820 bio_endio(base_bio); 1821 } 1822 1823 /* 1824 * kcryptd/kcryptd_io: 1825 * 1826 * Needed because it would be very unwise to do decryption in an 1827 * interrupt context. 1828 * 1829 * kcryptd performs the actual encryption or decryption. 1830 * 1831 * kcryptd_io performs the IO submission. 1832 * 1833 * They must be separated as otherwise the final stages could be 1834 * starved by new requests which can block in the first stages due 1835 * to memory allocation. 1836 * 1837 * The work is done per CPU global for all dm-crypt instances. 1838 * They should not depend on each other and do not block. 1839 */ 1840 static void crypt_endio(struct bio *clone) 1841 { 1842 struct dm_crypt_io *io = clone->bi_private; 1843 struct crypt_config *cc = io->cc; 1844 unsigned int rw = bio_data_dir(clone); 1845 blk_status_t error = clone->bi_status; 1846 1847 if (io->ctx.aead_recheck && !error) { 1848 kcryptd_queue_crypt(io); 1849 return; 1850 } 1851 1852 /* 1853 * free the processed pages 1854 */ 1855 if (rw == WRITE || io->ctx.aead_recheck) 1856 crypt_free_buffer_pages(cc, clone); 1857 1858 bio_put(clone); 1859 1860 if (rw == READ && !error) { 1861 kcryptd_queue_crypt(io); 1862 return; 1863 } 1864 1865 if (unlikely(error)) 1866 io->error = error; 1867 1868 crypt_dec_pending(io); 1869 } 1870 1871 #define CRYPT_MAP_READ_GFP GFP_NOWAIT 1872 1873 static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp) 1874 { 1875 struct crypt_config *cc = io->cc; 1876 struct bio *clone; 1877 1878 if (io->ctx.aead_recheck) { 1879 if (!(gfp & __GFP_DIRECT_RECLAIM)) 1880 return 1; 1881 crypt_inc_pending(io); 1882 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size); 1883 if (unlikely(!clone)) { 1884 crypt_dec_pending(io); 1885 return 1; 1886 } 1887 clone->bi_iter.bi_sector = cc->start + io->sector; 1888 crypt_convert_init(cc, &io->ctx, clone, clone, io->sector); 1889 io->saved_bi_iter = clone->bi_iter; 1890 dm_submit_bio_remap(io->base_bio, clone); 1891 return 0; 1892 } 1893 1894 /* 1895 * We need the original biovec array in order to decrypt the whole bio 1896 * data *afterwards* -- thanks to immutable biovecs we don't need to 1897 * worry about the block layer modifying the biovec array; so leverage 1898 * bio_alloc_clone(). 1899 */ 1900 clone = bio_alloc_clone(cc->dev->bdev, io->base_bio, gfp, &cc->bs); 1901 if (!clone) 1902 return 1; 1903 clone->bi_private = io; 1904 clone->bi_end_io = crypt_endio; 1905 1906 crypt_inc_pending(io); 1907 1908 clone->bi_iter.bi_sector = cc->start + io->sector; 1909 1910 if (dm_crypt_integrity_io_alloc(io, clone)) { 1911 crypt_dec_pending(io); 1912 bio_put(clone); 1913 return 1; 1914 } 1915 1916 dm_submit_bio_remap(io->base_bio, clone); 1917 return 0; 1918 } 1919 1920 static void kcryptd_io_read_work(struct work_struct *work) 1921 { 1922 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 1923 1924 crypt_inc_pending(io); 1925 if (kcryptd_io_read(io, GFP_NOIO)) 1926 io->error = BLK_STS_RESOURCE; 1927 crypt_dec_pending(io); 1928 } 1929 1930 static void kcryptd_queue_read(struct dm_crypt_io *io) 1931 { 1932 struct crypt_config *cc = io->cc; 1933 1934 INIT_WORK(&io->work, kcryptd_io_read_work); 1935 queue_work(cc->io_queue, &io->work); 1936 } 1937 1938 static void kcryptd_io_write(struct dm_crypt_io *io) 1939 { 1940 struct bio *clone = io->ctx.bio_out; 1941 1942 dm_submit_bio_remap(io->base_bio, clone); 1943 } 1944 1945 #define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node) 1946 1947 static int dmcrypt_write(void *data) 1948 { 1949 struct crypt_config *cc = data; 1950 struct dm_crypt_io *io; 1951 1952 while (1) { 1953 struct rb_root write_tree; 1954 struct blk_plug plug; 1955 1956 spin_lock_irq(&cc->write_thread_lock); 1957 continue_locked: 1958 1959 if (!RB_EMPTY_ROOT(&cc->write_tree)) 1960 goto pop_from_list; 1961 1962 set_current_state(TASK_INTERRUPTIBLE); 1963 1964 spin_unlock_irq(&cc->write_thread_lock); 1965 1966 if (unlikely(kthread_should_stop())) { 1967 set_current_state(TASK_RUNNING); 1968 break; 1969 } 1970 1971 schedule(); 1972 1973 set_current_state(TASK_RUNNING); 1974 spin_lock_irq(&cc->write_thread_lock); 1975 goto continue_locked; 1976 1977 pop_from_list: 1978 write_tree = cc->write_tree; 1979 cc->write_tree = RB_ROOT; 1980 spin_unlock_irq(&cc->write_thread_lock); 1981 1982 BUG_ON(rb_parent(write_tree.rb_node)); 1983 1984 /* 1985 * Note: we cannot walk the tree here with rb_next because 1986 * the structures may be freed when kcryptd_io_write is called. 1987 */ 1988 blk_start_plug(&plug); 1989 do { 1990 io = crypt_io_from_node(rb_first(&write_tree)); 1991 rb_erase(&io->rb_node, &write_tree); 1992 kcryptd_io_write(io); 1993 cond_resched(); 1994 } while (!RB_EMPTY_ROOT(&write_tree)); 1995 blk_finish_plug(&plug); 1996 } 1997 return 0; 1998 } 1999 2000 static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async) 2001 { 2002 struct bio *clone = io->ctx.bio_out; 2003 struct crypt_config *cc = io->cc; 2004 unsigned long flags; 2005 sector_t sector; 2006 struct rb_node **rbp, *parent; 2007 2008 if (unlikely(io->error)) { 2009 crypt_free_buffer_pages(cc, clone); 2010 bio_put(clone); 2011 crypt_dec_pending(io); 2012 return; 2013 } 2014 2015 /* crypt_convert should have filled the clone bio */ 2016 BUG_ON(io->ctx.iter_out.bi_size); 2017 2018 clone->bi_iter.bi_sector = cc->start + io->sector; 2019 2020 if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) || 2021 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) { 2022 dm_submit_bio_remap(io->base_bio, clone); 2023 return; 2024 } 2025 2026 spin_lock_irqsave(&cc->write_thread_lock, flags); 2027 if (RB_EMPTY_ROOT(&cc->write_tree)) 2028 wake_up_process(cc->write_thread); 2029 rbp = &cc->write_tree.rb_node; 2030 parent = NULL; 2031 sector = io->sector; 2032 while (*rbp) { 2033 parent = *rbp; 2034 if (sector < crypt_io_from_node(parent)->sector) 2035 rbp = &(*rbp)->rb_left; 2036 else 2037 rbp = &(*rbp)->rb_right; 2038 } 2039 rb_link_node(&io->rb_node, parent, rbp); 2040 rb_insert_color(&io->rb_node, &cc->write_tree); 2041 spin_unlock_irqrestore(&cc->write_thread_lock, flags); 2042 } 2043 2044 static bool kcryptd_crypt_write_inline(struct crypt_config *cc, 2045 struct convert_context *ctx) 2046 2047 { 2048 if (!test_bit(DM_CRYPT_WRITE_INLINE, &cc->flags)) 2049 return false; 2050 2051 /* 2052 * Note: zone append writes (REQ_OP_ZONE_APPEND) do not have ordering 2053 * constraints so they do not need to be issued inline by 2054 * kcryptd_crypt_write_convert(). 2055 */ 2056 switch (bio_op(ctx->bio_in)) { 2057 case REQ_OP_WRITE: 2058 case REQ_OP_WRITE_ZEROES: 2059 return true; 2060 default: 2061 return false; 2062 } 2063 } 2064 2065 static void kcryptd_crypt_write_continue(struct work_struct *work) 2066 { 2067 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2068 struct crypt_config *cc = io->cc; 2069 struct convert_context *ctx = &io->ctx; 2070 int crypt_finished; 2071 sector_t sector = io->sector; 2072 blk_status_t r; 2073 2074 wait_for_completion(&ctx->restart); 2075 reinit_completion(&ctx->restart); 2076 2077 r = crypt_convert(cc, &io->ctx, true, false); 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 crypt_dec_pending(io); 2094 } 2095 2096 static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) 2097 { 2098 struct crypt_config *cc = io->cc; 2099 struct convert_context *ctx = &io->ctx; 2100 struct bio *clone; 2101 int crypt_finished; 2102 sector_t sector = io->sector; 2103 blk_status_t r; 2104 2105 /* 2106 * Prevent io from disappearing until this function completes. 2107 */ 2108 crypt_inc_pending(io); 2109 crypt_convert_init(cc, ctx, NULL, io->base_bio, sector); 2110 2111 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size); 2112 if (unlikely(!clone)) { 2113 io->error = BLK_STS_IOERR; 2114 goto dec; 2115 } 2116 2117 io->ctx.bio_out = clone; 2118 io->ctx.iter_out = clone->bi_iter; 2119 2120 if (crypt_integrity_aead(cc)) { 2121 bio_copy_data(clone, io->base_bio); 2122 io->ctx.bio_in = clone; 2123 io->ctx.iter_in = clone->bi_iter; 2124 } 2125 2126 sector += bio_sectors(clone); 2127 2128 crypt_inc_pending(io); 2129 r = crypt_convert(cc, ctx, 2130 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags), true); 2131 /* 2132 * Crypto API backlogged the request, because its queue was full 2133 * and we're in softirq context, so continue from a workqueue 2134 * (TODO: is it actually possible to be in softirq in the write path?) 2135 */ 2136 if (r == BLK_STS_DEV_RESOURCE) { 2137 INIT_WORK(&io->work, kcryptd_crypt_write_continue); 2138 queue_work(cc->crypt_queue, &io->work); 2139 return; 2140 } 2141 if (r) 2142 io->error = r; 2143 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2144 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2145 /* Wait for completion signaled by kcryptd_async_done() */ 2146 wait_for_completion(&ctx->restart); 2147 crypt_finished = 1; 2148 } 2149 2150 /* Encryption was already finished, submit io now */ 2151 if (crypt_finished) { 2152 kcryptd_crypt_write_io_submit(io, 0); 2153 io->sector = sector; 2154 } 2155 2156 dec: 2157 crypt_dec_pending(io); 2158 } 2159 2160 static void kcryptd_crypt_read_done(struct dm_crypt_io *io) 2161 { 2162 if (io->ctx.aead_recheck) { 2163 if (!io->error) { 2164 io->ctx.bio_in->bi_iter = io->saved_bi_iter; 2165 bio_copy_data(io->base_bio, io->ctx.bio_in); 2166 } 2167 crypt_free_buffer_pages(io->cc, io->ctx.bio_in); 2168 bio_put(io->ctx.bio_in); 2169 } 2170 crypt_dec_pending(io); 2171 } 2172 2173 static void kcryptd_crypt_read_continue(struct work_struct *work) 2174 { 2175 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2176 struct crypt_config *cc = io->cc; 2177 blk_status_t r; 2178 2179 wait_for_completion(&io->ctx.restart); 2180 reinit_completion(&io->ctx.restart); 2181 2182 r = crypt_convert(cc, &io->ctx, true, false); 2183 if (r) 2184 io->error = r; 2185 2186 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2187 kcryptd_crypt_read_done(io); 2188 2189 crypt_dec_pending(io); 2190 } 2191 2192 static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) 2193 { 2194 struct crypt_config *cc = io->cc; 2195 blk_status_t r; 2196 2197 crypt_inc_pending(io); 2198 2199 if (io->ctx.aead_recheck) { 2200 io->ctx.cc_sector = io->sector + cc->iv_offset; 2201 r = crypt_convert(cc, &io->ctx, 2202 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true); 2203 } else { 2204 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, 2205 io->sector); 2206 2207 r = crypt_convert(cc, &io->ctx, 2208 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true); 2209 } 2210 /* 2211 * Crypto API backlogged the request, because its queue was full 2212 * and we're in softirq context, so continue from a workqueue 2213 */ 2214 if (r == BLK_STS_DEV_RESOURCE) { 2215 INIT_WORK(&io->work, kcryptd_crypt_read_continue); 2216 queue_work(cc->crypt_queue, &io->work); 2217 return; 2218 } 2219 if (r) 2220 io->error = r; 2221 2222 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2223 kcryptd_crypt_read_done(io); 2224 2225 crypt_dec_pending(io); 2226 } 2227 2228 static void kcryptd_async_done(void *data, int error) 2229 { 2230 struct dm_crypt_request *dmreq = data; 2231 struct convert_context *ctx = dmreq->ctx; 2232 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 2233 struct crypt_config *cc = io->cc; 2234 2235 /* 2236 * A request from crypto driver backlog is going to be processed now, 2237 * finish the completion and continue in crypt_convert(). 2238 * (Callback will be called for the second time for this request.) 2239 */ 2240 if (error == -EINPROGRESS) { 2241 complete(&ctx->restart); 2242 return; 2243 } 2244 2245 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post) 2246 error = cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq); 2247 2248 if (error == -EBADMSG) { 2249 sector_t s = le64_to_cpu(*org_sector_of_dmreq(cc, dmreq)); 2250 2251 ctx->aead_failed = true; 2252 if (ctx->aead_recheck) { 2253 DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu", 2254 ctx->bio_in->bi_bdev, s); 2255 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead", 2256 ctx->bio_in, s, 0); 2257 } 2258 io->error = BLK_STS_PROTECTION; 2259 } else if (error < 0) 2260 io->error = BLK_STS_IOERR; 2261 2262 crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio); 2263 2264 if (!atomic_dec_and_test(&ctx->cc_pending)) 2265 return; 2266 2267 /* 2268 * The request is fully completed: for inline writes, let 2269 * kcryptd_crypt_write_convert() do the IO submission. 2270 */ 2271 if (bio_data_dir(io->base_bio) == READ) { 2272 kcryptd_crypt_read_done(io); 2273 return; 2274 } 2275 2276 if (kcryptd_crypt_write_inline(cc, ctx)) { 2277 complete(&ctx->restart); 2278 return; 2279 } 2280 2281 kcryptd_crypt_write_io_submit(io, 1); 2282 } 2283 2284 static void kcryptd_crypt(struct work_struct *work) 2285 { 2286 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2287 2288 if (bio_data_dir(io->base_bio) == READ) 2289 kcryptd_crypt_read_convert(io); 2290 else 2291 kcryptd_crypt_write_convert(io); 2292 } 2293 2294 static void kcryptd_queue_crypt(struct dm_crypt_io *io) 2295 { 2296 struct crypt_config *cc = io->cc; 2297 2298 if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) || 2299 (bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) { 2300 /* 2301 * in_hardirq(): Crypto API's skcipher_walk_first() refuses to work in hard IRQ context. 2302 * irqs_disabled(): the kernel may run some IO completion from the idle thread, but 2303 * it is being executed with irqs disabled. 2304 */ 2305 if (!(in_hardirq() || irqs_disabled())) { 2306 kcryptd_crypt(&io->work); 2307 return; 2308 } 2309 } 2310 2311 INIT_WORK(&io->work, kcryptd_crypt); 2312 queue_work(cc->crypt_queue, &io->work); 2313 } 2314 2315 static void crypt_free_tfms_aead(struct crypt_config *cc) 2316 { 2317 if (!cc->cipher_tfm.tfms_aead) 2318 return; 2319 2320 if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2321 crypto_free_aead(cc->cipher_tfm.tfms_aead[0]); 2322 cc->cipher_tfm.tfms_aead[0] = NULL; 2323 } 2324 2325 kfree(cc->cipher_tfm.tfms_aead); 2326 cc->cipher_tfm.tfms_aead = NULL; 2327 } 2328 2329 static void crypt_free_tfms_skcipher(struct crypt_config *cc) 2330 { 2331 unsigned int i; 2332 2333 if (!cc->cipher_tfm.tfms) 2334 return; 2335 2336 for (i = 0; i < cc->tfms_count; i++) 2337 if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) { 2338 crypto_free_skcipher(cc->cipher_tfm.tfms[i]); 2339 cc->cipher_tfm.tfms[i] = NULL; 2340 } 2341 2342 kfree(cc->cipher_tfm.tfms); 2343 cc->cipher_tfm.tfms = NULL; 2344 } 2345 2346 static void crypt_free_tfms(struct crypt_config *cc) 2347 { 2348 if (crypt_integrity_aead(cc)) 2349 crypt_free_tfms_aead(cc); 2350 else 2351 crypt_free_tfms_skcipher(cc); 2352 } 2353 2354 static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode) 2355 { 2356 unsigned int i; 2357 int err; 2358 2359 cc->cipher_tfm.tfms = kcalloc(cc->tfms_count, 2360 sizeof(struct crypto_skcipher *), 2361 GFP_KERNEL); 2362 if (!cc->cipher_tfm.tfms) 2363 return -ENOMEM; 2364 2365 for (i = 0; i < cc->tfms_count; i++) { 2366 cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0, 2367 CRYPTO_ALG_ALLOCATES_MEMORY); 2368 if (IS_ERR(cc->cipher_tfm.tfms[i])) { 2369 err = PTR_ERR(cc->cipher_tfm.tfms[i]); 2370 crypt_free_tfms(cc); 2371 return err; 2372 } 2373 } 2374 2375 /* 2376 * dm-crypt performance can vary greatly depending on which crypto 2377 * algorithm implementation is used. Help people debug performance 2378 * problems by logging the ->cra_driver_name. 2379 */ 2380 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2381 crypto_skcipher_alg(any_tfm(cc))->base.cra_driver_name); 2382 return 0; 2383 } 2384 2385 static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode) 2386 { 2387 int err; 2388 2389 cc->cipher_tfm.tfms = kmalloc(sizeof(struct crypto_aead *), GFP_KERNEL); 2390 if (!cc->cipher_tfm.tfms) 2391 return -ENOMEM; 2392 2393 cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0, 2394 CRYPTO_ALG_ALLOCATES_MEMORY); 2395 if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2396 err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]); 2397 crypt_free_tfms(cc); 2398 return err; 2399 } 2400 2401 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2402 crypto_aead_alg(any_tfm_aead(cc))->base.cra_driver_name); 2403 return 0; 2404 } 2405 2406 static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode) 2407 { 2408 if (crypt_integrity_aead(cc)) 2409 return crypt_alloc_tfms_aead(cc, ciphermode); 2410 else 2411 return crypt_alloc_tfms_skcipher(cc, ciphermode); 2412 } 2413 2414 static unsigned int crypt_subkey_size(struct crypt_config *cc) 2415 { 2416 return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count); 2417 } 2418 2419 static unsigned int crypt_authenckey_size(struct crypt_config *cc) 2420 { 2421 return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param)); 2422 } 2423 2424 /* 2425 * If AEAD is composed like authenc(hmac(sha256),xts(aes)), 2426 * the key must be for some reason in special format. 2427 * This funcion converts cc->key to this special format. 2428 */ 2429 static void crypt_copy_authenckey(char *p, const void *key, 2430 unsigned int enckeylen, unsigned int authkeylen) 2431 { 2432 struct crypto_authenc_key_param *param; 2433 struct rtattr *rta; 2434 2435 rta = (struct rtattr *)p; 2436 param = RTA_DATA(rta); 2437 param->enckeylen = cpu_to_be32(enckeylen); 2438 rta->rta_len = RTA_LENGTH(sizeof(*param)); 2439 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; 2440 p += RTA_SPACE(sizeof(*param)); 2441 memcpy(p, key + enckeylen, authkeylen); 2442 p += authkeylen; 2443 memcpy(p, key, enckeylen); 2444 } 2445 2446 static int crypt_setkey(struct crypt_config *cc) 2447 { 2448 unsigned int subkey_size; 2449 int err = 0, i, r; 2450 2451 /* Ignore extra keys (which are used for IV etc) */ 2452 subkey_size = crypt_subkey_size(cc); 2453 2454 if (crypt_integrity_hmac(cc)) { 2455 if (subkey_size < cc->key_mac_size) 2456 return -EINVAL; 2457 2458 crypt_copy_authenckey(cc->authenc_key, cc->key, 2459 subkey_size - cc->key_mac_size, 2460 cc->key_mac_size); 2461 } 2462 2463 for (i = 0; i < cc->tfms_count; i++) { 2464 if (crypt_integrity_hmac(cc)) 2465 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2466 cc->authenc_key, crypt_authenckey_size(cc)); 2467 else if (crypt_integrity_aead(cc)) 2468 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2469 cc->key + (i * subkey_size), 2470 subkey_size); 2471 else 2472 r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i], 2473 cc->key + (i * subkey_size), 2474 subkey_size); 2475 if (r) 2476 err = r; 2477 } 2478 2479 if (crypt_integrity_hmac(cc)) 2480 memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc)); 2481 2482 return err; 2483 } 2484 2485 #ifdef CONFIG_KEYS 2486 2487 static bool contains_whitespace(const char *str) 2488 { 2489 while (*str) 2490 if (isspace(*str++)) 2491 return true; 2492 return false; 2493 } 2494 2495 static int set_key_user(struct crypt_config *cc, struct key *key) 2496 { 2497 const struct user_key_payload *ukp; 2498 2499 ukp = user_key_payload_locked(key); 2500 if (!ukp) 2501 return -EKEYREVOKED; 2502 2503 if (cc->key_size != ukp->datalen) 2504 return -EINVAL; 2505 2506 memcpy(cc->key, ukp->data, cc->key_size); 2507 2508 return 0; 2509 } 2510 2511 static int set_key_encrypted(struct crypt_config *cc, struct key *key) 2512 { 2513 const struct encrypted_key_payload *ekp; 2514 2515 ekp = key->payload.data[0]; 2516 if (!ekp) 2517 return -EKEYREVOKED; 2518 2519 if (cc->key_size != ekp->decrypted_datalen) 2520 return -EINVAL; 2521 2522 memcpy(cc->key, ekp->decrypted_data, cc->key_size); 2523 2524 return 0; 2525 } 2526 2527 static int set_key_trusted(struct crypt_config *cc, struct key *key) 2528 { 2529 const struct trusted_key_payload *tkp; 2530 2531 tkp = key->payload.data[0]; 2532 if (!tkp) 2533 return -EKEYREVOKED; 2534 2535 if (cc->key_size != tkp->key_len) 2536 return -EINVAL; 2537 2538 memcpy(cc->key, tkp->key, cc->key_size); 2539 2540 return 0; 2541 } 2542 2543 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2544 { 2545 char *new_key_string, *key_desc; 2546 int ret; 2547 struct key_type *type; 2548 struct key *key; 2549 int (*set_key)(struct crypt_config *cc, struct key *key); 2550 2551 /* 2552 * Reject key_string with whitespace. dm core currently lacks code for 2553 * proper whitespace escaping in arguments on DM_TABLE_STATUS path. 2554 */ 2555 if (contains_whitespace(key_string)) { 2556 DMERR("whitespace chars not allowed in key string"); 2557 return -EINVAL; 2558 } 2559 2560 /* look for next ':' separating key_type from key_description */ 2561 key_desc = strchr(key_string, ':'); 2562 if (!key_desc || key_desc == key_string || !strlen(key_desc + 1)) 2563 return -EINVAL; 2564 2565 if (!strncmp(key_string, "logon:", key_desc - key_string + 1)) { 2566 type = &key_type_logon; 2567 set_key = set_key_user; 2568 } else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) { 2569 type = &key_type_user; 2570 set_key = set_key_user; 2571 } else if (IS_ENABLED(CONFIG_ENCRYPTED_KEYS) && 2572 !strncmp(key_string, "encrypted:", key_desc - key_string + 1)) { 2573 type = &key_type_encrypted; 2574 set_key = set_key_encrypted; 2575 } else if (IS_ENABLED(CONFIG_TRUSTED_KEYS) && 2576 !strncmp(key_string, "trusted:", key_desc - key_string + 1)) { 2577 type = &key_type_trusted; 2578 set_key = set_key_trusted; 2579 } else { 2580 return -EINVAL; 2581 } 2582 2583 new_key_string = kstrdup(key_string, GFP_KERNEL); 2584 if (!new_key_string) 2585 return -ENOMEM; 2586 2587 key = request_key(type, key_desc + 1, NULL); 2588 if (IS_ERR(key)) { 2589 kfree_sensitive(new_key_string); 2590 return PTR_ERR(key); 2591 } 2592 2593 down_read(&key->sem); 2594 2595 ret = set_key(cc, key); 2596 if (ret < 0) { 2597 up_read(&key->sem); 2598 key_put(key); 2599 kfree_sensitive(new_key_string); 2600 return ret; 2601 } 2602 2603 up_read(&key->sem); 2604 key_put(key); 2605 2606 /* clear the flag since following operations may invalidate previously valid key */ 2607 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2608 2609 ret = crypt_setkey(cc); 2610 2611 if (!ret) { 2612 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2613 kfree_sensitive(cc->key_string); 2614 cc->key_string = new_key_string; 2615 } else 2616 kfree_sensitive(new_key_string); 2617 2618 return ret; 2619 } 2620 2621 static int get_key_size(char **key_string) 2622 { 2623 char *colon, dummy; 2624 int ret; 2625 2626 if (*key_string[0] != ':') 2627 return strlen(*key_string) >> 1; 2628 2629 /* look for next ':' in key string */ 2630 colon = strpbrk(*key_string + 1, ":"); 2631 if (!colon) 2632 return -EINVAL; 2633 2634 if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':') 2635 return -EINVAL; 2636 2637 *key_string = colon; 2638 2639 /* remaining key string should be :<logon|user>:<key_desc> */ 2640 2641 return ret; 2642 } 2643 2644 #else 2645 2646 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2647 { 2648 return -EINVAL; 2649 } 2650 2651 static int get_key_size(char **key_string) 2652 { 2653 return (*key_string[0] == ':') ? -EINVAL : (int)(strlen(*key_string) >> 1); 2654 } 2655 2656 #endif /* CONFIG_KEYS */ 2657 2658 static int crypt_set_key(struct crypt_config *cc, char *key) 2659 { 2660 int r = -EINVAL; 2661 int key_string_len = strlen(key); 2662 2663 /* Hyphen (which gives a key_size of zero) means there is no key. */ 2664 if (!cc->key_size && strcmp(key, "-")) 2665 goto out; 2666 2667 /* ':' means the key is in kernel keyring, short-circuit normal key processing */ 2668 if (key[0] == ':') { 2669 r = crypt_set_keyring_key(cc, key + 1); 2670 goto out; 2671 } 2672 2673 /* clear the flag since following operations may invalidate previously valid key */ 2674 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2675 2676 /* wipe references to any kernel keyring key */ 2677 kfree_sensitive(cc->key_string); 2678 cc->key_string = NULL; 2679 2680 /* Decode key from its hex representation. */ 2681 if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0) 2682 goto out; 2683 2684 r = crypt_setkey(cc); 2685 if (!r) 2686 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2687 2688 out: 2689 /* Hex key string not needed after here, so wipe it. */ 2690 memset(key, '0', key_string_len); 2691 2692 return r; 2693 } 2694 2695 static int crypt_wipe_key(struct crypt_config *cc) 2696 { 2697 int r; 2698 2699 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2700 get_random_bytes(&cc->key, cc->key_size); 2701 2702 /* Wipe IV private keys */ 2703 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) { 2704 r = cc->iv_gen_ops->wipe(cc); 2705 if (r) 2706 return r; 2707 } 2708 2709 kfree_sensitive(cc->key_string); 2710 cc->key_string = NULL; 2711 r = crypt_setkey(cc); 2712 memset(&cc->key, 0, cc->key_size * sizeof(u8)); 2713 2714 return r; 2715 } 2716 2717 static void crypt_calculate_pages_per_client(void) 2718 { 2719 unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100; 2720 2721 if (!dm_crypt_clients_n) 2722 return; 2723 2724 pages /= dm_crypt_clients_n; 2725 if (pages < DM_CRYPT_MIN_PAGES_PER_CLIENT) 2726 pages = DM_CRYPT_MIN_PAGES_PER_CLIENT; 2727 dm_crypt_pages_per_client = pages; 2728 } 2729 2730 static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data) 2731 { 2732 struct crypt_config *cc = pool_data; 2733 struct page *page; 2734 2735 /* 2736 * Note, percpu_counter_read_positive() may over (and under) estimate 2737 * the current usage by at most (batch - 1) * num_online_cpus() pages, 2738 * but avoids potential spinlock contention of an exact result. 2739 */ 2740 if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) >= dm_crypt_pages_per_client) && 2741 likely(gfp_mask & __GFP_NORETRY)) 2742 return NULL; 2743 2744 page = alloc_page(gfp_mask); 2745 if (likely(page != NULL)) 2746 percpu_counter_add(&cc->n_allocated_pages, 1); 2747 2748 return page; 2749 } 2750 2751 static void crypt_page_free(void *page, void *pool_data) 2752 { 2753 struct crypt_config *cc = pool_data; 2754 2755 __free_page(page); 2756 percpu_counter_sub(&cc->n_allocated_pages, 1); 2757 } 2758 2759 static void crypt_dtr(struct dm_target *ti) 2760 { 2761 struct crypt_config *cc = ti->private; 2762 2763 ti->private = NULL; 2764 2765 if (!cc) 2766 return; 2767 2768 if (cc->write_thread) 2769 kthread_stop(cc->write_thread); 2770 2771 if (cc->io_queue) 2772 destroy_workqueue(cc->io_queue); 2773 if (cc->crypt_queue) 2774 destroy_workqueue(cc->crypt_queue); 2775 2776 crypt_free_tfms(cc); 2777 2778 bioset_exit(&cc->bs); 2779 2780 mempool_exit(&cc->page_pool); 2781 mempool_exit(&cc->req_pool); 2782 mempool_exit(&cc->tag_pool); 2783 2784 WARN_ON(percpu_counter_sum(&cc->n_allocated_pages) != 0); 2785 percpu_counter_destroy(&cc->n_allocated_pages); 2786 2787 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) 2788 cc->iv_gen_ops->dtr(cc); 2789 2790 if (cc->dev) 2791 dm_put_device(ti, cc->dev); 2792 2793 kfree_sensitive(cc->cipher_string); 2794 kfree_sensitive(cc->key_string); 2795 kfree_sensitive(cc->cipher_auth); 2796 kfree_sensitive(cc->authenc_key); 2797 2798 mutex_destroy(&cc->bio_alloc_lock); 2799 2800 /* Must zero key material before freeing */ 2801 kfree_sensitive(cc); 2802 2803 spin_lock(&dm_crypt_clients_lock); 2804 WARN_ON(!dm_crypt_clients_n); 2805 dm_crypt_clients_n--; 2806 crypt_calculate_pages_per_client(); 2807 spin_unlock(&dm_crypt_clients_lock); 2808 2809 dm_audit_log_dtr(DM_MSG_PREFIX, ti, 1); 2810 } 2811 2812 static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode) 2813 { 2814 struct crypt_config *cc = ti->private; 2815 2816 if (crypt_integrity_aead(cc)) 2817 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2818 else 2819 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2820 2821 if (cc->iv_size) 2822 /* at least a 64 bit sector number should fit in our buffer */ 2823 cc->iv_size = max(cc->iv_size, 2824 (unsigned int)(sizeof(u64) / sizeof(u8))); 2825 else if (ivmode) { 2826 DMWARN("Selected cipher does not support IVs"); 2827 ivmode = NULL; 2828 } 2829 2830 /* Choose ivmode, see comments at iv code. */ 2831 if (ivmode == NULL) 2832 cc->iv_gen_ops = NULL; 2833 else if (strcmp(ivmode, "plain") == 0) 2834 cc->iv_gen_ops = &crypt_iv_plain_ops; 2835 else if (strcmp(ivmode, "plain64") == 0) 2836 cc->iv_gen_ops = &crypt_iv_plain64_ops; 2837 else if (strcmp(ivmode, "plain64be") == 0) 2838 cc->iv_gen_ops = &crypt_iv_plain64be_ops; 2839 else if (strcmp(ivmode, "essiv") == 0) 2840 cc->iv_gen_ops = &crypt_iv_essiv_ops; 2841 else if (strcmp(ivmode, "benbi") == 0) 2842 cc->iv_gen_ops = &crypt_iv_benbi_ops; 2843 else if (strcmp(ivmode, "null") == 0) 2844 cc->iv_gen_ops = &crypt_iv_null_ops; 2845 else if (strcmp(ivmode, "eboiv") == 0) 2846 cc->iv_gen_ops = &crypt_iv_eboiv_ops; 2847 else if (strcmp(ivmode, "elephant") == 0) { 2848 cc->iv_gen_ops = &crypt_iv_elephant_ops; 2849 cc->key_parts = 2; 2850 cc->key_extra_size = cc->key_size / 2; 2851 if (cc->key_extra_size > ELEPHANT_MAX_KEY_SIZE) 2852 return -EINVAL; 2853 set_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags); 2854 } else if (strcmp(ivmode, "lmk") == 0) { 2855 cc->iv_gen_ops = &crypt_iv_lmk_ops; 2856 /* 2857 * Version 2 and 3 is recognised according 2858 * to length of provided multi-key string. 2859 * If present (version 3), last key is used as IV seed. 2860 * All keys (including IV seed) are always the same size. 2861 */ 2862 if (cc->key_size % cc->key_parts) { 2863 cc->key_parts++; 2864 cc->key_extra_size = cc->key_size / cc->key_parts; 2865 } 2866 } else if (strcmp(ivmode, "tcw") == 0) { 2867 cc->iv_gen_ops = &crypt_iv_tcw_ops; 2868 cc->key_parts += 2; /* IV + whitening */ 2869 cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE; 2870 } else if (strcmp(ivmode, "random") == 0) { 2871 cc->iv_gen_ops = &crypt_iv_random_ops; 2872 /* Need storage space in integrity fields. */ 2873 cc->integrity_iv_size = cc->iv_size; 2874 } else { 2875 ti->error = "Invalid IV mode"; 2876 return -EINVAL; 2877 } 2878 2879 return 0; 2880 } 2881 2882 /* 2883 * Workaround to parse HMAC algorithm from AEAD crypto API spec. 2884 * The HMAC is needed to calculate tag size (HMAC digest size). 2885 * This should be probably done by crypto-api calls (once available...) 2886 */ 2887 static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api) 2888 { 2889 char *start, *end, *mac_alg = NULL; 2890 struct crypto_ahash *mac; 2891 2892 if (!strstarts(cipher_api, "authenc(")) 2893 return 0; 2894 2895 start = strchr(cipher_api, '('); 2896 end = strchr(cipher_api, ','); 2897 if (!start || !end || ++start > end) 2898 return -EINVAL; 2899 2900 mac_alg = kzalloc(end - start + 1, GFP_KERNEL); 2901 if (!mac_alg) 2902 return -ENOMEM; 2903 strncpy(mac_alg, start, end - start); 2904 2905 mac = crypto_alloc_ahash(mac_alg, 0, CRYPTO_ALG_ALLOCATES_MEMORY); 2906 kfree(mac_alg); 2907 2908 if (IS_ERR(mac)) 2909 return PTR_ERR(mac); 2910 2911 cc->key_mac_size = crypto_ahash_digestsize(mac); 2912 crypto_free_ahash(mac); 2913 2914 cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL); 2915 if (!cc->authenc_key) 2916 return -ENOMEM; 2917 2918 return 0; 2919 } 2920 2921 static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key, 2922 char **ivmode, char **ivopts) 2923 { 2924 struct crypt_config *cc = ti->private; 2925 char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME]; 2926 int ret = -EINVAL; 2927 2928 cc->tfms_count = 1; 2929 2930 /* 2931 * New format (capi: prefix) 2932 * capi:cipher_api_spec-iv:ivopts 2933 */ 2934 tmp = &cipher_in[strlen("capi:")]; 2935 2936 /* Separate IV options if present, it can contain another '-' in hash name */ 2937 *ivopts = strrchr(tmp, ':'); 2938 if (*ivopts) { 2939 **ivopts = '\0'; 2940 (*ivopts)++; 2941 } 2942 /* Parse IV mode */ 2943 *ivmode = strrchr(tmp, '-'); 2944 if (*ivmode) { 2945 **ivmode = '\0'; 2946 (*ivmode)++; 2947 } 2948 /* The rest is crypto API spec */ 2949 cipher_api = tmp; 2950 2951 /* Alloc AEAD, can be used only in new format. */ 2952 if (crypt_integrity_aead(cc)) { 2953 ret = crypt_ctr_auth_cipher(cc, cipher_api); 2954 if (ret < 0) { 2955 ti->error = "Invalid AEAD cipher spec"; 2956 return ret; 2957 } 2958 } 2959 2960 if (*ivmode && !strcmp(*ivmode, "lmk")) 2961 cc->tfms_count = 64; 2962 2963 if (*ivmode && !strcmp(*ivmode, "essiv")) { 2964 if (!*ivopts) { 2965 ti->error = "Digest algorithm missing for ESSIV mode"; 2966 return -EINVAL; 2967 } 2968 ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)", 2969 cipher_api, *ivopts); 2970 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 2971 ti->error = "Cannot allocate cipher string"; 2972 return -ENOMEM; 2973 } 2974 cipher_api = buf; 2975 } 2976 2977 cc->key_parts = cc->tfms_count; 2978 2979 /* Allocate cipher */ 2980 ret = crypt_alloc_tfms(cc, cipher_api); 2981 if (ret < 0) { 2982 ti->error = "Error allocating crypto tfm"; 2983 return ret; 2984 } 2985 2986 if (crypt_integrity_aead(cc)) 2987 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2988 else 2989 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2990 2991 return 0; 2992 } 2993 2994 static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key, 2995 char **ivmode, char **ivopts) 2996 { 2997 struct crypt_config *cc = ti->private; 2998 char *tmp, *cipher, *chainmode, *keycount; 2999 char *cipher_api = NULL; 3000 int ret = -EINVAL; 3001 char dummy; 3002 3003 if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) { 3004 ti->error = "Bad cipher specification"; 3005 return -EINVAL; 3006 } 3007 3008 /* 3009 * Legacy dm-crypt cipher specification 3010 * cipher[:keycount]-mode-iv:ivopts 3011 */ 3012 tmp = cipher_in; 3013 keycount = strsep(&tmp, "-"); 3014 cipher = strsep(&keycount, ":"); 3015 3016 if (!keycount) 3017 cc->tfms_count = 1; 3018 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 || 3019 !is_power_of_2(cc->tfms_count)) { 3020 ti->error = "Bad cipher key count specification"; 3021 return -EINVAL; 3022 } 3023 cc->key_parts = cc->tfms_count; 3024 3025 chainmode = strsep(&tmp, "-"); 3026 *ivmode = strsep(&tmp, ":"); 3027 *ivopts = tmp; 3028 3029 /* 3030 * For compatibility with the original dm-crypt mapping format, if 3031 * only the cipher name is supplied, use cbc-plain. 3032 */ 3033 if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) { 3034 chainmode = "cbc"; 3035 *ivmode = "plain"; 3036 } 3037 3038 if (strcmp(chainmode, "ecb") && !*ivmode) { 3039 ti->error = "IV mechanism required"; 3040 return -EINVAL; 3041 } 3042 3043 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL); 3044 if (!cipher_api) 3045 goto bad_mem; 3046 3047 if (*ivmode && !strcmp(*ivmode, "essiv")) { 3048 if (!*ivopts) { 3049 ti->error = "Digest algorithm missing for ESSIV mode"; 3050 kfree(cipher_api); 3051 return -EINVAL; 3052 } 3053 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 3054 "essiv(%s(%s),%s)", chainmode, cipher, *ivopts); 3055 } else { 3056 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 3057 "%s(%s)", chainmode, cipher); 3058 } 3059 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 3060 kfree(cipher_api); 3061 goto bad_mem; 3062 } 3063 3064 /* Allocate cipher */ 3065 ret = crypt_alloc_tfms(cc, cipher_api); 3066 if (ret < 0) { 3067 ti->error = "Error allocating crypto tfm"; 3068 kfree(cipher_api); 3069 return ret; 3070 } 3071 kfree(cipher_api); 3072 3073 return 0; 3074 bad_mem: 3075 ti->error = "Cannot allocate cipher strings"; 3076 return -ENOMEM; 3077 } 3078 3079 static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key) 3080 { 3081 struct crypt_config *cc = ti->private; 3082 char *ivmode = NULL, *ivopts = NULL; 3083 int ret; 3084 3085 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL); 3086 if (!cc->cipher_string) { 3087 ti->error = "Cannot allocate cipher strings"; 3088 return -ENOMEM; 3089 } 3090 3091 if (strstarts(cipher_in, "capi:")) 3092 ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts); 3093 else 3094 ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts); 3095 if (ret) 3096 return ret; 3097 3098 /* Initialize IV */ 3099 ret = crypt_ctr_ivmode(ti, ivmode); 3100 if (ret < 0) 3101 return ret; 3102 3103 /* Initialize and set key */ 3104 ret = crypt_set_key(cc, key); 3105 if (ret < 0) { 3106 ti->error = "Error decoding and setting key"; 3107 return ret; 3108 } 3109 3110 /* Allocate IV */ 3111 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) { 3112 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts); 3113 if (ret < 0) { 3114 ti->error = "Error creating IV"; 3115 return ret; 3116 } 3117 } 3118 3119 /* Initialize IV (set keys for ESSIV etc) */ 3120 if (cc->iv_gen_ops && cc->iv_gen_ops->init) { 3121 ret = cc->iv_gen_ops->init(cc); 3122 if (ret < 0) { 3123 ti->error = "Error initialising IV"; 3124 return ret; 3125 } 3126 } 3127 3128 /* wipe the kernel key payload copy */ 3129 if (cc->key_string) 3130 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3131 3132 return ret; 3133 } 3134 3135 static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv) 3136 { 3137 struct crypt_config *cc = ti->private; 3138 struct dm_arg_set as; 3139 static const struct dm_arg _args[] = { 3140 {0, 8, "Invalid number of feature args"}, 3141 }; 3142 unsigned int opt_params, val; 3143 const char *opt_string, *sval; 3144 char dummy; 3145 int ret; 3146 3147 /* Optional parameters */ 3148 as.argc = argc; 3149 as.argv = argv; 3150 3151 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error); 3152 if (ret) 3153 return ret; 3154 3155 while (opt_params--) { 3156 opt_string = dm_shift_arg(&as); 3157 if (!opt_string) { 3158 ti->error = "Not enough feature arguments"; 3159 return -EINVAL; 3160 } 3161 3162 if (!strcasecmp(opt_string, "allow_discards")) 3163 ti->num_discard_bios = 1; 3164 3165 else if (!strcasecmp(opt_string, "same_cpu_crypt")) 3166 set_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3167 3168 else if (!strcasecmp(opt_string, "submit_from_crypt_cpus")) 3169 set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3170 else if (!strcasecmp(opt_string, "no_read_workqueue")) 3171 set_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3172 else if (!strcasecmp(opt_string, "no_write_workqueue")) 3173 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3174 else if (sscanf(opt_string, "integrity:%u:", &val) == 1) { 3175 if (val == 0 || val > MAX_TAG_SIZE) { 3176 ti->error = "Invalid integrity arguments"; 3177 return -EINVAL; 3178 } 3179 cc->on_disk_tag_size = val; 3180 sval = strchr(opt_string + strlen("integrity:"), ':') + 1; 3181 if (!strcasecmp(sval, "aead")) { 3182 set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 3183 } else if (strcasecmp(sval, "none")) { 3184 ti->error = "Unknown integrity profile"; 3185 return -EINVAL; 3186 } 3187 3188 cc->cipher_auth = kstrdup(sval, GFP_KERNEL); 3189 if (!cc->cipher_auth) 3190 return -ENOMEM; 3191 } else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) { 3192 if (cc->sector_size < (1 << SECTOR_SHIFT) || 3193 cc->sector_size > 4096 || 3194 (cc->sector_size & (cc->sector_size - 1))) { 3195 ti->error = "Invalid feature value for sector_size"; 3196 return -EINVAL; 3197 } 3198 if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) { 3199 ti->error = "Device size is not multiple of sector_size feature"; 3200 return -EINVAL; 3201 } 3202 cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT; 3203 } else if (!strcasecmp(opt_string, "iv_large_sectors")) 3204 set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3205 else { 3206 ti->error = "Invalid feature arguments"; 3207 return -EINVAL; 3208 } 3209 } 3210 3211 return 0; 3212 } 3213 3214 #ifdef CONFIG_BLK_DEV_ZONED 3215 static int crypt_report_zones(struct dm_target *ti, 3216 struct dm_report_zones_args *args, unsigned int nr_zones) 3217 { 3218 struct crypt_config *cc = ti->private; 3219 3220 return dm_report_zones(cc->dev->bdev, cc->start, 3221 cc->start + dm_target_offset(ti, args->next_sector), 3222 args, nr_zones); 3223 } 3224 #else 3225 #define crypt_report_zones NULL 3226 #endif 3227 3228 /* 3229 * Construct an encryption mapping: 3230 * <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start> 3231 */ 3232 static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) 3233 { 3234 struct crypt_config *cc; 3235 const char *devname = dm_table_device_name(ti->table); 3236 int key_size; 3237 unsigned int align_mask; 3238 unsigned long long tmpll; 3239 int ret; 3240 size_t iv_size_padding, additional_req_size; 3241 char dummy; 3242 3243 if (argc < 5) { 3244 ti->error = "Not enough arguments"; 3245 return -EINVAL; 3246 } 3247 3248 key_size = get_key_size(&argv[1]); 3249 if (key_size < 0) { 3250 ti->error = "Cannot parse key size"; 3251 return -EINVAL; 3252 } 3253 3254 cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL); 3255 if (!cc) { 3256 ti->error = "Cannot allocate encryption context"; 3257 return -ENOMEM; 3258 } 3259 cc->key_size = key_size; 3260 cc->sector_size = (1 << SECTOR_SHIFT); 3261 cc->sector_shift = 0; 3262 3263 ti->private = cc; 3264 3265 spin_lock(&dm_crypt_clients_lock); 3266 dm_crypt_clients_n++; 3267 crypt_calculate_pages_per_client(); 3268 spin_unlock(&dm_crypt_clients_lock); 3269 3270 ret = percpu_counter_init(&cc->n_allocated_pages, 0, GFP_KERNEL); 3271 if (ret < 0) 3272 goto bad; 3273 3274 /* Optional parameters need to be read before cipher constructor */ 3275 if (argc > 5) { 3276 ret = crypt_ctr_optional(ti, argc - 5, &argv[5]); 3277 if (ret) 3278 goto bad; 3279 } 3280 3281 ret = crypt_ctr_cipher(ti, argv[0], argv[1]); 3282 if (ret < 0) 3283 goto bad; 3284 3285 if (crypt_integrity_aead(cc)) { 3286 cc->dmreq_start = sizeof(struct aead_request); 3287 cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc)); 3288 align_mask = crypto_aead_alignmask(any_tfm_aead(cc)); 3289 } else { 3290 cc->dmreq_start = sizeof(struct skcipher_request); 3291 cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc)); 3292 align_mask = crypto_skcipher_alignmask(any_tfm(cc)); 3293 } 3294 cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request)); 3295 3296 if (align_mask < CRYPTO_MINALIGN) { 3297 /* Allocate the padding exactly */ 3298 iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request)) 3299 & align_mask; 3300 } else { 3301 /* 3302 * If the cipher requires greater alignment than kmalloc 3303 * alignment, we don't know the exact position of the 3304 * initialization vector. We must assume worst case. 3305 */ 3306 iv_size_padding = align_mask; 3307 } 3308 3309 /* ...| IV + padding | original IV | original sec. number | bio tag offset | */ 3310 additional_req_size = sizeof(struct dm_crypt_request) + 3311 iv_size_padding + cc->iv_size + 3312 cc->iv_size + 3313 sizeof(uint64_t) + 3314 sizeof(unsigned int); 3315 3316 ret = mempool_init_kmalloc_pool(&cc->req_pool, MIN_IOS, cc->dmreq_start + additional_req_size); 3317 if (ret) { 3318 ti->error = "Cannot allocate crypt request mempool"; 3319 goto bad; 3320 } 3321 3322 cc->per_bio_data_size = ti->per_io_data_size = 3323 ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size, 3324 ARCH_DMA_MINALIGN); 3325 3326 ret = mempool_init(&cc->page_pool, BIO_MAX_VECS, crypt_page_alloc, crypt_page_free, cc); 3327 if (ret) { 3328 ti->error = "Cannot allocate page mempool"; 3329 goto bad; 3330 } 3331 3332 ret = bioset_init(&cc->bs, MIN_IOS, 0, BIOSET_NEED_BVECS); 3333 if (ret) { 3334 ti->error = "Cannot allocate crypt bioset"; 3335 goto bad; 3336 } 3337 3338 mutex_init(&cc->bio_alloc_lock); 3339 3340 ret = -EINVAL; 3341 if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) || 3342 (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) { 3343 ti->error = "Invalid iv_offset sector"; 3344 goto bad; 3345 } 3346 cc->iv_offset = tmpll; 3347 3348 ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev); 3349 if (ret) { 3350 ti->error = "Device lookup failed"; 3351 goto bad; 3352 } 3353 3354 ret = -EINVAL; 3355 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) { 3356 ti->error = "Invalid device sector"; 3357 goto bad; 3358 } 3359 cc->start = tmpll; 3360 3361 if (bdev_is_zoned(cc->dev->bdev)) { 3362 /* 3363 * For zoned block devices, we need to preserve the issuer write 3364 * ordering. To do so, disable write workqueues and force inline 3365 * encryption completion. 3366 */ 3367 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3368 set_bit(DM_CRYPT_WRITE_INLINE, &cc->flags); 3369 3370 /* 3371 * All zone append writes to a zone of a zoned block device will 3372 * have the same BIO sector, the start of the zone. When the 3373 * cypher IV mode uses sector values, all data targeting a 3374 * zone will be encrypted using the first sector numbers of the 3375 * zone. This will not result in write errors but will 3376 * cause most reads to fail as reads will use the sector values 3377 * for the actual data locations, resulting in IV mismatch. 3378 * To avoid this problem, ask DM core to emulate zone append 3379 * operations with regular writes. 3380 */ 3381 DMDEBUG("Zone append operations will be emulated"); 3382 ti->emulate_zone_append = true; 3383 } 3384 3385 if (crypt_integrity_aead(cc) || cc->integrity_iv_size) { 3386 ret = crypt_integrity_ctr(cc, ti); 3387 if (ret) 3388 goto bad; 3389 3390 cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->on_disk_tag_size; 3391 if (!cc->tag_pool_max_sectors) 3392 cc->tag_pool_max_sectors = 1; 3393 3394 ret = mempool_init_kmalloc_pool(&cc->tag_pool, MIN_IOS, 3395 cc->tag_pool_max_sectors * cc->on_disk_tag_size); 3396 if (ret) { 3397 ti->error = "Cannot allocate integrity tags mempool"; 3398 goto bad; 3399 } 3400 3401 cc->tag_pool_max_sectors <<= cc->sector_shift; 3402 } 3403 3404 ret = -ENOMEM; 3405 cc->io_queue = alloc_workqueue("kcryptd_io/%s", WQ_MEM_RECLAIM, 1, devname); 3406 if (!cc->io_queue) { 3407 ti->error = "Couldn't create kcryptd io queue"; 3408 goto bad; 3409 } 3410 3411 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3412 cc->crypt_queue = alloc_workqueue("kcryptd/%s", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 3413 1, devname); 3414 else 3415 cc->crypt_queue = alloc_workqueue("kcryptd/%s", 3416 WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND, 3417 num_online_cpus(), devname); 3418 if (!cc->crypt_queue) { 3419 ti->error = "Couldn't create kcryptd queue"; 3420 goto bad; 3421 } 3422 3423 spin_lock_init(&cc->write_thread_lock); 3424 cc->write_tree = RB_ROOT; 3425 3426 cc->write_thread = kthread_run(dmcrypt_write, cc, "dmcrypt_write/%s", devname); 3427 if (IS_ERR(cc->write_thread)) { 3428 ret = PTR_ERR(cc->write_thread); 3429 cc->write_thread = NULL; 3430 ti->error = "Couldn't spawn write thread"; 3431 goto bad; 3432 } 3433 3434 ti->num_flush_bios = 1; 3435 ti->limit_swap_bios = true; 3436 ti->accounts_remapped_io = true; 3437 3438 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 1); 3439 return 0; 3440 3441 bad: 3442 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 0); 3443 crypt_dtr(ti); 3444 return ret; 3445 } 3446 3447 static int crypt_map(struct dm_target *ti, struct bio *bio) 3448 { 3449 struct dm_crypt_io *io; 3450 struct crypt_config *cc = ti->private; 3451 3452 /* 3453 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues. 3454 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight 3455 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters 3456 */ 3457 if (unlikely(bio->bi_opf & REQ_PREFLUSH || 3458 bio_op(bio) == REQ_OP_DISCARD)) { 3459 bio_set_dev(bio, cc->dev->bdev); 3460 if (bio_sectors(bio)) 3461 bio->bi_iter.bi_sector = cc->start + 3462 dm_target_offset(ti, bio->bi_iter.bi_sector); 3463 return DM_MAPIO_REMAPPED; 3464 } 3465 3466 /* 3467 * Check if bio is too large, split as needed. 3468 */ 3469 if (unlikely(bio->bi_iter.bi_size > (BIO_MAX_VECS << PAGE_SHIFT)) && 3470 (bio_data_dir(bio) == WRITE || cc->on_disk_tag_size)) 3471 dm_accept_partial_bio(bio, ((BIO_MAX_VECS << PAGE_SHIFT) >> SECTOR_SHIFT)); 3472 3473 /* 3474 * Ensure that bio is a multiple of internal sector encryption size 3475 * and is aligned to this size as defined in IO hints. 3476 */ 3477 if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0)) 3478 return DM_MAPIO_KILL; 3479 3480 if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1))) 3481 return DM_MAPIO_KILL; 3482 3483 io = dm_per_bio_data(bio, cc->per_bio_data_size); 3484 crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector)); 3485 3486 if (cc->on_disk_tag_size) { 3487 unsigned int tag_len = cc->on_disk_tag_size * (bio_sectors(bio) >> cc->sector_shift); 3488 3489 if (unlikely(tag_len > KMALLOC_MAX_SIZE)) 3490 io->integrity_metadata = NULL; 3491 else 3492 io->integrity_metadata = kmalloc(tag_len, GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN); 3493 3494 if (unlikely(!io->integrity_metadata)) { 3495 if (bio_sectors(bio) > cc->tag_pool_max_sectors) 3496 dm_accept_partial_bio(bio, cc->tag_pool_max_sectors); 3497 io->integrity_metadata = mempool_alloc(&cc->tag_pool, GFP_NOIO); 3498 io->integrity_metadata_from_pool = true; 3499 } 3500 } 3501 3502 if (crypt_integrity_aead(cc)) 3503 io->ctx.r.req_aead = (struct aead_request *)(io + 1); 3504 else 3505 io->ctx.r.req = (struct skcipher_request *)(io + 1); 3506 3507 if (bio_data_dir(io->base_bio) == READ) { 3508 if (kcryptd_io_read(io, CRYPT_MAP_READ_GFP)) 3509 kcryptd_queue_read(io); 3510 } else 3511 kcryptd_queue_crypt(io); 3512 3513 return DM_MAPIO_SUBMITTED; 3514 } 3515 3516 static char hex2asc(unsigned char c) 3517 { 3518 return c + '0' + ((unsigned int)(9 - c) >> 4 & 0x27); 3519 } 3520 3521 static void crypt_status(struct dm_target *ti, status_type_t type, 3522 unsigned int status_flags, char *result, unsigned int maxlen) 3523 { 3524 struct crypt_config *cc = ti->private; 3525 unsigned int i, sz = 0; 3526 int num_feature_args = 0; 3527 3528 switch (type) { 3529 case STATUSTYPE_INFO: 3530 result[0] = '\0'; 3531 break; 3532 3533 case STATUSTYPE_TABLE: 3534 DMEMIT("%s ", cc->cipher_string); 3535 3536 if (cc->key_size > 0) { 3537 if (cc->key_string) 3538 DMEMIT(":%u:%s", cc->key_size, cc->key_string); 3539 else { 3540 for (i = 0; i < cc->key_size; i++) { 3541 DMEMIT("%c%c", hex2asc(cc->key[i] >> 4), 3542 hex2asc(cc->key[i] & 0xf)); 3543 } 3544 } 3545 } else 3546 DMEMIT("-"); 3547 3548 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, 3549 cc->dev->name, (unsigned long long)cc->start); 3550 3551 num_feature_args += !!ti->num_discard_bios; 3552 num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3553 num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3554 num_feature_args += test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3555 num_feature_args += test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3556 num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT); 3557 num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3558 if (cc->on_disk_tag_size) 3559 num_feature_args++; 3560 if (num_feature_args) { 3561 DMEMIT(" %d", num_feature_args); 3562 if (ti->num_discard_bios) 3563 DMEMIT(" allow_discards"); 3564 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3565 DMEMIT(" same_cpu_crypt"); 3566 if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) 3567 DMEMIT(" submit_from_crypt_cpus"); 3568 if (test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) 3569 DMEMIT(" no_read_workqueue"); 3570 if (test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) 3571 DMEMIT(" no_write_workqueue"); 3572 if (cc->on_disk_tag_size) 3573 DMEMIT(" integrity:%u:%s", cc->on_disk_tag_size, cc->cipher_auth); 3574 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3575 DMEMIT(" sector_size:%d", cc->sector_size); 3576 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 3577 DMEMIT(" iv_large_sectors"); 3578 } 3579 break; 3580 3581 case STATUSTYPE_IMA: 3582 DMEMIT_TARGET_NAME_VERSION(ti->type); 3583 DMEMIT(",allow_discards=%c", ti->num_discard_bios ? 'y' : 'n'); 3584 DMEMIT(",same_cpu_crypt=%c", test_bit(DM_CRYPT_SAME_CPU, &cc->flags) ? 'y' : 'n'); 3585 DMEMIT(",submit_from_crypt_cpus=%c", test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags) ? 3586 'y' : 'n'); 3587 DMEMIT(",no_read_workqueue=%c", test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags) ? 3588 'y' : 'n'); 3589 DMEMIT(",no_write_workqueue=%c", test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags) ? 3590 'y' : 'n'); 3591 DMEMIT(",iv_large_sectors=%c", test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags) ? 3592 'y' : 'n'); 3593 3594 if (cc->on_disk_tag_size) 3595 DMEMIT(",integrity_tag_size=%u,cipher_auth=%s", 3596 cc->on_disk_tag_size, cc->cipher_auth); 3597 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3598 DMEMIT(",sector_size=%d", cc->sector_size); 3599 if (cc->cipher_string) 3600 DMEMIT(",cipher_string=%s", cc->cipher_string); 3601 3602 DMEMIT(",key_size=%u", cc->key_size); 3603 DMEMIT(",key_parts=%u", cc->key_parts); 3604 DMEMIT(",key_extra_size=%u", cc->key_extra_size); 3605 DMEMIT(",key_mac_size=%u", cc->key_mac_size); 3606 DMEMIT(";"); 3607 break; 3608 } 3609 } 3610 3611 static void crypt_postsuspend(struct dm_target *ti) 3612 { 3613 struct crypt_config *cc = ti->private; 3614 3615 set_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3616 } 3617 3618 static int crypt_preresume(struct dm_target *ti) 3619 { 3620 struct crypt_config *cc = ti->private; 3621 3622 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { 3623 DMERR("aborting resume - crypt key is not set."); 3624 return -EAGAIN; 3625 } 3626 3627 return 0; 3628 } 3629 3630 static void crypt_resume(struct dm_target *ti) 3631 { 3632 struct crypt_config *cc = ti->private; 3633 3634 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3635 } 3636 3637 /* Message interface 3638 * key set <key> 3639 * key wipe 3640 */ 3641 static int crypt_message(struct dm_target *ti, unsigned int argc, char **argv, 3642 char *result, unsigned int maxlen) 3643 { 3644 struct crypt_config *cc = ti->private; 3645 int key_size, ret = -EINVAL; 3646 3647 if (argc < 2) 3648 goto error; 3649 3650 if (!strcasecmp(argv[0], "key")) { 3651 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { 3652 DMWARN("not suspended during key manipulation."); 3653 return -EINVAL; 3654 } 3655 if (argc == 3 && !strcasecmp(argv[1], "set")) { 3656 /* The key size may not be changed. */ 3657 key_size = get_key_size(&argv[2]); 3658 if (key_size < 0 || cc->key_size != key_size) { 3659 memset(argv[2], '0', strlen(argv[2])); 3660 return -EINVAL; 3661 } 3662 3663 ret = crypt_set_key(cc, argv[2]); 3664 if (ret) 3665 return ret; 3666 if (cc->iv_gen_ops && cc->iv_gen_ops->init) 3667 ret = cc->iv_gen_ops->init(cc); 3668 /* wipe the kernel key payload copy */ 3669 if (cc->key_string) 3670 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3671 return ret; 3672 } 3673 if (argc == 2 && !strcasecmp(argv[1], "wipe")) 3674 return crypt_wipe_key(cc); 3675 } 3676 3677 error: 3678 DMWARN("unrecognised message received."); 3679 return -EINVAL; 3680 } 3681 3682 static int crypt_iterate_devices(struct dm_target *ti, 3683 iterate_devices_callout_fn fn, void *data) 3684 { 3685 struct crypt_config *cc = ti->private; 3686 3687 return fn(ti, cc->dev, cc->start, ti->len, data); 3688 } 3689 3690 static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits) 3691 { 3692 struct crypt_config *cc = ti->private; 3693 3694 /* 3695 * Unfortunate constraint that is required to avoid the potential 3696 * for exceeding underlying device's max_segments limits -- due to 3697 * crypt_alloc_buffer() possibly allocating pages for the encryption 3698 * bio that are not as physically contiguous as the original bio. 3699 */ 3700 limits->max_segment_size = PAGE_SIZE; 3701 3702 limits->logical_block_size = 3703 max_t(unsigned int, limits->logical_block_size, cc->sector_size); 3704 limits->physical_block_size = 3705 max_t(unsigned int, limits->physical_block_size, cc->sector_size); 3706 limits->io_min = max_t(unsigned int, limits->io_min, cc->sector_size); 3707 limits->dma_alignment = limits->logical_block_size - 1; 3708 } 3709 3710 static struct target_type crypt_target = { 3711 .name = "crypt", 3712 .version = {1, 24, 0}, 3713 .module = THIS_MODULE, 3714 .ctr = crypt_ctr, 3715 .dtr = crypt_dtr, 3716 .features = DM_TARGET_ZONED_HM, 3717 .report_zones = crypt_report_zones, 3718 .map = crypt_map, 3719 .status = crypt_status, 3720 .postsuspend = crypt_postsuspend, 3721 .preresume = crypt_preresume, 3722 .resume = crypt_resume, 3723 .message = crypt_message, 3724 .iterate_devices = crypt_iterate_devices, 3725 .io_hints = crypt_io_hints, 3726 }; 3727 module_dm(crypt); 3728 3729 MODULE_AUTHOR("Jana Saout <jana@saout.de>"); 3730 MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); 3731 MODULE_LICENSE("GPL"); 3732