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 bio *bio_out; 57 struct bvec_iter iter_in; 58 struct bvec_iter iter_out; 59 u64 cc_sector; 60 atomic_t cc_pending; 61 union { 62 struct skcipher_request *req; 63 struct aead_request *req_aead; 64 } r; 65 66 }; 67 68 /* 69 * per bio private data 70 */ 71 struct dm_crypt_io { 72 struct crypt_config *cc; 73 struct bio *base_bio; 74 u8 *integrity_metadata; 75 bool integrity_metadata_from_pool:1; 76 bool in_tasklet:1; 77 78 struct work_struct work; 79 struct tasklet_struct tasklet; 80 81 struct convert_context ctx; 82 83 atomic_t io_pending; 84 blk_status_t error; 85 sector_t sector; 86 87 struct rb_node rb_node; 88 } CRYPTO_MINALIGN_ATTR; 89 90 struct dm_crypt_request { 91 struct convert_context *ctx; 92 struct scatterlist sg_in[4]; 93 struct scatterlist sg_out[4]; 94 u64 iv_sector; 95 }; 96 97 struct crypt_config; 98 99 struct crypt_iv_operations { 100 int (*ctr)(struct crypt_config *cc, struct dm_target *ti, 101 const char *opts); 102 void (*dtr)(struct crypt_config *cc); 103 int (*init)(struct crypt_config *cc); 104 int (*wipe)(struct crypt_config *cc); 105 int (*generator)(struct crypt_config *cc, u8 *iv, 106 struct dm_crypt_request *dmreq); 107 int (*post)(struct crypt_config *cc, u8 *iv, 108 struct dm_crypt_request *dmreq); 109 }; 110 111 struct iv_benbi_private { 112 int shift; 113 }; 114 115 #define LMK_SEED_SIZE 64 /* hash + 0 */ 116 struct iv_lmk_private { 117 struct crypto_shash *hash_tfm; 118 u8 *seed; 119 }; 120 121 #define TCW_WHITENING_SIZE 16 122 struct iv_tcw_private { 123 struct crypto_shash *crc32_tfm; 124 u8 *iv_seed; 125 u8 *whitening; 126 }; 127 128 #define ELEPHANT_MAX_KEY_SIZE 32 129 struct iv_elephant_private { 130 struct crypto_skcipher *tfm; 131 }; 132 133 /* 134 * Crypt: maps a linear range of a block device 135 * and encrypts / decrypts at the same time. 136 */ 137 enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID, 138 DM_CRYPT_SAME_CPU, DM_CRYPT_NO_OFFLOAD, 139 DM_CRYPT_NO_READ_WORKQUEUE, DM_CRYPT_NO_WRITE_WORKQUEUE, 140 DM_CRYPT_WRITE_INLINE }; 141 142 enum cipher_flags { 143 CRYPT_MODE_INTEGRITY_AEAD, /* Use authenticated mode for cipher */ 144 CRYPT_IV_LARGE_SECTORS, /* Calculate IV from sector_size, not 512B sectors */ 145 CRYPT_ENCRYPT_PREPROCESS, /* Must preprocess data for encryption (elephant) */ 146 }; 147 148 /* 149 * The fields in here must be read only after initialization. 150 */ 151 struct crypt_config { 152 struct dm_dev *dev; 153 sector_t start; 154 155 struct percpu_counter n_allocated_pages; 156 157 struct workqueue_struct *io_queue; 158 struct workqueue_struct *crypt_queue; 159 160 spinlock_t write_thread_lock; 161 struct task_struct *write_thread; 162 struct rb_root write_tree; 163 164 char *cipher_string; 165 char *cipher_auth; 166 char *key_string; 167 168 const struct crypt_iv_operations *iv_gen_ops; 169 union { 170 struct iv_benbi_private benbi; 171 struct iv_lmk_private lmk; 172 struct iv_tcw_private tcw; 173 struct iv_elephant_private elephant; 174 } iv_gen_private; 175 u64 iv_offset; 176 unsigned int iv_size; 177 unsigned short sector_size; 178 unsigned char sector_shift; 179 180 union { 181 struct crypto_skcipher **tfms; 182 struct crypto_aead **tfms_aead; 183 } cipher_tfm; 184 unsigned int tfms_count; 185 unsigned long cipher_flags; 186 187 /* 188 * Layout of each crypto request: 189 * 190 * struct skcipher_request 191 * context 192 * padding 193 * struct dm_crypt_request 194 * padding 195 * IV 196 * 197 * The padding is added so that dm_crypt_request and the IV are 198 * correctly aligned. 199 */ 200 unsigned int dmreq_start; 201 202 unsigned int per_bio_data_size; 203 204 unsigned long flags; 205 unsigned int key_size; 206 unsigned int key_parts; /* independent parts in key buffer */ 207 unsigned int key_extra_size; /* additional keys length */ 208 unsigned int key_mac_size; /* MAC key size for authenc(...) */ 209 210 unsigned int integrity_tag_size; 211 unsigned int integrity_iv_size; 212 unsigned int on_disk_tag_size; 213 214 /* 215 * pool for per bio private data, crypto requests, 216 * encryption requeusts/buffer pages and integrity tags 217 */ 218 unsigned int tag_pool_max_sectors; 219 mempool_t tag_pool; 220 mempool_t req_pool; 221 mempool_t page_pool; 222 223 struct bio_set bs; 224 struct mutex bio_alloc_lock; 225 226 u8 *authenc_key; /* space for keys in authenc() format (if used) */ 227 u8 key[]; 228 }; 229 230 #define MIN_IOS 64 231 #define MAX_TAG_SIZE 480 232 #define POOL_ENTRY_SIZE 512 233 234 static DEFINE_SPINLOCK(dm_crypt_clients_lock); 235 static unsigned int dm_crypt_clients_n; 236 static volatile unsigned long dm_crypt_pages_per_client; 237 #define DM_CRYPT_MEMORY_PERCENT 2 238 #define DM_CRYPT_MIN_PAGES_PER_CLIENT (BIO_MAX_VECS * 16) 239 240 static void crypt_endio(struct bio *clone); 241 static void kcryptd_queue_crypt(struct dm_crypt_io *io); 242 static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 243 struct scatterlist *sg); 244 245 static bool crypt_integrity_aead(struct crypt_config *cc); 246 247 /* 248 * Use this to access cipher attributes that are independent of the key. 249 */ 250 static struct crypto_skcipher *any_tfm(struct crypt_config *cc) 251 { 252 return cc->cipher_tfm.tfms[0]; 253 } 254 255 static struct crypto_aead *any_tfm_aead(struct crypt_config *cc) 256 { 257 return cc->cipher_tfm.tfms_aead[0]; 258 } 259 260 /* 261 * Different IV generation algorithms: 262 * 263 * plain: the initial vector is the 32-bit little-endian version of the sector 264 * number, padded with zeros if necessary. 265 * 266 * plain64: the initial vector is the 64-bit little-endian version of the sector 267 * number, padded with zeros if necessary. 268 * 269 * plain64be: the initial vector is the 64-bit big-endian version of the sector 270 * number, padded with zeros if necessary. 271 * 272 * essiv: "encrypted sector|salt initial vector", the sector number is 273 * encrypted with the bulk cipher using a salt as key. The salt 274 * should be derived from the bulk cipher's key via hashing. 275 * 276 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 277 * (needed for LRW-32-AES and possible other narrow block modes) 278 * 279 * null: the initial vector is always zero. Provides compatibility with 280 * obsolete loop_fish2 devices. Do not use for new devices. 281 * 282 * lmk: Compatible implementation of the block chaining mode used 283 * by the Loop-AES block device encryption system 284 * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/ 285 * It operates on full 512 byte sectors and uses CBC 286 * with an IV derived from the sector number, the data and 287 * optionally extra IV seed. 288 * This means that after decryption the first block 289 * of sector must be tweaked according to decrypted data. 290 * Loop-AES can use three encryption schemes: 291 * version 1: is plain aes-cbc mode 292 * version 2: uses 64 multikey scheme with lmk IV generator 293 * version 3: the same as version 2 with additional IV seed 294 * (it uses 65 keys, last key is used as IV seed) 295 * 296 * tcw: Compatible implementation of the block chaining mode used 297 * by the TrueCrypt device encryption system (prior to version 4.1). 298 * For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat 299 * It operates on full 512 byte sectors and uses CBC 300 * with an IV derived from initial key and the sector number. 301 * In addition, whitening value is applied on every sector, whitening 302 * is calculated from initial key, sector number and mixed using CRC32. 303 * Note that this encryption scheme is vulnerable to watermarking attacks 304 * and should be used for old compatible containers access only. 305 * 306 * eboiv: Encrypted byte-offset IV (used in Bitlocker in CBC mode) 307 * The IV is encrypted little-endian byte-offset (with the same key 308 * and cipher as the volume). 309 * 310 * elephant: The extended version of eboiv with additional Elephant diffuser 311 * used with Bitlocker CBC mode. 312 * This mode was used in older Windows systems 313 * https://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf 314 */ 315 316 static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, 317 struct dm_crypt_request *dmreq) 318 { 319 memset(iv, 0, cc->iv_size); 320 *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff); 321 322 return 0; 323 } 324 325 static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv, 326 struct dm_crypt_request *dmreq) 327 { 328 memset(iv, 0, cc->iv_size); 329 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 330 331 return 0; 332 } 333 334 static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv, 335 struct dm_crypt_request *dmreq) 336 { 337 memset(iv, 0, cc->iv_size); 338 /* iv_size is at least of size u64; usually it is 16 bytes */ 339 *(__be64 *)&iv[cc->iv_size - sizeof(u64)] = cpu_to_be64(dmreq->iv_sector); 340 341 return 0; 342 } 343 344 static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, 345 struct dm_crypt_request *dmreq) 346 { 347 /* 348 * ESSIV encryption of the IV is now handled by the crypto API, 349 * so just pass the plain sector number here. 350 */ 351 memset(iv, 0, cc->iv_size); 352 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 353 354 return 0; 355 } 356 357 static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, 358 const char *opts) 359 { 360 unsigned int bs; 361 int log; 362 363 if (crypt_integrity_aead(cc)) 364 bs = crypto_aead_blocksize(any_tfm_aead(cc)); 365 else 366 bs = crypto_skcipher_blocksize(any_tfm(cc)); 367 log = ilog2(bs); 368 369 /* 370 * We need to calculate how far we must shift the sector count 371 * to get the cipher block count, we use this shift in _gen. 372 */ 373 if (1 << log != bs) { 374 ti->error = "cypher blocksize is not a power of 2"; 375 return -EINVAL; 376 } 377 378 if (log > 9) { 379 ti->error = "cypher blocksize is > 512"; 380 return -EINVAL; 381 } 382 383 cc->iv_gen_private.benbi.shift = 9 - log; 384 385 return 0; 386 } 387 388 static void crypt_iv_benbi_dtr(struct crypt_config *cc) 389 { 390 } 391 392 static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, 393 struct dm_crypt_request *dmreq) 394 { 395 __be64 val; 396 397 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ 398 399 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1); 400 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); 401 402 return 0; 403 } 404 405 static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, 406 struct dm_crypt_request *dmreq) 407 { 408 memset(iv, 0, cc->iv_size); 409 410 return 0; 411 } 412 413 static void crypt_iv_lmk_dtr(struct crypt_config *cc) 414 { 415 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 416 417 if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm)) 418 crypto_free_shash(lmk->hash_tfm); 419 lmk->hash_tfm = NULL; 420 421 kfree_sensitive(lmk->seed); 422 lmk->seed = NULL; 423 } 424 425 static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti, 426 const char *opts) 427 { 428 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 429 430 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 431 ti->error = "Unsupported sector size for LMK"; 432 return -EINVAL; 433 } 434 435 lmk->hash_tfm = crypto_alloc_shash("md5", 0, 436 CRYPTO_ALG_ALLOCATES_MEMORY); 437 if (IS_ERR(lmk->hash_tfm)) { 438 ti->error = "Error initializing LMK hash"; 439 return PTR_ERR(lmk->hash_tfm); 440 } 441 442 /* No seed in LMK version 2 */ 443 if (cc->key_parts == cc->tfms_count) { 444 lmk->seed = NULL; 445 return 0; 446 } 447 448 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL); 449 if (!lmk->seed) { 450 crypt_iv_lmk_dtr(cc); 451 ti->error = "Error kmallocing seed storage in LMK"; 452 return -ENOMEM; 453 } 454 455 return 0; 456 } 457 458 static int crypt_iv_lmk_init(struct crypt_config *cc) 459 { 460 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 461 int subkey_size = cc->key_size / cc->key_parts; 462 463 /* LMK seed is on the position of LMK_KEYS + 1 key */ 464 if (lmk->seed) 465 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size), 466 crypto_shash_digestsize(lmk->hash_tfm)); 467 468 return 0; 469 } 470 471 static int crypt_iv_lmk_wipe(struct crypt_config *cc) 472 { 473 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 474 475 if (lmk->seed) 476 memset(lmk->seed, 0, LMK_SEED_SIZE); 477 478 return 0; 479 } 480 481 static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv, 482 struct dm_crypt_request *dmreq, 483 u8 *data) 484 { 485 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 486 SHASH_DESC_ON_STACK(desc, lmk->hash_tfm); 487 struct md5_state md5state; 488 __le32 buf[4]; 489 int i, r; 490 491 desc->tfm = lmk->hash_tfm; 492 493 r = crypto_shash_init(desc); 494 if (r) 495 return r; 496 497 if (lmk->seed) { 498 r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE); 499 if (r) 500 return r; 501 } 502 503 /* Sector is always 512B, block size 16, add data of blocks 1-31 */ 504 r = crypto_shash_update(desc, data + 16, 16 * 31); 505 if (r) 506 return r; 507 508 /* Sector is cropped to 56 bits here */ 509 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF); 510 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000); 511 buf[2] = cpu_to_le32(4024); 512 buf[3] = 0; 513 r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf)); 514 if (r) 515 return r; 516 517 /* No MD5 padding here */ 518 r = crypto_shash_export(desc, &md5state); 519 if (r) 520 return r; 521 522 for (i = 0; i < MD5_HASH_WORDS; i++) 523 __cpu_to_le32s(&md5state.hash[i]); 524 memcpy(iv, &md5state.hash, cc->iv_size); 525 526 return 0; 527 } 528 529 static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv, 530 struct dm_crypt_request *dmreq) 531 { 532 struct scatterlist *sg; 533 u8 *src; 534 int r = 0; 535 536 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 537 sg = crypt_get_sg_data(cc, dmreq->sg_in); 538 src = kmap_local_page(sg_page(sg)); 539 r = crypt_iv_lmk_one(cc, iv, dmreq, src + sg->offset); 540 kunmap_local(src); 541 } else 542 memset(iv, 0, cc->iv_size); 543 544 return r; 545 } 546 547 static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv, 548 struct dm_crypt_request *dmreq) 549 { 550 struct scatterlist *sg; 551 u8 *dst; 552 int r; 553 554 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) 555 return 0; 556 557 sg = crypt_get_sg_data(cc, dmreq->sg_out); 558 dst = kmap_local_page(sg_page(sg)); 559 r = crypt_iv_lmk_one(cc, iv, dmreq, dst + sg->offset); 560 561 /* Tweak the first block of plaintext sector */ 562 if (!r) 563 crypto_xor(dst + sg->offset, iv, cc->iv_size); 564 565 kunmap_local(dst); 566 return r; 567 } 568 569 static void crypt_iv_tcw_dtr(struct crypt_config *cc) 570 { 571 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 572 573 kfree_sensitive(tcw->iv_seed); 574 tcw->iv_seed = NULL; 575 kfree_sensitive(tcw->whitening); 576 tcw->whitening = NULL; 577 578 if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm)) 579 crypto_free_shash(tcw->crc32_tfm); 580 tcw->crc32_tfm = NULL; 581 } 582 583 static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti, 584 const char *opts) 585 { 586 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 587 588 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 589 ti->error = "Unsupported sector size for TCW"; 590 return -EINVAL; 591 } 592 593 if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) { 594 ti->error = "Wrong key size for TCW"; 595 return -EINVAL; 596 } 597 598 tcw->crc32_tfm = crypto_alloc_shash("crc32", 0, 599 CRYPTO_ALG_ALLOCATES_MEMORY); 600 if (IS_ERR(tcw->crc32_tfm)) { 601 ti->error = "Error initializing CRC32 in TCW"; 602 return PTR_ERR(tcw->crc32_tfm); 603 } 604 605 tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL); 606 tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL); 607 if (!tcw->iv_seed || !tcw->whitening) { 608 crypt_iv_tcw_dtr(cc); 609 ti->error = "Error allocating seed storage in TCW"; 610 return -ENOMEM; 611 } 612 613 return 0; 614 } 615 616 static int crypt_iv_tcw_init(struct crypt_config *cc) 617 { 618 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 619 int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE; 620 621 memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size); 622 memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size], 623 TCW_WHITENING_SIZE); 624 625 return 0; 626 } 627 628 static int crypt_iv_tcw_wipe(struct crypt_config *cc) 629 { 630 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 631 632 memset(tcw->iv_seed, 0, cc->iv_size); 633 memset(tcw->whitening, 0, TCW_WHITENING_SIZE); 634 635 return 0; 636 } 637 638 static int crypt_iv_tcw_whitening(struct crypt_config *cc, 639 struct dm_crypt_request *dmreq, 640 u8 *data) 641 { 642 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 643 __le64 sector = cpu_to_le64(dmreq->iv_sector); 644 u8 buf[TCW_WHITENING_SIZE]; 645 SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm); 646 int i, r; 647 648 /* xor whitening with sector number */ 649 crypto_xor_cpy(buf, tcw->whitening, (u8 *)§or, 8); 650 crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)§or, 8); 651 652 /* calculate crc32 for every 32bit part and xor it */ 653 desc->tfm = tcw->crc32_tfm; 654 for (i = 0; i < 4; i++) { 655 r = crypto_shash_init(desc); 656 if (r) 657 goto out; 658 r = crypto_shash_update(desc, &buf[i * 4], 4); 659 if (r) 660 goto out; 661 r = crypto_shash_final(desc, &buf[i * 4]); 662 if (r) 663 goto out; 664 } 665 crypto_xor(&buf[0], &buf[12], 4); 666 crypto_xor(&buf[4], &buf[8], 4); 667 668 /* apply whitening (8 bytes) to whole sector */ 669 for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++) 670 crypto_xor(data + i * 8, buf, 8); 671 out: 672 memzero_explicit(buf, sizeof(buf)); 673 return r; 674 } 675 676 static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv, 677 struct dm_crypt_request *dmreq) 678 { 679 struct scatterlist *sg; 680 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 681 __le64 sector = cpu_to_le64(dmreq->iv_sector); 682 u8 *src; 683 int r = 0; 684 685 /* Remove whitening from ciphertext */ 686 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 687 sg = crypt_get_sg_data(cc, dmreq->sg_in); 688 src = kmap_local_page(sg_page(sg)); 689 r = crypt_iv_tcw_whitening(cc, dmreq, src + sg->offset); 690 kunmap_local(src); 691 } 692 693 /* Calculate IV */ 694 crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)§or, 8); 695 if (cc->iv_size > 8) 696 crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)§or, 697 cc->iv_size - 8); 698 699 return r; 700 } 701 702 static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv, 703 struct dm_crypt_request *dmreq) 704 { 705 struct scatterlist *sg; 706 u8 *dst; 707 int r; 708 709 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 710 return 0; 711 712 /* Apply whitening on ciphertext */ 713 sg = crypt_get_sg_data(cc, dmreq->sg_out); 714 dst = kmap_local_page(sg_page(sg)); 715 r = crypt_iv_tcw_whitening(cc, dmreq, dst + sg->offset); 716 kunmap_local(dst); 717 718 return r; 719 } 720 721 static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv, 722 struct dm_crypt_request *dmreq) 723 { 724 /* Used only for writes, there must be an additional space to store IV */ 725 get_random_bytes(iv, cc->iv_size); 726 return 0; 727 } 728 729 static int crypt_iv_eboiv_ctr(struct crypt_config *cc, struct dm_target *ti, 730 const char *opts) 731 { 732 if (crypt_integrity_aead(cc)) { 733 ti->error = "AEAD transforms not supported for EBOIV"; 734 return -EINVAL; 735 } 736 737 if (crypto_skcipher_blocksize(any_tfm(cc)) != cc->iv_size) { 738 ti->error = "Block size of EBOIV cipher does not match IV size of block cipher"; 739 return -EINVAL; 740 } 741 742 return 0; 743 } 744 745 static int crypt_iv_eboiv_gen(struct crypt_config *cc, u8 *iv, 746 struct dm_crypt_request *dmreq) 747 { 748 struct crypto_skcipher *tfm = any_tfm(cc); 749 struct skcipher_request *req; 750 struct scatterlist src, dst; 751 DECLARE_CRYPTO_WAIT(wait); 752 unsigned int reqsize; 753 int err; 754 u8 *buf; 755 756 reqsize = sizeof(*req) + crypto_skcipher_reqsize(tfm); 757 reqsize = ALIGN(reqsize, __alignof__(__le64)); 758 759 req = kmalloc(reqsize + cc->iv_size, GFP_NOIO); 760 if (!req) 761 return -ENOMEM; 762 763 skcipher_request_set_tfm(req, tfm); 764 765 buf = (u8 *)req + reqsize; 766 memset(buf, 0, cc->iv_size); 767 *(__le64 *)buf = cpu_to_le64(dmreq->iv_sector * cc->sector_size); 768 769 sg_init_one(&src, page_address(ZERO_PAGE(0)), cc->iv_size); 770 sg_init_one(&dst, iv, cc->iv_size); 771 skcipher_request_set_crypt(req, &src, &dst, cc->iv_size, buf); 772 skcipher_request_set_callback(req, 0, crypto_req_done, &wait); 773 err = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 774 kfree_sensitive(req); 775 776 return err; 777 } 778 779 static void crypt_iv_elephant_dtr(struct crypt_config *cc) 780 { 781 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 782 783 crypto_free_skcipher(elephant->tfm); 784 elephant->tfm = NULL; 785 } 786 787 static int crypt_iv_elephant_ctr(struct crypt_config *cc, struct dm_target *ti, 788 const char *opts) 789 { 790 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 791 int r; 792 793 elephant->tfm = crypto_alloc_skcipher("ecb(aes)", 0, 794 CRYPTO_ALG_ALLOCATES_MEMORY); 795 if (IS_ERR(elephant->tfm)) { 796 r = PTR_ERR(elephant->tfm); 797 elephant->tfm = NULL; 798 return r; 799 } 800 801 r = crypt_iv_eboiv_ctr(cc, ti, NULL); 802 if (r) 803 crypt_iv_elephant_dtr(cc); 804 return r; 805 } 806 807 static void diffuser_disk_to_cpu(u32 *d, size_t n) 808 { 809 #ifndef __LITTLE_ENDIAN 810 int i; 811 812 for (i = 0; i < n; i++) 813 d[i] = le32_to_cpu((__le32)d[i]); 814 #endif 815 } 816 817 static void diffuser_cpu_to_disk(__le32 *d, size_t n) 818 { 819 #ifndef __LITTLE_ENDIAN 820 int i; 821 822 for (i = 0; i < n; i++) 823 d[i] = cpu_to_le32((u32)d[i]); 824 #endif 825 } 826 827 static void diffuser_a_decrypt(u32 *d, size_t n) 828 { 829 int i, i1, i2, i3; 830 831 for (i = 0; i < 5; i++) { 832 i1 = 0; 833 i2 = n - 2; 834 i3 = n - 5; 835 836 while (i1 < (n - 1)) { 837 d[i1] += d[i2] ^ (d[i3] << 9 | d[i3] >> 23); 838 i1++; i2++; i3++; 839 840 if (i3 >= n) 841 i3 -= n; 842 843 d[i1] += d[i2] ^ d[i3]; 844 i1++; i2++; i3++; 845 846 if (i2 >= n) 847 i2 -= n; 848 849 d[i1] += d[i2] ^ (d[i3] << 13 | d[i3] >> 19); 850 i1++; i2++; i3++; 851 852 d[i1] += d[i2] ^ d[i3]; 853 i1++; i2++; i3++; 854 } 855 } 856 } 857 858 static void diffuser_a_encrypt(u32 *d, size_t n) 859 { 860 int i, i1, i2, i3; 861 862 for (i = 0; i < 5; i++) { 863 i1 = n - 1; 864 i2 = n - 2 - 1; 865 i3 = n - 5 - 1; 866 867 while (i1 > 0) { 868 d[i1] -= d[i2] ^ d[i3]; 869 i1--; i2--; i3--; 870 871 d[i1] -= d[i2] ^ (d[i3] << 13 | d[i3] >> 19); 872 i1--; i2--; i3--; 873 874 if (i2 < 0) 875 i2 += n; 876 877 d[i1] -= d[i2] ^ d[i3]; 878 i1--; i2--; i3--; 879 880 if (i3 < 0) 881 i3 += n; 882 883 d[i1] -= d[i2] ^ (d[i3] << 9 | d[i3] >> 23); 884 i1--; i2--; i3--; 885 } 886 } 887 } 888 889 static void diffuser_b_decrypt(u32 *d, size_t n) 890 { 891 int i, i1, i2, i3; 892 893 for (i = 0; i < 3; i++) { 894 i1 = 0; 895 i2 = 2; 896 i3 = 5; 897 898 while (i1 < (n - 1)) { 899 d[i1] += d[i2] ^ d[i3]; 900 i1++; i2++; i3++; 901 902 d[i1] += d[i2] ^ (d[i3] << 10 | d[i3] >> 22); 903 i1++; i2++; i3++; 904 905 if (i2 >= n) 906 i2 -= n; 907 908 d[i1] += d[i2] ^ d[i3]; 909 i1++; i2++; i3++; 910 911 if (i3 >= n) 912 i3 -= n; 913 914 d[i1] += d[i2] ^ (d[i3] << 25 | d[i3] >> 7); 915 i1++; i2++; i3++; 916 } 917 } 918 } 919 920 static void diffuser_b_encrypt(u32 *d, size_t n) 921 { 922 int i, i1, i2, i3; 923 924 for (i = 0; i < 3; i++) { 925 i1 = n - 1; 926 i2 = 2 - 1; 927 i3 = 5 - 1; 928 929 while (i1 > 0) { 930 d[i1] -= d[i2] ^ (d[i3] << 25 | d[i3] >> 7); 931 i1--; i2--; i3--; 932 933 if (i3 < 0) 934 i3 += n; 935 936 d[i1] -= d[i2] ^ d[i3]; 937 i1--; i2--; i3--; 938 939 if (i2 < 0) 940 i2 += n; 941 942 d[i1] -= d[i2] ^ (d[i3] << 10 | d[i3] >> 22); 943 i1--; i2--; i3--; 944 945 d[i1] -= d[i2] ^ d[i3]; 946 i1--; i2--; i3--; 947 } 948 } 949 } 950 951 static int crypt_iv_elephant(struct crypt_config *cc, struct dm_crypt_request *dmreq) 952 { 953 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 954 u8 *es, *ks, *data, *data2, *data_offset; 955 struct skcipher_request *req; 956 struct scatterlist *sg, *sg2, src, dst; 957 DECLARE_CRYPTO_WAIT(wait); 958 int i, r; 959 960 req = skcipher_request_alloc(elephant->tfm, GFP_NOIO); 961 es = kzalloc(16, GFP_NOIO); /* Key for AES */ 962 ks = kzalloc(32, GFP_NOIO); /* Elephant sector key */ 963 964 if (!req || !es || !ks) { 965 r = -ENOMEM; 966 goto out; 967 } 968 969 *(__le64 *)es = cpu_to_le64(dmreq->iv_sector * cc->sector_size); 970 971 /* E(Ks, e(s)) */ 972 sg_init_one(&src, es, 16); 973 sg_init_one(&dst, ks, 16); 974 skcipher_request_set_crypt(req, &src, &dst, 16, NULL); 975 skcipher_request_set_callback(req, 0, crypto_req_done, &wait); 976 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 977 if (r) 978 goto out; 979 980 /* E(Ks, e'(s)) */ 981 es[15] = 0x80; 982 sg_init_one(&dst, &ks[16], 16); 983 r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 984 if (r) 985 goto out; 986 987 sg = crypt_get_sg_data(cc, dmreq->sg_out); 988 data = kmap_local_page(sg_page(sg)); 989 data_offset = data + sg->offset; 990 991 /* Cannot modify original bio, copy to sg_out and apply Elephant to it */ 992 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 993 sg2 = crypt_get_sg_data(cc, dmreq->sg_in); 994 data2 = kmap_local_page(sg_page(sg2)); 995 memcpy(data_offset, data2 + sg2->offset, cc->sector_size); 996 kunmap_local(data2); 997 } 998 999 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 1000 diffuser_disk_to_cpu((u32 *)data_offset, cc->sector_size / sizeof(u32)); 1001 diffuser_b_decrypt((u32 *)data_offset, cc->sector_size / sizeof(u32)); 1002 diffuser_a_decrypt((u32 *)data_offset, cc->sector_size / sizeof(u32)); 1003 diffuser_cpu_to_disk((__le32 *)data_offset, cc->sector_size / sizeof(u32)); 1004 } 1005 1006 for (i = 0; i < (cc->sector_size / 32); i++) 1007 crypto_xor(data_offset + i * 32, ks, 32); 1008 1009 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 1010 diffuser_disk_to_cpu((u32 *)data_offset, cc->sector_size / sizeof(u32)); 1011 diffuser_a_encrypt((u32 *)data_offset, cc->sector_size / sizeof(u32)); 1012 diffuser_b_encrypt((u32 *)data_offset, cc->sector_size / sizeof(u32)); 1013 diffuser_cpu_to_disk((__le32 *)data_offset, cc->sector_size / sizeof(u32)); 1014 } 1015 1016 kunmap_local(data); 1017 out: 1018 kfree_sensitive(ks); 1019 kfree_sensitive(es); 1020 skcipher_request_free(req); 1021 return r; 1022 } 1023 1024 static int crypt_iv_elephant_gen(struct crypt_config *cc, u8 *iv, 1025 struct dm_crypt_request *dmreq) 1026 { 1027 int r; 1028 1029 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 1030 r = crypt_iv_elephant(cc, dmreq); 1031 if (r) 1032 return r; 1033 } 1034 1035 return crypt_iv_eboiv_gen(cc, iv, dmreq); 1036 } 1037 1038 static int crypt_iv_elephant_post(struct crypt_config *cc, u8 *iv, 1039 struct dm_crypt_request *dmreq) 1040 { 1041 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 1042 return crypt_iv_elephant(cc, dmreq); 1043 1044 return 0; 1045 } 1046 1047 static int crypt_iv_elephant_init(struct crypt_config *cc) 1048 { 1049 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 1050 int key_offset = cc->key_size - cc->key_extra_size; 1051 1052 return crypto_skcipher_setkey(elephant->tfm, &cc->key[key_offset], cc->key_extra_size); 1053 } 1054 1055 static int crypt_iv_elephant_wipe(struct crypt_config *cc) 1056 { 1057 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 1058 u8 key[ELEPHANT_MAX_KEY_SIZE]; 1059 1060 memset(key, 0, cc->key_extra_size); 1061 return crypto_skcipher_setkey(elephant->tfm, key, cc->key_extra_size); 1062 } 1063 1064 static const struct crypt_iv_operations crypt_iv_plain_ops = { 1065 .generator = crypt_iv_plain_gen 1066 }; 1067 1068 static const struct crypt_iv_operations crypt_iv_plain64_ops = { 1069 .generator = crypt_iv_plain64_gen 1070 }; 1071 1072 static const struct crypt_iv_operations crypt_iv_plain64be_ops = { 1073 .generator = crypt_iv_plain64be_gen 1074 }; 1075 1076 static const struct crypt_iv_operations crypt_iv_essiv_ops = { 1077 .generator = crypt_iv_essiv_gen 1078 }; 1079 1080 static const struct crypt_iv_operations crypt_iv_benbi_ops = { 1081 .ctr = crypt_iv_benbi_ctr, 1082 .dtr = crypt_iv_benbi_dtr, 1083 .generator = crypt_iv_benbi_gen 1084 }; 1085 1086 static const struct crypt_iv_operations crypt_iv_null_ops = { 1087 .generator = crypt_iv_null_gen 1088 }; 1089 1090 static const struct crypt_iv_operations crypt_iv_lmk_ops = { 1091 .ctr = crypt_iv_lmk_ctr, 1092 .dtr = crypt_iv_lmk_dtr, 1093 .init = crypt_iv_lmk_init, 1094 .wipe = crypt_iv_lmk_wipe, 1095 .generator = crypt_iv_lmk_gen, 1096 .post = crypt_iv_lmk_post 1097 }; 1098 1099 static const struct crypt_iv_operations crypt_iv_tcw_ops = { 1100 .ctr = crypt_iv_tcw_ctr, 1101 .dtr = crypt_iv_tcw_dtr, 1102 .init = crypt_iv_tcw_init, 1103 .wipe = crypt_iv_tcw_wipe, 1104 .generator = crypt_iv_tcw_gen, 1105 .post = crypt_iv_tcw_post 1106 }; 1107 1108 static const struct crypt_iv_operations crypt_iv_random_ops = { 1109 .generator = crypt_iv_random_gen 1110 }; 1111 1112 static const struct crypt_iv_operations crypt_iv_eboiv_ops = { 1113 .ctr = crypt_iv_eboiv_ctr, 1114 .generator = crypt_iv_eboiv_gen 1115 }; 1116 1117 static const struct crypt_iv_operations crypt_iv_elephant_ops = { 1118 .ctr = crypt_iv_elephant_ctr, 1119 .dtr = crypt_iv_elephant_dtr, 1120 .init = crypt_iv_elephant_init, 1121 .wipe = crypt_iv_elephant_wipe, 1122 .generator = crypt_iv_elephant_gen, 1123 .post = crypt_iv_elephant_post 1124 }; 1125 1126 /* 1127 * Integrity extensions 1128 */ 1129 static bool crypt_integrity_aead(struct crypt_config *cc) 1130 { 1131 return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 1132 } 1133 1134 static bool crypt_integrity_hmac(struct crypt_config *cc) 1135 { 1136 return crypt_integrity_aead(cc) && cc->key_mac_size; 1137 } 1138 1139 /* Get sg containing data */ 1140 static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 1141 struct scatterlist *sg) 1142 { 1143 if (unlikely(crypt_integrity_aead(cc))) 1144 return &sg[2]; 1145 1146 return sg; 1147 } 1148 1149 static int dm_crypt_integrity_io_alloc(struct dm_crypt_io *io, struct bio *bio) 1150 { 1151 struct bio_integrity_payload *bip; 1152 unsigned int tag_len; 1153 int ret; 1154 1155 if (!bio_sectors(bio) || !io->cc->on_disk_tag_size) 1156 return 0; 1157 1158 bip = bio_integrity_alloc(bio, GFP_NOIO, 1); 1159 if (IS_ERR(bip)) 1160 return PTR_ERR(bip); 1161 1162 tag_len = io->cc->on_disk_tag_size * (bio_sectors(bio) >> io->cc->sector_shift); 1163 1164 bip->bip_iter.bi_sector = io->cc->start + io->sector; 1165 1166 ret = bio_integrity_add_page(bio, virt_to_page(io->integrity_metadata), 1167 tag_len, offset_in_page(io->integrity_metadata)); 1168 if (unlikely(ret != tag_len)) 1169 return -ENOMEM; 1170 1171 return 0; 1172 } 1173 1174 static int crypt_integrity_ctr(struct crypt_config *cc, struct dm_target *ti) 1175 { 1176 #ifdef CONFIG_BLK_DEV_INTEGRITY 1177 struct blk_integrity *bi = blk_get_integrity(cc->dev->bdev->bd_disk); 1178 struct mapped_device *md = dm_table_get_md(ti->table); 1179 1180 /* From now we require underlying device with our integrity profile */ 1181 if (!bi || strcasecmp(bi->profile->name, "DM-DIF-EXT-TAG")) { 1182 ti->error = "Integrity profile not supported."; 1183 return -EINVAL; 1184 } 1185 1186 if (bi->tag_size != cc->on_disk_tag_size || 1187 bi->tuple_size != cc->on_disk_tag_size) { 1188 ti->error = "Integrity profile tag size mismatch."; 1189 return -EINVAL; 1190 } 1191 if (1 << bi->interval_exp != cc->sector_size) { 1192 ti->error = "Integrity profile sector size mismatch."; 1193 return -EINVAL; 1194 } 1195 1196 if (crypt_integrity_aead(cc)) { 1197 cc->integrity_tag_size = cc->on_disk_tag_size - cc->integrity_iv_size; 1198 DMDEBUG("%s: Integrity AEAD, tag size %u, IV size %u.", dm_device_name(md), 1199 cc->integrity_tag_size, cc->integrity_iv_size); 1200 1201 if (crypto_aead_setauthsize(any_tfm_aead(cc), cc->integrity_tag_size)) { 1202 ti->error = "Integrity AEAD auth tag size is not supported."; 1203 return -EINVAL; 1204 } 1205 } else if (cc->integrity_iv_size) 1206 DMDEBUG("%s: Additional per-sector space %u bytes for IV.", dm_device_name(md), 1207 cc->integrity_iv_size); 1208 1209 if ((cc->integrity_tag_size + cc->integrity_iv_size) != bi->tag_size) { 1210 ti->error = "Not enough space for integrity tag in the profile."; 1211 return -EINVAL; 1212 } 1213 1214 return 0; 1215 #else 1216 ti->error = "Integrity profile not supported."; 1217 return -EINVAL; 1218 #endif 1219 } 1220 1221 static void crypt_convert_init(struct crypt_config *cc, 1222 struct convert_context *ctx, 1223 struct bio *bio_out, struct bio *bio_in, 1224 sector_t sector) 1225 { 1226 ctx->bio_in = bio_in; 1227 ctx->bio_out = bio_out; 1228 if (bio_in) 1229 ctx->iter_in = bio_in->bi_iter; 1230 if (bio_out) 1231 ctx->iter_out = bio_out->bi_iter; 1232 ctx->cc_sector = sector + cc->iv_offset; 1233 init_completion(&ctx->restart); 1234 } 1235 1236 static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc, 1237 void *req) 1238 { 1239 return (struct dm_crypt_request *)((char *)req + cc->dmreq_start); 1240 } 1241 1242 static void *req_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq) 1243 { 1244 return (void *)((char *)dmreq - cc->dmreq_start); 1245 } 1246 1247 static u8 *iv_of_dmreq(struct crypt_config *cc, 1248 struct dm_crypt_request *dmreq) 1249 { 1250 if (crypt_integrity_aead(cc)) 1251 return (u8 *)ALIGN((unsigned long)(dmreq + 1), 1252 crypto_aead_alignmask(any_tfm_aead(cc)) + 1); 1253 else 1254 return (u8 *)ALIGN((unsigned long)(dmreq + 1), 1255 crypto_skcipher_alignmask(any_tfm(cc)) + 1); 1256 } 1257 1258 static u8 *org_iv_of_dmreq(struct crypt_config *cc, 1259 struct dm_crypt_request *dmreq) 1260 { 1261 return iv_of_dmreq(cc, dmreq) + cc->iv_size; 1262 } 1263 1264 static __le64 *org_sector_of_dmreq(struct crypt_config *cc, 1265 struct dm_crypt_request *dmreq) 1266 { 1267 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + cc->iv_size; 1268 1269 return (__le64 *) ptr; 1270 } 1271 1272 static unsigned int *org_tag_of_dmreq(struct crypt_config *cc, 1273 struct dm_crypt_request *dmreq) 1274 { 1275 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + 1276 cc->iv_size + sizeof(uint64_t); 1277 1278 return (unsigned int *)ptr; 1279 } 1280 1281 static void *tag_from_dmreq(struct crypt_config *cc, 1282 struct dm_crypt_request *dmreq) 1283 { 1284 struct convert_context *ctx = dmreq->ctx; 1285 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 1286 1287 return &io->integrity_metadata[*org_tag_of_dmreq(cc, dmreq) * 1288 cc->on_disk_tag_size]; 1289 } 1290 1291 static void *iv_tag_from_dmreq(struct crypt_config *cc, 1292 struct dm_crypt_request *dmreq) 1293 { 1294 return tag_from_dmreq(cc, dmreq) + cc->integrity_tag_size; 1295 } 1296 1297 static int crypt_convert_block_aead(struct crypt_config *cc, 1298 struct convert_context *ctx, 1299 struct aead_request *req, 1300 unsigned int tag_offset) 1301 { 1302 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1303 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1304 struct dm_crypt_request *dmreq; 1305 u8 *iv, *org_iv, *tag_iv, *tag; 1306 __le64 *sector; 1307 int r = 0; 1308 1309 BUG_ON(cc->integrity_iv_size && cc->integrity_iv_size != cc->iv_size); 1310 1311 /* Reject unexpected unaligned bio. */ 1312 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1313 return -EIO; 1314 1315 dmreq = dmreq_of_req(cc, req); 1316 dmreq->iv_sector = ctx->cc_sector; 1317 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1318 dmreq->iv_sector >>= cc->sector_shift; 1319 dmreq->ctx = ctx; 1320 1321 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1322 1323 sector = org_sector_of_dmreq(cc, dmreq); 1324 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1325 1326 iv = iv_of_dmreq(cc, dmreq); 1327 org_iv = org_iv_of_dmreq(cc, dmreq); 1328 tag = tag_from_dmreq(cc, dmreq); 1329 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1330 1331 /* AEAD request: 1332 * |----- AAD -------|------ DATA -------|-- AUTH TAG --| 1333 * | (authenticated) | (auth+encryption) | | 1334 * | sector_LE | IV | sector in/out | tag in/out | 1335 */ 1336 sg_init_table(dmreq->sg_in, 4); 1337 sg_set_buf(&dmreq->sg_in[0], sector, sizeof(uint64_t)); 1338 sg_set_buf(&dmreq->sg_in[1], org_iv, cc->iv_size); 1339 sg_set_page(&dmreq->sg_in[2], bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1340 sg_set_buf(&dmreq->sg_in[3], tag, cc->integrity_tag_size); 1341 1342 sg_init_table(dmreq->sg_out, 4); 1343 sg_set_buf(&dmreq->sg_out[0], sector, sizeof(uint64_t)); 1344 sg_set_buf(&dmreq->sg_out[1], org_iv, cc->iv_size); 1345 sg_set_page(&dmreq->sg_out[2], bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1346 sg_set_buf(&dmreq->sg_out[3], tag, cc->integrity_tag_size); 1347 1348 if (cc->iv_gen_ops) { 1349 /* For READs use IV stored in integrity metadata */ 1350 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1351 memcpy(org_iv, tag_iv, cc->iv_size); 1352 } else { 1353 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1354 if (r < 0) 1355 return r; 1356 /* Store generated IV in integrity metadata */ 1357 if (cc->integrity_iv_size) 1358 memcpy(tag_iv, org_iv, cc->iv_size); 1359 } 1360 /* Working copy of IV, to be modified in crypto API */ 1361 memcpy(iv, org_iv, cc->iv_size); 1362 } 1363 1364 aead_request_set_ad(req, sizeof(uint64_t) + cc->iv_size); 1365 if (bio_data_dir(ctx->bio_in) == WRITE) { 1366 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out, 1367 cc->sector_size, iv); 1368 r = crypto_aead_encrypt(req); 1369 if (cc->integrity_tag_size + cc->integrity_iv_size != cc->on_disk_tag_size) 1370 memset(tag + cc->integrity_tag_size + cc->integrity_iv_size, 0, 1371 cc->on_disk_tag_size - (cc->integrity_tag_size + cc->integrity_iv_size)); 1372 } else { 1373 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out, 1374 cc->sector_size + cc->integrity_tag_size, iv); 1375 r = crypto_aead_decrypt(req); 1376 } 1377 1378 if (r == -EBADMSG) { 1379 sector_t s = le64_to_cpu(*sector); 1380 1381 DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu", 1382 ctx->bio_in->bi_bdev, s); 1383 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead", 1384 ctx->bio_in, s, 0); 1385 } 1386 1387 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1388 r = cc->iv_gen_ops->post(cc, org_iv, dmreq); 1389 1390 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1391 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1392 1393 return r; 1394 } 1395 1396 static int crypt_convert_block_skcipher(struct crypt_config *cc, 1397 struct convert_context *ctx, 1398 struct skcipher_request *req, 1399 unsigned int tag_offset) 1400 { 1401 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1402 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1403 struct scatterlist *sg_in, *sg_out; 1404 struct dm_crypt_request *dmreq; 1405 u8 *iv, *org_iv, *tag_iv; 1406 __le64 *sector; 1407 int r = 0; 1408 1409 /* Reject unexpected unaligned bio. */ 1410 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1411 return -EIO; 1412 1413 dmreq = dmreq_of_req(cc, req); 1414 dmreq->iv_sector = ctx->cc_sector; 1415 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1416 dmreq->iv_sector >>= cc->sector_shift; 1417 dmreq->ctx = ctx; 1418 1419 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1420 1421 iv = iv_of_dmreq(cc, dmreq); 1422 org_iv = org_iv_of_dmreq(cc, dmreq); 1423 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1424 1425 sector = org_sector_of_dmreq(cc, dmreq); 1426 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1427 1428 /* For skcipher we use only the first sg item */ 1429 sg_in = &dmreq->sg_in[0]; 1430 sg_out = &dmreq->sg_out[0]; 1431 1432 sg_init_table(sg_in, 1); 1433 sg_set_page(sg_in, bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1434 1435 sg_init_table(sg_out, 1); 1436 sg_set_page(sg_out, bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1437 1438 if (cc->iv_gen_ops) { 1439 /* For READs use IV stored in integrity metadata */ 1440 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1441 memcpy(org_iv, tag_iv, cc->integrity_iv_size); 1442 } else { 1443 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1444 if (r < 0) 1445 return r; 1446 /* Data can be already preprocessed in generator */ 1447 if (test_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags)) 1448 sg_in = sg_out; 1449 /* Store generated IV in integrity metadata */ 1450 if (cc->integrity_iv_size) 1451 memcpy(tag_iv, org_iv, cc->integrity_iv_size); 1452 } 1453 /* Working copy of IV, to be modified in crypto API */ 1454 memcpy(iv, org_iv, cc->iv_size); 1455 } 1456 1457 skcipher_request_set_crypt(req, sg_in, sg_out, cc->sector_size, iv); 1458 1459 if (bio_data_dir(ctx->bio_in) == WRITE) 1460 r = crypto_skcipher_encrypt(req); 1461 else 1462 r = crypto_skcipher_decrypt(req); 1463 1464 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1465 r = cc->iv_gen_ops->post(cc, org_iv, dmreq); 1466 1467 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1468 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1469 1470 return r; 1471 } 1472 1473 static void kcryptd_async_done(void *async_req, int error); 1474 1475 static int crypt_alloc_req_skcipher(struct crypt_config *cc, 1476 struct convert_context *ctx) 1477 { 1478 unsigned int key_index = ctx->cc_sector & (cc->tfms_count - 1); 1479 1480 if (!ctx->r.req) { 1481 ctx->r.req = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1482 if (!ctx->r.req) 1483 return -ENOMEM; 1484 } 1485 1486 skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]); 1487 1488 /* 1489 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1490 * requests if driver request queue is full. 1491 */ 1492 skcipher_request_set_callback(ctx->r.req, 1493 CRYPTO_TFM_REQ_MAY_BACKLOG, 1494 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req)); 1495 1496 return 0; 1497 } 1498 1499 static int crypt_alloc_req_aead(struct crypt_config *cc, 1500 struct convert_context *ctx) 1501 { 1502 if (!ctx->r.req_aead) { 1503 ctx->r.req_aead = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1504 if (!ctx->r.req_aead) 1505 return -ENOMEM; 1506 } 1507 1508 aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]); 1509 1510 /* 1511 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1512 * requests if driver request queue is full. 1513 */ 1514 aead_request_set_callback(ctx->r.req_aead, 1515 CRYPTO_TFM_REQ_MAY_BACKLOG, 1516 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead)); 1517 1518 return 0; 1519 } 1520 1521 static int crypt_alloc_req(struct crypt_config *cc, 1522 struct convert_context *ctx) 1523 { 1524 if (crypt_integrity_aead(cc)) 1525 return crypt_alloc_req_aead(cc, ctx); 1526 else 1527 return crypt_alloc_req_skcipher(cc, ctx); 1528 } 1529 1530 static void crypt_free_req_skcipher(struct crypt_config *cc, 1531 struct skcipher_request *req, struct bio *base_bio) 1532 { 1533 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1534 1535 if ((struct skcipher_request *)(io + 1) != req) 1536 mempool_free(req, &cc->req_pool); 1537 } 1538 1539 static void crypt_free_req_aead(struct crypt_config *cc, 1540 struct aead_request *req, struct bio *base_bio) 1541 { 1542 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1543 1544 if ((struct aead_request *)(io + 1) != req) 1545 mempool_free(req, &cc->req_pool); 1546 } 1547 1548 static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio) 1549 { 1550 if (crypt_integrity_aead(cc)) 1551 crypt_free_req_aead(cc, req, base_bio); 1552 else 1553 crypt_free_req_skcipher(cc, req, base_bio); 1554 } 1555 1556 /* 1557 * Encrypt / decrypt data from one bio to another one (can be the same one) 1558 */ 1559 static blk_status_t crypt_convert(struct crypt_config *cc, 1560 struct convert_context *ctx, bool atomic, bool reset_pending) 1561 { 1562 unsigned int tag_offset = 0; 1563 unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT; 1564 int r; 1565 1566 /* 1567 * if reset_pending is set we are dealing with the bio for the first time, 1568 * else we're continuing to work on the previous bio, so don't mess with 1569 * the cc_pending counter 1570 */ 1571 if (reset_pending) 1572 atomic_set(&ctx->cc_pending, 1); 1573 1574 while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) { 1575 1576 r = crypt_alloc_req(cc, ctx); 1577 if (r) { 1578 complete(&ctx->restart); 1579 return BLK_STS_DEV_RESOURCE; 1580 } 1581 1582 atomic_inc(&ctx->cc_pending); 1583 1584 if (crypt_integrity_aead(cc)) 1585 r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, tag_offset); 1586 else 1587 r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, tag_offset); 1588 1589 switch (r) { 1590 /* 1591 * The request was queued by a crypto driver 1592 * but the driver request queue is full, let's wait. 1593 */ 1594 case -EBUSY: 1595 if (in_interrupt()) { 1596 if (try_wait_for_completion(&ctx->restart)) { 1597 /* 1598 * we don't have to block to wait for completion, 1599 * so proceed 1600 */ 1601 } else { 1602 /* 1603 * we can't wait for completion without blocking 1604 * exit and continue processing in a workqueue 1605 */ 1606 ctx->r.req = NULL; 1607 ctx->cc_sector += sector_step; 1608 tag_offset++; 1609 return BLK_STS_DEV_RESOURCE; 1610 } 1611 } else { 1612 wait_for_completion(&ctx->restart); 1613 } 1614 reinit_completion(&ctx->restart); 1615 fallthrough; 1616 /* 1617 * The request is queued and processed asynchronously, 1618 * completion function kcryptd_async_done() will be called. 1619 */ 1620 case -EINPROGRESS: 1621 ctx->r.req = NULL; 1622 ctx->cc_sector += sector_step; 1623 tag_offset++; 1624 continue; 1625 /* 1626 * The request was already processed (synchronously). 1627 */ 1628 case 0: 1629 atomic_dec(&ctx->cc_pending); 1630 ctx->cc_sector += sector_step; 1631 tag_offset++; 1632 if (!atomic) 1633 cond_resched(); 1634 continue; 1635 /* 1636 * There was a data integrity error. 1637 */ 1638 case -EBADMSG: 1639 atomic_dec(&ctx->cc_pending); 1640 return BLK_STS_PROTECTION; 1641 /* 1642 * There was an error while processing the request. 1643 */ 1644 default: 1645 atomic_dec(&ctx->cc_pending); 1646 return BLK_STS_IOERR; 1647 } 1648 } 1649 1650 return 0; 1651 } 1652 1653 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone); 1654 1655 /* 1656 * Generate a new unfragmented bio with the given size 1657 * This should never violate the device limitations (but only because 1658 * max_segment_size is being constrained to PAGE_SIZE). 1659 * 1660 * This function may be called concurrently. If we allocate from the mempool 1661 * concurrently, there is a possibility of deadlock. For example, if we have 1662 * mempool of 256 pages, two processes, each wanting 256, pages allocate from 1663 * the mempool concurrently, it may deadlock in a situation where both processes 1664 * have allocated 128 pages and the mempool is exhausted. 1665 * 1666 * In order to avoid this scenario we allocate the pages under a mutex. 1667 * 1668 * In order to not degrade performance with excessive locking, we try 1669 * non-blocking allocations without a mutex first but on failure we fallback 1670 * to blocking allocations with a mutex. 1671 * 1672 * In order to reduce allocation overhead, we try to allocate compound pages in 1673 * the first pass. If they are not available, we fall back to the mempool. 1674 */ 1675 static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned int size) 1676 { 1677 struct crypt_config *cc = io->cc; 1678 struct bio *clone; 1679 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; 1680 gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM; 1681 unsigned int remaining_size; 1682 unsigned int order = MAX_ORDER - 1; 1683 1684 retry: 1685 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1686 mutex_lock(&cc->bio_alloc_lock); 1687 1688 clone = bio_alloc_bioset(cc->dev->bdev, nr_iovecs, io->base_bio->bi_opf, 1689 GFP_NOIO, &cc->bs); 1690 clone->bi_private = io; 1691 clone->bi_end_io = crypt_endio; 1692 1693 remaining_size = size; 1694 1695 while (remaining_size) { 1696 struct page *pages; 1697 unsigned size_to_add; 1698 unsigned remaining_order = __fls((remaining_size + PAGE_SIZE - 1) >> PAGE_SHIFT); 1699 order = min(order, remaining_order); 1700 1701 while (order > 0) { 1702 pages = alloc_pages(gfp_mask 1703 | __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN | __GFP_COMP, 1704 order); 1705 if (likely(pages != NULL)) 1706 goto have_pages; 1707 order--; 1708 } 1709 1710 pages = mempool_alloc(&cc->page_pool, gfp_mask); 1711 if (!pages) { 1712 crypt_free_buffer_pages(cc, clone); 1713 bio_put(clone); 1714 gfp_mask |= __GFP_DIRECT_RECLAIM; 1715 order = 0; 1716 goto retry; 1717 } 1718 1719 have_pages: 1720 size_to_add = min((unsigned)PAGE_SIZE << order, remaining_size); 1721 __bio_add_page(clone, pages, size_to_add, 0); 1722 remaining_size -= size_to_add; 1723 } 1724 1725 /* Allocate space for integrity tags */ 1726 if (dm_crypt_integrity_io_alloc(io, clone)) { 1727 crypt_free_buffer_pages(cc, clone); 1728 bio_put(clone); 1729 clone = NULL; 1730 } 1731 1732 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1733 mutex_unlock(&cc->bio_alloc_lock); 1734 1735 return clone; 1736 } 1737 1738 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) 1739 { 1740 struct folio_iter fi; 1741 1742 if (clone->bi_vcnt > 0) { /* bio_for_each_folio_all crashes with an empty bio */ 1743 bio_for_each_folio_all(fi, clone) { 1744 if (folio_test_large(fi.folio)) 1745 folio_put(fi.folio); 1746 else 1747 mempool_free(&fi.folio->page, &cc->page_pool); 1748 } 1749 } 1750 } 1751 1752 static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc, 1753 struct bio *bio, sector_t sector) 1754 { 1755 io->cc = cc; 1756 io->base_bio = bio; 1757 io->sector = sector; 1758 io->error = 0; 1759 io->ctx.r.req = NULL; 1760 io->integrity_metadata = NULL; 1761 io->integrity_metadata_from_pool = false; 1762 io->in_tasklet = false; 1763 atomic_set(&io->io_pending, 0); 1764 } 1765 1766 static void crypt_inc_pending(struct dm_crypt_io *io) 1767 { 1768 atomic_inc(&io->io_pending); 1769 } 1770 1771 static void kcryptd_io_bio_endio(struct work_struct *work) 1772 { 1773 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 1774 1775 bio_endio(io->base_bio); 1776 } 1777 1778 /* 1779 * One of the bios was finished. Check for completion of 1780 * the whole request and correctly clean up the buffer. 1781 */ 1782 static void crypt_dec_pending(struct dm_crypt_io *io) 1783 { 1784 struct crypt_config *cc = io->cc; 1785 struct bio *base_bio = io->base_bio; 1786 blk_status_t error = io->error; 1787 1788 if (!atomic_dec_and_test(&io->io_pending)) 1789 return; 1790 1791 if (io->ctx.r.req) 1792 crypt_free_req(cc, io->ctx.r.req, base_bio); 1793 1794 if (unlikely(io->integrity_metadata_from_pool)) 1795 mempool_free(io->integrity_metadata, &io->cc->tag_pool); 1796 else 1797 kfree(io->integrity_metadata); 1798 1799 base_bio->bi_status = error; 1800 1801 /* 1802 * If we are running this function from our tasklet, 1803 * we can't call bio_endio() here, because it will call 1804 * clone_endio() from dm.c, which in turn will 1805 * free the current struct dm_crypt_io structure with 1806 * our tasklet. In this case we need to delay bio_endio() 1807 * execution to after the tasklet is done and dequeued. 1808 */ 1809 if (io->in_tasklet) { 1810 INIT_WORK(&io->work, kcryptd_io_bio_endio); 1811 queue_work(cc->io_queue, &io->work); 1812 return; 1813 } 1814 1815 bio_endio(base_bio); 1816 } 1817 1818 /* 1819 * kcryptd/kcryptd_io: 1820 * 1821 * Needed because it would be very unwise to do decryption in an 1822 * interrupt context. 1823 * 1824 * kcryptd performs the actual encryption or decryption. 1825 * 1826 * kcryptd_io performs the IO submission. 1827 * 1828 * They must be separated as otherwise the final stages could be 1829 * starved by new requests which can block in the first stages due 1830 * to memory allocation. 1831 * 1832 * The work is done per CPU global for all dm-crypt instances. 1833 * They should not depend on each other and do not block. 1834 */ 1835 static void crypt_endio(struct bio *clone) 1836 { 1837 struct dm_crypt_io *io = clone->bi_private; 1838 struct crypt_config *cc = io->cc; 1839 unsigned int rw = bio_data_dir(clone); 1840 blk_status_t error; 1841 1842 /* 1843 * free the processed pages 1844 */ 1845 if (rw == WRITE) 1846 crypt_free_buffer_pages(cc, clone); 1847 1848 error = clone->bi_status; 1849 bio_put(clone); 1850 1851 if (rw == READ && !error) { 1852 kcryptd_queue_crypt(io); 1853 return; 1854 } 1855 1856 if (unlikely(error)) 1857 io->error = error; 1858 1859 crypt_dec_pending(io); 1860 } 1861 1862 #define CRYPT_MAP_READ_GFP GFP_NOWAIT 1863 1864 static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp) 1865 { 1866 struct crypt_config *cc = io->cc; 1867 struct bio *clone; 1868 1869 /* 1870 * We need the original biovec array in order to decrypt the whole bio 1871 * data *afterwards* -- thanks to immutable biovecs we don't need to 1872 * worry about the block layer modifying the biovec array; so leverage 1873 * bio_alloc_clone(). 1874 */ 1875 clone = bio_alloc_clone(cc->dev->bdev, io->base_bio, gfp, &cc->bs); 1876 if (!clone) 1877 return 1; 1878 clone->bi_private = io; 1879 clone->bi_end_io = crypt_endio; 1880 1881 crypt_inc_pending(io); 1882 1883 clone->bi_iter.bi_sector = cc->start + io->sector; 1884 1885 if (dm_crypt_integrity_io_alloc(io, clone)) { 1886 crypt_dec_pending(io); 1887 bio_put(clone); 1888 return 1; 1889 } 1890 1891 dm_submit_bio_remap(io->base_bio, clone); 1892 return 0; 1893 } 1894 1895 static void kcryptd_io_read_work(struct work_struct *work) 1896 { 1897 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 1898 1899 crypt_inc_pending(io); 1900 if (kcryptd_io_read(io, GFP_NOIO)) 1901 io->error = BLK_STS_RESOURCE; 1902 crypt_dec_pending(io); 1903 } 1904 1905 static void kcryptd_queue_read(struct dm_crypt_io *io) 1906 { 1907 struct crypt_config *cc = io->cc; 1908 1909 INIT_WORK(&io->work, kcryptd_io_read_work); 1910 queue_work(cc->io_queue, &io->work); 1911 } 1912 1913 static void kcryptd_io_write(struct dm_crypt_io *io) 1914 { 1915 struct bio *clone = io->ctx.bio_out; 1916 1917 dm_submit_bio_remap(io->base_bio, clone); 1918 } 1919 1920 #define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node) 1921 1922 static int dmcrypt_write(void *data) 1923 { 1924 struct crypt_config *cc = data; 1925 struct dm_crypt_io *io; 1926 1927 while (1) { 1928 struct rb_root write_tree; 1929 struct blk_plug plug; 1930 1931 spin_lock_irq(&cc->write_thread_lock); 1932 continue_locked: 1933 1934 if (!RB_EMPTY_ROOT(&cc->write_tree)) 1935 goto pop_from_list; 1936 1937 set_current_state(TASK_INTERRUPTIBLE); 1938 1939 spin_unlock_irq(&cc->write_thread_lock); 1940 1941 if (unlikely(kthread_should_stop())) { 1942 set_current_state(TASK_RUNNING); 1943 break; 1944 } 1945 1946 schedule(); 1947 1948 set_current_state(TASK_RUNNING); 1949 spin_lock_irq(&cc->write_thread_lock); 1950 goto continue_locked; 1951 1952 pop_from_list: 1953 write_tree = cc->write_tree; 1954 cc->write_tree = RB_ROOT; 1955 spin_unlock_irq(&cc->write_thread_lock); 1956 1957 BUG_ON(rb_parent(write_tree.rb_node)); 1958 1959 /* 1960 * Note: we cannot walk the tree here with rb_next because 1961 * the structures may be freed when kcryptd_io_write is called. 1962 */ 1963 blk_start_plug(&plug); 1964 do { 1965 io = crypt_io_from_node(rb_first(&write_tree)); 1966 rb_erase(&io->rb_node, &write_tree); 1967 kcryptd_io_write(io); 1968 cond_resched(); 1969 } while (!RB_EMPTY_ROOT(&write_tree)); 1970 blk_finish_plug(&plug); 1971 } 1972 return 0; 1973 } 1974 1975 static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async) 1976 { 1977 struct bio *clone = io->ctx.bio_out; 1978 struct crypt_config *cc = io->cc; 1979 unsigned long flags; 1980 sector_t sector; 1981 struct rb_node **rbp, *parent; 1982 1983 if (unlikely(io->error)) { 1984 crypt_free_buffer_pages(cc, clone); 1985 bio_put(clone); 1986 crypt_dec_pending(io); 1987 return; 1988 } 1989 1990 /* crypt_convert should have filled the clone bio */ 1991 BUG_ON(io->ctx.iter_out.bi_size); 1992 1993 clone->bi_iter.bi_sector = cc->start + io->sector; 1994 1995 if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) || 1996 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) { 1997 dm_submit_bio_remap(io->base_bio, clone); 1998 return; 1999 } 2000 2001 spin_lock_irqsave(&cc->write_thread_lock, flags); 2002 if (RB_EMPTY_ROOT(&cc->write_tree)) 2003 wake_up_process(cc->write_thread); 2004 rbp = &cc->write_tree.rb_node; 2005 parent = NULL; 2006 sector = io->sector; 2007 while (*rbp) { 2008 parent = *rbp; 2009 if (sector < crypt_io_from_node(parent)->sector) 2010 rbp = &(*rbp)->rb_left; 2011 else 2012 rbp = &(*rbp)->rb_right; 2013 } 2014 rb_link_node(&io->rb_node, parent, rbp); 2015 rb_insert_color(&io->rb_node, &cc->write_tree); 2016 spin_unlock_irqrestore(&cc->write_thread_lock, flags); 2017 } 2018 2019 static bool kcryptd_crypt_write_inline(struct crypt_config *cc, 2020 struct convert_context *ctx) 2021 2022 { 2023 if (!test_bit(DM_CRYPT_WRITE_INLINE, &cc->flags)) 2024 return false; 2025 2026 /* 2027 * Note: zone append writes (REQ_OP_ZONE_APPEND) do not have ordering 2028 * constraints so they do not need to be issued inline by 2029 * kcryptd_crypt_write_convert(). 2030 */ 2031 switch (bio_op(ctx->bio_in)) { 2032 case REQ_OP_WRITE: 2033 case REQ_OP_WRITE_ZEROES: 2034 return true; 2035 default: 2036 return false; 2037 } 2038 } 2039 2040 static void kcryptd_crypt_write_continue(struct work_struct *work) 2041 { 2042 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2043 struct crypt_config *cc = io->cc; 2044 struct convert_context *ctx = &io->ctx; 2045 int crypt_finished; 2046 sector_t sector = io->sector; 2047 blk_status_t r; 2048 2049 wait_for_completion(&ctx->restart); 2050 reinit_completion(&ctx->restart); 2051 2052 r = crypt_convert(cc, &io->ctx, true, false); 2053 if (r) 2054 io->error = r; 2055 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2056 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2057 /* Wait for completion signaled by kcryptd_async_done() */ 2058 wait_for_completion(&ctx->restart); 2059 crypt_finished = 1; 2060 } 2061 2062 /* Encryption was already finished, submit io now */ 2063 if (crypt_finished) { 2064 kcryptd_crypt_write_io_submit(io, 0); 2065 io->sector = sector; 2066 } 2067 2068 crypt_dec_pending(io); 2069 } 2070 2071 static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) 2072 { 2073 struct crypt_config *cc = io->cc; 2074 struct convert_context *ctx = &io->ctx; 2075 struct bio *clone; 2076 int crypt_finished; 2077 sector_t sector = io->sector; 2078 blk_status_t r; 2079 2080 /* 2081 * Prevent io from disappearing until this function completes. 2082 */ 2083 crypt_inc_pending(io); 2084 crypt_convert_init(cc, ctx, NULL, io->base_bio, sector); 2085 2086 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size); 2087 if (unlikely(!clone)) { 2088 io->error = BLK_STS_IOERR; 2089 goto dec; 2090 } 2091 2092 io->ctx.bio_out = clone; 2093 io->ctx.iter_out = clone->bi_iter; 2094 2095 sector += bio_sectors(clone); 2096 2097 crypt_inc_pending(io); 2098 r = crypt_convert(cc, ctx, 2099 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags), true); 2100 /* 2101 * Crypto API backlogged the request, because its queue was full 2102 * and we're in softirq context, so continue from a workqueue 2103 * (TODO: is it actually possible to be in softirq in the write path?) 2104 */ 2105 if (r == BLK_STS_DEV_RESOURCE) { 2106 INIT_WORK(&io->work, kcryptd_crypt_write_continue); 2107 queue_work(cc->crypt_queue, &io->work); 2108 return; 2109 } 2110 if (r) 2111 io->error = r; 2112 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2113 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2114 /* Wait for completion signaled by kcryptd_async_done() */ 2115 wait_for_completion(&ctx->restart); 2116 crypt_finished = 1; 2117 } 2118 2119 /* Encryption was already finished, submit io now */ 2120 if (crypt_finished) { 2121 kcryptd_crypt_write_io_submit(io, 0); 2122 io->sector = sector; 2123 } 2124 2125 dec: 2126 crypt_dec_pending(io); 2127 } 2128 2129 static void kcryptd_crypt_read_done(struct dm_crypt_io *io) 2130 { 2131 crypt_dec_pending(io); 2132 } 2133 2134 static void kcryptd_crypt_read_continue(struct work_struct *work) 2135 { 2136 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2137 struct crypt_config *cc = io->cc; 2138 blk_status_t r; 2139 2140 wait_for_completion(&io->ctx.restart); 2141 reinit_completion(&io->ctx.restart); 2142 2143 r = crypt_convert(cc, &io->ctx, true, false); 2144 if (r) 2145 io->error = r; 2146 2147 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2148 kcryptd_crypt_read_done(io); 2149 2150 crypt_dec_pending(io); 2151 } 2152 2153 static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) 2154 { 2155 struct crypt_config *cc = io->cc; 2156 blk_status_t r; 2157 2158 crypt_inc_pending(io); 2159 2160 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, 2161 io->sector); 2162 2163 r = crypt_convert(cc, &io->ctx, 2164 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true); 2165 /* 2166 * Crypto API backlogged the request, because its queue was full 2167 * and we're in softirq context, so continue from a workqueue 2168 */ 2169 if (r == BLK_STS_DEV_RESOURCE) { 2170 INIT_WORK(&io->work, kcryptd_crypt_read_continue); 2171 queue_work(cc->crypt_queue, &io->work); 2172 return; 2173 } 2174 if (r) 2175 io->error = r; 2176 2177 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2178 kcryptd_crypt_read_done(io); 2179 2180 crypt_dec_pending(io); 2181 } 2182 2183 static void kcryptd_async_done(void *data, int error) 2184 { 2185 struct dm_crypt_request *dmreq = data; 2186 struct convert_context *ctx = dmreq->ctx; 2187 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 2188 struct crypt_config *cc = io->cc; 2189 2190 /* 2191 * A request from crypto driver backlog is going to be processed now, 2192 * finish the completion and continue in crypt_convert(). 2193 * (Callback will be called for the second time for this request.) 2194 */ 2195 if (error == -EINPROGRESS) { 2196 complete(&ctx->restart); 2197 return; 2198 } 2199 2200 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post) 2201 error = cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq); 2202 2203 if (error == -EBADMSG) { 2204 sector_t s = le64_to_cpu(*org_sector_of_dmreq(cc, dmreq)); 2205 2206 DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu", 2207 ctx->bio_in->bi_bdev, s); 2208 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead", 2209 ctx->bio_in, s, 0); 2210 io->error = BLK_STS_PROTECTION; 2211 } else if (error < 0) 2212 io->error = BLK_STS_IOERR; 2213 2214 crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio); 2215 2216 if (!atomic_dec_and_test(&ctx->cc_pending)) 2217 return; 2218 2219 /* 2220 * The request is fully completed: for inline writes, let 2221 * kcryptd_crypt_write_convert() do the IO submission. 2222 */ 2223 if (bio_data_dir(io->base_bio) == READ) { 2224 kcryptd_crypt_read_done(io); 2225 return; 2226 } 2227 2228 if (kcryptd_crypt_write_inline(cc, ctx)) { 2229 complete(&ctx->restart); 2230 return; 2231 } 2232 2233 kcryptd_crypt_write_io_submit(io, 1); 2234 } 2235 2236 static void kcryptd_crypt(struct work_struct *work) 2237 { 2238 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2239 2240 if (bio_data_dir(io->base_bio) == READ) 2241 kcryptd_crypt_read_convert(io); 2242 else 2243 kcryptd_crypt_write_convert(io); 2244 } 2245 2246 static void kcryptd_crypt_tasklet(unsigned long work) 2247 { 2248 kcryptd_crypt((struct work_struct *)work); 2249 } 2250 2251 static void kcryptd_queue_crypt(struct dm_crypt_io *io) 2252 { 2253 struct crypt_config *cc = io->cc; 2254 2255 if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) || 2256 (bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) { 2257 /* 2258 * in_hardirq(): Crypto API's skcipher_walk_first() refuses to work in hard IRQ context. 2259 * irqs_disabled(): the kernel may run some IO completion from the idle thread, but 2260 * it is being executed with irqs disabled. 2261 */ 2262 if (in_hardirq() || irqs_disabled()) { 2263 io->in_tasklet = true; 2264 tasklet_init(&io->tasklet, kcryptd_crypt_tasklet, (unsigned long)&io->work); 2265 tasklet_schedule(&io->tasklet); 2266 return; 2267 } 2268 2269 kcryptd_crypt(&io->work); 2270 return; 2271 } 2272 2273 INIT_WORK(&io->work, kcryptd_crypt); 2274 queue_work(cc->crypt_queue, &io->work); 2275 } 2276 2277 static void crypt_free_tfms_aead(struct crypt_config *cc) 2278 { 2279 if (!cc->cipher_tfm.tfms_aead) 2280 return; 2281 2282 if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2283 crypto_free_aead(cc->cipher_tfm.tfms_aead[0]); 2284 cc->cipher_tfm.tfms_aead[0] = NULL; 2285 } 2286 2287 kfree(cc->cipher_tfm.tfms_aead); 2288 cc->cipher_tfm.tfms_aead = NULL; 2289 } 2290 2291 static void crypt_free_tfms_skcipher(struct crypt_config *cc) 2292 { 2293 unsigned int i; 2294 2295 if (!cc->cipher_tfm.tfms) 2296 return; 2297 2298 for (i = 0; i < cc->tfms_count; i++) 2299 if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) { 2300 crypto_free_skcipher(cc->cipher_tfm.tfms[i]); 2301 cc->cipher_tfm.tfms[i] = NULL; 2302 } 2303 2304 kfree(cc->cipher_tfm.tfms); 2305 cc->cipher_tfm.tfms = NULL; 2306 } 2307 2308 static void crypt_free_tfms(struct crypt_config *cc) 2309 { 2310 if (crypt_integrity_aead(cc)) 2311 crypt_free_tfms_aead(cc); 2312 else 2313 crypt_free_tfms_skcipher(cc); 2314 } 2315 2316 static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode) 2317 { 2318 unsigned int i; 2319 int err; 2320 2321 cc->cipher_tfm.tfms = kcalloc(cc->tfms_count, 2322 sizeof(struct crypto_skcipher *), 2323 GFP_KERNEL); 2324 if (!cc->cipher_tfm.tfms) 2325 return -ENOMEM; 2326 2327 for (i = 0; i < cc->tfms_count; i++) { 2328 cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0, 2329 CRYPTO_ALG_ALLOCATES_MEMORY); 2330 if (IS_ERR(cc->cipher_tfm.tfms[i])) { 2331 err = PTR_ERR(cc->cipher_tfm.tfms[i]); 2332 crypt_free_tfms(cc); 2333 return err; 2334 } 2335 } 2336 2337 /* 2338 * dm-crypt performance can vary greatly depending on which crypto 2339 * algorithm implementation is used. Help people debug performance 2340 * problems by logging the ->cra_driver_name. 2341 */ 2342 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2343 crypto_skcipher_alg(any_tfm(cc))->base.cra_driver_name); 2344 return 0; 2345 } 2346 2347 static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode) 2348 { 2349 int err; 2350 2351 cc->cipher_tfm.tfms = kmalloc(sizeof(struct crypto_aead *), GFP_KERNEL); 2352 if (!cc->cipher_tfm.tfms) 2353 return -ENOMEM; 2354 2355 cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0, 2356 CRYPTO_ALG_ALLOCATES_MEMORY); 2357 if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2358 err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]); 2359 crypt_free_tfms(cc); 2360 return err; 2361 } 2362 2363 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2364 crypto_aead_alg(any_tfm_aead(cc))->base.cra_driver_name); 2365 return 0; 2366 } 2367 2368 static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode) 2369 { 2370 if (crypt_integrity_aead(cc)) 2371 return crypt_alloc_tfms_aead(cc, ciphermode); 2372 else 2373 return crypt_alloc_tfms_skcipher(cc, ciphermode); 2374 } 2375 2376 static unsigned int crypt_subkey_size(struct crypt_config *cc) 2377 { 2378 return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count); 2379 } 2380 2381 static unsigned int crypt_authenckey_size(struct crypt_config *cc) 2382 { 2383 return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param)); 2384 } 2385 2386 /* 2387 * If AEAD is composed like authenc(hmac(sha256),xts(aes)), 2388 * the key must be for some reason in special format. 2389 * This funcion converts cc->key to this special format. 2390 */ 2391 static void crypt_copy_authenckey(char *p, const void *key, 2392 unsigned int enckeylen, unsigned int authkeylen) 2393 { 2394 struct crypto_authenc_key_param *param; 2395 struct rtattr *rta; 2396 2397 rta = (struct rtattr *)p; 2398 param = RTA_DATA(rta); 2399 param->enckeylen = cpu_to_be32(enckeylen); 2400 rta->rta_len = RTA_LENGTH(sizeof(*param)); 2401 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; 2402 p += RTA_SPACE(sizeof(*param)); 2403 memcpy(p, key + enckeylen, authkeylen); 2404 p += authkeylen; 2405 memcpy(p, key, enckeylen); 2406 } 2407 2408 static int crypt_setkey(struct crypt_config *cc) 2409 { 2410 unsigned int subkey_size; 2411 int err = 0, i, r; 2412 2413 /* Ignore extra keys (which are used for IV etc) */ 2414 subkey_size = crypt_subkey_size(cc); 2415 2416 if (crypt_integrity_hmac(cc)) { 2417 if (subkey_size < cc->key_mac_size) 2418 return -EINVAL; 2419 2420 crypt_copy_authenckey(cc->authenc_key, cc->key, 2421 subkey_size - cc->key_mac_size, 2422 cc->key_mac_size); 2423 } 2424 2425 for (i = 0; i < cc->tfms_count; i++) { 2426 if (crypt_integrity_hmac(cc)) 2427 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2428 cc->authenc_key, crypt_authenckey_size(cc)); 2429 else if (crypt_integrity_aead(cc)) 2430 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2431 cc->key + (i * subkey_size), 2432 subkey_size); 2433 else 2434 r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i], 2435 cc->key + (i * subkey_size), 2436 subkey_size); 2437 if (r) 2438 err = r; 2439 } 2440 2441 if (crypt_integrity_hmac(cc)) 2442 memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc)); 2443 2444 return err; 2445 } 2446 2447 #ifdef CONFIG_KEYS 2448 2449 static bool contains_whitespace(const char *str) 2450 { 2451 while (*str) 2452 if (isspace(*str++)) 2453 return true; 2454 return false; 2455 } 2456 2457 static int set_key_user(struct crypt_config *cc, struct key *key) 2458 { 2459 const struct user_key_payload *ukp; 2460 2461 ukp = user_key_payload_locked(key); 2462 if (!ukp) 2463 return -EKEYREVOKED; 2464 2465 if (cc->key_size != ukp->datalen) 2466 return -EINVAL; 2467 2468 memcpy(cc->key, ukp->data, cc->key_size); 2469 2470 return 0; 2471 } 2472 2473 static int set_key_encrypted(struct crypt_config *cc, struct key *key) 2474 { 2475 const struct encrypted_key_payload *ekp; 2476 2477 ekp = key->payload.data[0]; 2478 if (!ekp) 2479 return -EKEYREVOKED; 2480 2481 if (cc->key_size != ekp->decrypted_datalen) 2482 return -EINVAL; 2483 2484 memcpy(cc->key, ekp->decrypted_data, cc->key_size); 2485 2486 return 0; 2487 } 2488 2489 static int set_key_trusted(struct crypt_config *cc, struct key *key) 2490 { 2491 const struct trusted_key_payload *tkp; 2492 2493 tkp = key->payload.data[0]; 2494 if (!tkp) 2495 return -EKEYREVOKED; 2496 2497 if (cc->key_size != tkp->key_len) 2498 return -EINVAL; 2499 2500 memcpy(cc->key, tkp->key, cc->key_size); 2501 2502 return 0; 2503 } 2504 2505 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2506 { 2507 char *new_key_string, *key_desc; 2508 int ret; 2509 struct key_type *type; 2510 struct key *key; 2511 int (*set_key)(struct crypt_config *cc, struct key *key); 2512 2513 /* 2514 * Reject key_string with whitespace. dm core currently lacks code for 2515 * proper whitespace escaping in arguments on DM_TABLE_STATUS path. 2516 */ 2517 if (contains_whitespace(key_string)) { 2518 DMERR("whitespace chars not allowed in key string"); 2519 return -EINVAL; 2520 } 2521 2522 /* look for next ':' separating key_type from key_description */ 2523 key_desc = strchr(key_string, ':'); 2524 if (!key_desc || key_desc == key_string || !strlen(key_desc + 1)) 2525 return -EINVAL; 2526 2527 if (!strncmp(key_string, "logon:", key_desc - key_string + 1)) { 2528 type = &key_type_logon; 2529 set_key = set_key_user; 2530 } else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) { 2531 type = &key_type_user; 2532 set_key = set_key_user; 2533 } else if (IS_ENABLED(CONFIG_ENCRYPTED_KEYS) && 2534 !strncmp(key_string, "encrypted:", key_desc - key_string + 1)) { 2535 type = &key_type_encrypted; 2536 set_key = set_key_encrypted; 2537 } else if (IS_ENABLED(CONFIG_TRUSTED_KEYS) && 2538 !strncmp(key_string, "trusted:", key_desc - key_string + 1)) { 2539 type = &key_type_trusted; 2540 set_key = set_key_trusted; 2541 } else { 2542 return -EINVAL; 2543 } 2544 2545 new_key_string = kstrdup(key_string, GFP_KERNEL); 2546 if (!new_key_string) 2547 return -ENOMEM; 2548 2549 key = request_key(type, key_desc + 1, NULL); 2550 if (IS_ERR(key)) { 2551 kfree_sensitive(new_key_string); 2552 return PTR_ERR(key); 2553 } 2554 2555 down_read(&key->sem); 2556 2557 ret = set_key(cc, key); 2558 if (ret < 0) { 2559 up_read(&key->sem); 2560 key_put(key); 2561 kfree_sensitive(new_key_string); 2562 return ret; 2563 } 2564 2565 up_read(&key->sem); 2566 key_put(key); 2567 2568 /* clear the flag since following operations may invalidate previously valid key */ 2569 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2570 2571 ret = crypt_setkey(cc); 2572 2573 if (!ret) { 2574 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2575 kfree_sensitive(cc->key_string); 2576 cc->key_string = new_key_string; 2577 } else 2578 kfree_sensitive(new_key_string); 2579 2580 return ret; 2581 } 2582 2583 static int get_key_size(char **key_string) 2584 { 2585 char *colon, dummy; 2586 int ret; 2587 2588 if (*key_string[0] != ':') 2589 return strlen(*key_string) >> 1; 2590 2591 /* look for next ':' in key string */ 2592 colon = strpbrk(*key_string + 1, ":"); 2593 if (!colon) 2594 return -EINVAL; 2595 2596 if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':') 2597 return -EINVAL; 2598 2599 *key_string = colon; 2600 2601 /* remaining key string should be :<logon|user>:<key_desc> */ 2602 2603 return ret; 2604 } 2605 2606 #else 2607 2608 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2609 { 2610 return -EINVAL; 2611 } 2612 2613 static int get_key_size(char **key_string) 2614 { 2615 return (*key_string[0] == ':') ? -EINVAL : (int)(strlen(*key_string) >> 1); 2616 } 2617 2618 #endif /* CONFIG_KEYS */ 2619 2620 static int crypt_set_key(struct crypt_config *cc, char *key) 2621 { 2622 int r = -EINVAL; 2623 int key_string_len = strlen(key); 2624 2625 /* Hyphen (which gives a key_size of zero) means there is no key. */ 2626 if (!cc->key_size && strcmp(key, "-")) 2627 goto out; 2628 2629 /* ':' means the key is in kernel keyring, short-circuit normal key processing */ 2630 if (key[0] == ':') { 2631 r = crypt_set_keyring_key(cc, key + 1); 2632 goto out; 2633 } 2634 2635 /* clear the flag since following operations may invalidate previously valid key */ 2636 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2637 2638 /* wipe references to any kernel keyring key */ 2639 kfree_sensitive(cc->key_string); 2640 cc->key_string = NULL; 2641 2642 /* Decode key from its hex representation. */ 2643 if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0) 2644 goto out; 2645 2646 r = crypt_setkey(cc); 2647 if (!r) 2648 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2649 2650 out: 2651 /* Hex key string not needed after here, so wipe it. */ 2652 memset(key, '0', key_string_len); 2653 2654 return r; 2655 } 2656 2657 static int crypt_wipe_key(struct crypt_config *cc) 2658 { 2659 int r; 2660 2661 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2662 get_random_bytes(&cc->key, cc->key_size); 2663 2664 /* Wipe IV private keys */ 2665 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) { 2666 r = cc->iv_gen_ops->wipe(cc); 2667 if (r) 2668 return r; 2669 } 2670 2671 kfree_sensitive(cc->key_string); 2672 cc->key_string = NULL; 2673 r = crypt_setkey(cc); 2674 memset(&cc->key, 0, cc->key_size * sizeof(u8)); 2675 2676 return r; 2677 } 2678 2679 static void crypt_calculate_pages_per_client(void) 2680 { 2681 unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100; 2682 2683 if (!dm_crypt_clients_n) 2684 return; 2685 2686 pages /= dm_crypt_clients_n; 2687 if (pages < DM_CRYPT_MIN_PAGES_PER_CLIENT) 2688 pages = DM_CRYPT_MIN_PAGES_PER_CLIENT; 2689 dm_crypt_pages_per_client = pages; 2690 } 2691 2692 static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data) 2693 { 2694 struct crypt_config *cc = pool_data; 2695 struct page *page; 2696 2697 /* 2698 * Note, percpu_counter_read_positive() may over (and under) estimate 2699 * the current usage by at most (batch - 1) * num_online_cpus() pages, 2700 * but avoids potential spinlock contention of an exact result. 2701 */ 2702 if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) >= dm_crypt_pages_per_client) && 2703 likely(gfp_mask & __GFP_NORETRY)) 2704 return NULL; 2705 2706 page = alloc_page(gfp_mask); 2707 if (likely(page != NULL)) 2708 percpu_counter_add(&cc->n_allocated_pages, 1); 2709 2710 return page; 2711 } 2712 2713 static void crypt_page_free(void *page, void *pool_data) 2714 { 2715 struct crypt_config *cc = pool_data; 2716 2717 __free_page(page); 2718 percpu_counter_sub(&cc->n_allocated_pages, 1); 2719 } 2720 2721 static void crypt_dtr(struct dm_target *ti) 2722 { 2723 struct crypt_config *cc = ti->private; 2724 2725 ti->private = NULL; 2726 2727 if (!cc) 2728 return; 2729 2730 if (cc->write_thread) 2731 kthread_stop(cc->write_thread); 2732 2733 if (cc->io_queue) 2734 destroy_workqueue(cc->io_queue); 2735 if (cc->crypt_queue) 2736 destroy_workqueue(cc->crypt_queue); 2737 2738 crypt_free_tfms(cc); 2739 2740 bioset_exit(&cc->bs); 2741 2742 mempool_exit(&cc->page_pool); 2743 mempool_exit(&cc->req_pool); 2744 mempool_exit(&cc->tag_pool); 2745 2746 WARN_ON(percpu_counter_sum(&cc->n_allocated_pages) != 0); 2747 percpu_counter_destroy(&cc->n_allocated_pages); 2748 2749 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) 2750 cc->iv_gen_ops->dtr(cc); 2751 2752 if (cc->dev) 2753 dm_put_device(ti, cc->dev); 2754 2755 kfree_sensitive(cc->cipher_string); 2756 kfree_sensitive(cc->key_string); 2757 kfree_sensitive(cc->cipher_auth); 2758 kfree_sensitive(cc->authenc_key); 2759 2760 mutex_destroy(&cc->bio_alloc_lock); 2761 2762 /* Must zero key material before freeing */ 2763 kfree_sensitive(cc); 2764 2765 spin_lock(&dm_crypt_clients_lock); 2766 WARN_ON(!dm_crypt_clients_n); 2767 dm_crypt_clients_n--; 2768 crypt_calculate_pages_per_client(); 2769 spin_unlock(&dm_crypt_clients_lock); 2770 2771 dm_audit_log_dtr(DM_MSG_PREFIX, ti, 1); 2772 } 2773 2774 static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode) 2775 { 2776 struct crypt_config *cc = ti->private; 2777 2778 if (crypt_integrity_aead(cc)) 2779 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2780 else 2781 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2782 2783 if (cc->iv_size) 2784 /* at least a 64 bit sector number should fit in our buffer */ 2785 cc->iv_size = max(cc->iv_size, 2786 (unsigned int)(sizeof(u64) / sizeof(u8))); 2787 else if (ivmode) { 2788 DMWARN("Selected cipher does not support IVs"); 2789 ivmode = NULL; 2790 } 2791 2792 /* Choose ivmode, see comments at iv code. */ 2793 if (ivmode == NULL) 2794 cc->iv_gen_ops = NULL; 2795 else if (strcmp(ivmode, "plain") == 0) 2796 cc->iv_gen_ops = &crypt_iv_plain_ops; 2797 else if (strcmp(ivmode, "plain64") == 0) 2798 cc->iv_gen_ops = &crypt_iv_plain64_ops; 2799 else if (strcmp(ivmode, "plain64be") == 0) 2800 cc->iv_gen_ops = &crypt_iv_plain64be_ops; 2801 else if (strcmp(ivmode, "essiv") == 0) 2802 cc->iv_gen_ops = &crypt_iv_essiv_ops; 2803 else if (strcmp(ivmode, "benbi") == 0) 2804 cc->iv_gen_ops = &crypt_iv_benbi_ops; 2805 else if (strcmp(ivmode, "null") == 0) 2806 cc->iv_gen_ops = &crypt_iv_null_ops; 2807 else if (strcmp(ivmode, "eboiv") == 0) 2808 cc->iv_gen_ops = &crypt_iv_eboiv_ops; 2809 else if (strcmp(ivmode, "elephant") == 0) { 2810 cc->iv_gen_ops = &crypt_iv_elephant_ops; 2811 cc->key_parts = 2; 2812 cc->key_extra_size = cc->key_size / 2; 2813 if (cc->key_extra_size > ELEPHANT_MAX_KEY_SIZE) 2814 return -EINVAL; 2815 set_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags); 2816 } else if (strcmp(ivmode, "lmk") == 0) { 2817 cc->iv_gen_ops = &crypt_iv_lmk_ops; 2818 /* 2819 * Version 2 and 3 is recognised according 2820 * to length of provided multi-key string. 2821 * If present (version 3), last key is used as IV seed. 2822 * All keys (including IV seed) are always the same size. 2823 */ 2824 if (cc->key_size % cc->key_parts) { 2825 cc->key_parts++; 2826 cc->key_extra_size = cc->key_size / cc->key_parts; 2827 } 2828 } else if (strcmp(ivmode, "tcw") == 0) { 2829 cc->iv_gen_ops = &crypt_iv_tcw_ops; 2830 cc->key_parts += 2; /* IV + whitening */ 2831 cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE; 2832 } else if (strcmp(ivmode, "random") == 0) { 2833 cc->iv_gen_ops = &crypt_iv_random_ops; 2834 /* Need storage space in integrity fields. */ 2835 cc->integrity_iv_size = cc->iv_size; 2836 } else { 2837 ti->error = "Invalid IV mode"; 2838 return -EINVAL; 2839 } 2840 2841 return 0; 2842 } 2843 2844 /* 2845 * Workaround to parse HMAC algorithm from AEAD crypto API spec. 2846 * The HMAC is needed to calculate tag size (HMAC digest size). 2847 * This should be probably done by crypto-api calls (once available...) 2848 */ 2849 static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api) 2850 { 2851 char *start, *end, *mac_alg = NULL; 2852 struct crypto_ahash *mac; 2853 2854 if (!strstarts(cipher_api, "authenc(")) 2855 return 0; 2856 2857 start = strchr(cipher_api, '('); 2858 end = strchr(cipher_api, ','); 2859 if (!start || !end || ++start > end) 2860 return -EINVAL; 2861 2862 mac_alg = kzalloc(end - start + 1, GFP_KERNEL); 2863 if (!mac_alg) 2864 return -ENOMEM; 2865 strncpy(mac_alg, start, end - start); 2866 2867 mac = crypto_alloc_ahash(mac_alg, 0, CRYPTO_ALG_ALLOCATES_MEMORY); 2868 kfree(mac_alg); 2869 2870 if (IS_ERR(mac)) 2871 return PTR_ERR(mac); 2872 2873 cc->key_mac_size = crypto_ahash_digestsize(mac); 2874 crypto_free_ahash(mac); 2875 2876 cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL); 2877 if (!cc->authenc_key) 2878 return -ENOMEM; 2879 2880 return 0; 2881 } 2882 2883 static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key, 2884 char **ivmode, char **ivopts) 2885 { 2886 struct crypt_config *cc = ti->private; 2887 char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME]; 2888 int ret = -EINVAL; 2889 2890 cc->tfms_count = 1; 2891 2892 /* 2893 * New format (capi: prefix) 2894 * capi:cipher_api_spec-iv:ivopts 2895 */ 2896 tmp = &cipher_in[strlen("capi:")]; 2897 2898 /* Separate IV options if present, it can contain another '-' in hash name */ 2899 *ivopts = strrchr(tmp, ':'); 2900 if (*ivopts) { 2901 **ivopts = '\0'; 2902 (*ivopts)++; 2903 } 2904 /* Parse IV mode */ 2905 *ivmode = strrchr(tmp, '-'); 2906 if (*ivmode) { 2907 **ivmode = '\0'; 2908 (*ivmode)++; 2909 } 2910 /* The rest is crypto API spec */ 2911 cipher_api = tmp; 2912 2913 /* Alloc AEAD, can be used only in new format. */ 2914 if (crypt_integrity_aead(cc)) { 2915 ret = crypt_ctr_auth_cipher(cc, cipher_api); 2916 if (ret < 0) { 2917 ti->error = "Invalid AEAD cipher spec"; 2918 return ret; 2919 } 2920 } 2921 2922 if (*ivmode && !strcmp(*ivmode, "lmk")) 2923 cc->tfms_count = 64; 2924 2925 if (*ivmode && !strcmp(*ivmode, "essiv")) { 2926 if (!*ivopts) { 2927 ti->error = "Digest algorithm missing for ESSIV mode"; 2928 return -EINVAL; 2929 } 2930 ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)", 2931 cipher_api, *ivopts); 2932 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 2933 ti->error = "Cannot allocate cipher string"; 2934 return -ENOMEM; 2935 } 2936 cipher_api = buf; 2937 } 2938 2939 cc->key_parts = cc->tfms_count; 2940 2941 /* Allocate cipher */ 2942 ret = crypt_alloc_tfms(cc, cipher_api); 2943 if (ret < 0) { 2944 ti->error = "Error allocating crypto tfm"; 2945 return ret; 2946 } 2947 2948 if (crypt_integrity_aead(cc)) 2949 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2950 else 2951 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2952 2953 return 0; 2954 } 2955 2956 static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key, 2957 char **ivmode, char **ivopts) 2958 { 2959 struct crypt_config *cc = ti->private; 2960 char *tmp, *cipher, *chainmode, *keycount; 2961 char *cipher_api = NULL; 2962 int ret = -EINVAL; 2963 char dummy; 2964 2965 if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) { 2966 ti->error = "Bad cipher specification"; 2967 return -EINVAL; 2968 } 2969 2970 /* 2971 * Legacy dm-crypt cipher specification 2972 * cipher[:keycount]-mode-iv:ivopts 2973 */ 2974 tmp = cipher_in; 2975 keycount = strsep(&tmp, "-"); 2976 cipher = strsep(&keycount, ":"); 2977 2978 if (!keycount) 2979 cc->tfms_count = 1; 2980 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 || 2981 !is_power_of_2(cc->tfms_count)) { 2982 ti->error = "Bad cipher key count specification"; 2983 return -EINVAL; 2984 } 2985 cc->key_parts = cc->tfms_count; 2986 2987 chainmode = strsep(&tmp, "-"); 2988 *ivmode = strsep(&tmp, ":"); 2989 *ivopts = tmp; 2990 2991 /* 2992 * For compatibility with the original dm-crypt mapping format, if 2993 * only the cipher name is supplied, use cbc-plain. 2994 */ 2995 if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) { 2996 chainmode = "cbc"; 2997 *ivmode = "plain"; 2998 } 2999 3000 if (strcmp(chainmode, "ecb") && !*ivmode) { 3001 ti->error = "IV mechanism required"; 3002 return -EINVAL; 3003 } 3004 3005 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL); 3006 if (!cipher_api) 3007 goto bad_mem; 3008 3009 if (*ivmode && !strcmp(*ivmode, "essiv")) { 3010 if (!*ivopts) { 3011 ti->error = "Digest algorithm missing for ESSIV mode"; 3012 kfree(cipher_api); 3013 return -EINVAL; 3014 } 3015 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 3016 "essiv(%s(%s),%s)", chainmode, cipher, *ivopts); 3017 } else { 3018 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 3019 "%s(%s)", chainmode, cipher); 3020 } 3021 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 3022 kfree(cipher_api); 3023 goto bad_mem; 3024 } 3025 3026 /* Allocate cipher */ 3027 ret = crypt_alloc_tfms(cc, cipher_api); 3028 if (ret < 0) { 3029 ti->error = "Error allocating crypto tfm"; 3030 kfree(cipher_api); 3031 return ret; 3032 } 3033 kfree(cipher_api); 3034 3035 return 0; 3036 bad_mem: 3037 ti->error = "Cannot allocate cipher strings"; 3038 return -ENOMEM; 3039 } 3040 3041 static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key) 3042 { 3043 struct crypt_config *cc = ti->private; 3044 char *ivmode = NULL, *ivopts = NULL; 3045 int ret; 3046 3047 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL); 3048 if (!cc->cipher_string) { 3049 ti->error = "Cannot allocate cipher strings"; 3050 return -ENOMEM; 3051 } 3052 3053 if (strstarts(cipher_in, "capi:")) 3054 ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts); 3055 else 3056 ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts); 3057 if (ret) 3058 return ret; 3059 3060 /* Initialize IV */ 3061 ret = crypt_ctr_ivmode(ti, ivmode); 3062 if (ret < 0) 3063 return ret; 3064 3065 /* Initialize and set key */ 3066 ret = crypt_set_key(cc, key); 3067 if (ret < 0) { 3068 ti->error = "Error decoding and setting key"; 3069 return ret; 3070 } 3071 3072 /* Allocate IV */ 3073 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) { 3074 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts); 3075 if (ret < 0) { 3076 ti->error = "Error creating IV"; 3077 return ret; 3078 } 3079 } 3080 3081 /* Initialize IV (set keys for ESSIV etc) */ 3082 if (cc->iv_gen_ops && cc->iv_gen_ops->init) { 3083 ret = cc->iv_gen_ops->init(cc); 3084 if (ret < 0) { 3085 ti->error = "Error initialising IV"; 3086 return ret; 3087 } 3088 } 3089 3090 /* wipe the kernel key payload copy */ 3091 if (cc->key_string) 3092 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3093 3094 return ret; 3095 } 3096 3097 static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv) 3098 { 3099 struct crypt_config *cc = ti->private; 3100 struct dm_arg_set as; 3101 static const struct dm_arg _args[] = { 3102 {0, 8, "Invalid number of feature args"}, 3103 }; 3104 unsigned int opt_params, val; 3105 const char *opt_string, *sval; 3106 char dummy; 3107 int ret; 3108 3109 /* Optional parameters */ 3110 as.argc = argc; 3111 as.argv = argv; 3112 3113 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error); 3114 if (ret) 3115 return ret; 3116 3117 while (opt_params--) { 3118 opt_string = dm_shift_arg(&as); 3119 if (!opt_string) { 3120 ti->error = "Not enough feature arguments"; 3121 return -EINVAL; 3122 } 3123 3124 if (!strcasecmp(opt_string, "allow_discards")) 3125 ti->num_discard_bios = 1; 3126 3127 else if (!strcasecmp(opt_string, "same_cpu_crypt")) 3128 set_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3129 3130 else if (!strcasecmp(opt_string, "submit_from_crypt_cpus")) 3131 set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3132 else if (!strcasecmp(opt_string, "no_read_workqueue")) 3133 set_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3134 else if (!strcasecmp(opt_string, "no_write_workqueue")) 3135 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3136 else if (sscanf(opt_string, "integrity:%u:", &val) == 1) { 3137 if (val == 0 || val > MAX_TAG_SIZE) { 3138 ti->error = "Invalid integrity arguments"; 3139 return -EINVAL; 3140 } 3141 cc->on_disk_tag_size = val; 3142 sval = strchr(opt_string + strlen("integrity:"), ':') + 1; 3143 if (!strcasecmp(sval, "aead")) { 3144 set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 3145 } else if (strcasecmp(sval, "none")) { 3146 ti->error = "Unknown integrity profile"; 3147 return -EINVAL; 3148 } 3149 3150 cc->cipher_auth = kstrdup(sval, GFP_KERNEL); 3151 if (!cc->cipher_auth) 3152 return -ENOMEM; 3153 } else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) { 3154 if (cc->sector_size < (1 << SECTOR_SHIFT) || 3155 cc->sector_size > 4096 || 3156 (cc->sector_size & (cc->sector_size - 1))) { 3157 ti->error = "Invalid feature value for sector_size"; 3158 return -EINVAL; 3159 } 3160 if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) { 3161 ti->error = "Device size is not multiple of sector_size feature"; 3162 return -EINVAL; 3163 } 3164 cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT; 3165 } else if (!strcasecmp(opt_string, "iv_large_sectors")) 3166 set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3167 else { 3168 ti->error = "Invalid feature arguments"; 3169 return -EINVAL; 3170 } 3171 } 3172 3173 return 0; 3174 } 3175 3176 #ifdef CONFIG_BLK_DEV_ZONED 3177 static int crypt_report_zones(struct dm_target *ti, 3178 struct dm_report_zones_args *args, unsigned int nr_zones) 3179 { 3180 struct crypt_config *cc = ti->private; 3181 3182 return dm_report_zones(cc->dev->bdev, cc->start, 3183 cc->start + dm_target_offset(ti, args->next_sector), 3184 args, nr_zones); 3185 } 3186 #else 3187 #define crypt_report_zones NULL 3188 #endif 3189 3190 /* 3191 * Construct an encryption mapping: 3192 * <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start> 3193 */ 3194 static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) 3195 { 3196 struct crypt_config *cc; 3197 const char *devname = dm_table_device_name(ti->table); 3198 int key_size; 3199 unsigned int align_mask; 3200 unsigned long long tmpll; 3201 int ret; 3202 size_t iv_size_padding, additional_req_size; 3203 char dummy; 3204 3205 if (argc < 5) { 3206 ti->error = "Not enough arguments"; 3207 return -EINVAL; 3208 } 3209 3210 key_size = get_key_size(&argv[1]); 3211 if (key_size < 0) { 3212 ti->error = "Cannot parse key size"; 3213 return -EINVAL; 3214 } 3215 3216 cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL); 3217 if (!cc) { 3218 ti->error = "Cannot allocate encryption context"; 3219 return -ENOMEM; 3220 } 3221 cc->key_size = key_size; 3222 cc->sector_size = (1 << SECTOR_SHIFT); 3223 cc->sector_shift = 0; 3224 3225 ti->private = cc; 3226 3227 spin_lock(&dm_crypt_clients_lock); 3228 dm_crypt_clients_n++; 3229 crypt_calculate_pages_per_client(); 3230 spin_unlock(&dm_crypt_clients_lock); 3231 3232 ret = percpu_counter_init(&cc->n_allocated_pages, 0, GFP_KERNEL); 3233 if (ret < 0) 3234 goto bad; 3235 3236 /* Optional parameters need to be read before cipher constructor */ 3237 if (argc > 5) { 3238 ret = crypt_ctr_optional(ti, argc - 5, &argv[5]); 3239 if (ret) 3240 goto bad; 3241 } 3242 3243 ret = crypt_ctr_cipher(ti, argv[0], argv[1]); 3244 if (ret < 0) 3245 goto bad; 3246 3247 if (crypt_integrity_aead(cc)) { 3248 cc->dmreq_start = sizeof(struct aead_request); 3249 cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc)); 3250 align_mask = crypto_aead_alignmask(any_tfm_aead(cc)); 3251 } else { 3252 cc->dmreq_start = sizeof(struct skcipher_request); 3253 cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc)); 3254 align_mask = crypto_skcipher_alignmask(any_tfm(cc)); 3255 } 3256 cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request)); 3257 3258 if (align_mask < CRYPTO_MINALIGN) { 3259 /* Allocate the padding exactly */ 3260 iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request)) 3261 & align_mask; 3262 } else { 3263 /* 3264 * If the cipher requires greater alignment than kmalloc 3265 * alignment, we don't know the exact position of the 3266 * initialization vector. We must assume worst case. 3267 */ 3268 iv_size_padding = align_mask; 3269 } 3270 3271 /* ...| IV + padding | original IV | original sec. number | bio tag offset | */ 3272 additional_req_size = sizeof(struct dm_crypt_request) + 3273 iv_size_padding + cc->iv_size + 3274 cc->iv_size + 3275 sizeof(uint64_t) + 3276 sizeof(unsigned int); 3277 3278 ret = mempool_init_kmalloc_pool(&cc->req_pool, MIN_IOS, cc->dmreq_start + additional_req_size); 3279 if (ret) { 3280 ti->error = "Cannot allocate crypt request mempool"; 3281 goto bad; 3282 } 3283 3284 cc->per_bio_data_size = ti->per_io_data_size = 3285 ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size, 3286 ARCH_DMA_MINALIGN); 3287 3288 ret = mempool_init(&cc->page_pool, BIO_MAX_VECS, crypt_page_alloc, crypt_page_free, cc); 3289 if (ret) { 3290 ti->error = "Cannot allocate page mempool"; 3291 goto bad; 3292 } 3293 3294 ret = bioset_init(&cc->bs, MIN_IOS, 0, BIOSET_NEED_BVECS); 3295 if (ret) { 3296 ti->error = "Cannot allocate crypt bioset"; 3297 goto bad; 3298 } 3299 3300 mutex_init(&cc->bio_alloc_lock); 3301 3302 ret = -EINVAL; 3303 if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) || 3304 (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) { 3305 ti->error = "Invalid iv_offset sector"; 3306 goto bad; 3307 } 3308 cc->iv_offset = tmpll; 3309 3310 ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev); 3311 if (ret) { 3312 ti->error = "Device lookup failed"; 3313 goto bad; 3314 } 3315 3316 ret = -EINVAL; 3317 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) { 3318 ti->error = "Invalid device sector"; 3319 goto bad; 3320 } 3321 cc->start = tmpll; 3322 3323 if (bdev_is_zoned(cc->dev->bdev)) { 3324 /* 3325 * For zoned block devices, we need to preserve the issuer write 3326 * ordering. To do so, disable write workqueues and force inline 3327 * encryption completion. 3328 */ 3329 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3330 set_bit(DM_CRYPT_WRITE_INLINE, &cc->flags); 3331 3332 /* 3333 * All zone append writes to a zone of a zoned block device will 3334 * have the same BIO sector, the start of the zone. When the 3335 * cypher IV mode uses sector values, all data targeting a 3336 * zone will be encrypted using the first sector numbers of the 3337 * zone. This will not result in write errors but will 3338 * cause most reads to fail as reads will use the sector values 3339 * for the actual data locations, resulting in IV mismatch. 3340 * To avoid this problem, ask DM core to emulate zone append 3341 * operations with regular writes. 3342 */ 3343 DMDEBUG("Zone append operations will be emulated"); 3344 ti->emulate_zone_append = true; 3345 } 3346 3347 if (crypt_integrity_aead(cc) || cc->integrity_iv_size) { 3348 ret = crypt_integrity_ctr(cc, ti); 3349 if (ret) 3350 goto bad; 3351 3352 cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->on_disk_tag_size; 3353 if (!cc->tag_pool_max_sectors) 3354 cc->tag_pool_max_sectors = 1; 3355 3356 ret = mempool_init_kmalloc_pool(&cc->tag_pool, MIN_IOS, 3357 cc->tag_pool_max_sectors * cc->on_disk_tag_size); 3358 if (ret) { 3359 ti->error = "Cannot allocate integrity tags mempool"; 3360 goto bad; 3361 } 3362 3363 cc->tag_pool_max_sectors <<= cc->sector_shift; 3364 } 3365 3366 ret = -ENOMEM; 3367 cc->io_queue = alloc_workqueue("kcryptd_io/%s", WQ_MEM_RECLAIM, 1, devname); 3368 if (!cc->io_queue) { 3369 ti->error = "Couldn't create kcryptd io queue"; 3370 goto bad; 3371 } 3372 3373 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3374 cc->crypt_queue = alloc_workqueue("kcryptd/%s", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM, 3375 1, devname); 3376 else 3377 cc->crypt_queue = alloc_workqueue("kcryptd/%s", 3378 WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND, 3379 num_online_cpus(), devname); 3380 if (!cc->crypt_queue) { 3381 ti->error = "Couldn't create kcryptd queue"; 3382 goto bad; 3383 } 3384 3385 spin_lock_init(&cc->write_thread_lock); 3386 cc->write_tree = RB_ROOT; 3387 3388 cc->write_thread = kthread_run(dmcrypt_write, cc, "dmcrypt_write/%s", devname); 3389 if (IS_ERR(cc->write_thread)) { 3390 ret = PTR_ERR(cc->write_thread); 3391 cc->write_thread = NULL; 3392 ti->error = "Couldn't spawn write thread"; 3393 goto bad; 3394 } 3395 3396 ti->num_flush_bios = 1; 3397 ti->limit_swap_bios = true; 3398 ti->accounts_remapped_io = true; 3399 3400 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 1); 3401 return 0; 3402 3403 bad: 3404 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 0); 3405 crypt_dtr(ti); 3406 return ret; 3407 } 3408 3409 static int crypt_map(struct dm_target *ti, struct bio *bio) 3410 { 3411 struct dm_crypt_io *io; 3412 struct crypt_config *cc = ti->private; 3413 3414 /* 3415 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues. 3416 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight 3417 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters 3418 */ 3419 if (unlikely(bio->bi_opf & REQ_PREFLUSH || 3420 bio_op(bio) == REQ_OP_DISCARD)) { 3421 bio_set_dev(bio, cc->dev->bdev); 3422 if (bio_sectors(bio)) 3423 bio->bi_iter.bi_sector = cc->start + 3424 dm_target_offset(ti, bio->bi_iter.bi_sector); 3425 return DM_MAPIO_REMAPPED; 3426 } 3427 3428 /* 3429 * Check if bio is too large, split as needed. 3430 */ 3431 if (unlikely(bio->bi_iter.bi_size > (BIO_MAX_VECS << PAGE_SHIFT)) && 3432 (bio_data_dir(bio) == WRITE || cc->on_disk_tag_size)) 3433 dm_accept_partial_bio(bio, ((BIO_MAX_VECS << PAGE_SHIFT) >> SECTOR_SHIFT)); 3434 3435 /* 3436 * Ensure that bio is a multiple of internal sector encryption size 3437 * and is aligned to this size as defined in IO hints. 3438 */ 3439 if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0)) 3440 return DM_MAPIO_KILL; 3441 3442 if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1))) 3443 return DM_MAPIO_KILL; 3444 3445 io = dm_per_bio_data(bio, cc->per_bio_data_size); 3446 crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector)); 3447 3448 if (cc->on_disk_tag_size) { 3449 unsigned int tag_len = cc->on_disk_tag_size * (bio_sectors(bio) >> cc->sector_shift); 3450 3451 if (unlikely(tag_len > KMALLOC_MAX_SIZE)) 3452 io->integrity_metadata = NULL; 3453 else 3454 io->integrity_metadata = kmalloc(tag_len, GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN); 3455 3456 if (unlikely(!io->integrity_metadata)) { 3457 if (bio_sectors(bio) > cc->tag_pool_max_sectors) 3458 dm_accept_partial_bio(bio, cc->tag_pool_max_sectors); 3459 io->integrity_metadata = mempool_alloc(&cc->tag_pool, GFP_NOIO); 3460 io->integrity_metadata_from_pool = true; 3461 } 3462 } 3463 3464 if (crypt_integrity_aead(cc)) 3465 io->ctx.r.req_aead = (struct aead_request *)(io + 1); 3466 else 3467 io->ctx.r.req = (struct skcipher_request *)(io + 1); 3468 3469 if (bio_data_dir(io->base_bio) == READ) { 3470 if (kcryptd_io_read(io, CRYPT_MAP_READ_GFP)) 3471 kcryptd_queue_read(io); 3472 } else 3473 kcryptd_queue_crypt(io); 3474 3475 return DM_MAPIO_SUBMITTED; 3476 } 3477 3478 static char hex2asc(unsigned char c) 3479 { 3480 return c + '0' + ((unsigned int)(9 - c) >> 4 & 0x27); 3481 } 3482 3483 static void crypt_status(struct dm_target *ti, status_type_t type, 3484 unsigned int status_flags, char *result, unsigned int maxlen) 3485 { 3486 struct crypt_config *cc = ti->private; 3487 unsigned int i, sz = 0; 3488 int num_feature_args = 0; 3489 3490 switch (type) { 3491 case STATUSTYPE_INFO: 3492 result[0] = '\0'; 3493 break; 3494 3495 case STATUSTYPE_TABLE: 3496 DMEMIT("%s ", cc->cipher_string); 3497 3498 if (cc->key_size > 0) { 3499 if (cc->key_string) 3500 DMEMIT(":%u:%s", cc->key_size, cc->key_string); 3501 else { 3502 for (i = 0; i < cc->key_size; i++) { 3503 DMEMIT("%c%c", hex2asc(cc->key[i] >> 4), 3504 hex2asc(cc->key[i] & 0xf)); 3505 } 3506 } 3507 } else 3508 DMEMIT("-"); 3509 3510 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, 3511 cc->dev->name, (unsigned long long)cc->start); 3512 3513 num_feature_args += !!ti->num_discard_bios; 3514 num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3515 num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3516 num_feature_args += test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3517 num_feature_args += test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3518 num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT); 3519 num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3520 if (cc->on_disk_tag_size) 3521 num_feature_args++; 3522 if (num_feature_args) { 3523 DMEMIT(" %d", num_feature_args); 3524 if (ti->num_discard_bios) 3525 DMEMIT(" allow_discards"); 3526 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3527 DMEMIT(" same_cpu_crypt"); 3528 if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) 3529 DMEMIT(" submit_from_crypt_cpus"); 3530 if (test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) 3531 DMEMIT(" no_read_workqueue"); 3532 if (test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) 3533 DMEMIT(" no_write_workqueue"); 3534 if (cc->on_disk_tag_size) 3535 DMEMIT(" integrity:%u:%s", cc->on_disk_tag_size, cc->cipher_auth); 3536 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3537 DMEMIT(" sector_size:%d", cc->sector_size); 3538 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 3539 DMEMIT(" iv_large_sectors"); 3540 } 3541 break; 3542 3543 case STATUSTYPE_IMA: 3544 DMEMIT_TARGET_NAME_VERSION(ti->type); 3545 DMEMIT(",allow_discards=%c", ti->num_discard_bios ? 'y' : 'n'); 3546 DMEMIT(",same_cpu_crypt=%c", test_bit(DM_CRYPT_SAME_CPU, &cc->flags) ? 'y' : 'n'); 3547 DMEMIT(",submit_from_crypt_cpus=%c", test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags) ? 3548 'y' : 'n'); 3549 DMEMIT(",no_read_workqueue=%c", test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags) ? 3550 'y' : 'n'); 3551 DMEMIT(",no_write_workqueue=%c", test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags) ? 3552 'y' : 'n'); 3553 DMEMIT(",iv_large_sectors=%c", test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags) ? 3554 'y' : 'n'); 3555 3556 if (cc->on_disk_tag_size) 3557 DMEMIT(",integrity_tag_size=%u,cipher_auth=%s", 3558 cc->on_disk_tag_size, cc->cipher_auth); 3559 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3560 DMEMIT(",sector_size=%d", cc->sector_size); 3561 if (cc->cipher_string) 3562 DMEMIT(",cipher_string=%s", cc->cipher_string); 3563 3564 DMEMIT(",key_size=%u", cc->key_size); 3565 DMEMIT(",key_parts=%u", cc->key_parts); 3566 DMEMIT(",key_extra_size=%u", cc->key_extra_size); 3567 DMEMIT(",key_mac_size=%u", cc->key_mac_size); 3568 DMEMIT(";"); 3569 break; 3570 } 3571 } 3572 3573 static void crypt_postsuspend(struct dm_target *ti) 3574 { 3575 struct crypt_config *cc = ti->private; 3576 3577 set_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3578 } 3579 3580 static int crypt_preresume(struct dm_target *ti) 3581 { 3582 struct crypt_config *cc = ti->private; 3583 3584 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { 3585 DMERR("aborting resume - crypt key is not set."); 3586 return -EAGAIN; 3587 } 3588 3589 return 0; 3590 } 3591 3592 static void crypt_resume(struct dm_target *ti) 3593 { 3594 struct crypt_config *cc = ti->private; 3595 3596 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3597 } 3598 3599 /* Message interface 3600 * key set <key> 3601 * key wipe 3602 */ 3603 static int crypt_message(struct dm_target *ti, unsigned int argc, char **argv, 3604 char *result, unsigned int maxlen) 3605 { 3606 struct crypt_config *cc = ti->private; 3607 int key_size, ret = -EINVAL; 3608 3609 if (argc < 2) 3610 goto error; 3611 3612 if (!strcasecmp(argv[0], "key")) { 3613 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { 3614 DMWARN("not suspended during key manipulation."); 3615 return -EINVAL; 3616 } 3617 if (argc == 3 && !strcasecmp(argv[1], "set")) { 3618 /* The key size may not be changed. */ 3619 key_size = get_key_size(&argv[2]); 3620 if (key_size < 0 || cc->key_size != key_size) { 3621 memset(argv[2], '0', strlen(argv[2])); 3622 return -EINVAL; 3623 } 3624 3625 ret = crypt_set_key(cc, argv[2]); 3626 if (ret) 3627 return ret; 3628 if (cc->iv_gen_ops && cc->iv_gen_ops->init) 3629 ret = cc->iv_gen_ops->init(cc); 3630 /* wipe the kernel key payload copy */ 3631 if (cc->key_string) 3632 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3633 return ret; 3634 } 3635 if (argc == 2 && !strcasecmp(argv[1], "wipe")) 3636 return crypt_wipe_key(cc); 3637 } 3638 3639 error: 3640 DMWARN("unrecognised message received."); 3641 return -EINVAL; 3642 } 3643 3644 static int crypt_iterate_devices(struct dm_target *ti, 3645 iterate_devices_callout_fn fn, void *data) 3646 { 3647 struct crypt_config *cc = ti->private; 3648 3649 return fn(ti, cc->dev, cc->start, ti->len, data); 3650 } 3651 3652 static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits) 3653 { 3654 struct crypt_config *cc = ti->private; 3655 3656 /* 3657 * Unfortunate constraint that is required to avoid the potential 3658 * for exceeding underlying device's max_segments limits -- due to 3659 * crypt_alloc_buffer() possibly allocating pages for the encryption 3660 * bio that are not as physically contiguous as the original bio. 3661 */ 3662 limits->max_segment_size = PAGE_SIZE; 3663 3664 limits->logical_block_size = 3665 max_t(unsigned int, limits->logical_block_size, cc->sector_size); 3666 limits->physical_block_size = 3667 max_t(unsigned int, limits->physical_block_size, cc->sector_size); 3668 limits->io_min = max_t(unsigned int, limits->io_min, cc->sector_size); 3669 limits->dma_alignment = limits->logical_block_size - 1; 3670 } 3671 3672 static struct target_type crypt_target = { 3673 .name = "crypt", 3674 .version = {1, 24, 0}, 3675 .module = THIS_MODULE, 3676 .ctr = crypt_ctr, 3677 .dtr = crypt_dtr, 3678 .features = DM_TARGET_ZONED_HM, 3679 .report_zones = crypt_report_zones, 3680 .map = crypt_map, 3681 .status = crypt_status, 3682 .postsuspend = crypt_postsuspend, 3683 .preresume = crypt_preresume, 3684 .resume = crypt_resume, 3685 .message = crypt_message, 3686 .iterate_devices = crypt_iterate_devices, 3687 .io_hints = crypt_io_hints, 3688 }; 3689 module_dm(crypt); 3690 3691 MODULE_AUTHOR("Jana Saout <jana@saout.de>"); 3692 MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); 3693 MODULE_LICENSE("GPL"); 3694