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