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 50static DEFINE_IDA(workqueue_ida); 51 52/* 53 * context holding the current state of a multi-part conversion 54 */ 55struct convert_context { 56 struct completion restart; 57 struct bio *bio_in; 58 struct bvec_iter iter_in; 59 struct bio *bio_out; 60 struct bvec_iter iter_out; 61 atomic_t cc_pending; 62 u64 cc_sector; 63 union { 64 struct skcipher_request *req; 65 struct aead_request *req_aead; 66 } r; 67 bool aead_recheck; 68 bool aead_failed; 69 70}; 71 72/* 73 * per bio private data 74 */ 75struct dm_crypt_io { 76 struct crypt_config *cc; 77 struct bio *base_bio; 78 u8 *integrity_metadata; 79 bool integrity_metadata_from_pool:1; 80 81 struct work_struct work; 82 83 struct convert_context ctx; 84 85 atomic_t io_pending; 86 blk_status_t error; 87 sector_t sector; 88 89 struct bvec_iter saved_bi_iter; 90 91 struct rb_node rb_node; 92} CRYPTO_MINALIGN_ATTR; 93 94struct dm_crypt_request { 95 struct convert_context *ctx; 96 struct scatterlist sg_in[4]; 97 struct scatterlist sg_out[4]; 98 u64 iv_sector; 99}; 100 101struct crypt_config; 102 103struct crypt_iv_operations { 104 int (*ctr)(struct crypt_config *cc, struct dm_target *ti, 105 const char *opts); 106 void (*dtr)(struct crypt_config *cc); 107 int (*init)(struct crypt_config *cc); 108 int (*wipe)(struct crypt_config *cc); 109 int (*generator)(struct crypt_config *cc, u8 *iv, 110 struct dm_crypt_request *dmreq); 111 int (*post)(struct crypt_config *cc, u8 *iv, 112 struct dm_crypt_request *dmreq); 113}; 114 115struct iv_benbi_private { 116 int shift; 117}; 118 119#define LMK_SEED_SIZE 64 /* hash + 0 */ 120struct iv_lmk_private { 121 struct crypto_shash *hash_tfm; 122 u8 *seed; 123}; 124 125#define TCW_WHITENING_SIZE 16 126struct iv_tcw_private { 127 struct crypto_shash *crc32_tfm; 128 u8 *iv_seed; 129 u8 *whitening; 130}; 131 132#define ELEPHANT_MAX_KEY_SIZE 32 133struct iv_elephant_private { 134 struct crypto_skcipher *tfm; 135}; 136 137/* 138 * Crypt: maps a linear range of a block device 139 * and encrypts / decrypts at the same time. 140 */ 141enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID, 142 DM_CRYPT_SAME_CPU, DM_CRYPT_HIGH_PRIORITY, 143 DM_CRYPT_NO_OFFLOAD, DM_CRYPT_NO_READ_WORKQUEUE, 144 DM_CRYPT_NO_WRITE_WORKQUEUE, DM_CRYPT_WRITE_INLINE }; 145 146enum cipher_flags { 147 CRYPT_MODE_INTEGRITY_AEAD, /* Use authenticated mode for cipher */ 148 CRYPT_IV_LARGE_SECTORS, /* Calculate IV from sector_size, not 512B sectors */ 149 CRYPT_ENCRYPT_PREPROCESS, /* Must preprocess data for encryption (elephant) */ 150}; 151 152/* 153 * The fields in here must be read only after initialization. 154 */ 155struct crypt_config { 156 struct dm_dev *dev; 157 sector_t start; 158 159 struct percpu_counter n_allocated_pages; 160 161 struct workqueue_struct *io_queue; 162 struct workqueue_struct *crypt_queue; 163 164 spinlock_t write_thread_lock; 165 struct task_struct *write_thread; 166 struct rb_root write_tree; 167 168 char *cipher_string; 169 char *cipher_auth; 170 char *key_string; 171 172 const struct crypt_iv_operations *iv_gen_ops; 173 union { 174 struct iv_benbi_private benbi; 175 struct iv_lmk_private lmk; 176 struct iv_tcw_private tcw; 177 struct iv_elephant_private elephant; 178 } iv_gen_private; 179 u64 iv_offset; 180 unsigned int iv_size; 181 unsigned short sector_size; 182 unsigned char sector_shift; 183 184 union { 185 struct crypto_skcipher **tfms; 186 struct crypto_aead **tfms_aead; 187 } cipher_tfm; 188 unsigned int tfms_count; 189 int workqueue_id; 190 unsigned long cipher_flags; 191 192 /* 193 * Layout of each crypto request: 194 * 195 * struct skcipher_request 196 * context 197 * padding 198 * struct dm_crypt_request 199 * padding 200 * IV 201 * 202 * The padding is added so that dm_crypt_request and the IV are 203 * correctly aligned. 204 */ 205 unsigned int dmreq_start; 206 207 unsigned int per_bio_data_size; 208 209 unsigned long flags; 210 unsigned int key_size; 211 unsigned int key_parts; /* independent parts in key buffer */ 212 unsigned int key_extra_size; /* additional keys length */ 213 unsigned int key_mac_size; /* MAC key size for authenc(...) */ 214 215 unsigned int integrity_tag_size; 216 unsigned int integrity_iv_size; 217 unsigned int on_disk_tag_size; 218 219 /* 220 * pool for per bio private data, crypto requests, 221 * encryption requeusts/buffer pages and integrity tags 222 */ 223 unsigned int tag_pool_max_sectors; 224 mempool_t tag_pool; 225 mempool_t req_pool; 226 mempool_t page_pool; 227 228 struct bio_set bs; 229 struct mutex bio_alloc_lock; 230 231 u8 *authenc_key; /* space for keys in authenc() format (if used) */ 232 u8 key[] __counted_by(key_size); 233}; 234 235#define MIN_IOS 64 236#define MAX_TAG_SIZE 480 237#define POOL_ENTRY_SIZE 512 238 239static DEFINE_SPINLOCK(dm_crypt_clients_lock); 240static unsigned int dm_crypt_clients_n; 241static volatile unsigned long dm_crypt_pages_per_client; 242#define DM_CRYPT_MEMORY_PERCENT 2 243#define DM_CRYPT_MIN_PAGES_PER_CLIENT (BIO_MAX_VECS * 16) 244 245static void crypt_endio(struct bio *clone); 246static void kcryptd_queue_crypt(struct dm_crypt_io *io); 247static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 248 struct scatterlist *sg); 249 250static bool crypt_integrity_aead(struct crypt_config *cc); 251 252/* 253 * Use this to access cipher attributes that are independent of the key. 254 */ 255static struct crypto_skcipher *any_tfm(struct crypt_config *cc) 256{ 257 return cc->cipher_tfm.tfms[0]; 258} 259 260static struct crypto_aead *any_tfm_aead(struct crypt_config *cc) 261{ 262 return cc->cipher_tfm.tfms_aead[0]; 263} 264 265/* 266 * Different IV generation algorithms: 267 * 268 * plain: the initial vector is the 32-bit little-endian version of the sector 269 * number, padded with zeros if necessary. 270 * 271 * plain64: the initial vector is the 64-bit little-endian version of the sector 272 * number, padded with zeros if necessary. 273 * 274 * plain64be: the initial vector is the 64-bit big-endian version of the sector 275 * number, padded with zeros if necessary. 276 * 277 * essiv: "encrypted sector|salt initial vector", the sector number is 278 * encrypted with the bulk cipher using a salt as key. The salt 279 * should be derived from the bulk cipher's key via hashing. 280 * 281 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 282 * (needed for LRW-32-AES and possible other narrow block modes) 283 * 284 * null: the initial vector is always zero. Provides compatibility with 285 * obsolete loop_fish2 devices. Do not use for new devices. 286 * 287 * lmk: Compatible implementation of the block chaining mode used 288 * by the Loop-AES block device encryption system 289 * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/ 290 * It operates on full 512 byte sectors and uses CBC 291 * with an IV derived from the sector number, the data and 292 * optionally extra IV seed. 293 * This means that after decryption the first block 294 * of sector must be tweaked according to decrypted data. 295 * Loop-AES can use three encryption schemes: 296 * version 1: is plain aes-cbc mode 297 * version 2: uses 64 multikey scheme with lmk IV generator 298 * version 3: the same as version 2 with additional IV seed 299 * (it uses 65 keys, last key is used as IV seed) 300 * 301 * tcw: Compatible implementation of the block chaining mode used 302 * by the TrueCrypt device encryption system (prior to version 4.1). 303 * For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat 304 * It operates on full 512 byte sectors and uses CBC 305 * with an IV derived from initial key and the sector number. 306 * In addition, whitening value is applied on every sector, whitening 307 * is calculated from initial key, sector number and mixed using CRC32. 308 * Note that this encryption scheme is vulnerable to watermarking attacks 309 * and should be used for old compatible containers access only. 310 * 311 * eboiv: Encrypted byte-offset IV (used in Bitlocker in CBC mode) 312 * The IV is encrypted little-endian byte-offset (with the same key 313 * and cipher as the volume). 314 * 315 * elephant: The extended version of eboiv with additional Elephant diffuser 316 * used with Bitlocker CBC mode. 317 * This mode was used in older Windows systems 318 * https://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf 319 */ 320 321static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, 322 struct dm_crypt_request *dmreq) 323{ 324 memset(iv, 0, cc->iv_size); 325 *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff); 326 327 return 0; 328} 329 330static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv, 331 struct dm_crypt_request *dmreq) 332{ 333 memset(iv, 0, cc->iv_size); 334 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 335 336 return 0; 337} 338 339static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv, 340 struct dm_crypt_request *dmreq) 341{ 342 memset(iv, 0, cc->iv_size); 343 /* iv_size is at least of size u64; usually it is 16 bytes */ 344 *(__be64 *)&iv[cc->iv_size - sizeof(u64)] = cpu_to_be64(dmreq->iv_sector); 345 346 return 0; 347} 348 349static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, 350 struct dm_crypt_request *dmreq) 351{ 352 /* 353 * ESSIV encryption of the IV is now handled by the crypto API, 354 * so just pass the plain sector number here. 355 */ 356 memset(iv, 0, cc->iv_size); 357 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 358 359 return 0; 360} 361 362static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, 363 const char *opts) 364{ 365 unsigned int bs; 366 int log; 367 368 if (crypt_integrity_aead(cc)) 369 bs = crypto_aead_blocksize(any_tfm_aead(cc)); 370 else 371 bs = crypto_skcipher_blocksize(any_tfm(cc)); 372 log = ilog2(bs); 373 374 /* 375 * We need to calculate how far we must shift the sector count 376 * to get the cipher block count, we use this shift in _gen. 377 */ 378 if (1 << log != bs) { 379 ti->error = "cypher blocksize is not a power of 2"; 380 return -EINVAL; 381 } 382 383 if (log > 9) { 384 ti->error = "cypher blocksize is > 512"; 385 return -EINVAL; 386 } 387 388 cc->iv_gen_private.benbi.shift = 9 - log; 389 390 return 0; 391} 392 393static void crypt_iv_benbi_dtr(struct crypt_config *cc) 394{ 395} 396 397static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, 398 struct dm_crypt_request *dmreq) 399{ 400 __be64 val; 401 402 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ 403 404 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1); 405 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); 406 407 return 0; 408} 409 410static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, 411 struct dm_crypt_request *dmreq) 412{ 413 memset(iv, 0, cc->iv_size); 414 415 return 0; 416} 417 418static void crypt_iv_lmk_dtr(struct crypt_config *cc) 419{ 420 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 421 422 if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm)) 423 crypto_free_shash(lmk->hash_tfm); 424 lmk->hash_tfm = NULL; 425 426 kfree_sensitive(lmk->seed); 427 lmk->seed = NULL; 428} 429 430static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti, 431 const char *opts) 432{ 433 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 434 435 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 436 ti->error = "Unsupported sector size for LMK"; 437 return -EINVAL; 438 } 439 440 lmk->hash_tfm = crypto_alloc_shash("md5", 0, 441 CRYPTO_ALG_ALLOCATES_MEMORY); 442 if (IS_ERR(lmk->hash_tfm)) { 443 ti->error = "Error initializing LMK hash"; 444 return PTR_ERR(lmk->hash_tfm); 445 } 446 447 /* No seed in LMK version 2 */ 448 if (cc->key_parts == cc->tfms_count) { 449 lmk->seed = NULL; 450 return 0; 451 } 452 453 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL); 454 if (!lmk->seed) { 455 crypt_iv_lmk_dtr(cc); 456 ti->error = "Error kmallocing seed storage in LMK"; 457 return -ENOMEM; 458 } 459 460 return 0; 461} 462 463static int crypt_iv_lmk_init(struct crypt_config *cc) 464{ 465 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 466 int subkey_size = cc->key_size / cc->key_parts; 467 468 /* LMK seed is on the position of LMK_KEYS + 1 key */ 469 if (lmk->seed) 470 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size), 471 crypto_shash_digestsize(lmk->hash_tfm)); 472 473 return 0; 474} 475 476static int crypt_iv_lmk_wipe(struct crypt_config *cc) 477{ 478 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 479 480 if (lmk->seed) 481 memset(lmk->seed, 0, LMK_SEED_SIZE); 482 483 return 0; 484} 485 486static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv, 487 struct dm_crypt_request *dmreq, 488 u8 *data) 489{ 490 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 491 SHASH_DESC_ON_STACK(desc, lmk->hash_tfm); 492 struct md5_state md5state; 493 __le32 buf[4]; 494 int i, r; 495 496 desc->tfm = lmk->hash_tfm; 497 498 r = crypto_shash_init(desc); 499 if (r) 500 return r; 501 502 if (lmk->seed) { 503 r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE); 504 if (r) 505 return r; 506 } 507 508 /* Sector is always 512B, block size 16, add data of blocks 1-31 */ 509 r = crypto_shash_update(desc, data + 16, 16 * 31); 510 if (r) 511 return r; 512 513 /* Sector is cropped to 56 bits here */ 514 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF); 515 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000); 516 buf[2] = cpu_to_le32(4024); 517 buf[3] = 0; 518 r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf)); 519 if (r) 520 return r; 521 522 /* No MD5 padding here */ 523 r = crypto_shash_export(desc, &md5state); 524 if (r) 525 return r; 526 527 for (i = 0; i < MD5_HASH_WORDS; i++) 528 __cpu_to_le32s(&md5state.hash[i]); 529 memcpy(iv, &md5state.hash, cc->iv_size); 530 531 return 0; 532} 533 534static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv, 535 struct dm_crypt_request *dmreq) 536{ 537 struct scatterlist *sg; 538 u8 *src; 539 int r = 0; 540 541 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 542 sg = crypt_get_sg_data(cc, dmreq->sg_in); 543 src = kmap_local_page(sg_page(sg)); 544 r = crypt_iv_lmk_one(cc, iv, dmreq, src + sg->offset); 545 kunmap_local(src); 546 } else 547 memset(iv, 0, cc->iv_size); 548 549 return r; 550} 551 552static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv, 553 struct dm_crypt_request *dmreq) 554{ 555 struct scatterlist *sg; 556 u8 *dst; 557 int r; 558 559 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) 560 return 0; 561 562 sg = crypt_get_sg_data(cc, dmreq->sg_out); 563 dst = kmap_local_page(sg_page(sg)); 564 r = crypt_iv_lmk_one(cc, iv, dmreq, dst + sg->offset); 565 566 /* Tweak the first block of plaintext sector */ 567 if (!r) 568 crypto_xor(dst + sg->offset, iv, cc->iv_size); 569 570 kunmap_local(dst); 571 return r; 572} 573 574static void crypt_iv_tcw_dtr(struct crypt_config *cc) 575{ 576 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 577 578 kfree_sensitive(tcw->iv_seed); 579 tcw->iv_seed = NULL; 580 kfree_sensitive(tcw->whitening); 581 tcw->whitening = NULL; 582 583 if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm)) 584 crypto_free_shash(tcw->crc32_tfm); 585 tcw->crc32_tfm = NULL; 586} 587 588static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti, 589 const char *opts) 590{ 591 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 592 593 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 594 ti->error = "Unsupported sector size for TCW"; 595 return -EINVAL; 596 } 597 598 if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) { 599 ti->error = "Wrong key size for TCW"; 600 return -EINVAL; 601 } 602 603 tcw->crc32_tfm = crypto_alloc_shash("crc32", 0, 604 CRYPTO_ALG_ALLOCATES_MEMORY); 605 if (IS_ERR(tcw->crc32_tfm)) { 606 ti->error = "Error initializing CRC32 in TCW"; 607 return PTR_ERR(tcw->crc32_tfm); 608 } 609 610 tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL); 611 tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL); 612 if (!tcw->iv_seed || !tcw->whitening) { 613 crypt_iv_tcw_dtr(cc); 614 ti->error = "Error allocating seed storage in TCW"; 615 return -ENOMEM; 616 } 617 618 return 0; 619} 620 621static int crypt_iv_tcw_init(struct crypt_config *cc) 622{ 623 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 624 int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE; 625 626 memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size); 627 memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size], 628 TCW_WHITENING_SIZE); 629 630 return 0; 631} 632 633static int crypt_iv_tcw_wipe(struct crypt_config *cc) 634{ 635 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 636 637 memset(tcw->iv_seed, 0, cc->iv_size); 638 memset(tcw->whitening, 0, TCW_WHITENING_SIZE); 639 640 return 0; 641} 642 643static int crypt_iv_tcw_whitening(struct crypt_config *cc, 644 struct dm_crypt_request *dmreq, 645 u8 *data) 646{ 647 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 648 __le64 sector = cpu_to_le64(dmreq->iv_sector); 649 u8 buf[TCW_WHITENING_SIZE]; 650 SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm); 651 int i, r; 652 653 /* xor whitening with sector number */ 654 crypto_xor_cpy(buf, tcw->whitening, (u8 *)§or, 8); 655 crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)§or, 8); 656 657 /* calculate crc32 for every 32bit part and xor it */ 658 desc->tfm = tcw->crc32_tfm; 659 for (i = 0; i < 4; i++) { 660 r = crypto_shash_digest(desc, &buf[i * 4], 4, &buf[i * 4]); 661 if (r) 662 goto out; 663 } 664 crypto_xor(&buf[0], &buf[12], 4); 665 crypto_xor(&buf[4], &buf[8], 4); 666 667 /* apply whitening (8 bytes) to whole sector */ 668 for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++) 669 crypto_xor(data + i * 8, buf, 8); 670out: 671 memzero_explicit(buf, sizeof(buf)); 672 return r; 673} 674 675static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv, 676 struct dm_crypt_request *dmreq) 677{ 678 struct scatterlist *sg; 679 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 680 __le64 sector = cpu_to_le64(dmreq->iv_sector); 681 u8 *src; 682 int r = 0; 683 684 /* Remove whitening from ciphertext */ 685 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 686 sg = crypt_get_sg_data(cc, dmreq->sg_in); 687 src = kmap_local_page(sg_page(sg)); 688 r = crypt_iv_tcw_whitening(cc, dmreq, src + sg->offset); 689 kunmap_local(src); 690 } 691 692 /* Calculate IV */ 693 crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)§or, 8); 694 if (cc->iv_size > 8) 695 crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)§or, 696 cc->iv_size - 8); 697 698 return r; 699} 700 701static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv, 702 struct dm_crypt_request *dmreq) 703{ 704 struct scatterlist *sg; 705 u8 *dst; 706 int r; 707 708 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 709 return 0; 710 711 /* Apply whitening on ciphertext */ 712 sg = crypt_get_sg_data(cc, dmreq->sg_out); 713 dst = kmap_local_page(sg_page(sg)); 714 r = crypt_iv_tcw_whitening(cc, dmreq, dst + sg->offset); 715 kunmap_local(dst); 716 717 return r; 718} 719 720static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv, 721 struct dm_crypt_request *dmreq) 722{ 723 /* Used only for writes, there must be an additional space to store IV */ 724 get_random_bytes(iv, cc->iv_size); 725 return 0; 726} 727 728static int crypt_iv_eboiv_ctr(struct crypt_config *cc, struct dm_target *ti, 729 const char *opts) 730{ 731 if (crypt_integrity_aead(cc)) { 732 ti->error = "AEAD transforms not supported for EBOIV"; 733 return -EINVAL; 734 } 735 736 if (crypto_skcipher_blocksize(any_tfm(cc)) != cc->iv_size) { 737 ti->error = "Block size of EBOIV cipher does not match IV size of block cipher"; 738 return -EINVAL; 739 } 740 741 return 0; 742} 743 744static int crypt_iv_eboiv_gen(struct crypt_config *cc, u8 *iv, 745 struct dm_crypt_request *dmreq) 746{ 747 struct crypto_skcipher *tfm = any_tfm(cc); 748 struct skcipher_request *req; 749 struct scatterlist src, dst; 750 DECLARE_CRYPTO_WAIT(wait); 751 unsigned int reqsize; 752 int err; 753 u8 *buf; 754 755 reqsize = sizeof(*req) + crypto_skcipher_reqsize(tfm); 756 reqsize = ALIGN(reqsize, __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 778static 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 786static 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 806static 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 816static 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 826static 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 857static 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 888static 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 919static 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 950static 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); 1016out: 1017 kfree_sensitive(ks); 1018 kfree_sensitive(es); 1019 skcipher_request_free(req); 1020 return r; 1021} 1022 1023static 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 1037static 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 1046static 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 1054static 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 1063static const struct crypt_iv_operations crypt_iv_plain_ops = { 1064 .generator = crypt_iv_plain_gen 1065}; 1066 1067static const struct crypt_iv_operations crypt_iv_plain64_ops = { 1068 .generator = crypt_iv_plain64_gen 1069}; 1070 1071static const struct crypt_iv_operations crypt_iv_plain64be_ops = { 1072 .generator = crypt_iv_plain64be_gen 1073}; 1074 1075static const struct crypt_iv_operations crypt_iv_essiv_ops = { 1076 .generator = crypt_iv_essiv_gen 1077}; 1078 1079static 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 1085static const struct crypt_iv_operations crypt_iv_null_ops = { 1086 .generator = crypt_iv_null_gen 1087}; 1088 1089static 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 1098static 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 1107static const struct crypt_iv_operations crypt_iv_random_ops = { 1108 .generator = crypt_iv_random_gen 1109}; 1110 1111static const struct crypt_iv_operations crypt_iv_eboiv_ops = { 1112 .ctr = crypt_iv_eboiv_ctr, 1113 .generator = crypt_iv_eboiv_gen 1114}; 1115 1116static 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 */ 1128static bool crypt_integrity_aead(struct crypt_config *cc) 1129{ 1130 return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 1131} 1132 1133static 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 */ 1139static 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 1148static 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 1173static 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 1220static 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 1235static 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 1241static void *req_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq) 1242{ 1243 return (void *)((char *)dmreq - cc->dmreq_start); 1244} 1245 1246static 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 1257static 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 1263static __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 1271static 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 1280static 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 1290static 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 1296static 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 ctx->aead_failed = true; 1381 if (ctx->aead_recheck) { 1382 DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu", 1383 ctx->bio_in->bi_bdev, s); 1384 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead", 1385 ctx->bio_in, s, 0); 1386 } 1387 } 1388 1389 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1390 r = cc->iv_gen_ops->post(cc, org_iv, dmreq); 1391 1392 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1393 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1394 1395 return r; 1396} 1397 1398static int crypt_convert_block_skcipher(struct crypt_config *cc, 1399 struct convert_context *ctx, 1400 struct skcipher_request *req, 1401 unsigned int tag_offset) 1402{ 1403 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1404 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1405 struct scatterlist *sg_in, *sg_out; 1406 struct dm_crypt_request *dmreq; 1407 u8 *iv, *org_iv, *tag_iv; 1408 __le64 *sector; 1409 int r = 0; 1410 1411 /* Reject unexpected unaligned bio. */ 1412 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1413 return -EIO; 1414 1415 dmreq = dmreq_of_req(cc, req); 1416 dmreq->iv_sector = ctx->cc_sector; 1417 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1418 dmreq->iv_sector >>= cc->sector_shift; 1419 dmreq->ctx = ctx; 1420 1421 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1422 1423 iv = iv_of_dmreq(cc, dmreq); 1424 org_iv = org_iv_of_dmreq(cc, dmreq); 1425 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1426 1427 sector = org_sector_of_dmreq(cc, dmreq); 1428 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1429 1430 /* For skcipher we use only the first sg item */ 1431 sg_in = &dmreq->sg_in[0]; 1432 sg_out = &dmreq->sg_out[0]; 1433 1434 sg_init_table(sg_in, 1); 1435 sg_set_page(sg_in, bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1436 1437 sg_init_table(sg_out, 1); 1438 sg_set_page(sg_out, bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1439 1440 if (cc->iv_gen_ops) { 1441 /* For READs use IV stored in integrity metadata */ 1442 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1443 memcpy(org_iv, tag_iv, cc->integrity_iv_size); 1444 } else { 1445 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1446 if (r < 0) 1447 return r; 1448 /* Data can be already preprocessed in generator */ 1449 if (test_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags)) 1450 sg_in = sg_out; 1451 /* Store generated IV in integrity metadata */ 1452 if (cc->integrity_iv_size) 1453 memcpy(tag_iv, org_iv, cc->integrity_iv_size); 1454 } 1455 /* Working copy of IV, to be modified in crypto API */ 1456 memcpy(iv, org_iv, cc->iv_size); 1457 } 1458 1459 skcipher_request_set_crypt(req, sg_in, sg_out, cc->sector_size, iv); 1460 1461 if (bio_data_dir(ctx->bio_in) == WRITE) 1462 r = crypto_skcipher_encrypt(req); 1463 else 1464 r = crypto_skcipher_decrypt(req); 1465 1466 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1467 r = cc->iv_gen_ops->post(cc, org_iv, dmreq); 1468 1469 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1470 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1471 1472 return r; 1473} 1474 1475static void kcryptd_async_done(void *async_req, int error); 1476 1477static int crypt_alloc_req_skcipher(struct crypt_config *cc, 1478 struct convert_context *ctx) 1479{ 1480 unsigned int key_index = ctx->cc_sector & (cc->tfms_count - 1); 1481 1482 if (!ctx->r.req) { 1483 ctx->r.req = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1484 if (!ctx->r.req) 1485 return -ENOMEM; 1486 } 1487 1488 skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]); 1489 1490 /* 1491 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1492 * requests if driver request queue is full. 1493 */ 1494 skcipher_request_set_callback(ctx->r.req, 1495 CRYPTO_TFM_REQ_MAY_BACKLOG, 1496 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req)); 1497 1498 return 0; 1499} 1500 1501static int crypt_alloc_req_aead(struct crypt_config *cc, 1502 struct convert_context *ctx) 1503{ 1504 if (!ctx->r.req_aead) { 1505 ctx->r.req_aead = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1506 if (!ctx->r.req_aead) 1507 return -ENOMEM; 1508 } 1509 1510 aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]); 1511 1512 /* 1513 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1514 * requests if driver request queue is full. 1515 */ 1516 aead_request_set_callback(ctx->r.req_aead, 1517 CRYPTO_TFM_REQ_MAY_BACKLOG, 1518 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead)); 1519 1520 return 0; 1521} 1522 1523static int crypt_alloc_req(struct crypt_config *cc, 1524 struct convert_context *ctx) 1525{ 1526 if (crypt_integrity_aead(cc)) 1527 return crypt_alloc_req_aead(cc, ctx); 1528 else 1529 return crypt_alloc_req_skcipher(cc, ctx); 1530} 1531 1532static void crypt_free_req_skcipher(struct crypt_config *cc, 1533 struct skcipher_request *req, struct bio *base_bio) 1534{ 1535 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1536 1537 if ((struct skcipher_request *)(io + 1) != req) 1538 mempool_free(req, &cc->req_pool); 1539} 1540 1541static void crypt_free_req_aead(struct crypt_config *cc, 1542 struct aead_request *req, struct bio *base_bio) 1543{ 1544 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1545 1546 if ((struct aead_request *)(io + 1) != req) 1547 mempool_free(req, &cc->req_pool); 1548} 1549 1550static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio) 1551{ 1552 if (crypt_integrity_aead(cc)) 1553 crypt_free_req_aead(cc, req, base_bio); 1554 else 1555 crypt_free_req_skcipher(cc, req, base_bio); 1556} 1557 1558/* 1559 * Encrypt / decrypt data from one bio to another one (can be the same one) 1560 */ 1561static blk_status_t crypt_convert(struct crypt_config *cc, 1562 struct convert_context *ctx, bool atomic, bool reset_pending) 1563{ 1564 unsigned int tag_offset = 0; 1565 unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT; 1566 int r; 1567 1568 /* 1569 * if reset_pending is set we are dealing with the bio for the first time, 1570 * else we're continuing to work on the previous bio, so don't mess with 1571 * the cc_pending counter 1572 */ 1573 if (reset_pending) 1574 atomic_set(&ctx->cc_pending, 1); 1575 1576 while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) { 1577 1578 r = crypt_alloc_req(cc, ctx); 1579 if (r) { 1580 complete(&ctx->restart); 1581 return BLK_STS_DEV_RESOURCE; 1582 } 1583 1584 atomic_inc(&ctx->cc_pending); 1585 1586 if (crypt_integrity_aead(cc)) 1587 r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, tag_offset); 1588 else 1589 r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, tag_offset); 1590 1591 switch (r) { 1592 /* 1593 * The request was queued by a crypto driver 1594 * but the driver request queue is full, let's wait. 1595 */ 1596 case -EBUSY: 1597 if (in_interrupt()) { 1598 if (try_wait_for_completion(&ctx->restart)) { 1599 /* 1600 * we don't have to block to wait for completion, 1601 * so proceed 1602 */ 1603 } else { 1604 /* 1605 * we can't wait for completion without blocking 1606 * exit and continue processing in a workqueue 1607 */ 1608 ctx->r.req = NULL; 1609 ctx->cc_sector += sector_step; 1610 tag_offset++; 1611 return BLK_STS_DEV_RESOURCE; 1612 } 1613 } else { 1614 wait_for_completion(&ctx->restart); 1615 } 1616 reinit_completion(&ctx->restart); 1617 fallthrough; 1618 /* 1619 * The request is queued and processed asynchronously, 1620 * completion function kcryptd_async_done() will be called. 1621 */ 1622 case -EINPROGRESS: 1623 ctx->r.req = NULL; 1624 ctx->cc_sector += sector_step; 1625 tag_offset++; 1626 continue; 1627 /* 1628 * The request was already processed (synchronously). 1629 */ 1630 case 0: 1631 atomic_dec(&ctx->cc_pending); 1632 ctx->cc_sector += sector_step; 1633 tag_offset++; 1634 if (!atomic) 1635 cond_resched(); 1636 continue; 1637 /* 1638 * There was a data integrity error. 1639 */ 1640 case -EBADMSG: 1641 atomic_dec(&ctx->cc_pending); 1642 return BLK_STS_PROTECTION; 1643 /* 1644 * There was an error while processing the request. 1645 */ 1646 default: 1647 atomic_dec(&ctx->cc_pending); 1648 return BLK_STS_IOERR; 1649 } 1650 } 1651 1652 return 0; 1653} 1654 1655static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone); 1656 1657/* 1658 * Generate a new unfragmented bio with the given size 1659 * This should never violate the device limitations (but if it did then block 1660 * core should split the bio as needed). 1661 * 1662 * This function may be called concurrently. If we allocate from the mempool 1663 * concurrently, there is a possibility of deadlock. For example, if we have 1664 * mempool of 256 pages, two processes, each wanting 256, pages allocate from 1665 * the mempool concurrently, it may deadlock in a situation where both processes 1666 * have allocated 128 pages and the mempool is exhausted. 1667 * 1668 * In order to avoid this scenario we allocate the pages under a mutex. 1669 * 1670 * In order to not degrade performance with excessive locking, we try 1671 * non-blocking allocations without a mutex first but on failure we fallback 1672 * to blocking allocations with a mutex. 1673 * 1674 * In order to reduce allocation overhead, we try to allocate compound pages in 1675 * the first pass. If they are not available, we fall back to the mempool. 1676 */ 1677static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned int size) 1678{ 1679 struct crypt_config *cc = io->cc; 1680 struct bio *clone; 1681 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; 1682 gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM; 1683 unsigned int remaining_size; 1684 unsigned int order = MAX_PAGE_ORDER; 1685 1686retry: 1687 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1688 mutex_lock(&cc->bio_alloc_lock); 1689 1690 clone = bio_alloc_bioset(cc->dev->bdev, nr_iovecs, io->base_bio->bi_opf, 1691 GFP_NOIO, &cc->bs); 1692 clone->bi_private = io; 1693 clone->bi_end_io = crypt_endio; 1694 clone->bi_ioprio = io->base_bio->bi_ioprio; 1695 1696 remaining_size = size; 1697 1698 while (remaining_size) { 1699 struct page *pages; 1700 unsigned size_to_add; 1701 unsigned remaining_order = __fls((remaining_size + PAGE_SIZE - 1) >> PAGE_SHIFT); 1702 order = min(order, remaining_order); 1703 1704 while (order > 0) { 1705 if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) + 1706 (1 << order) > dm_crypt_pages_per_client)) 1707 goto decrease_order; 1708 pages = alloc_pages(gfp_mask 1709 | __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN | __GFP_COMP, 1710 order); 1711 if (likely(pages != NULL)) { 1712 percpu_counter_add(&cc->n_allocated_pages, 1 << order); 1713 goto have_pages; 1714 } 1715decrease_order: 1716 order--; 1717 } 1718 1719 pages = mempool_alloc(&cc->page_pool, gfp_mask); 1720 if (!pages) { 1721 crypt_free_buffer_pages(cc, clone); 1722 bio_put(clone); 1723 gfp_mask |= __GFP_DIRECT_RECLAIM; 1724 order = 0; 1725 goto retry; 1726 } 1727 1728have_pages: 1729 size_to_add = min((unsigned)PAGE_SIZE << order, remaining_size); 1730 __bio_add_page(clone, pages, size_to_add, 0); 1731 remaining_size -= size_to_add; 1732 } 1733 1734 /* Allocate space for integrity tags */ 1735 if (dm_crypt_integrity_io_alloc(io, clone)) { 1736 crypt_free_buffer_pages(cc, clone); 1737 bio_put(clone); 1738 clone = NULL; 1739 } 1740 1741 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1742 mutex_unlock(&cc->bio_alloc_lock); 1743 1744 return clone; 1745} 1746 1747static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) 1748{ 1749 struct folio_iter fi; 1750 1751 if (clone->bi_vcnt > 0) { /* bio_for_each_folio_all crashes with an empty bio */ 1752 bio_for_each_folio_all(fi, clone) { 1753 if (folio_test_large(fi.folio)) { 1754 percpu_counter_sub(&cc->n_allocated_pages, 1755 1 << folio_order(fi.folio)); 1756 folio_put(fi.folio); 1757 } else { 1758 mempool_free(&fi.folio->page, &cc->page_pool); 1759 } 1760 } 1761 } 1762} 1763 1764static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc, 1765 struct bio *bio, sector_t sector) 1766{ 1767 io->cc = cc; 1768 io->base_bio = bio; 1769 io->sector = sector; 1770 io->error = 0; 1771 io->ctx.aead_recheck = false; 1772 io->ctx.aead_failed = false; 1773 io->ctx.r.req = NULL; 1774 io->integrity_metadata = NULL; 1775 io->integrity_metadata_from_pool = false; 1776 atomic_set(&io->io_pending, 0); 1777} 1778 1779static void crypt_inc_pending(struct dm_crypt_io *io) 1780{ 1781 atomic_inc(&io->io_pending); 1782} 1783 1784static void kcryptd_queue_read(struct dm_crypt_io *io); 1785 1786/* 1787 * One of the bios was finished. Check for completion of 1788 * the whole request and correctly clean up the buffer. 1789 */ 1790static void crypt_dec_pending(struct dm_crypt_io *io) 1791{ 1792 struct crypt_config *cc = io->cc; 1793 struct bio *base_bio = io->base_bio; 1794 blk_status_t error = io->error; 1795 1796 if (!atomic_dec_and_test(&io->io_pending)) 1797 return; 1798 1799 if (likely(!io->ctx.aead_recheck) && unlikely(io->ctx.aead_failed) && 1800 cc->on_disk_tag_size && bio_data_dir(base_bio) == READ) { 1801 io->ctx.aead_recheck = true; 1802 io->ctx.aead_failed = false; 1803 io->error = 0; 1804 kcryptd_queue_read(io); 1805 return; 1806 } 1807 1808 if (io->ctx.r.req) 1809 crypt_free_req(cc, io->ctx.r.req, base_bio); 1810 1811 if (unlikely(io->integrity_metadata_from_pool)) 1812 mempool_free(io->integrity_metadata, &io->cc->tag_pool); 1813 else 1814 kfree(io->integrity_metadata); 1815 1816 base_bio->bi_status = error; 1817 1818 bio_endio(base_bio); 1819} 1820 1821/* 1822 * kcryptd/kcryptd_io: 1823 * 1824 * Needed because it would be very unwise to do decryption in an 1825 * interrupt context. 1826 * 1827 * kcryptd performs the actual encryption or decryption. 1828 * 1829 * kcryptd_io performs the IO submission. 1830 * 1831 * They must be separated as otherwise the final stages could be 1832 * starved by new requests which can block in the first stages due 1833 * to memory allocation. 1834 * 1835 * The work is done per CPU global for all dm-crypt instances. 1836 * They should not depend on each other and do not block. 1837 */ 1838static void crypt_endio(struct bio *clone) 1839{ 1840 struct dm_crypt_io *io = clone->bi_private; 1841 struct crypt_config *cc = io->cc; 1842 unsigned int rw = bio_data_dir(clone); 1843 blk_status_t error = clone->bi_status; 1844 1845 if (io->ctx.aead_recheck && !error) { 1846 kcryptd_queue_crypt(io); 1847 return; 1848 } 1849 1850 /* 1851 * free the processed pages 1852 */ 1853 if (rw == WRITE || io->ctx.aead_recheck) 1854 crypt_free_buffer_pages(cc, clone); 1855 1856 bio_put(clone); 1857 1858 if (rw == READ && !error) { 1859 kcryptd_queue_crypt(io); 1860 return; 1861 } 1862 1863 if (unlikely(error)) 1864 io->error = error; 1865 1866 crypt_dec_pending(io); 1867} 1868 1869#define CRYPT_MAP_READ_GFP GFP_NOWAIT 1870 1871static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp) 1872{ 1873 struct crypt_config *cc = io->cc; 1874 struct bio *clone; 1875 1876 if (io->ctx.aead_recheck) { 1877 if (!(gfp & __GFP_DIRECT_RECLAIM)) 1878 return 1; 1879 crypt_inc_pending(io); 1880 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size); 1881 if (unlikely(!clone)) { 1882 crypt_dec_pending(io); 1883 return 1; 1884 } 1885 clone->bi_iter.bi_sector = cc->start + io->sector; 1886 crypt_convert_init(cc, &io->ctx, clone, clone, io->sector); 1887 io->saved_bi_iter = clone->bi_iter; 1888 dm_submit_bio_remap(io->base_bio, clone); 1889 return 0; 1890 } 1891 1892 /* 1893 * We need the original biovec array in order to decrypt the whole bio 1894 * data *afterwards* -- thanks to immutable biovecs we don't need to 1895 * worry about the block layer modifying the biovec array; so leverage 1896 * bio_alloc_clone(). 1897 */ 1898 clone = bio_alloc_clone(cc->dev->bdev, io->base_bio, gfp, &cc->bs); 1899 if (!clone) 1900 return 1; 1901 clone->bi_private = io; 1902 clone->bi_end_io = crypt_endio; 1903 1904 crypt_inc_pending(io); 1905 1906 clone->bi_iter.bi_sector = cc->start + io->sector; 1907 1908 if (dm_crypt_integrity_io_alloc(io, clone)) { 1909 crypt_dec_pending(io); 1910 bio_put(clone); 1911 return 1; 1912 } 1913 1914 dm_submit_bio_remap(io->base_bio, clone); 1915 return 0; 1916} 1917 1918static void kcryptd_io_read_work(struct work_struct *work) 1919{ 1920 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 1921 1922 crypt_inc_pending(io); 1923 if (kcryptd_io_read(io, GFP_NOIO)) 1924 io->error = BLK_STS_RESOURCE; 1925 crypt_dec_pending(io); 1926} 1927 1928static void kcryptd_queue_read(struct dm_crypt_io *io) 1929{ 1930 struct crypt_config *cc = io->cc; 1931 1932 INIT_WORK(&io->work, kcryptd_io_read_work); 1933 queue_work(cc->io_queue, &io->work); 1934} 1935 1936static void kcryptd_io_write(struct dm_crypt_io *io) 1937{ 1938 struct bio *clone = io->ctx.bio_out; 1939 1940 dm_submit_bio_remap(io->base_bio, clone); 1941} 1942 1943#define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node) 1944 1945static int dmcrypt_write(void *data) 1946{ 1947 struct crypt_config *cc = data; 1948 struct dm_crypt_io *io; 1949 1950 while (1) { 1951 struct rb_root write_tree; 1952 struct blk_plug plug; 1953 1954 spin_lock_irq(&cc->write_thread_lock); 1955continue_locked: 1956 1957 if (!RB_EMPTY_ROOT(&cc->write_tree)) 1958 goto pop_from_list; 1959 1960 set_current_state(TASK_INTERRUPTIBLE); 1961 1962 spin_unlock_irq(&cc->write_thread_lock); 1963 1964 if (unlikely(kthread_should_stop())) { 1965 set_current_state(TASK_RUNNING); 1966 break; 1967 } 1968 1969 schedule(); 1970 1971 spin_lock_irq(&cc->write_thread_lock); 1972 goto continue_locked; 1973 1974pop_from_list: 1975 write_tree = cc->write_tree; 1976 cc->write_tree = RB_ROOT; 1977 spin_unlock_irq(&cc->write_thread_lock); 1978 1979 BUG_ON(rb_parent(write_tree.rb_node)); 1980 1981 /* 1982 * Note: we cannot walk the tree here with rb_next because 1983 * the structures may be freed when kcryptd_io_write is called. 1984 */ 1985 blk_start_plug(&plug); 1986 do { 1987 io = crypt_io_from_node(rb_first(&write_tree)); 1988 rb_erase(&io->rb_node, &write_tree); 1989 kcryptd_io_write(io); 1990 cond_resched(); 1991 } while (!RB_EMPTY_ROOT(&write_tree)); 1992 blk_finish_plug(&plug); 1993 } 1994 return 0; 1995} 1996 1997static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async) 1998{ 1999 struct bio *clone = io->ctx.bio_out; 2000 struct crypt_config *cc = io->cc; 2001 unsigned long flags; 2002 sector_t sector; 2003 struct rb_node **rbp, *parent; 2004 2005 if (unlikely(io->error)) { 2006 crypt_free_buffer_pages(cc, clone); 2007 bio_put(clone); 2008 crypt_dec_pending(io); 2009 return; 2010 } 2011 2012 /* crypt_convert should have filled the clone bio */ 2013 BUG_ON(io->ctx.iter_out.bi_size); 2014 2015 clone->bi_iter.bi_sector = cc->start + io->sector; 2016 2017 if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) || 2018 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) { 2019 dm_submit_bio_remap(io->base_bio, clone); 2020 return; 2021 } 2022 2023 spin_lock_irqsave(&cc->write_thread_lock, flags); 2024 if (RB_EMPTY_ROOT(&cc->write_tree)) 2025 wake_up_process(cc->write_thread); 2026 rbp = &cc->write_tree.rb_node; 2027 parent = NULL; 2028 sector = io->sector; 2029 while (*rbp) { 2030 parent = *rbp; 2031 if (sector < crypt_io_from_node(parent)->sector) 2032 rbp = &(*rbp)->rb_left; 2033 else 2034 rbp = &(*rbp)->rb_right; 2035 } 2036 rb_link_node(&io->rb_node, parent, rbp); 2037 rb_insert_color(&io->rb_node, &cc->write_tree); 2038 spin_unlock_irqrestore(&cc->write_thread_lock, flags); 2039} 2040 2041static bool kcryptd_crypt_write_inline(struct crypt_config *cc, 2042 struct convert_context *ctx) 2043 2044{ 2045 if (!test_bit(DM_CRYPT_WRITE_INLINE, &cc->flags)) 2046 return false; 2047 2048 /* 2049 * Note: zone append writes (REQ_OP_ZONE_APPEND) do not have ordering 2050 * constraints so they do not need to be issued inline by 2051 * kcryptd_crypt_write_convert(). 2052 */ 2053 switch (bio_op(ctx->bio_in)) { 2054 case REQ_OP_WRITE: 2055 case REQ_OP_WRITE_ZEROES: 2056 return true; 2057 default: 2058 return false; 2059 } 2060} 2061 2062static void kcryptd_crypt_write_continue(struct work_struct *work) 2063{ 2064 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2065 struct crypt_config *cc = io->cc; 2066 struct convert_context *ctx = &io->ctx; 2067 int crypt_finished; 2068 sector_t sector = io->sector; 2069 blk_status_t r; 2070 2071 wait_for_completion(&ctx->restart); 2072 reinit_completion(&ctx->restart); 2073 2074 r = crypt_convert(cc, &io->ctx, true, false); 2075 if (r) 2076 io->error = r; 2077 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2078 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2079 /* Wait for completion signaled by kcryptd_async_done() */ 2080 wait_for_completion(&ctx->restart); 2081 crypt_finished = 1; 2082 } 2083 2084 /* Encryption was already finished, submit io now */ 2085 if (crypt_finished) { 2086 kcryptd_crypt_write_io_submit(io, 0); 2087 io->sector = sector; 2088 } 2089 2090 crypt_dec_pending(io); 2091} 2092 2093static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) 2094{ 2095 struct crypt_config *cc = io->cc; 2096 struct convert_context *ctx = &io->ctx; 2097 struct bio *clone; 2098 int crypt_finished; 2099 sector_t sector = io->sector; 2100 blk_status_t r; 2101 2102 /* 2103 * Prevent io from disappearing until this function completes. 2104 */ 2105 crypt_inc_pending(io); 2106 crypt_convert_init(cc, ctx, NULL, io->base_bio, sector); 2107 2108 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size); 2109 if (unlikely(!clone)) { 2110 io->error = BLK_STS_IOERR; 2111 goto dec; 2112 } 2113 2114 io->ctx.bio_out = clone; 2115 io->ctx.iter_out = clone->bi_iter; 2116 2117 if (crypt_integrity_aead(cc)) { 2118 bio_copy_data(clone, io->base_bio); 2119 io->ctx.bio_in = clone; 2120 io->ctx.iter_in = clone->bi_iter; 2121 } 2122 2123 sector += bio_sectors(clone); 2124 2125 crypt_inc_pending(io); 2126 r = crypt_convert(cc, ctx, 2127 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags), true); 2128 /* 2129 * Crypto API backlogged the request, because its queue was full 2130 * and we're in softirq context, so continue from a workqueue 2131 * (TODO: is it actually possible to be in softirq in the write path?) 2132 */ 2133 if (r == BLK_STS_DEV_RESOURCE) { 2134 INIT_WORK(&io->work, kcryptd_crypt_write_continue); 2135 queue_work(cc->crypt_queue, &io->work); 2136 return; 2137 } 2138 if (r) 2139 io->error = r; 2140 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2141 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2142 /* Wait for completion signaled by kcryptd_async_done() */ 2143 wait_for_completion(&ctx->restart); 2144 crypt_finished = 1; 2145 } 2146 2147 /* Encryption was already finished, submit io now */ 2148 if (crypt_finished) { 2149 kcryptd_crypt_write_io_submit(io, 0); 2150 io->sector = sector; 2151 } 2152 2153dec: 2154 crypt_dec_pending(io); 2155} 2156 2157static void kcryptd_crypt_read_done(struct dm_crypt_io *io) 2158{ 2159 if (io->ctx.aead_recheck) { 2160 if (!io->error) { 2161 io->ctx.bio_in->bi_iter = io->saved_bi_iter; 2162 bio_copy_data(io->base_bio, io->ctx.bio_in); 2163 } 2164 crypt_free_buffer_pages(io->cc, io->ctx.bio_in); 2165 bio_put(io->ctx.bio_in); 2166 } 2167 crypt_dec_pending(io); 2168} 2169 2170static void kcryptd_crypt_read_continue(struct work_struct *work) 2171{ 2172 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2173 struct crypt_config *cc = io->cc; 2174 blk_status_t r; 2175 2176 wait_for_completion(&io->ctx.restart); 2177 reinit_completion(&io->ctx.restart); 2178 2179 r = crypt_convert(cc, &io->ctx, true, false); 2180 if (r) 2181 io->error = r; 2182 2183 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2184 kcryptd_crypt_read_done(io); 2185 2186 crypt_dec_pending(io); 2187} 2188 2189static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) 2190{ 2191 struct crypt_config *cc = io->cc; 2192 blk_status_t r; 2193 2194 crypt_inc_pending(io); 2195 2196 if (io->ctx.aead_recheck) { 2197 io->ctx.cc_sector = io->sector + cc->iv_offset; 2198 r = crypt_convert(cc, &io->ctx, 2199 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true); 2200 } else { 2201 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, 2202 io->sector); 2203 2204 r = crypt_convert(cc, &io->ctx, 2205 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true); 2206 } 2207 /* 2208 * Crypto API backlogged the request, because its queue was full 2209 * and we're in softirq context, so continue from a workqueue 2210 */ 2211 if (r == BLK_STS_DEV_RESOURCE) { 2212 INIT_WORK(&io->work, kcryptd_crypt_read_continue); 2213 queue_work(cc->crypt_queue, &io->work); 2214 return; 2215 } 2216 if (r) 2217 io->error = r; 2218 2219 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2220 kcryptd_crypt_read_done(io); 2221 2222 crypt_dec_pending(io); 2223} 2224 2225static void kcryptd_async_done(void *data, int error) 2226{ 2227 struct dm_crypt_request *dmreq = data; 2228 struct convert_context *ctx = dmreq->ctx; 2229 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 2230 struct crypt_config *cc = io->cc; 2231 2232 /* 2233 * A request from crypto driver backlog is going to be processed now, 2234 * finish the completion and continue in crypt_convert(). 2235 * (Callback will be called for the second time for this request.) 2236 */ 2237 if (error == -EINPROGRESS) { 2238 complete(&ctx->restart); 2239 return; 2240 } 2241 2242 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post) 2243 error = cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq); 2244 2245 if (error == -EBADMSG) { 2246 sector_t s = le64_to_cpu(*org_sector_of_dmreq(cc, dmreq)); 2247 2248 ctx->aead_failed = true; 2249 if (ctx->aead_recheck) { 2250 DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu", 2251 ctx->bio_in->bi_bdev, s); 2252 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead", 2253 ctx->bio_in, s, 0); 2254 } 2255 io->error = BLK_STS_PROTECTION; 2256 } else if (error < 0) 2257 io->error = BLK_STS_IOERR; 2258 2259 crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio); 2260 2261 if (!atomic_dec_and_test(&ctx->cc_pending)) 2262 return; 2263 2264 /* 2265 * The request is fully completed: for inline writes, let 2266 * kcryptd_crypt_write_convert() do the IO submission. 2267 */ 2268 if (bio_data_dir(io->base_bio) == READ) { 2269 kcryptd_crypt_read_done(io); 2270 return; 2271 } 2272 2273 if (kcryptd_crypt_write_inline(cc, ctx)) { 2274 complete(&ctx->restart); 2275 return; 2276 } 2277 2278 kcryptd_crypt_write_io_submit(io, 1); 2279} 2280 2281static void kcryptd_crypt(struct work_struct *work) 2282{ 2283 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2284 2285 if (bio_data_dir(io->base_bio) == READ) 2286 kcryptd_crypt_read_convert(io); 2287 else 2288 kcryptd_crypt_write_convert(io); 2289} 2290 2291static void kcryptd_queue_crypt(struct dm_crypt_io *io) 2292{ 2293 struct crypt_config *cc = io->cc; 2294 2295 if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) || 2296 (bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) { 2297 /* 2298 * in_hardirq(): Crypto API's skcipher_walk_first() refuses to work in hard IRQ context. 2299 * irqs_disabled(): the kernel may run some IO completion from the idle thread, but 2300 * it is being executed with irqs disabled. 2301 */ 2302 if (in_hardirq() || irqs_disabled()) { 2303 INIT_WORK(&io->work, kcryptd_crypt); 2304 queue_work(system_bh_wq, &io->work); 2305 return; 2306 } else { 2307 kcryptd_crypt(&io->work); 2308 return; 2309 } 2310 } 2311 2312 INIT_WORK(&io->work, kcryptd_crypt); 2313 queue_work(cc->crypt_queue, &io->work); 2314} 2315 2316static void crypt_free_tfms_aead(struct crypt_config *cc) 2317{ 2318 if (!cc->cipher_tfm.tfms_aead) 2319 return; 2320 2321 if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2322 crypto_free_aead(cc->cipher_tfm.tfms_aead[0]); 2323 cc->cipher_tfm.tfms_aead[0] = NULL; 2324 } 2325 2326 kfree(cc->cipher_tfm.tfms_aead); 2327 cc->cipher_tfm.tfms_aead = NULL; 2328} 2329 2330static void crypt_free_tfms_skcipher(struct crypt_config *cc) 2331{ 2332 unsigned int i; 2333 2334 if (!cc->cipher_tfm.tfms) 2335 return; 2336 2337 for (i = 0; i < cc->tfms_count; i++) 2338 if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) { 2339 crypto_free_skcipher(cc->cipher_tfm.tfms[i]); 2340 cc->cipher_tfm.tfms[i] = NULL; 2341 } 2342 2343 kfree(cc->cipher_tfm.tfms); 2344 cc->cipher_tfm.tfms = NULL; 2345} 2346 2347static void crypt_free_tfms(struct crypt_config *cc) 2348{ 2349 if (crypt_integrity_aead(cc)) 2350 crypt_free_tfms_aead(cc); 2351 else 2352 crypt_free_tfms_skcipher(cc); 2353} 2354 2355static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode) 2356{ 2357 unsigned int i; 2358 int err; 2359 2360 cc->cipher_tfm.tfms = kcalloc(cc->tfms_count, 2361 sizeof(struct crypto_skcipher *), 2362 GFP_KERNEL); 2363 if (!cc->cipher_tfm.tfms) 2364 return -ENOMEM; 2365 2366 for (i = 0; i < cc->tfms_count; i++) { 2367 cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0, 2368 CRYPTO_ALG_ALLOCATES_MEMORY); 2369 if (IS_ERR(cc->cipher_tfm.tfms[i])) { 2370 err = PTR_ERR(cc->cipher_tfm.tfms[i]); 2371 crypt_free_tfms(cc); 2372 return err; 2373 } 2374 } 2375 2376 /* 2377 * dm-crypt performance can vary greatly depending on which crypto 2378 * algorithm implementation is used. Help people debug performance 2379 * problems by logging the ->cra_driver_name. 2380 */ 2381 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2382 crypto_skcipher_alg(any_tfm(cc))->base.cra_driver_name); 2383 return 0; 2384} 2385 2386static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode) 2387{ 2388 int err; 2389 2390 cc->cipher_tfm.tfms = kmalloc(sizeof(struct crypto_aead *), GFP_KERNEL); 2391 if (!cc->cipher_tfm.tfms) 2392 return -ENOMEM; 2393 2394 cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0, 2395 CRYPTO_ALG_ALLOCATES_MEMORY); 2396 if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2397 err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]); 2398 crypt_free_tfms(cc); 2399 return err; 2400 } 2401 2402 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2403 crypto_aead_alg(any_tfm_aead(cc))->base.cra_driver_name); 2404 return 0; 2405} 2406 2407static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode) 2408{ 2409 if (crypt_integrity_aead(cc)) 2410 return crypt_alloc_tfms_aead(cc, ciphermode); 2411 else 2412 return crypt_alloc_tfms_skcipher(cc, ciphermode); 2413} 2414 2415static unsigned int crypt_subkey_size(struct crypt_config *cc) 2416{ 2417 return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count); 2418} 2419 2420static unsigned int crypt_authenckey_size(struct crypt_config *cc) 2421{ 2422 return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param)); 2423} 2424 2425/* 2426 * If AEAD is composed like authenc(hmac(sha256),xts(aes)), 2427 * the key must be for some reason in special format. 2428 * This funcion converts cc->key to this special format. 2429 */ 2430static void crypt_copy_authenckey(char *p, const void *key, 2431 unsigned int enckeylen, unsigned int authkeylen) 2432{ 2433 struct crypto_authenc_key_param *param; 2434 struct rtattr *rta; 2435 2436 rta = (struct rtattr *)p; 2437 param = RTA_DATA(rta); 2438 param->enckeylen = cpu_to_be32(enckeylen); 2439 rta->rta_len = RTA_LENGTH(sizeof(*param)); 2440 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; 2441 p += RTA_SPACE(sizeof(*param)); 2442 memcpy(p, key + enckeylen, authkeylen); 2443 p += authkeylen; 2444 memcpy(p, key, enckeylen); 2445} 2446 2447static int crypt_setkey(struct crypt_config *cc) 2448{ 2449 unsigned int subkey_size; 2450 int err = 0, i, r; 2451 2452 /* Ignore extra keys (which are used for IV etc) */ 2453 subkey_size = crypt_subkey_size(cc); 2454 2455 if (crypt_integrity_hmac(cc)) { 2456 if (subkey_size < cc->key_mac_size) 2457 return -EINVAL; 2458 2459 crypt_copy_authenckey(cc->authenc_key, cc->key, 2460 subkey_size - cc->key_mac_size, 2461 cc->key_mac_size); 2462 } 2463 2464 for (i = 0; i < cc->tfms_count; i++) { 2465 if (crypt_integrity_hmac(cc)) 2466 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2467 cc->authenc_key, crypt_authenckey_size(cc)); 2468 else if (crypt_integrity_aead(cc)) 2469 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2470 cc->key + (i * subkey_size), 2471 subkey_size); 2472 else 2473 r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i], 2474 cc->key + (i * subkey_size), 2475 subkey_size); 2476 if (r) 2477 err = r; 2478 } 2479 2480 if (crypt_integrity_hmac(cc)) 2481 memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc)); 2482 2483 return err; 2484} 2485 2486#ifdef CONFIG_KEYS 2487 2488static bool contains_whitespace(const char *str) 2489{ 2490 while (*str) 2491 if (isspace(*str++)) 2492 return true; 2493 return false; 2494} 2495 2496static int set_key_user(struct crypt_config *cc, struct key *key) 2497{ 2498 const struct user_key_payload *ukp; 2499 2500 ukp = user_key_payload_locked(key); 2501 if (!ukp) 2502 return -EKEYREVOKED; 2503 2504 if (cc->key_size != ukp->datalen) 2505 return -EINVAL; 2506 2507 memcpy(cc->key, ukp->data, cc->key_size); 2508 2509 return 0; 2510} 2511 2512static int set_key_encrypted(struct crypt_config *cc, struct key *key) 2513{ 2514 const struct encrypted_key_payload *ekp; 2515 2516 ekp = key->payload.data[0]; 2517 if (!ekp) 2518 return -EKEYREVOKED; 2519 2520 if (cc->key_size != ekp->decrypted_datalen) 2521 return -EINVAL; 2522 2523 memcpy(cc->key, ekp->decrypted_data, cc->key_size); 2524 2525 return 0; 2526} 2527 2528static int set_key_trusted(struct crypt_config *cc, struct key *key) 2529{ 2530 const struct trusted_key_payload *tkp; 2531 2532 tkp = key->payload.data[0]; 2533 if (!tkp) 2534 return -EKEYREVOKED; 2535 2536 if (cc->key_size != tkp->key_len) 2537 return -EINVAL; 2538 2539 memcpy(cc->key, tkp->key, cc->key_size); 2540 2541 return 0; 2542} 2543 2544static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2545{ 2546 char *new_key_string, *key_desc; 2547 int ret; 2548 struct key_type *type; 2549 struct key *key; 2550 int (*set_key)(struct crypt_config *cc, struct key *key); 2551 2552 /* 2553 * Reject key_string with whitespace. dm core currently lacks code for 2554 * proper whitespace escaping in arguments on DM_TABLE_STATUS path. 2555 */ 2556 if (contains_whitespace(key_string)) { 2557 DMERR("whitespace chars not allowed in key string"); 2558 return -EINVAL; 2559 } 2560 2561 /* look for next ':' separating key_type from key_description */ 2562 key_desc = strchr(key_string, ':'); 2563 if (!key_desc || key_desc == key_string || !strlen(key_desc + 1)) 2564 return -EINVAL; 2565 2566 if (!strncmp(key_string, "logon:", key_desc - key_string + 1)) { 2567 type = &key_type_logon; 2568 set_key = set_key_user; 2569 } else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) { 2570 type = &key_type_user; 2571 set_key = set_key_user; 2572 } else if (IS_ENABLED(CONFIG_ENCRYPTED_KEYS) && 2573 !strncmp(key_string, "encrypted:", key_desc - key_string + 1)) { 2574 type = &key_type_encrypted; 2575 set_key = set_key_encrypted; 2576 } else if (IS_ENABLED(CONFIG_TRUSTED_KEYS) && 2577 !strncmp(key_string, "trusted:", key_desc - key_string + 1)) { 2578 type = &key_type_trusted; 2579 set_key = set_key_trusted; 2580 } else { 2581 return -EINVAL; 2582 } 2583 2584 new_key_string = kstrdup(key_string, GFP_KERNEL); 2585 if (!new_key_string) 2586 return -ENOMEM; 2587 2588 key = request_key(type, key_desc + 1, NULL); 2589 if (IS_ERR(key)) { 2590 kfree_sensitive(new_key_string); 2591 return PTR_ERR(key); 2592 } 2593 2594 down_read(&key->sem); 2595 2596 ret = set_key(cc, key); 2597 if (ret < 0) { 2598 up_read(&key->sem); 2599 key_put(key); 2600 kfree_sensitive(new_key_string); 2601 return ret; 2602 } 2603 2604 up_read(&key->sem); 2605 key_put(key); 2606 2607 /* clear the flag since following operations may invalidate previously valid key */ 2608 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2609 2610 ret = crypt_setkey(cc); 2611 2612 if (!ret) { 2613 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2614 kfree_sensitive(cc->key_string); 2615 cc->key_string = new_key_string; 2616 } else 2617 kfree_sensitive(new_key_string); 2618 2619 return ret; 2620} 2621 2622static int get_key_size(char **key_string) 2623{ 2624 char *colon, dummy; 2625 int ret; 2626 2627 if (*key_string[0] != ':') 2628 return strlen(*key_string) >> 1; 2629 2630 /* look for next ':' in key string */ 2631 colon = strpbrk(*key_string + 1, ":"); 2632 if (!colon) 2633 return -EINVAL; 2634 2635 if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':') 2636 return -EINVAL; 2637 2638 *key_string = colon; 2639 2640 /* remaining key string should be :<logon|user>:<key_desc> */ 2641 2642 return ret; 2643} 2644 2645#else 2646 2647static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2648{ 2649 return -EINVAL; 2650} 2651 2652static int get_key_size(char **key_string) 2653{ 2654 return (*key_string[0] == ':') ? -EINVAL : (int)(strlen(*key_string) >> 1); 2655} 2656 2657#endif /* CONFIG_KEYS */ 2658 2659static int crypt_set_key(struct crypt_config *cc, char *key) 2660{ 2661 int r = -EINVAL; 2662 int key_string_len = strlen(key); 2663 2664 /* Hyphen (which gives a key_size of zero) means there is no key. */ 2665 if (!cc->key_size && strcmp(key, "-")) 2666 goto out; 2667 2668 /* ':' means the key is in kernel keyring, short-circuit normal key processing */ 2669 if (key[0] == ':') { 2670 r = crypt_set_keyring_key(cc, key + 1); 2671 goto out; 2672 } 2673 2674 /* clear the flag since following operations may invalidate previously valid key */ 2675 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2676 2677 /* wipe references to any kernel keyring key */ 2678 kfree_sensitive(cc->key_string); 2679 cc->key_string = NULL; 2680 2681 /* Decode key from its hex representation. */ 2682 if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0) 2683 goto out; 2684 2685 r = crypt_setkey(cc); 2686 if (!r) 2687 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2688 2689out: 2690 /* Hex key string not needed after here, so wipe it. */ 2691 memset(key, '0', key_string_len); 2692 2693 return r; 2694} 2695 2696static int crypt_wipe_key(struct crypt_config *cc) 2697{ 2698 int r; 2699 2700 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2701 get_random_bytes(&cc->key, cc->key_size); 2702 2703 /* Wipe IV private keys */ 2704 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) { 2705 r = cc->iv_gen_ops->wipe(cc); 2706 if (r) 2707 return r; 2708 } 2709 2710 kfree_sensitive(cc->key_string); 2711 cc->key_string = NULL; 2712 r = crypt_setkey(cc); 2713 memset(&cc->key, 0, cc->key_size * sizeof(u8)); 2714 2715 return r; 2716} 2717 2718static void crypt_calculate_pages_per_client(void) 2719{ 2720 unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100; 2721 2722 if (!dm_crypt_clients_n) 2723 return; 2724 2725 pages /= dm_crypt_clients_n; 2726 if (pages < DM_CRYPT_MIN_PAGES_PER_CLIENT) 2727 pages = DM_CRYPT_MIN_PAGES_PER_CLIENT; 2728 dm_crypt_pages_per_client = pages; 2729} 2730 2731static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data) 2732{ 2733 struct crypt_config *cc = pool_data; 2734 struct page *page; 2735 2736 /* 2737 * Note, percpu_counter_read_positive() may over (and under) estimate 2738 * the current usage by at most (batch - 1) * num_online_cpus() pages, 2739 * but avoids potential spinlock contention of an exact result. 2740 */ 2741 if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) >= dm_crypt_pages_per_client) && 2742 likely(gfp_mask & __GFP_NORETRY)) 2743 return NULL; 2744 2745 page = alloc_page(gfp_mask); 2746 if (likely(page != NULL)) 2747 percpu_counter_add(&cc->n_allocated_pages, 1); 2748 2749 return page; 2750} 2751 2752static void crypt_page_free(void *page, void *pool_data) 2753{ 2754 struct crypt_config *cc = pool_data; 2755 2756 __free_page(page); 2757 percpu_counter_sub(&cc->n_allocated_pages, 1); 2758} 2759 2760static void crypt_dtr(struct dm_target *ti) 2761{ 2762 struct crypt_config *cc = ti->private; 2763 2764 ti->private = NULL; 2765 2766 if (!cc) 2767 return; 2768 2769 if (cc->write_thread) 2770 kthread_stop(cc->write_thread); 2771 2772 if (cc->io_queue) 2773 destroy_workqueue(cc->io_queue); 2774 if (cc->crypt_queue) 2775 destroy_workqueue(cc->crypt_queue); 2776 2777 if (cc->workqueue_id) 2778 ida_free(&workqueue_ida, cc->workqueue_id); 2779 2780 crypt_free_tfms(cc); 2781 2782 bioset_exit(&cc->bs); 2783 2784 mempool_exit(&cc->page_pool); 2785 mempool_exit(&cc->req_pool); 2786 mempool_exit(&cc->tag_pool); 2787 2788 WARN_ON(percpu_counter_sum(&cc->n_allocated_pages) != 0); 2789 percpu_counter_destroy(&cc->n_allocated_pages); 2790 2791 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) 2792 cc->iv_gen_ops->dtr(cc); 2793 2794 if (cc->dev) 2795 dm_put_device(ti, cc->dev); 2796 2797 kfree_sensitive(cc->cipher_string); 2798 kfree_sensitive(cc->key_string); 2799 kfree_sensitive(cc->cipher_auth); 2800 kfree_sensitive(cc->authenc_key); 2801 2802 mutex_destroy(&cc->bio_alloc_lock); 2803 2804 /* Must zero key material before freeing */ 2805 kfree_sensitive(cc); 2806 2807 spin_lock(&dm_crypt_clients_lock); 2808 WARN_ON(!dm_crypt_clients_n); 2809 dm_crypt_clients_n--; 2810 crypt_calculate_pages_per_client(); 2811 spin_unlock(&dm_crypt_clients_lock); 2812 2813 dm_audit_log_dtr(DM_MSG_PREFIX, ti, 1); 2814} 2815 2816static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode) 2817{ 2818 struct crypt_config *cc = ti->private; 2819 2820 if (crypt_integrity_aead(cc)) 2821 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2822 else 2823 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2824 2825 if (cc->iv_size) 2826 /* at least a 64 bit sector number should fit in our buffer */ 2827 cc->iv_size = max(cc->iv_size, 2828 (unsigned int)(sizeof(u64) / sizeof(u8))); 2829 else if (ivmode) { 2830 DMWARN("Selected cipher does not support IVs"); 2831 ivmode = NULL; 2832 } 2833 2834 /* Choose ivmode, see comments at iv code. */ 2835 if (ivmode == NULL) 2836 cc->iv_gen_ops = NULL; 2837 else if (strcmp(ivmode, "plain") == 0) 2838 cc->iv_gen_ops = &crypt_iv_plain_ops; 2839 else if (strcmp(ivmode, "plain64") == 0) 2840 cc->iv_gen_ops = &crypt_iv_plain64_ops; 2841 else if (strcmp(ivmode, "plain64be") == 0) 2842 cc->iv_gen_ops = &crypt_iv_plain64be_ops; 2843 else if (strcmp(ivmode, "essiv") == 0) 2844 cc->iv_gen_ops = &crypt_iv_essiv_ops; 2845 else if (strcmp(ivmode, "benbi") == 0) 2846 cc->iv_gen_ops = &crypt_iv_benbi_ops; 2847 else if (strcmp(ivmode, "null") == 0) 2848 cc->iv_gen_ops = &crypt_iv_null_ops; 2849 else if (strcmp(ivmode, "eboiv") == 0) 2850 cc->iv_gen_ops = &crypt_iv_eboiv_ops; 2851 else if (strcmp(ivmode, "elephant") == 0) { 2852 cc->iv_gen_ops = &crypt_iv_elephant_ops; 2853 cc->key_parts = 2; 2854 cc->key_extra_size = cc->key_size / 2; 2855 if (cc->key_extra_size > ELEPHANT_MAX_KEY_SIZE) 2856 return -EINVAL; 2857 set_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags); 2858 } else if (strcmp(ivmode, "lmk") == 0) { 2859 cc->iv_gen_ops = &crypt_iv_lmk_ops; 2860 /* 2861 * Version 2 and 3 is recognised according 2862 * to length of provided multi-key string. 2863 * If present (version 3), last key is used as IV seed. 2864 * All keys (including IV seed) are always the same size. 2865 */ 2866 if (cc->key_size % cc->key_parts) { 2867 cc->key_parts++; 2868 cc->key_extra_size = cc->key_size / cc->key_parts; 2869 } 2870 } else if (strcmp(ivmode, "tcw") == 0) { 2871 cc->iv_gen_ops = &crypt_iv_tcw_ops; 2872 cc->key_parts += 2; /* IV + whitening */ 2873 cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE; 2874 } else if (strcmp(ivmode, "random") == 0) { 2875 cc->iv_gen_ops = &crypt_iv_random_ops; 2876 /* Need storage space in integrity fields. */ 2877 cc->integrity_iv_size = cc->iv_size; 2878 } else { 2879 ti->error = "Invalid IV mode"; 2880 return -EINVAL; 2881 } 2882 2883 return 0; 2884} 2885 2886/* 2887 * Workaround to parse HMAC algorithm from AEAD crypto API spec. 2888 * The HMAC is needed to calculate tag size (HMAC digest size). 2889 * This should be probably done by crypto-api calls (once available...) 2890 */ 2891static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api) 2892{ 2893 char *start, *end, *mac_alg = NULL; 2894 struct crypto_ahash *mac; 2895 2896 if (!strstarts(cipher_api, "authenc(")) 2897 return 0; 2898 2899 start = strchr(cipher_api, '('); 2900 end = strchr(cipher_api, ','); 2901 if (!start || !end || ++start > end) 2902 return -EINVAL; 2903 2904 mac_alg = kmemdup_nul(start, end - start, GFP_KERNEL); 2905 if (!mac_alg) 2906 return -ENOMEM; 2907 2908 mac = crypto_alloc_ahash(mac_alg, 0, CRYPTO_ALG_ALLOCATES_MEMORY); 2909 kfree(mac_alg); 2910 2911 if (IS_ERR(mac)) 2912 return PTR_ERR(mac); 2913 2914 cc->key_mac_size = crypto_ahash_digestsize(mac); 2915 crypto_free_ahash(mac); 2916 2917 cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL); 2918 if (!cc->authenc_key) 2919 return -ENOMEM; 2920 2921 return 0; 2922} 2923 2924static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key, 2925 char **ivmode, char **ivopts) 2926{ 2927 struct crypt_config *cc = ti->private; 2928 char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME]; 2929 int ret = -EINVAL; 2930 2931 cc->tfms_count = 1; 2932 2933 /* 2934 * New format (capi: prefix) 2935 * capi:cipher_api_spec-iv:ivopts 2936 */ 2937 tmp = &cipher_in[strlen("capi:")]; 2938 2939 /* Separate IV options if present, it can contain another '-' in hash name */ 2940 *ivopts = strrchr(tmp, ':'); 2941 if (*ivopts) { 2942 **ivopts = '\0'; 2943 (*ivopts)++; 2944 } 2945 /* Parse IV mode */ 2946 *ivmode = strrchr(tmp, '-'); 2947 if (*ivmode) { 2948 **ivmode = '\0'; 2949 (*ivmode)++; 2950 } 2951 /* The rest is crypto API spec */ 2952 cipher_api = tmp; 2953 2954 /* Alloc AEAD, can be used only in new format. */ 2955 if (crypt_integrity_aead(cc)) { 2956 ret = crypt_ctr_auth_cipher(cc, cipher_api); 2957 if (ret < 0) { 2958 ti->error = "Invalid AEAD cipher spec"; 2959 return ret; 2960 } 2961 } 2962 2963 if (*ivmode && !strcmp(*ivmode, "lmk")) 2964 cc->tfms_count = 64; 2965 2966 if (*ivmode && !strcmp(*ivmode, "essiv")) { 2967 if (!*ivopts) { 2968 ti->error = "Digest algorithm missing for ESSIV mode"; 2969 return -EINVAL; 2970 } 2971 ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)", 2972 cipher_api, *ivopts); 2973 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 2974 ti->error = "Cannot allocate cipher string"; 2975 return -ENOMEM; 2976 } 2977 cipher_api = buf; 2978 } 2979 2980 cc->key_parts = cc->tfms_count; 2981 2982 /* Allocate cipher */ 2983 ret = crypt_alloc_tfms(cc, cipher_api); 2984 if (ret < 0) { 2985 ti->error = "Error allocating crypto tfm"; 2986 return ret; 2987 } 2988 2989 if (crypt_integrity_aead(cc)) 2990 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2991 else 2992 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2993 2994 return 0; 2995} 2996 2997static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key, 2998 char **ivmode, char **ivopts) 2999{ 3000 struct crypt_config *cc = ti->private; 3001 char *tmp, *cipher, *chainmode, *keycount; 3002 char *cipher_api = NULL; 3003 int ret = -EINVAL; 3004 char dummy; 3005 3006 if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) { 3007 ti->error = "Bad cipher specification"; 3008 return -EINVAL; 3009 } 3010 3011 /* 3012 * Legacy dm-crypt cipher specification 3013 * cipher[:keycount]-mode-iv:ivopts 3014 */ 3015 tmp = cipher_in; 3016 keycount = strsep(&tmp, "-"); 3017 cipher = strsep(&keycount, ":"); 3018 3019 if (!keycount) 3020 cc->tfms_count = 1; 3021 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 || 3022 !is_power_of_2(cc->tfms_count)) { 3023 ti->error = "Bad cipher key count specification"; 3024 return -EINVAL; 3025 } 3026 cc->key_parts = cc->tfms_count; 3027 3028 chainmode = strsep(&tmp, "-"); 3029 *ivmode = strsep(&tmp, ":"); 3030 *ivopts = tmp; 3031 3032 /* 3033 * For compatibility with the original dm-crypt mapping format, if 3034 * only the cipher name is supplied, use cbc-plain. 3035 */ 3036 if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) { 3037 chainmode = "cbc"; 3038 *ivmode = "plain"; 3039 } 3040 3041 if (strcmp(chainmode, "ecb") && !*ivmode) { 3042 ti->error = "IV mechanism required"; 3043 return -EINVAL; 3044 } 3045 3046 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL); 3047 if (!cipher_api) 3048 goto bad_mem; 3049 3050 if (*ivmode && !strcmp(*ivmode, "essiv")) { 3051 if (!*ivopts) { 3052 ti->error = "Digest algorithm missing for ESSIV mode"; 3053 kfree(cipher_api); 3054 return -EINVAL; 3055 } 3056 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 3057 "essiv(%s(%s),%s)", chainmode, cipher, *ivopts); 3058 } else { 3059 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 3060 "%s(%s)", chainmode, cipher); 3061 } 3062 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 3063 kfree(cipher_api); 3064 goto bad_mem; 3065 } 3066 3067 /* Allocate cipher */ 3068 ret = crypt_alloc_tfms(cc, cipher_api); 3069 if (ret < 0) { 3070 ti->error = "Error allocating crypto tfm"; 3071 kfree(cipher_api); 3072 return ret; 3073 } 3074 kfree(cipher_api); 3075 3076 return 0; 3077bad_mem: 3078 ti->error = "Cannot allocate cipher strings"; 3079 return -ENOMEM; 3080} 3081 3082static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key) 3083{ 3084 struct crypt_config *cc = ti->private; 3085 char *ivmode = NULL, *ivopts = NULL; 3086 int ret; 3087 3088 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL); 3089 if (!cc->cipher_string) { 3090 ti->error = "Cannot allocate cipher strings"; 3091 return -ENOMEM; 3092 } 3093 3094 if (strstarts(cipher_in, "capi:")) 3095 ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts); 3096 else 3097 ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts); 3098 if (ret) 3099 return ret; 3100 3101 /* Initialize IV */ 3102 ret = crypt_ctr_ivmode(ti, ivmode); 3103 if (ret < 0) 3104 return ret; 3105 3106 /* Initialize and set key */ 3107 ret = crypt_set_key(cc, key); 3108 if (ret < 0) { 3109 ti->error = "Error decoding and setting key"; 3110 return ret; 3111 } 3112 3113 /* Allocate IV */ 3114 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) { 3115 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts); 3116 if (ret < 0) { 3117 ti->error = "Error creating IV"; 3118 return ret; 3119 } 3120 } 3121 3122 /* Initialize IV (set keys for ESSIV etc) */ 3123 if (cc->iv_gen_ops && cc->iv_gen_ops->init) { 3124 ret = cc->iv_gen_ops->init(cc); 3125 if (ret < 0) { 3126 ti->error = "Error initialising IV"; 3127 return ret; 3128 } 3129 } 3130 3131 /* wipe the kernel key payload copy */ 3132 if (cc->key_string) 3133 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3134 3135 return ret; 3136} 3137 3138static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv) 3139{ 3140 struct crypt_config *cc = ti->private; 3141 struct dm_arg_set as; 3142 static const struct dm_arg _args[] = { 3143 {0, 9, "Invalid number of feature args"}, 3144 }; 3145 unsigned int opt_params, val; 3146 const char *opt_string, *sval; 3147 char dummy; 3148 int ret; 3149 3150 /* Optional parameters */ 3151 as.argc = argc; 3152 as.argv = argv; 3153 3154 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error); 3155 if (ret) 3156 return ret; 3157 3158 while (opt_params--) { 3159 opt_string = dm_shift_arg(&as); 3160 if (!opt_string) { 3161 ti->error = "Not enough feature arguments"; 3162 return -EINVAL; 3163 } 3164 3165 if (!strcasecmp(opt_string, "allow_discards")) 3166 ti->num_discard_bios = 1; 3167 3168 else if (!strcasecmp(opt_string, "same_cpu_crypt")) 3169 set_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3170 else if (!strcasecmp(opt_string, "high_priority")) 3171 set_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags); 3172 3173 else if (!strcasecmp(opt_string, "submit_from_crypt_cpus")) 3174 set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3175 else if (!strcasecmp(opt_string, "no_read_workqueue")) 3176 set_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3177 else if (!strcasecmp(opt_string, "no_write_workqueue")) 3178 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3179 else if (sscanf(opt_string, "integrity:%u:", &val) == 1) { 3180 if (val == 0 || val > MAX_TAG_SIZE) { 3181 ti->error = "Invalid integrity arguments"; 3182 return -EINVAL; 3183 } 3184 cc->on_disk_tag_size = val; 3185 sval = strchr(opt_string + strlen("integrity:"), ':') + 1; 3186 if (!strcasecmp(sval, "aead")) { 3187 set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 3188 } else if (strcasecmp(sval, "none")) { 3189 ti->error = "Unknown integrity profile"; 3190 return -EINVAL; 3191 } 3192 3193 cc->cipher_auth = kstrdup(sval, GFP_KERNEL); 3194 if (!cc->cipher_auth) 3195 return -ENOMEM; 3196 } else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) { 3197 if (cc->sector_size < (1 << SECTOR_SHIFT) || 3198 cc->sector_size > 4096 || 3199 (cc->sector_size & (cc->sector_size - 1))) { 3200 ti->error = "Invalid feature value for sector_size"; 3201 return -EINVAL; 3202 } 3203 if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) { 3204 ti->error = "Device size is not multiple of sector_size feature"; 3205 return -EINVAL; 3206 } 3207 cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT; 3208 } else if (!strcasecmp(opt_string, "iv_large_sectors")) 3209 set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3210 else { 3211 ti->error = "Invalid feature arguments"; 3212 return -EINVAL; 3213 } 3214 } 3215 3216 return 0; 3217} 3218 3219#ifdef CONFIG_BLK_DEV_ZONED 3220static int crypt_report_zones(struct dm_target *ti, 3221 struct dm_report_zones_args *args, unsigned int nr_zones) 3222{ 3223 struct crypt_config *cc = ti->private; 3224 3225 return dm_report_zones(cc->dev->bdev, cc->start, 3226 cc->start + dm_target_offset(ti, args->next_sector), 3227 args, nr_zones); 3228} 3229#else 3230#define crypt_report_zones NULL 3231#endif 3232 3233/* 3234 * Construct an encryption mapping: 3235 * <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start> 3236 */ 3237static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) 3238{ 3239 struct crypt_config *cc; 3240 const char *devname = dm_table_device_name(ti->table); 3241 int key_size, wq_id; 3242 unsigned int align_mask; 3243 unsigned int common_wq_flags; 3244 unsigned long long tmpll; 3245 int ret; 3246 size_t iv_size_padding, additional_req_size; 3247 char dummy; 3248 3249 if (argc < 5) { 3250 ti->error = "Not enough arguments"; 3251 return -EINVAL; 3252 } 3253 3254 key_size = get_key_size(&argv[1]); 3255 if (key_size < 0) { 3256 ti->error = "Cannot parse key size"; 3257 return -EINVAL; 3258 } 3259 3260 cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL); 3261 if (!cc) { 3262 ti->error = "Cannot allocate encryption context"; 3263 return -ENOMEM; 3264 } 3265 cc->key_size = key_size; 3266 cc->sector_size = (1 << SECTOR_SHIFT); 3267 cc->sector_shift = 0; 3268 3269 ti->private = cc; 3270 3271 spin_lock(&dm_crypt_clients_lock); 3272 dm_crypt_clients_n++; 3273 crypt_calculate_pages_per_client(); 3274 spin_unlock(&dm_crypt_clients_lock); 3275 3276 ret = percpu_counter_init(&cc->n_allocated_pages, 0, GFP_KERNEL); 3277 if (ret < 0) 3278 goto bad; 3279 3280 /* Optional parameters need to be read before cipher constructor */ 3281 if (argc > 5) { 3282 ret = crypt_ctr_optional(ti, argc - 5, &argv[5]); 3283 if (ret) 3284 goto bad; 3285 } 3286 3287 ret = crypt_ctr_cipher(ti, argv[0], argv[1]); 3288 if (ret < 0) 3289 goto bad; 3290 3291 if (crypt_integrity_aead(cc)) { 3292 cc->dmreq_start = sizeof(struct aead_request); 3293 cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc)); 3294 align_mask = crypto_aead_alignmask(any_tfm_aead(cc)); 3295 } else { 3296 cc->dmreq_start = sizeof(struct skcipher_request); 3297 cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc)); 3298 align_mask = crypto_skcipher_alignmask(any_tfm(cc)); 3299 } 3300 cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request)); 3301 3302 if (align_mask < CRYPTO_MINALIGN) { 3303 /* Allocate the padding exactly */ 3304 iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request)) 3305 & align_mask; 3306 } else { 3307 /* 3308 * If the cipher requires greater alignment than kmalloc 3309 * alignment, we don't know the exact position of the 3310 * initialization vector. We must assume worst case. 3311 */ 3312 iv_size_padding = align_mask; 3313 } 3314 3315 /* ...| IV + padding | original IV | original sec. number | bio tag offset | */ 3316 additional_req_size = sizeof(struct dm_crypt_request) + 3317 iv_size_padding + cc->iv_size + 3318 cc->iv_size + 3319 sizeof(uint64_t) + 3320 sizeof(unsigned int); 3321 3322 ret = mempool_init_kmalloc_pool(&cc->req_pool, MIN_IOS, cc->dmreq_start + additional_req_size); 3323 if (ret) { 3324 ti->error = "Cannot allocate crypt request mempool"; 3325 goto bad; 3326 } 3327 3328 cc->per_bio_data_size = ti->per_io_data_size = 3329 ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size, 3330 ARCH_DMA_MINALIGN); 3331 3332 ret = mempool_init(&cc->page_pool, BIO_MAX_VECS, crypt_page_alloc, crypt_page_free, cc); 3333 if (ret) { 3334 ti->error = "Cannot allocate page mempool"; 3335 goto bad; 3336 } 3337 3338 ret = bioset_init(&cc->bs, MIN_IOS, 0, BIOSET_NEED_BVECS); 3339 if (ret) { 3340 ti->error = "Cannot allocate crypt bioset"; 3341 goto bad; 3342 } 3343 3344 mutex_init(&cc->bio_alloc_lock); 3345 3346 ret = -EINVAL; 3347 if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) || 3348 (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) { 3349 ti->error = "Invalid iv_offset sector"; 3350 goto bad; 3351 } 3352 cc->iv_offset = tmpll; 3353 3354 ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev); 3355 if (ret) { 3356 ti->error = "Device lookup failed"; 3357 goto bad; 3358 } 3359 3360 ret = -EINVAL; 3361 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) { 3362 ti->error = "Invalid device sector"; 3363 goto bad; 3364 } 3365 cc->start = tmpll; 3366 3367 if (bdev_is_zoned(cc->dev->bdev)) { 3368 /* 3369 * For zoned block devices, we need to preserve the issuer write 3370 * ordering. To do so, disable write workqueues and force inline 3371 * encryption completion. 3372 */ 3373 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3374 set_bit(DM_CRYPT_WRITE_INLINE, &cc->flags); 3375 3376 /* 3377 * All zone append writes to a zone of a zoned block device will 3378 * have the same BIO sector, the start of the zone. When the 3379 * cypher IV mode uses sector values, all data targeting a 3380 * zone will be encrypted using the first sector numbers of the 3381 * zone. This will not result in write errors but will 3382 * cause most reads to fail as reads will use the sector values 3383 * for the actual data locations, resulting in IV mismatch. 3384 * To avoid this problem, ask DM core to emulate zone append 3385 * operations with regular writes. 3386 */ 3387 DMDEBUG("Zone append operations will be emulated"); 3388 ti->emulate_zone_append = true; 3389 } 3390 3391 if (crypt_integrity_aead(cc) || cc->integrity_iv_size) { 3392 ret = crypt_integrity_ctr(cc, ti); 3393 if (ret) 3394 goto bad; 3395 3396 cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->on_disk_tag_size; 3397 if (!cc->tag_pool_max_sectors) 3398 cc->tag_pool_max_sectors = 1; 3399 3400 ret = mempool_init_kmalloc_pool(&cc->tag_pool, MIN_IOS, 3401 cc->tag_pool_max_sectors * cc->on_disk_tag_size); 3402 if (ret) { 3403 ti->error = "Cannot allocate integrity tags mempool"; 3404 goto bad; 3405 } 3406 3407 cc->tag_pool_max_sectors <<= cc->sector_shift; 3408 } 3409 3410 wq_id = ida_alloc_min(&workqueue_ida, 1, GFP_KERNEL); 3411 if (wq_id < 0) { 3412 ti->error = "Couldn't get workqueue id"; 3413 ret = wq_id; 3414 goto bad; 3415 } 3416 cc->workqueue_id = wq_id; 3417 3418 ret = -ENOMEM; 3419 common_wq_flags = WQ_MEM_RECLAIM | WQ_SYSFS; 3420 if (test_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags)) 3421 common_wq_flags |= WQ_HIGHPRI; 3422 3423 cc->io_queue = alloc_workqueue("kcryptd_io-%s-%d", common_wq_flags, 1, devname, wq_id); 3424 if (!cc->io_queue) { 3425 ti->error = "Couldn't create kcryptd io queue"; 3426 goto bad; 3427 } 3428 3429 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) { 3430 cc->crypt_queue = alloc_workqueue("kcryptd-%s-%d", 3431 common_wq_flags | WQ_CPU_INTENSIVE, 3432 1, devname, wq_id); 3433 } else { 3434 /* 3435 * While crypt_queue is certainly CPU intensive, the use of 3436 * WQ_CPU_INTENSIVE is meaningless with WQ_UNBOUND. 3437 */ 3438 cc->crypt_queue = alloc_workqueue("kcryptd-%s-%d", 3439 common_wq_flags | WQ_UNBOUND, 3440 num_online_cpus(), devname, wq_id); 3441 } 3442 if (!cc->crypt_queue) { 3443 ti->error = "Couldn't create kcryptd queue"; 3444 goto bad; 3445 } 3446 3447 spin_lock_init(&cc->write_thread_lock); 3448 cc->write_tree = RB_ROOT; 3449 3450 cc->write_thread = kthread_run(dmcrypt_write, cc, "dmcrypt_write/%s", devname); 3451 if (IS_ERR(cc->write_thread)) { 3452 ret = PTR_ERR(cc->write_thread); 3453 cc->write_thread = NULL; 3454 ti->error = "Couldn't spawn write thread"; 3455 goto bad; 3456 } 3457 if (test_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags)) 3458 set_user_nice(cc->write_thread, MIN_NICE); 3459 3460 ti->num_flush_bios = 1; 3461 ti->limit_swap_bios = true; 3462 ti->accounts_remapped_io = true; 3463 3464 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 1); 3465 return 0; 3466 3467bad: 3468 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 0); 3469 crypt_dtr(ti); 3470 return ret; 3471} 3472 3473static int crypt_map(struct dm_target *ti, struct bio *bio) 3474{ 3475 struct dm_crypt_io *io; 3476 struct crypt_config *cc = ti->private; 3477 3478 /* 3479 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues. 3480 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight 3481 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters 3482 */ 3483 if (unlikely(bio->bi_opf & REQ_PREFLUSH || 3484 bio_op(bio) == REQ_OP_DISCARD)) { 3485 bio_set_dev(bio, cc->dev->bdev); 3486 if (bio_sectors(bio)) 3487 bio->bi_iter.bi_sector = cc->start + 3488 dm_target_offset(ti, bio->bi_iter.bi_sector); 3489 return DM_MAPIO_REMAPPED; 3490 } 3491 3492 /* 3493 * Check if bio is too large, split as needed. 3494 */ 3495 if (unlikely(bio->bi_iter.bi_size > (BIO_MAX_VECS << PAGE_SHIFT)) && 3496 (bio_data_dir(bio) == WRITE || cc->on_disk_tag_size)) 3497 dm_accept_partial_bio(bio, ((BIO_MAX_VECS << PAGE_SHIFT) >> SECTOR_SHIFT)); 3498 3499 /* 3500 * Ensure that bio is a multiple of internal sector encryption size 3501 * and is aligned to this size as defined in IO hints. 3502 */ 3503 if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0)) 3504 return DM_MAPIO_KILL; 3505 3506 if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1))) 3507 return DM_MAPIO_KILL; 3508 3509 io = dm_per_bio_data(bio, cc->per_bio_data_size); 3510 crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector)); 3511 3512 if (cc->on_disk_tag_size) { 3513 unsigned int tag_len = cc->on_disk_tag_size * (bio_sectors(bio) >> cc->sector_shift); 3514 3515 if (unlikely(tag_len > KMALLOC_MAX_SIZE)) 3516 io->integrity_metadata = NULL; 3517 else 3518 io->integrity_metadata = kmalloc(tag_len, GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN); 3519 3520 if (unlikely(!io->integrity_metadata)) { 3521 if (bio_sectors(bio) > cc->tag_pool_max_sectors) 3522 dm_accept_partial_bio(bio, cc->tag_pool_max_sectors); 3523 io->integrity_metadata = mempool_alloc(&cc->tag_pool, GFP_NOIO); 3524 io->integrity_metadata_from_pool = true; 3525 } 3526 } 3527 3528 if (crypt_integrity_aead(cc)) 3529 io->ctx.r.req_aead = (struct aead_request *)(io + 1); 3530 else 3531 io->ctx.r.req = (struct skcipher_request *)(io + 1); 3532 3533 if (bio_data_dir(io->base_bio) == READ) { 3534 if (kcryptd_io_read(io, CRYPT_MAP_READ_GFP)) 3535 kcryptd_queue_read(io); 3536 } else 3537 kcryptd_queue_crypt(io); 3538 3539 return DM_MAPIO_SUBMITTED; 3540} 3541 3542static char hex2asc(unsigned char c) 3543{ 3544 return c + '0' + ((unsigned int)(9 - c) >> 4 & 0x27); 3545} 3546 3547static void crypt_status(struct dm_target *ti, status_type_t type, 3548 unsigned int status_flags, char *result, unsigned int maxlen) 3549{ 3550 struct crypt_config *cc = ti->private; 3551 unsigned int i, sz = 0; 3552 int num_feature_args = 0; 3553 3554 switch (type) { 3555 case STATUSTYPE_INFO: 3556 result[0] = '\0'; 3557 break; 3558 3559 case STATUSTYPE_TABLE: 3560 DMEMIT("%s ", cc->cipher_string); 3561 3562 if (cc->key_size > 0) { 3563 if (cc->key_string) 3564 DMEMIT(":%u:%s", cc->key_size, cc->key_string); 3565 else { 3566 for (i = 0; i < cc->key_size; i++) { 3567 DMEMIT("%c%c", hex2asc(cc->key[i] >> 4), 3568 hex2asc(cc->key[i] & 0xf)); 3569 } 3570 } 3571 } else 3572 DMEMIT("-"); 3573 3574 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, 3575 cc->dev->name, (unsigned long long)cc->start); 3576 3577 num_feature_args += !!ti->num_discard_bios; 3578 num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3579 num_feature_args += test_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags); 3580 num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3581 num_feature_args += test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3582 num_feature_args += test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3583 num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT); 3584 num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3585 if (cc->on_disk_tag_size) 3586 num_feature_args++; 3587 if (num_feature_args) { 3588 DMEMIT(" %d", num_feature_args); 3589 if (ti->num_discard_bios) 3590 DMEMIT(" allow_discards"); 3591 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3592 DMEMIT(" same_cpu_crypt"); 3593 if (test_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags)) 3594 DMEMIT(" high_priority"); 3595 if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) 3596 DMEMIT(" submit_from_crypt_cpus"); 3597 if (test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) 3598 DMEMIT(" no_read_workqueue"); 3599 if (test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) 3600 DMEMIT(" no_write_workqueue"); 3601 if (cc->on_disk_tag_size) 3602 DMEMIT(" integrity:%u:%s", cc->on_disk_tag_size, cc->cipher_auth); 3603 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3604 DMEMIT(" sector_size:%d", cc->sector_size); 3605 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 3606 DMEMIT(" iv_large_sectors"); 3607 } 3608 break; 3609 3610 case STATUSTYPE_IMA: 3611 DMEMIT_TARGET_NAME_VERSION(ti->type); 3612 DMEMIT(",allow_discards=%c", ti->num_discard_bios ? 'y' : 'n'); 3613 DMEMIT(",same_cpu_crypt=%c", test_bit(DM_CRYPT_SAME_CPU, &cc->flags) ? 'y' : 'n'); 3614 DMEMIT(",high_priority=%c", test_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags) ? 'y' : 'n'); 3615 DMEMIT(",submit_from_crypt_cpus=%c", test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags) ? 3616 'y' : 'n'); 3617 DMEMIT(",no_read_workqueue=%c", test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags) ? 3618 'y' : 'n'); 3619 DMEMIT(",no_write_workqueue=%c", test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags) ? 3620 'y' : 'n'); 3621 DMEMIT(",iv_large_sectors=%c", test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags) ? 3622 'y' : 'n'); 3623 3624 if (cc->on_disk_tag_size) 3625 DMEMIT(",integrity_tag_size=%u,cipher_auth=%s", 3626 cc->on_disk_tag_size, cc->cipher_auth); 3627 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3628 DMEMIT(",sector_size=%d", cc->sector_size); 3629 if (cc->cipher_string) 3630 DMEMIT(",cipher_string=%s", cc->cipher_string); 3631 3632 DMEMIT(",key_size=%u", cc->key_size); 3633 DMEMIT(",key_parts=%u", cc->key_parts); 3634 DMEMIT(",key_extra_size=%u", cc->key_extra_size); 3635 DMEMIT(",key_mac_size=%u", cc->key_mac_size); 3636 DMEMIT(";"); 3637 break; 3638 } 3639} 3640 3641static void crypt_postsuspend(struct dm_target *ti) 3642{ 3643 struct crypt_config *cc = ti->private; 3644 3645 set_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3646} 3647 3648static int crypt_preresume(struct dm_target *ti) 3649{ 3650 struct crypt_config *cc = ti->private; 3651 3652 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { 3653 DMERR("aborting resume - crypt key is not set."); 3654 return -EAGAIN; 3655 } 3656 3657 return 0; 3658} 3659 3660static void crypt_resume(struct dm_target *ti) 3661{ 3662 struct crypt_config *cc = ti->private; 3663 3664 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3665} 3666 3667/* Message interface 3668 * key set <key> 3669 * key wipe 3670 */ 3671static int crypt_message(struct dm_target *ti, unsigned int argc, char **argv, 3672 char *result, unsigned int maxlen) 3673{ 3674 struct crypt_config *cc = ti->private; 3675 int key_size, ret = -EINVAL; 3676 3677 if (argc < 2) 3678 goto error; 3679 3680 if (!strcasecmp(argv[0], "key")) { 3681 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { 3682 DMWARN("not suspended during key manipulation."); 3683 return -EINVAL; 3684 } 3685 if (argc == 3 && !strcasecmp(argv[1], "set")) { 3686 /* The key size may not be changed. */ 3687 key_size = get_key_size(&argv[2]); 3688 if (key_size < 0 || cc->key_size != key_size) { 3689 memset(argv[2], '0', strlen(argv[2])); 3690 return -EINVAL; 3691 } 3692 3693 ret = crypt_set_key(cc, argv[2]); 3694 if (ret) 3695 return ret; 3696 if (cc->iv_gen_ops && cc->iv_gen_ops->init) 3697 ret = cc->iv_gen_ops->init(cc); 3698 /* wipe the kernel key payload copy */ 3699 if (cc->key_string) 3700 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3701 return ret; 3702 } 3703 if (argc == 2 && !strcasecmp(argv[1], "wipe")) 3704 return crypt_wipe_key(cc); 3705 } 3706 3707error: 3708 DMWARN("unrecognised message received."); 3709 return -EINVAL; 3710} 3711 3712static int crypt_iterate_devices(struct dm_target *ti, 3713 iterate_devices_callout_fn fn, void *data) 3714{ 3715 struct crypt_config *cc = ti->private; 3716 3717 return fn(ti, cc->dev, cc->start, ti->len, data); 3718} 3719 3720static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits) 3721{ 3722 struct crypt_config *cc = ti->private; 3723 3724 limits->logical_block_size = 3725 max_t(unsigned int, limits->logical_block_size, cc->sector_size); 3726 limits->physical_block_size = 3727 max_t(unsigned int, limits->physical_block_size, cc->sector_size); 3728 limits->io_min = max_t(unsigned int, limits->io_min, cc->sector_size); 3729 limits->dma_alignment = limits->logical_block_size - 1; 3730} 3731 3732static struct target_type crypt_target = { 3733 .name = "crypt", 3734 .version = {1, 26, 0}, 3735 .module = THIS_MODULE, 3736 .ctr = crypt_ctr, 3737 .dtr = crypt_dtr, 3738 .features = DM_TARGET_ZONED_HM, 3739 .report_zones = crypt_report_zones, 3740 .map = crypt_map, 3741 .status = crypt_status, 3742 .postsuspend = crypt_postsuspend, 3743 .preresume = crypt_preresume, 3744 .resume = crypt_resume, 3745 .message = crypt_message, 3746 .iterate_devices = crypt_iterate_devices, 3747 .io_hints = crypt_io_hints, 3748}; 3749module_dm(crypt); 3750 3751MODULE_AUTHOR("Jana Saout <jana@saout.de>"); 3752MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); 3753MODULE_LICENSE("GPL"); 3754