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/hex.h> 15 #include <linux/init.h> 16 #include <linux/kernel.h> 17 #include <linux/key.h> 18 #include <linux/bio.h> 19 #include <linux/blkdev.h> 20 #include <linux/blk-integrity.h> 21 #include <linux/crc32.h> 22 #include <linux/mempool.h> 23 #include <linux/slab.h> 24 #include <linux/crypto.h> 25 #include <linux/fips.h> 26 #include <linux/workqueue.h> 27 #include <linux/kthread.h> 28 #include <linux/backing-dev.h> 29 #include <linux/atomic.h> 30 #include <linux/scatterlist.h> 31 #include <linux/rbtree.h> 32 #include <linux/ctype.h> 33 #include <asm/page.h> 34 #include <linux/unaligned.h> 35 #include <crypto/aes.h> 36 #include <crypto/hash.h> 37 #include <crypto/md5.h> 38 #include <crypto/skcipher.h> 39 #include <crypto/aead.h> 40 #include <crypto/authenc.h> 41 #include <crypto/utils.h> 42 #include <linux/rtnetlink.h> /* for struct rtattr and RTA macros only */ 43 #include <linux/key-type.h> 44 #include <keys/user-type.h> 45 #include <keys/encrypted-type.h> 46 #include <keys/trusted-type.h> 47 48 #include <linux/device-mapper.h> 49 50 #include "dm-audit.h" 51 52 #define DM_MSG_PREFIX "crypt" 53 54 static DEFINE_IDA(workqueue_ida); 55 56 /* 57 * context holding the current state of a multi-part conversion 58 */ 59 struct convert_context { 60 struct completion restart; 61 struct bio *bio_in; 62 struct bvec_iter iter_in; 63 struct bio *bio_out; 64 struct bvec_iter iter_out; 65 atomic_t cc_pending; 66 unsigned int tag_offset; 67 u64 cc_sector; 68 union { 69 struct skcipher_request *req; 70 struct aead_request *req_aead; 71 } r; 72 bool aead_recheck; 73 bool aead_failed; 74 75 }; 76 77 /* 78 * per bio private data 79 */ 80 struct dm_crypt_io { 81 struct crypt_config *cc; 82 struct bio *base_bio; 83 u8 *integrity_metadata; 84 bool integrity_metadata_from_pool:1; 85 86 struct work_struct work; 87 88 struct convert_context ctx; 89 90 atomic_t io_pending; 91 blk_status_t error; 92 sector_t sector; 93 94 struct bvec_iter saved_bi_iter; 95 96 struct rb_node rb_node; 97 } CRYPTO_MINALIGN_ATTR; 98 99 struct dm_crypt_request { 100 struct convert_context *ctx; 101 struct scatterlist sg_in[4]; 102 struct scatterlist sg_out[4]; 103 u64 iv_sector; 104 }; 105 106 struct crypt_config; 107 108 struct crypt_iv_operations { 109 int (*ctr)(struct crypt_config *cc, struct dm_target *ti, 110 const char *opts); 111 void (*dtr)(struct crypt_config *cc); 112 int (*init)(struct crypt_config *cc); 113 void (*wipe)(struct crypt_config *cc); 114 int (*generator)(struct crypt_config *cc, u8 *iv, 115 struct dm_crypt_request *dmreq); 116 void (*post)(struct crypt_config *cc, u8 *iv, 117 struct dm_crypt_request *dmreq); 118 }; 119 120 struct iv_benbi_private { 121 int shift; 122 }; 123 124 #define LMK_SEED_SIZE 64 /* hash + 0 */ 125 struct iv_lmk_private { 126 u8 *seed; 127 }; 128 129 #define TCW_WHITENING_SIZE 16 130 struct iv_tcw_private { 131 u8 *iv_seed; 132 u8 *whitening; 133 }; 134 135 #define ELEPHANT_MAX_KEY_SIZE 32 136 struct iv_elephant_private { 137 struct aes_enckey *key; 138 }; 139 140 /* 141 * Crypt: maps a linear range of a block device 142 * and encrypts / decrypts at the same time. 143 */ 144 enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID, 145 DM_CRYPT_SAME_CPU, DM_CRYPT_HIGH_PRIORITY, 146 DM_CRYPT_NO_OFFLOAD, DM_CRYPT_NO_READ_WORKQUEUE, 147 DM_CRYPT_NO_WRITE_WORKQUEUE, DM_CRYPT_WRITE_INLINE }; 148 149 enum cipher_flags { 150 CRYPT_MODE_INTEGRITY_AEAD, /* Use authenticated mode for cipher */ 151 CRYPT_IV_LARGE_SECTORS, /* Calculate IV from sector_size, not 512B sectors */ 152 CRYPT_ENCRYPT_PREPROCESS, /* Must preprocess data for encryption (elephant) */ 153 CRYPT_KEY_MAC_SIZE_SET, /* The integrity_key_size option was used */ 154 }; 155 156 /* 157 * The fields in here must be read only after initialization. 158 */ 159 struct crypt_config { 160 struct dm_dev *dev; 161 sector_t start; 162 163 struct percpu_counter n_allocated_pages; 164 165 struct workqueue_struct *io_queue; 166 struct workqueue_struct *crypt_queue; 167 168 spinlock_t write_thread_lock; 169 struct task_struct *write_thread; 170 struct rb_root write_tree; 171 172 char *cipher_string; 173 char *cipher_auth; 174 char *key_string; 175 176 const struct crypt_iv_operations *iv_gen_ops; 177 union { 178 struct iv_benbi_private benbi; 179 struct iv_lmk_private lmk; 180 struct iv_tcw_private tcw; 181 struct iv_elephant_private elephant; 182 } iv_gen_private; 183 u64 iv_offset; 184 unsigned int iv_size; 185 unsigned short sector_size; 186 unsigned char sector_shift; 187 188 union { 189 struct crypto_skcipher **tfms; 190 struct crypto_aead **tfms_aead; 191 } cipher_tfm; 192 unsigned int tfms_count; 193 int workqueue_id; 194 unsigned long cipher_flags; 195 196 /* 197 * Layout of each crypto request: 198 * 199 * struct skcipher_request 200 * context 201 * padding 202 * struct dm_crypt_request 203 * padding 204 * IV 205 * 206 * The padding is added so that dm_crypt_request and the IV are 207 * correctly aligned. 208 */ 209 unsigned int dmreq_start; 210 211 unsigned int per_bio_data_size; 212 213 unsigned long flags; 214 unsigned int key_size; 215 unsigned int key_parts; /* independent parts in key buffer */ 216 unsigned int key_extra_size; /* additional keys length */ 217 unsigned int key_mac_size; /* MAC key size for authenc(...) */ 218 219 unsigned int integrity_tag_size; 220 unsigned int integrity_iv_size; 221 unsigned int used_tag_size; 222 unsigned int tuple_size; 223 224 /* 225 * pool for per bio private data, crypto requests, 226 * encryption requeusts/buffer pages and integrity tags 227 */ 228 unsigned int tag_pool_max_sectors; 229 mempool_t tag_pool; 230 mempool_t req_pool; 231 mempool_t page_pool; 232 233 struct bio_set bs; 234 struct mutex bio_alloc_lock; 235 236 u8 *authenc_key; /* space for keys in authenc() format (if used) */ 237 u8 key[] __counted_by(key_size); 238 }; 239 240 #define MIN_IOS 64 241 #define MAX_TAG_SIZE 480 242 #define POOL_ENTRY_SIZE 512 243 244 static DEFINE_SPINLOCK(dm_crypt_clients_lock); 245 static unsigned int dm_crypt_clients_n; 246 static volatile unsigned long dm_crypt_pages_per_client; 247 #define DM_CRYPT_MEMORY_PERCENT 2 248 #define DM_CRYPT_MIN_PAGES_PER_CLIENT (BIO_MAX_VECS * 16) 249 #define DM_CRYPT_DEFAULT_MAX_READ_SIZE 131072 250 #define DM_CRYPT_DEFAULT_MAX_WRITE_SIZE 131072 251 252 static unsigned int max_read_size = 0; 253 module_param(max_read_size, uint, 0644); 254 MODULE_PARM_DESC(max_read_size, "Maximum size of a read request"); 255 static unsigned int max_write_size = 0; 256 module_param(max_write_size, uint, 0644); 257 MODULE_PARM_DESC(max_write_size, "Maximum size of a write request"); 258 259 static unsigned get_max_request_sectors(struct dm_target *ti, struct bio *bio, bool no_split) 260 { 261 struct crypt_config *cc = ti->private; 262 unsigned val, sector_align; 263 bool wrt = op_is_write(bio_op(bio)); 264 265 if (no_split) { 266 val = -1; 267 } else if (wrt) { 268 val = min_not_zero(READ_ONCE(max_write_size), 269 DM_CRYPT_DEFAULT_MAX_WRITE_SIZE); 270 } else { 271 val = min_not_zero(READ_ONCE(max_read_size), 272 DM_CRYPT_DEFAULT_MAX_READ_SIZE); 273 } 274 275 if (wrt || cc->used_tag_size) 276 val = min(val, BIO_MAX_VECS << PAGE_SHIFT); 277 278 sector_align = max(bdev_logical_block_size(cc->dev->bdev), 279 (unsigned)cc->sector_size); 280 val = round_down(val, sector_align); 281 if (unlikely(!val)) 282 val = sector_align; 283 return val >> SECTOR_SHIFT; 284 } 285 286 static void crypt_endio(struct bio *clone); 287 static void kcryptd_queue_crypt(struct dm_crypt_io *io); 288 static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 289 struct scatterlist *sg); 290 291 static bool crypt_integrity_aead(struct crypt_config *cc); 292 293 /* 294 * Use this to access cipher attributes that are independent of the key. 295 */ 296 static struct crypto_skcipher *any_tfm(struct crypt_config *cc) 297 { 298 return cc->cipher_tfm.tfms[0]; 299 } 300 301 static struct crypto_aead *any_tfm_aead(struct crypt_config *cc) 302 { 303 return cc->cipher_tfm.tfms_aead[0]; 304 } 305 306 /* 307 * Different IV generation algorithms: 308 * 309 * plain: the initial vector is the 32-bit little-endian version of the sector 310 * number, padded with zeros if necessary. 311 * 312 * plain64: the initial vector is the 64-bit little-endian version of the sector 313 * number, padded with zeros if necessary. 314 * 315 * plain64be: the initial vector is the 64-bit big-endian version of the sector 316 * number, padded with zeros if necessary. 317 * 318 * essiv: "encrypted sector|salt initial vector", the sector number is 319 * encrypted with the bulk cipher using a salt as key. The salt 320 * should be derived from the bulk cipher's key via hashing. 321 * 322 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 323 * (needed for LRW-32-AES and possible other narrow block modes) 324 * 325 * null: the initial vector is always zero. Provides compatibility with 326 * obsolete loop_fish2 devices. Do not use for new devices. 327 * 328 * lmk: Compatible implementation of the block chaining mode used 329 * by the Loop-AES block device encryption system 330 * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/ 331 * It operates on full 512 byte sectors and uses CBC 332 * with an IV derived from the sector number, the data and 333 * optionally extra IV seed. 334 * This means that after decryption the first block 335 * of sector must be tweaked according to decrypted data. 336 * Loop-AES can use three encryption schemes: 337 * version 1: is plain aes-cbc mode 338 * version 2: uses 64 multikey scheme with lmk IV generator 339 * version 3: the same as version 2 with additional IV seed 340 * (it uses 65 keys, last key is used as IV seed) 341 * 342 * tcw: Compatible implementation of the block chaining mode used 343 * by the TrueCrypt device encryption system (prior to version 4.1). 344 * For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat 345 * It operates on full 512 byte sectors and uses CBC 346 * with an IV derived from initial key and the sector number. 347 * In addition, whitening value is applied on every sector, whitening 348 * is calculated from initial key, sector number and mixed using CRC32. 349 * Note that this encryption scheme is vulnerable to watermarking attacks 350 * and should be used for old compatible containers access only. 351 * 352 * eboiv: Encrypted byte-offset IV (used in Bitlocker in CBC mode) 353 * The IV is encrypted little-endian byte-offset (with the same key 354 * and cipher as the volume). 355 * 356 * elephant: The extended version of eboiv with additional Elephant diffuser 357 * used with Bitlocker CBC mode. 358 * This mode was used in older Windows systems 359 * https://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf 360 */ 361 362 static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv, 363 struct dm_crypt_request *dmreq) 364 { 365 memset(iv, 0, cc->iv_size); 366 *(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff); 367 368 return 0; 369 } 370 371 static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv, 372 struct dm_crypt_request *dmreq) 373 { 374 memset(iv, 0, cc->iv_size); 375 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 376 377 return 0; 378 } 379 380 static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv, 381 struct dm_crypt_request *dmreq) 382 { 383 memset(iv, 0, cc->iv_size); 384 /* iv_size is at least of size u64; usually it is 16 bytes */ 385 *(__be64 *)&iv[cc->iv_size - sizeof(u64)] = cpu_to_be64(dmreq->iv_sector); 386 387 return 0; 388 } 389 390 static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv, 391 struct dm_crypt_request *dmreq) 392 { 393 /* 394 * ESSIV encryption of the IV is now handled by the crypto API, 395 * so just pass the plain sector number here. 396 */ 397 memset(iv, 0, cc->iv_size); 398 *(__le64 *)iv = cpu_to_le64(dmreq->iv_sector); 399 400 return 0; 401 } 402 403 static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti, 404 const char *opts) 405 { 406 unsigned int bs; 407 int log; 408 409 if (crypt_integrity_aead(cc)) 410 bs = crypto_aead_blocksize(any_tfm_aead(cc)); 411 else 412 bs = crypto_skcipher_blocksize(any_tfm(cc)); 413 log = ilog2(bs); 414 415 /* 416 * We need to calculate how far we must shift the sector count 417 * to get the cipher block count, we use this shift in _gen. 418 */ 419 if (1 << log != bs) { 420 ti->error = "cypher blocksize is not a power of 2"; 421 return -EINVAL; 422 } 423 424 if (log > 9) { 425 ti->error = "cypher blocksize is > 512"; 426 return -EINVAL; 427 } 428 429 cc->iv_gen_private.benbi.shift = 9 - log; 430 431 return 0; 432 } 433 434 static void crypt_iv_benbi_dtr(struct crypt_config *cc) 435 { 436 } 437 438 static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv, 439 struct dm_crypt_request *dmreq) 440 { 441 __be64 val; 442 443 memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */ 444 445 val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1); 446 put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64))); 447 448 return 0; 449 } 450 451 static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv, 452 struct dm_crypt_request *dmreq) 453 { 454 memset(iv, 0, cc->iv_size); 455 456 return 0; 457 } 458 459 static void crypt_iv_lmk_dtr(struct crypt_config *cc) 460 { 461 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 462 463 kfree_sensitive(lmk->seed); 464 lmk->seed = NULL; 465 } 466 467 static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti, 468 const char *opts) 469 { 470 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 471 472 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 473 ti->error = "Unsupported sector size for LMK"; 474 return -EINVAL; 475 } 476 477 if (fips_enabled) { 478 ti->error = "LMK support is disabled due to FIPS"; 479 /* ... because it uses MD5. */ 480 return -EINVAL; 481 } 482 483 /* No seed in LMK version 2 */ 484 if (cc->key_parts == cc->tfms_count) { 485 lmk->seed = NULL; 486 return 0; 487 } 488 489 lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL); 490 if (!lmk->seed) { 491 ti->error = "Error kmallocing seed storage in LMK"; 492 return -ENOMEM; 493 } 494 495 return 0; 496 } 497 498 static int crypt_iv_lmk_init(struct crypt_config *cc) 499 { 500 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 501 int subkey_size = cc->key_size / cc->key_parts; 502 503 /* LMK seed is on the position of LMK_KEYS + 1 key */ 504 if (lmk->seed) 505 memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size), 506 MD5_DIGEST_SIZE); 507 508 return 0; 509 } 510 511 static void crypt_iv_lmk_wipe(struct crypt_config *cc) 512 { 513 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 514 515 if (lmk->seed) 516 memset(lmk->seed, 0, LMK_SEED_SIZE); 517 } 518 519 static void crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv, 520 struct dm_crypt_request *dmreq, u8 *data) 521 { 522 struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk; 523 struct md5_ctx ctx; 524 __le32 buf[4]; 525 526 md5_init(&ctx); 527 528 if (lmk->seed) 529 md5_update(&ctx, lmk->seed, LMK_SEED_SIZE); 530 531 /* Sector is always 512B, block size 16, add data of blocks 1-31 */ 532 md5_update(&ctx, data + 16, 16 * 31); 533 534 /* Sector is cropped to 56 bits here */ 535 buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF); 536 buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000); 537 buf[2] = cpu_to_le32(4024); 538 buf[3] = 0; 539 md5_update(&ctx, (u8 *)buf, sizeof(buf)); 540 541 /* No MD5 padding here */ 542 cpu_to_le32_array(ctx.state.h, ARRAY_SIZE(ctx.state.h)); 543 memcpy(iv, ctx.state.h, cc->iv_size); 544 } 545 546 static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv, 547 struct dm_crypt_request *dmreq) 548 { 549 struct scatterlist *sg; 550 u8 *src; 551 552 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 553 sg = crypt_get_sg_data(cc, dmreq->sg_in); 554 src = kmap_local_page(sg_page(sg)); 555 crypt_iv_lmk_one(cc, iv, dmreq, src + sg->offset); 556 kunmap_local(src); 557 } else 558 memset(iv, 0, cc->iv_size); 559 return 0; 560 } 561 562 static void crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv, 563 struct dm_crypt_request *dmreq) 564 { 565 struct scatterlist *sg; 566 u8 *dst; 567 568 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) 569 return; 570 571 sg = crypt_get_sg_data(cc, dmreq->sg_out); 572 dst = kmap_local_page(sg_page(sg)); 573 crypt_iv_lmk_one(cc, iv, dmreq, dst + sg->offset); 574 575 /* Tweak the first block of plaintext sector */ 576 crypto_xor(dst + sg->offset, iv, cc->iv_size); 577 578 kunmap_local(dst); 579 } 580 581 static void crypt_iv_tcw_dtr(struct crypt_config *cc) 582 { 583 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 584 585 kfree_sensitive(tcw->iv_seed); 586 tcw->iv_seed = NULL; 587 kfree_sensitive(tcw->whitening); 588 tcw->whitening = NULL; 589 } 590 591 static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti, 592 const char *opts) 593 { 594 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 595 596 if (cc->sector_size != (1 << SECTOR_SHIFT)) { 597 ti->error = "Unsupported sector size for TCW"; 598 return -EINVAL; 599 } 600 601 if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) { 602 ti->error = "Wrong key size for TCW"; 603 return -EINVAL; 604 } 605 606 tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL); 607 tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL); 608 if (!tcw->iv_seed || !tcw->whitening) { 609 crypt_iv_tcw_dtr(cc); 610 ti->error = "Error allocating seed storage in TCW"; 611 return -ENOMEM; 612 } 613 614 return 0; 615 } 616 617 static int crypt_iv_tcw_init(struct crypt_config *cc) 618 { 619 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 620 int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE; 621 622 memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size); 623 memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size], 624 TCW_WHITENING_SIZE); 625 626 return 0; 627 } 628 629 static void crypt_iv_tcw_wipe(struct crypt_config *cc) 630 { 631 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 632 633 memset(tcw->iv_seed, 0, cc->iv_size); 634 memset(tcw->whitening, 0, TCW_WHITENING_SIZE); 635 } 636 637 static void crypt_iv_tcw_whitening(struct crypt_config *cc, 638 struct dm_crypt_request *dmreq, u8 *data) 639 { 640 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 641 __le64 sector = cpu_to_le64(dmreq->iv_sector); 642 u8 buf[TCW_WHITENING_SIZE]; 643 int i; 644 645 /* xor whitening with sector number */ 646 crypto_xor_cpy(buf, tcw->whitening, (u8 *)§or, 8); 647 crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)§or, 8); 648 649 /* calculate crc32 for every 32bit part and xor it */ 650 for (i = 0; i < 4; i++) 651 put_unaligned_le32(crc32(0, &buf[i * 4], 4), &buf[i * 4]); 652 crypto_xor(&buf[0], &buf[12], 4); 653 crypto_xor(&buf[4], &buf[8], 4); 654 655 /* apply whitening (8 bytes) to whole sector */ 656 for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++) 657 crypto_xor(data + i * 8, buf, 8); 658 memzero_explicit(buf, sizeof(buf)); 659 } 660 661 static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv, 662 struct dm_crypt_request *dmreq) 663 { 664 struct scatterlist *sg; 665 struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw; 666 __le64 sector = cpu_to_le64(dmreq->iv_sector); 667 u8 *src; 668 669 /* Remove whitening from ciphertext */ 670 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 671 sg = crypt_get_sg_data(cc, dmreq->sg_in); 672 src = kmap_local_page(sg_page(sg)); 673 crypt_iv_tcw_whitening(cc, dmreq, src + sg->offset); 674 kunmap_local(src); 675 } 676 677 /* Calculate IV */ 678 crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)§or, 8); 679 if (cc->iv_size > 8) 680 crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)§or, 681 cc->iv_size - 8); 682 683 return 0; 684 } 685 686 static void crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv, 687 struct dm_crypt_request *dmreq) 688 { 689 struct scatterlist *sg; 690 u8 *dst; 691 692 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 693 return; 694 695 /* Apply whitening on ciphertext */ 696 sg = crypt_get_sg_data(cc, dmreq->sg_out); 697 dst = kmap_local_page(sg_page(sg)); 698 crypt_iv_tcw_whitening(cc, dmreq, dst + sg->offset); 699 kunmap_local(dst); 700 } 701 702 static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv, 703 struct dm_crypt_request *dmreq) 704 { 705 /* Used only for writes, there must be an additional space to store IV */ 706 get_random_bytes(iv, cc->iv_size); 707 return 0; 708 } 709 710 static int crypt_iv_eboiv_ctr(struct crypt_config *cc, struct dm_target *ti, 711 const char *opts) 712 { 713 if (crypt_integrity_aead(cc)) { 714 ti->error = "AEAD transforms not supported for EBOIV"; 715 return -EINVAL; 716 } 717 718 if (crypto_skcipher_blocksize(any_tfm(cc)) != cc->iv_size) { 719 ti->error = "Block size of EBOIV cipher does not match IV size of block cipher"; 720 return -EINVAL; 721 } 722 723 return 0; 724 } 725 726 static int crypt_iv_eboiv_gen(struct crypt_config *cc, u8 *iv, 727 struct dm_crypt_request *dmreq) 728 { 729 struct crypto_skcipher *tfm = any_tfm(cc); 730 struct skcipher_request *req; 731 struct scatterlist src, dst; 732 DECLARE_CRYPTO_WAIT(wait); 733 unsigned int reqsize; 734 int err; 735 u8 *buf; 736 737 reqsize = sizeof(*req) + crypto_skcipher_reqsize(tfm); 738 reqsize = ALIGN(reqsize, __alignof__(__le64)); 739 740 req = kmalloc(reqsize + cc->iv_size, GFP_NOIO); 741 if (!req) 742 return -ENOMEM; 743 744 skcipher_request_set_tfm(req, tfm); 745 746 buf = (u8 *)req + reqsize; 747 memset(buf, 0, cc->iv_size); 748 *(__le64 *)buf = cpu_to_le64(dmreq->iv_sector * cc->sector_size); 749 750 sg_init_one(&src, page_address(ZERO_PAGE(0)), cc->iv_size); 751 sg_init_one(&dst, iv, cc->iv_size); 752 skcipher_request_set_crypt(req, &src, &dst, cc->iv_size, buf); 753 skcipher_request_set_callback(req, 0, crypto_req_done, &wait); 754 err = crypto_wait_req(crypto_skcipher_encrypt(req), &wait); 755 kfree_sensitive(req); 756 757 return err; 758 } 759 760 static void crypt_iv_elephant_dtr(struct crypt_config *cc) 761 { 762 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 763 764 kfree_sensitive(elephant->key); 765 elephant->key = NULL; 766 } 767 768 static int crypt_iv_elephant_ctr(struct crypt_config *cc, struct dm_target *ti, 769 const char *opts) 770 { 771 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 772 int r; 773 774 elephant->key = kmalloc_obj(*elephant->key); 775 if (!elephant->key) 776 return -ENOMEM; 777 778 r = crypt_iv_eboiv_ctr(cc, ti, NULL); 779 if (r) 780 crypt_iv_elephant_dtr(cc); 781 return r; 782 } 783 784 static void diffuser_disk_to_cpu(u32 *d, size_t n) 785 { 786 #ifndef __LITTLE_ENDIAN 787 int i; 788 789 for (i = 0; i < n; i++) 790 d[i] = le32_to_cpu((__le32)d[i]); 791 #endif 792 } 793 794 static void diffuser_cpu_to_disk(__le32 *d, size_t n) 795 { 796 #ifndef __LITTLE_ENDIAN 797 int i; 798 799 for (i = 0; i < n; i++) 800 d[i] = cpu_to_le32((u32)d[i]); 801 #endif 802 } 803 804 static void diffuser_a_decrypt(u32 *d, size_t n) 805 { 806 int i, i1, i2, i3; 807 808 for (i = 0; i < 5; i++) { 809 i1 = 0; 810 i2 = n - 2; 811 i3 = n - 5; 812 813 while (i1 < (n - 1)) { 814 d[i1] += d[i2] ^ (d[i3] << 9 | d[i3] >> 23); 815 i1++; i2++; i3++; 816 817 if (i3 >= n) 818 i3 -= n; 819 820 d[i1] += d[i2] ^ d[i3]; 821 i1++; i2++; i3++; 822 823 if (i2 >= n) 824 i2 -= n; 825 826 d[i1] += d[i2] ^ (d[i3] << 13 | d[i3] >> 19); 827 i1++; i2++; i3++; 828 829 d[i1] += d[i2] ^ d[i3]; 830 i1++; i2++; i3++; 831 } 832 } 833 } 834 835 static void diffuser_a_encrypt(u32 *d, size_t n) 836 { 837 int i, i1, i2, i3; 838 839 for (i = 0; i < 5; i++) { 840 i1 = n - 1; 841 i2 = n - 2 - 1; 842 i3 = n - 5 - 1; 843 844 while (i1 > 0) { 845 d[i1] -= d[i2] ^ d[i3]; 846 i1--; i2--; i3--; 847 848 d[i1] -= d[i2] ^ (d[i3] << 13 | d[i3] >> 19); 849 i1--; i2--; i3--; 850 851 if (i2 < 0) 852 i2 += n; 853 854 d[i1] -= d[i2] ^ d[i3]; 855 i1--; i2--; i3--; 856 857 if (i3 < 0) 858 i3 += n; 859 860 d[i1] -= d[i2] ^ (d[i3] << 9 | d[i3] >> 23); 861 i1--; i2--; i3--; 862 } 863 } 864 } 865 866 static void diffuser_b_decrypt(u32 *d, size_t n) 867 { 868 int i, i1, i2, i3; 869 870 for (i = 0; i < 3; i++) { 871 i1 = 0; 872 i2 = 2; 873 i3 = 5; 874 875 while (i1 < (n - 1)) { 876 d[i1] += d[i2] ^ d[i3]; 877 i1++; i2++; i3++; 878 879 d[i1] += d[i2] ^ (d[i3] << 10 | d[i3] >> 22); 880 i1++; i2++; i3++; 881 882 if (i2 >= n) 883 i2 -= n; 884 885 d[i1] += d[i2] ^ d[i3]; 886 i1++; i2++; i3++; 887 888 if (i3 >= n) 889 i3 -= n; 890 891 d[i1] += d[i2] ^ (d[i3] << 25 | d[i3] >> 7); 892 i1++; i2++; i3++; 893 } 894 } 895 } 896 897 static void diffuser_b_encrypt(u32 *d, size_t n) 898 { 899 int i, i1, i2, i3; 900 901 for (i = 0; i < 3; i++) { 902 i1 = n - 1; 903 i2 = 2 - 1; 904 i3 = 5 - 1; 905 906 while (i1 > 0) { 907 d[i1] -= d[i2] ^ (d[i3] << 25 | d[i3] >> 7); 908 i1--; i2--; i3--; 909 910 if (i3 < 0) 911 i3 += n; 912 913 d[i1] -= d[i2] ^ d[i3]; 914 i1--; i2--; i3--; 915 916 if (i2 < 0) 917 i2 += n; 918 919 d[i1] -= d[i2] ^ (d[i3] << 10 | d[i3] >> 22); 920 i1--; i2--; i3--; 921 922 d[i1] -= d[i2] ^ d[i3]; 923 i1--; i2--; i3--; 924 } 925 } 926 } 927 928 static void crypt_iv_elephant(struct crypt_config *cc, 929 struct dm_crypt_request *dmreq) 930 { 931 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 932 u8 *data, *data2, *data_offset; 933 struct scatterlist *sg, *sg2; 934 union { 935 __le64 w[2]; 936 u8 b[16]; 937 } es; 938 u8 ks[32] __aligned(__alignof(long)); /* Elephant sector key */ 939 int i; 940 941 es.w[0] = cpu_to_le64(dmreq->iv_sector * cc->sector_size); 942 es.w[1] = 0; 943 944 /* E(Ks, e(s)) */ 945 aes_encrypt(elephant->key, &ks[0], es.b); 946 947 /* E(Ks, e'(s)) */ 948 es.b[15] = 0x80; 949 aes_encrypt(elephant->key, &ks[16], es.b); 950 951 sg = crypt_get_sg_data(cc, dmreq->sg_out); 952 data = kmap_local_page(sg_page(sg)); 953 data_offset = data + sg->offset; 954 955 /* Cannot modify original bio, copy to sg_out and apply Elephant to it */ 956 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 957 sg2 = crypt_get_sg_data(cc, dmreq->sg_in); 958 data2 = kmap_local_page(sg_page(sg2)); 959 memcpy(data_offset, data2 + sg2->offset, cc->sector_size); 960 kunmap_local(data2); 961 } 962 963 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) { 964 diffuser_disk_to_cpu((u32 *)data_offset, cc->sector_size / sizeof(u32)); 965 diffuser_b_decrypt((u32 *)data_offset, cc->sector_size / sizeof(u32)); 966 diffuser_a_decrypt((u32 *)data_offset, cc->sector_size / sizeof(u32)); 967 diffuser_cpu_to_disk((__le32 *)data_offset, cc->sector_size / sizeof(u32)); 968 } 969 970 for (i = 0; i < (cc->sector_size / 32); i++) 971 crypto_xor(data_offset + i * 32, ks, 32); 972 973 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) { 974 diffuser_disk_to_cpu((u32 *)data_offset, cc->sector_size / sizeof(u32)); 975 diffuser_a_encrypt((u32 *)data_offset, cc->sector_size / sizeof(u32)); 976 diffuser_b_encrypt((u32 *)data_offset, cc->sector_size / sizeof(u32)); 977 diffuser_cpu_to_disk((__le32 *)data_offset, cc->sector_size / sizeof(u32)); 978 } 979 980 kunmap_local(data); 981 memzero_explicit(ks, sizeof(ks)); 982 memzero_explicit(&es, sizeof(es)); 983 } 984 985 static int crypt_iv_elephant_gen(struct crypt_config *cc, u8 *iv, 986 struct dm_crypt_request *dmreq) 987 { 988 if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) 989 crypt_iv_elephant(cc, dmreq); 990 991 return crypt_iv_eboiv_gen(cc, iv, dmreq); 992 } 993 994 static void crypt_iv_elephant_post(struct crypt_config *cc, u8 *iv, 995 struct dm_crypt_request *dmreq) 996 { 997 if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) 998 crypt_iv_elephant(cc, dmreq); 999 } 1000 1001 static int crypt_iv_elephant_init(struct crypt_config *cc) 1002 { 1003 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 1004 int key_offset = cc->key_size - cc->key_extra_size; 1005 1006 return aes_prepareenckey(elephant->key, &cc->key[key_offset], cc->key_extra_size); 1007 } 1008 1009 static void crypt_iv_elephant_wipe(struct crypt_config *cc) 1010 { 1011 struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant; 1012 1013 memzero_explicit(elephant->key, sizeof(*elephant->key)); 1014 } 1015 1016 static const struct crypt_iv_operations crypt_iv_plain_ops = { 1017 .generator = crypt_iv_plain_gen 1018 }; 1019 1020 static const struct crypt_iv_operations crypt_iv_plain64_ops = { 1021 .generator = crypt_iv_plain64_gen 1022 }; 1023 1024 static const struct crypt_iv_operations crypt_iv_plain64be_ops = { 1025 .generator = crypt_iv_plain64be_gen 1026 }; 1027 1028 static const struct crypt_iv_operations crypt_iv_essiv_ops = { 1029 .generator = crypt_iv_essiv_gen 1030 }; 1031 1032 static const struct crypt_iv_operations crypt_iv_benbi_ops = { 1033 .ctr = crypt_iv_benbi_ctr, 1034 .dtr = crypt_iv_benbi_dtr, 1035 .generator = crypt_iv_benbi_gen 1036 }; 1037 1038 static const struct crypt_iv_operations crypt_iv_null_ops = { 1039 .generator = crypt_iv_null_gen 1040 }; 1041 1042 static const struct crypt_iv_operations crypt_iv_lmk_ops = { 1043 .ctr = crypt_iv_lmk_ctr, 1044 .dtr = crypt_iv_lmk_dtr, 1045 .init = crypt_iv_lmk_init, 1046 .wipe = crypt_iv_lmk_wipe, 1047 .generator = crypt_iv_lmk_gen, 1048 .post = crypt_iv_lmk_post 1049 }; 1050 1051 static const struct crypt_iv_operations crypt_iv_tcw_ops = { 1052 .ctr = crypt_iv_tcw_ctr, 1053 .dtr = crypt_iv_tcw_dtr, 1054 .init = crypt_iv_tcw_init, 1055 .wipe = crypt_iv_tcw_wipe, 1056 .generator = crypt_iv_tcw_gen, 1057 .post = crypt_iv_tcw_post 1058 }; 1059 1060 static const struct crypt_iv_operations crypt_iv_random_ops = { 1061 .generator = crypt_iv_random_gen 1062 }; 1063 1064 static const struct crypt_iv_operations crypt_iv_eboiv_ops = { 1065 .ctr = crypt_iv_eboiv_ctr, 1066 .generator = crypt_iv_eboiv_gen 1067 }; 1068 1069 static const struct crypt_iv_operations crypt_iv_elephant_ops = { 1070 .ctr = crypt_iv_elephant_ctr, 1071 .dtr = crypt_iv_elephant_dtr, 1072 .init = crypt_iv_elephant_init, 1073 .wipe = crypt_iv_elephant_wipe, 1074 .generator = crypt_iv_elephant_gen, 1075 .post = crypt_iv_elephant_post 1076 }; 1077 1078 /* 1079 * Integrity extensions 1080 */ 1081 static bool crypt_integrity_aead(struct crypt_config *cc) 1082 { 1083 return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 1084 } 1085 1086 static bool crypt_integrity_hmac(struct crypt_config *cc) 1087 { 1088 return crypt_integrity_aead(cc) && cc->key_mac_size; 1089 } 1090 1091 /* Get sg containing data */ 1092 static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc, 1093 struct scatterlist *sg) 1094 { 1095 if (unlikely(crypt_integrity_aead(cc))) 1096 return &sg[2]; 1097 1098 return sg; 1099 } 1100 1101 static int dm_crypt_integrity_io_alloc(struct dm_crypt_io *io, struct bio *bio) 1102 { 1103 struct bio_integrity_payload *bip; 1104 unsigned int tag_len; 1105 int ret; 1106 1107 if (!bio_sectors(bio) || !io->cc->tuple_size) 1108 return 0; 1109 1110 bip = bio_integrity_alloc(bio, GFP_NOIO, 1); 1111 if (IS_ERR(bip)) 1112 return PTR_ERR(bip); 1113 1114 tag_len = io->cc->tuple_size * (bio_sectors(bio) >> io->cc->sector_shift); 1115 1116 bip->bip_iter.bi_sector = bio->bi_iter.bi_sector; 1117 1118 ret = bio_integrity_add_page(bio, virt_to_page(io->integrity_metadata), 1119 tag_len, offset_in_page(io->integrity_metadata)); 1120 if (unlikely(ret != tag_len)) 1121 return -ENOMEM; 1122 1123 return 0; 1124 } 1125 1126 static int crypt_integrity_ctr(struct crypt_config *cc, struct dm_target *ti) 1127 { 1128 #ifdef CONFIG_BLK_DEV_INTEGRITY 1129 struct blk_integrity *bi = blk_get_integrity(cc->dev->bdev->bd_disk); 1130 struct mapped_device *md = dm_table_get_md(ti->table); 1131 1132 /* We require an underlying device with non-PI metadata */ 1133 if (!bi || bi->csum_type != BLK_INTEGRITY_CSUM_NONE) { 1134 ti->error = "Integrity profile not supported."; 1135 return -EINVAL; 1136 } 1137 1138 if (bi->metadata_size < cc->used_tag_size) { 1139 ti->error = "Integrity profile tag size mismatch."; 1140 return -EINVAL; 1141 } 1142 cc->tuple_size = bi->metadata_size; 1143 if (1 << bi->interval_exp != cc->sector_size) { 1144 ti->error = "Integrity profile sector size mismatch."; 1145 return -EINVAL; 1146 } 1147 1148 if (crypt_integrity_aead(cc)) { 1149 cc->integrity_tag_size = cc->used_tag_size - cc->integrity_iv_size; 1150 DMDEBUG("%s: Integrity AEAD, tag size %u, IV size %u.", dm_device_name(md), 1151 cc->integrity_tag_size, cc->integrity_iv_size); 1152 1153 if (crypto_aead_setauthsize(any_tfm_aead(cc), cc->integrity_tag_size)) { 1154 ti->error = "Integrity AEAD auth tag size is not supported."; 1155 return -EINVAL; 1156 } 1157 } else if (cc->integrity_iv_size) 1158 DMDEBUG("%s: Additional per-sector space %u bytes for IV.", dm_device_name(md), 1159 cc->integrity_iv_size); 1160 1161 if ((cc->integrity_tag_size + cc->integrity_iv_size) > cc->tuple_size) { 1162 ti->error = "Not enough space for integrity tag in the profile."; 1163 return -EINVAL; 1164 } 1165 1166 return 0; 1167 #else 1168 ti->error = "Integrity profile not supported."; 1169 return -EINVAL; 1170 #endif 1171 } 1172 1173 static void crypt_convert_init(struct crypt_config *cc, 1174 struct convert_context *ctx, 1175 struct bio *bio_out, struct bio *bio_in, 1176 sector_t sector) 1177 { 1178 ctx->bio_in = bio_in; 1179 ctx->bio_out = bio_out; 1180 if (bio_in) 1181 ctx->iter_in = bio_in->bi_iter; 1182 if (bio_out) 1183 ctx->iter_out = bio_out->bi_iter; 1184 ctx->cc_sector = sector + cc->iv_offset; 1185 ctx->tag_offset = 0; 1186 init_completion(&ctx->restart); 1187 } 1188 1189 static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc, 1190 void *req) 1191 { 1192 return (struct dm_crypt_request *)((char *)req + cc->dmreq_start); 1193 } 1194 1195 static void *req_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq) 1196 { 1197 return (void *)((char *)dmreq - cc->dmreq_start); 1198 } 1199 1200 static u8 *iv_of_dmreq(struct crypt_config *cc, 1201 struct dm_crypt_request *dmreq) 1202 { 1203 if (crypt_integrity_aead(cc)) 1204 return (u8 *)ALIGN((unsigned long)(dmreq + 1), 1205 crypto_aead_alignmask(any_tfm_aead(cc)) + 1); 1206 else 1207 return (u8 *)ALIGN((unsigned long)(dmreq + 1), 1208 crypto_skcipher_alignmask(any_tfm(cc)) + 1); 1209 } 1210 1211 static u8 *org_iv_of_dmreq(struct crypt_config *cc, 1212 struct dm_crypt_request *dmreq) 1213 { 1214 return iv_of_dmreq(cc, dmreq) + cc->iv_size; 1215 } 1216 1217 static __le64 *org_sector_of_dmreq(struct crypt_config *cc, 1218 struct dm_crypt_request *dmreq) 1219 { 1220 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + cc->iv_size; 1221 1222 return (__le64 *) ptr; 1223 } 1224 1225 static unsigned int *org_tag_of_dmreq(struct crypt_config *cc, 1226 struct dm_crypt_request *dmreq) 1227 { 1228 u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + 1229 cc->iv_size + sizeof(uint64_t); 1230 1231 return (unsigned int *)ptr; 1232 } 1233 1234 static void *tag_from_dmreq(struct crypt_config *cc, 1235 struct dm_crypt_request *dmreq) 1236 { 1237 struct convert_context *ctx = dmreq->ctx; 1238 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 1239 1240 return &io->integrity_metadata[*org_tag_of_dmreq(cc, dmreq) * 1241 cc->tuple_size]; 1242 } 1243 1244 static void *iv_tag_from_dmreq(struct crypt_config *cc, 1245 struct dm_crypt_request *dmreq) 1246 { 1247 return tag_from_dmreq(cc, dmreq) + cc->integrity_tag_size; 1248 } 1249 1250 static int crypt_convert_block_aead(struct crypt_config *cc, 1251 struct convert_context *ctx, 1252 struct aead_request *req, 1253 unsigned int tag_offset) 1254 { 1255 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1256 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1257 struct dm_crypt_request *dmreq; 1258 u8 *iv, *org_iv, *tag_iv, *tag; 1259 __le64 *sector; 1260 int r = 0; 1261 1262 BUG_ON(cc->integrity_iv_size && cc->integrity_iv_size != cc->iv_size); 1263 1264 /* Reject unexpected unaligned bio. */ 1265 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1266 return -EIO; 1267 1268 dmreq = dmreq_of_req(cc, req); 1269 dmreq->iv_sector = ctx->cc_sector; 1270 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1271 dmreq->iv_sector >>= cc->sector_shift; 1272 dmreq->ctx = ctx; 1273 1274 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1275 1276 sector = org_sector_of_dmreq(cc, dmreq); 1277 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1278 1279 iv = iv_of_dmreq(cc, dmreq); 1280 org_iv = org_iv_of_dmreq(cc, dmreq); 1281 tag = tag_from_dmreq(cc, dmreq); 1282 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1283 1284 /* AEAD request: 1285 * |----- AAD -------|------ DATA -------|-- AUTH TAG --| 1286 * | (authenticated) | (auth+encryption) | | 1287 * | sector_LE | IV | sector in/out | tag in/out | 1288 */ 1289 sg_init_table(dmreq->sg_in, 4); 1290 sg_set_buf(&dmreq->sg_in[0], sector, sizeof(uint64_t)); 1291 sg_set_buf(&dmreq->sg_in[1], org_iv, cc->iv_size); 1292 sg_set_page(&dmreq->sg_in[2], bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1293 sg_set_buf(&dmreq->sg_in[3], tag, cc->integrity_tag_size); 1294 1295 sg_init_table(dmreq->sg_out, 4); 1296 sg_set_buf(&dmreq->sg_out[0], sector, sizeof(uint64_t)); 1297 sg_set_buf(&dmreq->sg_out[1], org_iv, cc->iv_size); 1298 sg_set_page(&dmreq->sg_out[2], bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1299 sg_set_buf(&dmreq->sg_out[3], tag, cc->integrity_tag_size); 1300 1301 if (cc->iv_gen_ops) { 1302 /* For READs use IV stored in integrity metadata */ 1303 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1304 memcpy(org_iv, tag_iv, cc->iv_size); 1305 } else { 1306 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1307 if (r < 0) 1308 return r; 1309 /* Store generated IV in integrity metadata */ 1310 if (cc->integrity_iv_size) 1311 memcpy(tag_iv, org_iv, cc->iv_size); 1312 } 1313 /* Working copy of IV, to be modified in crypto API */ 1314 memcpy(iv, org_iv, cc->iv_size); 1315 } 1316 1317 aead_request_set_ad(req, sizeof(uint64_t) + cc->iv_size); 1318 if (bio_data_dir(ctx->bio_in) == WRITE) { 1319 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out, 1320 cc->sector_size, iv); 1321 r = crypto_aead_encrypt(req); 1322 if (cc->integrity_tag_size + cc->integrity_iv_size != cc->tuple_size) 1323 memset(tag + cc->integrity_tag_size + cc->integrity_iv_size, 0, 1324 cc->tuple_size - (cc->integrity_tag_size + cc->integrity_iv_size)); 1325 } else { 1326 aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out, 1327 cc->sector_size + cc->integrity_tag_size, iv); 1328 r = crypto_aead_decrypt(req); 1329 } 1330 1331 if (r == -EBADMSG) { 1332 sector_t s = le64_to_cpu(*sector); 1333 1334 ctx->aead_failed = true; 1335 if (ctx->aead_recheck) { 1336 DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu", 1337 ctx->bio_in->bi_bdev, s); 1338 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead", 1339 ctx->bio_in, s, 0); 1340 } 1341 } 1342 1343 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1344 cc->iv_gen_ops->post(cc, org_iv, dmreq); 1345 1346 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1347 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1348 1349 return r; 1350 } 1351 1352 static int crypt_convert_block_skcipher(struct crypt_config *cc, 1353 struct convert_context *ctx, 1354 struct skcipher_request *req, 1355 unsigned int tag_offset) 1356 { 1357 struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in); 1358 struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out); 1359 struct scatterlist *sg_in, *sg_out; 1360 struct dm_crypt_request *dmreq; 1361 u8 *iv, *org_iv, *tag_iv; 1362 __le64 *sector; 1363 int r = 0; 1364 1365 /* Reject unexpected unaligned bio. */ 1366 if (unlikely(bv_in.bv_len & (cc->sector_size - 1))) 1367 return -EIO; 1368 1369 dmreq = dmreq_of_req(cc, req); 1370 dmreq->iv_sector = ctx->cc_sector; 1371 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 1372 dmreq->iv_sector >>= cc->sector_shift; 1373 dmreq->ctx = ctx; 1374 1375 *org_tag_of_dmreq(cc, dmreq) = tag_offset; 1376 1377 iv = iv_of_dmreq(cc, dmreq); 1378 org_iv = org_iv_of_dmreq(cc, dmreq); 1379 tag_iv = iv_tag_from_dmreq(cc, dmreq); 1380 1381 sector = org_sector_of_dmreq(cc, dmreq); 1382 *sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset); 1383 1384 /* For skcipher we use only the first sg item */ 1385 sg_in = &dmreq->sg_in[0]; 1386 sg_out = &dmreq->sg_out[0]; 1387 1388 sg_init_table(sg_in, 1); 1389 sg_set_page(sg_in, bv_in.bv_page, cc->sector_size, bv_in.bv_offset); 1390 1391 sg_init_table(sg_out, 1); 1392 sg_set_page(sg_out, bv_out.bv_page, cc->sector_size, bv_out.bv_offset); 1393 1394 if (cc->iv_gen_ops) { 1395 /* For READs use IV stored in integrity metadata */ 1396 if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) { 1397 memcpy(org_iv, tag_iv, cc->integrity_iv_size); 1398 } else { 1399 r = cc->iv_gen_ops->generator(cc, org_iv, dmreq); 1400 if (r < 0) 1401 return r; 1402 /* Data can be already preprocessed in generator */ 1403 if (test_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags)) 1404 sg_in = sg_out; 1405 /* Store generated IV in integrity metadata */ 1406 if (cc->integrity_iv_size) 1407 memcpy(tag_iv, org_iv, cc->integrity_iv_size); 1408 } 1409 /* Working copy of IV, to be modified in crypto API */ 1410 memcpy(iv, org_iv, cc->iv_size); 1411 } 1412 1413 skcipher_request_set_crypt(req, sg_in, sg_out, cc->sector_size, iv); 1414 1415 if (bio_data_dir(ctx->bio_in) == WRITE) 1416 r = crypto_skcipher_encrypt(req); 1417 else 1418 r = crypto_skcipher_decrypt(req); 1419 1420 if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post) 1421 cc->iv_gen_ops->post(cc, org_iv, dmreq); 1422 1423 bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size); 1424 bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size); 1425 1426 return r; 1427 } 1428 1429 static void kcryptd_async_done(void *async_req, int error); 1430 1431 static int crypt_alloc_req_skcipher(struct crypt_config *cc, 1432 struct convert_context *ctx) 1433 { 1434 unsigned int key_index = ctx->cc_sector & (cc->tfms_count - 1); 1435 1436 if (!ctx->r.req) { 1437 ctx->r.req = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1438 if (!ctx->r.req) 1439 return -ENOMEM; 1440 } 1441 1442 skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]); 1443 1444 /* 1445 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1446 * requests if driver request queue is full. 1447 */ 1448 skcipher_request_set_callback(ctx->r.req, 1449 CRYPTO_TFM_REQ_MAY_BACKLOG, 1450 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req)); 1451 1452 return 0; 1453 } 1454 1455 static int crypt_alloc_req_aead(struct crypt_config *cc, 1456 struct convert_context *ctx) 1457 { 1458 if (!ctx->r.req_aead) { 1459 ctx->r.req_aead = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO); 1460 if (!ctx->r.req_aead) 1461 return -ENOMEM; 1462 } 1463 1464 aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]); 1465 1466 /* 1467 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs 1468 * requests if driver request queue is full. 1469 */ 1470 aead_request_set_callback(ctx->r.req_aead, 1471 CRYPTO_TFM_REQ_MAY_BACKLOG, 1472 kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead)); 1473 1474 return 0; 1475 } 1476 1477 static int crypt_alloc_req(struct crypt_config *cc, 1478 struct convert_context *ctx) 1479 { 1480 if (crypt_integrity_aead(cc)) 1481 return crypt_alloc_req_aead(cc, ctx); 1482 else 1483 return crypt_alloc_req_skcipher(cc, ctx); 1484 } 1485 1486 static void crypt_free_req_skcipher(struct crypt_config *cc, 1487 struct skcipher_request *req, struct bio *base_bio) 1488 { 1489 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1490 1491 if ((struct skcipher_request *)(io + 1) != req) 1492 mempool_free(req, &cc->req_pool); 1493 } 1494 1495 static void crypt_free_req_aead(struct crypt_config *cc, 1496 struct aead_request *req, struct bio *base_bio) 1497 { 1498 struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size); 1499 1500 if ((struct aead_request *)(io + 1) != req) 1501 mempool_free(req, &cc->req_pool); 1502 } 1503 1504 static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio) 1505 { 1506 if (crypt_integrity_aead(cc)) 1507 crypt_free_req_aead(cc, req, base_bio); 1508 else 1509 crypt_free_req_skcipher(cc, req, base_bio); 1510 } 1511 1512 /* 1513 * Encrypt / decrypt data from one bio to another one (can be the same one) 1514 */ 1515 static blk_status_t crypt_convert(struct crypt_config *cc, 1516 struct convert_context *ctx, bool atomic, bool reset_pending) 1517 { 1518 unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT; 1519 int r; 1520 1521 /* 1522 * if reset_pending is set we are dealing with the bio for the first time, 1523 * else we're continuing to work on the previous bio, so don't mess with 1524 * the cc_pending counter 1525 */ 1526 if (reset_pending) 1527 atomic_set(&ctx->cc_pending, 1); 1528 1529 while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) { 1530 1531 r = crypt_alloc_req(cc, ctx); 1532 if (r) { 1533 complete(&ctx->restart); 1534 return BLK_STS_DEV_RESOURCE; 1535 } 1536 1537 atomic_inc(&ctx->cc_pending); 1538 1539 if (crypt_integrity_aead(cc)) 1540 r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, ctx->tag_offset); 1541 else 1542 r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, ctx->tag_offset); 1543 1544 switch (r) { 1545 /* 1546 * The request was queued by a crypto driver 1547 * but the driver request queue is full, let's wait. 1548 */ 1549 case -EBUSY: 1550 if (in_interrupt()) { 1551 if (try_wait_for_completion(&ctx->restart)) { 1552 /* 1553 * we don't have to block to wait for completion, 1554 * so proceed 1555 */ 1556 } else { 1557 /* 1558 * we can't wait for completion without blocking 1559 * exit and continue processing in a workqueue 1560 */ 1561 ctx->r.req = NULL; 1562 ctx->tag_offset++; 1563 ctx->cc_sector += sector_step; 1564 return BLK_STS_DEV_RESOURCE; 1565 } 1566 } else { 1567 wait_for_completion(&ctx->restart); 1568 } 1569 reinit_completion(&ctx->restart); 1570 fallthrough; 1571 /* 1572 * The request is queued and processed asynchronously, 1573 * completion function kcryptd_async_done() will be called. 1574 */ 1575 case -EINPROGRESS: 1576 ctx->r.req = NULL; 1577 ctx->tag_offset++; 1578 ctx->cc_sector += sector_step; 1579 continue; 1580 /* 1581 * The request was already processed (synchronously). 1582 */ 1583 case 0: 1584 atomic_dec(&ctx->cc_pending); 1585 ctx->cc_sector += sector_step; 1586 ctx->tag_offset++; 1587 if (!atomic) 1588 cond_resched(); 1589 continue; 1590 /* 1591 * There was a data integrity error. 1592 */ 1593 case -EBADMSG: 1594 atomic_dec(&ctx->cc_pending); 1595 return BLK_STS_PROTECTION; 1596 /* 1597 * There was an error while processing the request. 1598 */ 1599 default: 1600 atomic_dec(&ctx->cc_pending); 1601 return BLK_STS_IOERR; 1602 } 1603 } 1604 1605 return 0; 1606 } 1607 1608 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone); 1609 1610 /* 1611 * Generate a new unfragmented bio with the given size 1612 * This should never violate the device limitations (but if it did then block 1613 * core should split the bio as needed). 1614 * 1615 * This function may be called concurrently. If we allocate from the mempool 1616 * concurrently, there is a possibility of deadlock. For example, if we have 1617 * mempool of 256 pages, two processes, each wanting 256, pages allocate from 1618 * the mempool concurrently, it may deadlock in a situation where both processes 1619 * have allocated 128 pages and the mempool is exhausted. 1620 * 1621 * In order to avoid this scenario we allocate the pages under a mutex. 1622 * 1623 * In order to not degrade performance with excessive locking, we try 1624 * non-blocking allocations without a mutex first but on failure we fallback 1625 * to blocking allocations with a mutex. 1626 * 1627 * In order to reduce allocation overhead, we try to allocate compound pages in 1628 * the first pass. If they are not available, we fall back to the mempool. 1629 */ 1630 static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned int size) 1631 { 1632 struct crypt_config *cc = io->cc; 1633 struct bio *clone; 1634 unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT; 1635 gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM; 1636 unsigned int remaining_size; 1637 unsigned int order = MAX_PAGE_ORDER; 1638 1639 retry: 1640 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1641 mutex_lock(&cc->bio_alloc_lock); 1642 1643 clone = bio_alloc_bioset(cc->dev->bdev, nr_iovecs, io->base_bio->bi_opf, 1644 GFP_NOIO, &cc->bs); 1645 clone->bi_private = io; 1646 clone->bi_end_io = crypt_endio; 1647 clone->bi_ioprio = io->base_bio->bi_ioprio; 1648 clone->bi_iter.bi_sector = cc->start + io->sector; 1649 1650 remaining_size = size; 1651 1652 while (remaining_size) { 1653 struct page *pages; 1654 unsigned size_to_add; 1655 unsigned remaining_order = __fls((remaining_size + PAGE_SIZE - 1) >> PAGE_SHIFT); 1656 order = min(order, remaining_order); 1657 1658 while (order > 0) { 1659 if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) + 1660 (1 << order) > dm_crypt_pages_per_client)) 1661 goto decrease_order; 1662 pages = alloc_pages(gfp_mask 1663 | __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN | __GFP_COMP, 1664 order); 1665 if (likely(pages != NULL)) { 1666 percpu_counter_add(&cc->n_allocated_pages, 1 << order); 1667 goto have_pages; 1668 } 1669 decrease_order: 1670 order--; 1671 } 1672 1673 pages = mempool_alloc(&cc->page_pool, gfp_mask); 1674 if (!pages) { 1675 crypt_free_buffer_pages(cc, clone); 1676 bio_put(clone); 1677 gfp_mask |= __GFP_DIRECT_RECLAIM; 1678 order = 0; 1679 goto retry; 1680 } 1681 1682 have_pages: 1683 size_to_add = min((unsigned)PAGE_SIZE << order, remaining_size); 1684 __bio_add_page(clone, pages, size_to_add, 0); 1685 remaining_size -= size_to_add; 1686 } 1687 1688 /* Allocate space for integrity tags */ 1689 if (dm_crypt_integrity_io_alloc(io, clone)) { 1690 crypt_free_buffer_pages(cc, clone); 1691 bio_put(clone); 1692 clone = NULL; 1693 } 1694 1695 if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM)) 1696 mutex_unlock(&cc->bio_alloc_lock); 1697 1698 return clone; 1699 } 1700 1701 static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone) 1702 { 1703 struct folio_iter fi; 1704 1705 if (clone->bi_vcnt > 0) { /* bio_for_each_folio_all crashes with an empty bio */ 1706 bio_for_each_folio_all(fi, clone) { 1707 if (folio_test_large(fi.folio)) { 1708 percpu_counter_sub(&cc->n_allocated_pages, 1709 folio_nr_pages(fi.folio)); 1710 folio_put(fi.folio); 1711 } else { 1712 mempool_free(&fi.folio->page, &cc->page_pool); 1713 } 1714 } 1715 } 1716 } 1717 1718 static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc, 1719 struct bio *bio, sector_t sector) 1720 { 1721 io->cc = cc; 1722 io->base_bio = bio; 1723 io->sector = sector; 1724 io->error = 0; 1725 io->ctx.aead_recheck = false; 1726 io->ctx.aead_failed = false; 1727 io->ctx.r.req = NULL; 1728 io->integrity_metadata = NULL; 1729 io->integrity_metadata_from_pool = false; 1730 atomic_set(&io->io_pending, 0); 1731 } 1732 1733 static void crypt_inc_pending(struct dm_crypt_io *io) 1734 { 1735 atomic_inc(&io->io_pending); 1736 } 1737 1738 static void kcryptd_queue_read(struct dm_crypt_io *io); 1739 1740 /* 1741 * One of the bios was finished. Check for completion of 1742 * the whole request and correctly clean up the buffer. 1743 */ 1744 static void crypt_dec_pending(struct dm_crypt_io *io) 1745 { 1746 struct crypt_config *cc = io->cc; 1747 struct bio *base_bio = io->base_bio; 1748 blk_status_t error = io->error; 1749 1750 if (!atomic_dec_and_test(&io->io_pending)) 1751 return; 1752 1753 if (likely(!io->ctx.aead_recheck) && unlikely(io->ctx.aead_failed) && 1754 cc->used_tag_size && bio_data_dir(base_bio) == READ) { 1755 io->ctx.aead_recheck = true; 1756 io->ctx.aead_failed = false; 1757 io->error = 0; 1758 kcryptd_queue_read(io); 1759 return; 1760 } 1761 1762 if (io->ctx.r.req) 1763 crypt_free_req(cc, io->ctx.r.req, base_bio); 1764 1765 if (unlikely(io->integrity_metadata_from_pool)) 1766 mempool_free(io->integrity_metadata, &io->cc->tag_pool); 1767 else 1768 kfree(io->integrity_metadata); 1769 1770 base_bio->bi_status = error; 1771 1772 bio_endio(base_bio); 1773 } 1774 1775 /* 1776 * kcryptd/kcryptd_io: 1777 * 1778 * Needed because it would be very unwise to do decryption in an 1779 * interrupt context. 1780 * 1781 * kcryptd performs the actual encryption or decryption. 1782 * 1783 * kcryptd_io performs the IO submission. 1784 * 1785 * They must be separated as otherwise the final stages could be 1786 * starved by new requests which can block in the first stages due 1787 * to memory allocation. 1788 * 1789 * The work is done per CPU global for all dm-crypt instances. 1790 * They should not depend on each other and do not block. 1791 */ 1792 static void crypt_endio(struct bio *clone) 1793 { 1794 struct dm_crypt_io *io = clone->bi_private; 1795 struct crypt_config *cc = io->cc; 1796 unsigned int rw = bio_data_dir(clone); 1797 blk_status_t error = clone->bi_status; 1798 1799 if (io->ctx.aead_recheck && !error) { 1800 kcryptd_queue_crypt(io); 1801 return; 1802 } 1803 1804 /* 1805 * free the processed pages 1806 */ 1807 if (rw == WRITE || io->ctx.aead_recheck) 1808 crypt_free_buffer_pages(cc, clone); 1809 1810 bio_put(clone); 1811 1812 if (rw == READ && !error) { 1813 kcryptd_queue_crypt(io); 1814 return; 1815 } 1816 1817 if (unlikely(error)) 1818 io->error = error; 1819 1820 crypt_dec_pending(io); 1821 } 1822 1823 #define CRYPT_MAP_READ_GFP GFP_NOWAIT 1824 1825 static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp) 1826 { 1827 struct crypt_config *cc = io->cc; 1828 struct bio *clone; 1829 1830 if (io->ctx.aead_recheck) { 1831 if (!(gfp & __GFP_DIRECT_RECLAIM)) 1832 return 1; 1833 crypt_inc_pending(io); 1834 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size); 1835 if (unlikely(!clone)) { 1836 crypt_dec_pending(io); 1837 return 1; 1838 } 1839 crypt_convert_init(cc, &io->ctx, clone, clone, io->sector); 1840 io->saved_bi_iter = clone->bi_iter; 1841 dm_submit_bio_remap(io->base_bio, clone); 1842 return 0; 1843 } 1844 1845 /* 1846 * We need the original biovec array in order to decrypt the whole bio 1847 * data *afterwards* -- thanks to immutable biovecs we don't need to 1848 * worry about the block layer modifying the biovec array; so leverage 1849 * bio_alloc_clone(). 1850 */ 1851 clone = bio_alloc_clone(cc->dev->bdev, io->base_bio, gfp, &cc->bs); 1852 if (!clone) 1853 return 1; 1854 1855 clone->bi_iter.bi_sector = cc->start + io->sector; 1856 clone->bi_private = io; 1857 clone->bi_end_io = crypt_endio; 1858 1859 crypt_inc_pending(io); 1860 1861 if (dm_crypt_integrity_io_alloc(io, clone)) { 1862 crypt_dec_pending(io); 1863 bio_put(clone); 1864 return 1; 1865 } 1866 1867 dm_submit_bio_remap(io->base_bio, clone); 1868 return 0; 1869 } 1870 1871 static void kcryptd_io_read_work(struct work_struct *work) 1872 { 1873 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 1874 1875 crypt_inc_pending(io); 1876 if (kcryptd_io_read(io, GFP_NOIO)) 1877 io->error = BLK_STS_RESOURCE; 1878 crypt_dec_pending(io); 1879 } 1880 1881 static void kcryptd_queue_read(struct dm_crypt_io *io) 1882 { 1883 struct crypt_config *cc = io->cc; 1884 1885 INIT_WORK(&io->work, kcryptd_io_read_work); 1886 queue_work(cc->io_queue, &io->work); 1887 } 1888 1889 static void kcryptd_io_write(struct dm_crypt_io *io) 1890 { 1891 struct bio *clone = io->ctx.bio_out; 1892 1893 dm_submit_bio_remap(io->base_bio, clone); 1894 } 1895 1896 #define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node) 1897 1898 static int dmcrypt_write(void *data) 1899 { 1900 struct crypt_config *cc = data; 1901 struct dm_crypt_io *io; 1902 1903 while (1) { 1904 struct rb_root write_tree; 1905 struct blk_plug plug; 1906 1907 spin_lock_irq(&cc->write_thread_lock); 1908 continue_locked: 1909 1910 if (!RB_EMPTY_ROOT(&cc->write_tree)) 1911 goto pop_from_list; 1912 1913 set_current_state(TASK_INTERRUPTIBLE); 1914 1915 spin_unlock_irq(&cc->write_thread_lock); 1916 1917 if (unlikely(kthread_should_stop())) { 1918 set_current_state(TASK_RUNNING); 1919 break; 1920 } 1921 1922 schedule(); 1923 1924 spin_lock_irq(&cc->write_thread_lock); 1925 goto continue_locked; 1926 1927 pop_from_list: 1928 write_tree = cc->write_tree; 1929 cc->write_tree = RB_ROOT; 1930 spin_unlock_irq(&cc->write_thread_lock); 1931 1932 BUG_ON(rb_parent(write_tree.rb_node)); 1933 1934 /* 1935 * Note: we cannot walk the tree here with rb_next because 1936 * the structures may be freed when kcryptd_io_write is called. 1937 */ 1938 blk_start_plug(&plug); 1939 do { 1940 io = crypt_io_from_node(rb_first(&write_tree)); 1941 rb_erase(&io->rb_node, &write_tree); 1942 kcryptd_io_write(io); 1943 cond_resched(); 1944 } while (!RB_EMPTY_ROOT(&write_tree)); 1945 blk_finish_plug(&plug); 1946 } 1947 return 0; 1948 } 1949 1950 static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async) 1951 { 1952 struct bio *clone = io->ctx.bio_out; 1953 struct crypt_config *cc = io->cc; 1954 unsigned long flags; 1955 sector_t sector; 1956 struct rb_node **rbp, *parent; 1957 1958 if (unlikely(io->error)) { 1959 crypt_free_buffer_pages(cc, clone); 1960 bio_put(clone); 1961 crypt_dec_pending(io); 1962 return; 1963 } 1964 1965 /* crypt_convert should have filled the clone bio */ 1966 BUG_ON(io->ctx.iter_out.bi_size); 1967 1968 if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) || 1969 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) { 1970 dm_submit_bio_remap(io->base_bio, clone); 1971 return; 1972 } 1973 1974 spin_lock_irqsave(&cc->write_thread_lock, flags); 1975 if (RB_EMPTY_ROOT(&cc->write_tree)) 1976 wake_up_process(cc->write_thread); 1977 rbp = &cc->write_tree.rb_node; 1978 parent = NULL; 1979 sector = io->sector; 1980 while (*rbp) { 1981 parent = *rbp; 1982 if (sector < crypt_io_from_node(parent)->sector) 1983 rbp = &(*rbp)->rb_left; 1984 else 1985 rbp = &(*rbp)->rb_right; 1986 } 1987 rb_link_node(&io->rb_node, parent, rbp); 1988 rb_insert_color(&io->rb_node, &cc->write_tree); 1989 spin_unlock_irqrestore(&cc->write_thread_lock, flags); 1990 } 1991 1992 static bool kcryptd_crypt_write_inline(struct crypt_config *cc, 1993 struct convert_context *ctx) 1994 1995 { 1996 if (!test_bit(DM_CRYPT_WRITE_INLINE, &cc->flags)) 1997 return false; 1998 1999 /* 2000 * Note: zone append writes (REQ_OP_ZONE_APPEND) do not have ordering 2001 * constraints so they do not need to be issued inline by 2002 * kcryptd_crypt_write_convert(). 2003 */ 2004 switch (bio_op(ctx->bio_in)) { 2005 case REQ_OP_WRITE: 2006 case REQ_OP_WRITE_ZEROES: 2007 return true; 2008 default: 2009 return false; 2010 } 2011 } 2012 2013 static void kcryptd_crypt_write_continue(struct work_struct *work) 2014 { 2015 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2016 struct crypt_config *cc = io->cc; 2017 struct convert_context *ctx = &io->ctx; 2018 int crypt_finished; 2019 blk_status_t r; 2020 2021 wait_for_completion(&ctx->restart); 2022 reinit_completion(&ctx->restart); 2023 2024 r = crypt_convert(cc, &io->ctx, false, false); 2025 if (r) 2026 io->error = r; 2027 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2028 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2029 /* Wait for completion signaled by kcryptd_async_done() */ 2030 wait_for_completion(&ctx->restart); 2031 crypt_finished = 1; 2032 } 2033 2034 /* Encryption was already finished, submit io now */ 2035 if (crypt_finished) 2036 kcryptd_crypt_write_io_submit(io, 0); 2037 2038 crypt_dec_pending(io); 2039 } 2040 2041 static void kcryptd_crypt_write_convert(struct dm_crypt_io *io) 2042 { 2043 struct crypt_config *cc = io->cc; 2044 struct convert_context *ctx = &io->ctx; 2045 struct bio *clone; 2046 int crypt_finished; 2047 blk_status_t r; 2048 2049 /* 2050 * Prevent io from disappearing until this function completes. 2051 */ 2052 crypt_inc_pending(io); 2053 crypt_convert_init(cc, ctx, NULL, io->base_bio, io->sector); 2054 2055 clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size); 2056 if (unlikely(!clone)) { 2057 io->error = BLK_STS_IOERR; 2058 goto dec; 2059 } 2060 2061 io->ctx.bio_out = clone; 2062 io->ctx.iter_out = clone->bi_iter; 2063 2064 if (crypt_integrity_aead(cc)) { 2065 bio_copy_data(clone, io->base_bio); 2066 io->ctx.bio_in = clone; 2067 io->ctx.iter_in = clone->bi_iter; 2068 } 2069 2070 crypt_inc_pending(io); 2071 r = crypt_convert(cc, ctx, 2072 test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags), true); 2073 /* 2074 * Crypto API backlogged the request, because its queue was full 2075 * and we're in softirq context, so continue from a workqueue 2076 * (TODO: is it actually possible to be in softirq in the write path?) 2077 */ 2078 if (r == BLK_STS_DEV_RESOURCE) { 2079 INIT_WORK(&io->work, kcryptd_crypt_write_continue); 2080 queue_work(cc->crypt_queue, &io->work); 2081 return; 2082 } 2083 if (r) 2084 io->error = r; 2085 crypt_finished = atomic_dec_and_test(&ctx->cc_pending); 2086 if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) { 2087 /* Wait for completion signaled by kcryptd_async_done() */ 2088 wait_for_completion(&ctx->restart); 2089 crypt_finished = 1; 2090 } 2091 2092 /* Encryption was already finished, submit io now */ 2093 if (crypt_finished) 2094 kcryptd_crypt_write_io_submit(io, 0); 2095 2096 dec: 2097 crypt_dec_pending(io); 2098 } 2099 2100 static void kcryptd_crypt_read_done(struct dm_crypt_io *io) 2101 { 2102 if (io->ctx.aead_recheck) { 2103 if (!io->error) { 2104 io->ctx.bio_in->bi_iter = io->saved_bi_iter; 2105 bio_copy_data(io->base_bio, io->ctx.bio_in); 2106 } 2107 crypt_free_buffer_pages(io->cc, io->ctx.bio_in); 2108 bio_put(io->ctx.bio_in); 2109 } 2110 crypt_dec_pending(io); 2111 } 2112 2113 static void kcryptd_crypt_read_continue(struct work_struct *work) 2114 { 2115 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2116 struct crypt_config *cc = io->cc; 2117 blk_status_t r; 2118 2119 wait_for_completion(&io->ctx.restart); 2120 reinit_completion(&io->ctx.restart); 2121 2122 r = crypt_convert(cc, &io->ctx, false, false); 2123 if (r) 2124 io->error = r; 2125 2126 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2127 kcryptd_crypt_read_done(io); 2128 2129 crypt_dec_pending(io); 2130 } 2131 2132 static void kcryptd_crypt_read_convert(struct dm_crypt_io *io) 2133 { 2134 struct crypt_config *cc = io->cc; 2135 blk_status_t r; 2136 2137 crypt_inc_pending(io); 2138 2139 if (io->ctx.aead_recheck) { 2140 r = crypt_convert(cc, &io->ctx, 2141 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true); 2142 } else { 2143 crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio, 2144 io->sector); 2145 2146 r = crypt_convert(cc, &io->ctx, 2147 test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true); 2148 } 2149 /* 2150 * Crypto API backlogged the request, because its queue was full 2151 * and we're in softirq context, so continue from a workqueue 2152 */ 2153 if (r == BLK_STS_DEV_RESOURCE) { 2154 INIT_WORK(&io->work, kcryptd_crypt_read_continue); 2155 queue_work(cc->crypt_queue, &io->work); 2156 return; 2157 } 2158 if (r) 2159 io->error = r; 2160 2161 if (atomic_dec_and_test(&io->ctx.cc_pending)) 2162 kcryptd_crypt_read_done(io); 2163 2164 crypt_dec_pending(io); 2165 } 2166 2167 static void kcryptd_async_done(void *data, int error) 2168 { 2169 struct dm_crypt_request *dmreq = data; 2170 struct convert_context *ctx = dmreq->ctx; 2171 struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx); 2172 struct crypt_config *cc = io->cc; 2173 2174 /* 2175 * A request from crypto driver backlog is going to be processed now, 2176 * finish the completion and continue in crypt_convert(). 2177 * (Callback will be called for the second time for this request.) 2178 */ 2179 if (error == -EINPROGRESS) { 2180 complete(&ctx->restart); 2181 return; 2182 } 2183 2184 if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post) 2185 cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq); 2186 2187 if (error == -EBADMSG) { 2188 sector_t s = le64_to_cpu(*org_sector_of_dmreq(cc, dmreq)); 2189 2190 ctx->aead_failed = true; 2191 if (ctx->aead_recheck) { 2192 DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu", 2193 ctx->bio_in->bi_bdev, s); 2194 dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead", 2195 ctx->bio_in, s, 0); 2196 } 2197 io->error = BLK_STS_PROTECTION; 2198 } else if (error < 0) 2199 io->error = BLK_STS_IOERR; 2200 2201 crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio); 2202 2203 if (!atomic_dec_and_test(&ctx->cc_pending)) 2204 return; 2205 2206 /* 2207 * The request is fully completed: for inline writes, let 2208 * kcryptd_crypt_write_convert() do the IO submission. 2209 */ 2210 if (bio_data_dir(io->base_bio) == READ) { 2211 kcryptd_crypt_read_done(io); 2212 return; 2213 } 2214 2215 if (kcryptd_crypt_write_inline(cc, ctx)) { 2216 complete(&ctx->restart); 2217 return; 2218 } 2219 2220 kcryptd_crypt_write_io_submit(io, 1); 2221 } 2222 2223 static void kcryptd_crypt(struct work_struct *work) 2224 { 2225 struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work); 2226 2227 if (bio_data_dir(io->base_bio) == READ) 2228 kcryptd_crypt_read_convert(io); 2229 else 2230 kcryptd_crypt_write_convert(io); 2231 } 2232 2233 static void kcryptd_queue_crypt(struct dm_crypt_io *io) 2234 { 2235 struct crypt_config *cc = io->cc; 2236 2237 if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) || 2238 (bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) { 2239 /* 2240 * in_hardirq(): Crypto API's skcipher_walk_first() refuses to work in hard IRQ context. 2241 * irqs_disabled(): the kernel may run some IO completion from the idle thread, but 2242 * it is being executed with irqs disabled. 2243 */ 2244 if (in_hardirq() || irqs_disabled()) { 2245 INIT_WORK(&io->work, kcryptd_crypt); 2246 queue_work(system_bh_wq, &io->work); 2247 return; 2248 } else { 2249 kcryptd_crypt(&io->work); 2250 return; 2251 } 2252 } 2253 2254 INIT_WORK(&io->work, kcryptd_crypt); 2255 queue_work(cc->crypt_queue, &io->work); 2256 } 2257 2258 static void crypt_free_tfms_aead(struct crypt_config *cc) 2259 { 2260 if (!cc->cipher_tfm.tfms_aead) 2261 return; 2262 2263 if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2264 crypto_free_aead(cc->cipher_tfm.tfms_aead[0]); 2265 cc->cipher_tfm.tfms_aead[0] = NULL; 2266 } 2267 2268 kfree(cc->cipher_tfm.tfms_aead); 2269 cc->cipher_tfm.tfms_aead = NULL; 2270 } 2271 2272 static void crypt_free_tfms_skcipher(struct crypt_config *cc) 2273 { 2274 unsigned int i; 2275 2276 if (!cc->cipher_tfm.tfms) 2277 return; 2278 2279 for (i = 0; i < cc->tfms_count; i++) 2280 if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) { 2281 crypto_free_skcipher(cc->cipher_tfm.tfms[i]); 2282 cc->cipher_tfm.tfms[i] = NULL; 2283 } 2284 2285 kfree(cc->cipher_tfm.tfms); 2286 cc->cipher_tfm.tfms = NULL; 2287 } 2288 2289 static void crypt_free_tfms(struct crypt_config *cc) 2290 { 2291 if (crypt_integrity_aead(cc)) 2292 crypt_free_tfms_aead(cc); 2293 else 2294 crypt_free_tfms_skcipher(cc); 2295 } 2296 2297 static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode) 2298 { 2299 unsigned int i; 2300 int err; 2301 2302 cc->cipher_tfm.tfms = kzalloc_objs(struct crypto_skcipher *, 2303 cc->tfms_count); 2304 if (!cc->cipher_tfm.tfms) 2305 return -ENOMEM; 2306 2307 for (i = 0; i < cc->tfms_count; i++) { 2308 cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0, 2309 CRYPTO_ALG_ALLOCATES_MEMORY); 2310 if (IS_ERR(cc->cipher_tfm.tfms[i])) { 2311 err = PTR_ERR(cc->cipher_tfm.tfms[i]); 2312 crypt_free_tfms(cc); 2313 return err; 2314 } 2315 } 2316 2317 /* 2318 * dm-crypt performance can vary greatly depending on which crypto 2319 * algorithm implementation is used. Help people debug performance 2320 * problems by logging the ->cra_driver_name. 2321 */ 2322 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2323 crypto_skcipher_alg(any_tfm(cc))->base.cra_driver_name); 2324 return 0; 2325 } 2326 2327 static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode) 2328 { 2329 int err; 2330 2331 cc->cipher_tfm.tfms = kmalloc_obj(struct crypto_skcipher *); 2332 if (!cc->cipher_tfm.tfms) 2333 return -ENOMEM; 2334 2335 cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0, 2336 CRYPTO_ALG_ALLOCATES_MEMORY); 2337 if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) { 2338 err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]); 2339 crypt_free_tfms(cc); 2340 return err; 2341 } 2342 2343 DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode, 2344 crypto_aead_alg(any_tfm_aead(cc))->base.cra_driver_name); 2345 return 0; 2346 } 2347 2348 static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode) 2349 { 2350 if (crypt_integrity_aead(cc)) 2351 return crypt_alloc_tfms_aead(cc, ciphermode); 2352 else 2353 return crypt_alloc_tfms_skcipher(cc, ciphermode); 2354 } 2355 2356 static unsigned int crypt_subkey_size(struct crypt_config *cc) 2357 { 2358 return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count); 2359 } 2360 2361 static unsigned int crypt_authenckey_size(struct crypt_config *cc) 2362 { 2363 return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param)); 2364 } 2365 2366 /* 2367 * If AEAD is composed like authenc(hmac(sha256),xts(aes)), 2368 * the key must be for some reason in special format. 2369 * This funcion converts cc->key to this special format. 2370 */ 2371 static void crypt_copy_authenckey(char *p, const void *key, 2372 unsigned int enckeylen, unsigned int authkeylen) 2373 { 2374 struct crypto_authenc_key_param *param; 2375 struct rtattr *rta; 2376 2377 rta = (struct rtattr *)p; 2378 param = RTA_DATA(rta); 2379 param->enckeylen = cpu_to_be32(enckeylen); 2380 rta->rta_len = RTA_LENGTH(sizeof(*param)); 2381 rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; 2382 p += RTA_SPACE(sizeof(*param)); 2383 memcpy(p, key + enckeylen, authkeylen); 2384 p += authkeylen; 2385 memcpy(p, key, enckeylen); 2386 } 2387 2388 static int crypt_setkey(struct crypt_config *cc) 2389 { 2390 unsigned int subkey_size; 2391 int err = 0, i, r; 2392 2393 /* Ignore extra keys (which are used for IV etc) */ 2394 subkey_size = crypt_subkey_size(cc); 2395 2396 if (crypt_integrity_hmac(cc)) { 2397 if (subkey_size < cc->key_mac_size) 2398 return -EINVAL; 2399 2400 crypt_copy_authenckey(cc->authenc_key, cc->key, 2401 subkey_size - cc->key_mac_size, 2402 cc->key_mac_size); 2403 } 2404 2405 for (i = 0; i < cc->tfms_count; i++) { 2406 if (crypt_integrity_hmac(cc)) 2407 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2408 cc->authenc_key, crypt_authenckey_size(cc)); 2409 else if (crypt_integrity_aead(cc)) 2410 r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i], 2411 cc->key + (i * subkey_size), 2412 subkey_size); 2413 else 2414 r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i], 2415 cc->key + (i * subkey_size), 2416 subkey_size); 2417 if (r) 2418 err = r; 2419 } 2420 2421 if (crypt_integrity_hmac(cc)) 2422 memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc)); 2423 2424 return err; 2425 } 2426 2427 #ifdef CONFIG_KEYS 2428 2429 static bool contains_whitespace(const char *str) 2430 { 2431 while (*str) 2432 if (isspace(*str++)) 2433 return true; 2434 return false; 2435 } 2436 2437 static int set_key_user(struct crypt_config *cc, struct key *key) 2438 { 2439 const struct user_key_payload *ukp; 2440 2441 ukp = user_key_payload_locked(key); 2442 if (!ukp) 2443 return -EKEYREVOKED; 2444 2445 if (cc->key_size != ukp->datalen) 2446 return -EINVAL; 2447 2448 memcpy(cc->key, ukp->data, cc->key_size); 2449 2450 return 0; 2451 } 2452 2453 static int set_key_encrypted(struct crypt_config *cc, struct key *key) 2454 { 2455 const struct encrypted_key_payload *ekp; 2456 2457 ekp = key->payload.data[0]; 2458 if (!ekp) 2459 return -EKEYREVOKED; 2460 2461 if (cc->key_size != ekp->decrypted_datalen) 2462 return -EINVAL; 2463 2464 memcpy(cc->key, ekp->decrypted_data, cc->key_size); 2465 2466 return 0; 2467 } 2468 2469 static int set_key_trusted(struct crypt_config *cc, struct key *key) 2470 { 2471 const struct trusted_key_payload *tkp; 2472 2473 tkp = key->payload.data[0]; 2474 if (!tkp) 2475 return -EKEYREVOKED; 2476 2477 if (cc->key_size != tkp->key_len) 2478 return -EINVAL; 2479 2480 memcpy(cc->key, tkp->key, cc->key_size); 2481 2482 return 0; 2483 } 2484 2485 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2486 { 2487 char *new_key_string, *key_desc; 2488 int ret; 2489 struct key_type *type; 2490 struct key *key; 2491 int (*set_key)(struct crypt_config *cc, struct key *key); 2492 2493 /* 2494 * Reject key_string with whitespace. dm core currently lacks code for 2495 * proper whitespace escaping in arguments on DM_TABLE_STATUS path. 2496 */ 2497 if (contains_whitespace(key_string)) { 2498 DMERR("whitespace chars not allowed in key string"); 2499 return -EINVAL; 2500 } 2501 2502 /* look for next ':' separating key_type from key_description */ 2503 key_desc = strchr(key_string, ':'); 2504 if (!key_desc || key_desc == key_string || !strlen(key_desc + 1)) 2505 return -EINVAL; 2506 2507 if (!strncmp(key_string, "logon:", key_desc - key_string + 1)) { 2508 type = &key_type_logon; 2509 set_key = set_key_user; 2510 } else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) { 2511 type = &key_type_user; 2512 set_key = set_key_user; 2513 } else if (IS_ENABLED(CONFIG_ENCRYPTED_KEYS) && 2514 !strncmp(key_string, "encrypted:", key_desc - key_string + 1)) { 2515 type = &key_type_encrypted; 2516 set_key = set_key_encrypted; 2517 } else if (IS_ENABLED(CONFIG_TRUSTED_KEYS) && 2518 !strncmp(key_string, "trusted:", key_desc - key_string + 1)) { 2519 type = &key_type_trusted; 2520 set_key = set_key_trusted; 2521 } else { 2522 return -EINVAL; 2523 } 2524 2525 new_key_string = kstrdup(key_string, GFP_KERNEL); 2526 if (!new_key_string) 2527 return -ENOMEM; 2528 2529 key = request_key(type, key_desc + 1, NULL); 2530 if (IS_ERR(key)) { 2531 ret = PTR_ERR(key); 2532 goto free_new_key_string; 2533 } 2534 2535 down_read(&key->sem); 2536 ret = set_key(cc, key); 2537 up_read(&key->sem); 2538 key_put(key); 2539 if (ret < 0) 2540 goto free_new_key_string; 2541 2542 /* clear the flag since following operations may invalidate previously valid key */ 2543 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2544 2545 ret = crypt_setkey(cc); 2546 if (ret) 2547 goto free_new_key_string; 2548 2549 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2550 kfree_sensitive(cc->key_string); 2551 cc->key_string = new_key_string; 2552 return 0; 2553 2554 free_new_key_string: 2555 kfree_sensitive(new_key_string); 2556 return ret; 2557 } 2558 2559 static int get_key_size(char **key_string) 2560 { 2561 char *colon, dummy; 2562 int ret; 2563 2564 if (*key_string[0] != ':') 2565 return strlen(*key_string) >> 1; 2566 2567 /* look for next ':' in key string */ 2568 colon = strpbrk(*key_string + 1, ":"); 2569 if (!colon) 2570 return -EINVAL; 2571 2572 if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':') 2573 return -EINVAL; 2574 2575 *key_string = colon; 2576 2577 /* remaining key string should be :<logon|user>:<key_desc> */ 2578 2579 return ret; 2580 } 2581 2582 #else 2583 2584 static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string) 2585 { 2586 return -EINVAL; 2587 } 2588 2589 static int get_key_size(char **key_string) 2590 { 2591 return (*key_string[0] == ':') ? -EINVAL : (int)(strlen(*key_string) >> 1); 2592 } 2593 2594 #endif /* CONFIG_KEYS */ 2595 2596 static int crypt_set_key(struct crypt_config *cc, char *key) 2597 { 2598 int r = -EINVAL; 2599 int key_string_len = strlen(key); 2600 2601 /* Hyphen (which gives a key_size of zero) means there is no key. */ 2602 if (!cc->key_size && strcmp(key, "-")) 2603 goto out; 2604 2605 /* ':' means the key is in kernel keyring, short-circuit normal key processing */ 2606 if (key[0] == ':') { 2607 r = crypt_set_keyring_key(cc, key + 1); 2608 goto out; 2609 } 2610 2611 /* clear the flag since following operations may invalidate previously valid key */ 2612 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2613 2614 /* wipe references to any kernel keyring key */ 2615 kfree_sensitive(cc->key_string); 2616 cc->key_string = NULL; 2617 2618 /* Decode key from its hex representation. */ 2619 if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0) 2620 goto out; 2621 2622 r = crypt_setkey(cc); 2623 if (!r) 2624 set_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2625 2626 out: 2627 /* Hex key string not needed after here, so wipe it. */ 2628 memset(key, '0', key_string_len); 2629 2630 return r; 2631 } 2632 2633 static int crypt_wipe_key(struct crypt_config *cc) 2634 { 2635 int r; 2636 2637 clear_bit(DM_CRYPT_KEY_VALID, &cc->flags); 2638 get_random_bytes(&cc->key, cc->key_size); 2639 2640 /* Wipe IV private keys */ 2641 if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) 2642 cc->iv_gen_ops->wipe(cc); 2643 2644 kfree_sensitive(cc->key_string); 2645 cc->key_string = NULL; 2646 r = crypt_setkey(cc); 2647 memset(&cc->key, 0, cc->key_size * sizeof(u8)); 2648 2649 return r; 2650 } 2651 2652 static void crypt_calculate_pages_per_client(void) 2653 { 2654 unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100; 2655 2656 if (!dm_crypt_clients_n) 2657 return; 2658 2659 pages /= dm_crypt_clients_n; 2660 if (pages < DM_CRYPT_MIN_PAGES_PER_CLIENT) 2661 pages = DM_CRYPT_MIN_PAGES_PER_CLIENT; 2662 dm_crypt_pages_per_client = pages; 2663 } 2664 2665 static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data) 2666 { 2667 struct crypt_config *cc = pool_data; 2668 struct page *page; 2669 2670 /* 2671 * Note, percpu_counter_read_positive() may over (and under) estimate 2672 * the current usage by at most (batch - 1) * num_online_cpus() pages, 2673 * but avoids potential spinlock contention of an exact result. 2674 */ 2675 if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) >= dm_crypt_pages_per_client) && 2676 likely(gfp_mask & __GFP_NORETRY)) 2677 return NULL; 2678 2679 page = alloc_page(gfp_mask); 2680 if (likely(page != NULL)) 2681 percpu_counter_add(&cc->n_allocated_pages, 1); 2682 2683 return page; 2684 } 2685 2686 static void crypt_page_free(void *page, void *pool_data) 2687 { 2688 struct crypt_config *cc = pool_data; 2689 2690 __free_page(page); 2691 percpu_counter_sub(&cc->n_allocated_pages, 1); 2692 } 2693 2694 static void crypt_dtr(struct dm_target *ti) 2695 { 2696 struct crypt_config *cc = ti->private; 2697 2698 ti->private = NULL; 2699 2700 if (!cc) 2701 return; 2702 2703 if (cc->write_thread) 2704 kthread_stop(cc->write_thread); 2705 2706 if (cc->io_queue) 2707 destroy_workqueue(cc->io_queue); 2708 if (cc->crypt_queue) 2709 destroy_workqueue(cc->crypt_queue); 2710 2711 if (cc->workqueue_id) 2712 ida_free(&workqueue_ida, cc->workqueue_id); 2713 2714 crypt_free_tfms(cc); 2715 2716 bioset_exit(&cc->bs); 2717 2718 mempool_exit(&cc->page_pool); 2719 mempool_exit(&cc->req_pool); 2720 mempool_exit(&cc->tag_pool); 2721 2722 WARN_ON(percpu_counter_sum(&cc->n_allocated_pages) != 0); 2723 percpu_counter_destroy(&cc->n_allocated_pages); 2724 2725 if (cc->iv_gen_ops && cc->iv_gen_ops->dtr) 2726 cc->iv_gen_ops->dtr(cc); 2727 2728 if (cc->dev) 2729 dm_put_device(ti, cc->dev); 2730 2731 kfree_sensitive(cc->cipher_string); 2732 kfree_sensitive(cc->key_string); 2733 kfree_sensitive(cc->cipher_auth); 2734 kfree_sensitive(cc->authenc_key); 2735 2736 mutex_destroy(&cc->bio_alloc_lock); 2737 2738 /* Must zero key material before freeing */ 2739 kfree_sensitive(cc); 2740 2741 spin_lock(&dm_crypt_clients_lock); 2742 WARN_ON(!dm_crypt_clients_n); 2743 dm_crypt_clients_n--; 2744 crypt_calculate_pages_per_client(); 2745 spin_unlock(&dm_crypt_clients_lock); 2746 2747 dm_audit_log_dtr(DM_MSG_PREFIX, ti, 1); 2748 } 2749 2750 static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode) 2751 { 2752 struct crypt_config *cc = ti->private; 2753 2754 if (crypt_integrity_aead(cc)) 2755 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2756 else 2757 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2758 2759 if (cc->iv_size) 2760 /* at least a 64 bit sector number should fit in our buffer */ 2761 cc->iv_size = max(cc->iv_size, 2762 (unsigned int)(sizeof(u64) / sizeof(u8))); 2763 else if (ivmode) { 2764 DMWARN("Selected cipher does not support IVs"); 2765 ivmode = NULL; 2766 } 2767 2768 /* Choose ivmode, see comments at iv code. */ 2769 if (ivmode == NULL) 2770 cc->iv_gen_ops = NULL; 2771 else if (strcmp(ivmode, "plain") == 0) 2772 cc->iv_gen_ops = &crypt_iv_plain_ops; 2773 else if (strcmp(ivmode, "plain64") == 0) 2774 cc->iv_gen_ops = &crypt_iv_plain64_ops; 2775 else if (strcmp(ivmode, "plain64be") == 0) 2776 cc->iv_gen_ops = &crypt_iv_plain64be_ops; 2777 else if (strcmp(ivmode, "essiv") == 0) 2778 cc->iv_gen_ops = &crypt_iv_essiv_ops; 2779 else if (strcmp(ivmode, "benbi") == 0) 2780 cc->iv_gen_ops = &crypt_iv_benbi_ops; 2781 else if (strcmp(ivmode, "null") == 0) 2782 cc->iv_gen_ops = &crypt_iv_null_ops; 2783 else if (strcmp(ivmode, "eboiv") == 0) 2784 cc->iv_gen_ops = &crypt_iv_eboiv_ops; 2785 else if (strcmp(ivmode, "elephant") == 0) { 2786 cc->iv_gen_ops = &crypt_iv_elephant_ops; 2787 cc->key_parts = 2; 2788 cc->key_extra_size = cc->key_size / 2; 2789 if (cc->key_extra_size > ELEPHANT_MAX_KEY_SIZE) 2790 return -EINVAL; 2791 set_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags); 2792 } else if (strcmp(ivmode, "lmk") == 0) { 2793 cc->iv_gen_ops = &crypt_iv_lmk_ops; 2794 /* 2795 * Version 2 and 3 is recognised according 2796 * to length of provided multi-key string. 2797 * If present (version 3), last key is used as IV seed. 2798 * All keys (including IV seed) are always the same size. 2799 */ 2800 if (cc->key_size % cc->key_parts) { 2801 cc->key_parts++; 2802 cc->key_extra_size = cc->key_size / cc->key_parts; 2803 } 2804 } else if (strcmp(ivmode, "tcw") == 0) { 2805 cc->iv_gen_ops = &crypt_iv_tcw_ops; 2806 cc->key_parts += 2; /* IV + whitening */ 2807 cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE; 2808 } else if (strcmp(ivmode, "random") == 0) { 2809 cc->iv_gen_ops = &crypt_iv_random_ops; 2810 /* Need storage space in integrity fields. */ 2811 cc->integrity_iv_size = cc->iv_size; 2812 } else { 2813 ti->error = "Invalid IV mode"; 2814 return -EINVAL; 2815 } 2816 2817 return 0; 2818 } 2819 2820 /* 2821 * Workaround to parse HMAC algorithm from AEAD crypto API spec. 2822 * The HMAC is needed to calculate tag size (HMAC digest size). 2823 * This should be probably done by crypto-api calls (once available...) 2824 */ 2825 static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api) 2826 { 2827 char *start, *end, *mac_alg = NULL; 2828 struct crypto_ahash *mac; 2829 2830 if (!strstarts(cipher_api, "authenc(")) 2831 return 0; 2832 2833 start = strchr(cipher_api, '('); 2834 end = strchr(cipher_api, ','); 2835 if (!start || !end || ++start > end) 2836 return -EINVAL; 2837 2838 mac_alg = kmemdup_nul(start, end - start, GFP_KERNEL); 2839 if (!mac_alg) 2840 return -ENOMEM; 2841 2842 mac = crypto_alloc_ahash(mac_alg, 0, CRYPTO_ALG_ALLOCATES_MEMORY); 2843 kfree(mac_alg); 2844 2845 if (IS_ERR(mac)) 2846 return PTR_ERR(mac); 2847 2848 if (!test_bit(CRYPT_KEY_MAC_SIZE_SET, &cc->cipher_flags)) 2849 cc->key_mac_size = crypto_ahash_digestsize(mac); 2850 crypto_free_ahash(mac); 2851 2852 cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL); 2853 if (!cc->authenc_key) 2854 return -ENOMEM; 2855 2856 return 0; 2857 } 2858 2859 static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key, 2860 char **ivmode, char **ivopts) 2861 { 2862 struct crypt_config *cc = ti->private; 2863 char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME]; 2864 int ret = -EINVAL; 2865 2866 cc->tfms_count = 1; 2867 2868 /* 2869 * New format (capi: prefix) 2870 * capi:cipher_api_spec-iv:ivopts 2871 */ 2872 tmp = &cipher_in[strlen("capi:")]; 2873 2874 /* Separate IV options if present, it can contain another '-' in hash name */ 2875 *ivopts = strrchr(tmp, ':'); 2876 if (*ivopts) { 2877 **ivopts = '\0'; 2878 (*ivopts)++; 2879 } 2880 /* Parse IV mode */ 2881 *ivmode = strrchr(tmp, '-'); 2882 if (*ivmode) { 2883 **ivmode = '\0'; 2884 (*ivmode)++; 2885 } 2886 /* The rest is crypto API spec */ 2887 cipher_api = tmp; 2888 2889 /* Alloc AEAD, can be used only in new format. */ 2890 if (crypt_integrity_aead(cc)) { 2891 ret = crypt_ctr_auth_cipher(cc, cipher_api); 2892 if (ret < 0) { 2893 ti->error = "Invalid AEAD cipher spec"; 2894 return ret; 2895 } 2896 } 2897 2898 if (*ivmode && !strcmp(*ivmode, "lmk")) 2899 cc->tfms_count = 64; 2900 2901 if (*ivmode && !strcmp(*ivmode, "essiv")) { 2902 if (!*ivopts) { 2903 ti->error = "Digest algorithm missing for ESSIV mode"; 2904 return -EINVAL; 2905 } 2906 ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)", 2907 cipher_api, *ivopts); 2908 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 2909 ti->error = "Cannot allocate cipher string"; 2910 return -ENOMEM; 2911 } 2912 cipher_api = buf; 2913 } 2914 2915 cc->key_parts = cc->tfms_count; 2916 2917 /* Allocate cipher */ 2918 ret = crypt_alloc_tfms(cc, cipher_api); 2919 if (ret < 0) { 2920 ti->error = "Error allocating crypto tfm"; 2921 return ret; 2922 } 2923 2924 if (crypt_integrity_aead(cc)) 2925 cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc)); 2926 else 2927 cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc)); 2928 2929 return 0; 2930 } 2931 2932 static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key, 2933 char **ivmode, char **ivopts) 2934 { 2935 struct crypt_config *cc = ti->private; 2936 char *tmp, *cipher, *chainmode, *keycount; 2937 char *cipher_api = NULL; 2938 int ret = -EINVAL; 2939 char dummy; 2940 2941 if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) { 2942 ti->error = "Bad cipher specification"; 2943 return -EINVAL; 2944 } 2945 2946 /* 2947 * Legacy dm-crypt cipher specification 2948 * cipher[:keycount]-mode-iv:ivopts 2949 */ 2950 tmp = cipher_in; 2951 keycount = strsep(&tmp, "-"); 2952 cipher = strsep(&keycount, ":"); 2953 2954 if (!keycount) 2955 cc->tfms_count = 1; 2956 else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 || 2957 !is_power_of_2(cc->tfms_count)) { 2958 ti->error = "Bad cipher key count specification"; 2959 return -EINVAL; 2960 } 2961 cc->key_parts = cc->tfms_count; 2962 2963 chainmode = strsep(&tmp, "-"); 2964 *ivmode = strsep(&tmp, ":"); 2965 *ivopts = tmp; 2966 2967 /* 2968 * For compatibility with the original dm-crypt mapping format, if 2969 * only the cipher name is supplied, use cbc-plain. 2970 */ 2971 if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) { 2972 chainmode = "cbc"; 2973 *ivmode = "plain"; 2974 } 2975 2976 if (strcmp(chainmode, "ecb") && !*ivmode) { 2977 ti->error = "IV mechanism required"; 2978 return -EINVAL; 2979 } 2980 2981 cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL); 2982 if (!cipher_api) 2983 goto bad_mem; 2984 2985 if (*ivmode && !strcmp(*ivmode, "essiv")) { 2986 if (!*ivopts) { 2987 ti->error = "Digest algorithm missing for ESSIV mode"; 2988 kfree(cipher_api); 2989 return -EINVAL; 2990 } 2991 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 2992 "essiv(%s(%s),%s)", chainmode, cipher, *ivopts); 2993 } else { 2994 ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME, 2995 "%s(%s)", chainmode, cipher); 2996 } 2997 if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) { 2998 kfree(cipher_api); 2999 goto bad_mem; 3000 } 3001 3002 /* Allocate cipher */ 3003 ret = crypt_alloc_tfms(cc, cipher_api); 3004 if (ret < 0) { 3005 ti->error = "Error allocating crypto tfm"; 3006 kfree(cipher_api); 3007 return ret; 3008 } 3009 kfree(cipher_api); 3010 3011 return 0; 3012 bad_mem: 3013 ti->error = "Cannot allocate cipher strings"; 3014 return -ENOMEM; 3015 } 3016 3017 static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key) 3018 { 3019 struct crypt_config *cc = ti->private; 3020 char *ivmode = NULL, *ivopts = NULL; 3021 int ret; 3022 3023 cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL); 3024 if (!cc->cipher_string) { 3025 ti->error = "Cannot allocate cipher strings"; 3026 return -ENOMEM; 3027 } 3028 3029 if (strstarts(cipher_in, "capi:")) 3030 ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts); 3031 else 3032 ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts); 3033 if (ret) 3034 return ret; 3035 3036 /* Initialize IV */ 3037 ret = crypt_ctr_ivmode(ti, ivmode); 3038 if (ret < 0) 3039 return ret; 3040 3041 /* Initialize and set key */ 3042 ret = crypt_set_key(cc, key); 3043 if (ret < 0) { 3044 ti->error = "Error decoding and setting key"; 3045 return ret; 3046 } 3047 3048 /* Allocate IV */ 3049 if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) { 3050 ret = cc->iv_gen_ops->ctr(cc, ti, ivopts); 3051 if (ret < 0) { 3052 ti->error = "Error creating IV"; 3053 return ret; 3054 } 3055 } 3056 3057 /* Initialize IV (set keys for ESSIV etc) */ 3058 if (cc->iv_gen_ops && cc->iv_gen_ops->init) { 3059 ret = cc->iv_gen_ops->init(cc); 3060 if (ret < 0) { 3061 ti->error = "Error initialising IV"; 3062 return ret; 3063 } 3064 } 3065 3066 /* wipe the kernel key payload copy */ 3067 if (cc->key_string) 3068 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3069 3070 return ret; 3071 } 3072 3073 static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv) 3074 { 3075 struct crypt_config *cc = ti->private; 3076 struct dm_arg_set as; 3077 static const struct dm_arg _args[] = { 3078 {0, 9, "Invalid number of feature args"}, 3079 }; 3080 unsigned int opt_params, val; 3081 const char *opt_string, *sval; 3082 char dummy; 3083 int ret; 3084 3085 /* Optional parameters */ 3086 as.argc = argc; 3087 as.argv = argv; 3088 3089 ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error); 3090 if (ret) 3091 return ret; 3092 3093 while (opt_params--) { 3094 opt_string = dm_shift_arg(&as); 3095 if (!opt_string) { 3096 ti->error = "Not enough feature arguments"; 3097 return -EINVAL; 3098 } 3099 3100 if (!strcasecmp(opt_string, "allow_discards")) 3101 ti->num_discard_bios = 1; 3102 3103 else if (!strcasecmp(opt_string, "same_cpu_crypt")) 3104 set_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3105 else if (!strcasecmp(opt_string, "high_priority")) 3106 set_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags); 3107 3108 else if (!strcasecmp(opt_string, "submit_from_crypt_cpus")) 3109 set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3110 else if (!strcasecmp(opt_string, "no_read_workqueue")) 3111 set_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3112 else if (!strcasecmp(opt_string, "no_write_workqueue")) 3113 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3114 else if (sscanf(opt_string, "integrity:%u:", &val) == 1) { 3115 if (val == 0 || val > MAX_TAG_SIZE) { 3116 ti->error = "Invalid integrity arguments"; 3117 return -EINVAL; 3118 } 3119 cc->used_tag_size = val; 3120 sval = strchr(opt_string + strlen("integrity:"), ':') + 1; 3121 if (!strcasecmp(sval, "aead")) { 3122 set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags); 3123 } else if (strcasecmp(sval, "none")) { 3124 ti->error = "Unknown integrity profile"; 3125 return -EINVAL; 3126 } 3127 3128 cc->cipher_auth = kstrdup(sval, GFP_KERNEL); 3129 if (!cc->cipher_auth) 3130 return -ENOMEM; 3131 } else if (sscanf(opt_string, "integrity_key_size:%u%c", &val, &dummy) == 1) { 3132 if (!val) { 3133 ti->error = "Invalid integrity_key_size argument"; 3134 return -EINVAL; 3135 } 3136 cc->key_mac_size = val; 3137 set_bit(CRYPT_KEY_MAC_SIZE_SET, &cc->cipher_flags); 3138 } else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) { 3139 if (cc->sector_size < (1 << SECTOR_SHIFT) || 3140 cc->sector_size > 4096 || 3141 (cc->sector_size & (cc->sector_size - 1))) { 3142 ti->error = "Invalid feature value for sector_size"; 3143 return -EINVAL; 3144 } 3145 if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) { 3146 ti->error = "Device size is not multiple of sector_size feature"; 3147 return -EINVAL; 3148 } 3149 cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT; 3150 } else if (!strcasecmp(opt_string, "iv_large_sectors")) 3151 set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3152 else { 3153 ti->error = "Invalid feature arguments"; 3154 return -EINVAL; 3155 } 3156 } 3157 3158 return 0; 3159 } 3160 3161 #ifdef CONFIG_BLK_DEV_ZONED 3162 static int crypt_report_zones(struct dm_target *ti, 3163 struct dm_report_zones_args *args, unsigned int nr_zones) 3164 { 3165 struct crypt_config *cc = ti->private; 3166 3167 return dm_report_zones(cc->dev->bdev, cc->start, 3168 cc->start + dm_target_offset(ti, args->next_sector), 3169 args, nr_zones); 3170 } 3171 #else 3172 #define crypt_report_zones NULL 3173 #endif 3174 3175 /* 3176 * Construct an encryption mapping: 3177 * <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start> 3178 */ 3179 static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv) 3180 { 3181 struct crypt_config *cc; 3182 const char *devname = dm_table_device_name(ti->table); 3183 int key_size, wq_id; 3184 unsigned int align_mask; 3185 unsigned int common_wq_flags; 3186 unsigned long long tmpll; 3187 int ret; 3188 size_t iv_size_padding, additional_req_size; 3189 char dummy; 3190 3191 if (argc < 5) { 3192 ti->error = "Not enough arguments"; 3193 return -EINVAL; 3194 } 3195 3196 key_size = get_key_size(&argv[1]); 3197 if (key_size < 0) { 3198 ti->error = "Cannot parse key size"; 3199 return -EINVAL; 3200 } 3201 3202 cc = kzalloc_flex(*cc, key, key_size); 3203 if (!cc) { 3204 ti->error = "Cannot allocate encryption context"; 3205 return -ENOMEM; 3206 } 3207 cc->key_size = key_size; 3208 cc->sector_size = (1 << SECTOR_SHIFT); 3209 cc->sector_shift = 0; 3210 3211 ti->private = cc; 3212 3213 spin_lock(&dm_crypt_clients_lock); 3214 dm_crypt_clients_n++; 3215 crypt_calculate_pages_per_client(); 3216 spin_unlock(&dm_crypt_clients_lock); 3217 3218 ret = percpu_counter_init(&cc->n_allocated_pages, 0, GFP_KERNEL); 3219 if (ret < 0) 3220 goto bad; 3221 3222 /* Optional parameters need to be read before cipher constructor */ 3223 if (argc > 5) { 3224 ret = crypt_ctr_optional(ti, argc - 5, &argv[5]); 3225 if (ret) 3226 goto bad; 3227 } 3228 3229 ret = crypt_ctr_cipher(ti, argv[0], argv[1]); 3230 if (ret < 0) 3231 goto bad; 3232 3233 if (crypt_integrity_aead(cc)) { 3234 cc->dmreq_start = sizeof(struct aead_request); 3235 cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc)); 3236 align_mask = crypto_aead_alignmask(any_tfm_aead(cc)); 3237 } else { 3238 cc->dmreq_start = sizeof(struct skcipher_request); 3239 cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc)); 3240 align_mask = crypto_skcipher_alignmask(any_tfm(cc)); 3241 } 3242 cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request)); 3243 3244 if (align_mask < CRYPTO_MINALIGN) { 3245 /* Allocate the padding exactly */ 3246 iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request)) 3247 & align_mask; 3248 } else { 3249 /* 3250 * If the cipher requires greater alignment than kmalloc 3251 * alignment, we don't know the exact position of the 3252 * initialization vector. We must assume worst case. 3253 */ 3254 iv_size_padding = align_mask; 3255 } 3256 3257 /* ...| IV + padding | original IV | original sec. number | bio tag offset | */ 3258 additional_req_size = sizeof(struct dm_crypt_request) + 3259 iv_size_padding + cc->iv_size + 3260 cc->iv_size + 3261 sizeof(uint64_t) + 3262 sizeof(unsigned int); 3263 3264 ret = mempool_init_kmalloc_pool(&cc->req_pool, MIN_IOS, cc->dmreq_start + additional_req_size); 3265 if (ret) { 3266 ti->error = "Cannot allocate crypt request mempool"; 3267 goto bad; 3268 } 3269 3270 cc->per_bio_data_size = ti->per_io_data_size = 3271 ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size, 3272 ARCH_DMA_MINALIGN); 3273 3274 ret = mempool_init(&cc->page_pool, BIO_MAX_VECS, crypt_page_alloc, crypt_page_free, cc); 3275 if (ret) { 3276 ti->error = "Cannot allocate page mempool"; 3277 goto bad; 3278 } 3279 3280 ret = bioset_init(&cc->bs, MIN_IOS, 0, BIOSET_NEED_BVECS); 3281 if (ret) { 3282 ti->error = "Cannot allocate crypt bioset"; 3283 goto bad; 3284 } 3285 3286 mutex_init(&cc->bio_alloc_lock); 3287 3288 ret = -EINVAL; 3289 if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) || 3290 (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) { 3291 ti->error = "Invalid iv_offset sector"; 3292 goto bad; 3293 } 3294 cc->iv_offset = tmpll; 3295 3296 ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev); 3297 if (ret) { 3298 ti->error = "Device lookup failed"; 3299 goto bad; 3300 } 3301 3302 ret = -EINVAL; 3303 if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) { 3304 ti->error = "Invalid device sector"; 3305 goto bad; 3306 } 3307 cc->start = tmpll; 3308 3309 if (bdev_is_zoned(cc->dev->bdev)) { 3310 /* 3311 * For zoned block devices, we need to preserve the issuer write 3312 * ordering. To do so, disable write workqueues and force inline 3313 * encryption completion. 3314 */ 3315 set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3316 set_bit(DM_CRYPT_WRITE_INLINE, &cc->flags); 3317 3318 /* 3319 * All zone append writes to a zone of a zoned block device will 3320 * have the same BIO sector, the start of the zone. When the 3321 * cypher IV mode uses sector values, all data targeting a 3322 * zone will be encrypted using the first sector numbers of the 3323 * zone. This will not result in write errors but will 3324 * cause most reads to fail as reads will use the sector values 3325 * for the actual data locations, resulting in IV mismatch. 3326 * To avoid this problem, ask DM core to emulate zone append 3327 * operations with regular writes. 3328 */ 3329 DMDEBUG("Zone append operations will be emulated"); 3330 ti->emulate_zone_append = true; 3331 } 3332 3333 if (crypt_integrity_aead(cc) || cc->integrity_iv_size) { 3334 ret = crypt_integrity_ctr(cc, ti); 3335 if (ret) 3336 goto bad; 3337 3338 cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->tuple_size; 3339 if (!cc->tag_pool_max_sectors) 3340 cc->tag_pool_max_sectors = 1; 3341 3342 ret = mempool_init_kmalloc_pool(&cc->tag_pool, MIN_IOS, 3343 cc->tag_pool_max_sectors * cc->tuple_size); 3344 if (ret) { 3345 ti->error = "Cannot allocate integrity tags mempool"; 3346 goto bad; 3347 } 3348 3349 cc->tag_pool_max_sectors <<= cc->sector_shift; 3350 } 3351 3352 wq_id = ida_alloc_min(&workqueue_ida, 1, GFP_KERNEL); 3353 if (wq_id < 0) { 3354 ti->error = "Couldn't get workqueue id"; 3355 ret = wq_id; 3356 goto bad; 3357 } 3358 cc->workqueue_id = wq_id; 3359 3360 ret = -ENOMEM; 3361 common_wq_flags = WQ_MEM_RECLAIM | WQ_SYSFS; 3362 if (test_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags)) 3363 common_wq_flags |= WQ_HIGHPRI; 3364 3365 cc->io_queue = alloc_workqueue("kcryptd_io-%s-%d", 3366 common_wq_flags | WQ_PERCPU, 1, 3367 devname, wq_id); 3368 if (!cc->io_queue) { 3369 ti->error = "Couldn't create kcryptd io queue"; 3370 goto bad; 3371 } 3372 3373 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) { 3374 cc->crypt_queue = alloc_workqueue("kcryptd-%s-%d", 3375 common_wq_flags | WQ_CPU_INTENSIVE | WQ_PERCPU, 3376 1, devname, wq_id); 3377 } else { 3378 /* 3379 * While crypt_queue is certainly CPU intensive, the use of 3380 * WQ_CPU_INTENSIVE is meaningless with WQ_UNBOUND. 3381 */ 3382 cc->crypt_queue = alloc_workqueue("kcryptd-%s-%d", 3383 common_wq_flags | WQ_UNBOUND, 3384 num_online_cpus(), devname, wq_id); 3385 } 3386 if (!cc->crypt_queue) { 3387 ti->error = "Couldn't create kcryptd queue"; 3388 goto bad; 3389 } 3390 3391 spin_lock_init(&cc->write_thread_lock); 3392 cc->write_tree = RB_ROOT; 3393 3394 cc->write_thread = kthread_run(dmcrypt_write, cc, "dmcrypt_write/%s", devname); 3395 if (IS_ERR(cc->write_thread)) { 3396 ret = PTR_ERR(cc->write_thread); 3397 cc->write_thread = NULL; 3398 ti->error = "Couldn't spawn write thread"; 3399 goto bad; 3400 } 3401 if (test_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags)) 3402 set_user_nice(cc->write_thread, MIN_NICE); 3403 3404 ti->num_flush_bios = 1; 3405 ti->limit_swap_bios = true; 3406 ti->accounts_remapped_io = true; 3407 3408 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 1); 3409 return 0; 3410 3411 bad: 3412 dm_audit_log_ctr(DM_MSG_PREFIX, ti, 0); 3413 crypt_dtr(ti); 3414 return ret; 3415 } 3416 3417 static int crypt_map(struct dm_target *ti, struct bio *bio) 3418 { 3419 struct dm_crypt_io *io; 3420 struct crypt_config *cc = ti->private; 3421 unsigned max_sectors; 3422 bool no_split; 3423 3424 /* 3425 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues. 3426 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight 3427 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters 3428 */ 3429 if (unlikely(bio->bi_opf & REQ_PREFLUSH || 3430 bio_op(bio) == REQ_OP_DISCARD)) { 3431 bio_set_dev(bio, cc->dev->bdev); 3432 if (bio_sectors(bio)) 3433 bio->bi_iter.bi_sector = cc->start + 3434 dm_target_offset(ti, bio->bi_iter.bi_sector); 3435 return DM_MAPIO_REMAPPED; 3436 } 3437 3438 /* 3439 * Check if bio is too large, split as needed. 3440 * 3441 * For zoned devices, splitting write operations creates the 3442 * risk of deadlocking queue freeze operations with zone write 3443 * plugging BIO work when the reminder of a split BIO is 3444 * issued. So always allow the entire BIO to proceed. 3445 */ 3446 no_split = (ti->emulate_zone_append && op_is_write(bio_op(bio))) || 3447 (bio->bi_opf & REQ_ATOMIC); 3448 max_sectors = get_max_request_sectors(ti, bio, no_split); 3449 if (unlikely(bio_sectors(bio) > max_sectors)) { 3450 if (unlikely(no_split)) 3451 return DM_MAPIO_KILL; 3452 dm_accept_partial_bio(bio, max_sectors); 3453 } 3454 3455 /* 3456 * Ensure that bio is a multiple of internal sector encryption size 3457 * and is aligned to this size as defined in IO hints. 3458 */ 3459 if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0)) 3460 return DM_MAPIO_KILL; 3461 3462 if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1))) 3463 return DM_MAPIO_KILL; 3464 3465 io = dm_per_bio_data(bio, cc->per_bio_data_size); 3466 crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector)); 3467 3468 if (cc->tuple_size) { 3469 unsigned int tag_len = cc->tuple_size * (bio_sectors(bio) >> cc->sector_shift); 3470 3471 if (unlikely(tag_len > KMALLOC_MAX_SIZE)) 3472 io->integrity_metadata = NULL; 3473 else 3474 io->integrity_metadata = kmalloc(tag_len, GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN); 3475 3476 if (unlikely(!io->integrity_metadata)) { 3477 if (bio_sectors(bio) > cc->tag_pool_max_sectors) 3478 dm_accept_partial_bio(bio, cc->tag_pool_max_sectors); 3479 io->integrity_metadata = mempool_alloc(&cc->tag_pool, GFP_NOIO); 3480 io->integrity_metadata_from_pool = true; 3481 } 3482 } 3483 3484 if (crypt_integrity_aead(cc)) 3485 io->ctx.r.req_aead = (struct aead_request *)(io + 1); 3486 else 3487 io->ctx.r.req = (struct skcipher_request *)(io + 1); 3488 3489 if (bio_data_dir(io->base_bio) == READ) { 3490 if (kcryptd_io_read(io, CRYPT_MAP_READ_GFP)) 3491 kcryptd_queue_read(io); 3492 } else 3493 kcryptd_queue_crypt(io); 3494 3495 return DM_MAPIO_SUBMITTED; 3496 } 3497 3498 static char hex2asc(unsigned char c) 3499 { 3500 return c + '0' + ((unsigned int)(9 - c) >> 4 & 0x27); 3501 } 3502 3503 static void crypt_status(struct dm_target *ti, status_type_t type, 3504 unsigned int status_flags, char *result, unsigned int maxlen) 3505 { 3506 struct crypt_config *cc = ti->private; 3507 unsigned int i, sz = 0; 3508 int num_feature_args = 0; 3509 3510 switch (type) { 3511 case STATUSTYPE_INFO: 3512 result[0] = '\0'; 3513 break; 3514 3515 case STATUSTYPE_TABLE: 3516 DMEMIT("%s ", cc->cipher_string); 3517 3518 if (cc->key_size > 0) { 3519 if (cc->key_string) 3520 DMEMIT(":%u:%s", cc->key_size, cc->key_string); 3521 else { 3522 for (i = 0; i < cc->key_size; i++) { 3523 DMEMIT("%c%c", hex2asc(cc->key[i] >> 4), 3524 hex2asc(cc->key[i] & 0xf)); 3525 } 3526 } 3527 } else 3528 DMEMIT("-"); 3529 3530 DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset, 3531 cc->dev->name, (unsigned long long)cc->start); 3532 3533 num_feature_args += !!ti->num_discard_bios; 3534 num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags); 3535 num_feature_args += test_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags); 3536 num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags); 3537 num_feature_args += test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags); 3538 num_feature_args += test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags); 3539 num_feature_args += !!cc->used_tag_size; 3540 num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT); 3541 num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags); 3542 num_feature_args += test_bit(CRYPT_KEY_MAC_SIZE_SET, &cc->cipher_flags); 3543 if (num_feature_args) { 3544 DMEMIT(" %d", num_feature_args); 3545 if (ti->num_discard_bios) 3546 DMEMIT(" allow_discards"); 3547 if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags)) 3548 DMEMIT(" same_cpu_crypt"); 3549 if (test_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags)) 3550 DMEMIT(" high_priority"); 3551 if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) 3552 DMEMIT(" submit_from_crypt_cpus"); 3553 if (test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) 3554 DMEMIT(" no_read_workqueue"); 3555 if (test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) 3556 DMEMIT(" no_write_workqueue"); 3557 if (cc->used_tag_size) 3558 DMEMIT(" integrity:%u:%s", cc->used_tag_size, cc->cipher_auth); 3559 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3560 DMEMIT(" sector_size:%d", cc->sector_size); 3561 if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags)) 3562 DMEMIT(" iv_large_sectors"); 3563 if (test_bit(CRYPT_KEY_MAC_SIZE_SET, &cc->cipher_flags)) 3564 DMEMIT(" integrity_key_size:%u", cc->key_mac_size); 3565 } 3566 break; 3567 3568 case STATUSTYPE_IMA: 3569 DMEMIT_TARGET_NAME_VERSION(ti->type); 3570 DMEMIT(",allow_discards=%c", ti->num_discard_bios ? 'y' : 'n'); 3571 DMEMIT(",same_cpu_crypt=%c", test_bit(DM_CRYPT_SAME_CPU, &cc->flags) ? 'y' : 'n'); 3572 DMEMIT(",high_priority=%c", test_bit(DM_CRYPT_HIGH_PRIORITY, &cc->flags) ? 'y' : 'n'); 3573 DMEMIT(",submit_from_crypt_cpus=%c", test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags) ? 3574 'y' : 'n'); 3575 DMEMIT(",no_read_workqueue=%c", test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags) ? 3576 'y' : 'n'); 3577 DMEMIT(",no_write_workqueue=%c", test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags) ? 3578 'y' : 'n'); 3579 DMEMIT(",iv_large_sectors=%c", test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags) ? 3580 'y' : 'n'); 3581 3582 if (cc->used_tag_size) 3583 DMEMIT(",integrity_tag_size=%u,cipher_auth=%s", 3584 cc->used_tag_size, cc->cipher_auth); 3585 if (cc->sector_size != (1 << SECTOR_SHIFT)) 3586 DMEMIT(",sector_size=%d", cc->sector_size); 3587 if (cc->cipher_string) 3588 DMEMIT(",cipher_string=%s", cc->cipher_string); 3589 3590 DMEMIT(",key_size=%u", cc->key_size); 3591 DMEMIT(",key_parts=%u", cc->key_parts); 3592 DMEMIT(",key_extra_size=%u", cc->key_extra_size); 3593 DMEMIT(",key_mac_size=%u", cc->key_mac_size); 3594 DMEMIT(";"); 3595 break; 3596 } 3597 } 3598 3599 static void crypt_postsuspend(struct dm_target *ti) 3600 { 3601 struct crypt_config *cc = ti->private; 3602 3603 set_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3604 } 3605 3606 static int crypt_preresume(struct dm_target *ti) 3607 { 3608 struct crypt_config *cc = ti->private; 3609 3610 if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) { 3611 DMERR("aborting resume - crypt key is not set."); 3612 return -EAGAIN; 3613 } 3614 3615 return 0; 3616 } 3617 3618 static void crypt_resume(struct dm_target *ti) 3619 { 3620 struct crypt_config *cc = ti->private; 3621 3622 clear_bit(DM_CRYPT_SUSPENDED, &cc->flags); 3623 } 3624 3625 /* Message interface 3626 * key set <key> 3627 * key wipe 3628 */ 3629 static int crypt_message(struct dm_target *ti, unsigned int argc, char **argv, 3630 char *result, unsigned int maxlen) 3631 { 3632 struct crypt_config *cc = ti->private; 3633 int key_size, ret = -EINVAL; 3634 3635 if (argc < 2) 3636 goto error; 3637 3638 if (!strcasecmp(argv[0], "key")) { 3639 if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) { 3640 DMWARN("not suspended during key manipulation."); 3641 return -EINVAL; 3642 } 3643 if (argc == 3 && !strcasecmp(argv[1], "set")) { 3644 /* The key size may not be changed. */ 3645 key_size = get_key_size(&argv[2]); 3646 if (key_size < 0 || cc->key_size != key_size) { 3647 memset(argv[2], '0', strlen(argv[2])); 3648 return -EINVAL; 3649 } 3650 3651 ret = crypt_set_key(cc, argv[2]); 3652 if (ret) 3653 return ret; 3654 if (cc->iv_gen_ops && cc->iv_gen_ops->init) 3655 ret = cc->iv_gen_ops->init(cc); 3656 /* wipe the kernel key payload copy */ 3657 if (cc->key_string) 3658 memset(cc->key, 0, cc->key_size * sizeof(u8)); 3659 return ret; 3660 } 3661 if (argc == 2 && !strcasecmp(argv[1], "wipe")) 3662 return crypt_wipe_key(cc); 3663 } 3664 3665 error: 3666 DMWARN("unrecognised message received."); 3667 return -EINVAL; 3668 } 3669 3670 static int crypt_iterate_devices(struct dm_target *ti, 3671 iterate_devices_callout_fn fn, void *data) 3672 { 3673 struct crypt_config *cc = ti->private; 3674 3675 return fn(ti, cc->dev, cc->start, ti->len, data); 3676 } 3677 3678 static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits) 3679 { 3680 struct crypt_config *cc = ti->private; 3681 3682 dm_stack_bs_limits(limits, cc->sector_size); 3683 limits->dma_alignment = limits->logical_block_size - 1; 3684 3685 /* 3686 * For zoned dm-crypt targets, there will be no internal splitting of 3687 * write BIOs to avoid exceeding BIO_MAX_VECS vectors per BIO. But 3688 * without respecting this limit, crypt_alloc_buffer() will trigger a 3689 * BUG(). Avoid this by forcing DM core to split write BIOs to this 3690 * limit. 3691 */ 3692 if (ti->emulate_zone_append) 3693 limits->max_hw_sectors = min(limits->max_hw_sectors, 3694 BIO_MAX_VECS << PAGE_SECTORS_SHIFT); 3695 3696 limits->atomic_write_hw_unit_max = min(limits->atomic_write_hw_unit_max, 3697 BIO_MAX_VECS << PAGE_SHIFT); 3698 limits->atomic_write_hw_max = min(limits->atomic_write_hw_max, 3699 BIO_MAX_VECS << PAGE_SHIFT); 3700 } 3701 3702 static struct target_type crypt_target = { 3703 .name = "crypt", 3704 .version = {1, 29, 0}, 3705 .module = THIS_MODULE, 3706 .ctr = crypt_ctr, 3707 .dtr = crypt_dtr, 3708 .features = DM_TARGET_ZONED_HM | DM_TARGET_ATOMIC_WRITES, 3709 .report_zones = crypt_report_zones, 3710 .map = crypt_map, 3711 .status = crypt_status, 3712 .postsuspend = crypt_postsuspend, 3713 .preresume = crypt_preresume, 3714 .resume = crypt_resume, 3715 .message = crypt_message, 3716 .iterate_devices = crypt_iterate_devices, 3717 .io_hints = crypt_io_hints, 3718 }; 3719 module_dm(crypt); 3720 3721 MODULE_AUTHOR("Jana Saout <jana@saout.de>"); 3722 MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption"); 3723 MODULE_LICENSE("GPL"); 3724