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v5.9
 
   1/*
   2 * Copyright (C) 2003 Jana Saout <jana@saout.de>
   3 * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org>
   4 * Copyright (C) 2006-2020 Red Hat, Inc. All rights reserved.
   5 * Copyright (C) 2013-2020 Milan Broz <gmazyland@gmail.com>
   6 *
   7 * This file is released under the GPL.
   8 */
   9
  10#include <linux/completion.h>
  11#include <linux/err.h>
  12#include <linux/module.h>
  13#include <linux/init.h>
  14#include <linux/kernel.h>
  15#include <linux/key.h>
  16#include <linux/bio.h>
  17#include <linux/blkdev.h>
 
  18#include <linux/mempool.h>
  19#include <linux/slab.h>
  20#include <linux/crypto.h>
  21#include <linux/workqueue.h>
  22#include <linux/kthread.h>
  23#include <linux/backing-dev.h>
  24#include <linux/atomic.h>
  25#include <linux/scatterlist.h>
  26#include <linux/rbtree.h>
  27#include <linux/ctype.h>
  28#include <asm/page.h>
  29#include <asm/unaligned.h>
  30#include <crypto/hash.h>
  31#include <crypto/md5.h>
  32#include <crypto/algapi.h>
  33#include <crypto/skcipher.h>
  34#include <crypto/aead.h>
  35#include <crypto/authenc.h>
 
  36#include <linux/rtnetlink.h> /* for struct rtattr and RTA macros only */
  37#include <linux/key-type.h>
  38#include <keys/user-type.h>
  39#include <keys/encrypted-type.h>
 
  40
  41#include <linux/device-mapper.h>
  42
 
 
  43#define DM_MSG_PREFIX "crypt"
  44
  45/*
  46 * context holding the current state of a multi-part conversion
  47 */
  48struct convert_context {
  49	struct completion restart;
  50	struct bio *bio_in;
  51	struct bio *bio_out;
  52	struct bvec_iter iter_in;
 
  53	struct bvec_iter iter_out;
  54	u64 cc_sector;
  55	atomic_t cc_pending;
 
  56	union {
  57		struct skcipher_request *req;
  58		struct aead_request *req_aead;
  59	} r;
 
 
  60
  61};
  62
  63/*
  64 * per bio private data
  65 */
  66struct dm_crypt_io {
  67	struct crypt_config *cc;
  68	struct bio *base_bio;
  69	u8 *integrity_metadata;
  70	bool integrity_metadata_from_pool;
 
  71	struct work_struct work;
  72	struct tasklet_struct tasklet;
  73
  74	struct convert_context ctx;
  75
  76	atomic_t io_pending;
  77	blk_status_t error;
  78	sector_t sector;
  79
 
 
  80	struct rb_node rb_node;
  81} CRYPTO_MINALIGN_ATTR;
  82
  83struct dm_crypt_request {
  84	struct convert_context *ctx;
  85	struct scatterlist sg_in[4];
  86	struct scatterlist sg_out[4];
  87	u64 iv_sector;
  88};
  89
  90struct crypt_config;
  91
  92struct crypt_iv_operations {
  93	int (*ctr)(struct crypt_config *cc, struct dm_target *ti,
  94		   const char *opts);
  95	void (*dtr)(struct crypt_config *cc);
  96	int (*init)(struct crypt_config *cc);
  97	int (*wipe)(struct crypt_config *cc);
  98	int (*generator)(struct crypt_config *cc, u8 *iv,
  99			 struct dm_crypt_request *dmreq);
 100	int (*post)(struct crypt_config *cc, u8 *iv,
 101		    struct dm_crypt_request *dmreq);
 102};
 103
 104struct iv_benbi_private {
 105	int shift;
 106};
 107
 108#define LMK_SEED_SIZE 64 /* hash + 0 */
 109struct iv_lmk_private {
 110	struct crypto_shash *hash_tfm;
 111	u8 *seed;
 112};
 113
 114#define TCW_WHITENING_SIZE 16
 115struct iv_tcw_private {
 116	struct crypto_shash *crc32_tfm;
 117	u8 *iv_seed;
 118	u8 *whitening;
 119};
 120
 121#define ELEPHANT_MAX_KEY_SIZE 32
 122struct iv_elephant_private {
 123	struct crypto_skcipher *tfm;
 124};
 125
 126/*
 127 * Crypt: maps a linear range of a block device
 128 * and encrypts / decrypts at the same time.
 129 */
 130enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID,
 131	     DM_CRYPT_SAME_CPU, DM_CRYPT_NO_OFFLOAD,
 132	     DM_CRYPT_NO_READ_WORKQUEUE, DM_CRYPT_NO_WRITE_WORKQUEUE,
 133	     DM_CRYPT_WRITE_INLINE };
 134
 135enum cipher_flags {
 136	CRYPT_MODE_INTEGRITY_AEAD,	/* Use authenticated mode for cihper */
 137	CRYPT_IV_LARGE_SECTORS,		/* Calculate IV from sector_size, not 512B sectors */
 138	CRYPT_ENCRYPT_PREPROCESS,	/* Must preprocess data for encryption (elephant) */
 139};
 140
 141/*
 142 * The fields in here must be read only after initialization.
 143 */
 144struct crypt_config {
 145	struct dm_dev *dev;
 146	sector_t start;
 147
 148	struct percpu_counter n_allocated_pages;
 149
 150	struct workqueue_struct *io_queue;
 151	struct workqueue_struct *crypt_queue;
 152
 153	spinlock_t write_thread_lock;
 154	struct task_struct *write_thread;
 155	struct rb_root write_tree;
 156
 157	char *cipher_string;
 158	char *cipher_auth;
 159	char *key_string;
 160
 161	const struct crypt_iv_operations *iv_gen_ops;
 162	union {
 163		struct iv_benbi_private benbi;
 164		struct iv_lmk_private lmk;
 165		struct iv_tcw_private tcw;
 166		struct iv_elephant_private elephant;
 167	} iv_gen_private;
 168	u64 iv_offset;
 169	unsigned int iv_size;
 170	unsigned short int sector_size;
 171	unsigned char sector_shift;
 172
 173	union {
 174		struct crypto_skcipher **tfms;
 175		struct crypto_aead **tfms_aead;
 176	} cipher_tfm;
 177	unsigned tfms_count;
 178	unsigned long cipher_flags;
 179
 180	/*
 181	 * Layout of each crypto request:
 182	 *
 183	 *   struct skcipher_request
 184	 *      context
 185	 *      padding
 186	 *   struct dm_crypt_request
 187	 *      padding
 188	 *   IV
 189	 *
 190	 * The padding is added so that dm_crypt_request and the IV are
 191	 * correctly aligned.
 192	 */
 193	unsigned int dmreq_start;
 194
 195	unsigned int per_bio_data_size;
 196
 197	unsigned long flags;
 198	unsigned int key_size;
 199	unsigned int key_parts;      /* independent parts in key buffer */
 200	unsigned int key_extra_size; /* additional keys length */
 201	unsigned int key_mac_size;   /* MAC key size for authenc(...) */
 202
 203	unsigned int integrity_tag_size;
 204	unsigned int integrity_iv_size;
 205	unsigned int on_disk_tag_size;
 206
 207	/*
 208	 * pool for per bio private data, crypto requests,
 209	 * encryption requeusts/buffer pages and integrity tags
 210	 */
 211	unsigned tag_pool_max_sectors;
 212	mempool_t tag_pool;
 213	mempool_t req_pool;
 214	mempool_t page_pool;
 215
 216	struct bio_set bs;
 217	struct mutex bio_alloc_lock;
 218
 219	u8 *authenc_key; /* space for keys in authenc() format (if used) */
 220	u8 key[];
 221};
 222
 223#define MIN_IOS		64
 224#define MAX_TAG_SIZE	480
 225#define POOL_ENTRY_SIZE	512
 226
 227static DEFINE_SPINLOCK(dm_crypt_clients_lock);
 228static unsigned dm_crypt_clients_n = 0;
 229static volatile unsigned long dm_crypt_pages_per_client;
 230#define DM_CRYPT_MEMORY_PERCENT			2
 231#define DM_CRYPT_MIN_PAGES_PER_CLIENT		(BIO_MAX_PAGES * 16)
 232
 233static void clone_init(struct dm_crypt_io *, struct bio *);
 234static void kcryptd_queue_crypt(struct dm_crypt_io *io);
 235static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc,
 236					     struct scatterlist *sg);
 237
 238static bool crypt_integrity_aead(struct crypt_config *cc);
 239
 240/*
 241 * Use this to access cipher attributes that are independent of the key.
 242 */
 243static struct crypto_skcipher *any_tfm(struct crypt_config *cc)
 244{
 245	return cc->cipher_tfm.tfms[0];
 246}
 247
 248static struct crypto_aead *any_tfm_aead(struct crypt_config *cc)
 249{
 250	return cc->cipher_tfm.tfms_aead[0];
 251}
 252
 253/*
 254 * Different IV generation algorithms:
 255 *
 256 * plain: the initial vector is the 32-bit little-endian version of the sector
 257 *        number, padded with zeros if necessary.
 258 *
 259 * plain64: the initial vector is the 64-bit little-endian version of the sector
 260 *        number, padded with zeros if necessary.
 261 *
 262 * plain64be: the initial vector is the 64-bit big-endian version of the sector
 263 *        number, padded with zeros if necessary.
 264 *
 265 * essiv: "encrypted sector|salt initial vector", the sector number is
 266 *        encrypted with the bulk cipher using a salt as key. The salt
 267 *        should be derived from the bulk cipher's key via hashing.
 268 *
 269 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1
 270 *        (needed for LRW-32-AES and possible other narrow block modes)
 271 *
 272 * null: the initial vector is always zero.  Provides compatibility with
 273 *       obsolete loop_fish2 devices.  Do not use for new devices.
 274 *
 275 * lmk:  Compatible implementation of the block chaining mode used
 276 *       by the Loop-AES block device encryption system
 277 *       designed by Jari Ruusu. See http://loop-aes.sourceforge.net/
 278 *       It operates on full 512 byte sectors and uses CBC
 279 *       with an IV derived from the sector number, the data and
 280 *       optionally extra IV seed.
 281 *       This means that after decryption the first block
 282 *       of sector must be tweaked according to decrypted data.
 283 *       Loop-AES can use three encryption schemes:
 284 *         version 1: is plain aes-cbc mode
 285 *         version 2: uses 64 multikey scheme with lmk IV generator
 286 *         version 3: the same as version 2 with additional IV seed
 287 *                   (it uses 65 keys, last key is used as IV seed)
 288 *
 289 * tcw:  Compatible implementation of the block chaining mode used
 290 *       by the TrueCrypt device encryption system (prior to version 4.1).
 291 *       For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat
 292 *       It operates on full 512 byte sectors and uses CBC
 293 *       with an IV derived from initial key and the sector number.
 294 *       In addition, whitening value is applied on every sector, whitening
 295 *       is calculated from initial key, sector number and mixed using CRC32.
 296 *       Note that this encryption scheme is vulnerable to watermarking attacks
 297 *       and should be used for old compatible containers access only.
 298 *
 299 * eboiv: Encrypted byte-offset IV (used in Bitlocker in CBC mode)
 300 *        The IV is encrypted little-endian byte-offset (with the same key
 301 *        and cipher as the volume).
 302 *
 303 * elephant: The extended version of eboiv with additional Elephant diffuser
 304 *           used with Bitlocker CBC mode.
 305 *           This mode was used in older Windows systems
 306 *           https://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf
 307 */
 308
 309static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv,
 310			      struct dm_crypt_request *dmreq)
 311{
 312	memset(iv, 0, cc->iv_size);
 313	*(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff);
 314
 315	return 0;
 316}
 317
 318static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv,
 319				struct dm_crypt_request *dmreq)
 320{
 321	memset(iv, 0, cc->iv_size);
 322	*(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
 323
 324	return 0;
 325}
 326
 327static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv,
 328				  struct dm_crypt_request *dmreq)
 329{
 330	memset(iv, 0, cc->iv_size);
 331	/* iv_size is at least of size u64; usually it is 16 bytes */
 332	*(__be64 *)&iv[cc->iv_size - sizeof(u64)] = cpu_to_be64(dmreq->iv_sector);
 333
 334	return 0;
 335}
 336
 337static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv,
 338			      struct dm_crypt_request *dmreq)
 339{
 340	/*
 341	 * ESSIV encryption of the IV is now handled by the crypto API,
 342	 * so just pass the plain sector number here.
 343	 */
 344	memset(iv, 0, cc->iv_size);
 345	*(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
 346
 347	return 0;
 348}
 349
 350static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti,
 351			      const char *opts)
 352{
 353	unsigned bs;
 354	int log;
 355
 356	if (crypt_integrity_aead(cc))
 357		bs = crypto_aead_blocksize(any_tfm_aead(cc));
 358	else
 359		bs = crypto_skcipher_blocksize(any_tfm(cc));
 360	log = ilog2(bs);
 361
 362	/* we need to calculate how far we must shift the sector count
 363	 * to get the cipher block count, we use this shift in _gen */
 364
 
 365	if (1 << log != bs) {
 366		ti->error = "cypher blocksize is not a power of 2";
 367		return -EINVAL;
 368	}
 369
 370	if (log > 9) {
 371		ti->error = "cypher blocksize is > 512";
 372		return -EINVAL;
 373	}
 374
 375	cc->iv_gen_private.benbi.shift = 9 - log;
 376
 377	return 0;
 378}
 379
 380static void crypt_iv_benbi_dtr(struct crypt_config *cc)
 381{
 382}
 383
 384static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv,
 385			      struct dm_crypt_request *dmreq)
 386{
 387	__be64 val;
 388
 389	memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */
 390
 391	val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1);
 392	put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64)));
 393
 394	return 0;
 395}
 396
 397static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv,
 398			     struct dm_crypt_request *dmreq)
 399{
 400	memset(iv, 0, cc->iv_size);
 401
 402	return 0;
 403}
 404
 405static void crypt_iv_lmk_dtr(struct crypt_config *cc)
 406{
 407	struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
 408
 409	if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm))
 410		crypto_free_shash(lmk->hash_tfm);
 411	lmk->hash_tfm = NULL;
 412
 413	kfree_sensitive(lmk->seed);
 414	lmk->seed = NULL;
 415}
 416
 417static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti,
 418			    const char *opts)
 419{
 420	struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
 421
 422	if (cc->sector_size != (1 << SECTOR_SHIFT)) {
 423		ti->error = "Unsupported sector size for LMK";
 424		return -EINVAL;
 425	}
 426
 427	lmk->hash_tfm = crypto_alloc_shash("md5", 0, 0);
 
 428	if (IS_ERR(lmk->hash_tfm)) {
 429		ti->error = "Error initializing LMK hash";
 430		return PTR_ERR(lmk->hash_tfm);
 431	}
 432
 433	/* No seed in LMK version 2 */
 434	if (cc->key_parts == cc->tfms_count) {
 435		lmk->seed = NULL;
 436		return 0;
 437	}
 438
 439	lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL);
 440	if (!lmk->seed) {
 441		crypt_iv_lmk_dtr(cc);
 442		ti->error = "Error kmallocing seed storage in LMK";
 443		return -ENOMEM;
 444	}
 445
 446	return 0;
 447}
 448
 449static int crypt_iv_lmk_init(struct crypt_config *cc)
 450{
 451	struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
 452	int subkey_size = cc->key_size / cc->key_parts;
 453
 454	/* LMK seed is on the position of LMK_KEYS + 1 key */
 455	if (lmk->seed)
 456		memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size),
 457		       crypto_shash_digestsize(lmk->hash_tfm));
 458
 459	return 0;
 460}
 461
 462static int crypt_iv_lmk_wipe(struct crypt_config *cc)
 463{
 464	struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
 465
 466	if (lmk->seed)
 467		memset(lmk->seed, 0, LMK_SEED_SIZE);
 468
 469	return 0;
 470}
 471
 472static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
 473			    struct dm_crypt_request *dmreq,
 474			    u8 *data)
 475{
 476	struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
 477	SHASH_DESC_ON_STACK(desc, lmk->hash_tfm);
 478	struct md5_state md5state;
 479	__le32 buf[4];
 480	int i, r;
 481
 482	desc->tfm = lmk->hash_tfm;
 483
 484	r = crypto_shash_init(desc);
 485	if (r)
 486		return r;
 487
 488	if (lmk->seed) {
 489		r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE);
 490		if (r)
 491			return r;
 492	}
 493
 494	/* Sector is always 512B, block size 16, add data of blocks 1-31 */
 495	r = crypto_shash_update(desc, data + 16, 16 * 31);
 496	if (r)
 497		return r;
 498
 499	/* Sector is cropped to 56 bits here */
 500	buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF);
 501	buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000);
 502	buf[2] = cpu_to_le32(4024);
 503	buf[3] = 0;
 504	r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf));
 505	if (r)
 506		return r;
 507
 508	/* No MD5 padding here */
 509	r = crypto_shash_export(desc, &md5state);
 510	if (r)
 511		return r;
 512
 513	for (i = 0; i < MD5_HASH_WORDS; i++)
 514		__cpu_to_le32s(&md5state.hash[i]);
 515	memcpy(iv, &md5state.hash, cc->iv_size);
 516
 517	return 0;
 518}
 519
 520static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv,
 521			    struct dm_crypt_request *dmreq)
 522{
 523	struct scatterlist *sg;
 524	u8 *src;
 525	int r = 0;
 526
 527	if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
 528		sg = crypt_get_sg_data(cc, dmreq->sg_in);
 529		src = kmap_atomic(sg_page(sg));
 530		r = crypt_iv_lmk_one(cc, iv, dmreq, src + sg->offset);
 531		kunmap_atomic(src);
 532	} else
 533		memset(iv, 0, cc->iv_size);
 534
 535	return r;
 536}
 537
 538static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv,
 539			     struct dm_crypt_request *dmreq)
 540{
 541	struct scatterlist *sg;
 542	u8 *dst;
 543	int r;
 544
 545	if (bio_data_dir(dmreq->ctx->bio_in) == WRITE)
 546		return 0;
 547
 548	sg = crypt_get_sg_data(cc, dmreq->sg_out);
 549	dst = kmap_atomic(sg_page(sg));
 550	r = crypt_iv_lmk_one(cc, iv, dmreq, dst + sg->offset);
 551
 552	/* Tweak the first block of plaintext sector */
 553	if (!r)
 554		crypto_xor(dst + sg->offset, iv, cc->iv_size);
 555
 556	kunmap_atomic(dst);
 557	return r;
 558}
 559
 560static void crypt_iv_tcw_dtr(struct crypt_config *cc)
 561{
 562	struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
 563
 564	kfree_sensitive(tcw->iv_seed);
 565	tcw->iv_seed = NULL;
 566	kfree_sensitive(tcw->whitening);
 567	tcw->whitening = NULL;
 568
 569	if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm))
 570		crypto_free_shash(tcw->crc32_tfm);
 571	tcw->crc32_tfm = NULL;
 572}
 573
 574static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti,
 575			    const char *opts)
 576{
 577	struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
 578
 579	if (cc->sector_size != (1 << SECTOR_SHIFT)) {
 580		ti->error = "Unsupported sector size for TCW";
 581		return -EINVAL;
 582	}
 583
 584	if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) {
 585		ti->error = "Wrong key size for TCW";
 586		return -EINVAL;
 587	}
 588
 589	tcw->crc32_tfm = crypto_alloc_shash("crc32", 0, 0);
 
 590	if (IS_ERR(tcw->crc32_tfm)) {
 591		ti->error = "Error initializing CRC32 in TCW";
 592		return PTR_ERR(tcw->crc32_tfm);
 593	}
 594
 595	tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL);
 596	tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL);
 597	if (!tcw->iv_seed || !tcw->whitening) {
 598		crypt_iv_tcw_dtr(cc);
 599		ti->error = "Error allocating seed storage in TCW";
 600		return -ENOMEM;
 601	}
 602
 603	return 0;
 604}
 605
 606static int crypt_iv_tcw_init(struct crypt_config *cc)
 607{
 608	struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
 609	int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE;
 610
 611	memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size);
 612	memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size],
 613	       TCW_WHITENING_SIZE);
 614
 615	return 0;
 616}
 617
 618static int crypt_iv_tcw_wipe(struct crypt_config *cc)
 619{
 620	struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
 621
 622	memset(tcw->iv_seed, 0, cc->iv_size);
 623	memset(tcw->whitening, 0, TCW_WHITENING_SIZE);
 624
 625	return 0;
 626}
 627
 628static int crypt_iv_tcw_whitening(struct crypt_config *cc,
 629				  struct dm_crypt_request *dmreq,
 630				  u8 *data)
 631{
 632	struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
 633	__le64 sector = cpu_to_le64(dmreq->iv_sector);
 634	u8 buf[TCW_WHITENING_SIZE];
 635	SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm);
 636	int i, r;
 637
 638	/* xor whitening with sector number */
 639	crypto_xor_cpy(buf, tcw->whitening, (u8 *)&sector, 8);
 640	crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)&sector, 8);
 641
 642	/* calculate crc32 for every 32bit part and xor it */
 643	desc->tfm = tcw->crc32_tfm;
 644	for (i = 0; i < 4; i++) {
 645		r = crypto_shash_init(desc);
 646		if (r)
 647			goto out;
 648		r = crypto_shash_update(desc, &buf[i * 4], 4);
 649		if (r)
 650			goto out;
 651		r = crypto_shash_final(desc, &buf[i * 4]);
 652		if (r)
 653			goto out;
 654	}
 655	crypto_xor(&buf[0], &buf[12], 4);
 656	crypto_xor(&buf[4], &buf[8], 4);
 657
 658	/* apply whitening (8 bytes) to whole sector */
 659	for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++)
 660		crypto_xor(data + i * 8, buf, 8);
 661out:
 662	memzero_explicit(buf, sizeof(buf));
 663	return r;
 664}
 665
 666static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv,
 667			    struct dm_crypt_request *dmreq)
 668{
 669	struct scatterlist *sg;
 670	struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
 671	__le64 sector = cpu_to_le64(dmreq->iv_sector);
 672	u8 *src;
 673	int r = 0;
 674
 675	/* Remove whitening from ciphertext */
 676	if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) {
 677		sg = crypt_get_sg_data(cc, dmreq->sg_in);
 678		src = kmap_atomic(sg_page(sg));
 679		r = crypt_iv_tcw_whitening(cc, dmreq, src + sg->offset);
 680		kunmap_atomic(src);
 681	}
 682
 683	/* Calculate IV */
 684	crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)&sector, 8);
 685	if (cc->iv_size > 8)
 686		crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)&sector,
 687			       cc->iv_size - 8);
 688
 689	return r;
 690}
 691
 692static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv,
 693			     struct dm_crypt_request *dmreq)
 694{
 695	struct scatterlist *sg;
 696	u8 *dst;
 697	int r;
 698
 699	if (bio_data_dir(dmreq->ctx->bio_in) != WRITE)
 700		return 0;
 701
 702	/* Apply whitening on ciphertext */
 703	sg = crypt_get_sg_data(cc, dmreq->sg_out);
 704	dst = kmap_atomic(sg_page(sg));
 705	r = crypt_iv_tcw_whitening(cc, dmreq, dst + sg->offset);
 706	kunmap_atomic(dst);
 707
 708	return r;
 709}
 710
 711static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv,
 712				struct dm_crypt_request *dmreq)
 713{
 714	/* Used only for writes, there must be an additional space to store IV */
 715	get_random_bytes(iv, cc->iv_size);
 716	return 0;
 717}
 718
 719static int crypt_iv_eboiv_ctr(struct crypt_config *cc, struct dm_target *ti,
 720			    const char *opts)
 721{
 722	if (crypt_integrity_aead(cc)) {
 723		ti->error = "AEAD transforms not supported for EBOIV";
 724		return -EINVAL;
 725	}
 726
 727	if (crypto_skcipher_blocksize(any_tfm(cc)) != cc->iv_size) {
 728		ti->error = "Block size of EBOIV cipher does "
 729			    "not match IV size of block cipher";
 730		return -EINVAL;
 731	}
 732
 733	return 0;
 734}
 735
 736static int crypt_iv_eboiv_gen(struct crypt_config *cc, u8 *iv,
 737			    struct dm_crypt_request *dmreq)
 738{
 739	u8 buf[MAX_CIPHER_BLOCKSIZE] __aligned(__alignof__(__le64));
 740	struct skcipher_request *req;
 741	struct scatterlist src, dst;
 742	DECLARE_CRYPTO_WAIT(wait);
 
 743	int err;
 
 
 
 
 744
 745	req = skcipher_request_alloc(any_tfm(cc), GFP_NOIO);
 746	if (!req)
 747		return -ENOMEM;
 748
 
 
 
 749	memset(buf, 0, cc->iv_size);
 750	*(__le64 *)buf = cpu_to_le64(dmreq->iv_sector * cc->sector_size);
 751
 752	sg_init_one(&src, page_address(ZERO_PAGE(0)), cc->iv_size);
 753	sg_init_one(&dst, iv, cc->iv_size);
 754	skcipher_request_set_crypt(req, &src, &dst, cc->iv_size, buf);
 755	skcipher_request_set_callback(req, 0, crypto_req_done, &wait);
 756	err = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
 757	skcipher_request_free(req);
 758
 759	return err;
 760}
 761
 762static void crypt_iv_elephant_dtr(struct crypt_config *cc)
 763{
 764	struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
 765
 766	crypto_free_skcipher(elephant->tfm);
 767	elephant->tfm = NULL;
 768}
 769
 770static int crypt_iv_elephant_ctr(struct crypt_config *cc, struct dm_target *ti,
 771			    const char *opts)
 772{
 773	struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
 774	int r;
 775
 776	elephant->tfm = crypto_alloc_skcipher("ecb(aes)", 0, 0);
 
 777	if (IS_ERR(elephant->tfm)) {
 778		r = PTR_ERR(elephant->tfm);
 779		elephant->tfm = NULL;
 780		return r;
 781	}
 782
 783	r = crypt_iv_eboiv_ctr(cc, ti, NULL);
 784	if (r)
 785		crypt_iv_elephant_dtr(cc);
 786	return r;
 787}
 788
 789static void diffuser_disk_to_cpu(u32 *d, size_t n)
 790{
 791#ifndef __LITTLE_ENDIAN
 792	int i;
 793
 794	for (i = 0; i < n; i++)
 795		d[i] = le32_to_cpu((__le32)d[i]);
 796#endif
 797}
 798
 799static void diffuser_cpu_to_disk(__le32 *d, size_t n)
 800{
 801#ifndef __LITTLE_ENDIAN
 802	int i;
 803
 804	for (i = 0; i < n; i++)
 805		d[i] = cpu_to_le32((u32)d[i]);
 806#endif
 807}
 808
 809static void diffuser_a_decrypt(u32 *d, size_t n)
 810{
 811	int i, i1, i2, i3;
 812
 813	for (i = 0; i < 5; i++) {
 814		i1 = 0;
 815		i2 = n - 2;
 816		i3 = n - 5;
 817
 818		while (i1 < (n - 1)) {
 819			d[i1] += d[i2] ^ (d[i3] << 9 | d[i3] >> 23);
 820			i1++; i2++; i3++;
 821
 822			if (i3 >= n)
 823				i3 -= n;
 824
 825			d[i1] += d[i2] ^ d[i3];
 826			i1++; i2++; i3++;
 827
 828			if (i2 >= n)
 829				i2 -= n;
 830
 831			d[i1] += d[i2] ^ (d[i3] << 13 | d[i3] >> 19);
 832			i1++; i2++; i3++;
 833
 834			d[i1] += d[i2] ^ d[i3];
 835			i1++; i2++; i3++;
 836		}
 837	}
 838}
 839
 840static void diffuser_a_encrypt(u32 *d, size_t n)
 841{
 842	int i, i1, i2, i3;
 843
 844	for (i = 0; i < 5; i++) {
 845		i1 = n - 1;
 846		i2 = n - 2 - 1;
 847		i3 = n - 5 - 1;
 848
 849		while (i1 > 0) {
 850			d[i1] -= d[i2] ^ d[i3];
 851			i1--; i2--; i3--;
 852
 853			d[i1] -= d[i2] ^ (d[i3] << 13 | d[i3] >> 19);
 854			i1--; i2--; i3--;
 855
 856			if (i2 < 0)
 857				i2 += n;
 858
 859			d[i1] -= d[i2] ^ d[i3];
 860			i1--; i2--; i3--;
 861
 862			if (i3 < 0)
 863				i3 += n;
 864
 865			d[i1] -= d[i2] ^ (d[i3] << 9 | d[i3] >> 23);
 866			i1--; i2--; i3--;
 867		}
 868	}
 869}
 870
 871static void diffuser_b_decrypt(u32 *d, size_t n)
 872{
 873	int i, i1, i2, i3;
 874
 875	for (i = 0; i < 3; i++) {
 876		i1 = 0;
 877		i2 = 2;
 878		i3 = 5;
 879
 880		while (i1 < (n - 1)) {
 881			d[i1] += d[i2] ^ d[i3];
 882			i1++; i2++; i3++;
 883
 884			d[i1] += d[i2] ^ (d[i3] << 10 | d[i3] >> 22);
 885			i1++; i2++; i3++;
 886
 887			if (i2 >= n)
 888				i2 -= n;
 889
 890			d[i1] += d[i2] ^ d[i3];
 891			i1++; i2++; i3++;
 892
 893			if (i3 >= n)
 894				i3 -= n;
 895
 896			d[i1] += d[i2] ^ (d[i3] << 25 | d[i3] >> 7);
 897			i1++; i2++; i3++;
 898		}
 899	}
 900}
 901
 902static void diffuser_b_encrypt(u32 *d, size_t n)
 903{
 904	int i, i1, i2, i3;
 905
 906	for (i = 0; i < 3; i++) {
 907		i1 = n - 1;
 908		i2 = 2 - 1;
 909		i3 = 5 - 1;
 910
 911		while (i1 > 0) {
 912			d[i1] -= d[i2] ^ (d[i3] << 25 | d[i3] >> 7);
 913			i1--; i2--; i3--;
 914
 915			if (i3 < 0)
 916				i3 += n;
 917
 918			d[i1] -= d[i2] ^ d[i3];
 919			i1--; i2--; i3--;
 920
 921			if (i2 < 0)
 922				i2 += n;
 923
 924			d[i1] -= d[i2] ^ (d[i3] << 10 | d[i3] >> 22);
 925			i1--; i2--; i3--;
 926
 927			d[i1] -= d[i2] ^ d[i3];
 928			i1--; i2--; i3--;
 929		}
 930	}
 931}
 932
 933static int crypt_iv_elephant(struct crypt_config *cc, struct dm_crypt_request *dmreq)
 934{
 935	struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
 936	u8 *es, *ks, *data, *data2, *data_offset;
 937	struct skcipher_request *req;
 938	struct scatterlist *sg, *sg2, src, dst;
 939	DECLARE_CRYPTO_WAIT(wait);
 940	int i, r;
 941
 942	req = skcipher_request_alloc(elephant->tfm, GFP_NOIO);
 943	es = kzalloc(16, GFP_NOIO); /* Key for AES */
 944	ks = kzalloc(32, GFP_NOIO); /* Elephant sector key */
 945
 946	if (!req || !es || !ks) {
 947		r = -ENOMEM;
 948		goto out;
 949	}
 950
 951	*(__le64 *)es = cpu_to_le64(dmreq->iv_sector * cc->sector_size);
 952
 953	/* E(Ks, e(s)) */
 954	sg_init_one(&src, es, 16);
 955	sg_init_one(&dst, ks, 16);
 956	skcipher_request_set_crypt(req, &src, &dst, 16, NULL);
 957	skcipher_request_set_callback(req, 0, crypto_req_done, &wait);
 958	r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
 959	if (r)
 960		goto out;
 961
 962	/* E(Ks, e'(s)) */
 963	es[15] = 0x80;
 964	sg_init_one(&dst, &ks[16], 16);
 965	r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
 966	if (r)
 967		goto out;
 968
 969	sg = crypt_get_sg_data(cc, dmreq->sg_out);
 970	data = kmap_atomic(sg_page(sg));
 971	data_offset = data + sg->offset;
 972
 973	/* Cannot modify original bio, copy to sg_out and apply Elephant to it */
 974	if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
 975		sg2 = crypt_get_sg_data(cc, dmreq->sg_in);
 976		data2 = kmap_atomic(sg_page(sg2));
 977		memcpy(data_offset, data2 + sg2->offset, cc->sector_size);
 978		kunmap_atomic(data2);
 979	}
 980
 981	if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) {
 982		diffuser_disk_to_cpu((u32*)data_offset, cc->sector_size / sizeof(u32));
 983		diffuser_b_decrypt((u32*)data_offset, cc->sector_size / sizeof(u32));
 984		diffuser_a_decrypt((u32*)data_offset, cc->sector_size / sizeof(u32));
 985		diffuser_cpu_to_disk((__le32*)data_offset, cc->sector_size / sizeof(u32));
 986	}
 987
 988	for (i = 0; i < (cc->sector_size / 32); i++)
 989		crypto_xor(data_offset + i * 32, ks, 32);
 990
 991	if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
 992		diffuser_disk_to_cpu((u32*)data_offset, cc->sector_size / sizeof(u32));
 993		diffuser_a_encrypt((u32*)data_offset, cc->sector_size / sizeof(u32));
 994		diffuser_b_encrypt((u32*)data_offset, cc->sector_size / sizeof(u32));
 995		diffuser_cpu_to_disk((__le32*)data_offset, cc->sector_size / sizeof(u32));
 996	}
 997
 998	kunmap_atomic(data);
 999out:
1000	kfree_sensitive(ks);
1001	kfree_sensitive(es);
1002	skcipher_request_free(req);
1003	return r;
1004}
1005
1006static int crypt_iv_elephant_gen(struct crypt_config *cc, u8 *iv,
1007			    struct dm_crypt_request *dmreq)
1008{
1009	int r;
1010
1011	if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
1012		r = crypt_iv_elephant(cc, dmreq);
1013		if (r)
1014			return r;
1015	}
1016
1017	return crypt_iv_eboiv_gen(cc, iv, dmreq);
1018}
1019
1020static int crypt_iv_elephant_post(struct crypt_config *cc, u8 *iv,
1021				  struct dm_crypt_request *dmreq)
1022{
1023	if (bio_data_dir(dmreq->ctx->bio_in) != WRITE)
1024		return crypt_iv_elephant(cc, dmreq);
1025
1026	return 0;
1027}
1028
1029static int crypt_iv_elephant_init(struct crypt_config *cc)
1030{
1031	struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
1032	int key_offset = cc->key_size - cc->key_extra_size;
1033
1034	return crypto_skcipher_setkey(elephant->tfm, &cc->key[key_offset], cc->key_extra_size);
1035}
1036
1037static int crypt_iv_elephant_wipe(struct crypt_config *cc)
1038{
1039	struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
1040	u8 key[ELEPHANT_MAX_KEY_SIZE];
1041
1042	memset(key, 0, cc->key_extra_size);
1043	return crypto_skcipher_setkey(elephant->tfm, key, cc->key_extra_size);
1044}
1045
1046static const struct crypt_iv_operations crypt_iv_plain_ops = {
1047	.generator = crypt_iv_plain_gen
1048};
1049
1050static const struct crypt_iv_operations crypt_iv_plain64_ops = {
1051	.generator = crypt_iv_plain64_gen
1052};
1053
1054static const struct crypt_iv_operations crypt_iv_plain64be_ops = {
1055	.generator = crypt_iv_plain64be_gen
1056};
1057
1058static const struct crypt_iv_operations crypt_iv_essiv_ops = {
1059	.generator = crypt_iv_essiv_gen
1060};
1061
1062static const struct crypt_iv_operations crypt_iv_benbi_ops = {
1063	.ctr	   = crypt_iv_benbi_ctr,
1064	.dtr	   = crypt_iv_benbi_dtr,
1065	.generator = crypt_iv_benbi_gen
1066};
1067
1068static const struct crypt_iv_operations crypt_iv_null_ops = {
1069	.generator = crypt_iv_null_gen
1070};
1071
1072static const struct crypt_iv_operations crypt_iv_lmk_ops = {
1073	.ctr	   = crypt_iv_lmk_ctr,
1074	.dtr	   = crypt_iv_lmk_dtr,
1075	.init	   = crypt_iv_lmk_init,
1076	.wipe	   = crypt_iv_lmk_wipe,
1077	.generator = crypt_iv_lmk_gen,
1078	.post	   = crypt_iv_lmk_post
1079};
1080
1081static const struct crypt_iv_operations crypt_iv_tcw_ops = {
1082	.ctr	   = crypt_iv_tcw_ctr,
1083	.dtr	   = crypt_iv_tcw_dtr,
1084	.init	   = crypt_iv_tcw_init,
1085	.wipe	   = crypt_iv_tcw_wipe,
1086	.generator = crypt_iv_tcw_gen,
1087	.post	   = crypt_iv_tcw_post
1088};
1089
1090static struct crypt_iv_operations crypt_iv_random_ops = {
1091	.generator = crypt_iv_random_gen
1092};
1093
1094static struct crypt_iv_operations crypt_iv_eboiv_ops = {
1095	.ctr	   = crypt_iv_eboiv_ctr,
1096	.generator = crypt_iv_eboiv_gen
1097};
1098
1099static struct crypt_iv_operations crypt_iv_elephant_ops = {
1100	.ctr	   = crypt_iv_elephant_ctr,
1101	.dtr	   = crypt_iv_elephant_dtr,
1102	.init	   = crypt_iv_elephant_init,
1103	.wipe	   = crypt_iv_elephant_wipe,
1104	.generator = crypt_iv_elephant_gen,
1105	.post	   = crypt_iv_elephant_post
1106};
1107
1108/*
1109 * Integrity extensions
1110 */
1111static bool crypt_integrity_aead(struct crypt_config *cc)
1112{
1113	return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags);
1114}
1115
1116static bool crypt_integrity_hmac(struct crypt_config *cc)
1117{
1118	return crypt_integrity_aead(cc) && cc->key_mac_size;
1119}
1120
1121/* Get sg containing data */
1122static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc,
1123					     struct scatterlist *sg)
1124{
1125	if (unlikely(crypt_integrity_aead(cc)))
1126		return &sg[2];
1127
1128	return sg;
1129}
1130
1131static int dm_crypt_integrity_io_alloc(struct dm_crypt_io *io, struct bio *bio)
1132{
1133	struct bio_integrity_payload *bip;
1134	unsigned int tag_len;
1135	int ret;
1136
1137	if (!bio_sectors(bio) || !io->cc->on_disk_tag_size)
1138		return 0;
1139
1140	bip = bio_integrity_alloc(bio, GFP_NOIO, 1);
1141	if (IS_ERR(bip))
1142		return PTR_ERR(bip);
1143
1144	tag_len = io->cc->on_disk_tag_size * (bio_sectors(bio) >> io->cc->sector_shift);
1145
1146	bip->bip_iter.bi_size = tag_len;
1147	bip->bip_iter.bi_sector = io->cc->start + io->sector;
1148
1149	ret = bio_integrity_add_page(bio, virt_to_page(io->integrity_metadata),
1150				     tag_len, offset_in_page(io->integrity_metadata));
1151	if (unlikely(ret != tag_len))
1152		return -ENOMEM;
1153
1154	return 0;
1155}
1156
1157static int crypt_integrity_ctr(struct crypt_config *cc, struct dm_target *ti)
1158{
1159#ifdef CONFIG_BLK_DEV_INTEGRITY
1160	struct blk_integrity *bi = blk_get_integrity(cc->dev->bdev->bd_disk);
1161	struct mapped_device *md = dm_table_get_md(ti->table);
1162
1163	/* From now we require underlying device with our integrity profile */
1164	if (!bi || strcasecmp(bi->profile->name, "DM-DIF-EXT-TAG")) {
1165		ti->error = "Integrity profile not supported.";
1166		return -EINVAL;
1167	}
1168
1169	if (bi->tag_size != cc->on_disk_tag_size ||
1170	    bi->tuple_size != cc->on_disk_tag_size) {
1171		ti->error = "Integrity profile tag size mismatch.";
1172		return -EINVAL;
1173	}
1174	if (1 << bi->interval_exp != cc->sector_size) {
1175		ti->error = "Integrity profile sector size mismatch.";
1176		return -EINVAL;
1177	}
1178
1179	if (crypt_integrity_aead(cc)) {
1180		cc->integrity_tag_size = cc->on_disk_tag_size - cc->integrity_iv_size;
1181		DMDEBUG("%s: Integrity AEAD, tag size %u, IV size %u.", dm_device_name(md),
1182		       cc->integrity_tag_size, cc->integrity_iv_size);
1183
1184		if (crypto_aead_setauthsize(any_tfm_aead(cc), cc->integrity_tag_size)) {
1185			ti->error = "Integrity AEAD auth tag size is not supported.";
1186			return -EINVAL;
1187		}
1188	} else if (cc->integrity_iv_size)
1189		DMDEBUG("%s: Additional per-sector space %u bytes for IV.", dm_device_name(md),
1190		       cc->integrity_iv_size);
1191
1192	if ((cc->integrity_tag_size + cc->integrity_iv_size) != bi->tag_size) {
1193		ti->error = "Not enough space for integrity tag in the profile.";
1194		return -EINVAL;
1195	}
1196
1197	return 0;
1198#else
1199	ti->error = "Integrity profile not supported.";
1200	return -EINVAL;
1201#endif
1202}
1203
1204static void crypt_convert_init(struct crypt_config *cc,
1205			       struct convert_context *ctx,
1206			       struct bio *bio_out, struct bio *bio_in,
1207			       sector_t sector)
1208{
1209	ctx->bio_in = bio_in;
1210	ctx->bio_out = bio_out;
1211	if (bio_in)
1212		ctx->iter_in = bio_in->bi_iter;
1213	if (bio_out)
1214		ctx->iter_out = bio_out->bi_iter;
1215	ctx->cc_sector = sector + cc->iv_offset;
1216	init_completion(&ctx->restart);
1217}
1218
1219static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc,
1220					     void *req)
1221{
1222	return (struct dm_crypt_request *)((char *)req + cc->dmreq_start);
1223}
1224
1225static void *req_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq)
1226{
1227	return (void *)((char *)dmreq - cc->dmreq_start);
1228}
1229
1230static u8 *iv_of_dmreq(struct crypt_config *cc,
1231		       struct dm_crypt_request *dmreq)
1232{
1233	if (crypt_integrity_aead(cc))
1234		return (u8 *)ALIGN((unsigned long)(dmreq + 1),
1235			crypto_aead_alignmask(any_tfm_aead(cc)) + 1);
1236	else
1237		return (u8 *)ALIGN((unsigned long)(dmreq + 1),
1238			crypto_skcipher_alignmask(any_tfm(cc)) + 1);
1239}
1240
1241static u8 *org_iv_of_dmreq(struct crypt_config *cc,
1242		       struct dm_crypt_request *dmreq)
1243{
1244	return iv_of_dmreq(cc, dmreq) + cc->iv_size;
1245}
1246
1247static __le64 *org_sector_of_dmreq(struct crypt_config *cc,
1248		       struct dm_crypt_request *dmreq)
1249{
1250	u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + cc->iv_size;
 
1251	return (__le64 *) ptr;
1252}
1253
1254static unsigned int *org_tag_of_dmreq(struct crypt_config *cc,
1255		       struct dm_crypt_request *dmreq)
1256{
1257	u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size +
1258		  cc->iv_size + sizeof(uint64_t);
1259	return (unsigned int*)ptr;
 
1260}
1261
1262static void *tag_from_dmreq(struct crypt_config *cc,
1263				struct dm_crypt_request *dmreq)
1264{
1265	struct convert_context *ctx = dmreq->ctx;
1266	struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
1267
1268	return &io->integrity_metadata[*org_tag_of_dmreq(cc, dmreq) *
1269		cc->on_disk_tag_size];
1270}
1271
1272static void *iv_tag_from_dmreq(struct crypt_config *cc,
1273			       struct dm_crypt_request *dmreq)
1274{
1275	return tag_from_dmreq(cc, dmreq) + cc->integrity_tag_size;
1276}
1277
1278static int crypt_convert_block_aead(struct crypt_config *cc,
1279				     struct convert_context *ctx,
1280				     struct aead_request *req,
1281				     unsigned int tag_offset)
1282{
1283	struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in);
1284	struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out);
1285	struct dm_crypt_request *dmreq;
1286	u8 *iv, *org_iv, *tag_iv, *tag;
1287	__le64 *sector;
1288	int r = 0;
1289
1290	BUG_ON(cc->integrity_iv_size && cc->integrity_iv_size != cc->iv_size);
1291
1292	/* Reject unexpected unaligned bio. */
1293	if (unlikely(bv_in.bv_len & (cc->sector_size - 1)))
1294		return -EIO;
1295
1296	dmreq = dmreq_of_req(cc, req);
1297	dmreq->iv_sector = ctx->cc_sector;
1298	if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
1299		dmreq->iv_sector >>= cc->sector_shift;
1300	dmreq->ctx = ctx;
1301
1302	*org_tag_of_dmreq(cc, dmreq) = tag_offset;
1303
1304	sector = org_sector_of_dmreq(cc, dmreq);
1305	*sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset);
1306
1307	iv = iv_of_dmreq(cc, dmreq);
1308	org_iv = org_iv_of_dmreq(cc, dmreq);
1309	tag = tag_from_dmreq(cc, dmreq);
1310	tag_iv = iv_tag_from_dmreq(cc, dmreq);
1311
1312	/* AEAD request:
1313	 *  |----- AAD -------|------ DATA -------|-- AUTH TAG --|
1314	 *  | (authenticated) | (auth+encryption) |              |
1315	 *  | sector_LE |  IV |  sector in/out    |  tag in/out  |
1316	 */
1317	sg_init_table(dmreq->sg_in, 4);
1318	sg_set_buf(&dmreq->sg_in[0], sector, sizeof(uint64_t));
1319	sg_set_buf(&dmreq->sg_in[1], org_iv, cc->iv_size);
1320	sg_set_page(&dmreq->sg_in[2], bv_in.bv_page, cc->sector_size, bv_in.bv_offset);
1321	sg_set_buf(&dmreq->sg_in[3], tag, cc->integrity_tag_size);
1322
1323	sg_init_table(dmreq->sg_out, 4);
1324	sg_set_buf(&dmreq->sg_out[0], sector, sizeof(uint64_t));
1325	sg_set_buf(&dmreq->sg_out[1], org_iv, cc->iv_size);
1326	sg_set_page(&dmreq->sg_out[2], bv_out.bv_page, cc->sector_size, bv_out.bv_offset);
1327	sg_set_buf(&dmreq->sg_out[3], tag, cc->integrity_tag_size);
1328
1329	if (cc->iv_gen_ops) {
1330		/* For READs use IV stored in integrity metadata */
1331		if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) {
1332			memcpy(org_iv, tag_iv, cc->iv_size);
1333		} else {
1334			r = cc->iv_gen_ops->generator(cc, org_iv, dmreq);
1335			if (r < 0)
1336				return r;
1337			/* Store generated IV in integrity metadata */
1338			if (cc->integrity_iv_size)
1339				memcpy(tag_iv, org_iv, cc->iv_size);
1340		}
1341		/* Working copy of IV, to be modified in crypto API */
1342		memcpy(iv, org_iv, cc->iv_size);
1343	}
1344
1345	aead_request_set_ad(req, sizeof(uint64_t) + cc->iv_size);
1346	if (bio_data_dir(ctx->bio_in) == WRITE) {
1347		aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out,
1348				       cc->sector_size, iv);
1349		r = crypto_aead_encrypt(req);
1350		if (cc->integrity_tag_size + cc->integrity_iv_size != cc->on_disk_tag_size)
1351			memset(tag + cc->integrity_tag_size + cc->integrity_iv_size, 0,
1352			       cc->on_disk_tag_size - (cc->integrity_tag_size + cc->integrity_iv_size));
1353	} else {
1354		aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out,
1355				       cc->sector_size + cc->integrity_tag_size, iv);
1356		r = crypto_aead_decrypt(req);
1357	}
1358
1359	if (r == -EBADMSG) {
1360		char b[BDEVNAME_SIZE];
1361		DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu", bio_devname(ctx->bio_in, b),
1362			    (unsigned long long)le64_to_cpu(*sector));
 
 
 
 
 
 
1363	}
1364
1365	if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
1366		r = cc->iv_gen_ops->post(cc, org_iv, dmreq);
1367
1368	bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size);
1369	bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size);
1370
1371	return r;
1372}
1373
1374static int crypt_convert_block_skcipher(struct crypt_config *cc,
1375					struct convert_context *ctx,
1376					struct skcipher_request *req,
1377					unsigned int tag_offset)
1378{
1379	struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in);
1380	struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out);
1381	struct scatterlist *sg_in, *sg_out;
1382	struct dm_crypt_request *dmreq;
1383	u8 *iv, *org_iv, *tag_iv;
1384	__le64 *sector;
1385	int r = 0;
1386
1387	/* Reject unexpected unaligned bio. */
1388	if (unlikely(bv_in.bv_len & (cc->sector_size - 1)))
1389		return -EIO;
1390
1391	dmreq = dmreq_of_req(cc, req);
1392	dmreq->iv_sector = ctx->cc_sector;
1393	if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
1394		dmreq->iv_sector >>= cc->sector_shift;
1395	dmreq->ctx = ctx;
1396
1397	*org_tag_of_dmreq(cc, dmreq) = tag_offset;
1398
1399	iv = iv_of_dmreq(cc, dmreq);
1400	org_iv = org_iv_of_dmreq(cc, dmreq);
1401	tag_iv = iv_tag_from_dmreq(cc, dmreq);
1402
1403	sector = org_sector_of_dmreq(cc, dmreq);
1404	*sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset);
1405
1406	/* For skcipher we use only the first sg item */
1407	sg_in  = &dmreq->sg_in[0];
1408	sg_out = &dmreq->sg_out[0];
1409
1410	sg_init_table(sg_in, 1);
1411	sg_set_page(sg_in, bv_in.bv_page, cc->sector_size, bv_in.bv_offset);
1412
1413	sg_init_table(sg_out, 1);
1414	sg_set_page(sg_out, bv_out.bv_page, cc->sector_size, bv_out.bv_offset);
1415
1416	if (cc->iv_gen_ops) {
1417		/* For READs use IV stored in integrity metadata */
1418		if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) {
1419			memcpy(org_iv, tag_iv, cc->integrity_iv_size);
1420		} else {
1421			r = cc->iv_gen_ops->generator(cc, org_iv, dmreq);
1422			if (r < 0)
1423				return r;
1424			/* Data can be already preprocessed in generator */
1425			if (test_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags))
1426				sg_in = sg_out;
1427			/* Store generated IV in integrity metadata */
1428			if (cc->integrity_iv_size)
1429				memcpy(tag_iv, org_iv, cc->integrity_iv_size);
1430		}
1431		/* Working copy of IV, to be modified in crypto API */
1432		memcpy(iv, org_iv, cc->iv_size);
1433	}
1434
1435	skcipher_request_set_crypt(req, sg_in, sg_out, cc->sector_size, iv);
1436
1437	if (bio_data_dir(ctx->bio_in) == WRITE)
1438		r = crypto_skcipher_encrypt(req);
1439	else
1440		r = crypto_skcipher_decrypt(req);
1441
1442	if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
1443		r = cc->iv_gen_ops->post(cc, org_iv, dmreq);
1444
1445	bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size);
1446	bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size);
1447
1448	return r;
1449}
1450
1451static void kcryptd_async_done(struct crypto_async_request *async_req,
1452			       int error);
1453
1454static void crypt_alloc_req_skcipher(struct crypt_config *cc,
1455				     struct convert_context *ctx)
1456{
1457	unsigned key_index = ctx->cc_sector & (cc->tfms_count - 1);
1458
1459	if (!ctx->r.req)
1460		ctx->r.req = mempool_alloc(&cc->req_pool, GFP_NOIO);
 
 
 
1461
1462	skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]);
1463
1464	/*
1465	 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs
1466	 * requests if driver request queue is full.
1467	 */
1468	skcipher_request_set_callback(ctx->r.req,
1469	    CRYPTO_TFM_REQ_MAY_BACKLOG,
1470	    kcryptd_async_done, dmreq_of_req(cc, ctx->r.req));
 
 
1471}
1472
1473static void crypt_alloc_req_aead(struct crypt_config *cc,
1474				 struct convert_context *ctx)
1475{
1476	if (!ctx->r.req_aead)
1477		ctx->r.req_aead = mempool_alloc(&cc->req_pool, GFP_NOIO);
 
 
 
1478
1479	aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]);
1480
1481	/*
1482	 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs
1483	 * requests if driver request queue is full.
1484	 */
1485	aead_request_set_callback(ctx->r.req_aead,
1486	    CRYPTO_TFM_REQ_MAY_BACKLOG,
1487	    kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead));
 
 
1488}
1489
1490static void crypt_alloc_req(struct crypt_config *cc,
1491			    struct convert_context *ctx)
1492{
1493	if (crypt_integrity_aead(cc))
1494		crypt_alloc_req_aead(cc, ctx);
1495	else
1496		crypt_alloc_req_skcipher(cc, ctx);
1497}
1498
1499static void crypt_free_req_skcipher(struct crypt_config *cc,
1500				    struct skcipher_request *req, struct bio *base_bio)
1501{
1502	struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size);
1503
1504	if ((struct skcipher_request *)(io + 1) != req)
1505		mempool_free(req, &cc->req_pool);
1506}
1507
1508static void crypt_free_req_aead(struct crypt_config *cc,
1509				struct aead_request *req, struct bio *base_bio)
1510{
1511	struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size);
1512
1513	if ((struct aead_request *)(io + 1) != req)
1514		mempool_free(req, &cc->req_pool);
1515}
1516
1517static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio)
1518{
1519	if (crypt_integrity_aead(cc))
1520		crypt_free_req_aead(cc, req, base_bio);
1521	else
1522		crypt_free_req_skcipher(cc, req, base_bio);
1523}
1524
1525/*
1526 * Encrypt / decrypt data from one bio to another one (can be the same one)
1527 */
1528static blk_status_t crypt_convert(struct crypt_config *cc,
1529			 struct convert_context *ctx, bool atomic)
1530{
1531	unsigned int tag_offset = 0;
1532	unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT;
1533	int r;
1534
1535	atomic_set(&ctx->cc_pending, 1);
 
 
 
 
 
 
1536
1537	while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) {
1538
1539		crypt_alloc_req(cc, ctx);
 
 
 
 
 
1540		atomic_inc(&ctx->cc_pending);
1541
1542		if (crypt_integrity_aead(cc))
1543			r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, tag_offset);
1544		else
1545			r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, tag_offset);
1546
1547		switch (r) {
1548		/*
1549		 * The request was queued by a crypto driver
1550		 * but the driver request queue is full, let's wait.
1551		 */
1552		case -EBUSY:
1553			wait_for_completion(&ctx->restart);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1554			reinit_completion(&ctx->restart);
1555			fallthrough;
1556		/*
1557		 * The request is queued and processed asynchronously,
1558		 * completion function kcryptd_async_done() will be called.
1559		 */
1560		case -EINPROGRESS:
1561			ctx->r.req = NULL;
1562			ctx->cc_sector += sector_step;
1563			tag_offset++;
1564			continue;
1565		/*
1566		 * The request was already processed (synchronously).
1567		 */
1568		case 0:
1569			atomic_dec(&ctx->cc_pending);
1570			ctx->cc_sector += sector_step;
1571			tag_offset++;
1572			if (!atomic)
1573				cond_resched();
1574			continue;
1575		/*
1576		 * There was a data integrity error.
1577		 */
1578		case -EBADMSG:
1579			atomic_dec(&ctx->cc_pending);
1580			return BLK_STS_PROTECTION;
1581		/*
1582		 * There was an error while processing the request.
1583		 */
1584		default:
1585			atomic_dec(&ctx->cc_pending);
1586			return BLK_STS_IOERR;
1587		}
1588	}
1589
1590	return 0;
1591}
1592
1593static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone);
1594
1595/*
1596 * Generate a new unfragmented bio with the given size
1597 * This should never violate the device limitations (but only because
1598 * max_segment_size is being constrained to PAGE_SIZE).
1599 *
1600 * This function may be called concurrently. If we allocate from the mempool
1601 * concurrently, there is a possibility of deadlock. For example, if we have
1602 * mempool of 256 pages, two processes, each wanting 256, pages allocate from
1603 * the mempool concurrently, it may deadlock in a situation where both processes
1604 * have allocated 128 pages and the mempool is exhausted.
1605 *
1606 * In order to avoid this scenario we allocate the pages under a mutex.
1607 *
1608 * In order to not degrade performance with excessive locking, we try
1609 * non-blocking allocations without a mutex first but on failure we fallback
1610 * to blocking allocations with a mutex.
 
 
 
1611 */
1612static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned size)
1613{
1614	struct crypt_config *cc = io->cc;
1615	struct bio *clone;
1616	unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
1617	gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM;
1618	unsigned i, len, remaining_size;
1619	struct page *page;
1620
1621retry:
1622	if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM))
1623		mutex_lock(&cc->bio_alloc_lock);
1624
1625	clone = bio_alloc_bioset(GFP_NOIO, nr_iovecs, &cc->bs);
1626	if (!clone)
1627		goto out;
1628
1629	clone_init(io, clone);
1630
1631	remaining_size = size;
1632
1633	for (i = 0; i < nr_iovecs; i++) {
1634		page = mempool_alloc(&cc->page_pool, gfp_mask);
1635		if (!page) {
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1636			crypt_free_buffer_pages(cc, clone);
1637			bio_put(clone);
1638			gfp_mask |= __GFP_DIRECT_RECLAIM;
 
1639			goto retry;
1640		}
1641
1642		len = (remaining_size > PAGE_SIZE) ? PAGE_SIZE : remaining_size;
1643
1644		bio_add_page(clone, page, len, 0);
1645
1646		remaining_size -= len;
1647	}
1648
1649	/* Allocate space for integrity tags */
1650	if (dm_crypt_integrity_io_alloc(io, clone)) {
1651		crypt_free_buffer_pages(cc, clone);
1652		bio_put(clone);
1653		clone = NULL;
1654	}
1655out:
1656	if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM))
1657		mutex_unlock(&cc->bio_alloc_lock);
1658
1659	return clone;
1660}
1661
1662static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone)
1663{
1664	struct bio_vec *bv;
1665	struct bvec_iter_all iter_all;
1666
1667	bio_for_each_segment_all(bv, clone, iter_all) {
1668		BUG_ON(!bv->bv_page);
1669		mempool_free(bv->bv_page, &cc->page_pool);
 
 
 
 
 
 
 
1670	}
1671}
1672
1673static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc,
1674			  struct bio *bio, sector_t sector)
1675{
1676	io->cc = cc;
1677	io->base_bio = bio;
1678	io->sector = sector;
1679	io->error = 0;
 
 
1680	io->ctx.r.req = NULL;
1681	io->integrity_metadata = NULL;
1682	io->integrity_metadata_from_pool = false;
1683	atomic_set(&io->io_pending, 0);
1684}
1685
1686static void crypt_inc_pending(struct dm_crypt_io *io)
1687{
1688	atomic_inc(&io->io_pending);
1689}
1690
 
 
1691/*
1692 * One of the bios was finished. Check for completion of
1693 * the whole request and correctly clean up the buffer.
1694 */
1695static void crypt_dec_pending(struct dm_crypt_io *io)
1696{
1697	struct crypt_config *cc = io->cc;
1698	struct bio *base_bio = io->base_bio;
1699	blk_status_t error = io->error;
1700
1701	if (!atomic_dec_and_test(&io->io_pending))
1702		return;
1703
 
 
 
 
 
 
 
 
 
1704	if (io->ctx.r.req)
1705		crypt_free_req(cc, io->ctx.r.req, base_bio);
1706
1707	if (unlikely(io->integrity_metadata_from_pool))
1708		mempool_free(io->integrity_metadata, &io->cc->tag_pool);
1709	else
1710		kfree(io->integrity_metadata);
1711
1712	base_bio->bi_status = error;
 
1713	bio_endio(base_bio);
1714}
1715
1716/*
1717 * kcryptd/kcryptd_io:
1718 *
1719 * Needed because it would be very unwise to do decryption in an
1720 * interrupt context.
1721 *
1722 * kcryptd performs the actual encryption or decryption.
1723 *
1724 * kcryptd_io performs the IO submission.
1725 *
1726 * They must be separated as otherwise the final stages could be
1727 * starved by new requests which can block in the first stages due
1728 * to memory allocation.
1729 *
1730 * The work is done per CPU global for all dm-crypt instances.
1731 * They should not depend on each other and do not block.
1732 */
1733static void crypt_endio(struct bio *clone)
1734{
1735	struct dm_crypt_io *io = clone->bi_private;
1736	struct crypt_config *cc = io->cc;
1737	unsigned rw = bio_data_dir(clone);
1738	blk_status_t error;
 
 
 
 
 
1739
1740	/*
1741	 * free the processed pages
1742	 */
1743	if (rw == WRITE)
1744		crypt_free_buffer_pages(cc, clone);
1745
1746	error = clone->bi_status;
1747	bio_put(clone);
1748
1749	if (rw == READ && !error) {
1750		kcryptd_queue_crypt(io);
1751		return;
1752	}
1753
1754	if (unlikely(error))
1755		io->error = error;
1756
1757	crypt_dec_pending(io);
1758}
1759
1760static void clone_init(struct dm_crypt_io *io, struct bio *clone)
1761{
1762	struct crypt_config *cc = io->cc;
1763
1764	clone->bi_private = io;
1765	clone->bi_end_io  = crypt_endio;
1766	bio_set_dev(clone, cc->dev->bdev);
1767	clone->bi_opf	  = io->base_bio->bi_opf;
1768}
1769
1770static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
1771{
1772	struct crypt_config *cc = io->cc;
1773	struct bio *clone;
1774
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1775	/*
1776	 * We need the original biovec array in order to decrypt
1777	 * the whole bio data *afterwards* -- thanks to immutable
1778	 * biovecs we don't need to worry about the block layer
1779	 * modifying the biovec array; so leverage bio_clone_fast().
1780	 */
1781	clone = bio_clone_fast(io->base_bio, gfp, &cc->bs);
1782	if (!clone)
1783		return 1;
 
 
1784
1785	crypt_inc_pending(io);
1786
1787	clone_init(io, clone);
1788	clone->bi_iter.bi_sector = cc->start + io->sector;
1789
1790	if (dm_crypt_integrity_io_alloc(io, clone)) {
1791		crypt_dec_pending(io);
1792		bio_put(clone);
1793		return 1;
1794	}
1795
1796	submit_bio_noacct(clone);
1797	return 0;
1798}
1799
1800static void kcryptd_io_read_work(struct work_struct *work)
1801{
1802	struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
1803
1804	crypt_inc_pending(io);
1805	if (kcryptd_io_read(io, GFP_NOIO))
1806		io->error = BLK_STS_RESOURCE;
1807	crypt_dec_pending(io);
1808}
1809
1810static void kcryptd_queue_read(struct dm_crypt_io *io)
1811{
1812	struct crypt_config *cc = io->cc;
1813
1814	INIT_WORK(&io->work, kcryptd_io_read_work);
1815	queue_work(cc->io_queue, &io->work);
1816}
1817
1818static void kcryptd_io_write(struct dm_crypt_io *io)
1819{
1820	struct bio *clone = io->ctx.bio_out;
1821
1822	submit_bio_noacct(clone);
1823}
1824
1825#define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node)
1826
1827static int dmcrypt_write(void *data)
1828{
1829	struct crypt_config *cc = data;
1830	struct dm_crypt_io *io;
1831
1832	while (1) {
1833		struct rb_root write_tree;
1834		struct blk_plug plug;
1835
1836		spin_lock_irq(&cc->write_thread_lock);
1837continue_locked:
1838
1839		if (!RB_EMPTY_ROOT(&cc->write_tree))
1840			goto pop_from_list;
1841
1842		set_current_state(TASK_INTERRUPTIBLE);
1843
1844		spin_unlock_irq(&cc->write_thread_lock);
1845
1846		if (unlikely(kthread_should_stop())) {
1847			set_current_state(TASK_RUNNING);
1848			break;
1849		}
1850
1851		schedule();
1852
1853		set_current_state(TASK_RUNNING);
1854		spin_lock_irq(&cc->write_thread_lock);
1855		goto continue_locked;
1856
1857pop_from_list:
1858		write_tree = cc->write_tree;
1859		cc->write_tree = RB_ROOT;
1860		spin_unlock_irq(&cc->write_thread_lock);
1861
1862		BUG_ON(rb_parent(write_tree.rb_node));
1863
1864		/*
1865		 * Note: we cannot walk the tree here with rb_next because
1866		 * the structures may be freed when kcryptd_io_write is called.
1867		 */
1868		blk_start_plug(&plug);
1869		do {
1870			io = crypt_io_from_node(rb_first(&write_tree));
1871			rb_erase(&io->rb_node, &write_tree);
1872			kcryptd_io_write(io);
 
1873		} while (!RB_EMPTY_ROOT(&write_tree));
1874		blk_finish_plug(&plug);
1875	}
1876	return 0;
1877}
1878
1879static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async)
1880{
1881	struct bio *clone = io->ctx.bio_out;
1882	struct crypt_config *cc = io->cc;
1883	unsigned long flags;
1884	sector_t sector;
1885	struct rb_node **rbp, *parent;
1886
1887	if (unlikely(io->error)) {
1888		crypt_free_buffer_pages(cc, clone);
1889		bio_put(clone);
1890		crypt_dec_pending(io);
1891		return;
1892	}
1893
1894	/* crypt_convert should have filled the clone bio */
1895	BUG_ON(io->ctx.iter_out.bi_size);
1896
1897	clone->bi_iter.bi_sector = cc->start + io->sector;
1898
1899	if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) ||
1900	    test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) {
1901		submit_bio_noacct(clone);
1902		return;
1903	}
1904
1905	spin_lock_irqsave(&cc->write_thread_lock, flags);
1906	if (RB_EMPTY_ROOT(&cc->write_tree))
1907		wake_up_process(cc->write_thread);
1908	rbp = &cc->write_tree.rb_node;
1909	parent = NULL;
1910	sector = io->sector;
1911	while (*rbp) {
1912		parent = *rbp;
1913		if (sector < crypt_io_from_node(parent)->sector)
1914			rbp = &(*rbp)->rb_left;
1915		else
1916			rbp = &(*rbp)->rb_right;
1917	}
1918	rb_link_node(&io->rb_node, parent, rbp);
1919	rb_insert_color(&io->rb_node, &cc->write_tree);
1920	spin_unlock_irqrestore(&cc->write_thread_lock, flags);
1921}
1922
1923static bool kcryptd_crypt_write_inline(struct crypt_config *cc,
1924				       struct convert_context *ctx)
1925
1926{
1927	if (!test_bit(DM_CRYPT_WRITE_INLINE, &cc->flags))
1928		return false;
1929
1930	/*
1931	 * Note: zone append writes (REQ_OP_ZONE_APPEND) do not have ordering
1932	 * constraints so they do not need to be issued inline by
1933	 * kcryptd_crypt_write_convert().
1934	 */
1935	switch (bio_op(ctx->bio_in)) {
1936	case REQ_OP_WRITE:
1937	case REQ_OP_WRITE_SAME:
1938	case REQ_OP_WRITE_ZEROES:
1939		return true;
1940	default:
1941		return false;
1942	}
1943}
1944
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1945static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
1946{
1947	struct crypt_config *cc = io->cc;
1948	struct convert_context *ctx = &io->ctx;
1949	struct bio *clone;
1950	int crypt_finished;
1951	sector_t sector = io->sector;
1952	blk_status_t r;
1953
1954	/*
1955	 * Prevent io from disappearing until this function completes.
1956	 */
1957	crypt_inc_pending(io);
1958	crypt_convert_init(cc, ctx, NULL, io->base_bio, sector);
1959
1960	clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size);
1961	if (unlikely(!clone)) {
1962		io->error = BLK_STS_IOERR;
1963		goto dec;
1964	}
1965
1966	io->ctx.bio_out = clone;
1967	io->ctx.iter_out = clone->bi_iter;
1968
 
 
 
 
 
 
1969	sector += bio_sectors(clone);
1970
1971	crypt_inc_pending(io);
1972	r = crypt_convert(cc, ctx,
1973			  test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags));
 
 
 
 
 
 
 
 
 
 
1974	if (r)
1975		io->error = r;
1976	crypt_finished = atomic_dec_and_test(&ctx->cc_pending);
1977	if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) {
1978		/* Wait for completion signaled by kcryptd_async_done() */
1979		wait_for_completion(&ctx->restart);
1980		crypt_finished = 1;
1981	}
1982
1983	/* Encryption was already finished, submit io now */
1984	if (crypt_finished) {
1985		kcryptd_crypt_write_io_submit(io, 0);
1986		io->sector = sector;
1987	}
1988
1989dec:
1990	crypt_dec_pending(io);
1991}
1992
1993static void kcryptd_crypt_read_done(struct dm_crypt_io *io)
1994{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1995	crypt_dec_pending(io);
1996}
1997
1998static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
1999{
2000	struct crypt_config *cc = io->cc;
2001	blk_status_t r;
2002
2003	crypt_inc_pending(io);
2004
2005	crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio,
2006			   io->sector);
 
 
 
 
 
2007
2008	r = crypt_convert(cc, &io->ctx,
2009			  test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags));
 
 
 
 
 
 
 
 
 
 
2010	if (r)
2011		io->error = r;
2012
2013	if (atomic_dec_and_test(&io->ctx.cc_pending))
2014		kcryptd_crypt_read_done(io);
2015
2016	crypt_dec_pending(io);
2017}
2018
2019static void kcryptd_async_done(struct crypto_async_request *async_req,
2020			       int error)
2021{
2022	struct dm_crypt_request *dmreq = async_req->data;
2023	struct convert_context *ctx = dmreq->ctx;
2024	struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
2025	struct crypt_config *cc = io->cc;
2026
2027	/*
2028	 * A request from crypto driver backlog is going to be processed now,
2029	 * finish the completion and continue in crypt_convert().
2030	 * (Callback will be called for the second time for this request.)
2031	 */
2032	if (error == -EINPROGRESS) {
2033		complete(&ctx->restart);
2034		return;
2035	}
2036
2037	if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post)
2038		error = cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq);
2039
2040	if (error == -EBADMSG) {
2041		char b[BDEVNAME_SIZE];
2042		DMERR_LIMIT("%s: INTEGRITY AEAD ERROR, sector %llu", bio_devname(ctx->bio_in, b),
2043			    (unsigned long long)le64_to_cpu(*org_sector_of_dmreq(cc, dmreq)));
 
 
 
 
 
 
2044		io->error = BLK_STS_PROTECTION;
2045	} else if (error < 0)
2046		io->error = BLK_STS_IOERR;
2047
2048	crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio);
2049
2050	if (!atomic_dec_and_test(&ctx->cc_pending))
2051		return;
2052
2053	/*
2054	 * The request is fully completed: for inline writes, let
2055	 * kcryptd_crypt_write_convert() do the IO submission.
2056	 */
2057	if (bio_data_dir(io->base_bio) == READ) {
2058		kcryptd_crypt_read_done(io);
2059		return;
2060	}
2061
2062	if (kcryptd_crypt_write_inline(cc, ctx)) {
2063		complete(&ctx->restart);
2064		return;
2065	}
2066
2067	kcryptd_crypt_write_io_submit(io, 1);
2068}
2069
2070static void kcryptd_crypt(struct work_struct *work)
2071{
2072	struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
2073
2074	if (bio_data_dir(io->base_bio) == READ)
2075		kcryptd_crypt_read_convert(io);
2076	else
2077		kcryptd_crypt_write_convert(io);
2078}
2079
2080static void kcryptd_crypt_tasklet(unsigned long work)
2081{
2082	kcryptd_crypt((struct work_struct *)work);
2083}
2084
2085static void kcryptd_queue_crypt(struct dm_crypt_io *io)
2086{
2087	struct crypt_config *cc = io->cc;
2088
2089	if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) ||
2090	    (bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) {
2091		if (in_irq()) {
2092			/* Crypto API's "skcipher_walk_first() refuses to work in hard IRQ context */
2093			tasklet_init(&io->tasklet, kcryptd_crypt_tasklet, (unsigned long)&io->work);
2094			tasklet_schedule(&io->tasklet);
 
 
 
2095			return;
2096		}
2097
2098		kcryptd_crypt(&io->work);
2099		return;
2100	}
2101
2102	INIT_WORK(&io->work, kcryptd_crypt);
2103	queue_work(cc->crypt_queue, &io->work);
2104}
2105
2106static void crypt_free_tfms_aead(struct crypt_config *cc)
2107{
2108	if (!cc->cipher_tfm.tfms_aead)
2109		return;
2110
2111	if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) {
2112		crypto_free_aead(cc->cipher_tfm.tfms_aead[0]);
2113		cc->cipher_tfm.tfms_aead[0] = NULL;
2114	}
2115
2116	kfree(cc->cipher_tfm.tfms_aead);
2117	cc->cipher_tfm.tfms_aead = NULL;
2118}
2119
2120static void crypt_free_tfms_skcipher(struct crypt_config *cc)
2121{
2122	unsigned i;
2123
2124	if (!cc->cipher_tfm.tfms)
2125		return;
2126
2127	for (i = 0; i < cc->tfms_count; i++)
2128		if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) {
2129			crypto_free_skcipher(cc->cipher_tfm.tfms[i]);
2130			cc->cipher_tfm.tfms[i] = NULL;
2131		}
2132
2133	kfree(cc->cipher_tfm.tfms);
2134	cc->cipher_tfm.tfms = NULL;
2135}
2136
2137static void crypt_free_tfms(struct crypt_config *cc)
2138{
2139	if (crypt_integrity_aead(cc))
2140		crypt_free_tfms_aead(cc);
2141	else
2142		crypt_free_tfms_skcipher(cc);
2143}
2144
2145static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode)
2146{
2147	unsigned i;
2148	int err;
2149
2150	cc->cipher_tfm.tfms = kcalloc(cc->tfms_count,
2151				      sizeof(struct crypto_skcipher *),
2152				      GFP_KERNEL);
2153	if (!cc->cipher_tfm.tfms)
2154		return -ENOMEM;
2155
2156	for (i = 0; i < cc->tfms_count; i++) {
2157		cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0, 0);
 
2158		if (IS_ERR(cc->cipher_tfm.tfms[i])) {
2159			err = PTR_ERR(cc->cipher_tfm.tfms[i]);
2160			crypt_free_tfms(cc);
2161			return err;
2162		}
2163	}
2164
2165	/*
2166	 * dm-crypt performance can vary greatly depending on which crypto
2167	 * algorithm implementation is used.  Help people debug performance
2168	 * problems by logging the ->cra_driver_name.
2169	 */
2170	DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode,
2171	       crypto_skcipher_alg(any_tfm(cc))->base.cra_driver_name);
2172	return 0;
2173}
2174
2175static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode)
2176{
2177	int err;
2178
2179	cc->cipher_tfm.tfms = kmalloc(sizeof(struct crypto_aead *), GFP_KERNEL);
2180	if (!cc->cipher_tfm.tfms)
2181		return -ENOMEM;
2182
2183	cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0, 0);
 
2184	if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) {
2185		err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]);
2186		crypt_free_tfms(cc);
2187		return err;
2188	}
2189
2190	DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode,
2191	       crypto_aead_alg(any_tfm_aead(cc))->base.cra_driver_name);
2192	return 0;
2193}
2194
2195static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode)
2196{
2197	if (crypt_integrity_aead(cc))
2198		return crypt_alloc_tfms_aead(cc, ciphermode);
2199	else
2200		return crypt_alloc_tfms_skcipher(cc, ciphermode);
2201}
2202
2203static unsigned crypt_subkey_size(struct crypt_config *cc)
2204{
2205	return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count);
2206}
2207
2208static unsigned crypt_authenckey_size(struct crypt_config *cc)
2209{
2210	return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param));
2211}
2212
2213/*
2214 * If AEAD is composed like authenc(hmac(sha256),xts(aes)),
2215 * the key must be for some reason in special format.
2216 * This funcion converts cc->key to this special format.
2217 */
2218static void crypt_copy_authenckey(char *p, const void *key,
2219				  unsigned enckeylen, unsigned authkeylen)
2220{
2221	struct crypto_authenc_key_param *param;
2222	struct rtattr *rta;
2223
2224	rta = (struct rtattr *)p;
2225	param = RTA_DATA(rta);
2226	param->enckeylen = cpu_to_be32(enckeylen);
2227	rta->rta_len = RTA_LENGTH(sizeof(*param));
2228	rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM;
2229	p += RTA_SPACE(sizeof(*param));
2230	memcpy(p, key + enckeylen, authkeylen);
2231	p += authkeylen;
2232	memcpy(p, key, enckeylen);
2233}
2234
2235static int crypt_setkey(struct crypt_config *cc)
2236{
2237	unsigned subkey_size;
2238	int err = 0, i, r;
2239
2240	/* Ignore extra keys (which are used for IV etc) */
2241	subkey_size = crypt_subkey_size(cc);
2242
2243	if (crypt_integrity_hmac(cc)) {
2244		if (subkey_size < cc->key_mac_size)
2245			return -EINVAL;
2246
2247		crypt_copy_authenckey(cc->authenc_key, cc->key,
2248				      subkey_size - cc->key_mac_size,
2249				      cc->key_mac_size);
2250	}
2251
2252	for (i = 0; i < cc->tfms_count; i++) {
2253		if (crypt_integrity_hmac(cc))
2254			r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i],
2255				cc->authenc_key, crypt_authenckey_size(cc));
2256		else if (crypt_integrity_aead(cc))
2257			r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i],
2258					       cc->key + (i * subkey_size),
2259					       subkey_size);
2260		else
2261			r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i],
2262						   cc->key + (i * subkey_size),
2263						   subkey_size);
2264		if (r)
2265			err = r;
2266	}
2267
2268	if (crypt_integrity_hmac(cc))
2269		memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc));
2270
2271	return err;
2272}
2273
2274#ifdef CONFIG_KEYS
2275
2276static bool contains_whitespace(const char *str)
2277{
2278	while (*str)
2279		if (isspace(*str++))
2280			return true;
2281	return false;
2282}
2283
2284static int set_key_user(struct crypt_config *cc, struct key *key)
2285{
2286	const struct user_key_payload *ukp;
2287
2288	ukp = user_key_payload_locked(key);
2289	if (!ukp)
2290		return -EKEYREVOKED;
2291
2292	if (cc->key_size != ukp->datalen)
2293		return -EINVAL;
2294
2295	memcpy(cc->key, ukp->data, cc->key_size);
2296
2297	return 0;
2298}
2299
2300#if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE)
2301static int set_key_encrypted(struct crypt_config *cc, struct key *key)
2302{
2303	const struct encrypted_key_payload *ekp;
2304
2305	ekp = key->payload.data[0];
2306	if (!ekp)
2307		return -EKEYREVOKED;
2308
2309	if (cc->key_size != ekp->decrypted_datalen)
2310		return -EINVAL;
2311
2312	memcpy(cc->key, ekp->decrypted_data, cc->key_size);
2313
2314	return 0;
2315}
2316#endif /* CONFIG_ENCRYPTED_KEYS */
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
2317
2318static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string)
2319{
2320	char *new_key_string, *key_desc;
2321	int ret;
2322	struct key_type *type;
2323	struct key *key;
2324	int (*set_key)(struct crypt_config *cc, struct key *key);
2325
2326	/*
2327	 * Reject key_string with whitespace. dm core currently lacks code for
2328	 * proper whitespace escaping in arguments on DM_TABLE_STATUS path.
2329	 */
2330	if (contains_whitespace(key_string)) {
2331		DMERR("whitespace chars not allowed in key string");
2332		return -EINVAL;
2333	}
2334
2335	/* look for next ':' separating key_type from key_description */
2336	key_desc = strpbrk(key_string, ":");
2337	if (!key_desc || key_desc == key_string || !strlen(key_desc + 1))
2338		return -EINVAL;
2339
2340	if (!strncmp(key_string, "logon:", key_desc - key_string + 1)) {
2341		type = &key_type_logon;
2342		set_key = set_key_user;
2343	} else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) {
2344		type = &key_type_user;
2345		set_key = set_key_user;
2346#if defined(CONFIG_ENCRYPTED_KEYS) || defined(CONFIG_ENCRYPTED_KEYS_MODULE)
2347	} else if (!strncmp(key_string, "encrypted:", key_desc - key_string + 1)) {
2348		type = &key_type_encrypted;
2349		set_key = set_key_encrypted;
2350#endif
 
 
 
2351	} else {
2352		return -EINVAL;
2353	}
2354
2355	new_key_string = kstrdup(key_string, GFP_KERNEL);
2356	if (!new_key_string)
2357		return -ENOMEM;
2358
2359	key = request_key(type, key_desc + 1, NULL);
2360	if (IS_ERR(key)) {
2361		kfree_sensitive(new_key_string);
2362		return PTR_ERR(key);
2363	}
2364
2365	down_read(&key->sem);
2366
2367	ret = set_key(cc, key);
2368	if (ret < 0) {
2369		up_read(&key->sem);
2370		key_put(key);
2371		kfree_sensitive(new_key_string);
2372		return ret;
2373	}
2374
2375	up_read(&key->sem);
2376	key_put(key);
2377
2378	/* clear the flag since following operations may invalidate previously valid key */
2379	clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2380
2381	ret = crypt_setkey(cc);
2382
2383	if (!ret) {
2384		set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2385		kfree_sensitive(cc->key_string);
2386		cc->key_string = new_key_string;
2387	} else
2388		kfree_sensitive(new_key_string);
2389
2390	return ret;
2391}
2392
2393static int get_key_size(char **key_string)
2394{
2395	char *colon, dummy;
2396	int ret;
2397
2398	if (*key_string[0] != ':')
2399		return strlen(*key_string) >> 1;
2400
2401	/* look for next ':' in key string */
2402	colon = strpbrk(*key_string + 1, ":");
2403	if (!colon)
2404		return -EINVAL;
2405
2406	if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':')
2407		return -EINVAL;
2408
2409	*key_string = colon;
2410
2411	/* remaining key string should be :<logon|user>:<key_desc> */
2412
2413	return ret;
2414}
2415
2416#else
2417
2418static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string)
2419{
2420	return -EINVAL;
2421}
2422
2423static int get_key_size(char **key_string)
2424{
2425	return (*key_string[0] == ':') ? -EINVAL : strlen(*key_string) >> 1;
2426}
2427
2428#endif /* CONFIG_KEYS */
2429
2430static int crypt_set_key(struct crypt_config *cc, char *key)
2431{
2432	int r = -EINVAL;
2433	int key_string_len = strlen(key);
2434
2435	/* Hyphen (which gives a key_size of zero) means there is no key. */
2436	if (!cc->key_size && strcmp(key, "-"))
2437		goto out;
2438
2439	/* ':' means the key is in kernel keyring, short-circuit normal key processing */
2440	if (key[0] == ':') {
2441		r = crypt_set_keyring_key(cc, key + 1);
2442		goto out;
2443	}
2444
2445	/* clear the flag since following operations may invalidate previously valid key */
2446	clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2447
2448	/* wipe references to any kernel keyring key */
2449	kfree_sensitive(cc->key_string);
2450	cc->key_string = NULL;
2451
2452	/* Decode key from its hex representation. */
2453	if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0)
2454		goto out;
2455
2456	r = crypt_setkey(cc);
2457	if (!r)
2458		set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2459
2460out:
2461	/* Hex key string not needed after here, so wipe it. */
2462	memset(key, '0', key_string_len);
2463
2464	return r;
2465}
2466
2467static int crypt_wipe_key(struct crypt_config *cc)
2468{
2469	int r;
2470
2471	clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2472	get_random_bytes(&cc->key, cc->key_size);
2473
2474	/* Wipe IV private keys */
2475	if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) {
2476		r = cc->iv_gen_ops->wipe(cc);
2477		if (r)
2478			return r;
2479	}
2480
2481	kfree_sensitive(cc->key_string);
2482	cc->key_string = NULL;
2483	r = crypt_setkey(cc);
2484	memset(&cc->key, 0, cc->key_size * sizeof(u8));
2485
2486	return r;
2487}
2488
2489static void crypt_calculate_pages_per_client(void)
2490{
2491	unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100;
2492
2493	if (!dm_crypt_clients_n)
2494		return;
2495
2496	pages /= dm_crypt_clients_n;
2497	if (pages < DM_CRYPT_MIN_PAGES_PER_CLIENT)
2498		pages = DM_CRYPT_MIN_PAGES_PER_CLIENT;
2499	dm_crypt_pages_per_client = pages;
2500}
2501
2502static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data)
2503{
2504	struct crypt_config *cc = pool_data;
2505	struct page *page;
2506
2507	if (unlikely(percpu_counter_compare(&cc->n_allocated_pages, dm_crypt_pages_per_client) >= 0) &&
 
 
 
 
 
2508	    likely(gfp_mask & __GFP_NORETRY))
2509		return NULL;
2510
2511	page = alloc_page(gfp_mask);
2512	if (likely(page != NULL))
2513		percpu_counter_add(&cc->n_allocated_pages, 1);
2514
2515	return page;
2516}
2517
2518static void crypt_page_free(void *page, void *pool_data)
2519{
2520	struct crypt_config *cc = pool_data;
2521
2522	__free_page(page);
2523	percpu_counter_sub(&cc->n_allocated_pages, 1);
2524}
2525
2526static void crypt_dtr(struct dm_target *ti)
2527{
2528	struct crypt_config *cc = ti->private;
2529
2530	ti->private = NULL;
2531
2532	if (!cc)
2533		return;
2534
2535	if (cc->write_thread)
2536		kthread_stop(cc->write_thread);
2537
2538	if (cc->io_queue)
2539		destroy_workqueue(cc->io_queue);
2540	if (cc->crypt_queue)
2541		destroy_workqueue(cc->crypt_queue);
2542
2543	crypt_free_tfms(cc);
2544
2545	bioset_exit(&cc->bs);
2546
2547	mempool_exit(&cc->page_pool);
2548	mempool_exit(&cc->req_pool);
2549	mempool_exit(&cc->tag_pool);
2550
2551	WARN_ON(percpu_counter_sum(&cc->n_allocated_pages) != 0);
2552	percpu_counter_destroy(&cc->n_allocated_pages);
2553
2554	if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
2555		cc->iv_gen_ops->dtr(cc);
2556
2557	if (cc->dev)
2558		dm_put_device(ti, cc->dev);
2559
2560	kfree_sensitive(cc->cipher_string);
2561	kfree_sensitive(cc->key_string);
2562	kfree_sensitive(cc->cipher_auth);
2563	kfree_sensitive(cc->authenc_key);
2564
2565	mutex_destroy(&cc->bio_alloc_lock);
2566
2567	/* Must zero key material before freeing */
2568	kfree_sensitive(cc);
2569
2570	spin_lock(&dm_crypt_clients_lock);
2571	WARN_ON(!dm_crypt_clients_n);
2572	dm_crypt_clients_n--;
2573	crypt_calculate_pages_per_client();
2574	spin_unlock(&dm_crypt_clients_lock);
 
 
2575}
2576
2577static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode)
2578{
2579	struct crypt_config *cc = ti->private;
2580
2581	if (crypt_integrity_aead(cc))
2582		cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc));
2583	else
2584		cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));
2585
2586	if (cc->iv_size)
2587		/* at least a 64 bit sector number should fit in our buffer */
2588		cc->iv_size = max(cc->iv_size,
2589				  (unsigned int)(sizeof(u64) / sizeof(u8)));
2590	else if (ivmode) {
2591		DMWARN("Selected cipher does not support IVs");
2592		ivmode = NULL;
2593	}
2594
2595	/* Choose ivmode, see comments at iv code. */
2596	if (ivmode == NULL)
2597		cc->iv_gen_ops = NULL;
2598	else if (strcmp(ivmode, "plain") == 0)
2599		cc->iv_gen_ops = &crypt_iv_plain_ops;
2600	else if (strcmp(ivmode, "plain64") == 0)
2601		cc->iv_gen_ops = &crypt_iv_plain64_ops;
2602	else if (strcmp(ivmode, "plain64be") == 0)
2603		cc->iv_gen_ops = &crypt_iv_plain64be_ops;
2604	else if (strcmp(ivmode, "essiv") == 0)
2605		cc->iv_gen_ops = &crypt_iv_essiv_ops;
2606	else if (strcmp(ivmode, "benbi") == 0)
2607		cc->iv_gen_ops = &crypt_iv_benbi_ops;
2608	else if (strcmp(ivmode, "null") == 0)
2609		cc->iv_gen_ops = &crypt_iv_null_ops;
2610	else if (strcmp(ivmode, "eboiv") == 0)
2611		cc->iv_gen_ops = &crypt_iv_eboiv_ops;
2612	else if (strcmp(ivmode, "elephant") == 0) {
2613		cc->iv_gen_ops = &crypt_iv_elephant_ops;
2614		cc->key_parts = 2;
2615		cc->key_extra_size = cc->key_size / 2;
2616		if (cc->key_extra_size > ELEPHANT_MAX_KEY_SIZE)
2617			return -EINVAL;
2618		set_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags);
2619	} else if (strcmp(ivmode, "lmk") == 0) {
2620		cc->iv_gen_ops = &crypt_iv_lmk_ops;
2621		/*
2622		 * Version 2 and 3 is recognised according
2623		 * to length of provided multi-key string.
2624		 * If present (version 3), last key is used as IV seed.
2625		 * All keys (including IV seed) are always the same size.
2626		 */
2627		if (cc->key_size % cc->key_parts) {
2628			cc->key_parts++;
2629			cc->key_extra_size = cc->key_size / cc->key_parts;
2630		}
2631	} else if (strcmp(ivmode, "tcw") == 0) {
2632		cc->iv_gen_ops = &crypt_iv_tcw_ops;
2633		cc->key_parts += 2; /* IV + whitening */
2634		cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE;
2635	} else if (strcmp(ivmode, "random") == 0) {
2636		cc->iv_gen_ops = &crypt_iv_random_ops;
2637		/* Need storage space in integrity fields. */
2638		cc->integrity_iv_size = cc->iv_size;
2639	} else {
2640		ti->error = "Invalid IV mode";
2641		return -EINVAL;
2642	}
2643
2644	return 0;
2645}
2646
2647/*
2648 * Workaround to parse HMAC algorithm from AEAD crypto API spec.
2649 * The HMAC is needed to calculate tag size (HMAC digest size).
2650 * This should be probably done by crypto-api calls (once available...)
2651 */
2652static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api)
2653{
2654	char *start, *end, *mac_alg = NULL;
2655	struct crypto_ahash *mac;
2656
2657	if (!strstarts(cipher_api, "authenc("))
2658		return 0;
2659
2660	start = strchr(cipher_api, '(');
2661	end = strchr(cipher_api, ',');
2662	if (!start || !end || ++start > end)
2663		return -EINVAL;
2664
2665	mac_alg = kzalloc(end - start + 1, GFP_KERNEL);
2666	if (!mac_alg)
2667		return -ENOMEM;
2668	strncpy(mac_alg, start, end - start);
2669
2670	mac = crypto_alloc_ahash(mac_alg, 0, 0);
2671	kfree(mac_alg);
2672
2673	if (IS_ERR(mac))
2674		return PTR_ERR(mac);
2675
2676	cc->key_mac_size = crypto_ahash_digestsize(mac);
2677	crypto_free_ahash(mac);
2678
2679	cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL);
2680	if (!cc->authenc_key)
2681		return -ENOMEM;
2682
2683	return 0;
2684}
2685
2686static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key,
2687				char **ivmode, char **ivopts)
2688{
2689	struct crypt_config *cc = ti->private;
2690	char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME];
2691	int ret = -EINVAL;
2692
2693	cc->tfms_count = 1;
2694
2695	/*
2696	 * New format (capi: prefix)
2697	 * capi:cipher_api_spec-iv:ivopts
2698	 */
2699	tmp = &cipher_in[strlen("capi:")];
2700
2701	/* Separate IV options if present, it can contain another '-' in hash name */
2702	*ivopts = strrchr(tmp, ':');
2703	if (*ivopts) {
2704		**ivopts = '\0';
2705		(*ivopts)++;
2706	}
2707	/* Parse IV mode */
2708	*ivmode = strrchr(tmp, '-');
2709	if (*ivmode) {
2710		**ivmode = '\0';
2711		(*ivmode)++;
2712	}
2713	/* The rest is crypto API spec */
2714	cipher_api = tmp;
2715
2716	/* Alloc AEAD, can be used only in new format. */
2717	if (crypt_integrity_aead(cc)) {
2718		ret = crypt_ctr_auth_cipher(cc, cipher_api);
2719		if (ret < 0) {
2720			ti->error = "Invalid AEAD cipher spec";
2721			return -ENOMEM;
2722		}
2723	}
2724
2725	if (*ivmode && !strcmp(*ivmode, "lmk"))
2726		cc->tfms_count = 64;
2727
2728	if (*ivmode && !strcmp(*ivmode, "essiv")) {
2729		if (!*ivopts) {
2730			ti->error = "Digest algorithm missing for ESSIV mode";
2731			return -EINVAL;
2732		}
2733		ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)",
2734			       cipher_api, *ivopts);
2735		if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) {
2736			ti->error = "Cannot allocate cipher string";
2737			return -ENOMEM;
2738		}
2739		cipher_api = buf;
2740	}
2741
2742	cc->key_parts = cc->tfms_count;
2743
2744	/* Allocate cipher */
2745	ret = crypt_alloc_tfms(cc, cipher_api);
2746	if (ret < 0) {
2747		ti->error = "Error allocating crypto tfm";
2748		return ret;
2749	}
2750
2751	if (crypt_integrity_aead(cc))
2752		cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc));
2753	else
2754		cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));
2755
2756	return 0;
2757}
2758
2759static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key,
2760				char **ivmode, char **ivopts)
2761{
2762	struct crypt_config *cc = ti->private;
2763	char *tmp, *cipher, *chainmode, *keycount;
2764	char *cipher_api = NULL;
2765	int ret = -EINVAL;
2766	char dummy;
2767
2768	if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) {
2769		ti->error = "Bad cipher specification";
2770		return -EINVAL;
2771	}
2772
2773	/*
2774	 * Legacy dm-crypt cipher specification
2775	 * cipher[:keycount]-mode-iv:ivopts
2776	 */
2777	tmp = cipher_in;
2778	keycount = strsep(&tmp, "-");
2779	cipher = strsep(&keycount, ":");
2780
2781	if (!keycount)
2782		cc->tfms_count = 1;
2783	else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 ||
2784		 !is_power_of_2(cc->tfms_count)) {
2785		ti->error = "Bad cipher key count specification";
2786		return -EINVAL;
2787	}
2788	cc->key_parts = cc->tfms_count;
2789
2790	chainmode = strsep(&tmp, "-");
2791	*ivmode = strsep(&tmp, ":");
2792	*ivopts = tmp;
2793
2794	/*
2795	 * For compatibility with the original dm-crypt mapping format, if
2796	 * only the cipher name is supplied, use cbc-plain.
2797	 */
2798	if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) {
2799		chainmode = "cbc";
2800		*ivmode = "plain";
2801	}
2802
2803	if (strcmp(chainmode, "ecb") && !*ivmode) {
2804		ti->error = "IV mechanism required";
2805		return -EINVAL;
2806	}
2807
2808	cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
2809	if (!cipher_api)
2810		goto bad_mem;
2811
2812	if (*ivmode && !strcmp(*ivmode, "essiv")) {
2813		if (!*ivopts) {
2814			ti->error = "Digest algorithm missing for ESSIV mode";
2815			kfree(cipher_api);
2816			return -EINVAL;
2817		}
2818		ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
2819			       "essiv(%s(%s),%s)", chainmode, cipher, *ivopts);
2820	} else {
2821		ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
2822			       "%s(%s)", chainmode, cipher);
2823	}
2824	if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) {
2825		kfree(cipher_api);
2826		goto bad_mem;
2827	}
2828
2829	/* Allocate cipher */
2830	ret = crypt_alloc_tfms(cc, cipher_api);
2831	if (ret < 0) {
2832		ti->error = "Error allocating crypto tfm";
2833		kfree(cipher_api);
2834		return ret;
2835	}
2836	kfree(cipher_api);
2837
2838	return 0;
2839bad_mem:
2840	ti->error = "Cannot allocate cipher strings";
2841	return -ENOMEM;
2842}
2843
2844static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key)
2845{
2846	struct crypt_config *cc = ti->private;
2847	char *ivmode = NULL, *ivopts = NULL;
2848	int ret;
2849
2850	cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL);
2851	if (!cc->cipher_string) {
2852		ti->error = "Cannot allocate cipher strings";
2853		return -ENOMEM;
2854	}
2855
2856	if (strstarts(cipher_in, "capi:"))
2857		ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts);
2858	else
2859		ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts);
2860	if (ret)
2861		return ret;
2862
2863	/* Initialize IV */
2864	ret = crypt_ctr_ivmode(ti, ivmode);
2865	if (ret < 0)
2866		return ret;
2867
2868	/* Initialize and set key */
2869	ret = crypt_set_key(cc, key);
2870	if (ret < 0) {
2871		ti->error = "Error decoding and setting key";
2872		return ret;
2873	}
2874
2875	/* Allocate IV */
2876	if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) {
2877		ret = cc->iv_gen_ops->ctr(cc, ti, ivopts);
2878		if (ret < 0) {
2879			ti->error = "Error creating IV";
2880			return ret;
2881		}
2882	}
2883
2884	/* Initialize IV (set keys for ESSIV etc) */
2885	if (cc->iv_gen_ops && cc->iv_gen_ops->init) {
2886		ret = cc->iv_gen_ops->init(cc);
2887		if (ret < 0) {
2888			ti->error = "Error initialising IV";
2889			return ret;
2890		}
2891	}
2892
2893	/* wipe the kernel key payload copy */
2894	if (cc->key_string)
2895		memset(cc->key, 0, cc->key_size * sizeof(u8));
2896
2897	return ret;
2898}
2899
2900static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv)
2901{
2902	struct crypt_config *cc = ti->private;
2903	struct dm_arg_set as;
2904	static const struct dm_arg _args[] = {
2905		{0, 8, "Invalid number of feature args"},
2906	};
2907	unsigned int opt_params, val;
2908	const char *opt_string, *sval;
2909	char dummy;
2910	int ret;
2911
2912	/* Optional parameters */
2913	as.argc = argc;
2914	as.argv = argv;
2915
2916	ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error);
2917	if (ret)
2918		return ret;
2919
2920	while (opt_params--) {
2921		opt_string = dm_shift_arg(&as);
2922		if (!opt_string) {
2923			ti->error = "Not enough feature arguments";
2924			return -EINVAL;
2925		}
2926
2927		if (!strcasecmp(opt_string, "allow_discards"))
2928			ti->num_discard_bios = 1;
2929
2930		else if (!strcasecmp(opt_string, "same_cpu_crypt"))
2931			set_bit(DM_CRYPT_SAME_CPU, &cc->flags);
2932
2933		else if (!strcasecmp(opt_string, "submit_from_crypt_cpus"))
2934			set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags);
2935		else if (!strcasecmp(opt_string, "no_read_workqueue"))
2936			set_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags);
2937		else if (!strcasecmp(opt_string, "no_write_workqueue"))
2938			set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
2939		else if (sscanf(opt_string, "integrity:%u:", &val) == 1) {
2940			if (val == 0 || val > MAX_TAG_SIZE) {
2941				ti->error = "Invalid integrity arguments";
2942				return -EINVAL;
2943			}
2944			cc->on_disk_tag_size = val;
2945			sval = strchr(opt_string + strlen("integrity:"), ':') + 1;
2946			if (!strcasecmp(sval, "aead")) {
2947				set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags);
2948			} else  if (strcasecmp(sval, "none")) {
2949				ti->error = "Unknown integrity profile";
2950				return -EINVAL;
2951			}
2952
2953			cc->cipher_auth = kstrdup(sval, GFP_KERNEL);
2954			if (!cc->cipher_auth)
2955				return -ENOMEM;
2956		} else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) {
2957			if (cc->sector_size < (1 << SECTOR_SHIFT) ||
2958			    cc->sector_size > 4096 ||
2959			    (cc->sector_size & (cc->sector_size - 1))) {
2960				ti->error = "Invalid feature value for sector_size";
2961				return -EINVAL;
2962			}
2963			if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) {
2964				ti->error = "Device size is not multiple of sector_size feature";
2965				return -EINVAL;
2966			}
2967			cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT;
2968		} else if (!strcasecmp(opt_string, "iv_large_sectors"))
2969			set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags);
2970		else {
2971			ti->error = "Invalid feature arguments";
2972			return -EINVAL;
2973		}
2974	}
2975
2976	return 0;
2977}
2978
2979#ifdef CONFIG_BLK_DEV_ZONED
2980
2981static int crypt_report_zones(struct dm_target *ti,
2982		struct dm_report_zones_args *args, unsigned int nr_zones)
2983{
2984	struct crypt_config *cc = ti->private;
2985	sector_t sector = cc->start + dm_target_offset(ti, args->next_sector);
2986
2987	args->start = cc->start;
2988	return blkdev_report_zones(cc->dev->bdev, sector, nr_zones,
2989				   dm_report_zones_cb, args);
2990}
2991
 
2992#endif
2993
2994/*
2995 * Construct an encryption mapping:
2996 * <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start>
2997 */
2998static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
2999{
3000	struct crypt_config *cc;
3001	const char *devname = dm_table_device_name(ti->table);
3002	int key_size;
3003	unsigned int align_mask;
3004	unsigned long long tmpll;
3005	int ret;
3006	size_t iv_size_padding, additional_req_size;
3007	char dummy;
3008
3009	if (argc < 5) {
3010		ti->error = "Not enough arguments";
3011		return -EINVAL;
3012	}
3013
3014	key_size = get_key_size(&argv[1]);
3015	if (key_size < 0) {
3016		ti->error = "Cannot parse key size";
3017		return -EINVAL;
3018	}
3019
3020	cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL);
3021	if (!cc) {
3022		ti->error = "Cannot allocate encryption context";
3023		return -ENOMEM;
3024	}
3025	cc->key_size = key_size;
3026	cc->sector_size = (1 << SECTOR_SHIFT);
3027	cc->sector_shift = 0;
3028
3029	ti->private = cc;
3030
3031	spin_lock(&dm_crypt_clients_lock);
3032	dm_crypt_clients_n++;
3033	crypt_calculate_pages_per_client();
3034	spin_unlock(&dm_crypt_clients_lock);
3035
3036	ret = percpu_counter_init(&cc->n_allocated_pages, 0, GFP_KERNEL);
3037	if (ret < 0)
3038		goto bad;
3039
3040	/* Optional parameters need to be read before cipher constructor */
3041	if (argc > 5) {
3042		ret = crypt_ctr_optional(ti, argc - 5, &argv[5]);
3043		if (ret)
3044			goto bad;
3045	}
3046
3047	ret = crypt_ctr_cipher(ti, argv[0], argv[1]);
3048	if (ret < 0)
3049		goto bad;
3050
3051	if (crypt_integrity_aead(cc)) {
3052		cc->dmreq_start = sizeof(struct aead_request);
3053		cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc));
3054		align_mask = crypto_aead_alignmask(any_tfm_aead(cc));
3055	} else {
3056		cc->dmreq_start = sizeof(struct skcipher_request);
3057		cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc));
3058		align_mask = crypto_skcipher_alignmask(any_tfm(cc));
3059	}
3060	cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request));
3061
3062	if (align_mask < CRYPTO_MINALIGN) {
3063		/* Allocate the padding exactly */
3064		iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request))
3065				& align_mask;
3066	} else {
3067		/*
3068		 * If the cipher requires greater alignment than kmalloc
3069		 * alignment, we don't know the exact position of the
3070		 * initialization vector. We must assume worst case.
3071		 */
3072		iv_size_padding = align_mask;
3073	}
3074
3075	/*  ...| IV + padding | original IV | original sec. number | bio tag offset | */
3076	additional_req_size = sizeof(struct dm_crypt_request) +
3077		iv_size_padding + cc->iv_size +
3078		cc->iv_size +
3079		sizeof(uint64_t) +
3080		sizeof(unsigned int);
3081
3082	ret = mempool_init_kmalloc_pool(&cc->req_pool, MIN_IOS, cc->dmreq_start + additional_req_size);
3083	if (ret) {
3084		ti->error = "Cannot allocate crypt request mempool";
3085		goto bad;
3086	}
3087
3088	cc->per_bio_data_size = ti->per_io_data_size =
3089		ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size,
3090		      ARCH_KMALLOC_MINALIGN);
3091
3092	ret = mempool_init(&cc->page_pool, BIO_MAX_PAGES, crypt_page_alloc, crypt_page_free, cc);
3093	if (ret) {
3094		ti->error = "Cannot allocate page mempool";
3095		goto bad;
3096	}
3097
3098	ret = bioset_init(&cc->bs, MIN_IOS, 0, BIOSET_NEED_BVECS);
3099	if (ret) {
3100		ti->error = "Cannot allocate crypt bioset";
3101		goto bad;
3102	}
3103
3104	mutex_init(&cc->bio_alloc_lock);
3105
3106	ret = -EINVAL;
3107	if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) ||
3108	    (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) {
3109		ti->error = "Invalid iv_offset sector";
3110		goto bad;
3111	}
3112	cc->iv_offset = tmpll;
3113
3114	ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev);
3115	if (ret) {
3116		ti->error = "Device lookup failed";
3117		goto bad;
3118	}
3119
3120	ret = -EINVAL;
3121	if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) {
3122		ti->error = "Invalid device sector";
3123		goto bad;
3124	}
3125	cc->start = tmpll;
3126
3127	/*
3128	 * For zoned block devices, we need to preserve the issuer write
3129	 * ordering. To do so, disable write workqueues and force inline
3130	 * encryption completion.
3131	 */
3132	if (bdev_is_zoned(cc->dev->bdev)) {
 
 
 
 
 
3133		set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
3134		set_bit(DM_CRYPT_WRITE_INLINE, &cc->flags);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3135	}
3136
3137	if (crypt_integrity_aead(cc) || cc->integrity_iv_size) {
3138		ret = crypt_integrity_ctr(cc, ti);
3139		if (ret)
3140			goto bad;
3141
3142		cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->on_disk_tag_size;
3143		if (!cc->tag_pool_max_sectors)
3144			cc->tag_pool_max_sectors = 1;
3145
3146		ret = mempool_init_kmalloc_pool(&cc->tag_pool, MIN_IOS,
3147			cc->tag_pool_max_sectors * cc->on_disk_tag_size);
3148		if (ret) {
3149			ti->error = "Cannot allocate integrity tags mempool";
3150			goto bad;
3151		}
3152
3153		cc->tag_pool_max_sectors <<= cc->sector_shift;
3154	}
3155
3156	ret = -ENOMEM;
3157	cc->io_queue = alloc_workqueue("kcryptd_io/%s", WQ_MEM_RECLAIM, 1, devname);
3158	if (!cc->io_queue) {
3159		ti->error = "Couldn't create kcryptd io queue";
3160		goto bad;
3161	}
3162
3163	if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
3164		cc->crypt_queue = alloc_workqueue("kcryptd/%s", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM,
3165						  1, devname);
3166	else
3167		cc->crypt_queue = alloc_workqueue("kcryptd/%s",
3168						  WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND,
3169						  num_online_cpus(), devname);
3170	if (!cc->crypt_queue) {
3171		ti->error = "Couldn't create kcryptd queue";
3172		goto bad;
3173	}
3174
3175	spin_lock_init(&cc->write_thread_lock);
3176	cc->write_tree = RB_ROOT;
3177
3178	cc->write_thread = kthread_create(dmcrypt_write, cc, "dmcrypt_write/%s", devname);
3179	if (IS_ERR(cc->write_thread)) {
3180		ret = PTR_ERR(cc->write_thread);
3181		cc->write_thread = NULL;
3182		ti->error = "Couldn't spawn write thread";
3183		goto bad;
3184	}
3185	wake_up_process(cc->write_thread);
3186
3187	ti->num_flush_bios = 1;
 
 
3188
 
3189	return 0;
3190
3191bad:
 
3192	crypt_dtr(ti);
3193	return ret;
3194}
3195
3196static int crypt_map(struct dm_target *ti, struct bio *bio)
3197{
3198	struct dm_crypt_io *io;
3199	struct crypt_config *cc = ti->private;
3200
3201	/*
3202	 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues.
3203	 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight
3204	 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters
3205	 */
3206	if (unlikely(bio->bi_opf & REQ_PREFLUSH ||
3207	    bio_op(bio) == REQ_OP_DISCARD)) {
3208		bio_set_dev(bio, cc->dev->bdev);
3209		if (bio_sectors(bio))
3210			bio->bi_iter.bi_sector = cc->start +
3211				dm_target_offset(ti, bio->bi_iter.bi_sector);
3212		return DM_MAPIO_REMAPPED;
3213	}
3214
3215	/*
3216	 * Check if bio is too large, split as needed.
3217	 */
3218	if (unlikely(bio->bi_iter.bi_size > (BIO_MAX_PAGES << PAGE_SHIFT)) &&
3219	    (bio_data_dir(bio) == WRITE || cc->on_disk_tag_size))
3220		dm_accept_partial_bio(bio, ((BIO_MAX_PAGES << PAGE_SHIFT) >> SECTOR_SHIFT));
3221
3222	/*
3223	 * Ensure that bio is a multiple of internal sector encryption size
3224	 * and is aligned to this size as defined in IO hints.
3225	 */
3226	if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0))
3227		return DM_MAPIO_KILL;
3228
3229	if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1)))
3230		return DM_MAPIO_KILL;
3231
3232	io = dm_per_bio_data(bio, cc->per_bio_data_size);
3233	crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector));
3234
3235	if (cc->on_disk_tag_size) {
3236		unsigned tag_len = cc->on_disk_tag_size * (bio_sectors(bio) >> cc->sector_shift);
3237
3238		if (unlikely(tag_len > KMALLOC_MAX_SIZE) ||
3239		    unlikely(!(io->integrity_metadata = kmalloc(tag_len,
3240				GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN)))) {
 
 
 
3241			if (bio_sectors(bio) > cc->tag_pool_max_sectors)
3242				dm_accept_partial_bio(bio, cc->tag_pool_max_sectors);
3243			io->integrity_metadata = mempool_alloc(&cc->tag_pool, GFP_NOIO);
3244			io->integrity_metadata_from_pool = true;
3245		}
3246	}
3247
3248	if (crypt_integrity_aead(cc))
3249		io->ctx.r.req_aead = (struct aead_request *)(io + 1);
3250	else
3251		io->ctx.r.req = (struct skcipher_request *)(io + 1);
3252
3253	if (bio_data_dir(io->base_bio) == READ) {
3254		if (kcryptd_io_read(io, GFP_NOWAIT))
3255			kcryptd_queue_read(io);
3256	} else
3257		kcryptd_queue_crypt(io);
3258
3259	return DM_MAPIO_SUBMITTED;
3260}
3261
 
 
 
 
 
3262static void crypt_status(struct dm_target *ti, status_type_t type,
3263			 unsigned status_flags, char *result, unsigned maxlen)
3264{
3265	struct crypt_config *cc = ti->private;
3266	unsigned i, sz = 0;
3267	int num_feature_args = 0;
3268
3269	switch (type) {
3270	case STATUSTYPE_INFO:
3271		result[0] = '\0';
3272		break;
3273
3274	case STATUSTYPE_TABLE:
3275		DMEMIT("%s ", cc->cipher_string);
3276
3277		if (cc->key_size > 0) {
3278			if (cc->key_string)
3279				DMEMIT(":%u:%s", cc->key_size, cc->key_string);
3280			else
3281				for (i = 0; i < cc->key_size; i++)
3282					DMEMIT("%02x", cc->key[i]);
 
 
 
3283		} else
3284			DMEMIT("-");
3285
3286		DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset,
3287				cc->dev->name, (unsigned long long)cc->start);
3288
3289		num_feature_args += !!ti->num_discard_bios;
3290		num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags);
3291		num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags);
3292		num_feature_args += test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags);
3293		num_feature_args += test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
3294		num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT);
3295		num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags);
3296		if (cc->on_disk_tag_size)
3297			num_feature_args++;
3298		if (num_feature_args) {
3299			DMEMIT(" %d", num_feature_args);
3300			if (ti->num_discard_bios)
3301				DMEMIT(" allow_discards");
3302			if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
3303				DMEMIT(" same_cpu_crypt");
3304			if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags))
3305				DMEMIT(" submit_from_crypt_cpus");
3306			if (test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags))
3307				DMEMIT(" no_read_workqueue");
3308			if (test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))
3309				DMEMIT(" no_write_workqueue");
3310			if (cc->on_disk_tag_size)
3311				DMEMIT(" integrity:%u:%s", cc->on_disk_tag_size, cc->cipher_auth);
3312			if (cc->sector_size != (1 << SECTOR_SHIFT))
3313				DMEMIT(" sector_size:%d", cc->sector_size);
3314			if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
3315				DMEMIT(" iv_large_sectors");
3316		}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3317
 
 
 
 
 
 
 
 
 
 
 
 
 
3318		break;
3319	}
3320}
3321
3322static void crypt_postsuspend(struct dm_target *ti)
3323{
3324	struct crypt_config *cc = ti->private;
3325
3326	set_bit(DM_CRYPT_SUSPENDED, &cc->flags);
3327}
3328
3329static int crypt_preresume(struct dm_target *ti)
3330{
3331	struct crypt_config *cc = ti->private;
3332
3333	if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) {
3334		DMERR("aborting resume - crypt key is not set.");
3335		return -EAGAIN;
3336	}
3337
3338	return 0;
3339}
3340
3341static void crypt_resume(struct dm_target *ti)
3342{
3343	struct crypt_config *cc = ti->private;
3344
3345	clear_bit(DM_CRYPT_SUSPENDED, &cc->flags);
3346}
3347
3348/* Message interface
3349 *	key set <key>
3350 *	key wipe
3351 */
3352static int crypt_message(struct dm_target *ti, unsigned argc, char **argv,
3353			 char *result, unsigned maxlen)
3354{
3355	struct crypt_config *cc = ti->private;
3356	int key_size, ret = -EINVAL;
3357
3358	if (argc < 2)
3359		goto error;
3360
3361	if (!strcasecmp(argv[0], "key")) {
3362		if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) {
3363			DMWARN("not suspended during key manipulation.");
3364			return -EINVAL;
3365		}
3366		if (argc == 3 && !strcasecmp(argv[1], "set")) {
3367			/* The key size may not be changed. */
3368			key_size = get_key_size(&argv[2]);
3369			if (key_size < 0 || cc->key_size != key_size) {
3370				memset(argv[2], '0', strlen(argv[2]));
3371				return -EINVAL;
3372			}
3373
3374			ret = crypt_set_key(cc, argv[2]);
3375			if (ret)
3376				return ret;
3377			if (cc->iv_gen_ops && cc->iv_gen_ops->init)
3378				ret = cc->iv_gen_ops->init(cc);
3379			/* wipe the kernel key payload copy */
3380			if (cc->key_string)
3381				memset(cc->key, 0, cc->key_size * sizeof(u8));
3382			return ret;
3383		}
3384		if (argc == 2 && !strcasecmp(argv[1], "wipe"))
3385			return crypt_wipe_key(cc);
3386	}
3387
3388error:
3389	DMWARN("unrecognised message received.");
3390	return -EINVAL;
3391}
3392
3393static int crypt_iterate_devices(struct dm_target *ti,
3394				 iterate_devices_callout_fn fn, void *data)
3395{
3396	struct crypt_config *cc = ti->private;
3397
3398	return fn(ti, cc->dev, cc->start, ti->len, data);
3399}
3400
3401static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits)
3402{
3403	struct crypt_config *cc = ti->private;
3404
3405	/*
3406	 * Unfortunate constraint that is required to avoid the potential
3407	 * for exceeding underlying device's max_segments limits -- due to
3408	 * crypt_alloc_buffer() possibly allocating pages for the encryption
3409	 * bio that are not as physically contiguous as the original bio.
3410	 */
3411	limits->max_segment_size = PAGE_SIZE;
3412
3413	limits->logical_block_size =
3414		max_t(unsigned, limits->logical_block_size, cc->sector_size);
3415	limits->physical_block_size =
3416		max_t(unsigned, limits->physical_block_size, cc->sector_size);
3417	limits->io_min = max_t(unsigned, limits->io_min, cc->sector_size);
 
3418}
3419
3420static struct target_type crypt_target = {
3421	.name   = "crypt",
3422	.version = {1, 22, 0},
3423	.module = THIS_MODULE,
3424	.ctr    = crypt_ctr,
3425	.dtr    = crypt_dtr,
3426#ifdef CONFIG_BLK_DEV_ZONED
3427	.features = DM_TARGET_ZONED_HM,
3428	.report_zones = crypt_report_zones,
3429#endif
3430	.map    = crypt_map,
3431	.status = crypt_status,
3432	.postsuspend = crypt_postsuspend,
3433	.preresume = crypt_preresume,
3434	.resume = crypt_resume,
3435	.message = crypt_message,
3436	.iterate_devices = crypt_iterate_devices,
3437	.io_hints = crypt_io_hints,
3438};
3439
3440static int __init dm_crypt_init(void)
3441{
3442	int r;
3443
3444	r = dm_register_target(&crypt_target);
3445	if (r < 0)
3446		DMERR("register failed %d", r);
3447
3448	return r;
3449}
3450
3451static void __exit dm_crypt_exit(void)
3452{
3453	dm_unregister_target(&crypt_target);
3454}
3455
3456module_init(dm_crypt_init);
3457module_exit(dm_crypt_exit);
3458
3459MODULE_AUTHOR("Jana Saout <jana@saout.de>");
3460MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption");
3461MODULE_LICENSE("GPL");
v6.8
   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * Copyright (C) 2003 Jana Saout <jana@saout.de>
   4 * Copyright (C) 2004 Clemens Fruhwirth <clemens@endorphin.org>
   5 * Copyright (C) 2006-2020 Red Hat, Inc. All rights reserved.
   6 * Copyright (C) 2013-2020 Milan Broz <gmazyland@gmail.com>
   7 *
   8 * This file is released under the GPL.
   9 */
  10
  11#include <linux/completion.h>
  12#include <linux/err.h>
  13#include <linux/module.h>
  14#include <linux/init.h>
  15#include <linux/kernel.h>
  16#include <linux/key.h>
  17#include <linux/bio.h>
  18#include <linux/blkdev.h>
  19#include <linux/blk-integrity.h>
  20#include <linux/mempool.h>
  21#include <linux/slab.h>
  22#include <linux/crypto.h>
  23#include <linux/workqueue.h>
  24#include <linux/kthread.h>
  25#include <linux/backing-dev.h>
  26#include <linux/atomic.h>
  27#include <linux/scatterlist.h>
  28#include <linux/rbtree.h>
  29#include <linux/ctype.h>
  30#include <asm/page.h>
  31#include <asm/unaligned.h>
  32#include <crypto/hash.h>
  33#include <crypto/md5.h>
 
  34#include <crypto/skcipher.h>
  35#include <crypto/aead.h>
  36#include <crypto/authenc.h>
  37#include <crypto/utils.h>
  38#include <linux/rtnetlink.h> /* for struct rtattr and RTA macros only */
  39#include <linux/key-type.h>
  40#include <keys/user-type.h>
  41#include <keys/encrypted-type.h>
  42#include <keys/trusted-type.h>
  43
  44#include <linux/device-mapper.h>
  45
  46#include "dm-audit.h"
  47
  48#define DM_MSG_PREFIX "crypt"
  49
  50/*
  51 * context holding the current state of a multi-part conversion
  52 */
  53struct convert_context {
  54	struct completion restart;
  55	struct bio *bio_in;
 
  56	struct bvec_iter iter_in;
  57	struct bio *bio_out;
  58	struct bvec_iter iter_out;
 
  59	atomic_t cc_pending;
  60	u64 cc_sector;
  61	union {
  62		struct skcipher_request *req;
  63		struct aead_request *req_aead;
  64	} r;
  65	bool aead_recheck;
  66	bool aead_failed;
  67
  68};
  69
  70/*
  71 * per bio private data
  72 */
  73struct dm_crypt_io {
  74	struct crypt_config *cc;
  75	struct bio *base_bio;
  76	u8 *integrity_metadata;
  77	bool integrity_metadata_from_pool:1;
  78
  79	struct work_struct work;
 
  80
  81	struct convert_context ctx;
  82
  83	atomic_t io_pending;
  84	blk_status_t error;
  85	sector_t sector;
  86
  87	struct bvec_iter saved_bi_iter;
  88
  89	struct rb_node rb_node;
  90} CRYPTO_MINALIGN_ATTR;
  91
  92struct dm_crypt_request {
  93	struct convert_context *ctx;
  94	struct scatterlist sg_in[4];
  95	struct scatterlist sg_out[4];
  96	u64 iv_sector;
  97};
  98
  99struct crypt_config;
 100
 101struct crypt_iv_operations {
 102	int (*ctr)(struct crypt_config *cc, struct dm_target *ti,
 103		   const char *opts);
 104	void (*dtr)(struct crypt_config *cc);
 105	int (*init)(struct crypt_config *cc);
 106	int (*wipe)(struct crypt_config *cc);
 107	int (*generator)(struct crypt_config *cc, u8 *iv,
 108			 struct dm_crypt_request *dmreq);
 109	int (*post)(struct crypt_config *cc, u8 *iv,
 110		    struct dm_crypt_request *dmreq);
 111};
 112
 113struct iv_benbi_private {
 114	int shift;
 115};
 116
 117#define LMK_SEED_SIZE 64 /* hash + 0 */
 118struct iv_lmk_private {
 119	struct crypto_shash *hash_tfm;
 120	u8 *seed;
 121};
 122
 123#define TCW_WHITENING_SIZE 16
 124struct iv_tcw_private {
 125	struct crypto_shash *crc32_tfm;
 126	u8 *iv_seed;
 127	u8 *whitening;
 128};
 129
 130#define ELEPHANT_MAX_KEY_SIZE 32
 131struct iv_elephant_private {
 132	struct crypto_skcipher *tfm;
 133};
 134
 135/*
 136 * Crypt: maps a linear range of a block device
 137 * and encrypts / decrypts at the same time.
 138 */
 139enum flags { DM_CRYPT_SUSPENDED, DM_CRYPT_KEY_VALID,
 140	     DM_CRYPT_SAME_CPU, DM_CRYPT_NO_OFFLOAD,
 141	     DM_CRYPT_NO_READ_WORKQUEUE, DM_CRYPT_NO_WRITE_WORKQUEUE,
 142	     DM_CRYPT_WRITE_INLINE };
 143
 144enum cipher_flags {
 145	CRYPT_MODE_INTEGRITY_AEAD,	/* Use authenticated mode for cipher */
 146	CRYPT_IV_LARGE_SECTORS,		/* Calculate IV from sector_size, not 512B sectors */
 147	CRYPT_ENCRYPT_PREPROCESS,	/* Must preprocess data for encryption (elephant) */
 148};
 149
 150/*
 151 * The fields in here must be read only after initialization.
 152 */
 153struct crypt_config {
 154	struct dm_dev *dev;
 155	sector_t start;
 156
 157	struct percpu_counter n_allocated_pages;
 158
 159	struct workqueue_struct *io_queue;
 160	struct workqueue_struct *crypt_queue;
 161
 162	spinlock_t write_thread_lock;
 163	struct task_struct *write_thread;
 164	struct rb_root write_tree;
 165
 166	char *cipher_string;
 167	char *cipher_auth;
 168	char *key_string;
 169
 170	const struct crypt_iv_operations *iv_gen_ops;
 171	union {
 172		struct iv_benbi_private benbi;
 173		struct iv_lmk_private lmk;
 174		struct iv_tcw_private tcw;
 175		struct iv_elephant_private elephant;
 176	} iv_gen_private;
 177	u64 iv_offset;
 178	unsigned int iv_size;
 179	unsigned short sector_size;
 180	unsigned char sector_shift;
 181
 182	union {
 183		struct crypto_skcipher **tfms;
 184		struct crypto_aead **tfms_aead;
 185	} cipher_tfm;
 186	unsigned int tfms_count;
 187	unsigned long cipher_flags;
 188
 189	/*
 190	 * Layout of each crypto request:
 191	 *
 192	 *   struct skcipher_request
 193	 *      context
 194	 *      padding
 195	 *   struct dm_crypt_request
 196	 *      padding
 197	 *   IV
 198	 *
 199	 * The padding is added so that dm_crypt_request and the IV are
 200	 * correctly aligned.
 201	 */
 202	unsigned int dmreq_start;
 203
 204	unsigned int per_bio_data_size;
 205
 206	unsigned long flags;
 207	unsigned int key_size;
 208	unsigned int key_parts;      /* independent parts in key buffer */
 209	unsigned int key_extra_size; /* additional keys length */
 210	unsigned int key_mac_size;   /* MAC key size for authenc(...) */
 211
 212	unsigned int integrity_tag_size;
 213	unsigned int integrity_iv_size;
 214	unsigned int on_disk_tag_size;
 215
 216	/*
 217	 * pool for per bio private data, crypto requests,
 218	 * encryption requeusts/buffer pages and integrity tags
 219	 */
 220	unsigned int tag_pool_max_sectors;
 221	mempool_t tag_pool;
 222	mempool_t req_pool;
 223	mempool_t page_pool;
 224
 225	struct bio_set bs;
 226	struct mutex bio_alloc_lock;
 227
 228	u8 *authenc_key; /* space for keys in authenc() format (if used) */
 229	u8 key[] __counted_by(key_size);
 230};
 231
 232#define MIN_IOS		64
 233#define MAX_TAG_SIZE	480
 234#define POOL_ENTRY_SIZE	512
 235
 236static DEFINE_SPINLOCK(dm_crypt_clients_lock);
 237static unsigned int dm_crypt_clients_n;
 238static volatile unsigned long dm_crypt_pages_per_client;
 239#define DM_CRYPT_MEMORY_PERCENT			2
 240#define DM_CRYPT_MIN_PAGES_PER_CLIENT		(BIO_MAX_VECS * 16)
 241
 242static void crypt_endio(struct bio *clone);
 243static void kcryptd_queue_crypt(struct dm_crypt_io *io);
 244static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc,
 245					     struct scatterlist *sg);
 246
 247static bool crypt_integrity_aead(struct crypt_config *cc);
 248
 249/*
 250 * Use this to access cipher attributes that are independent of the key.
 251 */
 252static struct crypto_skcipher *any_tfm(struct crypt_config *cc)
 253{
 254	return cc->cipher_tfm.tfms[0];
 255}
 256
 257static struct crypto_aead *any_tfm_aead(struct crypt_config *cc)
 258{
 259	return cc->cipher_tfm.tfms_aead[0];
 260}
 261
 262/*
 263 * Different IV generation algorithms:
 264 *
 265 * plain: the initial vector is the 32-bit little-endian version of the sector
 266 *        number, padded with zeros if necessary.
 267 *
 268 * plain64: the initial vector is the 64-bit little-endian version of the sector
 269 *        number, padded with zeros if necessary.
 270 *
 271 * plain64be: the initial vector is the 64-bit big-endian version of the sector
 272 *        number, padded with zeros if necessary.
 273 *
 274 * essiv: "encrypted sector|salt initial vector", the sector number is
 275 *        encrypted with the bulk cipher using a salt as key. The salt
 276 *        should be derived from the bulk cipher's key via hashing.
 277 *
 278 * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1
 279 *        (needed for LRW-32-AES and possible other narrow block modes)
 280 *
 281 * null: the initial vector is always zero.  Provides compatibility with
 282 *       obsolete loop_fish2 devices.  Do not use for new devices.
 283 *
 284 * lmk:  Compatible implementation of the block chaining mode used
 285 *       by the Loop-AES block device encryption system
 286 *       designed by Jari Ruusu. See http://loop-aes.sourceforge.net/
 287 *       It operates on full 512 byte sectors and uses CBC
 288 *       with an IV derived from the sector number, the data and
 289 *       optionally extra IV seed.
 290 *       This means that after decryption the first block
 291 *       of sector must be tweaked according to decrypted data.
 292 *       Loop-AES can use three encryption schemes:
 293 *         version 1: is plain aes-cbc mode
 294 *         version 2: uses 64 multikey scheme with lmk IV generator
 295 *         version 3: the same as version 2 with additional IV seed
 296 *                   (it uses 65 keys, last key is used as IV seed)
 297 *
 298 * tcw:  Compatible implementation of the block chaining mode used
 299 *       by the TrueCrypt device encryption system (prior to version 4.1).
 300 *       For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat
 301 *       It operates on full 512 byte sectors and uses CBC
 302 *       with an IV derived from initial key and the sector number.
 303 *       In addition, whitening value is applied on every sector, whitening
 304 *       is calculated from initial key, sector number and mixed using CRC32.
 305 *       Note that this encryption scheme is vulnerable to watermarking attacks
 306 *       and should be used for old compatible containers access only.
 307 *
 308 * eboiv: Encrypted byte-offset IV (used in Bitlocker in CBC mode)
 309 *        The IV is encrypted little-endian byte-offset (with the same key
 310 *        and cipher as the volume).
 311 *
 312 * elephant: The extended version of eboiv with additional Elephant diffuser
 313 *           used with Bitlocker CBC mode.
 314 *           This mode was used in older Windows systems
 315 *           https://download.microsoft.com/download/0/2/3/0238acaf-d3bf-4a6d-b3d6-0a0be4bbb36e/bitlockercipher200608.pdf
 316 */
 317
 318static int crypt_iv_plain_gen(struct crypt_config *cc, u8 *iv,
 319			      struct dm_crypt_request *dmreq)
 320{
 321	memset(iv, 0, cc->iv_size);
 322	*(__le32 *)iv = cpu_to_le32(dmreq->iv_sector & 0xffffffff);
 323
 324	return 0;
 325}
 326
 327static int crypt_iv_plain64_gen(struct crypt_config *cc, u8 *iv,
 328				struct dm_crypt_request *dmreq)
 329{
 330	memset(iv, 0, cc->iv_size);
 331	*(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
 332
 333	return 0;
 334}
 335
 336static int crypt_iv_plain64be_gen(struct crypt_config *cc, u8 *iv,
 337				  struct dm_crypt_request *dmreq)
 338{
 339	memset(iv, 0, cc->iv_size);
 340	/* iv_size is at least of size u64; usually it is 16 bytes */
 341	*(__be64 *)&iv[cc->iv_size - sizeof(u64)] = cpu_to_be64(dmreq->iv_sector);
 342
 343	return 0;
 344}
 345
 346static int crypt_iv_essiv_gen(struct crypt_config *cc, u8 *iv,
 347			      struct dm_crypt_request *dmreq)
 348{
 349	/*
 350	 * ESSIV encryption of the IV is now handled by the crypto API,
 351	 * so just pass the plain sector number here.
 352	 */
 353	memset(iv, 0, cc->iv_size);
 354	*(__le64 *)iv = cpu_to_le64(dmreq->iv_sector);
 355
 356	return 0;
 357}
 358
 359static int crypt_iv_benbi_ctr(struct crypt_config *cc, struct dm_target *ti,
 360			      const char *opts)
 361{
 362	unsigned int bs;
 363	int log;
 364
 365	if (crypt_integrity_aead(cc))
 366		bs = crypto_aead_blocksize(any_tfm_aead(cc));
 367	else
 368		bs = crypto_skcipher_blocksize(any_tfm(cc));
 369	log = ilog2(bs);
 370
 371	/*
 372	 * We need to calculate how far we must shift the sector count
 373	 * to get the cipher block count, we use this shift in _gen.
 374	 */
 375	if (1 << log != bs) {
 376		ti->error = "cypher blocksize is not a power of 2";
 377		return -EINVAL;
 378	}
 379
 380	if (log > 9) {
 381		ti->error = "cypher blocksize is > 512";
 382		return -EINVAL;
 383	}
 384
 385	cc->iv_gen_private.benbi.shift = 9 - log;
 386
 387	return 0;
 388}
 389
 390static void crypt_iv_benbi_dtr(struct crypt_config *cc)
 391{
 392}
 393
 394static int crypt_iv_benbi_gen(struct crypt_config *cc, u8 *iv,
 395			      struct dm_crypt_request *dmreq)
 396{
 397	__be64 val;
 398
 399	memset(iv, 0, cc->iv_size - sizeof(u64)); /* rest is cleared below */
 400
 401	val = cpu_to_be64(((u64)dmreq->iv_sector << cc->iv_gen_private.benbi.shift) + 1);
 402	put_unaligned(val, (__be64 *)(iv + cc->iv_size - sizeof(u64)));
 403
 404	return 0;
 405}
 406
 407static int crypt_iv_null_gen(struct crypt_config *cc, u8 *iv,
 408			     struct dm_crypt_request *dmreq)
 409{
 410	memset(iv, 0, cc->iv_size);
 411
 412	return 0;
 413}
 414
 415static void crypt_iv_lmk_dtr(struct crypt_config *cc)
 416{
 417	struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
 418
 419	if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm))
 420		crypto_free_shash(lmk->hash_tfm);
 421	lmk->hash_tfm = NULL;
 422
 423	kfree_sensitive(lmk->seed);
 424	lmk->seed = NULL;
 425}
 426
 427static int crypt_iv_lmk_ctr(struct crypt_config *cc, struct dm_target *ti,
 428			    const char *opts)
 429{
 430	struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
 431
 432	if (cc->sector_size != (1 << SECTOR_SHIFT)) {
 433		ti->error = "Unsupported sector size for LMK";
 434		return -EINVAL;
 435	}
 436
 437	lmk->hash_tfm = crypto_alloc_shash("md5", 0,
 438					   CRYPTO_ALG_ALLOCATES_MEMORY);
 439	if (IS_ERR(lmk->hash_tfm)) {
 440		ti->error = "Error initializing LMK hash";
 441		return PTR_ERR(lmk->hash_tfm);
 442	}
 443
 444	/* No seed in LMK version 2 */
 445	if (cc->key_parts == cc->tfms_count) {
 446		lmk->seed = NULL;
 447		return 0;
 448	}
 449
 450	lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL);
 451	if (!lmk->seed) {
 452		crypt_iv_lmk_dtr(cc);
 453		ti->error = "Error kmallocing seed storage in LMK";
 454		return -ENOMEM;
 455	}
 456
 457	return 0;
 458}
 459
 460static int crypt_iv_lmk_init(struct crypt_config *cc)
 461{
 462	struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
 463	int subkey_size = cc->key_size / cc->key_parts;
 464
 465	/* LMK seed is on the position of LMK_KEYS + 1 key */
 466	if (lmk->seed)
 467		memcpy(lmk->seed, cc->key + (cc->tfms_count * subkey_size),
 468		       crypto_shash_digestsize(lmk->hash_tfm));
 469
 470	return 0;
 471}
 472
 473static int crypt_iv_lmk_wipe(struct crypt_config *cc)
 474{
 475	struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
 476
 477	if (lmk->seed)
 478		memset(lmk->seed, 0, LMK_SEED_SIZE);
 479
 480	return 0;
 481}
 482
 483static int crypt_iv_lmk_one(struct crypt_config *cc, u8 *iv,
 484			    struct dm_crypt_request *dmreq,
 485			    u8 *data)
 486{
 487	struct iv_lmk_private *lmk = &cc->iv_gen_private.lmk;
 488	SHASH_DESC_ON_STACK(desc, lmk->hash_tfm);
 489	struct md5_state md5state;
 490	__le32 buf[4];
 491	int i, r;
 492
 493	desc->tfm = lmk->hash_tfm;
 494
 495	r = crypto_shash_init(desc);
 496	if (r)
 497		return r;
 498
 499	if (lmk->seed) {
 500		r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE);
 501		if (r)
 502			return r;
 503	}
 504
 505	/* Sector is always 512B, block size 16, add data of blocks 1-31 */
 506	r = crypto_shash_update(desc, data + 16, 16 * 31);
 507	if (r)
 508		return r;
 509
 510	/* Sector is cropped to 56 bits here */
 511	buf[0] = cpu_to_le32(dmreq->iv_sector & 0xFFFFFFFF);
 512	buf[1] = cpu_to_le32((((u64)dmreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000);
 513	buf[2] = cpu_to_le32(4024);
 514	buf[3] = 0;
 515	r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf));
 516	if (r)
 517		return r;
 518
 519	/* No MD5 padding here */
 520	r = crypto_shash_export(desc, &md5state);
 521	if (r)
 522		return r;
 523
 524	for (i = 0; i < MD5_HASH_WORDS; i++)
 525		__cpu_to_le32s(&md5state.hash[i]);
 526	memcpy(iv, &md5state.hash, cc->iv_size);
 527
 528	return 0;
 529}
 530
 531static int crypt_iv_lmk_gen(struct crypt_config *cc, u8 *iv,
 532			    struct dm_crypt_request *dmreq)
 533{
 534	struct scatterlist *sg;
 535	u8 *src;
 536	int r = 0;
 537
 538	if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
 539		sg = crypt_get_sg_data(cc, dmreq->sg_in);
 540		src = kmap_local_page(sg_page(sg));
 541		r = crypt_iv_lmk_one(cc, iv, dmreq, src + sg->offset);
 542		kunmap_local(src);
 543	} else
 544		memset(iv, 0, cc->iv_size);
 545
 546	return r;
 547}
 548
 549static int crypt_iv_lmk_post(struct crypt_config *cc, u8 *iv,
 550			     struct dm_crypt_request *dmreq)
 551{
 552	struct scatterlist *sg;
 553	u8 *dst;
 554	int r;
 555
 556	if (bio_data_dir(dmreq->ctx->bio_in) == WRITE)
 557		return 0;
 558
 559	sg = crypt_get_sg_data(cc, dmreq->sg_out);
 560	dst = kmap_local_page(sg_page(sg));
 561	r = crypt_iv_lmk_one(cc, iv, dmreq, dst + sg->offset);
 562
 563	/* Tweak the first block of plaintext sector */
 564	if (!r)
 565		crypto_xor(dst + sg->offset, iv, cc->iv_size);
 566
 567	kunmap_local(dst);
 568	return r;
 569}
 570
 571static void crypt_iv_tcw_dtr(struct crypt_config *cc)
 572{
 573	struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
 574
 575	kfree_sensitive(tcw->iv_seed);
 576	tcw->iv_seed = NULL;
 577	kfree_sensitive(tcw->whitening);
 578	tcw->whitening = NULL;
 579
 580	if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm))
 581		crypto_free_shash(tcw->crc32_tfm);
 582	tcw->crc32_tfm = NULL;
 583}
 584
 585static int crypt_iv_tcw_ctr(struct crypt_config *cc, struct dm_target *ti,
 586			    const char *opts)
 587{
 588	struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
 589
 590	if (cc->sector_size != (1 << SECTOR_SHIFT)) {
 591		ti->error = "Unsupported sector size for TCW";
 592		return -EINVAL;
 593	}
 594
 595	if (cc->key_size <= (cc->iv_size + TCW_WHITENING_SIZE)) {
 596		ti->error = "Wrong key size for TCW";
 597		return -EINVAL;
 598	}
 599
 600	tcw->crc32_tfm = crypto_alloc_shash("crc32", 0,
 601					    CRYPTO_ALG_ALLOCATES_MEMORY);
 602	if (IS_ERR(tcw->crc32_tfm)) {
 603		ti->error = "Error initializing CRC32 in TCW";
 604		return PTR_ERR(tcw->crc32_tfm);
 605	}
 606
 607	tcw->iv_seed = kzalloc(cc->iv_size, GFP_KERNEL);
 608	tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL);
 609	if (!tcw->iv_seed || !tcw->whitening) {
 610		crypt_iv_tcw_dtr(cc);
 611		ti->error = "Error allocating seed storage in TCW";
 612		return -ENOMEM;
 613	}
 614
 615	return 0;
 616}
 617
 618static int crypt_iv_tcw_init(struct crypt_config *cc)
 619{
 620	struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
 621	int key_offset = cc->key_size - cc->iv_size - TCW_WHITENING_SIZE;
 622
 623	memcpy(tcw->iv_seed, &cc->key[key_offset], cc->iv_size);
 624	memcpy(tcw->whitening, &cc->key[key_offset + cc->iv_size],
 625	       TCW_WHITENING_SIZE);
 626
 627	return 0;
 628}
 629
 630static int crypt_iv_tcw_wipe(struct crypt_config *cc)
 631{
 632	struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
 633
 634	memset(tcw->iv_seed, 0, cc->iv_size);
 635	memset(tcw->whitening, 0, TCW_WHITENING_SIZE);
 636
 637	return 0;
 638}
 639
 640static int crypt_iv_tcw_whitening(struct crypt_config *cc,
 641				  struct dm_crypt_request *dmreq,
 642				  u8 *data)
 643{
 644	struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
 645	__le64 sector = cpu_to_le64(dmreq->iv_sector);
 646	u8 buf[TCW_WHITENING_SIZE];
 647	SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm);
 648	int i, r;
 649
 650	/* xor whitening with sector number */
 651	crypto_xor_cpy(buf, tcw->whitening, (u8 *)&sector, 8);
 652	crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)&sector, 8);
 653
 654	/* calculate crc32 for every 32bit part and xor it */
 655	desc->tfm = tcw->crc32_tfm;
 656	for (i = 0; i < 4; i++) {
 657		r = crypto_shash_digest(desc, &buf[i * 4], 4, &buf[i * 4]);
 
 
 
 
 
 
 658		if (r)
 659			goto out;
 660	}
 661	crypto_xor(&buf[0], &buf[12], 4);
 662	crypto_xor(&buf[4], &buf[8], 4);
 663
 664	/* apply whitening (8 bytes) to whole sector */
 665	for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++)
 666		crypto_xor(data + i * 8, buf, 8);
 667out:
 668	memzero_explicit(buf, sizeof(buf));
 669	return r;
 670}
 671
 672static int crypt_iv_tcw_gen(struct crypt_config *cc, u8 *iv,
 673			    struct dm_crypt_request *dmreq)
 674{
 675	struct scatterlist *sg;
 676	struct iv_tcw_private *tcw = &cc->iv_gen_private.tcw;
 677	__le64 sector = cpu_to_le64(dmreq->iv_sector);
 678	u8 *src;
 679	int r = 0;
 680
 681	/* Remove whitening from ciphertext */
 682	if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) {
 683		sg = crypt_get_sg_data(cc, dmreq->sg_in);
 684		src = kmap_local_page(sg_page(sg));
 685		r = crypt_iv_tcw_whitening(cc, dmreq, src + sg->offset);
 686		kunmap_local(src);
 687	}
 688
 689	/* Calculate IV */
 690	crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)&sector, 8);
 691	if (cc->iv_size > 8)
 692		crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)&sector,
 693			       cc->iv_size - 8);
 694
 695	return r;
 696}
 697
 698static int crypt_iv_tcw_post(struct crypt_config *cc, u8 *iv,
 699			     struct dm_crypt_request *dmreq)
 700{
 701	struct scatterlist *sg;
 702	u8 *dst;
 703	int r;
 704
 705	if (bio_data_dir(dmreq->ctx->bio_in) != WRITE)
 706		return 0;
 707
 708	/* Apply whitening on ciphertext */
 709	sg = crypt_get_sg_data(cc, dmreq->sg_out);
 710	dst = kmap_local_page(sg_page(sg));
 711	r = crypt_iv_tcw_whitening(cc, dmreq, dst + sg->offset);
 712	kunmap_local(dst);
 713
 714	return r;
 715}
 716
 717static int crypt_iv_random_gen(struct crypt_config *cc, u8 *iv,
 718				struct dm_crypt_request *dmreq)
 719{
 720	/* Used only for writes, there must be an additional space to store IV */
 721	get_random_bytes(iv, cc->iv_size);
 722	return 0;
 723}
 724
 725static int crypt_iv_eboiv_ctr(struct crypt_config *cc, struct dm_target *ti,
 726			    const char *opts)
 727{
 728	if (crypt_integrity_aead(cc)) {
 729		ti->error = "AEAD transforms not supported for EBOIV";
 730		return -EINVAL;
 731	}
 732
 733	if (crypto_skcipher_blocksize(any_tfm(cc)) != cc->iv_size) {
 734		ti->error = "Block size of EBOIV cipher does not match IV size of block cipher";
 
 735		return -EINVAL;
 736	}
 737
 738	return 0;
 739}
 740
 741static int crypt_iv_eboiv_gen(struct crypt_config *cc, u8 *iv,
 742			    struct dm_crypt_request *dmreq)
 743{
 744	struct crypto_skcipher *tfm = any_tfm(cc);
 745	struct skcipher_request *req;
 746	struct scatterlist src, dst;
 747	DECLARE_CRYPTO_WAIT(wait);
 748	unsigned int reqsize;
 749	int err;
 750	u8 *buf;
 751
 752	reqsize = sizeof(*req) + crypto_skcipher_reqsize(tfm);
 753	reqsize = ALIGN(reqsize, __alignof__(__le64));
 754
 755	req = kmalloc(reqsize + cc->iv_size, GFP_NOIO);
 756	if (!req)
 757		return -ENOMEM;
 758
 759	skcipher_request_set_tfm(req, tfm);
 760
 761	buf = (u8 *)req + reqsize;
 762	memset(buf, 0, cc->iv_size);
 763	*(__le64 *)buf = cpu_to_le64(dmreq->iv_sector * cc->sector_size);
 764
 765	sg_init_one(&src, page_address(ZERO_PAGE(0)), cc->iv_size);
 766	sg_init_one(&dst, iv, cc->iv_size);
 767	skcipher_request_set_crypt(req, &src, &dst, cc->iv_size, buf);
 768	skcipher_request_set_callback(req, 0, crypto_req_done, &wait);
 769	err = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
 770	kfree_sensitive(req);
 771
 772	return err;
 773}
 774
 775static void crypt_iv_elephant_dtr(struct crypt_config *cc)
 776{
 777	struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
 778
 779	crypto_free_skcipher(elephant->tfm);
 780	elephant->tfm = NULL;
 781}
 782
 783static int crypt_iv_elephant_ctr(struct crypt_config *cc, struct dm_target *ti,
 784			    const char *opts)
 785{
 786	struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
 787	int r;
 788
 789	elephant->tfm = crypto_alloc_skcipher("ecb(aes)", 0,
 790					      CRYPTO_ALG_ALLOCATES_MEMORY);
 791	if (IS_ERR(elephant->tfm)) {
 792		r = PTR_ERR(elephant->tfm);
 793		elephant->tfm = NULL;
 794		return r;
 795	}
 796
 797	r = crypt_iv_eboiv_ctr(cc, ti, NULL);
 798	if (r)
 799		crypt_iv_elephant_dtr(cc);
 800	return r;
 801}
 802
 803static void diffuser_disk_to_cpu(u32 *d, size_t n)
 804{
 805#ifndef __LITTLE_ENDIAN
 806	int i;
 807
 808	for (i = 0; i < n; i++)
 809		d[i] = le32_to_cpu((__le32)d[i]);
 810#endif
 811}
 812
 813static void diffuser_cpu_to_disk(__le32 *d, size_t n)
 814{
 815#ifndef __LITTLE_ENDIAN
 816	int i;
 817
 818	for (i = 0; i < n; i++)
 819		d[i] = cpu_to_le32((u32)d[i]);
 820#endif
 821}
 822
 823static void diffuser_a_decrypt(u32 *d, size_t n)
 824{
 825	int i, i1, i2, i3;
 826
 827	for (i = 0; i < 5; i++) {
 828		i1 = 0;
 829		i2 = n - 2;
 830		i3 = n - 5;
 831
 832		while (i1 < (n - 1)) {
 833			d[i1] += d[i2] ^ (d[i3] << 9 | d[i3] >> 23);
 834			i1++; i2++; i3++;
 835
 836			if (i3 >= n)
 837				i3 -= n;
 838
 839			d[i1] += d[i2] ^ d[i3];
 840			i1++; i2++; i3++;
 841
 842			if (i2 >= n)
 843				i2 -= n;
 844
 845			d[i1] += d[i2] ^ (d[i3] << 13 | d[i3] >> 19);
 846			i1++; i2++; i3++;
 847
 848			d[i1] += d[i2] ^ d[i3];
 849			i1++; i2++; i3++;
 850		}
 851	}
 852}
 853
 854static void diffuser_a_encrypt(u32 *d, size_t n)
 855{
 856	int i, i1, i2, i3;
 857
 858	for (i = 0; i < 5; i++) {
 859		i1 = n - 1;
 860		i2 = n - 2 - 1;
 861		i3 = n - 5 - 1;
 862
 863		while (i1 > 0) {
 864			d[i1] -= d[i2] ^ d[i3];
 865			i1--; i2--; i3--;
 866
 867			d[i1] -= d[i2] ^ (d[i3] << 13 | d[i3] >> 19);
 868			i1--; i2--; i3--;
 869
 870			if (i2 < 0)
 871				i2 += n;
 872
 873			d[i1] -= d[i2] ^ d[i3];
 874			i1--; i2--; i3--;
 875
 876			if (i3 < 0)
 877				i3 += n;
 878
 879			d[i1] -= d[i2] ^ (d[i3] << 9 | d[i3] >> 23);
 880			i1--; i2--; i3--;
 881		}
 882	}
 883}
 884
 885static void diffuser_b_decrypt(u32 *d, size_t n)
 886{
 887	int i, i1, i2, i3;
 888
 889	for (i = 0; i < 3; i++) {
 890		i1 = 0;
 891		i2 = 2;
 892		i3 = 5;
 893
 894		while (i1 < (n - 1)) {
 895			d[i1] += d[i2] ^ d[i3];
 896			i1++; i2++; i3++;
 897
 898			d[i1] += d[i2] ^ (d[i3] << 10 | d[i3] >> 22);
 899			i1++; i2++; i3++;
 900
 901			if (i2 >= n)
 902				i2 -= n;
 903
 904			d[i1] += d[i2] ^ d[i3];
 905			i1++; i2++; i3++;
 906
 907			if (i3 >= n)
 908				i3 -= n;
 909
 910			d[i1] += d[i2] ^ (d[i3] << 25 | d[i3] >> 7);
 911			i1++; i2++; i3++;
 912		}
 913	}
 914}
 915
 916static void diffuser_b_encrypt(u32 *d, size_t n)
 917{
 918	int i, i1, i2, i3;
 919
 920	for (i = 0; i < 3; i++) {
 921		i1 = n - 1;
 922		i2 = 2 - 1;
 923		i3 = 5 - 1;
 924
 925		while (i1 > 0) {
 926			d[i1] -= d[i2] ^ (d[i3] << 25 | d[i3] >> 7);
 927			i1--; i2--; i3--;
 928
 929			if (i3 < 0)
 930				i3 += n;
 931
 932			d[i1] -= d[i2] ^ d[i3];
 933			i1--; i2--; i3--;
 934
 935			if (i2 < 0)
 936				i2 += n;
 937
 938			d[i1] -= d[i2] ^ (d[i3] << 10 | d[i3] >> 22);
 939			i1--; i2--; i3--;
 940
 941			d[i1] -= d[i2] ^ d[i3];
 942			i1--; i2--; i3--;
 943		}
 944	}
 945}
 946
 947static int crypt_iv_elephant(struct crypt_config *cc, struct dm_crypt_request *dmreq)
 948{
 949	struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
 950	u8 *es, *ks, *data, *data2, *data_offset;
 951	struct skcipher_request *req;
 952	struct scatterlist *sg, *sg2, src, dst;
 953	DECLARE_CRYPTO_WAIT(wait);
 954	int i, r;
 955
 956	req = skcipher_request_alloc(elephant->tfm, GFP_NOIO);
 957	es = kzalloc(16, GFP_NOIO); /* Key for AES */
 958	ks = kzalloc(32, GFP_NOIO); /* Elephant sector key */
 959
 960	if (!req || !es || !ks) {
 961		r = -ENOMEM;
 962		goto out;
 963	}
 964
 965	*(__le64 *)es = cpu_to_le64(dmreq->iv_sector * cc->sector_size);
 966
 967	/* E(Ks, e(s)) */
 968	sg_init_one(&src, es, 16);
 969	sg_init_one(&dst, ks, 16);
 970	skcipher_request_set_crypt(req, &src, &dst, 16, NULL);
 971	skcipher_request_set_callback(req, 0, crypto_req_done, &wait);
 972	r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
 973	if (r)
 974		goto out;
 975
 976	/* E(Ks, e'(s)) */
 977	es[15] = 0x80;
 978	sg_init_one(&dst, &ks[16], 16);
 979	r = crypto_wait_req(crypto_skcipher_encrypt(req), &wait);
 980	if (r)
 981		goto out;
 982
 983	sg = crypt_get_sg_data(cc, dmreq->sg_out);
 984	data = kmap_local_page(sg_page(sg));
 985	data_offset = data + sg->offset;
 986
 987	/* Cannot modify original bio, copy to sg_out and apply Elephant to it */
 988	if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
 989		sg2 = crypt_get_sg_data(cc, dmreq->sg_in);
 990		data2 = kmap_local_page(sg_page(sg2));
 991		memcpy(data_offset, data2 + sg2->offset, cc->sector_size);
 992		kunmap_local(data2);
 993	}
 994
 995	if (bio_data_dir(dmreq->ctx->bio_in) != WRITE) {
 996		diffuser_disk_to_cpu((u32 *)data_offset, cc->sector_size / sizeof(u32));
 997		diffuser_b_decrypt((u32 *)data_offset, cc->sector_size / sizeof(u32));
 998		diffuser_a_decrypt((u32 *)data_offset, cc->sector_size / sizeof(u32));
 999		diffuser_cpu_to_disk((__le32 *)data_offset, cc->sector_size / sizeof(u32));
1000	}
1001
1002	for (i = 0; i < (cc->sector_size / 32); i++)
1003		crypto_xor(data_offset + i * 32, ks, 32);
1004
1005	if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
1006		diffuser_disk_to_cpu((u32 *)data_offset, cc->sector_size / sizeof(u32));
1007		diffuser_a_encrypt((u32 *)data_offset, cc->sector_size / sizeof(u32));
1008		diffuser_b_encrypt((u32 *)data_offset, cc->sector_size / sizeof(u32));
1009		diffuser_cpu_to_disk((__le32 *)data_offset, cc->sector_size / sizeof(u32));
1010	}
1011
1012	kunmap_local(data);
1013out:
1014	kfree_sensitive(ks);
1015	kfree_sensitive(es);
1016	skcipher_request_free(req);
1017	return r;
1018}
1019
1020static int crypt_iv_elephant_gen(struct crypt_config *cc, u8 *iv,
1021			    struct dm_crypt_request *dmreq)
1022{
1023	int r;
1024
1025	if (bio_data_dir(dmreq->ctx->bio_in) == WRITE) {
1026		r = crypt_iv_elephant(cc, dmreq);
1027		if (r)
1028			return r;
1029	}
1030
1031	return crypt_iv_eboiv_gen(cc, iv, dmreq);
1032}
1033
1034static int crypt_iv_elephant_post(struct crypt_config *cc, u8 *iv,
1035				  struct dm_crypt_request *dmreq)
1036{
1037	if (bio_data_dir(dmreq->ctx->bio_in) != WRITE)
1038		return crypt_iv_elephant(cc, dmreq);
1039
1040	return 0;
1041}
1042
1043static int crypt_iv_elephant_init(struct crypt_config *cc)
1044{
1045	struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
1046	int key_offset = cc->key_size - cc->key_extra_size;
1047
1048	return crypto_skcipher_setkey(elephant->tfm, &cc->key[key_offset], cc->key_extra_size);
1049}
1050
1051static int crypt_iv_elephant_wipe(struct crypt_config *cc)
1052{
1053	struct iv_elephant_private *elephant = &cc->iv_gen_private.elephant;
1054	u8 key[ELEPHANT_MAX_KEY_SIZE];
1055
1056	memset(key, 0, cc->key_extra_size);
1057	return crypto_skcipher_setkey(elephant->tfm, key, cc->key_extra_size);
1058}
1059
1060static const struct crypt_iv_operations crypt_iv_plain_ops = {
1061	.generator = crypt_iv_plain_gen
1062};
1063
1064static const struct crypt_iv_operations crypt_iv_plain64_ops = {
1065	.generator = crypt_iv_plain64_gen
1066};
1067
1068static const struct crypt_iv_operations crypt_iv_plain64be_ops = {
1069	.generator = crypt_iv_plain64be_gen
1070};
1071
1072static const struct crypt_iv_operations crypt_iv_essiv_ops = {
1073	.generator = crypt_iv_essiv_gen
1074};
1075
1076static const struct crypt_iv_operations crypt_iv_benbi_ops = {
1077	.ctr	   = crypt_iv_benbi_ctr,
1078	.dtr	   = crypt_iv_benbi_dtr,
1079	.generator = crypt_iv_benbi_gen
1080};
1081
1082static const struct crypt_iv_operations crypt_iv_null_ops = {
1083	.generator = crypt_iv_null_gen
1084};
1085
1086static const struct crypt_iv_operations crypt_iv_lmk_ops = {
1087	.ctr	   = crypt_iv_lmk_ctr,
1088	.dtr	   = crypt_iv_lmk_dtr,
1089	.init	   = crypt_iv_lmk_init,
1090	.wipe	   = crypt_iv_lmk_wipe,
1091	.generator = crypt_iv_lmk_gen,
1092	.post	   = crypt_iv_lmk_post
1093};
1094
1095static const struct crypt_iv_operations crypt_iv_tcw_ops = {
1096	.ctr	   = crypt_iv_tcw_ctr,
1097	.dtr	   = crypt_iv_tcw_dtr,
1098	.init	   = crypt_iv_tcw_init,
1099	.wipe	   = crypt_iv_tcw_wipe,
1100	.generator = crypt_iv_tcw_gen,
1101	.post	   = crypt_iv_tcw_post
1102};
1103
1104static const struct crypt_iv_operations crypt_iv_random_ops = {
1105	.generator = crypt_iv_random_gen
1106};
1107
1108static const struct crypt_iv_operations crypt_iv_eboiv_ops = {
1109	.ctr	   = crypt_iv_eboiv_ctr,
1110	.generator = crypt_iv_eboiv_gen
1111};
1112
1113static const struct crypt_iv_operations crypt_iv_elephant_ops = {
1114	.ctr	   = crypt_iv_elephant_ctr,
1115	.dtr	   = crypt_iv_elephant_dtr,
1116	.init	   = crypt_iv_elephant_init,
1117	.wipe	   = crypt_iv_elephant_wipe,
1118	.generator = crypt_iv_elephant_gen,
1119	.post	   = crypt_iv_elephant_post
1120};
1121
1122/*
1123 * Integrity extensions
1124 */
1125static bool crypt_integrity_aead(struct crypt_config *cc)
1126{
1127	return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags);
1128}
1129
1130static bool crypt_integrity_hmac(struct crypt_config *cc)
1131{
1132	return crypt_integrity_aead(cc) && cc->key_mac_size;
1133}
1134
1135/* Get sg containing data */
1136static struct scatterlist *crypt_get_sg_data(struct crypt_config *cc,
1137					     struct scatterlist *sg)
1138{
1139	if (unlikely(crypt_integrity_aead(cc)))
1140		return &sg[2];
1141
1142	return sg;
1143}
1144
1145static int dm_crypt_integrity_io_alloc(struct dm_crypt_io *io, struct bio *bio)
1146{
1147	struct bio_integrity_payload *bip;
1148	unsigned int tag_len;
1149	int ret;
1150
1151	if (!bio_sectors(bio) || !io->cc->on_disk_tag_size)
1152		return 0;
1153
1154	bip = bio_integrity_alloc(bio, GFP_NOIO, 1);
1155	if (IS_ERR(bip))
1156		return PTR_ERR(bip);
1157
1158	tag_len = io->cc->on_disk_tag_size * (bio_sectors(bio) >> io->cc->sector_shift);
1159
 
1160	bip->bip_iter.bi_sector = io->cc->start + io->sector;
1161
1162	ret = bio_integrity_add_page(bio, virt_to_page(io->integrity_metadata),
1163				     tag_len, offset_in_page(io->integrity_metadata));
1164	if (unlikely(ret != tag_len))
1165		return -ENOMEM;
1166
1167	return 0;
1168}
1169
1170static int crypt_integrity_ctr(struct crypt_config *cc, struct dm_target *ti)
1171{
1172#ifdef CONFIG_BLK_DEV_INTEGRITY
1173	struct blk_integrity *bi = blk_get_integrity(cc->dev->bdev->bd_disk);
1174	struct mapped_device *md = dm_table_get_md(ti->table);
1175
1176	/* From now we require underlying device with our integrity profile */
1177	if (!bi || strcasecmp(bi->profile->name, "DM-DIF-EXT-TAG")) {
1178		ti->error = "Integrity profile not supported.";
1179		return -EINVAL;
1180	}
1181
1182	if (bi->tag_size != cc->on_disk_tag_size ||
1183	    bi->tuple_size != cc->on_disk_tag_size) {
1184		ti->error = "Integrity profile tag size mismatch.";
1185		return -EINVAL;
1186	}
1187	if (1 << bi->interval_exp != cc->sector_size) {
1188		ti->error = "Integrity profile sector size mismatch.";
1189		return -EINVAL;
1190	}
1191
1192	if (crypt_integrity_aead(cc)) {
1193		cc->integrity_tag_size = cc->on_disk_tag_size - cc->integrity_iv_size;
1194		DMDEBUG("%s: Integrity AEAD, tag size %u, IV size %u.", dm_device_name(md),
1195		       cc->integrity_tag_size, cc->integrity_iv_size);
1196
1197		if (crypto_aead_setauthsize(any_tfm_aead(cc), cc->integrity_tag_size)) {
1198			ti->error = "Integrity AEAD auth tag size is not supported.";
1199			return -EINVAL;
1200		}
1201	} else if (cc->integrity_iv_size)
1202		DMDEBUG("%s: Additional per-sector space %u bytes for IV.", dm_device_name(md),
1203		       cc->integrity_iv_size);
1204
1205	if ((cc->integrity_tag_size + cc->integrity_iv_size) != bi->tag_size) {
1206		ti->error = "Not enough space for integrity tag in the profile.";
1207		return -EINVAL;
1208	}
1209
1210	return 0;
1211#else
1212	ti->error = "Integrity profile not supported.";
1213	return -EINVAL;
1214#endif
1215}
1216
1217static void crypt_convert_init(struct crypt_config *cc,
1218			       struct convert_context *ctx,
1219			       struct bio *bio_out, struct bio *bio_in,
1220			       sector_t sector)
1221{
1222	ctx->bio_in = bio_in;
1223	ctx->bio_out = bio_out;
1224	if (bio_in)
1225		ctx->iter_in = bio_in->bi_iter;
1226	if (bio_out)
1227		ctx->iter_out = bio_out->bi_iter;
1228	ctx->cc_sector = sector + cc->iv_offset;
1229	init_completion(&ctx->restart);
1230}
1231
1232static struct dm_crypt_request *dmreq_of_req(struct crypt_config *cc,
1233					     void *req)
1234{
1235	return (struct dm_crypt_request *)((char *)req + cc->dmreq_start);
1236}
1237
1238static void *req_of_dmreq(struct crypt_config *cc, struct dm_crypt_request *dmreq)
1239{
1240	return (void *)((char *)dmreq - cc->dmreq_start);
1241}
1242
1243static u8 *iv_of_dmreq(struct crypt_config *cc,
1244		       struct dm_crypt_request *dmreq)
1245{
1246	if (crypt_integrity_aead(cc))
1247		return (u8 *)ALIGN((unsigned long)(dmreq + 1),
1248			crypto_aead_alignmask(any_tfm_aead(cc)) + 1);
1249	else
1250		return (u8 *)ALIGN((unsigned long)(dmreq + 1),
1251			crypto_skcipher_alignmask(any_tfm(cc)) + 1);
1252}
1253
1254static u8 *org_iv_of_dmreq(struct crypt_config *cc,
1255		       struct dm_crypt_request *dmreq)
1256{
1257	return iv_of_dmreq(cc, dmreq) + cc->iv_size;
1258}
1259
1260static __le64 *org_sector_of_dmreq(struct crypt_config *cc,
1261		       struct dm_crypt_request *dmreq)
1262{
1263	u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size + cc->iv_size;
1264
1265	return (__le64 *) ptr;
1266}
1267
1268static unsigned int *org_tag_of_dmreq(struct crypt_config *cc,
1269		       struct dm_crypt_request *dmreq)
1270{
1271	u8 *ptr = iv_of_dmreq(cc, dmreq) + cc->iv_size +
1272		  cc->iv_size + sizeof(uint64_t);
1273
1274	return (unsigned int *)ptr;
1275}
1276
1277static void *tag_from_dmreq(struct crypt_config *cc,
1278				struct dm_crypt_request *dmreq)
1279{
1280	struct convert_context *ctx = dmreq->ctx;
1281	struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
1282
1283	return &io->integrity_metadata[*org_tag_of_dmreq(cc, dmreq) *
1284		cc->on_disk_tag_size];
1285}
1286
1287static void *iv_tag_from_dmreq(struct crypt_config *cc,
1288			       struct dm_crypt_request *dmreq)
1289{
1290	return tag_from_dmreq(cc, dmreq) + cc->integrity_tag_size;
1291}
1292
1293static int crypt_convert_block_aead(struct crypt_config *cc,
1294				     struct convert_context *ctx,
1295				     struct aead_request *req,
1296				     unsigned int tag_offset)
1297{
1298	struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in);
1299	struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out);
1300	struct dm_crypt_request *dmreq;
1301	u8 *iv, *org_iv, *tag_iv, *tag;
1302	__le64 *sector;
1303	int r = 0;
1304
1305	BUG_ON(cc->integrity_iv_size && cc->integrity_iv_size != cc->iv_size);
1306
1307	/* Reject unexpected unaligned bio. */
1308	if (unlikely(bv_in.bv_len & (cc->sector_size - 1)))
1309		return -EIO;
1310
1311	dmreq = dmreq_of_req(cc, req);
1312	dmreq->iv_sector = ctx->cc_sector;
1313	if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
1314		dmreq->iv_sector >>= cc->sector_shift;
1315	dmreq->ctx = ctx;
1316
1317	*org_tag_of_dmreq(cc, dmreq) = tag_offset;
1318
1319	sector = org_sector_of_dmreq(cc, dmreq);
1320	*sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset);
1321
1322	iv = iv_of_dmreq(cc, dmreq);
1323	org_iv = org_iv_of_dmreq(cc, dmreq);
1324	tag = tag_from_dmreq(cc, dmreq);
1325	tag_iv = iv_tag_from_dmreq(cc, dmreq);
1326
1327	/* AEAD request:
1328	 *  |----- AAD -------|------ DATA -------|-- AUTH TAG --|
1329	 *  | (authenticated) | (auth+encryption) |              |
1330	 *  | sector_LE |  IV |  sector in/out    |  tag in/out  |
1331	 */
1332	sg_init_table(dmreq->sg_in, 4);
1333	sg_set_buf(&dmreq->sg_in[0], sector, sizeof(uint64_t));
1334	sg_set_buf(&dmreq->sg_in[1], org_iv, cc->iv_size);
1335	sg_set_page(&dmreq->sg_in[2], bv_in.bv_page, cc->sector_size, bv_in.bv_offset);
1336	sg_set_buf(&dmreq->sg_in[3], tag, cc->integrity_tag_size);
1337
1338	sg_init_table(dmreq->sg_out, 4);
1339	sg_set_buf(&dmreq->sg_out[0], sector, sizeof(uint64_t));
1340	sg_set_buf(&dmreq->sg_out[1], org_iv, cc->iv_size);
1341	sg_set_page(&dmreq->sg_out[2], bv_out.bv_page, cc->sector_size, bv_out.bv_offset);
1342	sg_set_buf(&dmreq->sg_out[3], tag, cc->integrity_tag_size);
1343
1344	if (cc->iv_gen_ops) {
1345		/* For READs use IV stored in integrity metadata */
1346		if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) {
1347			memcpy(org_iv, tag_iv, cc->iv_size);
1348		} else {
1349			r = cc->iv_gen_ops->generator(cc, org_iv, dmreq);
1350			if (r < 0)
1351				return r;
1352			/* Store generated IV in integrity metadata */
1353			if (cc->integrity_iv_size)
1354				memcpy(tag_iv, org_iv, cc->iv_size);
1355		}
1356		/* Working copy of IV, to be modified in crypto API */
1357		memcpy(iv, org_iv, cc->iv_size);
1358	}
1359
1360	aead_request_set_ad(req, sizeof(uint64_t) + cc->iv_size);
1361	if (bio_data_dir(ctx->bio_in) == WRITE) {
1362		aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out,
1363				       cc->sector_size, iv);
1364		r = crypto_aead_encrypt(req);
1365		if (cc->integrity_tag_size + cc->integrity_iv_size != cc->on_disk_tag_size)
1366			memset(tag + cc->integrity_tag_size + cc->integrity_iv_size, 0,
1367			       cc->on_disk_tag_size - (cc->integrity_tag_size + cc->integrity_iv_size));
1368	} else {
1369		aead_request_set_crypt(req, dmreq->sg_in, dmreq->sg_out,
1370				       cc->sector_size + cc->integrity_tag_size, iv);
1371		r = crypto_aead_decrypt(req);
1372	}
1373
1374	if (r == -EBADMSG) {
1375		sector_t s = le64_to_cpu(*sector);
1376
1377		ctx->aead_failed = true;
1378		if (ctx->aead_recheck) {
1379			DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu",
1380				    ctx->bio_in->bi_bdev, s);
1381			dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead",
1382					 ctx->bio_in, s, 0);
1383		}
1384	}
1385
1386	if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
1387		r = cc->iv_gen_ops->post(cc, org_iv, dmreq);
1388
1389	bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size);
1390	bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size);
1391
1392	return r;
1393}
1394
1395static int crypt_convert_block_skcipher(struct crypt_config *cc,
1396					struct convert_context *ctx,
1397					struct skcipher_request *req,
1398					unsigned int tag_offset)
1399{
1400	struct bio_vec bv_in = bio_iter_iovec(ctx->bio_in, ctx->iter_in);
1401	struct bio_vec bv_out = bio_iter_iovec(ctx->bio_out, ctx->iter_out);
1402	struct scatterlist *sg_in, *sg_out;
1403	struct dm_crypt_request *dmreq;
1404	u8 *iv, *org_iv, *tag_iv;
1405	__le64 *sector;
1406	int r = 0;
1407
1408	/* Reject unexpected unaligned bio. */
1409	if (unlikely(bv_in.bv_len & (cc->sector_size - 1)))
1410		return -EIO;
1411
1412	dmreq = dmreq_of_req(cc, req);
1413	dmreq->iv_sector = ctx->cc_sector;
1414	if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
1415		dmreq->iv_sector >>= cc->sector_shift;
1416	dmreq->ctx = ctx;
1417
1418	*org_tag_of_dmreq(cc, dmreq) = tag_offset;
1419
1420	iv = iv_of_dmreq(cc, dmreq);
1421	org_iv = org_iv_of_dmreq(cc, dmreq);
1422	tag_iv = iv_tag_from_dmreq(cc, dmreq);
1423
1424	sector = org_sector_of_dmreq(cc, dmreq);
1425	*sector = cpu_to_le64(ctx->cc_sector - cc->iv_offset);
1426
1427	/* For skcipher we use only the first sg item */
1428	sg_in  = &dmreq->sg_in[0];
1429	sg_out = &dmreq->sg_out[0];
1430
1431	sg_init_table(sg_in, 1);
1432	sg_set_page(sg_in, bv_in.bv_page, cc->sector_size, bv_in.bv_offset);
1433
1434	sg_init_table(sg_out, 1);
1435	sg_set_page(sg_out, bv_out.bv_page, cc->sector_size, bv_out.bv_offset);
1436
1437	if (cc->iv_gen_ops) {
1438		/* For READs use IV stored in integrity metadata */
1439		if (cc->integrity_iv_size && bio_data_dir(ctx->bio_in) != WRITE) {
1440			memcpy(org_iv, tag_iv, cc->integrity_iv_size);
1441		} else {
1442			r = cc->iv_gen_ops->generator(cc, org_iv, dmreq);
1443			if (r < 0)
1444				return r;
1445			/* Data can be already preprocessed in generator */
1446			if (test_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags))
1447				sg_in = sg_out;
1448			/* Store generated IV in integrity metadata */
1449			if (cc->integrity_iv_size)
1450				memcpy(tag_iv, org_iv, cc->integrity_iv_size);
1451		}
1452		/* Working copy of IV, to be modified in crypto API */
1453		memcpy(iv, org_iv, cc->iv_size);
1454	}
1455
1456	skcipher_request_set_crypt(req, sg_in, sg_out, cc->sector_size, iv);
1457
1458	if (bio_data_dir(ctx->bio_in) == WRITE)
1459		r = crypto_skcipher_encrypt(req);
1460	else
1461		r = crypto_skcipher_decrypt(req);
1462
1463	if (!r && cc->iv_gen_ops && cc->iv_gen_ops->post)
1464		r = cc->iv_gen_ops->post(cc, org_iv, dmreq);
1465
1466	bio_advance_iter(ctx->bio_in, &ctx->iter_in, cc->sector_size);
1467	bio_advance_iter(ctx->bio_out, &ctx->iter_out, cc->sector_size);
1468
1469	return r;
1470}
1471
1472static void kcryptd_async_done(void *async_req, int error);
 
1473
1474static int crypt_alloc_req_skcipher(struct crypt_config *cc,
1475				     struct convert_context *ctx)
1476{
1477	unsigned int key_index = ctx->cc_sector & (cc->tfms_count - 1);
1478
1479	if (!ctx->r.req) {
1480		ctx->r.req = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO);
1481		if (!ctx->r.req)
1482			return -ENOMEM;
1483	}
1484
1485	skcipher_request_set_tfm(ctx->r.req, cc->cipher_tfm.tfms[key_index]);
1486
1487	/*
1488	 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs
1489	 * requests if driver request queue is full.
1490	 */
1491	skcipher_request_set_callback(ctx->r.req,
1492	    CRYPTO_TFM_REQ_MAY_BACKLOG,
1493	    kcryptd_async_done, dmreq_of_req(cc, ctx->r.req));
1494
1495	return 0;
1496}
1497
1498static int crypt_alloc_req_aead(struct crypt_config *cc,
1499				 struct convert_context *ctx)
1500{
1501	if (!ctx->r.req_aead) {
1502		ctx->r.req_aead = mempool_alloc(&cc->req_pool, in_interrupt() ? GFP_ATOMIC : GFP_NOIO);
1503		if (!ctx->r.req_aead)
1504			return -ENOMEM;
1505	}
1506
1507	aead_request_set_tfm(ctx->r.req_aead, cc->cipher_tfm.tfms_aead[0]);
1508
1509	/*
1510	 * Use REQ_MAY_BACKLOG so a cipher driver internally backlogs
1511	 * requests if driver request queue is full.
1512	 */
1513	aead_request_set_callback(ctx->r.req_aead,
1514	    CRYPTO_TFM_REQ_MAY_BACKLOG,
1515	    kcryptd_async_done, dmreq_of_req(cc, ctx->r.req_aead));
1516
1517	return 0;
1518}
1519
1520static int crypt_alloc_req(struct crypt_config *cc,
1521			    struct convert_context *ctx)
1522{
1523	if (crypt_integrity_aead(cc))
1524		return crypt_alloc_req_aead(cc, ctx);
1525	else
1526		return crypt_alloc_req_skcipher(cc, ctx);
1527}
1528
1529static void crypt_free_req_skcipher(struct crypt_config *cc,
1530				    struct skcipher_request *req, struct bio *base_bio)
1531{
1532	struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size);
1533
1534	if ((struct skcipher_request *)(io + 1) != req)
1535		mempool_free(req, &cc->req_pool);
1536}
1537
1538static void crypt_free_req_aead(struct crypt_config *cc,
1539				struct aead_request *req, struct bio *base_bio)
1540{
1541	struct dm_crypt_io *io = dm_per_bio_data(base_bio, cc->per_bio_data_size);
1542
1543	if ((struct aead_request *)(io + 1) != req)
1544		mempool_free(req, &cc->req_pool);
1545}
1546
1547static void crypt_free_req(struct crypt_config *cc, void *req, struct bio *base_bio)
1548{
1549	if (crypt_integrity_aead(cc))
1550		crypt_free_req_aead(cc, req, base_bio);
1551	else
1552		crypt_free_req_skcipher(cc, req, base_bio);
1553}
1554
1555/*
1556 * Encrypt / decrypt data from one bio to another one (can be the same one)
1557 */
1558static blk_status_t crypt_convert(struct crypt_config *cc,
1559			 struct convert_context *ctx, bool atomic, bool reset_pending)
1560{
1561	unsigned int tag_offset = 0;
1562	unsigned int sector_step = cc->sector_size >> SECTOR_SHIFT;
1563	int r;
1564
1565	/*
1566	 * if reset_pending is set we are dealing with the bio for the first time,
1567	 * else we're continuing to work on the previous bio, so don't mess with
1568	 * the cc_pending counter
1569	 */
1570	if (reset_pending)
1571		atomic_set(&ctx->cc_pending, 1);
1572
1573	while (ctx->iter_in.bi_size && ctx->iter_out.bi_size) {
1574
1575		r = crypt_alloc_req(cc, ctx);
1576		if (r) {
1577			complete(&ctx->restart);
1578			return BLK_STS_DEV_RESOURCE;
1579		}
1580
1581		atomic_inc(&ctx->cc_pending);
1582
1583		if (crypt_integrity_aead(cc))
1584			r = crypt_convert_block_aead(cc, ctx, ctx->r.req_aead, tag_offset);
1585		else
1586			r = crypt_convert_block_skcipher(cc, ctx, ctx->r.req, tag_offset);
1587
1588		switch (r) {
1589		/*
1590		 * The request was queued by a crypto driver
1591		 * but the driver request queue is full, let's wait.
1592		 */
1593		case -EBUSY:
1594			if (in_interrupt()) {
1595				if (try_wait_for_completion(&ctx->restart)) {
1596					/*
1597					 * we don't have to block to wait for completion,
1598					 * so proceed
1599					 */
1600				} else {
1601					/*
1602					 * we can't wait for completion without blocking
1603					 * exit and continue processing in a workqueue
1604					 */
1605					ctx->r.req = NULL;
1606					ctx->cc_sector += sector_step;
1607					tag_offset++;
1608					return BLK_STS_DEV_RESOURCE;
1609				}
1610			} else {
1611				wait_for_completion(&ctx->restart);
1612			}
1613			reinit_completion(&ctx->restart);
1614			fallthrough;
1615		/*
1616		 * The request is queued and processed asynchronously,
1617		 * completion function kcryptd_async_done() will be called.
1618		 */
1619		case -EINPROGRESS:
1620			ctx->r.req = NULL;
1621			ctx->cc_sector += sector_step;
1622			tag_offset++;
1623			continue;
1624		/*
1625		 * The request was already processed (synchronously).
1626		 */
1627		case 0:
1628			atomic_dec(&ctx->cc_pending);
1629			ctx->cc_sector += sector_step;
1630			tag_offset++;
1631			if (!atomic)
1632				cond_resched();
1633			continue;
1634		/*
1635		 * There was a data integrity error.
1636		 */
1637		case -EBADMSG:
1638			atomic_dec(&ctx->cc_pending);
1639			return BLK_STS_PROTECTION;
1640		/*
1641		 * There was an error while processing the request.
1642		 */
1643		default:
1644			atomic_dec(&ctx->cc_pending);
1645			return BLK_STS_IOERR;
1646		}
1647	}
1648
1649	return 0;
1650}
1651
1652static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone);
1653
1654/*
1655 * Generate a new unfragmented bio with the given size
1656 * This should never violate the device limitations (but only because
1657 * max_segment_size is being constrained to PAGE_SIZE).
1658 *
1659 * This function may be called concurrently. If we allocate from the mempool
1660 * concurrently, there is a possibility of deadlock. For example, if we have
1661 * mempool of 256 pages, two processes, each wanting 256, pages allocate from
1662 * the mempool concurrently, it may deadlock in a situation where both processes
1663 * have allocated 128 pages and the mempool is exhausted.
1664 *
1665 * In order to avoid this scenario we allocate the pages under a mutex.
1666 *
1667 * In order to not degrade performance with excessive locking, we try
1668 * non-blocking allocations without a mutex first but on failure we fallback
1669 * to blocking allocations with a mutex.
1670 *
1671 * In order to reduce allocation overhead, we try to allocate compound pages in
1672 * the first pass. If they are not available, we fall back to the mempool.
1673 */
1674static struct bio *crypt_alloc_buffer(struct dm_crypt_io *io, unsigned int size)
1675{
1676	struct crypt_config *cc = io->cc;
1677	struct bio *clone;
1678	unsigned int nr_iovecs = (size + PAGE_SIZE - 1) >> PAGE_SHIFT;
1679	gfp_t gfp_mask = GFP_NOWAIT | __GFP_HIGHMEM;
1680	unsigned int remaining_size;
1681	unsigned int order = MAX_PAGE_ORDER;
1682
1683retry:
1684	if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM))
1685		mutex_lock(&cc->bio_alloc_lock);
1686
1687	clone = bio_alloc_bioset(cc->dev->bdev, nr_iovecs, io->base_bio->bi_opf,
1688				 GFP_NOIO, &cc->bs);
1689	clone->bi_private = io;
1690	clone->bi_end_io = crypt_endio;
 
1691
1692	remaining_size = size;
1693
1694	while (remaining_size) {
1695		struct page *pages;
1696		unsigned size_to_add;
1697		unsigned remaining_order = __fls((remaining_size + PAGE_SIZE - 1) >> PAGE_SHIFT);
1698		order = min(order, remaining_order);
1699
1700		while (order > 0) {
1701			if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) +
1702					(1 << order) > dm_crypt_pages_per_client))
1703				goto decrease_order;
1704			pages = alloc_pages(gfp_mask
1705				| __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_NOWARN | __GFP_COMP,
1706				order);
1707			if (likely(pages != NULL)) {
1708				percpu_counter_add(&cc->n_allocated_pages, 1 << order);
1709				goto have_pages;
1710			}
1711decrease_order:
1712			order--;
1713		}
1714
1715		pages = mempool_alloc(&cc->page_pool, gfp_mask);
1716		if (!pages) {
1717			crypt_free_buffer_pages(cc, clone);
1718			bio_put(clone);
1719			gfp_mask |= __GFP_DIRECT_RECLAIM;
1720			order = 0;
1721			goto retry;
1722		}
1723
1724have_pages:
1725		size_to_add = min((unsigned)PAGE_SIZE << order, remaining_size);
1726		__bio_add_page(clone, pages, size_to_add, 0);
1727		remaining_size -= size_to_add;
 
1728	}
1729
1730	/* Allocate space for integrity tags */
1731	if (dm_crypt_integrity_io_alloc(io, clone)) {
1732		crypt_free_buffer_pages(cc, clone);
1733		bio_put(clone);
1734		clone = NULL;
1735	}
1736
1737	if (unlikely(gfp_mask & __GFP_DIRECT_RECLAIM))
1738		mutex_unlock(&cc->bio_alloc_lock);
1739
1740	return clone;
1741}
1742
1743static void crypt_free_buffer_pages(struct crypt_config *cc, struct bio *clone)
1744{
1745	struct folio_iter fi;
 
1746
1747	if (clone->bi_vcnt > 0) { /* bio_for_each_folio_all crashes with an empty bio */
1748		bio_for_each_folio_all(fi, clone) {
1749			if (folio_test_large(fi.folio)) {
1750				percpu_counter_sub(&cc->n_allocated_pages,
1751						1 << folio_order(fi.folio));
1752				folio_put(fi.folio);
1753			} else {
1754				mempool_free(&fi.folio->page, &cc->page_pool);
1755			}
1756		}
1757	}
1758}
1759
1760static void crypt_io_init(struct dm_crypt_io *io, struct crypt_config *cc,
1761			  struct bio *bio, sector_t sector)
1762{
1763	io->cc = cc;
1764	io->base_bio = bio;
1765	io->sector = sector;
1766	io->error = 0;
1767	io->ctx.aead_recheck = false;
1768	io->ctx.aead_failed = false;
1769	io->ctx.r.req = NULL;
1770	io->integrity_metadata = NULL;
1771	io->integrity_metadata_from_pool = false;
1772	atomic_set(&io->io_pending, 0);
1773}
1774
1775static void crypt_inc_pending(struct dm_crypt_io *io)
1776{
1777	atomic_inc(&io->io_pending);
1778}
1779
1780static void kcryptd_queue_read(struct dm_crypt_io *io);
1781
1782/*
1783 * One of the bios was finished. Check for completion of
1784 * the whole request and correctly clean up the buffer.
1785 */
1786static void crypt_dec_pending(struct dm_crypt_io *io)
1787{
1788	struct crypt_config *cc = io->cc;
1789	struct bio *base_bio = io->base_bio;
1790	blk_status_t error = io->error;
1791
1792	if (!atomic_dec_and_test(&io->io_pending))
1793		return;
1794
1795	if (likely(!io->ctx.aead_recheck) && unlikely(io->ctx.aead_failed) &&
1796	    cc->on_disk_tag_size && bio_data_dir(base_bio) == READ) {
1797		io->ctx.aead_recheck = true;
1798		io->ctx.aead_failed = false;
1799		io->error = 0;
1800		kcryptd_queue_read(io);
1801		return;
1802	}
1803
1804	if (io->ctx.r.req)
1805		crypt_free_req(cc, io->ctx.r.req, base_bio);
1806
1807	if (unlikely(io->integrity_metadata_from_pool))
1808		mempool_free(io->integrity_metadata, &io->cc->tag_pool);
1809	else
1810		kfree(io->integrity_metadata);
1811
1812	base_bio->bi_status = error;
1813
1814	bio_endio(base_bio);
1815}
1816
1817/*
1818 * kcryptd/kcryptd_io:
1819 *
1820 * Needed because it would be very unwise to do decryption in an
1821 * interrupt context.
1822 *
1823 * kcryptd performs the actual encryption or decryption.
1824 *
1825 * kcryptd_io performs the IO submission.
1826 *
1827 * They must be separated as otherwise the final stages could be
1828 * starved by new requests which can block in the first stages due
1829 * to memory allocation.
1830 *
1831 * The work is done per CPU global for all dm-crypt instances.
1832 * They should not depend on each other and do not block.
1833 */
1834static void crypt_endio(struct bio *clone)
1835{
1836	struct dm_crypt_io *io = clone->bi_private;
1837	struct crypt_config *cc = io->cc;
1838	unsigned int rw = bio_data_dir(clone);
1839	blk_status_t error = clone->bi_status;
1840
1841	if (io->ctx.aead_recheck && !error) {
1842		kcryptd_queue_crypt(io);
1843		return;
1844	}
1845
1846	/*
1847	 * free the processed pages
1848	 */
1849	if (rw == WRITE || io->ctx.aead_recheck)
1850		crypt_free_buffer_pages(cc, clone);
1851
 
1852	bio_put(clone);
1853
1854	if (rw == READ && !error) {
1855		kcryptd_queue_crypt(io);
1856		return;
1857	}
1858
1859	if (unlikely(error))
1860		io->error = error;
1861
1862	crypt_dec_pending(io);
1863}
1864
1865#define CRYPT_MAP_READ_GFP GFP_NOWAIT
 
 
 
 
 
 
 
 
1866
1867static int kcryptd_io_read(struct dm_crypt_io *io, gfp_t gfp)
1868{
1869	struct crypt_config *cc = io->cc;
1870	struct bio *clone;
1871
1872	if (io->ctx.aead_recheck) {
1873		if (!(gfp & __GFP_DIRECT_RECLAIM))
1874			return 1;
1875		crypt_inc_pending(io);
1876		clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size);
1877		if (unlikely(!clone)) {
1878			crypt_dec_pending(io);
1879			return 1;
1880		}
1881		clone->bi_iter.bi_sector = cc->start + io->sector;
1882		crypt_convert_init(cc, &io->ctx, clone, clone, io->sector);
1883		io->saved_bi_iter = clone->bi_iter;
1884		dm_submit_bio_remap(io->base_bio, clone);
1885		return 0;
1886	}
1887
1888	/*
1889	 * We need the original biovec array in order to decrypt the whole bio
1890	 * data *afterwards* -- thanks to immutable biovecs we don't need to
1891	 * worry about the block layer modifying the biovec array; so leverage
1892	 * bio_alloc_clone().
1893	 */
1894	clone = bio_alloc_clone(cc->dev->bdev, io->base_bio, gfp, &cc->bs);
1895	if (!clone)
1896		return 1;
1897	clone->bi_private = io;
1898	clone->bi_end_io = crypt_endio;
1899
1900	crypt_inc_pending(io);
1901
 
1902	clone->bi_iter.bi_sector = cc->start + io->sector;
1903
1904	if (dm_crypt_integrity_io_alloc(io, clone)) {
1905		crypt_dec_pending(io);
1906		bio_put(clone);
1907		return 1;
1908	}
1909
1910	dm_submit_bio_remap(io->base_bio, clone);
1911	return 0;
1912}
1913
1914static void kcryptd_io_read_work(struct work_struct *work)
1915{
1916	struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
1917
1918	crypt_inc_pending(io);
1919	if (kcryptd_io_read(io, GFP_NOIO))
1920		io->error = BLK_STS_RESOURCE;
1921	crypt_dec_pending(io);
1922}
1923
1924static void kcryptd_queue_read(struct dm_crypt_io *io)
1925{
1926	struct crypt_config *cc = io->cc;
1927
1928	INIT_WORK(&io->work, kcryptd_io_read_work);
1929	queue_work(cc->io_queue, &io->work);
1930}
1931
1932static void kcryptd_io_write(struct dm_crypt_io *io)
1933{
1934	struct bio *clone = io->ctx.bio_out;
1935
1936	dm_submit_bio_remap(io->base_bio, clone);
1937}
1938
1939#define crypt_io_from_node(node) rb_entry((node), struct dm_crypt_io, rb_node)
1940
1941static int dmcrypt_write(void *data)
1942{
1943	struct crypt_config *cc = data;
1944	struct dm_crypt_io *io;
1945
1946	while (1) {
1947		struct rb_root write_tree;
1948		struct blk_plug plug;
1949
1950		spin_lock_irq(&cc->write_thread_lock);
1951continue_locked:
1952
1953		if (!RB_EMPTY_ROOT(&cc->write_tree))
1954			goto pop_from_list;
1955
1956		set_current_state(TASK_INTERRUPTIBLE);
1957
1958		spin_unlock_irq(&cc->write_thread_lock);
1959
1960		if (unlikely(kthread_should_stop())) {
1961			set_current_state(TASK_RUNNING);
1962			break;
1963		}
1964
1965		schedule();
1966
1967		set_current_state(TASK_RUNNING);
1968		spin_lock_irq(&cc->write_thread_lock);
1969		goto continue_locked;
1970
1971pop_from_list:
1972		write_tree = cc->write_tree;
1973		cc->write_tree = RB_ROOT;
1974		spin_unlock_irq(&cc->write_thread_lock);
1975
1976		BUG_ON(rb_parent(write_tree.rb_node));
1977
1978		/*
1979		 * Note: we cannot walk the tree here with rb_next because
1980		 * the structures may be freed when kcryptd_io_write is called.
1981		 */
1982		blk_start_plug(&plug);
1983		do {
1984			io = crypt_io_from_node(rb_first(&write_tree));
1985			rb_erase(&io->rb_node, &write_tree);
1986			kcryptd_io_write(io);
1987			cond_resched();
1988		} while (!RB_EMPTY_ROOT(&write_tree));
1989		blk_finish_plug(&plug);
1990	}
1991	return 0;
1992}
1993
1994static void kcryptd_crypt_write_io_submit(struct dm_crypt_io *io, int async)
1995{
1996	struct bio *clone = io->ctx.bio_out;
1997	struct crypt_config *cc = io->cc;
1998	unsigned long flags;
1999	sector_t sector;
2000	struct rb_node **rbp, *parent;
2001
2002	if (unlikely(io->error)) {
2003		crypt_free_buffer_pages(cc, clone);
2004		bio_put(clone);
2005		crypt_dec_pending(io);
2006		return;
2007	}
2008
2009	/* crypt_convert should have filled the clone bio */
2010	BUG_ON(io->ctx.iter_out.bi_size);
2011
2012	clone->bi_iter.bi_sector = cc->start + io->sector;
2013
2014	if ((likely(!async) && test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags)) ||
2015	    test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags)) {
2016		dm_submit_bio_remap(io->base_bio, clone);
2017		return;
2018	}
2019
2020	spin_lock_irqsave(&cc->write_thread_lock, flags);
2021	if (RB_EMPTY_ROOT(&cc->write_tree))
2022		wake_up_process(cc->write_thread);
2023	rbp = &cc->write_tree.rb_node;
2024	parent = NULL;
2025	sector = io->sector;
2026	while (*rbp) {
2027		parent = *rbp;
2028		if (sector < crypt_io_from_node(parent)->sector)
2029			rbp = &(*rbp)->rb_left;
2030		else
2031			rbp = &(*rbp)->rb_right;
2032	}
2033	rb_link_node(&io->rb_node, parent, rbp);
2034	rb_insert_color(&io->rb_node, &cc->write_tree);
2035	spin_unlock_irqrestore(&cc->write_thread_lock, flags);
2036}
2037
2038static bool kcryptd_crypt_write_inline(struct crypt_config *cc,
2039				       struct convert_context *ctx)
2040
2041{
2042	if (!test_bit(DM_CRYPT_WRITE_INLINE, &cc->flags))
2043		return false;
2044
2045	/*
2046	 * Note: zone append writes (REQ_OP_ZONE_APPEND) do not have ordering
2047	 * constraints so they do not need to be issued inline by
2048	 * kcryptd_crypt_write_convert().
2049	 */
2050	switch (bio_op(ctx->bio_in)) {
2051	case REQ_OP_WRITE:
 
2052	case REQ_OP_WRITE_ZEROES:
2053		return true;
2054	default:
2055		return false;
2056	}
2057}
2058
2059static void kcryptd_crypt_write_continue(struct work_struct *work)
2060{
2061	struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
2062	struct crypt_config *cc = io->cc;
2063	struct convert_context *ctx = &io->ctx;
2064	int crypt_finished;
2065	sector_t sector = io->sector;
2066	blk_status_t r;
2067
2068	wait_for_completion(&ctx->restart);
2069	reinit_completion(&ctx->restart);
2070
2071	r = crypt_convert(cc, &io->ctx, true, false);
2072	if (r)
2073		io->error = r;
2074	crypt_finished = atomic_dec_and_test(&ctx->cc_pending);
2075	if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) {
2076		/* Wait for completion signaled by kcryptd_async_done() */
2077		wait_for_completion(&ctx->restart);
2078		crypt_finished = 1;
2079	}
2080
2081	/* Encryption was already finished, submit io now */
2082	if (crypt_finished) {
2083		kcryptd_crypt_write_io_submit(io, 0);
2084		io->sector = sector;
2085	}
2086
2087	crypt_dec_pending(io);
2088}
2089
2090static void kcryptd_crypt_write_convert(struct dm_crypt_io *io)
2091{
2092	struct crypt_config *cc = io->cc;
2093	struct convert_context *ctx = &io->ctx;
2094	struct bio *clone;
2095	int crypt_finished;
2096	sector_t sector = io->sector;
2097	blk_status_t r;
2098
2099	/*
2100	 * Prevent io from disappearing until this function completes.
2101	 */
2102	crypt_inc_pending(io);
2103	crypt_convert_init(cc, ctx, NULL, io->base_bio, sector);
2104
2105	clone = crypt_alloc_buffer(io, io->base_bio->bi_iter.bi_size);
2106	if (unlikely(!clone)) {
2107		io->error = BLK_STS_IOERR;
2108		goto dec;
2109	}
2110
2111	io->ctx.bio_out = clone;
2112	io->ctx.iter_out = clone->bi_iter;
2113
2114	if (crypt_integrity_aead(cc)) {
2115		bio_copy_data(clone, io->base_bio);
2116		io->ctx.bio_in = clone;
2117		io->ctx.iter_in = clone->bi_iter;
2118	}
2119
2120	sector += bio_sectors(clone);
2121
2122	crypt_inc_pending(io);
2123	r = crypt_convert(cc, ctx,
2124			  test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags), true);
2125	/*
2126	 * Crypto API backlogged the request, because its queue was full
2127	 * and we're in softirq context, so continue from a workqueue
2128	 * (TODO: is it actually possible to be in softirq in the write path?)
2129	 */
2130	if (r == BLK_STS_DEV_RESOURCE) {
2131		INIT_WORK(&io->work, kcryptd_crypt_write_continue);
2132		queue_work(cc->crypt_queue, &io->work);
2133		return;
2134	}
2135	if (r)
2136		io->error = r;
2137	crypt_finished = atomic_dec_and_test(&ctx->cc_pending);
2138	if (!crypt_finished && kcryptd_crypt_write_inline(cc, ctx)) {
2139		/* Wait for completion signaled by kcryptd_async_done() */
2140		wait_for_completion(&ctx->restart);
2141		crypt_finished = 1;
2142	}
2143
2144	/* Encryption was already finished, submit io now */
2145	if (crypt_finished) {
2146		kcryptd_crypt_write_io_submit(io, 0);
2147		io->sector = sector;
2148	}
2149
2150dec:
2151	crypt_dec_pending(io);
2152}
2153
2154static void kcryptd_crypt_read_done(struct dm_crypt_io *io)
2155{
2156	if (io->ctx.aead_recheck) {
2157		if (!io->error) {
2158			io->ctx.bio_in->bi_iter = io->saved_bi_iter;
2159			bio_copy_data(io->base_bio, io->ctx.bio_in);
2160		}
2161		crypt_free_buffer_pages(io->cc, io->ctx.bio_in);
2162		bio_put(io->ctx.bio_in);
2163	}
2164	crypt_dec_pending(io);
2165}
2166
2167static void kcryptd_crypt_read_continue(struct work_struct *work)
2168{
2169	struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
2170	struct crypt_config *cc = io->cc;
2171	blk_status_t r;
2172
2173	wait_for_completion(&io->ctx.restart);
2174	reinit_completion(&io->ctx.restart);
2175
2176	r = crypt_convert(cc, &io->ctx, true, false);
2177	if (r)
2178		io->error = r;
2179
2180	if (atomic_dec_and_test(&io->ctx.cc_pending))
2181		kcryptd_crypt_read_done(io);
2182
2183	crypt_dec_pending(io);
2184}
2185
2186static void kcryptd_crypt_read_convert(struct dm_crypt_io *io)
2187{
2188	struct crypt_config *cc = io->cc;
2189	blk_status_t r;
2190
2191	crypt_inc_pending(io);
2192
2193	if (io->ctx.aead_recheck) {
2194		io->ctx.cc_sector = io->sector + cc->iv_offset;
2195		r = crypt_convert(cc, &io->ctx,
2196				  test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true);
2197	} else {
2198		crypt_convert_init(cc, &io->ctx, io->base_bio, io->base_bio,
2199				   io->sector);
2200
2201		r = crypt_convert(cc, &io->ctx,
2202				  test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags), true);
2203	}
2204	/*
2205	 * Crypto API backlogged the request, because its queue was full
2206	 * and we're in softirq context, so continue from a workqueue
2207	 */
2208	if (r == BLK_STS_DEV_RESOURCE) {
2209		INIT_WORK(&io->work, kcryptd_crypt_read_continue);
2210		queue_work(cc->crypt_queue, &io->work);
2211		return;
2212	}
2213	if (r)
2214		io->error = r;
2215
2216	if (atomic_dec_and_test(&io->ctx.cc_pending))
2217		kcryptd_crypt_read_done(io);
2218
2219	crypt_dec_pending(io);
2220}
2221
2222static void kcryptd_async_done(void *data, int error)
 
2223{
2224	struct dm_crypt_request *dmreq = data;
2225	struct convert_context *ctx = dmreq->ctx;
2226	struct dm_crypt_io *io = container_of(ctx, struct dm_crypt_io, ctx);
2227	struct crypt_config *cc = io->cc;
2228
2229	/*
2230	 * A request from crypto driver backlog is going to be processed now,
2231	 * finish the completion and continue in crypt_convert().
2232	 * (Callback will be called for the second time for this request.)
2233	 */
2234	if (error == -EINPROGRESS) {
2235		complete(&ctx->restart);
2236		return;
2237	}
2238
2239	if (!error && cc->iv_gen_ops && cc->iv_gen_ops->post)
2240		error = cc->iv_gen_ops->post(cc, org_iv_of_dmreq(cc, dmreq), dmreq);
2241
2242	if (error == -EBADMSG) {
2243		sector_t s = le64_to_cpu(*org_sector_of_dmreq(cc, dmreq));
2244
2245		ctx->aead_failed = true;
2246		if (ctx->aead_recheck) {
2247			DMERR_LIMIT("%pg: INTEGRITY AEAD ERROR, sector %llu",
2248				    ctx->bio_in->bi_bdev, s);
2249			dm_audit_log_bio(DM_MSG_PREFIX, "integrity-aead",
2250					 ctx->bio_in, s, 0);
2251		}
2252		io->error = BLK_STS_PROTECTION;
2253	} else if (error < 0)
2254		io->error = BLK_STS_IOERR;
2255
2256	crypt_free_req(cc, req_of_dmreq(cc, dmreq), io->base_bio);
2257
2258	if (!atomic_dec_and_test(&ctx->cc_pending))
2259		return;
2260
2261	/*
2262	 * The request is fully completed: for inline writes, let
2263	 * kcryptd_crypt_write_convert() do the IO submission.
2264	 */
2265	if (bio_data_dir(io->base_bio) == READ) {
2266		kcryptd_crypt_read_done(io);
2267		return;
2268	}
2269
2270	if (kcryptd_crypt_write_inline(cc, ctx)) {
2271		complete(&ctx->restart);
2272		return;
2273	}
2274
2275	kcryptd_crypt_write_io_submit(io, 1);
2276}
2277
2278static void kcryptd_crypt(struct work_struct *work)
2279{
2280	struct dm_crypt_io *io = container_of(work, struct dm_crypt_io, work);
2281
2282	if (bio_data_dir(io->base_bio) == READ)
2283		kcryptd_crypt_read_convert(io);
2284	else
2285		kcryptd_crypt_write_convert(io);
2286}
2287
 
 
 
 
 
2288static void kcryptd_queue_crypt(struct dm_crypt_io *io)
2289{
2290	struct crypt_config *cc = io->cc;
2291
2292	if ((bio_data_dir(io->base_bio) == READ && test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags)) ||
2293	    (bio_data_dir(io->base_bio) == WRITE && test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))) {
2294		/*
2295		 * in_hardirq(): Crypto API's skcipher_walk_first() refuses to work in hard IRQ context.
2296		 * irqs_disabled(): the kernel may run some IO completion from the idle thread, but
2297		 * it is being executed with irqs disabled.
2298		 */
2299		if (!(in_hardirq() || irqs_disabled())) {
2300			kcryptd_crypt(&io->work);
2301			return;
2302		}
 
 
 
2303	}
2304
2305	INIT_WORK(&io->work, kcryptd_crypt);
2306	queue_work(cc->crypt_queue, &io->work);
2307}
2308
2309static void crypt_free_tfms_aead(struct crypt_config *cc)
2310{
2311	if (!cc->cipher_tfm.tfms_aead)
2312		return;
2313
2314	if (cc->cipher_tfm.tfms_aead[0] && !IS_ERR(cc->cipher_tfm.tfms_aead[0])) {
2315		crypto_free_aead(cc->cipher_tfm.tfms_aead[0]);
2316		cc->cipher_tfm.tfms_aead[0] = NULL;
2317	}
2318
2319	kfree(cc->cipher_tfm.tfms_aead);
2320	cc->cipher_tfm.tfms_aead = NULL;
2321}
2322
2323static void crypt_free_tfms_skcipher(struct crypt_config *cc)
2324{
2325	unsigned int i;
2326
2327	if (!cc->cipher_tfm.tfms)
2328		return;
2329
2330	for (i = 0; i < cc->tfms_count; i++)
2331		if (cc->cipher_tfm.tfms[i] && !IS_ERR(cc->cipher_tfm.tfms[i])) {
2332			crypto_free_skcipher(cc->cipher_tfm.tfms[i]);
2333			cc->cipher_tfm.tfms[i] = NULL;
2334		}
2335
2336	kfree(cc->cipher_tfm.tfms);
2337	cc->cipher_tfm.tfms = NULL;
2338}
2339
2340static void crypt_free_tfms(struct crypt_config *cc)
2341{
2342	if (crypt_integrity_aead(cc))
2343		crypt_free_tfms_aead(cc);
2344	else
2345		crypt_free_tfms_skcipher(cc);
2346}
2347
2348static int crypt_alloc_tfms_skcipher(struct crypt_config *cc, char *ciphermode)
2349{
2350	unsigned int i;
2351	int err;
2352
2353	cc->cipher_tfm.tfms = kcalloc(cc->tfms_count,
2354				      sizeof(struct crypto_skcipher *),
2355				      GFP_KERNEL);
2356	if (!cc->cipher_tfm.tfms)
2357		return -ENOMEM;
2358
2359	for (i = 0; i < cc->tfms_count; i++) {
2360		cc->cipher_tfm.tfms[i] = crypto_alloc_skcipher(ciphermode, 0,
2361						CRYPTO_ALG_ALLOCATES_MEMORY);
2362		if (IS_ERR(cc->cipher_tfm.tfms[i])) {
2363			err = PTR_ERR(cc->cipher_tfm.tfms[i]);
2364			crypt_free_tfms(cc);
2365			return err;
2366		}
2367	}
2368
2369	/*
2370	 * dm-crypt performance can vary greatly depending on which crypto
2371	 * algorithm implementation is used.  Help people debug performance
2372	 * problems by logging the ->cra_driver_name.
2373	 */
2374	DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode,
2375	       crypto_skcipher_alg(any_tfm(cc))->base.cra_driver_name);
2376	return 0;
2377}
2378
2379static int crypt_alloc_tfms_aead(struct crypt_config *cc, char *ciphermode)
2380{
2381	int err;
2382
2383	cc->cipher_tfm.tfms = kmalloc(sizeof(struct crypto_aead *), GFP_KERNEL);
2384	if (!cc->cipher_tfm.tfms)
2385		return -ENOMEM;
2386
2387	cc->cipher_tfm.tfms_aead[0] = crypto_alloc_aead(ciphermode, 0,
2388						CRYPTO_ALG_ALLOCATES_MEMORY);
2389	if (IS_ERR(cc->cipher_tfm.tfms_aead[0])) {
2390		err = PTR_ERR(cc->cipher_tfm.tfms_aead[0]);
2391		crypt_free_tfms(cc);
2392		return err;
2393	}
2394
2395	DMDEBUG_LIMIT("%s using implementation \"%s\"", ciphermode,
2396	       crypto_aead_alg(any_tfm_aead(cc))->base.cra_driver_name);
2397	return 0;
2398}
2399
2400static int crypt_alloc_tfms(struct crypt_config *cc, char *ciphermode)
2401{
2402	if (crypt_integrity_aead(cc))
2403		return crypt_alloc_tfms_aead(cc, ciphermode);
2404	else
2405		return crypt_alloc_tfms_skcipher(cc, ciphermode);
2406}
2407
2408static unsigned int crypt_subkey_size(struct crypt_config *cc)
2409{
2410	return (cc->key_size - cc->key_extra_size) >> ilog2(cc->tfms_count);
2411}
2412
2413static unsigned int crypt_authenckey_size(struct crypt_config *cc)
2414{
2415	return crypt_subkey_size(cc) + RTA_SPACE(sizeof(struct crypto_authenc_key_param));
2416}
2417
2418/*
2419 * If AEAD is composed like authenc(hmac(sha256),xts(aes)),
2420 * the key must be for some reason in special format.
2421 * This funcion converts cc->key to this special format.
2422 */
2423static void crypt_copy_authenckey(char *p, const void *key,
2424				  unsigned int enckeylen, unsigned int authkeylen)
2425{
2426	struct crypto_authenc_key_param *param;
2427	struct rtattr *rta;
2428
2429	rta = (struct rtattr *)p;
2430	param = RTA_DATA(rta);
2431	param->enckeylen = cpu_to_be32(enckeylen);
2432	rta->rta_len = RTA_LENGTH(sizeof(*param));
2433	rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM;
2434	p += RTA_SPACE(sizeof(*param));
2435	memcpy(p, key + enckeylen, authkeylen);
2436	p += authkeylen;
2437	memcpy(p, key, enckeylen);
2438}
2439
2440static int crypt_setkey(struct crypt_config *cc)
2441{
2442	unsigned int subkey_size;
2443	int err = 0, i, r;
2444
2445	/* Ignore extra keys (which are used for IV etc) */
2446	subkey_size = crypt_subkey_size(cc);
2447
2448	if (crypt_integrity_hmac(cc)) {
2449		if (subkey_size < cc->key_mac_size)
2450			return -EINVAL;
2451
2452		crypt_copy_authenckey(cc->authenc_key, cc->key,
2453				      subkey_size - cc->key_mac_size,
2454				      cc->key_mac_size);
2455	}
2456
2457	for (i = 0; i < cc->tfms_count; i++) {
2458		if (crypt_integrity_hmac(cc))
2459			r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i],
2460				cc->authenc_key, crypt_authenckey_size(cc));
2461		else if (crypt_integrity_aead(cc))
2462			r = crypto_aead_setkey(cc->cipher_tfm.tfms_aead[i],
2463					       cc->key + (i * subkey_size),
2464					       subkey_size);
2465		else
2466			r = crypto_skcipher_setkey(cc->cipher_tfm.tfms[i],
2467						   cc->key + (i * subkey_size),
2468						   subkey_size);
2469		if (r)
2470			err = r;
2471	}
2472
2473	if (crypt_integrity_hmac(cc))
2474		memzero_explicit(cc->authenc_key, crypt_authenckey_size(cc));
2475
2476	return err;
2477}
2478
2479#ifdef CONFIG_KEYS
2480
2481static bool contains_whitespace(const char *str)
2482{
2483	while (*str)
2484		if (isspace(*str++))
2485			return true;
2486	return false;
2487}
2488
2489static int set_key_user(struct crypt_config *cc, struct key *key)
2490{
2491	const struct user_key_payload *ukp;
2492
2493	ukp = user_key_payload_locked(key);
2494	if (!ukp)
2495		return -EKEYREVOKED;
2496
2497	if (cc->key_size != ukp->datalen)
2498		return -EINVAL;
2499
2500	memcpy(cc->key, ukp->data, cc->key_size);
2501
2502	return 0;
2503}
2504
 
2505static int set_key_encrypted(struct crypt_config *cc, struct key *key)
2506{
2507	const struct encrypted_key_payload *ekp;
2508
2509	ekp = key->payload.data[0];
2510	if (!ekp)
2511		return -EKEYREVOKED;
2512
2513	if (cc->key_size != ekp->decrypted_datalen)
2514		return -EINVAL;
2515
2516	memcpy(cc->key, ekp->decrypted_data, cc->key_size);
2517
2518	return 0;
2519}
2520
2521static int set_key_trusted(struct crypt_config *cc, struct key *key)
2522{
2523	const struct trusted_key_payload *tkp;
2524
2525	tkp = key->payload.data[0];
2526	if (!tkp)
2527		return -EKEYREVOKED;
2528
2529	if (cc->key_size != tkp->key_len)
2530		return -EINVAL;
2531
2532	memcpy(cc->key, tkp->key, cc->key_size);
2533
2534	return 0;
2535}
2536
2537static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string)
2538{
2539	char *new_key_string, *key_desc;
2540	int ret;
2541	struct key_type *type;
2542	struct key *key;
2543	int (*set_key)(struct crypt_config *cc, struct key *key);
2544
2545	/*
2546	 * Reject key_string with whitespace. dm core currently lacks code for
2547	 * proper whitespace escaping in arguments on DM_TABLE_STATUS path.
2548	 */
2549	if (contains_whitespace(key_string)) {
2550		DMERR("whitespace chars not allowed in key string");
2551		return -EINVAL;
2552	}
2553
2554	/* look for next ':' separating key_type from key_description */
2555	key_desc = strchr(key_string, ':');
2556	if (!key_desc || key_desc == key_string || !strlen(key_desc + 1))
2557		return -EINVAL;
2558
2559	if (!strncmp(key_string, "logon:", key_desc - key_string + 1)) {
2560		type = &key_type_logon;
2561		set_key = set_key_user;
2562	} else if (!strncmp(key_string, "user:", key_desc - key_string + 1)) {
2563		type = &key_type_user;
2564		set_key = set_key_user;
2565	} else if (IS_ENABLED(CONFIG_ENCRYPTED_KEYS) &&
2566		   !strncmp(key_string, "encrypted:", key_desc - key_string + 1)) {
2567		type = &key_type_encrypted;
2568		set_key = set_key_encrypted;
2569	} else if (IS_ENABLED(CONFIG_TRUSTED_KEYS) &&
2570		   !strncmp(key_string, "trusted:", key_desc - key_string + 1)) {
2571		type = &key_type_trusted;
2572		set_key = set_key_trusted;
2573	} else {
2574		return -EINVAL;
2575	}
2576
2577	new_key_string = kstrdup(key_string, GFP_KERNEL);
2578	if (!new_key_string)
2579		return -ENOMEM;
2580
2581	key = request_key(type, key_desc + 1, NULL);
2582	if (IS_ERR(key)) {
2583		kfree_sensitive(new_key_string);
2584		return PTR_ERR(key);
2585	}
2586
2587	down_read(&key->sem);
2588
2589	ret = set_key(cc, key);
2590	if (ret < 0) {
2591		up_read(&key->sem);
2592		key_put(key);
2593		kfree_sensitive(new_key_string);
2594		return ret;
2595	}
2596
2597	up_read(&key->sem);
2598	key_put(key);
2599
2600	/* clear the flag since following operations may invalidate previously valid key */
2601	clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2602
2603	ret = crypt_setkey(cc);
2604
2605	if (!ret) {
2606		set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2607		kfree_sensitive(cc->key_string);
2608		cc->key_string = new_key_string;
2609	} else
2610		kfree_sensitive(new_key_string);
2611
2612	return ret;
2613}
2614
2615static int get_key_size(char **key_string)
2616{
2617	char *colon, dummy;
2618	int ret;
2619
2620	if (*key_string[0] != ':')
2621		return strlen(*key_string) >> 1;
2622
2623	/* look for next ':' in key string */
2624	colon = strpbrk(*key_string + 1, ":");
2625	if (!colon)
2626		return -EINVAL;
2627
2628	if (sscanf(*key_string + 1, "%u%c", &ret, &dummy) != 2 || dummy != ':')
2629		return -EINVAL;
2630
2631	*key_string = colon;
2632
2633	/* remaining key string should be :<logon|user>:<key_desc> */
2634
2635	return ret;
2636}
2637
2638#else
2639
2640static int crypt_set_keyring_key(struct crypt_config *cc, const char *key_string)
2641{
2642	return -EINVAL;
2643}
2644
2645static int get_key_size(char **key_string)
2646{
2647	return (*key_string[0] == ':') ? -EINVAL : (int)(strlen(*key_string) >> 1);
2648}
2649
2650#endif /* CONFIG_KEYS */
2651
2652static int crypt_set_key(struct crypt_config *cc, char *key)
2653{
2654	int r = -EINVAL;
2655	int key_string_len = strlen(key);
2656
2657	/* Hyphen (which gives a key_size of zero) means there is no key. */
2658	if (!cc->key_size && strcmp(key, "-"))
2659		goto out;
2660
2661	/* ':' means the key is in kernel keyring, short-circuit normal key processing */
2662	if (key[0] == ':') {
2663		r = crypt_set_keyring_key(cc, key + 1);
2664		goto out;
2665	}
2666
2667	/* clear the flag since following operations may invalidate previously valid key */
2668	clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2669
2670	/* wipe references to any kernel keyring key */
2671	kfree_sensitive(cc->key_string);
2672	cc->key_string = NULL;
2673
2674	/* Decode key from its hex representation. */
2675	if (cc->key_size && hex2bin(cc->key, key, cc->key_size) < 0)
2676		goto out;
2677
2678	r = crypt_setkey(cc);
2679	if (!r)
2680		set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2681
2682out:
2683	/* Hex key string not needed after here, so wipe it. */
2684	memset(key, '0', key_string_len);
2685
2686	return r;
2687}
2688
2689static int crypt_wipe_key(struct crypt_config *cc)
2690{
2691	int r;
2692
2693	clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
2694	get_random_bytes(&cc->key, cc->key_size);
2695
2696	/* Wipe IV private keys */
2697	if (cc->iv_gen_ops && cc->iv_gen_ops->wipe) {
2698		r = cc->iv_gen_ops->wipe(cc);
2699		if (r)
2700			return r;
2701	}
2702
2703	kfree_sensitive(cc->key_string);
2704	cc->key_string = NULL;
2705	r = crypt_setkey(cc);
2706	memset(&cc->key, 0, cc->key_size * sizeof(u8));
2707
2708	return r;
2709}
2710
2711static void crypt_calculate_pages_per_client(void)
2712{
2713	unsigned long pages = (totalram_pages() - totalhigh_pages()) * DM_CRYPT_MEMORY_PERCENT / 100;
2714
2715	if (!dm_crypt_clients_n)
2716		return;
2717
2718	pages /= dm_crypt_clients_n;
2719	if (pages < DM_CRYPT_MIN_PAGES_PER_CLIENT)
2720		pages = DM_CRYPT_MIN_PAGES_PER_CLIENT;
2721	dm_crypt_pages_per_client = pages;
2722}
2723
2724static void *crypt_page_alloc(gfp_t gfp_mask, void *pool_data)
2725{
2726	struct crypt_config *cc = pool_data;
2727	struct page *page;
2728
2729	/*
2730	 * Note, percpu_counter_read_positive() may over (and under) estimate
2731	 * the current usage by at most (batch - 1) * num_online_cpus() pages,
2732	 * but avoids potential spinlock contention of an exact result.
2733	 */
2734	if (unlikely(percpu_counter_read_positive(&cc->n_allocated_pages) >= dm_crypt_pages_per_client) &&
2735	    likely(gfp_mask & __GFP_NORETRY))
2736		return NULL;
2737
2738	page = alloc_page(gfp_mask);
2739	if (likely(page != NULL))
2740		percpu_counter_add(&cc->n_allocated_pages, 1);
2741
2742	return page;
2743}
2744
2745static void crypt_page_free(void *page, void *pool_data)
2746{
2747	struct crypt_config *cc = pool_data;
2748
2749	__free_page(page);
2750	percpu_counter_sub(&cc->n_allocated_pages, 1);
2751}
2752
2753static void crypt_dtr(struct dm_target *ti)
2754{
2755	struct crypt_config *cc = ti->private;
2756
2757	ti->private = NULL;
2758
2759	if (!cc)
2760		return;
2761
2762	if (cc->write_thread)
2763		kthread_stop(cc->write_thread);
2764
2765	if (cc->io_queue)
2766		destroy_workqueue(cc->io_queue);
2767	if (cc->crypt_queue)
2768		destroy_workqueue(cc->crypt_queue);
2769
2770	crypt_free_tfms(cc);
2771
2772	bioset_exit(&cc->bs);
2773
2774	mempool_exit(&cc->page_pool);
2775	mempool_exit(&cc->req_pool);
2776	mempool_exit(&cc->tag_pool);
2777
2778	WARN_ON(percpu_counter_sum(&cc->n_allocated_pages) != 0);
2779	percpu_counter_destroy(&cc->n_allocated_pages);
2780
2781	if (cc->iv_gen_ops && cc->iv_gen_ops->dtr)
2782		cc->iv_gen_ops->dtr(cc);
2783
2784	if (cc->dev)
2785		dm_put_device(ti, cc->dev);
2786
2787	kfree_sensitive(cc->cipher_string);
2788	kfree_sensitive(cc->key_string);
2789	kfree_sensitive(cc->cipher_auth);
2790	kfree_sensitive(cc->authenc_key);
2791
2792	mutex_destroy(&cc->bio_alloc_lock);
2793
2794	/* Must zero key material before freeing */
2795	kfree_sensitive(cc);
2796
2797	spin_lock(&dm_crypt_clients_lock);
2798	WARN_ON(!dm_crypt_clients_n);
2799	dm_crypt_clients_n--;
2800	crypt_calculate_pages_per_client();
2801	spin_unlock(&dm_crypt_clients_lock);
2802
2803	dm_audit_log_dtr(DM_MSG_PREFIX, ti, 1);
2804}
2805
2806static int crypt_ctr_ivmode(struct dm_target *ti, const char *ivmode)
2807{
2808	struct crypt_config *cc = ti->private;
2809
2810	if (crypt_integrity_aead(cc))
2811		cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc));
2812	else
2813		cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));
2814
2815	if (cc->iv_size)
2816		/* at least a 64 bit sector number should fit in our buffer */
2817		cc->iv_size = max(cc->iv_size,
2818				  (unsigned int)(sizeof(u64) / sizeof(u8)));
2819	else if (ivmode) {
2820		DMWARN("Selected cipher does not support IVs");
2821		ivmode = NULL;
2822	}
2823
2824	/* Choose ivmode, see comments at iv code. */
2825	if (ivmode == NULL)
2826		cc->iv_gen_ops = NULL;
2827	else if (strcmp(ivmode, "plain") == 0)
2828		cc->iv_gen_ops = &crypt_iv_plain_ops;
2829	else if (strcmp(ivmode, "plain64") == 0)
2830		cc->iv_gen_ops = &crypt_iv_plain64_ops;
2831	else if (strcmp(ivmode, "plain64be") == 0)
2832		cc->iv_gen_ops = &crypt_iv_plain64be_ops;
2833	else if (strcmp(ivmode, "essiv") == 0)
2834		cc->iv_gen_ops = &crypt_iv_essiv_ops;
2835	else if (strcmp(ivmode, "benbi") == 0)
2836		cc->iv_gen_ops = &crypt_iv_benbi_ops;
2837	else if (strcmp(ivmode, "null") == 0)
2838		cc->iv_gen_ops = &crypt_iv_null_ops;
2839	else if (strcmp(ivmode, "eboiv") == 0)
2840		cc->iv_gen_ops = &crypt_iv_eboiv_ops;
2841	else if (strcmp(ivmode, "elephant") == 0) {
2842		cc->iv_gen_ops = &crypt_iv_elephant_ops;
2843		cc->key_parts = 2;
2844		cc->key_extra_size = cc->key_size / 2;
2845		if (cc->key_extra_size > ELEPHANT_MAX_KEY_SIZE)
2846			return -EINVAL;
2847		set_bit(CRYPT_ENCRYPT_PREPROCESS, &cc->cipher_flags);
2848	} else if (strcmp(ivmode, "lmk") == 0) {
2849		cc->iv_gen_ops = &crypt_iv_lmk_ops;
2850		/*
2851		 * Version 2 and 3 is recognised according
2852		 * to length of provided multi-key string.
2853		 * If present (version 3), last key is used as IV seed.
2854		 * All keys (including IV seed) are always the same size.
2855		 */
2856		if (cc->key_size % cc->key_parts) {
2857			cc->key_parts++;
2858			cc->key_extra_size = cc->key_size / cc->key_parts;
2859		}
2860	} else if (strcmp(ivmode, "tcw") == 0) {
2861		cc->iv_gen_ops = &crypt_iv_tcw_ops;
2862		cc->key_parts += 2; /* IV + whitening */
2863		cc->key_extra_size = cc->iv_size + TCW_WHITENING_SIZE;
2864	} else if (strcmp(ivmode, "random") == 0) {
2865		cc->iv_gen_ops = &crypt_iv_random_ops;
2866		/* Need storage space in integrity fields. */
2867		cc->integrity_iv_size = cc->iv_size;
2868	} else {
2869		ti->error = "Invalid IV mode";
2870		return -EINVAL;
2871	}
2872
2873	return 0;
2874}
2875
2876/*
2877 * Workaround to parse HMAC algorithm from AEAD crypto API spec.
2878 * The HMAC is needed to calculate tag size (HMAC digest size).
2879 * This should be probably done by crypto-api calls (once available...)
2880 */
2881static int crypt_ctr_auth_cipher(struct crypt_config *cc, char *cipher_api)
2882{
2883	char *start, *end, *mac_alg = NULL;
2884	struct crypto_ahash *mac;
2885
2886	if (!strstarts(cipher_api, "authenc("))
2887		return 0;
2888
2889	start = strchr(cipher_api, '(');
2890	end = strchr(cipher_api, ',');
2891	if (!start || !end || ++start > end)
2892		return -EINVAL;
2893
2894	mac_alg = kmemdup_nul(start, end - start, GFP_KERNEL);
2895	if (!mac_alg)
2896		return -ENOMEM;
 
2897
2898	mac = crypto_alloc_ahash(mac_alg, 0, CRYPTO_ALG_ALLOCATES_MEMORY);
2899	kfree(mac_alg);
2900
2901	if (IS_ERR(mac))
2902		return PTR_ERR(mac);
2903
2904	cc->key_mac_size = crypto_ahash_digestsize(mac);
2905	crypto_free_ahash(mac);
2906
2907	cc->authenc_key = kmalloc(crypt_authenckey_size(cc), GFP_KERNEL);
2908	if (!cc->authenc_key)
2909		return -ENOMEM;
2910
2911	return 0;
2912}
2913
2914static int crypt_ctr_cipher_new(struct dm_target *ti, char *cipher_in, char *key,
2915				char **ivmode, char **ivopts)
2916{
2917	struct crypt_config *cc = ti->private;
2918	char *tmp, *cipher_api, buf[CRYPTO_MAX_ALG_NAME];
2919	int ret = -EINVAL;
2920
2921	cc->tfms_count = 1;
2922
2923	/*
2924	 * New format (capi: prefix)
2925	 * capi:cipher_api_spec-iv:ivopts
2926	 */
2927	tmp = &cipher_in[strlen("capi:")];
2928
2929	/* Separate IV options if present, it can contain another '-' in hash name */
2930	*ivopts = strrchr(tmp, ':');
2931	if (*ivopts) {
2932		**ivopts = '\0';
2933		(*ivopts)++;
2934	}
2935	/* Parse IV mode */
2936	*ivmode = strrchr(tmp, '-');
2937	if (*ivmode) {
2938		**ivmode = '\0';
2939		(*ivmode)++;
2940	}
2941	/* The rest is crypto API spec */
2942	cipher_api = tmp;
2943
2944	/* Alloc AEAD, can be used only in new format. */
2945	if (crypt_integrity_aead(cc)) {
2946		ret = crypt_ctr_auth_cipher(cc, cipher_api);
2947		if (ret < 0) {
2948			ti->error = "Invalid AEAD cipher spec";
2949			return ret;
2950		}
2951	}
2952
2953	if (*ivmode && !strcmp(*ivmode, "lmk"))
2954		cc->tfms_count = 64;
2955
2956	if (*ivmode && !strcmp(*ivmode, "essiv")) {
2957		if (!*ivopts) {
2958			ti->error = "Digest algorithm missing for ESSIV mode";
2959			return -EINVAL;
2960		}
2961		ret = snprintf(buf, CRYPTO_MAX_ALG_NAME, "essiv(%s,%s)",
2962			       cipher_api, *ivopts);
2963		if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) {
2964			ti->error = "Cannot allocate cipher string";
2965			return -ENOMEM;
2966		}
2967		cipher_api = buf;
2968	}
2969
2970	cc->key_parts = cc->tfms_count;
2971
2972	/* Allocate cipher */
2973	ret = crypt_alloc_tfms(cc, cipher_api);
2974	if (ret < 0) {
2975		ti->error = "Error allocating crypto tfm";
2976		return ret;
2977	}
2978
2979	if (crypt_integrity_aead(cc))
2980		cc->iv_size = crypto_aead_ivsize(any_tfm_aead(cc));
2981	else
2982		cc->iv_size = crypto_skcipher_ivsize(any_tfm(cc));
2983
2984	return 0;
2985}
2986
2987static int crypt_ctr_cipher_old(struct dm_target *ti, char *cipher_in, char *key,
2988				char **ivmode, char **ivopts)
2989{
2990	struct crypt_config *cc = ti->private;
2991	char *tmp, *cipher, *chainmode, *keycount;
2992	char *cipher_api = NULL;
2993	int ret = -EINVAL;
2994	char dummy;
2995
2996	if (strchr(cipher_in, '(') || crypt_integrity_aead(cc)) {
2997		ti->error = "Bad cipher specification";
2998		return -EINVAL;
2999	}
3000
3001	/*
3002	 * Legacy dm-crypt cipher specification
3003	 * cipher[:keycount]-mode-iv:ivopts
3004	 */
3005	tmp = cipher_in;
3006	keycount = strsep(&tmp, "-");
3007	cipher = strsep(&keycount, ":");
3008
3009	if (!keycount)
3010		cc->tfms_count = 1;
3011	else if (sscanf(keycount, "%u%c", &cc->tfms_count, &dummy) != 1 ||
3012		 !is_power_of_2(cc->tfms_count)) {
3013		ti->error = "Bad cipher key count specification";
3014		return -EINVAL;
3015	}
3016	cc->key_parts = cc->tfms_count;
3017
3018	chainmode = strsep(&tmp, "-");
3019	*ivmode = strsep(&tmp, ":");
3020	*ivopts = tmp;
3021
3022	/*
3023	 * For compatibility with the original dm-crypt mapping format, if
3024	 * only the cipher name is supplied, use cbc-plain.
3025	 */
3026	if (!chainmode || (!strcmp(chainmode, "plain") && !*ivmode)) {
3027		chainmode = "cbc";
3028		*ivmode = "plain";
3029	}
3030
3031	if (strcmp(chainmode, "ecb") && !*ivmode) {
3032		ti->error = "IV mechanism required";
3033		return -EINVAL;
3034	}
3035
3036	cipher_api = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL);
3037	if (!cipher_api)
3038		goto bad_mem;
3039
3040	if (*ivmode && !strcmp(*ivmode, "essiv")) {
3041		if (!*ivopts) {
3042			ti->error = "Digest algorithm missing for ESSIV mode";
3043			kfree(cipher_api);
3044			return -EINVAL;
3045		}
3046		ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
3047			       "essiv(%s(%s),%s)", chainmode, cipher, *ivopts);
3048	} else {
3049		ret = snprintf(cipher_api, CRYPTO_MAX_ALG_NAME,
3050			       "%s(%s)", chainmode, cipher);
3051	}
3052	if (ret < 0 || ret >= CRYPTO_MAX_ALG_NAME) {
3053		kfree(cipher_api);
3054		goto bad_mem;
3055	}
3056
3057	/* Allocate cipher */
3058	ret = crypt_alloc_tfms(cc, cipher_api);
3059	if (ret < 0) {
3060		ti->error = "Error allocating crypto tfm";
3061		kfree(cipher_api);
3062		return ret;
3063	}
3064	kfree(cipher_api);
3065
3066	return 0;
3067bad_mem:
3068	ti->error = "Cannot allocate cipher strings";
3069	return -ENOMEM;
3070}
3071
3072static int crypt_ctr_cipher(struct dm_target *ti, char *cipher_in, char *key)
3073{
3074	struct crypt_config *cc = ti->private;
3075	char *ivmode = NULL, *ivopts = NULL;
3076	int ret;
3077
3078	cc->cipher_string = kstrdup(cipher_in, GFP_KERNEL);
3079	if (!cc->cipher_string) {
3080		ti->error = "Cannot allocate cipher strings";
3081		return -ENOMEM;
3082	}
3083
3084	if (strstarts(cipher_in, "capi:"))
3085		ret = crypt_ctr_cipher_new(ti, cipher_in, key, &ivmode, &ivopts);
3086	else
3087		ret = crypt_ctr_cipher_old(ti, cipher_in, key, &ivmode, &ivopts);
3088	if (ret)
3089		return ret;
3090
3091	/* Initialize IV */
3092	ret = crypt_ctr_ivmode(ti, ivmode);
3093	if (ret < 0)
3094		return ret;
3095
3096	/* Initialize and set key */
3097	ret = crypt_set_key(cc, key);
3098	if (ret < 0) {
3099		ti->error = "Error decoding and setting key";
3100		return ret;
3101	}
3102
3103	/* Allocate IV */
3104	if (cc->iv_gen_ops && cc->iv_gen_ops->ctr) {
3105		ret = cc->iv_gen_ops->ctr(cc, ti, ivopts);
3106		if (ret < 0) {
3107			ti->error = "Error creating IV";
3108			return ret;
3109		}
3110	}
3111
3112	/* Initialize IV (set keys for ESSIV etc) */
3113	if (cc->iv_gen_ops && cc->iv_gen_ops->init) {
3114		ret = cc->iv_gen_ops->init(cc);
3115		if (ret < 0) {
3116			ti->error = "Error initialising IV";
3117			return ret;
3118		}
3119	}
3120
3121	/* wipe the kernel key payload copy */
3122	if (cc->key_string)
3123		memset(cc->key, 0, cc->key_size * sizeof(u8));
3124
3125	return ret;
3126}
3127
3128static int crypt_ctr_optional(struct dm_target *ti, unsigned int argc, char **argv)
3129{
3130	struct crypt_config *cc = ti->private;
3131	struct dm_arg_set as;
3132	static const struct dm_arg _args[] = {
3133		{0, 8, "Invalid number of feature args"},
3134	};
3135	unsigned int opt_params, val;
3136	const char *opt_string, *sval;
3137	char dummy;
3138	int ret;
3139
3140	/* Optional parameters */
3141	as.argc = argc;
3142	as.argv = argv;
3143
3144	ret = dm_read_arg_group(_args, &as, &opt_params, &ti->error);
3145	if (ret)
3146		return ret;
3147
3148	while (opt_params--) {
3149		opt_string = dm_shift_arg(&as);
3150		if (!opt_string) {
3151			ti->error = "Not enough feature arguments";
3152			return -EINVAL;
3153		}
3154
3155		if (!strcasecmp(opt_string, "allow_discards"))
3156			ti->num_discard_bios = 1;
3157
3158		else if (!strcasecmp(opt_string, "same_cpu_crypt"))
3159			set_bit(DM_CRYPT_SAME_CPU, &cc->flags);
3160
3161		else if (!strcasecmp(opt_string, "submit_from_crypt_cpus"))
3162			set_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags);
3163		else if (!strcasecmp(opt_string, "no_read_workqueue"))
3164			set_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags);
3165		else if (!strcasecmp(opt_string, "no_write_workqueue"))
3166			set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
3167		else if (sscanf(opt_string, "integrity:%u:", &val) == 1) {
3168			if (val == 0 || val > MAX_TAG_SIZE) {
3169				ti->error = "Invalid integrity arguments";
3170				return -EINVAL;
3171			}
3172			cc->on_disk_tag_size = val;
3173			sval = strchr(opt_string + strlen("integrity:"), ':') + 1;
3174			if (!strcasecmp(sval, "aead")) {
3175				set_bit(CRYPT_MODE_INTEGRITY_AEAD, &cc->cipher_flags);
3176			} else if (strcasecmp(sval, "none")) {
3177				ti->error = "Unknown integrity profile";
3178				return -EINVAL;
3179			}
3180
3181			cc->cipher_auth = kstrdup(sval, GFP_KERNEL);
3182			if (!cc->cipher_auth)
3183				return -ENOMEM;
3184		} else if (sscanf(opt_string, "sector_size:%hu%c", &cc->sector_size, &dummy) == 1) {
3185			if (cc->sector_size < (1 << SECTOR_SHIFT) ||
3186			    cc->sector_size > 4096 ||
3187			    (cc->sector_size & (cc->sector_size - 1))) {
3188				ti->error = "Invalid feature value for sector_size";
3189				return -EINVAL;
3190			}
3191			if (ti->len & ((cc->sector_size >> SECTOR_SHIFT) - 1)) {
3192				ti->error = "Device size is not multiple of sector_size feature";
3193				return -EINVAL;
3194			}
3195			cc->sector_shift = __ffs(cc->sector_size) - SECTOR_SHIFT;
3196		} else if (!strcasecmp(opt_string, "iv_large_sectors"))
3197			set_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags);
3198		else {
3199			ti->error = "Invalid feature arguments";
3200			return -EINVAL;
3201		}
3202	}
3203
3204	return 0;
3205}
3206
3207#ifdef CONFIG_BLK_DEV_ZONED
 
3208static int crypt_report_zones(struct dm_target *ti,
3209		struct dm_report_zones_args *args, unsigned int nr_zones)
3210{
3211	struct crypt_config *cc = ti->private;
 
3212
3213	return dm_report_zones(cc->dev->bdev, cc->start,
3214			cc->start + dm_target_offset(ti, args->next_sector),
3215			args, nr_zones);
3216}
3217#else
3218#define crypt_report_zones NULL
3219#endif
3220
3221/*
3222 * Construct an encryption mapping:
3223 * <cipher> [<key>|:<key_size>:<user|logon>:<key_description>] <iv_offset> <dev_path> <start>
3224 */
3225static int crypt_ctr(struct dm_target *ti, unsigned int argc, char **argv)
3226{
3227	struct crypt_config *cc;
3228	const char *devname = dm_table_device_name(ti->table);
3229	int key_size;
3230	unsigned int align_mask;
3231	unsigned long long tmpll;
3232	int ret;
3233	size_t iv_size_padding, additional_req_size;
3234	char dummy;
3235
3236	if (argc < 5) {
3237		ti->error = "Not enough arguments";
3238		return -EINVAL;
3239	}
3240
3241	key_size = get_key_size(&argv[1]);
3242	if (key_size < 0) {
3243		ti->error = "Cannot parse key size";
3244		return -EINVAL;
3245	}
3246
3247	cc = kzalloc(struct_size(cc, key, key_size), GFP_KERNEL);
3248	if (!cc) {
3249		ti->error = "Cannot allocate encryption context";
3250		return -ENOMEM;
3251	}
3252	cc->key_size = key_size;
3253	cc->sector_size = (1 << SECTOR_SHIFT);
3254	cc->sector_shift = 0;
3255
3256	ti->private = cc;
3257
3258	spin_lock(&dm_crypt_clients_lock);
3259	dm_crypt_clients_n++;
3260	crypt_calculate_pages_per_client();
3261	spin_unlock(&dm_crypt_clients_lock);
3262
3263	ret = percpu_counter_init(&cc->n_allocated_pages, 0, GFP_KERNEL);
3264	if (ret < 0)
3265		goto bad;
3266
3267	/* Optional parameters need to be read before cipher constructor */
3268	if (argc > 5) {
3269		ret = crypt_ctr_optional(ti, argc - 5, &argv[5]);
3270		if (ret)
3271			goto bad;
3272	}
3273
3274	ret = crypt_ctr_cipher(ti, argv[0], argv[1]);
3275	if (ret < 0)
3276		goto bad;
3277
3278	if (crypt_integrity_aead(cc)) {
3279		cc->dmreq_start = sizeof(struct aead_request);
3280		cc->dmreq_start += crypto_aead_reqsize(any_tfm_aead(cc));
3281		align_mask = crypto_aead_alignmask(any_tfm_aead(cc));
3282	} else {
3283		cc->dmreq_start = sizeof(struct skcipher_request);
3284		cc->dmreq_start += crypto_skcipher_reqsize(any_tfm(cc));
3285		align_mask = crypto_skcipher_alignmask(any_tfm(cc));
3286	}
3287	cc->dmreq_start = ALIGN(cc->dmreq_start, __alignof__(struct dm_crypt_request));
3288
3289	if (align_mask < CRYPTO_MINALIGN) {
3290		/* Allocate the padding exactly */
3291		iv_size_padding = -(cc->dmreq_start + sizeof(struct dm_crypt_request))
3292				& align_mask;
3293	} else {
3294		/*
3295		 * If the cipher requires greater alignment than kmalloc
3296		 * alignment, we don't know the exact position of the
3297		 * initialization vector. We must assume worst case.
3298		 */
3299		iv_size_padding = align_mask;
3300	}
3301
3302	/*  ...| IV + padding | original IV | original sec. number | bio tag offset | */
3303	additional_req_size = sizeof(struct dm_crypt_request) +
3304		iv_size_padding + cc->iv_size +
3305		cc->iv_size +
3306		sizeof(uint64_t) +
3307		sizeof(unsigned int);
3308
3309	ret = mempool_init_kmalloc_pool(&cc->req_pool, MIN_IOS, cc->dmreq_start + additional_req_size);
3310	if (ret) {
3311		ti->error = "Cannot allocate crypt request mempool";
3312		goto bad;
3313	}
3314
3315	cc->per_bio_data_size = ti->per_io_data_size =
3316		ALIGN(sizeof(struct dm_crypt_io) + cc->dmreq_start + additional_req_size,
3317		      ARCH_DMA_MINALIGN);
3318
3319	ret = mempool_init(&cc->page_pool, BIO_MAX_VECS, crypt_page_alloc, crypt_page_free, cc);
3320	if (ret) {
3321		ti->error = "Cannot allocate page mempool";
3322		goto bad;
3323	}
3324
3325	ret = bioset_init(&cc->bs, MIN_IOS, 0, BIOSET_NEED_BVECS);
3326	if (ret) {
3327		ti->error = "Cannot allocate crypt bioset";
3328		goto bad;
3329	}
3330
3331	mutex_init(&cc->bio_alloc_lock);
3332
3333	ret = -EINVAL;
3334	if ((sscanf(argv[2], "%llu%c", &tmpll, &dummy) != 1) ||
3335	    (tmpll & ((cc->sector_size >> SECTOR_SHIFT) - 1))) {
3336		ti->error = "Invalid iv_offset sector";
3337		goto bad;
3338	}
3339	cc->iv_offset = tmpll;
3340
3341	ret = dm_get_device(ti, argv[3], dm_table_get_mode(ti->table), &cc->dev);
3342	if (ret) {
3343		ti->error = "Device lookup failed";
3344		goto bad;
3345	}
3346
3347	ret = -EINVAL;
3348	if (sscanf(argv[4], "%llu%c", &tmpll, &dummy) != 1 || tmpll != (sector_t)tmpll) {
3349		ti->error = "Invalid device sector";
3350		goto bad;
3351	}
3352	cc->start = tmpll;
3353
 
 
 
 
 
3354	if (bdev_is_zoned(cc->dev->bdev)) {
3355		/*
3356		 * For zoned block devices, we need to preserve the issuer write
3357		 * ordering. To do so, disable write workqueues and force inline
3358		 * encryption completion.
3359		 */
3360		set_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
3361		set_bit(DM_CRYPT_WRITE_INLINE, &cc->flags);
3362
3363		/*
3364		 * All zone append writes to a zone of a zoned block device will
3365		 * have the same BIO sector, the start of the zone. When the
3366		 * cypher IV mode uses sector values, all data targeting a
3367		 * zone will be encrypted using the first sector numbers of the
3368		 * zone. This will not result in write errors but will
3369		 * cause most reads to fail as reads will use the sector values
3370		 * for the actual data locations, resulting in IV mismatch.
3371		 * To avoid this problem, ask DM core to emulate zone append
3372		 * operations with regular writes.
3373		 */
3374		DMDEBUG("Zone append operations will be emulated");
3375		ti->emulate_zone_append = true;
3376	}
3377
3378	if (crypt_integrity_aead(cc) || cc->integrity_iv_size) {
3379		ret = crypt_integrity_ctr(cc, ti);
3380		if (ret)
3381			goto bad;
3382
3383		cc->tag_pool_max_sectors = POOL_ENTRY_SIZE / cc->on_disk_tag_size;
3384		if (!cc->tag_pool_max_sectors)
3385			cc->tag_pool_max_sectors = 1;
3386
3387		ret = mempool_init_kmalloc_pool(&cc->tag_pool, MIN_IOS,
3388			cc->tag_pool_max_sectors * cc->on_disk_tag_size);
3389		if (ret) {
3390			ti->error = "Cannot allocate integrity tags mempool";
3391			goto bad;
3392		}
3393
3394		cc->tag_pool_max_sectors <<= cc->sector_shift;
3395	}
3396
3397	ret = -ENOMEM;
3398	cc->io_queue = alloc_workqueue("kcryptd_io/%s", WQ_MEM_RECLAIM, 1, devname);
3399	if (!cc->io_queue) {
3400		ti->error = "Couldn't create kcryptd io queue";
3401		goto bad;
3402	}
3403
3404	if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
3405		cc->crypt_queue = alloc_workqueue("kcryptd/%s", WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM,
3406						  1, devname);
3407	else
3408		cc->crypt_queue = alloc_workqueue("kcryptd/%s",
3409						  WQ_CPU_INTENSIVE | WQ_MEM_RECLAIM | WQ_UNBOUND,
3410						  num_online_cpus(), devname);
3411	if (!cc->crypt_queue) {
3412		ti->error = "Couldn't create kcryptd queue";
3413		goto bad;
3414	}
3415
3416	spin_lock_init(&cc->write_thread_lock);
3417	cc->write_tree = RB_ROOT;
3418
3419	cc->write_thread = kthread_run(dmcrypt_write, cc, "dmcrypt_write/%s", devname);
3420	if (IS_ERR(cc->write_thread)) {
3421		ret = PTR_ERR(cc->write_thread);
3422		cc->write_thread = NULL;
3423		ti->error = "Couldn't spawn write thread";
3424		goto bad;
3425	}
 
3426
3427	ti->num_flush_bios = 1;
3428	ti->limit_swap_bios = true;
3429	ti->accounts_remapped_io = true;
3430
3431	dm_audit_log_ctr(DM_MSG_PREFIX, ti, 1);
3432	return 0;
3433
3434bad:
3435	dm_audit_log_ctr(DM_MSG_PREFIX, ti, 0);
3436	crypt_dtr(ti);
3437	return ret;
3438}
3439
3440static int crypt_map(struct dm_target *ti, struct bio *bio)
3441{
3442	struct dm_crypt_io *io;
3443	struct crypt_config *cc = ti->private;
3444
3445	/*
3446	 * If bio is REQ_PREFLUSH or REQ_OP_DISCARD, just bypass crypt queues.
3447	 * - for REQ_PREFLUSH device-mapper core ensures that no IO is in-flight
3448	 * - for REQ_OP_DISCARD caller must use flush if IO ordering matters
3449	 */
3450	if (unlikely(bio->bi_opf & REQ_PREFLUSH ||
3451	    bio_op(bio) == REQ_OP_DISCARD)) {
3452		bio_set_dev(bio, cc->dev->bdev);
3453		if (bio_sectors(bio))
3454			bio->bi_iter.bi_sector = cc->start +
3455				dm_target_offset(ti, bio->bi_iter.bi_sector);
3456		return DM_MAPIO_REMAPPED;
3457	}
3458
3459	/*
3460	 * Check if bio is too large, split as needed.
3461	 */
3462	if (unlikely(bio->bi_iter.bi_size > (BIO_MAX_VECS << PAGE_SHIFT)) &&
3463	    (bio_data_dir(bio) == WRITE || cc->on_disk_tag_size))
3464		dm_accept_partial_bio(bio, ((BIO_MAX_VECS << PAGE_SHIFT) >> SECTOR_SHIFT));
3465
3466	/*
3467	 * Ensure that bio is a multiple of internal sector encryption size
3468	 * and is aligned to this size as defined in IO hints.
3469	 */
3470	if (unlikely((bio->bi_iter.bi_sector & ((cc->sector_size >> SECTOR_SHIFT) - 1)) != 0))
3471		return DM_MAPIO_KILL;
3472
3473	if (unlikely(bio->bi_iter.bi_size & (cc->sector_size - 1)))
3474		return DM_MAPIO_KILL;
3475
3476	io = dm_per_bio_data(bio, cc->per_bio_data_size);
3477	crypt_io_init(io, cc, bio, dm_target_offset(ti, bio->bi_iter.bi_sector));
3478
3479	if (cc->on_disk_tag_size) {
3480		unsigned int tag_len = cc->on_disk_tag_size * (bio_sectors(bio) >> cc->sector_shift);
3481
3482		if (unlikely(tag_len > KMALLOC_MAX_SIZE))
3483			io->integrity_metadata = NULL;
3484		else
3485			io->integrity_metadata = kmalloc(tag_len, GFP_NOIO | __GFP_NORETRY | __GFP_NOMEMALLOC | __GFP_NOWARN);
3486
3487		if (unlikely(!io->integrity_metadata)) {
3488			if (bio_sectors(bio) > cc->tag_pool_max_sectors)
3489				dm_accept_partial_bio(bio, cc->tag_pool_max_sectors);
3490			io->integrity_metadata = mempool_alloc(&cc->tag_pool, GFP_NOIO);
3491			io->integrity_metadata_from_pool = true;
3492		}
3493	}
3494
3495	if (crypt_integrity_aead(cc))
3496		io->ctx.r.req_aead = (struct aead_request *)(io + 1);
3497	else
3498		io->ctx.r.req = (struct skcipher_request *)(io + 1);
3499
3500	if (bio_data_dir(io->base_bio) == READ) {
3501		if (kcryptd_io_read(io, CRYPT_MAP_READ_GFP))
3502			kcryptd_queue_read(io);
3503	} else
3504		kcryptd_queue_crypt(io);
3505
3506	return DM_MAPIO_SUBMITTED;
3507}
3508
3509static char hex2asc(unsigned char c)
3510{
3511	return c + '0' + ((unsigned int)(9 - c) >> 4 & 0x27);
3512}
3513
3514static void crypt_status(struct dm_target *ti, status_type_t type,
3515			 unsigned int status_flags, char *result, unsigned int maxlen)
3516{
3517	struct crypt_config *cc = ti->private;
3518	unsigned int i, sz = 0;
3519	int num_feature_args = 0;
3520
3521	switch (type) {
3522	case STATUSTYPE_INFO:
3523		result[0] = '\0';
3524		break;
3525
3526	case STATUSTYPE_TABLE:
3527		DMEMIT("%s ", cc->cipher_string);
3528
3529		if (cc->key_size > 0) {
3530			if (cc->key_string)
3531				DMEMIT(":%u:%s", cc->key_size, cc->key_string);
3532			else {
3533				for (i = 0; i < cc->key_size; i++) {
3534					DMEMIT("%c%c", hex2asc(cc->key[i] >> 4),
3535					       hex2asc(cc->key[i] & 0xf));
3536				}
3537			}
3538		} else
3539			DMEMIT("-");
3540
3541		DMEMIT(" %llu %s %llu", (unsigned long long)cc->iv_offset,
3542				cc->dev->name, (unsigned long long)cc->start);
3543
3544		num_feature_args += !!ti->num_discard_bios;
3545		num_feature_args += test_bit(DM_CRYPT_SAME_CPU, &cc->flags);
3546		num_feature_args += test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags);
3547		num_feature_args += test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags);
3548		num_feature_args += test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags);
3549		num_feature_args += cc->sector_size != (1 << SECTOR_SHIFT);
3550		num_feature_args += test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags);
3551		if (cc->on_disk_tag_size)
3552			num_feature_args++;
3553		if (num_feature_args) {
3554			DMEMIT(" %d", num_feature_args);
3555			if (ti->num_discard_bios)
3556				DMEMIT(" allow_discards");
3557			if (test_bit(DM_CRYPT_SAME_CPU, &cc->flags))
3558				DMEMIT(" same_cpu_crypt");
3559			if (test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags))
3560				DMEMIT(" submit_from_crypt_cpus");
3561			if (test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags))
3562				DMEMIT(" no_read_workqueue");
3563			if (test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags))
3564				DMEMIT(" no_write_workqueue");
3565			if (cc->on_disk_tag_size)
3566				DMEMIT(" integrity:%u:%s", cc->on_disk_tag_size, cc->cipher_auth);
3567			if (cc->sector_size != (1 << SECTOR_SHIFT))
3568				DMEMIT(" sector_size:%d", cc->sector_size);
3569			if (test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags))
3570				DMEMIT(" iv_large_sectors");
3571		}
3572		break;
3573
3574	case STATUSTYPE_IMA:
3575		DMEMIT_TARGET_NAME_VERSION(ti->type);
3576		DMEMIT(",allow_discards=%c", ti->num_discard_bios ? 'y' : 'n');
3577		DMEMIT(",same_cpu_crypt=%c", test_bit(DM_CRYPT_SAME_CPU, &cc->flags) ? 'y' : 'n');
3578		DMEMIT(",submit_from_crypt_cpus=%c", test_bit(DM_CRYPT_NO_OFFLOAD, &cc->flags) ?
3579		       'y' : 'n');
3580		DMEMIT(",no_read_workqueue=%c", test_bit(DM_CRYPT_NO_READ_WORKQUEUE, &cc->flags) ?
3581		       'y' : 'n');
3582		DMEMIT(",no_write_workqueue=%c", test_bit(DM_CRYPT_NO_WRITE_WORKQUEUE, &cc->flags) ?
3583		       'y' : 'n');
3584		DMEMIT(",iv_large_sectors=%c", test_bit(CRYPT_IV_LARGE_SECTORS, &cc->cipher_flags) ?
3585		       'y' : 'n');
3586
3587		if (cc->on_disk_tag_size)
3588			DMEMIT(",integrity_tag_size=%u,cipher_auth=%s",
3589			       cc->on_disk_tag_size, cc->cipher_auth);
3590		if (cc->sector_size != (1 << SECTOR_SHIFT))
3591			DMEMIT(",sector_size=%d", cc->sector_size);
3592		if (cc->cipher_string)
3593			DMEMIT(",cipher_string=%s", cc->cipher_string);
3594
3595		DMEMIT(",key_size=%u", cc->key_size);
3596		DMEMIT(",key_parts=%u", cc->key_parts);
3597		DMEMIT(",key_extra_size=%u", cc->key_extra_size);
3598		DMEMIT(",key_mac_size=%u", cc->key_mac_size);
3599		DMEMIT(";");
3600		break;
3601	}
3602}
3603
3604static void crypt_postsuspend(struct dm_target *ti)
3605{
3606	struct crypt_config *cc = ti->private;
3607
3608	set_bit(DM_CRYPT_SUSPENDED, &cc->flags);
3609}
3610
3611static int crypt_preresume(struct dm_target *ti)
3612{
3613	struct crypt_config *cc = ti->private;
3614
3615	if (!test_bit(DM_CRYPT_KEY_VALID, &cc->flags)) {
3616		DMERR("aborting resume - crypt key is not set.");
3617		return -EAGAIN;
3618	}
3619
3620	return 0;
3621}
3622
3623static void crypt_resume(struct dm_target *ti)
3624{
3625	struct crypt_config *cc = ti->private;
3626
3627	clear_bit(DM_CRYPT_SUSPENDED, &cc->flags);
3628}
3629
3630/* Message interface
3631 *	key set <key>
3632 *	key wipe
3633 */
3634static int crypt_message(struct dm_target *ti, unsigned int argc, char **argv,
3635			 char *result, unsigned int maxlen)
3636{
3637	struct crypt_config *cc = ti->private;
3638	int key_size, ret = -EINVAL;
3639
3640	if (argc < 2)
3641		goto error;
3642
3643	if (!strcasecmp(argv[0], "key")) {
3644		if (!test_bit(DM_CRYPT_SUSPENDED, &cc->flags)) {
3645			DMWARN("not suspended during key manipulation.");
3646			return -EINVAL;
3647		}
3648		if (argc == 3 && !strcasecmp(argv[1], "set")) {
3649			/* The key size may not be changed. */
3650			key_size = get_key_size(&argv[2]);
3651			if (key_size < 0 || cc->key_size != key_size) {
3652				memset(argv[2], '0', strlen(argv[2]));
3653				return -EINVAL;
3654			}
3655
3656			ret = crypt_set_key(cc, argv[2]);
3657			if (ret)
3658				return ret;
3659			if (cc->iv_gen_ops && cc->iv_gen_ops->init)
3660				ret = cc->iv_gen_ops->init(cc);
3661			/* wipe the kernel key payload copy */
3662			if (cc->key_string)
3663				memset(cc->key, 0, cc->key_size * sizeof(u8));
3664			return ret;
3665		}
3666		if (argc == 2 && !strcasecmp(argv[1], "wipe"))
3667			return crypt_wipe_key(cc);
3668	}
3669
3670error:
3671	DMWARN("unrecognised message received.");
3672	return -EINVAL;
3673}
3674
3675static int crypt_iterate_devices(struct dm_target *ti,
3676				 iterate_devices_callout_fn fn, void *data)
3677{
3678	struct crypt_config *cc = ti->private;
3679
3680	return fn(ti, cc->dev, cc->start, ti->len, data);
3681}
3682
3683static void crypt_io_hints(struct dm_target *ti, struct queue_limits *limits)
3684{
3685	struct crypt_config *cc = ti->private;
3686
3687	/*
3688	 * Unfortunate constraint that is required to avoid the potential
3689	 * for exceeding underlying device's max_segments limits -- due to
3690	 * crypt_alloc_buffer() possibly allocating pages for the encryption
3691	 * bio that are not as physically contiguous as the original bio.
3692	 */
3693	limits->max_segment_size = PAGE_SIZE;
3694
3695	limits->logical_block_size =
3696		max_t(unsigned int, limits->logical_block_size, cc->sector_size);
3697	limits->physical_block_size =
3698		max_t(unsigned int, limits->physical_block_size, cc->sector_size);
3699	limits->io_min = max_t(unsigned int, limits->io_min, cc->sector_size);
3700	limits->dma_alignment = limits->logical_block_size - 1;
3701}
3702
3703static struct target_type crypt_target = {
3704	.name   = "crypt",
3705	.version = {1, 25, 0},
3706	.module = THIS_MODULE,
3707	.ctr    = crypt_ctr,
3708	.dtr    = crypt_dtr,
 
3709	.features = DM_TARGET_ZONED_HM,
3710	.report_zones = crypt_report_zones,
 
3711	.map    = crypt_map,
3712	.status = crypt_status,
3713	.postsuspend = crypt_postsuspend,
3714	.preresume = crypt_preresume,
3715	.resume = crypt_resume,
3716	.message = crypt_message,
3717	.iterate_devices = crypt_iterate_devices,
3718	.io_hints = crypt_io_hints,
3719};
3720module_dm(crypt);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
3721
3722MODULE_AUTHOR("Jana Saout <jana@saout.de>");
3723MODULE_DESCRIPTION(DM_NAME " target for transparent encryption / decryption");
3724MODULE_LICENSE("GPL");