Currently, the IV generation algorithms are implemented in dm-crypt.c. This patch implement these algorithms as template ciphers, so that dm-crypt layer can be simplified, and also these algorithms can be implemented in hardware for performance. Synchronous crypto requests to encrypt/decrypt a sector are processed sequentially. Asynchronous requests if processed in paralled, are freed in the async callback. Interface to the crypto layer - include/crypto/geniv.h This patch is based on the patchset originally started by Binoy Jayan <binoy.jayan@xxxxxxxxxx> ( crypto: Add IV generation algorithms https://patchwork.kernel.org/patch/9803469/ ) Signed-off-by: Binoy Jayan <binoy.jayan@xxxxxxxxxx> Signed-off-by: Xiongfeng Wang <wangxiongfeng2@xxxxxxxxxx> --- crypto/Kconfig | 7 + crypto/Makefile | 1 + crypto/geniv.c | 2240 ++++++++++++++++++++++++++++++++++++++++++++++++ include/crypto/geniv.h | 47 + 4 files changed, 2295 insertions(+) create mode 100644 crypto/geniv.c create mode 100644 include/crypto/geniv.h diff --git a/crypto/Kconfig b/crypto/Kconfig index f3e40ac..98f025a 100644 --- a/crypto/Kconfig +++ b/crypto/Kconfig @@ -257,6 +257,13 @@ config CRYPTO_GLUE_HELPER_X86 config CRYPTO_ENGINE tristate +config CRYPTO_GENIV + tristate "IV Generator Template" + select CRYPTO_AEAD + select CRYPTO_BLKCIPHER + help + Support for IV generator template, so that dm-crypt can rely on it. + comment "Authenticated Encryption with Associated Data" config CRYPTO_CCM diff --git a/crypto/Makefile b/crypto/Makefile index 6d1d40e..1077d2f 100644 --- a/crypto/Makefile +++ b/crypto/Makefile @@ -23,6 +23,7 @@ crypto_blkcipher-y += skcipher.o obj-$(CONFIG_CRYPTO_BLKCIPHER2) += crypto_blkcipher.o obj-$(CONFIG_CRYPTO_SEQIV) += seqiv.o obj-$(CONFIG_CRYPTO_ECHAINIV) += echainiv.o +obj-$(CONFIG_CRYPTO_GENIV) += geniv.o crypto_hash-y += ahash.o crypto_hash-y += shash.o diff --git a/crypto/geniv.c b/crypto/geniv.c new file mode 100644 index 0000000..55d1212 --- /dev/null +++ b/crypto/geniv.c @@ -0,0 +1,2240 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * geniv.c - crypto template for generating IV + * + * Copyright (C) 2018, Linaro + * + * This file adds a crypto template to generate IV, so the dm-crypt can rely + * on it and remove the existing generating IV code. + */ + +#include <linux/completion.h> +#include <linux/err.h> +#include <linux/module.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/key.h> +#include <linux/bio.h> +#include <linux/blkdev.h> +#include <linux/mempool.h> +#include <linux/slab.h> +#include <linux/crypto.h> +#include <linux/atomic.h> +#include <linux/scatterlist.h> +#include <linux/ctype.h> +#include <asm/page.h> +#include <asm/unaligned.h> +#include <crypto/hash.h> +#include <crypto/md5.h> +#include <crypto/algapi.h> +#include <crypto/skcipher.h> +#include <crypto/aead.h> +#include <crypto/authenc.h> +#include <crypto/geniv.h> +#include <crypto/internal/aead.h> +#include <crypto/internal/skcipher.h> +#include <linux/rtnetlink.h> /* for struct rtattr and RTA macros only */ +#include <keys/user-type.h> +#include <linux/backing-dev.h> +#include <linux/device-mapper.h> +#include <linux/log2.h> + +#define DM_MSG_PREFIX "crypt" +#define MIN_IOS 64 +#define IV_TYPE_NUM 8 +#define SECTOR_MASK ((1 << SECTOR_SHIFT) - 1) + +struct geniv_ctx; +struct geniv_req_ctx; + +/* Sub request for each of the skcipher_request's for a segment */ +struct geniv_subreq { + struct scatterlist sg_in[4]; + struct scatterlist sg_out[4]; + sector_t iv_sector; + struct geniv_req_ctx *rctx; + union { + struct skcipher_request req; + struct aead_request req_aead; + } r CRYPTO_MINALIGN_ATTR; +}; + +/* used to iter the src scatterlist of the input parent request */ +struct scatterlist_iter { + /* current segment to be processed */ + unsigned int seg_no; + /* bytes had been processed in current segment */ + unsigned int done; + /* bytes to be processed in the next request */ + unsigned int len; +}; + +/* contex of the input parent request */ +struct geniv_req_ctx { + struct geniv_subreq *subreq; + bool is_write; + bool is_aead_request; + sector_t cc_sector; + /* array size of src scatterlist of parent request */ + unsigned int nents; + struct scatterlist_iter iter; + struct completion restart; + atomic_t req_pending; + u8 *integrity_metadata; + /* point to the input parent request */ + union { + struct skcipher_request *req; + struct aead_request *req_aead; + } r; +}; + +struct crypt_iv_operations { + int (*ctr)(struct geniv_ctx *ctx); + void (*dtr)(struct geniv_ctx *ctx); + int (*init)(struct geniv_ctx *ctx); + int (*wipe)(struct geniv_ctx *ctx); + int (*generator)(struct geniv_ctx *ctx, + struct geniv_req_ctx *rctx, + struct geniv_subreq *subreq, u8 *iv); + int (*post)(struct geniv_ctx *ctx, + struct geniv_req_ctx *rctx, + struct geniv_subreq *subreq, u8 *iv); +}; + +struct geniv_essiv_private { + struct crypto_ahash *hash_tfm; + u8 *salt; +}; + +struct geniv_benbi_private { + int shift; +}; + +#define LMK_SEED_SIZE 64 /* hash + 0 */ +struct geniv_lmk_private { + struct crypto_shash *hash_tfm; + u8 *seed; +}; + +#define TCW_WHITENING_SIZE 16 +struct geniv_tcw_private { + struct crypto_shash *crc32_tfm; + u8 *iv_seed; + u8 *whitening; +}; + +/* context of geniv tfm */ +struct geniv_ctx { + unsigned int tfms_count; + union { + struct crypto_skcipher *tfm; + struct crypto_aead *tfm_aead; + } tfm_child; + union { + struct crypto_skcipher **tfms; + struct crypto_aead **tfms_aead; + } tfms; + + char *ivmode; + unsigned int iv_size; + unsigned int iv_start; + unsigned int rctx_start; + sector_t iv_offset; + unsigned short int sector_size; + unsigned char sector_shift; + char *algname; + char *ivopts; + char *cipher; + char *ciphermode; + unsigned long cipher_flags; + + const struct crypt_iv_operations *iv_gen_ops; + union { + struct geniv_essiv_private essiv; + struct geniv_benbi_private benbi; + struct geniv_lmk_private lmk; + struct geniv_tcw_private tcw; + } iv_gen_private; + void *iv_private; + + mempool_t *subreq_pool; + unsigned int key_size; + unsigned int key_parts; /* independent parts in key buffer */ + unsigned int key_extra_size; /* additional keys length */ + unsigned int key_mac_size; + + unsigned int integrity_tag_size; + unsigned int integrity_iv_size; + unsigned int on_disk_tag_size; + + char *msg; + u8 *authenc_key; /* space for keys in authenc() format (if used) */ + u8 *key; +}; + +static struct scatterlist *crypt_get_sg_data(struct geniv_ctx *ctx, + struct scatterlist *sg); + +static bool geniv_integrity_aead(struct geniv_ctx *ctx) +{ + return test_bit(CRYPT_MODE_INTEGRITY_AEAD, &ctx->cipher_flags); +} + +static bool geniv_integrity_hmac(struct geniv_ctx *ctx) +{ + return geniv_integrity_aead(ctx) && ctx->key_mac_size; +} + +static struct geniv_req_ctx *geniv_skcipher_req_ctx(struct skcipher_request *req) +{ + return (void *)PTR_ALIGN((u8 *)skcipher_request_ctx(req), __alignof__(struct geniv_req_ctx)); +} + +static struct geniv_req_ctx *geniv_aead_req_ctx(struct aead_request *req) +{ + return (void *)PTR_ALIGN((u8 *)aead_request_ctx(req), __alignof__(struct geniv_req_ctx)); +} + +static u8 *iv_of_subreq(struct geniv_ctx *ctx, struct geniv_subreq *subreq) +{ + if (geniv_integrity_aead(ctx)) + return (u8 *)ALIGN((unsigned long)((char *)subreq + ctx->iv_start), + crypto_aead_alignmask(crypto_aead_reqtfm(subreq->rctx->r.req_aead)) + 1); + else + return (u8 *)ALIGN((unsigned long)((char *)subreq + ctx->iv_start), + crypto_skcipher_alignmask(crypto_skcipher_reqtfm(subreq->rctx->r.req)) + 1); +} + +/* Get sg containing data */ +static struct scatterlist *crypt_get_sg_data(struct geniv_ctx *ctx, + struct scatterlist *sg) +{ + if (unlikely(geniv_integrity_aead(ctx))) + return &sg[2]; + + return sg; +} + +/* + * Different IV generation algorithms: + * + * plain: the initial vector is the 32-bit little-endian version of the sector + * number, padded with zeros if necessary. + * + * plain64: the initial vector is the 64-bit little-endian version of the sector + * number, padded with zeros if necessary. + * + * plain64be: the initial vector is the 64-bit big-endian version of the sector + * number, padded with zeros if necessary. + * + * essiv: "encrypted sector|salt initial vector", the sector number is + * encrypted with the bulk cipher using a salt as key. The salt + * should be derived from the bulk cipher's key via hashing. + * + * benbi: the 64-bit "big-endian 'narrow block'-count", starting at 1 + * (needed for LRW-32-AES and possible other narrow block modes) + * + * null: the initial vector is always zero. Provides compatibility with + * obsolete loop_fish2 devices. Do not use for new devices. + * + * lmk: Compatible implementation of the block chaining mode used + * by the Loop-AES block device encryption system + * designed by Jari Ruusu. See http://loop-aes.sourceforge.net/ + * It operates on full 512 byte sectors and uses CBC + * with an IV derived from the sector number, the data and + * optionally extra IV seed. + * This means that after decryption the first block + * of sector must be tweaked according to decrypted data. + * Loop-AES can use three encryption schemes: + * version 1: is plain aes-cbc mode + * version 2: uses 64 multikey scheme with lmk IV generator + * version 3: the same as version 2 with additional IV seed + * (it uses 65 keys, last key is used as IV seed) + * + * tcw: Compatible implementation of the block chaining mode used + * by the TrueCrypt device encryption system (prior to version 4.1). + * For more info see: https://gitlab.com/cryptsetup/cryptsetup/wikis/TrueCryptOnDiskFormat + * It operates on full 512 byte sectors and uses CBC + * with an IV derived from initial key and the sector number. + * In addition, whitening value is applied on every sector, whitening + * is calculated from initial key, sector number and mixed using CRC32. + * Note that this encryption scheme is vulnerable to watermarking attacks + * and should be used for old compatible containers access only. + * + * plumb: unimplemented, see: + * http://article.gmane.org/gmane.linux.kernel.device-mapper.dm-crypt/454 + */ + +static int crypt_iv_plain_gen(struct geniv_ctx *ctx, + struct geniv_req_ctx *rctx, + struct geniv_subreq *subreq, u8 *iv) +{ + memset(iv, 0, ctx->iv_size); + *(__le32 *)iv = cpu_to_le32(subreq->iv_sector & 0xffffffff); + + return 0; +} + +static int crypt_iv_plain64_gen(struct geniv_ctx *ctx, + struct geniv_req_ctx *rctx, + struct geniv_subreq *subreq, u8 *iv) +{ + memset(iv, 0, ctx->iv_size); + *(__le64 *)iv = cpu_to_le64(subreq->iv_sector); + + return 0; +} + +static int crypt_iv_plain64be_gen(struct geniv_ctx *ctx, + struct geniv_req_ctx *rctx, + struct geniv_subreq *subreq, u8 *iv) +{ + memset(iv, 0, ctx->iv_size); + /* iv_size is at least of size u64; usually it is 16 bytes */ + *(__be64 *)&iv[ctx->iv_size - sizeof(u64)] = cpu_to_be64(subreq->iv_sector); + + return 0; +} + +/* Initialise ESSIV - compute salt but no local memory allocations */ +static int crypt_iv_essiv_init(struct geniv_ctx *ctx) +{ + struct geniv_essiv_private *essiv = &ctx->iv_gen_private.essiv; + AHASH_REQUEST_ON_STACK(req, essiv->hash_tfm); + struct scatterlist sg; + struct crypto_cipher *essiv_tfm; + int err; + + sg_init_one(&sg, ctx->key, ctx->key_size); + ahash_request_set_tfm(req, essiv->hash_tfm); + ahash_request_set_callback(req, CRYPTO_TFM_REQ_MAY_SLEEP, NULL, NULL); + ahash_request_set_crypt(req, &sg, essiv->salt, ctx->key_size); + + err = crypto_ahash_digest(req); + ahash_request_zero(req); + if (err) + return err; + + essiv_tfm = ctx->iv_private; + + return crypto_cipher_setkey(essiv_tfm, essiv->salt, + crypto_ahash_digestsize(essiv->hash_tfm)); +} + +/* Wipe salt and reset key derived from volume key */ +static int crypt_iv_essiv_wipe(struct geniv_ctx *ctx) +{ + struct geniv_essiv_private *essiv = &ctx->iv_gen_private.essiv; + unsigned int salt_size = crypto_ahash_digestsize(essiv->hash_tfm); + struct crypto_cipher *essiv_tfm; + + memset(essiv->salt, 0, salt_size); + + essiv_tfm = ctx->iv_private; + return crypto_cipher_setkey(essiv_tfm, essiv->salt, salt_size); +} + +/* Allocate the cipher for ESSIV */ +static struct crypto_cipher *alloc_essiv_cipher(struct geniv_ctx *ctx, + u8 *salt, unsigned int saltsize) +{ + struct crypto_cipher *essiv_tfm; + int err; + + /* Setup the essiv_tfm with the given salt */ + essiv_tfm = crypto_alloc_cipher(ctx->cipher, 0, CRYPTO_ALG_ASYNC); + if (IS_ERR(essiv_tfm)) { + DMERR("Error allocating crypto tfm for ESSIV\n"); + return essiv_tfm; + } + + if (crypto_cipher_blocksize(essiv_tfm) != ctx->iv_size) { + DMERR("Block size of ESSIV cipher does " + "not match IV size of block cipher\n"); + crypto_free_cipher(essiv_tfm); + return ERR_PTR(-EINVAL); + } + + err = crypto_cipher_setkey(essiv_tfm, salt, saltsize); + if (err) { + DMERR("Failed to set key for ESSIV cipher\n"); + crypto_free_cipher(essiv_tfm); + return ERR_PTR(err); + } + + return essiv_tfm; +} + +static void crypt_iv_essiv_dtr(struct geniv_ctx *ctx) +{ + struct crypto_cipher *essiv_tfm; + struct geniv_essiv_private *essiv = &ctx->iv_gen_private.essiv; + + crypto_free_ahash(essiv->hash_tfm); + essiv->hash_tfm = NULL; + + kzfree(essiv->salt); + essiv->salt = NULL; + + essiv_tfm = ctx->iv_private; + + if (essiv_tfm) + crypto_free_cipher(essiv_tfm); + + ctx->iv_private = NULL; +} + +static int crypt_iv_essiv_ctr(struct geniv_ctx *ctx) +{ + struct crypto_cipher *essiv_tfm = NULL; + struct crypto_ahash *hash_tfm = NULL; + u8 *salt = NULL; + int err; + + if (!ctx->ivopts) { + DMERR("Digest algorithm missing for ESSIV mode\n"); + return -EINVAL; + } + + /* Allocate hash algorithm */ + hash_tfm = crypto_alloc_ahash(ctx->ivopts, 0, CRYPTO_ALG_ASYNC); + if (IS_ERR(hash_tfm)) { + DMERR("Error initializing ESSIV hash\n"); + err = PTR_ERR(hash_tfm); + goto bad; + } + + salt = kzalloc(crypto_ahash_digestsize(hash_tfm), GFP_KERNEL); + if (!salt) { + DMERR("Error kmallocing salt storage in ESSIV\n"); + err = -ENOMEM; + goto bad; + } + + ctx->iv_gen_private.essiv.salt = salt; + ctx->iv_gen_private.essiv.hash_tfm = hash_tfm; + + essiv_tfm = alloc_essiv_cipher(ctx, salt, + crypto_ahash_digestsize(hash_tfm)); + if (IS_ERR(essiv_tfm)) { + crypt_iv_essiv_dtr(ctx); + return PTR_ERR(essiv_tfm); + } + ctx->iv_private = essiv_tfm; + + return 0; + +bad: + if (hash_tfm && !IS_ERR(hash_tfm)) + crypto_free_ahash(hash_tfm); + kfree(salt); + return err; +} + +static int crypt_iv_essiv_gen(struct geniv_ctx *ctx, + struct geniv_req_ctx *rctx, + struct geniv_subreq *subreq, u8 *iv) +{ + struct crypto_cipher *essiv_tfm = ctx->iv_private; + + memset(iv, 0, ctx->iv_size); + *(__le64 *)iv = cpu_to_le64(subreq->iv_sector); + crypto_cipher_encrypt_one(essiv_tfm, iv, iv); + + return 0; +} + +static int crypt_iv_benbi_ctr(struct geniv_ctx *ctx) +{ + unsigned int bs = crypto_skcipher_blocksize(ctx->tfms.tfms[0]); + int log = ilog2(bs); + + /* we need to calculate how far we must shift the sector count + * to get the cipher block count, we use this shift in _gen */ + + if (1 << log != bs) { + DMERR("cypher blocksize is not a power of 2\n"); + return -EINVAL; + } + + if (log > 9) { + DMERR("cypher blocksize is > 512\n"); + return -EINVAL; + } + + ctx->iv_gen_private.benbi.shift = 9 - log; + + return 0; +} + +static void crypt_iv_benbi_dtr(struct geniv_ctx *ctx) +{ +} + +static int crypt_iv_benbi_gen(struct geniv_ctx *ctx, + struct geniv_req_ctx *rctx, + struct geniv_subreq *subreq, u8 *iv) +{ + __be64 val; + + memset(iv, 0, ctx->iv_size - sizeof(u64)); /* rest is cleared below */ + + val = cpu_to_be64(((u64)subreq->iv_sector << ctx->iv_gen_private.benbi.shift) + 1); + put_unaligned(val, (__be64 *)(iv + ctx->iv_size - sizeof(u64))); + + return 0; +} + +static int crypt_iv_null_gen(struct geniv_ctx *ctx, + struct geniv_req_ctx *rctx, + struct geniv_subreq *subreq, u8 *iv) +{ + memset(iv, 0, ctx->iv_size); + + return 0; +} + +static void crypt_iv_lmk_dtr(struct geniv_ctx *ctx) +{ + struct geniv_lmk_private *lmk = &ctx->iv_gen_private.lmk; + + if (lmk->hash_tfm && !IS_ERR(lmk->hash_tfm)) + crypto_free_shash(lmk->hash_tfm); + lmk->hash_tfm = NULL; + + kzfree(lmk->seed); + lmk->seed = NULL; +} + +static int crypt_iv_lmk_ctr(struct geniv_ctx *ctx) +{ + struct geniv_lmk_private *lmk = &ctx->iv_gen_private.lmk; + + if (ctx->sector_size != (1 << SECTOR_SHIFT)) { + DMERR("Unsupported sector size for LMK\n"); + return -EINVAL; + } + + lmk->hash_tfm = crypto_alloc_shash("md5", 0, 0); + if (IS_ERR(lmk->hash_tfm)) { + DMERR("Error initializing LMK hash, err=%ld\n", + PTR_ERR(lmk->hash_tfm)); + return PTR_ERR(lmk->hash_tfm); + } + + /* No seed in LMK version 2 */ + if (ctx->key_parts == ctx->tfms_count) { + lmk->seed = NULL; + return 0; + } + + lmk->seed = kzalloc(LMK_SEED_SIZE, GFP_KERNEL); + if (!lmk->seed) { + crypt_iv_lmk_dtr(ctx); + DMERR("Error kmallocing seed storage in LMK\n"); + return -ENOMEM; + } + + return 0; +} + +static int crypt_iv_lmk_init(struct geniv_ctx *ctx) +{ + struct geniv_lmk_private *lmk = &ctx->iv_gen_private.lmk; + int subkey_size = ctx->key_size / ctx->key_parts; + + /* LMK seed is on the position of LMK_KEYS + 1 key */ + if (lmk->seed) + memcpy(lmk->seed, ctx->key + (ctx->tfms_count * subkey_size), + crypto_shash_digestsize(lmk->hash_tfm)); + + return 0; +} + +static int crypt_iv_lmk_wipe(struct geniv_ctx *ctx) +{ + struct geniv_lmk_private *lmk = &ctx->iv_gen_private.lmk; + + if (lmk->seed) + memset(lmk->seed, 0, LMK_SEED_SIZE); + + return 0; +} + +static int crypt_iv_lmk_one(struct geniv_ctx *ctx, u8 *iv, + struct geniv_subreq *subreq, u8 *data) +{ + struct geniv_lmk_private *lmk = &ctx->iv_gen_private.lmk; + SHASH_DESC_ON_STACK(desc, lmk->hash_tfm); + struct md5_state md5state; + __le32 buf[4]; + int i, r; + + desc->tfm = lmk->hash_tfm; + desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP; + + r = crypto_shash_init(desc); + if (r) + return r; + + if (lmk->seed) { + r = crypto_shash_update(desc, lmk->seed, LMK_SEED_SIZE); + if (r) + return r; + } + + /* Sector is always 512B, block size 16, add data of blocks 1-31 */ + r = crypto_shash_update(desc, data + 16, 16 * 31); + if (r) + return r; + + /* Sector is cropped to 56 bits here */ + buf[0] = cpu_to_le32(subreq->iv_sector & 0xFFFFFFFF); + buf[1] = cpu_to_le32((((u64)subreq->iv_sector >> 32) & 0x00FFFFFF) | 0x80000000); + buf[2] = cpu_to_le32(4024); + buf[3] = 0; + r = crypto_shash_update(desc, (u8 *)buf, sizeof(buf)); + if (r) + return r; + + /* No MD5 padding here */ + r = crypto_shash_export(desc, &md5state); + if (r) + return r; + + for (i = 0; i < MD5_HASH_WORDS; i++) + __cpu_to_le32s(&md5state.hash[i]); + memcpy(iv, &md5state.hash, ctx->iv_size); + + return 0; +} + +static int crypt_iv_lmk_gen(struct geniv_ctx *ctx, + struct geniv_req_ctx *rctx, + struct geniv_subreq *subreq, u8 *iv) +{ + struct scatterlist *sg; + u8 *src; + int r = 0; + + if (rctx->is_write) { + sg = crypt_get_sg_data(ctx, subreq->sg_in); + src = kmap_atomic(sg_page(sg)); + r = crypt_iv_lmk_one(ctx, iv, subreq, src + sg->offset); + kunmap_atomic(src); + } else + memset(iv, 0, ctx->iv_size); + + return r; +} + +static int crypt_iv_lmk_post(struct geniv_ctx *ctx, + struct geniv_req_ctx *rctx, + struct geniv_subreq *subreq, u8 *iv) +{ + struct scatterlist *sg; + u8 *dst; + int r; + + if (rctx->is_write) + return 0; + + sg = crypt_get_sg_data(ctx, subreq->sg_out); + dst = kmap_atomic(sg_page(sg)); + r = crypt_iv_lmk_one(ctx, iv, subreq, dst + sg->offset); + + /* Tweak the first block of plaintext sector */ + if (!r) + crypto_xor(dst + sg->offset, iv, ctx->iv_size); + + kunmap_atomic(dst); + return r; +} + +static void crypt_iv_tcw_dtr(struct geniv_ctx *ctx) +{ + struct geniv_tcw_private *tcw = &ctx->iv_gen_private.tcw; + + kzfree(tcw->iv_seed); + tcw->iv_seed = NULL; + kzfree(tcw->whitening); + tcw->whitening = NULL; + + if (tcw->crc32_tfm && !IS_ERR(tcw->crc32_tfm)) + crypto_free_shash(tcw->crc32_tfm); + tcw->crc32_tfm = NULL; +} + +static int crypt_iv_tcw_ctr(struct geniv_ctx *ctx) +{ + struct geniv_tcw_private *tcw = &ctx->iv_gen_private.tcw; + + if (ctx->sector_size != (1 << SECTOR_SHIFT)) { + DMERR("Unsupported sector size for TCW\n"); + return -EINVAL; + } + + if (ctx->key_size <= (ctx->iv_size + TCW_WHITENING_SIZE)) { + DMERR("Wrong key size (%d) for TCW. Choose a value > %d bytes\n", + ctx->key_size, ctx->iv_size + TCW_WHITENING_SIZE); + return -EINVAL; + } + + tcw->crc32_tfm = crypto_alloc_shash("crc32", 0, 0); + if (IS_ERR(tcw->crc32_tfm)) { + DMERR("Error initializing CRC32 in TCW; err=%ld\n", + PTR_ERR(tcw->crc32_tfm)); + return PTR_ERR(tcw->crc32_tfm); + } + + tcw->iv_seed = kzalloc(ctx->iv_size, GFP_KERNEL); + tcw->whitening = kzalloc(TCW_WHITENING_SIZE, GFP_KERNEL); + if (!tcw->iv_seed || !tcw->whitening) { + crypt_iv_tcw_dtr(ctx); + DMERR("Error allocating seed storage in TCW\n"); + return -ENOMEM; + } + + return 0; +} + +static int crypt_iv_tcw_init(struct geniv_ctx *ctx) +{ + struct geniv_tcw_private *tcw = &ctx->iv_gen_private.tcw; + int key_offset = ctx->key_size - ctx->iv_size - TCW_WHITENING_SIZE; + + memcpy(tcw->iv_seed, &ctx->key[key_offset], ctx->iv_size); + memcpy(tcw->whitening, &ctx->key[key_offset + ctx->iv_size], + TCW_WHITENING_SIZE); + + return 0; +} + +static int crypt_iv_tcw_wipe(struct geniv_ctx *ctx) +{ + struct geniv_tcw_private *tcw = &ctx->iv_gen_private.tcw; + + memset(tcw->iv_seed, 0, ctx->iv_size); + memset(tcw->whitening, 0, TCW_WHITENING_SIZE); + + return 0; +} + +static int crypt_iv_tcw_whitening(struct geniv_ctx *ctx, + struct geniv_subreq *subreq, u8 *data) +{ + struct geniv_tcw_private *tcw = &ctx->iv_gen_private.tcw; + __le64 sector = cpu_to_le64(subreq->iv_sector); + u8 buf[TCW_WHITENING_SIZE]; + SHASH_DESC_ON_STACK(desc, tcw->crc32_tfm); + int i, r; + + /* xor whitening with sector number */ + crypto_xor_cpy(buf, tcw->whitening, (u8 *)§or, 8); + crypto_xor_cpy(&buf[8], tcw->whitening + 8, (u8 *)§or, 8); + + /* calculate crc32 for every 32bit part and xor it */ + desc->tfm = tcw->crc32_tfm; + desc->flags = CRYPTO_TFM_REQ_MAY_SLEEP; + for (i = 0; i < 4; i++) { + r = crypto_shash_init(desc); + if (r) + goto out; + r = crypto_shash_update(desc, &buf[i * 4], 4); + if (r) + goto out; + r = crypto_shash_final(desc, &buf[i * 4]); + if (r) + goto out; + } + crypto_xor(&buf[0], &buf[12], 4); + crypto_xor(&buf[4], &buf[8], 4); + + /* apply whitening (8 bytes) to whole sector */ + for (i = 0; i < ((1 << SECTOR_SHIFT) / 8); i++) + crypto_xor(data + i * 8, buf, 8); +out: + memzero_explicit(buf, sizeof(buf)); + return r; +} + +static int crypt_iv_tcw_gen(struct geniv_ctx *ctx, + struct geniv_req_ctx *rctx, + struct geniv_subreq *subreq, u8 *iv) +{ + struct scatterlist *sg; + struct geniv_tcw_private *tcw = &ctx->iv_gen_private.tcw; + __le64 sector = cpu_to_le64(subreq->iv_sector); + u8 *src; + int r = 0; + + /* Remove whitening from ciphertext */ + if (!rctx->is_write) { + sg = crypt_get_sg_data(ctx, subreq->sg_in); + src = kmap_atomic(sg_page(sg)); + r = crypt_iv_tcw_whitening(ctx, subreq, src + sg->offset); + kunmap_atomic(src); + } + + /* Calculate IV */ + crypto_xor_cpy(iv, tcw->iv_seed, (u8 *)§or, 8); + if (ctx->iv_size > 8) + crypto_xor_cpy(&iv[8], tcw->iv_seed + 8, (u8 *)§or, + ctx->iv_size - 8); + + return r; +} + +static int crypt_iv_tcw_post(struct geniv_ctx *ctx, + struct geniv_req_ctx *rctx, + struct geniv_subreq *subreq, u8 *iv) +{ + struct scatterlist *sg; + u8 *dst; + int r; + + if (!rctx->is_write) + return 0; + + /* Apply whitening on ciphertext */ + sg = crypt_get_sg_data(ctx, subreq->sg_out); + dst = kmap_atomic(sg_page(sg)); + r = crypt_iv_tcw_whitening(ctx, subreq, dst + sg->offset); + kunmap_atomic(dst); + + return r; +} + +static int crypt_iv_random_gen(struct geniv_ctx *ctx, + struct geniv_req_ctx *rctx, + struct geniv_subreq *subreq, u8 *iv) +{ + /* Used only for writes, there must be an additional space to store IV */ + get_random_bytes(iv, ctx->iv_size); + return 0; +} + +static const struct crypt_iv_operations crypt_iv_plain_ops = { + .generator = crypt_iv_plain_gen +}; + +static const struct crypt_iv_operations crypt_iv_plain64_ops = { + .generator = crypt_iv_plain64_gen +}; + +static const struct crypt_iv_operations crypt_iv_plain64be_ops = { + .generator = crypt_iv_plain64be_gen +}; + +static const struct crypt_iv_operations crypt_iv_essiv_ops = { + .ctr = crypt_iv_essiv_ctr, + .dtr = crypt_iv_essiv_dtr, + .init = crypt_iv_essiv_init, + .wipe = crypt_iv_essiv_wipe, + .generator = crypt_iv_essiv_gen +}; + +static const struct crypt_iv_operations crypt_iv_benbi_ops = { + .ctr = crypt_iv_benbi_ctr, + .dtr = crypt_iv_benbi_dtr, + .generator = crypt_iv_benbi_gen +}; + +static const struct crypt_iv_operations crypt_iv_null_ops = { + .generator = crypt_iv_null_gen +}; + +static const struct crypt_iv_operations crypt_iv_lmk_ops = { + .ctr = crypt_iv_lmk_ctr, + .dtr = crypt_iv_lmk_dtr, + .init = crypt_iv_lmk_init, + .wipe = crypt_iv_lmk_wipe, + .generator = crypt_iv_lmk_gen, + .post = crypt_iv_lmk_post +}; + +static const struct crypt_iv_operations crypt_iv_tcw_ops = { + .ctr = crypt_iv_tcw_ctr, + .dtr = crypt_iv_tcw_dtr, + .init = crypt_iv_tcw_init, + .wipe = crypt_iv_tcw_wipe, + .generator = crypt_iv_tcw_gen, + .post = crypt_iv_tcw_post +}; + +static struct crypt_iv_operations crypt_iv_random_ops = { + .generator = crypt_iv_random_gen +}; + +static int geniv_init_iv(struct geniv_ctx *ctx) +{ + int ret; + + DMDEBUG("IV Generation algorithm : %s\n", ctx->ivmode); + + if (ctx->ivmode == NULL) + ctx->iv_gen_ops = NULL; + else if (strcmp(ctx->ivmode, "plain") == 0) + ctx->iv_gen_ops = &crypt_iv_plain_ops; + else if (strcmp(ctx->ivmode, "plain64") == 0) + ctx->iv_gen_ops = &crypt_iv_plain64_ops; + else if (strcmp(ctx->ivmode, "essiv") == 0) + ctx->iv_gen_ops = &crypt_iv_essiv_ops; + else if (strcmp(ctx->ivmode, "benbi") == 0) + ctx->iv_gen_ops = &crypt_iv_benbi_ops; + else if (strcmp(ctx->ivmode, "null") == 0) + ctx->iv_gen_ops = &crypt_iv_null_ops; + else if (strcmp(ctx->ivmode, "lmk") == 0) { + ctx->iv_gen_ops = &crypt_iv_lmk_ops; + /* + * Version 2 and 3 is recognised according + * to length of provided multi-key string. + * If present (version 3), last key is used as IV seed. + * All keys (including IV seed) are always the same size. + */ + if (ctx->key_size % ctx->key_parts) { + ctx->key_parts++; + ctx->key_extra_size = ctx->key_size / ctx->key_parts; + } + } else if (strcmp(ctx->ivmode, "tcw") == 0) { + ctx->iv_gen_ops = &crypt_iv_tcw_ops; + ctx->key_parts += 2; /* IV + whitening */ + ctx->key_extra_size = ctx->iv_size + TCW_WHITENING_SIZE; + } else if (strcmp(ctx->ivmode, "random") == 0) { + ctx->iv_gen_ops = &crypt_iv_random_ops; + /* Need storage space in integrity fields. */ + ctx->integrity_iv_size = ctx->iv_size; + } else { + DMERR("Invalid IV mode %s\n", ctx->ivmode); + return -EINVAL; + } + + /* Allocate IV */ + if (ctx->iv_gen_ops && ctx->iv_gen_ops->ctr) { + ret = ctx->iv_gen_ops->ctr(ctx); + if (ret < 0) { + DMERR("Error creating IV for %s\n", ctx->ivmode); + return ret; + } + } + + /* Initialize IV (set keys for ESSIV etc) */ + if (ctx->iv_gen_ops && ctx->iv_gen_ops->init) { + ret = ctx->iv_gen_ops->init(ctx); + if (ret < 0) { + DMERR("Error creating IV for %s\n", ctx->ivmode); + return ret; + } + } + + return 0; +} + +static void geniv_free_tfms_aead(struct geniv_ctx *ctx) +{ + if (!ctx->tfms.tfms_aead) + return; + + if (ctx->tfms.tfms_aead[0] && IS_ERR(ctx->tfms.tfms_aead[0])) { + crypto_free_aead(ctx->tfms.tfms_aead[0]); + ctx->tfms.tfms_aead[0] = NULL; + } + + kfree(ctx->tfms.tfms_aead); + ctx->tfms.tfms_aead = NULL; +} + +static void geniv_free_tfms_skcipher(struct geniv_ctx *ctx) +{ + unsigned int i; + + if (!ctx->tfms.tfms) + return; + + for (i = 0; i < ctx->tfms_count; i++) + if (ctx->tfms.tfms[i] && IS_ERR(ctx->tfms.tfms[i])) { + crypto_free_skcipher(ctx->tfms.tfms[i]); + ctx->tfms.tfms[i] = NULL; + } + + kfree(ctx->tfms.tfms); + ctx->tfms.tfms = NULL; +} + +static void geniv_free_tfms(struct geniv_ctx *ctx) +{ + if (geniv_integrity_aead(ctx)) + geniv_free_tfms_aead(ctx); + else + geniv_free_tfms_skcipher(ctx); +} + +static int geniv_alloc_tfms_aead(struct crypto_aead *parent, + struct geniv_ctx *ctx) +{ + unsigned int reqsize, align; + + ctx->tfms.tfms_aead = kcalloc(1, sizeof(struct crypto_aead *), + GFP_KERNEL); + if (!ctx->tfms.tfms_aead) + return -ENOMEM; + + /* First instance is already allocated in geniv_init_tfm */ + ctx->tfms.tfms_aead[0] = ctx->tfm_child.tfm_aead; + + /* Setup the current cipher's request structure */ + align = crypto_aead_alignmask(parent); + align &= ~(crypto_tfm_ctx_alignment() - 1); + reqsize = align + sizeof(struct geniv_req_ctx) + + crypto_aead_reqsize(ctx->tfms.tfms_aead[0]); + + crypto_aead_set_reqsize(parent, reqsize); + + return 0; +} + +/* Allocate memory for the underlying cipher algorithm. Ex: cbc(aes) + */ +static int geniv_alloc_tfms_skcipher(struct crypto_skcipher *parent, + struct geniv_ctx *ctx) +{ + unsigned int i, reqsize, align, err; + + ctx->tfms.tfms = kcalloc(ctx->tfms_count, sizeof(struct crypto_skcipher *), + GFP_KERNEL); + if (!ctx->tfms.tfms) + return -ENOMEM; + + /* First instance is already allocated in geniv_init_tfm */ + ctx->tfms.tfms[0] = ctx->tfm_child.tfm; + for (i = 1; i < ctx->tfms_count; i++) { + ctx->tfms.tfms[i] = crypto_alloc_skcipher(ctx->ciphermode, 0, 0); + if (IS_ERR(ctx->tfms.tfms[i])) { + err = PTR_ERR(ctx->tfms.tfms[i]); + geniv_free_tfms(ctx); + return err; + } + + /* Setup the current cipher's request structure */ + align = crypto_skcipher_alignmask(parent); + align &= ~(crypto_tfm_ctx_alignment() - 1); + reqsize = align + sizeof(struct geniv_req_ctx) + + crypto_skcipher_reqsize(ctx->tfms.tfms[i]); + + crypto_skcipher_set_reqsize(parent, reqsize); + } + + return 0; +} + +static unsigned int geniv_authenckey_size(struct geniv_ctx *ctx) +{ + return ctx->key_size - ctx->key_extra_size + + RTA_SPACE(sizeof(struct crypto_authenc_key_param)); +} + +/* Initialize the cipher's context with the key, ivmode and other parameters. + * Also allocate IV generation template ciphers and initialize them. + */ +static int geniv_setkey_init(void *parent, struct geniv_key_info *info) +{ + struct geniv_ctx *ctx; + int ret; + + if (test_bit(CRYPT_MODE_INTEGRITY_AEAD, &info->cipher_flags)) + ctx = crypto_aead_ctx((struct crypto_aead *)parent); + else + ctx = crypto_skcipher_ctx((struct crypto_skcipher *)parent); + + ctx->tfms_count = info->tfms_count; + ctx->key = info->key; + ctx->cipher_flags = info->cipher_flags; + ctx->ivopts = info->ivopts; + ctx->iv_offset = info->iv_offset; + ctx->sector_size = info->sector_size; + ctx->sector_shift = __ffs(ctx->sector_size) - SECTOR_SHIFT; + + ctx->key_size = info->key_size; + ctx->key_parts = info->key_parts; + ctx->key_mac_size = info->key_mac_size; + ctx->on_disk_tag_size = info->on_disk_tag_size; + + if (geniv_integrity_hmac(ctx)) { + ctx->authenc_key = kmalloc(geniv_authenckey_size(ctx), GFP_KERNEL); + if (!ctx->authenc_key) + return -ENOMEM; + } + + if (geniv_integrity_aead(ctx)) + ret = geniv_alloc_tfms_aead((struct crypto_aead *)parent, ctx); + else + ret = geniv_alloc_tfms_skcipher((struct crypto_skcipher *)parent, ctx); + if (ret) + return ret; + + ret = geniv_init_iv(ctx); + + if (geniv_integrity_aead(ctx)) + ctx->integrity_tag_size = ctx->on_disk_tag_size - ctx->integrity_iv_size; + + return ret; +} + +/* + * If AEAD is composed like authenc(hmac(sha256),xts(aes)), + * the key must be for some reason in special format. + * This function converts cc->key to this special format. + */ +static void crypt_copy_authenckey(char *p, const void *key, + unsigned int enckeylen, unsigned int authkeylen) +{ + struct crypto_authenc_key_param *param; + struct rtattr *rta; + + rta = (struct rtattr *)p; + param = RTA_DATA(rta); + param->enckeylen = cpu_to_be32(enckeylen); + rta->rta_len = RTA_LENGTH(sizeof(*param)); + rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; + p += RTA_SPACE(sizeof(*param)); + memcpy(p, key + enckeylen, authkeylen); + p += authkeylen; + memcpy(p, key, enckeylen); +} + +static int geniv_setkey_tfms_aead(struct crypto_aead *parent, struct geniv_ctx *ctx, + struct geniv_key_info *info) +{ + unsigned int key_size; + unsigned int authenc_key_size; + struct crypto_aead *child_aead; + int ret = 0; + + /* Ignore extra keys (which are used for IV etc) */ + key_size = ctx->key_size - ctx->key_extra_size; + authenc_key_size = key_size + RTA_SPACE(sizeof(struct crypto_authenc_key_param)); + + child_aead = ctx->tfms.tfms_aead[0]; + crypto_aead_clear_flags(child_aead, CRYPTO_TFM_REQ_MASK); + crypto_aead_set_flags(child_aead, crypto_aead_get_flags(parent) & CRYPTO_TFM_REQ_MASK); + + if (geniv_integrity_hmac(ctx)) { + if (key_size < ctx->key_mac_size) + return -EINVAL; + + crypt_copy_authenckey(ctx->authenc_key, ctx->key, key_size - ctx->key_mac_size, + ctx->key_mac_size); + } + + if (geniv_integrity_hmac(ctx)) + ret = crypto_aead_setkey(child_aead, ctx->authenc_key, authenc_key_size); + else + ret = crypto_aead_setkey(child_aead, ctx->key, key_size); + if (ret) { + DMERR("Error setting key for tfms[0]\n"); + goto out; + } + + crypto_aead_set_flags(parent, crypto_aead_get_flags(child_aead) & CRYPTO_TFM_RES_MASK); + +out: + if (geniv_integrity_hmac(ctx)) + memzero_explicit(ctx->authenc_key, authenc_key_size); + + return ret; +} + +static int geniv_setkey_tfms_skcipher(struct crypto_skcipher *parent, struct geniv_ctx *ctx, + struct geniv_key_info *info) +{ + unsigned int subkey_size; + char *subkey; + struct crypto_skcipher *child; + int ret, i; + + /* Ignore extra keys (which are used for IV etc) */ + subkey_size = (ctx->key_size - ctx->key_extra_size) + >> ilog2(ctx->tfms_count); + + for (i = 0; i < ctx->tfms_count; i++) { + child = ctx->tfms.tfms[i]; + crypto_skcipher_clear_flags(child, CRYPTO_TFM_REQ_MASK); + crypto_skcipher_set_flags(child, + crypto_skcipher_get_flags(parent) & CRYPTO_TFM_REQ_MASK); + + subkey = ctx->key + (subkey_size) * i; + + ret = crypto_skcipher_setkey(child, subkey, subkey_size); + if (ret) { + DMERR("Error setting key for tfms[%d]\n", i); + return ret; + } + + crypto_skcipher_set_flags(parent, crypto_skcipher_get_flags(child) & + CRYPTO_TFM_RES_MASK); + } + + return 0; +} + +static int geniv_setkey_set(struct geniv_ctx *ctx) +{ + if (ctx->iv_gen_ops && ctx->iv_gen_ops->init) + return ctx->iv_gen_ops->init(ctx); + else + return 0; +} + +static int geniv_setkey_wipe(struct geniv_ctx *ctx) +{ + int ret; + + if (ctx->iv_gen_ops && ctx->iv_gen_ops->wipe) { + ret = ctx->iv_gen_ops->wipe(ctx); + if (ret) + return ret; + } + + if (geniv_integrity_hmac(ctx)) + kzfree(ctx->authenc_key); + + return 0; +} + +static int geniv_setkey(void *parent, const u8 *key, unsigned int keylen) +{ + int err = 0; + struct geniv_ctx *ctx; + struct geniv_key_info *info = (struct geniv_key_info *) key; + + if (test_bit(CRYPT_MODE_INTEGRITY_AEAD, &info->cipher_flags)) + ctx = crypto_aead_ctx((struct crypto_aead *)parent); + else + ctx = crypto_skcipher_ctx((struct crypto_skcipher *)parent); + + DMDEBUG("SETKEY Operation : %d\n", info->keyop); + + switch (info->keyop) { + case SETKEY_OP_INIT: + err = geniv_setkey_init(parent, info); + break; + case SETKEY_OP_SET: + err = geniv_setkey_set(ctx); + break; + case SETKEY_OP_WIPE: + err = geniv_setkey_wipe(ctx); + break; + } + + if (err) + return err; + + if (test_bit(CRYPT_MODE_INTEGRITY_AEAD, &info->cipher_flags)) + return geniv_setkey_tfms_aead((struct crypto_aead *)parent, ctx, info); + else + return geniv_setkey_tfms_skcipher((struct crypto_skcipher *)parent, ctx, info); +} + +static int geniv_aead_setkey(struct crypto_aead *parent, + const u8 *key, unsigned int keylen) +{ + return geniv_setkey(parent, key, keylen); +} + +static int geniv_skcipher_setkey(struct crypto_skcipher *parent, + const u8 *key, unsigned int keylen) +{ + return geniv_setkey(parent, key, keylen); +} + +static void geniv_async_done(struct crypto_async_request *async_req, int error); + +static int geniv_alloc_subreq_aead(struct geniv_ctx *ctx, + struct geniv_req_ctx *rctx, + u32 req_flags) +{ + struct aead_request *req; + + if (!rctx->subreq) { + rctx->subreq = mempool_alloc(ctx->subreq_pool, GFP_NOIO); + if (!rctx->subreq) + return -ENOMEM; + } + + req = &rctx->subreq->r.req_aead; + rctx->subreq->rctx = rctx; + + aead_request_set_tfm(req, ctx->tfms.tfms_aead[0]); + aead_request_set_callback(req, req_flags, + geniv_async_done, rctx->subreq); + + return 0; +} + +/* req_flags: flags from parent request */ +static int geniv_alloc_subreq_skcipher(struct geniv_ctx *ctx, + struct geniv_req_ctx *rctx, + u32 req_flags) +{ + int key_index; + struct skcipher_request *req; + + if (!rctx->subreq) { + rctx->subreq = mempool_alloc(ctx->subreq_pool, GFP_NOIO); + if (!rctx->subreq) + return -ENOMEM; + } + + req = &rctx->subreq->r.req; + rctx->subreq->rctx = rctx; + + key_index = rctx->cc_sector & (ctx->tfms_count - 1); + + skcipher_request_set_tfm(req, ctx->tfms.tfms[key_index]); + skcipher_request_set_callback(req, req_flags, + geniv_async_done, rctx->subreq); + + return 0; +} + +/* Asynchronous IO completion callback for each sector in a segment. When all + * pending i/o are completed the parent cipher's async function is called. + */ +static void geniv_async_done(struct crypto_async_request *async_req, int error) +{ + struct geniv_subreq *subreq = + (struct geniv_subreq *) async_req->data; + struct geniv_req_ctx *rctx = subreq->rctx; + struct skcipher_request *req = NULL; + struct aead_request *req_aead = NULL; + struct geniv_ctx *ctx; + u8 *iv; + + if (!rctx->is_aead_request) { + req = rctx->r.req; + ctx = crypto_skcipher_ctx(crypto_skcipher_reqtfm(req)); + } else { + req_aead = rctx->r.req_aead; + ctx = crypto_aead_ctx(crypto_aead_reqtfm(req_aead)); + } + + /* + * A request from crypto driver backlog is going to be processed now, + * finish the completion and continue in crypt_convert(). + * (Callback will be called for the second time for this request.) + */ + if (error == -EINPROGRESS) { + complete(&rctx->restart); + return; + } + + iv = iv_of_subreq(ctx, subreq); + if (!error && ctx->iv_gen_ops && ctx->iv_gen_ops->post) + error = ctx->iv_gen_ops->post(ctx, rctx, subreq, iv); + + mempool_free(subreq, ctx->subreq_pool); + + /* req_pending needs to be checked before req->base.complete is called + * as we need 'req_pending' to be equal to 1 to ensure all subrequests + * are processed. + */ + if (atomic_dec_and_test(&rctx->req_pending)) { + /* Call the parent cipher's completion function */ + if (!rctx->is_aead_request) + skcipher_request_complete(req, error); + else + aead_request_complete(req_aead, error); + + } +} + +static unsigned int geniv_get_sectors(struct scatterlist *sg1, + struct scatterlist *sg2, + unsigned int segments) +{ + unsigned int i, n1, n2; + + n1 = n2 = 0; + for (i = 0; i < segments ; i++) { + n1 += sg1[i].length >> SECTOR_SHIFT; + n1 += (sg1[i].length & SECTOR_MASK) ? 1 : 0; + } + + for (i = 0; i < segments ; i++) { + n2 += sg2[i].length >> SECTOR_SHIFT; + n2 += (sg2[i].length & SECTOR_MASK) ? 1 : 0; + } + + return n1 > n2 ? n1 : n2; +} + +/* Iterate scatterlist of segments to retrieve the 512-byte sectors so that + * unique IVs could be generated for each 512-byte sector. This split may not + * be necessary e.g. when these ciphers are modelled in hardware, where it can + * make use of the hardware's IV generation capabilities. + */ +static int geniv_iter_block(void *req_in, + struct geniv_ctx *ctx, struct geniv_req_ctx *rctx) + +{ + unsigned int rem; + struct scatterlist *src_org, *dst_org; + struct scatterlist *src1, *dst1; + struct scatterlist_iter *iter = &rctx->iter; + struct skcipher_request *req; + struct aead_request *req_aead; + + if (unlikely(iter->seg_no >= rctx->nents)) + return 0; + + if (geniv_integrity_aead(ctx)) { + req_aead = (struct aead_request *)req_in; + src_org = &req_aead->src[0]; + dst_org = &req_aead->dst[0]; + } else { + req = (struct skcipher_request *)req_in; + src_org = &req->src[0]; + dst_org = &req->dst[0]; + } + + src1 = &src_org[iter->seg_no]; + dst1 = &dst_org[iter->seg_no]; + iter->done += iter->len; + + if (iter->done >= src1->length) { + iter->seg_no++; + + if (iter->seg_no >= rctx->nents) + return 0; + + src1 = &src_org[iter->seg_no]; + dst1 = &dst_org[iter->seg_no]; + iter->done = 0; + } + + rem = src1->length - iter->done; + + iter->len = rem > ctx->sector_size ? ctx->sector_size : rem; + + DMDEBUG("segment:(%d/%u), done:%d, rem:%d\n", + iter->seg_no, rctx->nents, iter->done, rem); + + return iter->len; +} + +static u8 *org_iv_of_subreq(struct geniv_ctx *ctx, struct geniv_subreq *subreq) +{ + return iv_of_subreq(ctx, subreq) + ctx->iv_size; +} + +static uint64_t *org_sector_of_subreq(struct geniv_ctx *ctx, struct geniv_subreq *subreq) +{ + u8 *ptr = iv_of_subreq(ctx, subreq) + ctx->iv_size + ctx->iv_size; + + return (uint64_t *) ptr; +} + +static unsigned int *org_tag_of_subreq(struct geniv_ctx *ctx, struct geniv_subreq *subreq) +{ + u8 *ptr = iv_of_subreq(ctx, subreq) + ctx->iv_size + + ctx->iv_size + sizeof(uint64_t); + + return (unsigned int *)ptr; +} + +static void *tag_from_subreq(struct geniv_ctx *ctx, struct geniv_subreq *subreq) +{ + return &subreq->rctx->integrity_metadata[*org_tag_of_subreq(ctx, subreq) * + ctx->on_disk_tag_size]; +} + +static void *iv_tag_from_subreq(struct geniv_ctx *ctx, struct geniv_subreq *subreq) +{ + return tag_from_subreq(ctx, subreq) + ctx->integrity_tag_size; +} + +static int geniv_convert_block_aead(struct geniv_ctx *ctx, + struct geniv_req_ctx *rctx, + struct geniv_subreq *subreq, + unsigned int tag_offset) +{ + struct scatterlist *sg_in, *sg_out; + u8 *iv, *org_iv, *tag_iv, *tag; + uint64_t *sector; + int r = 0; + struct scatterlist_iter *iter = &rctx->iter; + struct aead_request *req_aead; + struct aead_request *parent_req = rctx->r.req_aead; + + BUG_ON(ctx->integrity_iv_size && ctx->integrity_iv_size != ctx->iv_size); + + /* Reject unexpected unaligned bio. */ + if (unlikely(iter->len & (ctx->sector_size - 1))) + return -EIO; + + subreq->iv_sector = rctx->cc_sector; + if (test_bit(CRYPT_IV_LARGE_SECTORS, &ctx->cipher_flags)) + subreq->iv_sector >>= ctx->sector_shift; + + *org_tag_of_subreq(ctx, subreq) = tag_offset; + + sector = org_sector_of_subreq(ctx, subreq); + *sector = cpu_to_le64(rctx->cc_sector - ctx->iv_offset); + + iv = iv_of_subreq(ctx, subreq); + org_iv = org_iv_of_subreq(ctx, subreq); + tag = tag_from_subreq(ctx, subreq); + tag_iv = iv_tag_from_subreq(ctx, subreq); + + sg_in = subreq->sg_in; + sg_out = subreq->sg_out; + + /* AEAD request: + * |----- AAD -------|------ DATA -------|-- AUTH TAG --| + * | (authenticated) | (auth+encryption) | | + * | sector_LE | IV | sector in/out | tag in/out | + */ + sg_init_table(sg_in, 4); + sg_set_buf(&sg_in[0], sector, sizeof(uint64_t)); + sg_set_buf(&sg_in[1], org_iv, ctx->iv_size); + sg_set_page(&sg_in[2], sg_page(&parent_req->src[iter->seg_no]), + iter->len, parent_req->src[iter->seg_no].offset + iter->done); + sg_set_buf(&sg_in[3], tag, ctx->integrity_tag_size); + + sg_init_table(sg_out, 4); + sg_set_buf(&sg_out[0], sector, sizeof(uint64_t)); + sg_set_buf(&sg_out[1], org_iv, ctx->iv_size); + sg_set_page(&sg_out[2], sg_page(&parent_req->dst[iter->seg_no]), + iter->len, parent_req->dst[iter->seg_no].offset + iter->done); + sg_set_buf(&sg_out[3], tag, ctx->integrity_tag_size); + + if (ctx->iv_gen_ops) { + /* For READs use IV stored in integrity metadata */ + if (ctx->integrity_iv_size && !rctx->is_write) { + memcpy(org_iv, tag_iv, ctx->iv_size); + } else { + r = ctx->iv_gen_ops->generator(ctx, rctx, subreq, org_iv); + if (r < 0) + return r; + /* Store generated IV in integrity metadata */ + if (ctx->integrity_iv_size) + memcpy(tag_iv, org_iv, ctx->iv_size); + } + /* Working copy of IV, to be modified in crypto API */ + memcpy(iv, org_iv, ctx->iv_size); + } + + req_aead = &subreq->r.req_aead; + aead_request_set_ad(req_aead, sizeof(uint64_t) + ctx->iv_size); + if (rctx->is_write) { + aead_request_set_crypt(req_aead, subreq->sg_in, subreq->sg_out, + ctx->sector_size, iv); + r = crypto_aead_encrypt(req_aead); + if (ctx->integrity_tag_size + ctx->integrity_iv_size != ctx->on_disk_tag_size) + memset(tag + ctx->integrity_tag_size + ctx->integrity_iv_size, 0, + ctx->on_disk_tag_size - (ctx->integrity_tag_size + ctx->integrity_iv_size)); + } else { + aead_request_set_crypt(req_aead, subreq->sg_in, subreq->sg_out, + ctx->sector_size + ctx->integrity_tag_size, iv); + r = crypto_aead_decrypt(req_aead); + } + + if (r == -EBADMSG) + DMERR_LIMIT("INTEGRITY AEAD ERROR, sector %llu", + (unsigned long long)le64_to_cpu(*sector)); + + if (!r && ctx->iv_gen_ops && ctx->iv_gen_ops->post) + r = ctx->iv_gen_ops->post(ctx, rctx, subreq, org_iv); + + return r; +} + +static int geniv_convert_block_skcipher(struct geniv_ctx *ctx, + struct geniv_req_ctx *rctx, + struct geniv_subreq *subreq, + unsigned int tag_offset) +{ + struct scatterlist *sg_in, *sg_out; + u8 *iv, *org_iv, *tag_iv; + uint64_t *sector; + int r = 0; + struct scatterlist_iter *iter = &rctx->iter; + struct skcipher_request *req; + struct skcipher_request *parent_req = rctx->r.req; + + /* Reject unexpected unaligned bio. */ + if (unlikely(iter->len & (ctx->sector_size - 1))) + return -EIO; + + subreq->iv_sector = rctx->cc_sector; + if (test_bit(CRYPT_IV_LARGE_SECTORS, &ctx->cipher_flags)) + subreq->iv_sector >>= ctx->sector_shift; + + *org_tag_of_subreq(ctx, subreq) = tag_offset; + + iv = iv_of_subreq(ctx, subreq); + org_iv = org_iv_of_subreq(ctx, subreq); + tag_iv = iv_tag_from_subreq(ctx, subreq); + + sector = org_sector_of_subreq(ctx, subreq); + *sector = cpu_to_le64(rctx->cc_sector - ctx->iv_offset); + + /* For skcipher we use only the first sg item */ + sg_in = subreq->sg_in; + sg_out = subreq->sg_out; + + sg_init_table(sg_in, 1); + sg_set_page(sg_in, sg_page(&parent_req->src[iter->seg_no]), + iter->len, parent_req->src[iter->seg_no].offset + iter->done); + + sg_init_table(sg_out, 1); + sg_set_page(sg_out, sg_page(&parent_req->dst[iter->seg_no]), + iter->len, parent_req->dst[iter->seg_no].offset + iter->done); + + if (ctx->iv_gen_ops) { + /* For READs use IV stored in integrity metadata */ + if (ctx->integrity_iv_size && !rctx->is_write) { + memcpy(org_iv, tag_iv, ctx->integrity_iv_size); + } else { + r = ctx->iv_gen_ops->generator(ctx, rctx, subreq, org_iv); + if (r < 0) + return r; + /* Store generated IV in integrity metadata */ + if (ctx->integrity_iv_size) + memcpy(tag_iv, org_iv, ctx->integrity_iv_size); + } + /* Working copy of IV, to be modified in crypto API */ + memcpy(iv, org_iv, ctx->iv_size); + } + + req = &subreq->r.req; + skcipher_request_set_crypt(req, sg_in, sg_out, ctx->sector_size, iv); + + if (rctx->is_write) + r = crypto_skcipher_encrypt(req); + else + r = crypto_skcipher_decrypt(req); + + if (!r && ctx->iv_gen_ops && ctx->iv_gen_ops->post) + r = ctx->iv_gen_ops->post(ctx, rctx, subreq, org_iv); + + return r; +} + +/* Common encryt/decrypt function for geniv template cipher. Before the crypto + * operation, it splits the memory segments (in the scatterlist) into 512 byte + * sectors. The initialization vector(IV) used is based on a unique sector + * number which is generated here. + */ +static int geniv_crypt(struct geniv_ctx *ctx, void *parent_req, bool is_encrypt) +{ + struct skcipher_request *req = NULL; + struct aead_request *req_aead = NULL; + struct geniv_req_ctx *rctx; + struct geniv_req_info *rinfo; + int i, bytes, cryptlen, ret = 0; + unsigned int sectors; + unsigned int tag_offset = 0; + unsigned int sector_step = ctx->sector_size >> SECTOR_SHIFT; + char *str __maybe_unused = is_encrypt ? "encrypt" : "decrypt"; + + if (geniv_integrity_aead(ctx)) { + req_aead = (struct aead_request *)parent_req; + rctx = geniv_aead_req_ctx(req_aead); + rctx->r.req_aead = req_aead; + rinfo = (struct geniv_req_info *)req_aead->iv; + } else { + req = (struct skcipher_request *)parent_req; + rctx = geniv_skcipher_req_ctx(req); + rctx->r.req = req; + rinfo = (struct geniv_req_info *)req->iv; + } + + /* Instance of 'struct geniv_req_info' is stored in IV ptr */ + rctx->is_write = is_encrypt; + rctx->is_aead_request = geniv_integrity_aead(ctx); + rctx->cc_sector = rinfo->cc_sector; + rctx->nents = rinfo->nents; + rctx->integrity_metadata = rinfo->integrity_metadata; + rctx->subreq = NULL; + cryptlen = req->cryptlen; + + rctx->iter.seg_no = 0; + rctx->iter.done = 0; + rctx->iter.len = 0; + + DMDEBUG("geniv:%s: starting sector=%d, #segments=%u\n", str, + (unsigned int)rctx->cc_sector, rctx->nents); + + if (geniv_integrity_aead(ctx)) + sectors = geniv_get_sectors(req_aead->src, req_aead->dst, rctx->nents); + else + sectors = geniv_get_sectors(req->src, req->dst, rctx->nents); + + init_completion(&rctx->restart); + atomic_set(&rctx->req_pending, 1); + + for (i = 0; i < sectors; i++) { + struct geniv_subreq *subreq; + + if (geniv_integrity_aead(ctx)) + ret = geniv_alloc_subreq_aead(ctx, rctx, req_aead->base.flags); + else + ret = geniv_alloc_subreq_skcipher(ctx, rctx, req->base.flags); + if (ret) + return -ENOMEM; + + subreq = rctx->subreq; + + atomic_inc(&rctx->req_pending); + + if (geniv_integrity_aead(ctx)) + bytes = geniv_iter_block(req_aead, ctx, rctx); + else + bytes = geniv_iter_block(req, ctx, rctx); + + if (bytes == 0) + break; + + cryptlen -= bytes; + + if (geniv_integrity_aead(ctx)) + ret = geniv_convert_block_aead(ctx, rctx, subreq, tag_offset); + else + ret = geniv_convert_block_skcipher(ctx, rctx, subreq, tag_offset); + + switch (ret) { + /* + * The request was queued by a crypto driver + * but the driver request queue is full, let's wait. + */ + case -EBUSY: + wait_for_completion(&rctx->restart); + reinit_completion(&rctx->restart); + /* fall through */ + /* + * The request is queued and processed asynchronously, + * completion function geniv_async_done() is called. + */ + case -EINPROGRESS: + /* Marking this NULL lets the creation of a new sub- + * request when 'geniv_alloc_subreq' is called. + */ + rctx->subreq = NULL; + rctx->cc_sector += sector_step; + tag_offset++; + cond_resched(); + break; + /* + * The request was already processed (synchronously). + */ + case 0: + atomic_dec(&rctx->req_pending); + rctx->cc_sector += sector_step; + tag_offset++; + cond_resched(); + continue; + + /* There was an error while processing the request. */ + default: + atomic_dec(&rctx->req_pending); + mempool_free(rctx->subreq, ctx->subreq_pool); + atomic_dec(&rctx->req_pending); + return ret; + } + } + + if (rctx->subreq) + mempool_free(rctx->subreq, ctx->subreq_pool); + + if (atomic_dec_and_test(&rctx->req_pending)) + return 0; + else + return -EINPROGRESS; +} + +static int geniv_skcipher_encrypt(struct skcipher_request *req) +{ + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct geniv_ctx *ctx = crypto_skcipher_ctx(tfm); + + return geniv_crypt(ctx, req, true); +} + +static int geniv_skcipher_decrypt(struct skcipher_request *req) +{ + struct crypto_skcipher *tfm = crypto_skcipher_reqtfm(req); + struct geniv_ctx *ctx = crypto_skcipher_ctx(tfm); + + return geniv_crypt(ctx, req, false); +} + +static int geniv_aead_encrypt(struct aead_request *req) +{ + struct crypto_aead *tfm = crypto_aead_reqtfm(req); + struct geniv_ctx *ctx = crypto_aead_ctx(tfm); + + return geniv_crypt(ctx, req, true); +} + +static int geniv_aead_decrypt(struct aead_request *req) +{ + struct crypto_aead *tfm = crypto_aead_reqtfm(req); + struct geniv_ctx *ctx = crypto_aead_ctx(tfm); + + return geniv_crypt(ctx, req, false); +} + +/* + * Workaround to parse cipher algorithm from crypto API spec. + * The ctx->cipher is currently used only in ESSIV. + * This should be probably done by crypto-api calls (once available...) + */ +static int geniv_blkdev_cipher(struct geniv_ctx *ctx, bool is_crypto_aead) +{ + const char *alg_name = NULL; + char *start, *end; + + alg_name = ctx->ciphermode; + if (!alg_name) + return -EINVAL; + + if (is_crypto_aead) { + alg_name = strchr(alg_name, ','); + if (!alg_name) + alg_name = ctx->ciphermode; + alg_name++; + } + + start = strchr(alg_name, '('); + end = strchr(alg_name, ')'); + + if (!start && !end) { + ctx->cipher = kstrdup(alg_name, GFP_KERNEL); + return ctx->cipher ? 0 : -ENOMEM; + } + + if (!start || !end || ++start >= end) + return -EINVAL; + + ctx->cipher = kzalloc(end - start + 1, GFP_KERNEL); + if (!ctx->cipher) + return -ENOMEM; + + strncpy(ctx->cipher, start, end - start); + + return 0; +} + +static int geniv_init_tfm(void *tfm_tmp, bool is_crypto_aead) +{ + struct geniv_ctx *ctx; + struct crypto_skcipher *tfm; + struct crypto_aead *tfm_aead; + unsigned int reqsize; + size_t iv_size_padding; + char *algname; + int psize, ret; + + if (is_crypto_aead) { + tfm_aead = (struct crypto_aead *)tfm_tmp; + ctx = crypto_aead_ctx(tfm_aead); + algname = (char *) crypto_tfm_alg_name(crypto_aead_tfm(tfm_aead)); + } else { + tfm = (struct crypto_skcipher *)tfm_tmp; + ctx = crypto_skcipher_ctx(tfm); + algname = (char *) crypto_tfm_alg_name(crypto_skcipher_tfm(tfm)); + } + + ctx->ciphermode = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL); + if (!ctx->ciphermode) + return -ENOMEM; + + ctx->algname = kmalloc(CRYPTO_MAX_ALG_NAME, GFP_KERNEL); + if (!ctx->algname) { + ret = -ENOMEM; + goto free_ciphermode; + } + + strlcpy(ctx->algname, algname, CRYPTO_MAX_ALG_NAME); + algname = ctx->algname; + + /* Parse the algorithm name 'ivmode(ciphermode)' */ + ctx->ivmode = strsep(&algname, "("); + strlcpy(ctx->ciphermode, algname, CRYPTO_MAX_ALG_NAME); + ctx->ciphermode[strlen(algname) - 1] = '\0'; + + DMDEBUG("ciphermode=%s, ivmode=%s\n", ctx->ciphermode, ctx->ivmode); + + /* + * Usually the underlying cipher instances are spawned here, but since + * the value of tfms_count (which is equal to the key_count) is not + * known yet, create only one instance and delay the creation of the + * rest of the instances of the underlying cipher 'cbc(aes)' until + * the setkey operation is invoked. + * The first instance created i.e. ctx->child will later be assigned as + * the 1st element in the array ctx->tfms. Creation of atleast one + * instance of the cipher is necessary to be created here to uncover + * any errors earlier than during the setkey operation later where the + * remaining instances are created. + */ + if (is_crypto_aead) + ctx->tfm_child.tfm_aead = crypto_alloc_aead(ctx->ciphermode, 0, 0); + else + ctx->tfm_child.tfm = crypto_alloc_skcipher(ctx->ciphermode, 0, 0); + if (IS_ERR(ctx->tfm_child.tfm)) { + ret = PTR_ERR(ctx->tfm_child.tfm); + DMERR("Failed to create cipher %s. err %d\n", + ctx->ciphermode, ret); + goto free_algname; + } + + /* Setup the current cipher's request structure */ + if (is_crypto_aead) { + reqsize = sizeof(struct geniv_req_ctx) + __alignof__(struct geniv_req_ctx); + crypto_aead_set_reqsize(tfm_aead, reqsize); + + ctx->iv_start = sizeof(struct geniv_subreq); + ctx->iv_start += crypto_aead_reqsize(ctx->tfm_child.tfm_aead); + + ctx->iv_size = crypto_aead_ivsize(tfm_aead); + } else { + reqsize = sizeof(struct geniv_req_ctx) + __alignof__(struct geniv_req_ctx); + crypto_skcipher_set_reqsize(tfm, reqsize); + + ctx->iv_start = sizeof(struct geniv_subreq); + ctx->iv_start += crypto_skcipher_reqsize(ctx->tfm_child.tfm); + + ctx->iv_size = crypto_skcipher_ivsize(tfm); + } + /* at least a 64 bit sector number should fit in our buffer */ + if (ctx->iv_size) + ctx->iv_size = max(ctx->iv_size, + (unsigned int)(sizeof(u64) / sizeof(u8))); + + if (is_crypto_aead) { + if (crypto_aead_alignmask(tfm_aead) < CRYPTO_MINALIGN) { + /* Allocate the padding exactly */ + iv_size_padding = -ctx->iv_start + & crypto_aead_alignmask(ctx->tfm_child.tfm_aead); + } else { + /* + * If the cipher requires greater alignment than kmalloc + * alignment, we don't know the exact position of the + * initialization vector. We must assume worst case. + */ + iv_size_padding = crypto_aead_alignmask(ctx->tfm_child.tfm_aead); + } + } else { + if (crypto_skcipher_alignmask(tfm) < CRYPTO_MINALIGN) { + iv_size_padding = -ctx->iv_start + & crypto_skcipher_alignmask(ctx->tfm_child.tfm); + } else { + iv_size_padding = crypto_skcipher_alignmask(ctx->tfm_child.tfm); + } + } + + /* create memory pool for sub-request structure + * ...| IV + padding | original IV | original sec. number | bio tag offset | + */ + psize = ctx->iv_start + iv_size_padding + ctx->iv_size + ctx->iv_size + + sizeof(uint64_t) + sizeof(unsigned int); + + ctx->subreq_pool = mempool_create_kmalloc_pool(MIN_IOS, psize); + if (!ctx->subreq_pool) { + ret = -ENOMEM; + DMERR("Could not allocate crypt sub-request mempool\n"); + goto free_tfm; + } + + ret = geniv_blkdev_cipher(ctx, is_crypto_aead); + if (ret < 0) { + ret = -ENOMEM; + DMERR("Cannot allocate cipher string\n"); + goto free_tfm; + } + + return 0; + +free_tfm: + if (is_crypto_aead) + crypto_free_aead(ctx->tfm_child.tfm_aead); + else + crypto_free_skcipher(ctx->tfm_child.tfm); +free_algname: + kfree(ctx->algname); +free_ciphermode: + kfree(ctx->ciphermode); + return ret; +} + +static int geniv_skcipher_init_tfm(struct crypto_skcipher *tfm) +{ + return geniv_init_tfm(tfm, 0); +} + +static int geniv_aead_init_tfm(struct crypto_aead *tfm) +{ + return geniv_init_tfm(tfm, 1); +} + +static void geniv_exit_tfm(struct geniv_ctx *ctx) +{ + if (ctx->iv_gen_ops && ctx->iv_gen_ops->dtr) + ctx->iv_gen_ops->dtr(ctx); + + mempool_destroy(ctx->subreq_pool); + geniv_free_tfms(ctx); + kzfree(ctx->ciphermode); + kzfree(ctx->algname); + kzfree(ctx->cipher); +} + +static void geniv_skcipher_exit_tfm(struct crypto_skcipher *tfm) +{ + struct geniv_ctx *ctx = crypto_skcipher_ctx(tfm); + + geniv_exit_tfm(ctx); +} + +static void geniv_aead_exit_tfm(struct crypto_aead *tfm) +{ + struct geniv_ctx *ctx = crypto_aead_ctx(tfm); + + geniv_exit_tfm(ctx); +} + +static void geniv_skcipher_free(struct skcipher_instance *inst) +{ + struct crypto_skcipher_spawn *spawn = skcipher_instance_ctx(inst); + + crypto_drop_skcipher(spawn); + kfree(inst); +} + +static void geniv_aead_free(struct aead_instance *inst) +{ + struct crypto_aead_spawn *spawn = aead_instance_ctx(inst); + + crypto_drop_aead(spawn); + kfree(inst); +} + +static int geniv_skcipher_create(struct crypto_template *tmpl, + struct rtattr **tb, char *algname) +{ + struct crypto_attr_type *algt; + struct skcipher_instance *inst; + struct skcipher_alg *alg; + struct crypto_skcipher_spawn *spawn; + const char *cipher_name; + int err; + + algt = crypto_get_attr_type(tb); + + cipher_name = crypto_attr_alg_name(tb[1]); + + if (IS_ERR(cipher_name)) + return PTR_ERR(cipher_name); + + inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); + if (!inst) + return -ENOMEM; + + spawn = skcipher_instance_ctx(inst); + + crypto_set_skcipher_spawn(spawn, skcipher_crypto_instance(inst)); + err = crypto_grab_skcipher(spawn, cipher_name, 0, + crypto_requires_sync(algt->type, + algt->mask)); + + if (err) + goto err_free_inst; + + alg = crypto_spawn_skcipher_alg(spawn); + + err = -EINVAL; + + /* Only support blocks of size which is of a power of 2 */ + if (!is_power_of_2(alg->base.cra_blocksize)) + goto err_drop_spawn; + + /* algname: essiv, base.cra_name: cbc(aes) */ + err = -ENAMETOOLONG; + if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", + algname, alg->base.cra_name) >= CRYPTO_MAX_ALG_NAME) + goto err_drop_spawn; + if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, + "%s(%s)", algname, alg->base.cra_driver_name) >= + CRYPTO_MAX_ALG_NAME) + goto err_drop_spawn; + + inst->alg.base.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER; + inst->alg.base.cra_priority = alg->base.cra_priority; + inst->alg.base.cra_blocksize = alg->base.cra_blocksize; + inst->alg.base.cra_alignmask = alg->base.cra_alignmask; + inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC; + inst->alg.ivsize = alg->base.cra_blocksize; + inst->alg.chunksize = crypto_skcipher_alg_chunksize(alg); + inst->alg.min_keysize = sizeof(struct geniv_key_info); + inst->alg.max_keysize = sizeof(struct geniv_key_info); + + inst->alg.setkey = geniv_skcipher_setkey; + inst->alg.encrypt = geniv_skcipher_encrypt; + inst->alg.decrypt = geniv_skcipher_decrypt; + + inst->alg.base.cra_ctxsize = sizeof(struct geniv_ctx); + + inst->alg.init = geniv_skcipher_init_tfm; + inst->alg.exit = geniv_skcipher_exit_tfm; + + inst->free = geniv_skcipher_free; + + err = skcipher_register_instance(tmpl, inst); + if (err) + goto err_drop_spawn; + +out: + return err; + +err_drop_spawn: + crypto_drop_skcipher(spawn); +err_free_inst: + kfree(inst); + goto out; +} + + +static int geniv_aead_create(struct crypto_template *tmpl, + struct rtattr **tb, char *algname) +{ + struct crypto_attr_type *algt; + struct aead_instance *inst; + struct aead_alg *alg; + struct crypto_aead_spawn *spawn; + const char *cipher_name; + int err; + + algt = crypto_get_attr_type(tb); + + cipher_name = crypto_attr_alg_name(tb[1]); + if (IS_ERR(cipher_name)) + return PTR_ERR(cipher_name); + + inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); + if (!inst) + return -ENOMEM; + + spawn = aead_instance_ctx(inst); + + crypto_set_aead_spawn(spawn, aead_crypto_instance(inst)); + err = crypto_grab_aead(spawn, cipher_name, 0, + crypto_requires_sync(algt->type, + algt->mask)); + if (err) + goto err_free_inst; + + alg = crypto_spawn_aead_alg(spawn); + + /* Only support blocks of size which is of a power of 2 */ + if (!is_power_of_2(alg->base.cra_blocksize)) { + err = -EINVAL; + goto err_drop_spawn; + } + + /* algname: essiv, base.cra_name: cbc(aes) */ + if (snprintf(inst->alg.base.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", + algname, alg->base.cra_name) >= CRYPTO_MAX_ALG_NAME) { + err = -ENAMETOOLONG; + goto err_drop_spawn; + } + + if (snprintf(inst->alg.base.cra_driver_name, CRYPTO_MAX_ALG_NAME, + "%s(%s)", algname, alg->base.cra_driver_name) >= + CRYPTO_MAX_ALG_NAME) { + err = -ENAMETOOLONG; + goto err_drop_spawn; + } + + inst->alg.base.cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER; + inst->alg.base.cra_priority = alg->base.cra_priority; + inst->alg.base.cra_blocksize = alg->base.cra_blocksize; + inst->alg.base.cra_alignmask = alg->base.cra_alignmask; + inst->alg.base.cra_flags = alg->base.cra_flags & CRYPTO_ALG_ASYNC; + inst->alg.ivsize = crypto_aead_alg_ivsize(alg); + inst->alg.chunksize = crypto_aead_alg_chunksize(alg); + inst->alg.maxauthsize = crypto_aead_alg_maxauthsize(alg); + + inst->alg.setkey = geniv_aead_setkey; + inst->alg.encrypt = geniv_aead_encrypt; + inst->alg.decrypt = geniv_aead_decrypt; + + inst->alg.base.cra_ctxsize = sizeof(struct geniv_ctx); + + inst->alg.init = geniv_aead_init_tfm; + inst->alg.exit = geniv_aead_exit_tfm; + + inst->free = geniv_aead_free; + + err = aead_register_instance(tmpl, inst); + if (err) + goto err_drop_spawn; + + return 0; + +err_drop_spawn: + crypto_drop_aead(spawn); +err_free_inst: + kfree(inst); + return err; +} + +static int geniv_create(struct crypto_template *tmpl, + struct rtattr **tb, char *algname) +{ + if (!crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SKCIPHER)) + return geniv_skcipher_create(tmpl, tb, algname); + else if (!crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_AEAD)) + return geniv_aead_create(tmpl, tb, algname); + else + return -EINVAL; +} + +static int geniv_template_create(struct crypto_template *tmpl, + struct rtattr **tb) +{ + return geniv_create(tmpl, tb, tmpl->name); +} + +#define DEFINE_CRYPTO_TEMPLATE(type) \ + { .name = type, \ + .create = geniv_template_create, \ + .module = THIS_MODULE, }, + +static struct crypto_template geniv_tmpl[IV_TYPE_NUM] = { + DEFINE_CRYPTO_TEMPLATE("plain") + DEFINE_CRYPTO_TEMPLATE("plain64") + DEFINE_CRYPTO_TEMPLATE("essiv") + DEFINE_CRYPTO_TEMPLATE("benbi") + DEFINE_CRYPTO_TEMPLATE("null") + DEFINE_CRYPTO_TEMPLATE("lmk") + DEFINE_CRYPTO_TEMPLATE("tcw") + DEFINE_CRYPTO_TEMPLATE("random") +}; + +static int __init geniv_init(void) +{ + return crypto_register_template_array(geniv_tmpl, IV_TYPE_NUM); +} + +static void __exit geniv_exit(void) +{ + crypto_unregister_template_array(geniv_tmpl, IV_TYPE_NUM); +} + +module_init(geniv_init); +module_exit(geniv_exit); + +MODULE_AUTHOR("Xiongfeng Wang <xiongfeng.wang@xxxxxxxxxx>"); +MODULE_DESCRIPTION(DM_NAME " IV Generation Template "); +MODULE_LICENSE("GPL"); diff --git a/include/crypto/geniv.h b/include/crypto/geniv.h new file mode 100644 index 0000000..d8084fc --- /dev/null +++ b/include/crypto/geniv.h @@ -0,0 +1,47 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* + * geniv.h: common interface for IV generation algorithms + * + * Copyright (C) 2018, Linaro + * + * This file define the data structure the user should pass to the template. + */ + +#ifndef _CRYPTO_GENIV_H +#define _CRYPTO_GENIV_H + +#include <linux/types.h> + +enum cipher_flags { + CRYPT_MODE_INTEGRITY_AEAD, /* Use authenticated mode for cihper */ + CRYPT_IV_LARGE_SECTORS, /* Calculate IV from sector_size, not 512B sectors */ +}; + +enum setkey_op { + SETKEY_OP_INIT, + SETKEY_OP_SET, + SETKEY_OP_WIPE, +}; + +struct geniv_key_info { + enum setkey_op keyop; + unsigned int tfms_count; + u8 *key; + char *ivopts; + sector_t iv_offset; + unsigned long cipher_flags; + + unsigned short int sector_size; + unsigned int key_size; + unsigned int key_parts; + unsigned int key_mac_size; + unsigned int on_disk_tag_size; +}; + +struct geniv_req_info { + sector_t cc_sector; + unsigned int nents; + u8 *integrity_metadata; +}; + +#endif -- 1.7.12.4 -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel
