From 5962f8b66dd040ad89d55b58967ea2dec607f4d3 Mon Sep 17 00:00:00 2001 From: Jussi Kivilinna Date: Wed, 9 Nov 2011 16:26:41 +0200 Subject: [PATCH] crypto: serpent-sse2 - add xts support Patch adds XTS support for serpent-sse2 by using xts_crypt(). Patch has been tested with tcrypt and automated filesystem tests. Tcrypt benchmarks results (serpent-sse2/serpent_generic speed ratios): Intel Celeron T1600 (x86_64) (fam:6, model:15, step:13): size xts-enc xts-dec 16B 0.98x 1.00x 64B 1.00x 1.01x 256B 2.78x 2.75x 1024B 3.30x 3.26x 8192B 3.39x 3.30x AMD Phenom II 1055T (x86_64) (fam:16, model:10): size xts-enc xts-dec 16B 1.05x 1.02x 64B 1.04x 1.03x 256B 2.10x 2.05x 1024B 2.34x 2.35x 8192B 2.34x 2.40x Intel Atom N270 (i586): size xts-enc xts-dec 16B 0.95x 0.96x 64B 1.53x 1.50x 256B 1.72x 1.75x 1024B 1.88x 1.87x 8192B 1.86x 1.83x Signed-off-by: Jussi Kivilinna Signed-off-by: Herbert Xu --- arch/x86/crypto/serpent_sse2_glue.c | 180 +++++++++++++++++++++++++++- 1 file changed, 178 insertions(+), 2 deletions(-) diff --git a/arch/x86/crypto/serpent_sse2_glue.c b/arch/x86/crypto/serpent_sse2_glue.c index db318e5cb240..2dffc5ab883e 100644 --- a/arch/x86/crypto/serpent_sse2_glue.c +++ b/arch/x86/crypto/serpent_sse2_glue.c @@ -40,6 +40,7 @@ #include #include #include +#include #include #include #include @@ -50,6 +51,10 @@ #define HAS_LRW #endif +#if defined(CONFIG_CRYPTO_XTS) || defined(CONFIG_CRYPTO_XTS_MODULE) +#define HAS_XTS +#endif + struct async_serpent_ctx { struct cryptd_ablkcipher *cryptd_tfm; }; @@ -465,7 +470,7 @@ static struct crypto_alg blk_ctr_alg = { }, }; -#ifdef HAS_LRW +#if defined(HAS_LRW) || defined(HAS_XTS) struct crypt_priv { struct serpent_ctx *ctx; @@ -506,6 +511,10 @@ static void decrypt_callback(void *priv, u8 *srcdst, unsigned int nbytes) __serpent_decrypt(ctx->ctx, srcdst, srcdst); } +#endif + +#ifdef HAS_LRW + struct serpent_lrw_ctx { struct lrw_table_ctx lrw_table; struct serpent_ctx serpent_ctx; @@ -611,6 +620,114 @@ static struct crypto_alg blk_lrw_alg = { #endif +#ifdef HAS_XTS + +struct serpent_xts_ctx { + struct serpent_ctx tweak_ctx; + struct serpent_ctx crypt_ctx; +}; + +static int xts_serpent_setkey(struct crypto_tfm *tfm, const u8 *key, + unsigned int keylen) +{ + struct serpent_xts_ctx *ctx = crypto_tfm_ctx(tfm); + u32 *flags = &tfm->crt_flags; + int err; + + /* key consists of keys of equal size concatenated, therefore + * the length must be even + */ + if (keylen % 2) { + *flags |= CRYPTO_TFM_RES_BAD_KEY_LEN; + return -EINVAL; + } + + /* first half of xts-key is for crypt */ + err = __serpent_setkey(&ctx->crypt_ctx, key, keylen / 2); + if (err) + return err; + + /* second half of xts-key is for tweak */ + return __serpent_setkey(&ctx->tweak_ctx, key + keylen / 2, keylen / 2); +} + +static int xts_encrypt(struct blkcipher_desc *desc, struct scatterlist *dst, + struct scatterlist *src, unsigned int nbytes) +{ + struct serpent_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm); + be128 buf[SERPENT_PARALLEL_BLOCKS]; + struct crypt_priv crypt_ctx = { + .ctx = &ctx->crypt_ctx, + .fpu_enabled = false, + }; + struct xts_crypt_req req = { + .tbuf = buf, + .tbuflen = sizeof(buf), + + .tweak_ctx = &ctx->tweak_ctx, + .tweak_fn = XTS_TWEAK_CAST(__serpent_encrypt), + .crypt_ctx = &crypt_ctx, + .crypt_fn = encrypt_callback, + }; + int ret; + + ret = xts_crypt(desc, dst, src, nbytes, &req); + serpent_fpu_end(crypt_ctx.fpu_enabled); + + return ret; +} + +static int xts_decrypt(struct blkcipher_desc *desc, struct scatterlist *dst, + struct scatterlist *src, unsigned int nbytes) +{ + struct serpent_xts_ctx *ctx = crypto_blkcipher_ctx(desc->tfm); + be128 buf[SERPENT_PARALLEL_BLOCKS]; + struct crypt_priv crypt_ctx = { + .ctx = &ctx->crypt_ctx, + .fpu_enabled = false, + }; + struct xts_crypt_req req = { + .tbuf = buf, + .tbuflen = sizeof(buf), + + .tweak_ctx = &ctx->tweak_ctx, + .tweak_fn = XTS_TWEAK_CAST(__serpent_encrypt), + .crypt_ctx = &crypt_ctx, + .crypt_fn = decrypt_callback, + }; + int ret; + + ret = xts_crypt(desc, dst, src, nbytes, &req); + serpent_fpu_end(crypt_ctx.fpu_enabled); + + return ret; +} + +static struct crypto_alg blk_xts_alg = { + .cra_name = "__xts-serpent-sse2", + .cra_driver_name = "__driver-xts-serpent-sse2", + .cra_priority = 0, + .cra_flags = CRYPTO_ALG_TYPE_BLKCIPHER, + .cra_blocksize = SERPENT_BLOCK_SIZE, + .cra_ctxsize = sizeof(struct serpent_xts_ctx), + .cra_alignmask = 0, + .cra_type = &crypto_blkcipher_type, + .cra_module = THIS_MODULE, + .cra_list = LIST_HEAD_INIT(blk_xts_alg.cra_list), + .cra_u = { + .blkcipher = { + .min_keysize = SERPENT_MIN_KEY_SIZE * 2, + .max_keysize = SERPENT_MAX_KEY_SIZE * 2, + .ivsize = SERPENT_BLOCK_SIZE, + .setkey = xts_serpent_setkey, + .encrypt = xts_encrypt, + .decrypt = xts_decrypt, + }, + }, +}; + +#endif + static int ablk_set_key(struct crypto_ablkcipher *tfm, const u8 *key, unsigned int key_len) { @@ -851,6 +968,46 @@ static struct crypto_alg ablk_lrw_alg = { #endif +#ifdef HAS_XTS + +static int ablk_xts_init(struct crypto_tfm *tfm) +{ + struct cryptd_ablkcipher *cryptd_tfm; + + cryptd_tfm = cryptd_alloc_ablkcipher("__driver-xts-serpent-sse2", 0, 0); + if (IS_ERR(cryptd_tfm)) + return PTR_ERR(cryptd_tfm); + ablk_init_common(tfm, cryptd_tfm); + return 0; +} + +static struct crypto_alg ablk_xts_alg = { + .cra_name = "xts(serpent)", + .cra_driver_name = "xts-serpent-sse2", + .cra_priority = 400, + .cra_flags = CRYPTO_ALG_TYPE_ABLKCIPHER | CRYPTO_ALG_ASYNC, + .cra_blocksize = SERPENT_BLOCK_SIZE, + .cra_ctxsize = sizeof(struct async_serpent_ctx), + .cra_alignmask = 0, + .cra_type = &crypto_ablkcipher_type, + .cra_module = THIS_MODULE, + .cra_list = LIST_HEAD_INIT(ablk_xts_alg.cra_list), + .cra_init = ablk_xts_init, + .cra_exit = ablk_exit, + .cra_u = { + .ablkcipher = { + .min_keysize = SERPENT_MIN_KEY_SIZE * 2, + .max_keysize = SERPENT_MAX_KEY_SIZE * 2, + .ivsize = SERPENT_BLOCK_SIZE, + .setkey = ablk_set_key, + .encrypt = ablk_encrypt, + .decrypt = ablk_decrypt, + }, + }, +}; + +#endif + static int __init serpent_sse2_init(void) { int err; @@ -885,15 +1042,30 @@ static int __init serpent_sse2_init(void) err = crypto_register_alg(&ablk_lrw_alg); if (err) goto ablk_lrw_err; +#endif +#ifdef HAS_XTS + err = crypto_register_alg(&blk_xts_alg); + if (err) + goto blk_xts_err; + err = crypto_register_alg(&ablk_xts_alg); + if (err) + goto ablk_xts_err; #endif return err; +#ifdef HAS_XTS + crypto_unregister_alg(&ablk_xts_alg); +ablk_xts_err: + crypto_unregister_alg(&blk_xts_alg); +blk_xts_err: +#endif #ifdef HAS_LRW + crypto_unregister_alg(&ablk_lrw_alg); ablk_lrw_err: crypto_unregister_alg(&blk_lrw_alg); blk_lrw_err: - crypto_unregister_alg(&ablk_ctr_alg); #endif + crypto_unregister_alg(&ablk_ctr_alg); ablk_ctr_err: crypto_unregister_alg(&ablk_cbc_alg); ablk_cbc_err: @@ -910,6 +1082,10 @@ blk_ecb_err: static void __exit serpent_sse2_exit(void) { +#ifdef HAS_XTS + crypto_unregister_alg(&ablk_xts_alg); + crypto_unregister_alg(&blk_xts_alg); +#endif #ifdef HAS_LRW crypto_unregister_alg(&ablk_lrw_alg); crypto_unregister_alg(&blk_lrw_alg); -- 2.30.2