From 0b767b4df360bd442434d9d40b8a495e64202254 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Fri, 24 Jul 2009 15:18:41 +0800 Subject: [PATCH] crypto: hmac - Prehash ipad/opad This patch uses crypto_shash_export/crypto_shash_import to prehash ipad/opad to speed up hmac. This is partly based on a similar patch by Steffen Klassert. Signed-off-by: Herbert Xu --- crypto/hmac.c | 114 ++++++++++++++++++++++++++++---------------------- 1 file changed, 65 insertions(+), 49 deletions(-) diff --git a/crypto/hmac.c b/crypto/hmac.c index 02aa53ea14a..15c2eb53454 100644 --- a/crypto/hmac.c +++ b/crypto/hmac.c @@ -27,7 +27,7 @@ #include struct hmac_ctx { - struct shash_desc *desc; + struct crypto_shash *hash; }; static inline void *align_ptr(void *p, unsigned int align) @@ -38,8 +38,7 @@ static inline void *align_ptr(void *p, unsigned int align) static inline struct hmac_ctx *hmac_ctx(struct crypto_shash *tfm) { return align_ptr(crypto_shash_ctx_aligned(tfm) + - crypto_shash_blocksize(tfm) * 2 + - crypto_shash_digestsize(tfm), + crypto_shash_statesize(tfm) * 2, crypto_tfm_ctx_alignment()); } @@ -48,28 +47,33 @@ static int hmac_setkey(struct crypto_shash *parent, { int bs = crypto_shash_blocksize(parent); int ds = crypto_shash_digestsize(parent); + int ss = crypto_shash_statesize(parent); char *ipad = crypto_shash_ctx_aligned(parent); - char *opad = ipad + bs; - char *digest = opad + bs; - struct hmac_ctx *ctx = align_ptr(digest + ds, + char *opad = ipad + ss; + struct hmac_ctx *ctx = align_ptr(opad + ss, crypto_tfm_ctx_alignment()); + struct crypto_shash *hash = ctx->hash; + struct { + struct shash_desc shash; + char ctx[crypto_shash_descsize(hash)]; + } desc; unsigned int i; + desc.shash.tfm = hash; + desc.shash.flags = crypto_shash_get_flags(parent) & + CRYPTO_TFM_REQ_MAY_SLEEP; + if (keylen > bs) { int err; - ctx->desc->flags = crypto_shash_get_flags(parent) & - CRYPTO_TFM_REQ_MAY_SLEEP; - - err = crypto_shash_digest(ctx->desc, inkey, keylen, digest); + err = crypto_shash_digest(&desc.shash, inkey, keylen, ipad); if (err) return err; - inkey = digest; keylen = ds; - } + } else + memcpy(ipad, inkey, keylen); - memcpy(ipad, inkey, keylen); memset(ipad + keylen, 0, bs - keylen); memcpy(opad, ipad, bs); @@ -78,24 +82,37 @@ static int hmac_setkey(struct crypto_shash *parent, opad[i] ^= 0x5c; } - return 0; + return crypto_shash_init(&desc.shash) ?: + crypto_shash_update(&desc.shash, ipad, bs) ?: + crypto_shash_export(&desc.shash, ipad) ?: + crypto_shash_init(&desc.shash) ?: + crypto_shash_update(&desc.shash, opad, bs) ?: + crypto_shash_export(&desc.shash, opad); +} + +static int hmac_export(struct shash_desc *pdesc, void *out) +{ + struct shash_desc *desc = shash_desc_ctx(pdesc); + + desc->flags = pdesc->flags & CRYPTO_TFM_REQ_MAY_SLEEP; + + return crypto_shash_export(desc, out); +} + +static int hmac_import(struct shash_desc *pdesc, const void *in) +{ + struct shash_desc *desc = shash_desc_ctx(pdesc); + struct hmac_ctx *ctx = hmac_ctx(pdesc->tfm); + + desc->tfm = ctx->hash; + desc->flags = pdesc->flags & CRYPTO_TFM_REQ_MAY_SLEEP; + + return crypto_shash_import(desc, in); } static int hmac_init(struct shash_desc *pdesc) { - struct crypto_shash *parent = pdesc->tfm; - int bs = crypto_shash_blocksize(parent); - int ds = crypto_shash_digestsize(parent); - char *ipad = crypto_shash_ctx_aligned(parent); - struct hmac_ctx *ctx = align_ptr(ipad + bs * 2 + ds, - crypto_tfm_ctx_alignment()); - struct shash_desc *desc = shash_desc_ctx(pdesc); - - desc->tfm = ctx->desc->tfm; - desc->flags = pdesc->flags & CRYPTO_TFM_REQ_MAY_SLEEP; - - return crypto_shash_init(desc) ?: - crypto_shash_update(desc, ipad, bs); + return hmac_import(pdesc, crypto_shash_ctx_aligned(pdesc->tfm)); } static int hmac_update(struct shash_desc *pdesc, @@ -111,16 +128,16 @@ static int hmac_update(struct shash_desc *pdesc, static int hmac_final(struct shash_desc *pdesc, u8 *out) { struct crypto_shash *parent = pdesc->tfm; - int bs = crypto_shash_blocksize(parent); int ds = crypto_shash_digestsize(parent); - char *opad = crypto_shash_ctx_aligned(parent) + bs; - char *digest = opad + bs; + int ss = crypto_shash_statesize(parent); + char *opad = crypto_shash_ctx_aligned(parent) + ss; struct shash_desc *desc = shash_desc_ctx(pdesc); desc->flags = pdesc->flags & CRYPTO_TFM_REQ_MAY_SLEEP; - return crypto_shash_final(desc, digest) ?: - crypto_shash_digest(desc, opad, bs + ds, out); + return crypto_shash_final(desc, out) ?: + crypto_shash_import(desc, opad) ?: + crypto_shash_finup(desc, out, ds, out); } static int hmac_finup(struct shash_desc *pdesc, const u8 *data, @@ -128,16 +145,16 @@ static int hmac_finup(struct shash_desc *pdesc, const u8 *data, { struct crypto_shash *parent = pdesc->tfm; - int bs = crypto_shash_blocksize(parent); int ds = crypto_shash_digestsize(parent); - char *opad = crypto_shash_ctx_aligned(parent) + bs; - char *digest = opad + bs; + int ss = crypto_shash_statesize(parent); + char *opad = crypto_shash_ctx_aligned(parent) + ss; struct shash_desc *desc = shash_desc_ctx(pdesc); desc->flags = pdesc->flags & CRYPTO_TFM_REQ_MAY_SLEEP; - return crypto_shash_finup(desc, data, nbytes, digest) ?: - crypto_shash_digest(desc, opad, bs + ds, out); + return crypto_shash_finup(desc, data, nbytes, out) ?: + crypto_shash_import(desc, opad) ?: + crypto_shash_finup(desc, out, ds, out); } static int hmac_init_tfm(struct crypto_tfm *tfm) @@ -155,21 +172,14 @@ static int hmac_init_tfm(struct crypto_tfm *tfm) parent->descsize = sizeof(struct shash_desc) + crypto_shash_descsize(hash); - ctx->desc = kmalloc(parent->descsize, GFP_KERNEL); - if (!ctx->desc) { - crypto_free_shash(hash); - return -ENOMEM; - } - - ctx->desc->tfm = hash; + ctx->hash = hash; return 0; } static void hmac_exit_tfm(struct crypto_tfm *tfm) { struct hmac_ctx *ctx = hmac_ctx(__crypto_shash_cast(tfm)); - crypto_free_shash(ctx->desc->tfm); - kzfree(ctx->desc); + crypto_free_shash(ctx->hash); } static int hmac_create(struct crypto_template *tmpl, struct rtattr **tb) @@ -179,6 +189,7 @@ static int hmac_create(struct crypto_template *tmpl, struct rtattr **tb) struct shash_alg *salg; int err; int ds; + int ss; err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH); if (err) @@ -190,8 +201,10 @@ static int hmac_create(struct crypto_template *tmpl, struct rtattr **tb) err = -EINVAL; ds = salg->digestsize; + ss = salg->statesize; alg = &salg->base; - if (ds > alg->cra_blocksize) + if (ds > alg->cra_blocksize || + ss < alg->cra_blocksize) goto out_put_alg; inst = shash_alloc_instance("hmac", alg); @@ -208,11 +221,12 @@ static int hmac_create(struct crypto_template *tmpl, struct rtattr **tb) inst->alg.base.cra_blocksize = alg->cra_blocksize; inst->alg.base.cra_alignmask = alg->cra_alignmask; + ss = ALIGN(ss, alg->cra_alignmask + 1); inst->alg.digestsize = ds; + inst->alg.statesize = ss; inst->alg.base.cra_ctxsize = sizeof(struct hmac_ctx) + - ALIGN(alg->cra_blocksize * 2 + ds, - crypto_tfm_ctx_alignment()); + ALIGN(ss * 2, crypto_tfm_ctx_alignment()); inst->alg.base.cra_init = hmac_init_tfm; inst->alg.base.cra_exit = hmac_exit_tfm; @@ -221,6 +235,8 @@ static int hmac_create(struct crypto_template *tmpl, struct rtattr **tb) inst->alg.update = hmac_update; inst->alg.final = hmac_final; inst->alg.finup = hmac_finup; + inst->alg.export = hmac_export; + inst->alg.import = hmac_import; inst->alg.setkey = hmac_setkey; err = shash_register_instance(tmpl, inst);