From 83c96cbc76604daccbc31cea9411555aea96fd6d Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Timo=20Ter=C3=A4s?= Date: Thu, 5 Feb 2015 09:16:51 +0200 Subject: [PATCH] crypto/hmac: support EVP_MD_CTX_FLAG_ONESHOT and set it properly Some engines (namely VIA C7 Padlock) work only if EVP_MD_CTX_FLAG_ONESHOT is set before final update. This is because some crypto accelerators cannot perform non-finalizing transform of the digest. The usage of EVP_MD_CTX_FLAG_ONESHOT is used semantically slightly differently here. It is set before the final EVP_DigestUpdate call, not necessarily before EVP_DigestInit call. This will not cause any problems though. --- crypto/hmac/hmac.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-) diff --git a/crypto/hmac/hmac.c b/crypto/hmac/hmac.c index 1fc9e2c..6f16578 100644 --- a/crypto/hmac/hmac.c +++ b/crypto/hmac/hmac.c @@ -109,7 +109,8 @@ int HMAC_Init_ex(HMAC_CTX *ctx, const void *key, int len, j = EVP_MD_block_size(md); OPENSSL_assert(j <= (int)sizeof(ctx->key)); if (j < len) { - if (!EVP_DigestInit_ex(&ctx->md_ctx, md, impl)) + EVP_MD_CTX_set_flags(&ctx->md_ctx, EVP_MD_CTX_FLAG_ONESHOT); + if (!EVP_DigestInit_ex(&ctx->md_ctx, md, impl)) goto err; if (!EVP_DigestUpdate(&ctx->md_ctx, key, len)) goto err; @@ -129,6 +130,7 @@ int HMAC_Init_ex(HMAC_CTX *ctx, const void *key, int len, if (reset) { for (i = 0; i < HMAC_MAX_MD_CBLOCK; i++) pad[i] = 0x36 ^ ctx->key[i]; + EVP_MD_CTX_clear_flags(&ctx->i_ctx, EVP_MD_CTX_FLAG_ONESHOT); if (!EVP_DigestInit_ex(&ctx->i_ctx, md, impl)) goto err; if (!EVP_DigestUpdate(&ctx->i_ctx, pad, EVP_MD_block_size(md))) @@ -136,6 +138,7 @@ int HMAC_Init_ex(HMAC_CTX *ctx, const void *key, int len, for (i = 0; i < HMAC_MAX_MD_CBLOCK; i++) pad[i] = 0x5c ^ ctx->key[i]; + EVP_MD_CTX_clear_flags(&ctx->o_ctx, EVP_MD_CTX_FLAG_ONESHOT); if (!EVP_DigestInit_ex(&ctx->o_ctx, md, impl)) goto err; if (!EVP_DigestUpdate(&ctx->o_ctx, pad, EVP_MD_block_size(md))) @@ -143,6 +146,7 @@ int HMAC_Init_ex(HMAC_CTX *ctx, const void *key, int len, } if (!EVP_MD_CTX_copy_ex(&ctx->md_ctx, &ctx->i_ctx)) goto err; + EVP_MD_CTX_clear_flags(&ctx->md_ctx, EVP_MD_CTX_FLAG_ONESHOT); return 1; err: return 0; @@ -177,6 +181,7 @@ int HMAC_Final(HMAC_CTX *ctx, unsigned char *md, unsigned int *len) goto err; if (!EVP_MD_CTX_copy_ex(&ctx->md_ctx, &ctx->o_ctx)) goto err; + EVP_MD_CTX_set_flags(&ctx->md_ctx,EVP_MD_CTX_FLAG_ONESHOT); if (!EVP_DigestUpdate(&ctx->md_ctx, buf, i)) goto err; if (!EVP_DigestFinal_ex(&ctx->md_ctx, md, len)) @@ -233,8 +238,9 @@ unsigned char *HMAC(const EVP_MD *evp_md, const void *key, int key_len, if (md == NULL) md = m; HMAC_CTX_init(&c); - if (!HMAC_Init(&c, key, key_len, evp_md)) + if (!HMAC_Init_ex(&c, key, key_len, evp_md, NULL)) goto err; + HMAC_CTX_set_flags(&c,EVP_MD_CTX_FLAG_ONESHOT); if (!HMAC_Update(&c, d, n)) goto err; if (!HMAC_Final(&c, md, md_len)) @@ -247,7 +253,7 @@ unsigned char *HMAC(const EVP_MD *evp_md, const void *key, int key_len, void HMAC_CTX_set_flags(HMAC_CTX *ctx, unsigned long flags) { - EVP_MD_CTX_set_flags(&ctx->i_ctx, flags); - EVP_MD_CTX_set_flags(&ctx->o_ctx, flags); + EVP_MD_CTX_set_flags(&ctx->i_ctx, flags & ~EVP_MD_CTX_FLAG_ONESHOT); + EVP_MD_CTX_set_flags(&ctx->o_ctx, flags & ~EVP_MD_CTX_FLAG_ONESHOT); EVP_MD_CTX_set_flags(&ctx->md_ctx, flags); } -- 2.2.2