Commit 2d28a42f authored by Shane Lontis's avatar Shane Lontis Committed by Pauli
Browse files

hmac_init cleanup and fix key zeroization issue 



Reviewed-by: default avatarMatthias St. Pierre <Matthias.St.Pierre@ncp-e.com>
Reviewed-by: default avatarPaul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/7092)
parent bfb10b97

crypto/hmac/hmac.c

+16 −17
Original line number Diff line number Diff line 
/*

 * Copyright 1995-2016 The OpenSSL Project Authors. All Rights Reserved.

 * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the OpenSSL license (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy
@@ -18,6 +18,7 @@ 
int HMAC_Init_ex(HMAC_CTX *ctx, const void *key, int len,

                 const EVP_MD *md, ENGINE *impl)

{

    int rv = 0;

    int i, j, reset = 0;

    unsigned char pad[HMAC_MAX_MD_CBLOCK];
@@ -38,15 +39,13 @@ int HMAC_Init_ex(HMAC_CTX *ctx, const void *key, int len, 
        reset = 1;

        j = EVP_MD_block_size(md);

        if (!ossl_assert(j <= (int)sizeof(ctx->key)))

            goto err;

            return 0;

        if (j < len) {

            if (!EVP_DigestInit_ex(ctx->md_ctx, md, impl))

                goto err;

            if (!EVP_DigestUpdate(ctx->md_ctx, key, len))

                goto err;

            if (!EVP_DigestFinal_ex(ctx->md_ctx, ctx->key,

            if (!EVP_DigestInit_ex(ctx->md_ctx, md, impl)

                    || !EVP_DigestUpdate(ctx->md_ctx, key, len)

                    || !EVP_DigestFinal_ex(ctx->md_ctx, ctx->key,

                                           &ctx->key_length))

                goto err;

                return 0;

        } else {

            if (len < 0 || len > (int)sizeof(ctx->key))

                return 0;
@@ -61,23 +60,23 @@ 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];

        if (!EVP_DigestInit_ex(ctx->i_ctx, md, impl))

            goto err;

        if (!EVP_DigestUpdate(ctx->i_ctx, pad, EVP_MD_block_size(md)))

        if (!EVP_DigestInit_ex(ctx->i_ctx, md, impl)

                || !EVP_DigestUpdate(ctx->i_ctx, pad, EVP_MD_block_size(md)))

            goto err;



        for (i = 0; i < HMAC_MAX_MD_CBLOCK; i++)

            pad[i] = 0x5c ^ ctx->key[i];

        if (!EVP_DigestInit_ex(ctx->o_ctx, md, impl))

            goto err;

        if (!EVP_DigestUpdate(ctx->o_ctx, pad, EVP_MD_block_size(md)))

        if (!EVP_DigestInit_ex(ctx->o_ctx, md, impl)

                || !EVP_DigestUpdate(ctx->o_ctx, pad, EVP_MD_block_size(md)))

            goto err;

    }

    if (!EVP_MD_CTX_copy_ex(ctx->md_ctx, ctx->i_ctx))

        goto err;

    return 1;

    rv = 1;

 err:

    return 0;

    if (reset)

        OPENSSL_cleanse(pad, sizeof(pad));

    return rv;

}



#if OPENSSL_API_COMPAT < 0x10100000L