/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com) * All rights reserved. * * This package is an SSL implementation written * by Eric Young (eay@cryptsoft.com). * The implementation was written so as to conform with Netscapes SSL. * * This library is free for commercial and non-commercial use as long as * the following conditions are aheared to. The following conditions * apply to all code found in this distribution, be it the RC4, RSA, * lhash, DES, etc., code; not just the SSL code. The SSL documentation * included with this distribution is covered by the same copyright terms * except that the holder is Tim Hudson (tjh@cryptsoft.com). * * Copyright remains Eric Young's, and as such any Copyright notices in * the code are not to be removed. * If this package is used in a product, Eric Young should be given attribution * as the author of the parts of the library used. * This can be in the form of a textual message at program startup or * in documentation (online or textual) provided with the package. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * "This product includes cryptographic software written by * Eric Young (eay@cryptsoft.com)" * The word 'cryptographic' can be left out if the rouines from the library * being used are not cryptographic related :-). * 4. If you include any Windows specific code (or a derivative thereof) from * the apps directory (application code) you must include an acknowledgement: * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)" * * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * The licence and distribution terms for any publically available version or * derivative of this code cannot be changed. i.e. this code cannot simply be * copied and put under another distribution licence * [including the GNU Public Licence.] */ #ifndef OPENSSL_HEADER_HMAC_H #define OPENSSL_HEADER_HMAC_H #include #include #if defined(__cplusplus) extern "C" { #endif /* HMAC contains functions for constructing PRFs from Merkle–Damgård hash * functions using HMAC. */ /* One-shot operation. */ /* HMAC calculates the HMAC of |data_len| bytes of |data|, using the given key * and hash function, and writes the result to |out|. On entry, |out| must * contain |EVP_MAX_MD_SIZE| bytes of space. The actual length of the result is * written to |*out_len|. It returns |out| or NULL on error. */ uint8_t *HMAC(const EVP_MD *evp_md, const void *key, size_t key_len, const uint8_t *data, size_t data_len, uint8_t *out, unsigned int *out_len); /* Incremental operation. */ /* HMAC_CTX_init initialises |ctx| for use in an HMAC operation. It's assumed * that HMAC_CTX objects will be allocated on the stack thus no allocation * function is provided. If needed, allocate |sizeof(HMAC_CTX)| and call * |HMAC_CTX_init| on it. */ void HMAC_CTX_init(HMAC_CTX *ctx); /* HMAC_CTX_cleanup frees data owned by |ctx|. */ void HMAC_CTX_cleanup(HMAC_CTX *ctx); /* HMAC_Init_ex sets up an initialised |HMAC_CTX| to use |md| as the hash * function and |key| as the key. Any of |md| or |key| can be NULL, in which * case the previous value will be used. It returns one on success or zero * otherwise. */ int HMAC_Init_ex(HMAC_CTX *ctx, const void *key, size_t key_len, const EVP_MD *md, ENGINE *impl); /* HMAC_Update hashes |data_len| bytes from |data| into the current HMAC * operation in |ctx|. It returns one on success and zero on error. */ int HMAC_Update(HMAC_CTX *ctx, const uint8_t *data, size_t data_len); /* HMAC_Final completes the HMAC operation in |ctx| and writes the result to * |out| and the sets |*out_len| to the length of the result. On entry, |out| * must contain at least |EVP_MAX_MD_SIZE| bytes of space. It returns one on * success or zero on error. */ int HMAC_Final(HMAC_CTX *ctx, uint8_t *out, unsigned int *out_len); /* Utility functions. */ /* HMAC_size returns the size, in bytes, of the HMAC that will be produced by * |ctx|. On entry, |ctx| must have been setup with |HMAC_Init_ex|. */ size_t HMAC_size(const HMAC_CTX *ctx); /* HMAC_CTX_copy sets |dest| equal to |src|. On entry, |dest| must have been * initialised by calling |HMAC_CTX_init|. It returns one on success and zero * on error. */ int HMAC_CTX_copy(HMAC_CTX *dest, const HMAC_CTX *src); /* HMAC_CTX_set_flags ORs |flags| into the flags of the underlying digests of * |ctx|, which must have been setup by a call to |HMAC_Init_ex|. See * |EVP_MD_CTX_set_flags|. * * TODO(fork): remove? */ void HMAC_CTX_set_flags(HMAC_CTX *ctx, unsigned long flags); /* Deprecated functions. */ int HMAC_Init(HMAC_CTX *ctx, const void *key, int key_len, const EVP_MD *md); /* Private functions */ #define HMAC_MAX_MD_CBLOCK 128 /* largest known is SHA512 */ struct hmac_ctx_st { const EVP_MD *md; EVP_MD_CTX md_ctx; EVP_MD_CTX i_ctx; EVP_MD_CTX o_ctx; unsigned int key_length; unsigned char key[HMAC_MAX_MD_CBLOCK]; } /* HMAC_CTX */; #if defined(__cplusplus) } /* extern C */ #endif #endif /* OPENSSL_HEADER_HMAC_H */