text: /**
   * Copyright (c) 2013-2014 Tomas Dzetkulic
   * Copyright (c) 2013-2014 Pavol Rusnak
   *
   * Permission is hereby granted, free of charge, to any person obtaining
   * a copy of this software and associated documentation files (the "Software"),
   * to deal in the Software without restriction, including without limitation
   * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   * and/or sell copies of the Software, and to permit persons to whom the
   * Software is furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included
   * in all copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
   * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT HMAC_SHALL
   * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES
   * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
   * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
   * OTHER DEALINGS IN THE SOFTWARE.
   */
  
  #ifndef __HMAC_H__
  #define __HMAC_H__
  
  #include <stdint.h>
  #include <TrezorCrypto/sha2.h>
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  typedef struct _HMAC_SHA256_CTX {
    uint8_t o_key_pad[SHA256_BLOCK_LENGTH];
    SHA256_CTX ctx;
  } HMAC_SHA256_CTX;
  
  typedef struct _HMAC_SHA512_CTX {
    uint8_t o_key_pad[SHA512_BLOCK_LENGTH];
    SHA512_CTX ctx;
  } HMAC_SHA512_CTX;
  
  void hmac_sha256_Init(HMAC_SHA256_CTX *hctx, const uint8_t *key,
                        const uint32_t keylen);
  void hmac_sha256_Update(HMAC_SHA256_CTX *hctx, const uint8_t *msg,
                          const uint32_t msglen);
  void hmac_sha256_Final(HMAC_SHA256_CTX *hctx, uint8_t *hmac);
  void hmac_sha256(const uint8_t *key, const uint32_t keylen, const uint8_t *msg,
                   const uint32_t msglen, uint8_t *hmac);
  void hmac_sha256_prepare(const uint8_t *key, const uint32_t keylen,
                           uint32_t *opad_digest, uint32_t *ipad_digest);
  
  void hmac_sha512_Init(HMAC_SHA512_CTX *hctx, const uint8_t *key,
                        const uint32_t keylen);
  void hmac_sha512_Update(HMAC_SHA512_CTX *hctx, const uint8_t *msg,
                          const uint32_t msglen);
  void hmac_sha512_Final(HMAC_SHA512_CTX *hctx, uint8_t *hmac);
  void hmac_sha512(const uint8_t *key, const uint32_t keylen, const uint8_t *msg,
                   const uint32_t msglen, uint8_t *hmac);
  void hmac_sha512_prepare(const uint8_t *key, const uint32_t keylen,
                           uint64_t *opad_digest, uint64_t *ipad_digest);
  
  #ifdef __cplusplus
  } /* extern "C" */
  #endif
  
  #endif
  