| // Copyright 2015 The Weave Authors. All rights reserved. | 
 | // Use of this source code is governed by a BSD-style license that can be | 
 | // found in the LICENSE file. | 
 |  | 
 | #ifndef LIBUWEAVE_SRC_CRYPTO_HMAC_H_ | 
 | #define LIBUWEAVE_SRC_CRYPTO_HMAC_H_ | 
 |  | 
 | #include <stdbool.h> | 
 | #include <stddef.h> | 
 | #include <stdint.h> | 
 |  | 
 | // Return the minimum required number of bytes for the state_buffer used in the | 
 | // init, update and final functions. | 
 | size_t uw_crypto_hmac_required_buffer_size_(); | 
 |  | 
 | bool uw_crypto_hmac_init_(uint8_t* state_buffer, | 
 |                           size_t state_buffer_len, | 
 |                           const uint8_t* key, | 
 |                           size_t key_len); | 
 | bool uw_crypto_hmac_update_(uint8_t* state_buffer, | 
 |                             size_t state_buffer_len, | 
 |                             const uint8_t* data, | 
 |                             size_t data_len); | 
 | bool uw_crypto_hmac_final_(uint8_t* state_buffer, | 
 |                            size_t state_buffer_len, | 
 |                            uint8_t* truncated_digest, | 
 |                            size_t truncated_digest_len); | 
 |  | 
 | #endif  // LIBUWEAVE_SRC_CRYPTO_HMAC_H_ |