/**
 * \file sha1.h
 *
 * \brief SHA-1 cryptographic hash function
 *
 *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
 *  SPDX-License-Identifier: Apache-2.0
 *
 *  Licensed under the Apache License, Version 2.0 (the "License"); you may
 *  not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *  This file is part of mbed TLS (https://tls.mbed.org) and was downloaded from
 *  https://github.com/Secure-Embedded-Systems/RSA-example/tree/master/include/.
 */
#ifndef SHA1_H
#define SHA1_H

#include <stddef.h>
#include <stdint.h>

#define SHA_DIGEST_LENGTH 20

#ifdef __cplusplus
extern "C" {
#endif

/**
 * \brief          SHA-1 context structure
 */
typedef struct {
  uint32_t total[2];  /*!< number of bytes processed  */
  uint32_t state[5];  /*!< intermediate digest state  */
  uint8_t buffer[64]; /*!< data block being processed */
} sha1_context;

/**
 * \brief          Initialize SHA-1 context
 *
 * \param ctx      SHA-1 context to be initialized
 */
void sha1_init(sha1_context *ctx);

/**
 * \brief          Clear SHA-1 context
 *
 * \param ctx      SHA-1 context to be cleared
 */
void sha1_free(sha1_context *ctx);

/**
 * \brief          Clone (the state of) a SHA-1 context
 *
 * \param dst      The destination context
 * \param src      The context to be cloned
 */
void sha1_clone(sha1_context *dst, const sha1_context *src);

/**
 * \brief          SHA-1 context setup
 *
 * \param ctx      context to be initialized
 */
void sha1_starts(sha1_context *ctx);

/**
 * \brief          SHA-1 process buffer
 *
 * \param ctx      SHA-1 context
 * \param input    buffer holding the  data
 * \param ilen     length of the input data
 */
void sha1_update(sha1_context *ctx, const uint8_t *input, size_t ilen);

/**
 * \brief          SHA-1 final digest
 *
 * \param ctx      SHA-1 context
 * \param output   SHA-1 checksum result
 */
void sha1_finish(sha1_context *ctx, uint8_t output[SHA_DIGEST_LENGTH]);

/* Internal use */
void sha1_process(sha1_context *ctx, const uint8_t data[64]);

/**
 * \brief          Output = SHA-1( input buffer )
 *
 * \param input    buffer holding the  data
 * \param ilen     length of the input data
 * \param output   SHA-1 checksum result
 */
void sha1(const uint8_t *input, size_t ilen, uint8_t output[SHA_DIGEST_LENGTH]);

#ifdef __cplusplus
}
#endif

#endif /* sha1.h */