/*

 * Copyright (c) 2013, Kenneth MacKay

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions are

 * met:

 *  * Redistributions of source code must retain the above copyright

 *   notice, this list of conditions and the following disclaimer.

 *  * 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.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * "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 COPYRIGHT

 * HOLDER 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.

 */

#include <stdbool.h>

#include <stdint.h>

/* Create a public key from a private key.

 *

 * Inputs:

 *	private_key - Your private key.

 *

 * Outputs:

 *	public_key  - Will be filled in with the public key.

 *

 * Returns true if the public key was generated successfully, false

 * if an error occurred. The keys are with the LSB first.

 */

bool ecc_make_public_key(const uint8_t private_key[32], uint8_t public_key[64]);

/* Create a public/private key pair.

 *

 * Outputs:

 *	public_key  - Will be filled in with the public key.

 *	private_key - Will be filled in with the private key.

 *

 * Returns true if the key pair was generated successfully, false

 * if an error occurred. The keys are with the LSB first.

 */

bool ecc_make_key(uint8_t public_key[64], uint8_t private_key[32]);

/* Check to see if a public key is valid.

 *

 * Inputs:

 *	public_key - The public key to check.

 *

 * Returns true if the public key is valid, false if it is invalid.

*/

bool ecc_valid_public_key(const uint8_t public_key[64]);

/* Compute a shared secret given your secret key and someone else's

 * public key.

 * Note: It is recommended that you hash the result of ecdh_shared_secret

 * before using it for symmetric encryption or HMAC.

 *

 * Inputs:

 *	public_key  - The public key of the remote party.

 *	private_key - Your private key.

 *

 * Outputs:

 *	secret - Will be filled in with the shared secret value.

 *

 * Returns true if the shared secret was generated successfully, false

 * if an error occurred. Both input and output parameters are with the

 * LSB first.

 */

bool ecdh_shared_secret(const uint8_t public_key[64],

				const uint8_t private_key[32],

				uint8_t secret[32]);