/*
   * 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.
   */
  
  /* 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(u8 public_key[64], u8 private_key[32]);
  
  /* 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 u8 public_key[64], const u8 private_key[32],
  		        u8 secret[32]);