/* * 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. */ #ifndef _CRYPTO_ECC_H #define _CRYPTO_ECC_H #define ECC_MAX_DIGITS 4 /* 256 */ #define ECC_DIGITS_TO_BYTES_SHIFT 3 /** * ecc_is_key_valid() - Validate a given ECDH private key * * @curve_id: id representing the curve to use * @ndigits: curve number of digits * @private_key: private key to be used for the given curve * @private_key_len: private key len * * Returns 0 if the key is acceptable, a negative value otherwise */ int ecc_is_key_valid(unsigned int curve_id, unsigned int ndigits, const u8 *private_key, unsigned int private_key_len); /** * ecdh_make_pub_key() - Compute an ECC public key * * @curve_id: id representing the curve to use * @private_key: pregenerated private key for the given curve * @private_key_len: length of private_key * @public_key: buffer for storing the public key generated * @public_key_len: length of the public_key buffer * * Returns 0 if the public key was generated successfully, a negative value * if an error occurred. */ int ecdh_make_pub_key(const unsigned int curve_id, unsigned int ndigits, const u8 *private_key, unsigned int private_key_len, u8 *public_key, unsigned int public_key_len); /** * crypto_ecdh_shared_secret() - Compute a shared secret * * @curve_id: id representing the curve to use * @private_key: private key of part A * @private_key_len: length of private_key * @public_key: public key of counterpart B * @public_key_len: length of public_key * @secret: buffer for storing the calculated shared secret * @secret_len: length of the secret buffer * * Note: It is recommended that you hash the result of crypto_ecdh_shared_secret * before using it for symmetric encryption or HMAC. * * Returns 0 if the shared secret was generated successfully, a negative value * if an error occurred. */ int crypto_ecdh_shared_secret(unsigned int curve_id, unsigned int ndigits, const u8 *private_key, unsigned int private_key_len, const u8 *public_key, unsigned int public_key_len, u8 *secret, unsigned int secret_len); #endif |