| /* |
| * 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 |
