[linux.git] / crypto / ecc.h

/*
 * 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's number of digits
 * @private_key:	private key to be used for the given curve
 * @private_key_len:	private key length
 *
 * Returns 0 if the key is acceptable, a negative value otherwise
 */
int ecc_is_key_valid(unsigned int curve_id, unsigned int ndigits,
		     const u64 *private_key, unsigned int private_key_len);

/**
 * ecc_gen_privkey() -  Generates an ECC private key.
 * The private key is a random integer in the range 0 < random < n, where n is a
 * prime that is the order of the cyclic subgroup generated by the distinguished
 * point G.
 * @curve_id:		id representing the curve to use
 * @ndigits:		curve number of digits
 * @private_key:	buffer for storing the generated private key
 *
 * Returns 0 if the private key was generated successfully, a negative value
 * if an error occurred.
 */
int ecc_gen_privkey(unsigned int curve_id, unsigned int ndigits, u64 *privkey);

/**
 * ecc_make_pub_key() - Compute an ECC public key
 *
 * @curve_id:		id representing the curve to use
 * @ndigits:		curve's number of digits
 * @private_key:	pregenerated private key for the given curve
 * @public_key:		buffer for storing the generated public key
 *
 * Returns 0 if the public key was generated successfully, a negative value
 * if an error occurred.
 */
int ecc_make_pub_key(const unsigned int curve_id, unsigned int ndigits,
		     const u64 *private_key, u64 *public_key);

/**
 * crypto_ecdh_shared_secret() - Compute a shared secret
 *
 * @curve_id:		id representing the curve to use
 * @ndigits:		curve's number of digits
 * @private_key:	private key of part A
 * @public_key:		public key of counterpart B
 * @secret:		buffer for storing the calculated shared secret
 *
 * 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 u64 *private_key, const u64 *public_key,
			      u64 *secret);
#endif
Commit	Line	Data
3c4b2390 SB	1	/*
	2	* Copyright (c) 2013, Kenneth MacKay
	3	* All rights reserved.
	4	*
	5	* Redistribution and use in source and binary forms, with or without
	6	* modification, are permitted provided that the following conditions are
	7	* met:
	8	* * Redistributions of source code must retain the above copyright
	9	* notice, this list of conditions and the following disclaimer.
	10	* * Redistributions in binary form must reproduce the above copyright
	11	* notice, this list of conditions and the following disclaimer in the
	12	* documentation and/or other materials provided with the distribution.
	13	*
	14	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	15	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	16	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	17	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	18	* HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	19	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	20	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	21	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	22	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	23	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	24	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	25	*/
	26	#ifndef _CRYPTO_ECC_H
	27	#define _CRYPTO_ECC_H
	28
	29	#define ECC_MAX_DIGITS 4 /* 256 */
	30
	31	#define ECC_DIGITS_TO_BYTES_SHIFT 3
	32
	33	/**
	34	* ecc_is_key_valid() - Validate a given ECDH private key
	35	*
	36	* @curve_id: id representing the curve to use
c0ca1215	37	* @ndigits: curve's number of digits
3c4b2390	38	* @private_key: private key to be used for the given curve
c0ca1215	39	* @private_key_len: private key length
3c4b2390 SB	40	*
	41	* Returns 0 if the key is acceptable, a negative value otherwise
	42	*/
	43	int ecc_is_key_valid(unsigned int curve_id, unsigned int ndigits,
ad269597	44	const u64 *private_key, unsigned int private_key_len);
3c4b2390	45
6755fd26 TA	46	/**
	47	* ecc_gen_privkey() - Generates an ECC private key.
	48	* The private key is a random integer in the range 0 < random < n, where n is a
	49	* prime that is the order of the cyclic subgroup generated by the distinguished
	50	* point G.
	51	* @curve_id: id representing the curve to use
	52	* @ndigits: curve number of digits
	53	* @private_key: buffer for storing the generated private key
	54	*
	55	* Returns 0 if the private key was generated successfully, a negative value
	56	* if an error occurred.
	57	*/
	58	int ecc_gen_privkey(unsigned int curve_id, unsigned int ndigits, u64 *privkey);
	59
3c4b2390	60	/**
7380c56d	61	* ecc_make_pub_key() - Compute an ECC public key
3c4b2390 SB	62	*
3c4b2390 SB	63	* @curve_id: id representing the curve to use
c0ca1215	64	* @ndigits: curve's number of digits
3c4b2390	65	* @private_key: pregenerated private key for the given curve
c0ca1215	66	* @public_key: buffer for storing the generated public key
3c4b2390 SB	67	*
	68	* Returns 0 if the public key was generated successfully, a negative value
	69	* if an error occurred.
	70	*/
7380c56d TA	71	int ecc_make_pub_key(const unsigned int curve_id, unsigned int ndigits,
7380c56d TA	72	const u64 private_key, u64 public_key);
3c4b2390 SB	73
3c4b2390 SB	74	/**
8f44df15	75	* crypto_ecdh_shared_secret() - Compute a shared secret
3c4b2390 SB	76	*
3c4b2390 SB	77	* @curve_id: id representing the curve to use
c0ca1215	78	* @ndigits: curve's number of digits
3c4b2390	79	* @private_key: private key of part A
3c4b2390	80	* @public_key: public key of counterpart B
3c4b2390	81	* @secret: buffer for storing the calculated shared secret
3c4b2390	82	*
8f44df15	83	* Note: It is recommended that you hash the result of crypto_ecdh_shared_secret
3c4b2390 SB	84	* before using it for symmetric encryption or HMAC.
	85	*
	86	* Returns 0 if the shared secret was generated successfully, a negative value
	87	* if an error occurred.
	88	*/
8f44df15	89	int crypto_ecdh_shared_secret(unsigned int curve_id, unsigned int ndigits,
ad269597 TA	90	const u64 private_key, const u64 public_key,
ad269597 TA	91	u64 *secret);
3c4b2390	92	#endif