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Diffstat (limited to 'crypto/ecc.h')
-rw-r--r-- | crypto/ecc.h | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/crypto/ecc.h b/crypto/ecc.h new file mode 100644 index 0000000..b5db4b9 --- /dev/null +++ b/crypto/ecc.h @@ -0,0 +1,83 @@ +/* + * 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); + +/** + * 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 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 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 |