Example #1
0
        /// <summary>
        /// Get a Public Key for my Private Key
        /// </summary>
        /// <param name="secretKey"></param>
        /// <returns></returns>
        /// <exception cref="ArgumentNullException"></exception>
        /// <exception cref="ArgumentException"></exception>
        public static byte[] GetPublicKey(byte[] secretKey)
        {
            if (secretKey == null)
            {
                throw new ArgumentNullException(nameof(secretKey));
            }
            if (secretKey.Length != PrivateKeySizeInBytes)
            {
                throw new ArgumentException($"{nameof(secretKey)} must be {PrivateKeySizeInBytes}");
            }

            var publicKey = new byte[PrivateKeySizeInBytes];

            Array.Copy(sourceArray: secretKey, destinationArray: publicKey, length: PrivateKeySizeInBytes);

            ClampOperation.Clamp(s: publicKey);

            var a = GroupElementsOperations.ScalarMultiplicationBase(a: publicKey); // To MontgomeryX

            var tempX = FieldElementOperations.Add(f: ref a.Z, g: ref a.Y);         //Get X
            var tempZ = FieldElementOperations.Sub(f: ref a.Z, g: ref a.Y);

            tempZ = FieldElementOperations.Invert(z: ref tempZ); //Get Z

            // Obtains the Public Key
            var publicKeyFieldElement = FieldElementOperations.Multiplication(f: ref tempX, g: ref tempZ); //X*Z

            FieldElementOperations.ToBytes(s: publicKey, h: ref publicKeyFieldElement);
            return(publicKey);
        }
Example #2
0
        /// <summary>
        /// Creates a random private key
        /// </summary>
        /// <returns>32 random bytes that are clamped to a suitable private key</returns>
        public static byte[] GetRandomPrivateKey()
        {
            var privateKey = new byte[PrivateKeySizeInBytes];

            RandomNumberGenerator.Create().GetBytes(privateKey);
            ClampOperation.Clamp(s: privateKey, offset: 0);
            return(privateKey);
        }