///// <summary>
///// Calculate public key from private key seed
///// </summary>
///// <param name="privateKeySeed">Private key seed value</param>
///// <returns></returns>
//public static byte[] PublicKeyFromSeed(byte[] privateKeySeed) {
// Contract.Requires<ArgumentNullException>(privateKeySeed != null);
// Contract.Requires<ArgumentException>(privateKeySeed.Length == PrivateKeySeedSize);
// byte[] privateKey;
// byte[] publicKey;
// KeyPairFromSeed(out publicKey, out privateKey, privateKeySeed);
// CryptoBytes.Wipe(privateKey);
// return publicKey;
//}
///// <summary>
///// Calculate expanded form of private key from the key seed.
///// </summary>
///// <param name="privateKeySeed">Private key seed value</param>
///// <returns>Expanded form of the private key</returns>
//public static byte[] ExpandedPrivateKeyFromSeed(byte[] privateKeySeed) {
// Contract.Requires<ArgumentNullException>(privateKeySeed != null);
// Contract.Requires<ArgumentException>(privateKeySeed.Length == PrivateKeySeedSize);
// byte[] privateKey;
// byte[] publicKey;
// KeyPairFromSeed(out publicKey, out privateKey, privateKeySeed);
// CryptoBytes.Wipe(publicKey);
// return privateKey;
//}
///// <summary>
///// Calculate key pair from the key seed.
///// </summary>
///// <param name="publicKey">Public key</param>
///// <param name="expandedPrivateKey">Expanded form of the private key</param>
///// <param name="privateKeySeed">Private key seed value</param>
//public static void KeyPairFromSeed(out byte[] publicKey, out byte[] expandedPrivateKey, byte[] privateKeySeed) {
// Contract.Requires<ArgumentNullException>(privateKeySeed != null);
// Contract.Requires<ArgumentException>(privateKeySeed.Length == PrivateKeySeedSize);
// var pk = new byte[PublicKeySize];
// var sk = new byte[ExpandedPrivateKeySize];
// Ed25519Operations.crypto_sign_keypair(pk, 0, sk, 0, privateKeySeed, 0);
// publicKey = pk;
// expandedPrivateKey = sk;
//}
public static void PrehashedKeyPairFromSeed(out byte[] publicKey, out byte[] prehashedPrivateKey, byte[] privateKeySeed)
{
Contract.Requires <ArgumentNullException>(privateKeySeed != null);
Contract.Requires <ArgumentException>(privateKeySeed.Length == PrivateKeySeedSize);
var pk = new byte[PublicKeySize];
var sk = new byte[ExpandedPrivateKeySize];
var skh = new byte[ExpandedPrivateKeySize];
Ed25519Operations.crypto_sign_keypair(pk, 0, sk, 0, privateKeySeed, 0);
publicKey = pk;
Ed25519Operations.crypto_sign_private_prehash(sk, skh);
prehashedPrivateKey = skh;
}