KeyExchangeSNtruP761X25519Sha512
using Org.BouncyCastle.Crypto;
using Org.BouncyCastle.Crypto.Parameters;
using Org.BouncyCastle.Pqc.Crypto.NtruPrime;
using Renci.SshNet.Abstractions;
using Renci.SshNet.Common;
using Renci.SshNet.Messages.Transport;
using System.Globalization;
namespace Renci.SshNet.Security
{
internal sealed class KeyExchangeSNtruP761X25519Sha512 : KeyExchangeECCurve25519
{
private SNtruPrimeKemExtractor _sntrup761Extractor;
public override string Name => "sntrup761x25519-sha512";
protected override int HashSize => 512;
protected override void StartImpl()
{
base.Session.RegisterMessage("SSH_MSG_KEX_ECDH_REPLY");
base.Session.KeyExchangeEcdhReplyMessageReceived += Session_KeyExchangeEcdhReplyMessageReceived;
SNtruPrimeKeyPairGenerator val = new SNtruPrimeKeyPairGenerator();
val.Init(new SNtruPrimeKeyGenerationParameters(CryptoAbstraction.SecureRandom, SNtruPrimeParameters.sntrup761));
AsymmetricCipherKeyPair val2 = val.GenerateKeyPair();
_sntrup761Extractor = new SNtruPrimeKemExtractor(val2.get_Private());
byte[] encoded = val2.get_Public().GetEncoded();
byte[] second = _impl.GenerateClientPublicKey();
_clientExchangeValue = encoded.Concat(second);
SendMessage(new KeyExchangeEcdhInitMessage(_clientExchangeValue));
}
protected override void FinishImpl()
{
base.Session.KeyExchangeEcdhReplyMessageReceived -= Session_KeyExchangeEcdhReplyMessageReceived;
}
protected override byte[] Hash(byte[] hashData)
{
return CryptoAbstraction.HashSHA512(hashData);
}
private void Session_KeyExchangeEcdhReplyMessageReceived(object sender, MessageEventArgs<KeyExchangeEcdhReplyMessage> e)
{
KeyExchangeEcdhReplyMessage message = e.Message;
base.Session.UnRegisterMessage("SSH_MSG_KEX_ECDH_REPLY");
HandleServerEcdhReply(message.KS, message.QS, message.Signature);
Finish();
}
private void HandleServerEcdhReply(byte[] hostKey, byte[] serverExchangeValue, byte[] signature)
{
_serverExchangeValue = serverExchangeValue;
_hostKey = hostKey;
_signature = signature;
if (serverExchangeValue.Length != _sntrup761Extractor.get_EncapsulationLength() + X25519PublicKeyParameters.KeySize)
throw new SshConnectionException(string.Format(CultureInfo.CurrentCulture, "Bad Q_S length: {0}.", serverExchangeValue.Length), DisconnectReason.KeyExchangeFailed);
byte[] array = serverExchangeValue.Take(_sntrup761Extractor.get_EncapsulationLength());
byte[] first = _sntrup761Extractor.ExtractSecret(array);
byte[] second = _impl.CalculateAgreement(serverExchangeValue.Take(_sntrup761Extractor.get_EncapsulationLength(), X25519PublicKeyParameters.KeySize));
base.SharedKey = CryptoAbstraction.HashSHA512(first.Concat(second));
}
}
}