private void OnClosingSigned(IPeer peer, ClosingSignedMessage message)
{
var channel = _channelService.Channels.SingleOrDefault(c => c.ChannelId == message.ChannelId.ToHex());
if (channel == null)
{
_logger.LogDebug($"Remote sent us a {nameof(ClosingSignedMessage)}, but there is no matching channel.");
peer.Messaging.Send(ErrorMessage.UnknownChannel(message.ChannelId));
return;
}
// TODO: verify signature
var signedCloseTx = BuildSignedCloseTransaction(channel, SignatureConverter.RawToTransactionSignature(message.Signature), message.FeeSatoshi);
if (channel.IsFunder)
{
bool isFairFee = IsFairFee(signedCloseTx, message.FeeSatoshi);
if (isFairFee)
{
_channelLoggingService.LogInfo(channel, "Mutual Close Transaction", signedCloseTx.ToString());
_blockchainClientService.SendTransaction(signedCloseTx);
}
else if (_failedFeeNegotiations.Contains(channel))
{
_logger.LogWarning("Unable to negotiate a fair fee for our closing transaction. Will do a unilateral close.");
UnilateralClose(channel);
}
else
{
_failedFeeNegotiations.Add(channel);
RespondWithClosingSigned(peer, channel);
}
}
else
{
RespondWithClosingSigned(peer, channel, message.FeeSatoshi);
}
_channelService.UpdateChannel(channel);
}
private void RespondWithClosingSigned(IPeer peer, LocalChannel channel, ulong fee = 0)
{
var oldState = channel.State;
ulong ourFeeRate = _blockchainClientService.GetFeeRatePerKw(3);
channel.State = LocalChannelState.ClosingSigned;
var builder = new CloseChannelTransactionBuilder(channel, _networkParameters);
builder.FeeSatoshi = 0;
var zeroFeeTx = builder.Build();
builder.FeeSatoshi = fee != 0 ? fee : TransactionFee.CalculateFee(ourFeeRate, (ulong)zeroFeeTx.GetSerializedSize(2, SerializationType.Network));
ClosingSignedMessage closingSignedMessage = new ClosingSignedMessage();
closingSignedMessage.FeeSatoshi = builder.FeeSatoshi;
closingSignedMessage.ChannelId = channel.ChannelId.HexToByteArray();
closingSignedMessage.Signature = builder.Sign().ToRawSignature();
peer.Messaging.Send(closingSignedMessage);
_channelLoggingService.LogStateUpdate(channel, oldState, "Respond with closing signed");
}
