/// <summary>
/// Processes a STUN message received from a remote party.
/// </summary>
/// <param name="stunMessage">The received STUN message.</param>
/// <param name="remoteEndPoint">The remote end point the message was received from.</param>
private void ProcessStunMessage(STUNv2Message stunMessage, IPEndPoint remoteEndPoint)
{
//logger.LogDebug("STUN message received from remote " + remoteEndPoint + " " + stunMessage.Header.MessageType + ".");
if (stunMessage.Header.MessageType == STUNv2MessageTypesEnum.BindingRequest)
{
STUNv2Message stunResponse = new STUNv2Message(STUNv2MessageTypesEnum.BindingSuccessResponse);
stunResponse.Header.TransactionId = stunMessage.Header.TransactionId;
stunResponse.AddXORMappedAddressAttribute(remoteEndPoint.Address, remoteEndPoint.Port);
// ToDo: Check authentication.
string localIcePassword = LocalIcePassword;
byte[] stunRespBytes = stunResponse.ToByteBufferStringKey(localIcePassword, true);
//iceCandidate.LocalRtpSocket.SendTo(stunRespBytes, remoteEndPoint);
_rtpChannel.SendAsync(RTPChannelSocketsEnum.RTP, remoteEndPoint, stunRespBytes);
//iceCandidate.LastStunRequestReceivedAt = DateTime.Now;
//iceCandidate.IsStunRemoteExchangeComplete = true;
if (RemoteEndPoint == null)
{
RemoteEndPoint = remoteEndPoint;
RtpSession.SetDestination(RemoteEndPoint, RemoteEndPoint);
//OnIceConnected?.Invoke(iceCandidate, remoteEndPoint);
IceConnectionState = IceConnectionStatesEnum.Connected;
}
if (_remoteIceCandidates != null && !_remoteIceCandidates.Any(x =>
(x.NetworkAddress == remoteEndPoint.Address.ToString() || x.RemoteAddress == remoteEndPoint.Address.ToString()) &&
(x.Port == remoteEndPoint.Port || x.RemotePort == remoteEndPoint.Port)))
{
// This STUN request has come from a socket not in the remote ICE candidates list. Add it so we can send our STUN binding request to it.
IceCandidate remoteIceCandidate = new IceCandidate("udp", remoteEndPoint.Address, remoteEndPoint.Port, IceCandidateTypesEnum.host);
logger.LogDebug("Adding missing remote ICE candidate for " + remoteEndPoint + ".");
_remoteIceCandidates.Add(remoteIceCandidate);
// Some browsers require a STUN binding request from our end before the DTLS handshake will be initiated.
// The STUN connectivity checks are already scheduled but we can speed things up by sending a binding
// request immediately.
SendStunConnectivityChecks(null);
}
}
else if (stunMessage.Header.MessageType == STUNv2MessageTypesEnum.BindingSuccessResponse)
{
// TODO: What needs to be done here?
//if (_turnServerEndPoint != null && remoteEndPoint.ToString() == _turnServerEndPoint.ToString())
//{
// if (iceCandidate.IsGatheringComplete == false)
// {
// var reflexAddressAttribute = stunMessage.Attributes.FirstOrDefault(y => y.AttributeType == STUNv2AttributeTypesEnum.XORMappedAddress) as STUNv2XORAddressAttribute;
// if (reflexAddressAttribute != null)
// {
// iceCandidate.StunRflxIPEndPoint = new IPEndPoint(reflexAddressAttribute.Address, reflexAddressAttribute.Port);
// iceCandidate.IsGatheringComplete = true;
// logger.LogDebug("ICE gathering complete for local socket " + iceCandidate.RtpChannel.RTPLocalEndPoint + ", rflx address " + iceCandidate.StunRflxIPEndPoint + ".");
// }
// else
// {
// iceCandidate.IsGatheringComplete = true;
// logger.LogDebug("The STUN binding response received on " + iceCandidate.RtpChannel.RTPLocalEndPoint + " from " + remoteEndPoint + " did not have an XORMappedAddress attribute, rlfx address can not be determined.");
// }
// }
//}
//else
//{
// iceCandidate.LastStunResponseReceivedAt = DateTime.Now;
// if (iceCandidate.IsStunLocalExchangeComplete == false)
// {
// iceCandidate.IsStunLocalExchangeComplete = true;
// logger.LogDebug("WebRTC client STUN exchange complete for call " + CallID + ", candidate local socket " + iceCandidate.RtpChannel.RTPLocalEndPoint + ", remote socket " + remoteEndPoint + ".");
// SetIceConnectionState(IceConnectionStatesEnum.Connected);
// }
//}
}
else if (stunMessage.Header.MessageType == STUNv2MessageTypesEnum.BindingErrorResponse)
{
logger.LogWarning($"A STUN binding error response was received from {remoteEndPoint}.");
}
else
{
logger.LogWarning($"An unrecognised STUN request was received from {remoteEndPoint}.");
}
}
