public void BindingRequestWithUsernameToBytesUnitTest()
{
Console.WriteLine(System.Reflection.MethodBase.GetCurrentMethod().Name);
STUNv2Message initMessage = new STUNv2Message(STUNv2MessageTypesEnum.BindingRequest);
initMessage.AddUsernameAttribute("someusernamex");
byte[] stunMessageBytes = initMessage.ToByteBuffer(null, false);
Console.WriteLine(BitConverter.ToString(stunMessageBytes));
Assert.IsTrue(stunMessageBytes.Length % 4 == 0);
}
private void SendStunConnectivityChecks()
{
try
{
while (!IsClosed)
{
try
{
// If one of the ICE candidates has the remote RTP socket set then the negotiation is complete and the STUN checks are to keep the connection alive.
if (LocalIceCandidates.Any(x => x.IsConnected == true))
{
var iceCandidate = LocalIceCandidates.First(x => x.IsConnected == true);
// Remote RTP endpoint gets set when the DTLS negotiation is finished.
if (iceCandidate.RemoteRtpEndPoint != null)
{
//logger.LogDebug("Sending STUN connectivity check to client " + iceCandidate.RemoteRtpEndPoint + ".");
string localUser = LocalIceUser;
STUNv2Message stunRequest = new STUNv2Message(STUNv2MessageTypesEnum.BindingRequest);
stunRequest.Header.TransactionId = Guid.NewGuid().ToByteArray().Take(12).ToArray();
stunRequest.AddUsernameAttribute(RemoteIceUser + ":" + localUser);
stunRequest.Attributes.Add(new STUNv2Attribute(STUNv2AttributeTypesEnum.Priority, new byte[] { 0x6e, 0x7f, 0x1e, 0xff }));
stunRequest.Attributes.Add(new STUNv2Attribute(STUNv2AttributeTypesEnum.UseCandidate, null)); // Must send this to get DTLS started.
byte[] stunReqBytes = stunRequest.ToByteBufferStringKey(RemoteIcePassword, true);
iceCandidate.LocalRtpSocket.SendTo(stunReqBytes, iceCandidate.RemoteRtpEndPoint);
iceCandidate.LastSTUNSendAt = DateTime.Now;
}
var secondsSinceLastResponse = DateTime.Now.Subtract(iceCandidate.LastCommunicationAt).TotalSeconds;
if (secondsSinceLastResponse > ICE_TIMEOUT_SECONDS)
{
logger.LogWarning("No STUN response was received on a connected ICE connection for " + secondsSinceLastResponse + "s, closing connection.");
iceCandidate.IsDisconnected = true;
if (LocalIceCandidates.Any(x => x.IsConnected == true) == false)
{
// If there are no connected local candidates left close the peer.
Close();
break;
}
}
}
else
{
if (_remoteIceCandidates.Count() > 0)
{
foreach (var localIceCandidate in LocalIceCandidates.Where(x => x.IsStunLocalExchangeComplete == false && x.StunConnectionRequestAttempts < MAXIMUM_STUN_CONNECTION_ATTEMPTS))
{
localIceCandidate.StunConnectionRequestAttempts++;
// ToDo: Include srflx and relay addresses.
// Only supporting UDP candidates at this stage.
foreach (var remoteIceCandidate in RemoteIceCandidates.Where(x => x.Transport.ToLower() == "udp" && x.NetworkAddress.NotNullOrBlank() && x.HasConnectionError == false))
{
try
{
IPAddress remoteAddress = IPAddress.Parse(remoteIceCandidate.NetworkAddress);
logger.LogDebug("Sending authenticated STUN binding request " + localIceCandidate.StunConnectionRequestAttempts + " from " + localIceCandidate.LocalRtpSocket.LocalEndPoint + " to WebRTC peer at " + remoteIceCandidate.NetworkAddress + ":" + remoteIceCandidate.Port + ".");
string localUser = LocalIceUser;
STUNv2Message stunRequest = new STUNv2Message(STUNv2MessageTypesEnum.BindingRequest);
stunRequest.Header.TransactionId = Guid.NewGuid().ToByteArray().Take(12).ToArray();
stunRequest.AddUsernameAttribute(RemoteIceUser + ":" + localUser);
stunRequest.Attributes.Add(new STUNv2Attribute(STUNv2AttributeTypesEnum.Priority, new byte[] { 0x6e, 0x7f, 0x1e, 0xff }));
stunRequest.Attributes.Add(new STUNv2Attribute(STUNv2AttributeTypesEnum.UseCandidate, null)); // Must send this to get DTLS started.
byte[] stunReqBytes = stunRequest.ToByteBufferStringKey(RemoteIcePassword, true);
localIceCandidate.LocalRtpSocket.SendTo(stunReqBytes, new IPEndPoint(IPAddress.Parse(remoteIceCandidate.NetworkAddress), remoteIceCandidate.Port));
localIceCandidate.LastSTUNSendAt = DateTime.Now;
}
catch (System.Net.Sockets.SocketException sockExcp)
{
logger.LogWarning($"SocketException sending STUN request to {remoteIceCandidate.NetworkAddress}:{remoteIceCandidate.Port}, removing candidate. {sockExcp.Message}");
remoteIceCandidate.HasConnectionError = true;
}
}
}
}
}
}
catch (Exception excp)
{
logger.LogError("Exception SendStunConnectivityCheck ConnectivityCheck. " + excp);
}
if (!IsClosed)
{
Thread.Sleep(ESTABLISHED_STUN_BINDING_PERIOD_MILLISECONDS);
}
}
}
catch (Exception excp)
{
logger.LogError("Exception SendStunConnectivityCheck. " + excp);
}
}