/// <summary>
/// Sends an SCTP packet to the remote peer.
/// </summary>
/// <param name="pkt">The packet to send.</param>
private void SendPacket(SctpPacket pkt)
{
if (!_wasAborted)
{
byte[] buffer = pkt.GetBytes();
_sctpTransport.Send(ID, buffer, 0, buffer.Length);
}
}
/// <summary>
/// Sends a SCTP chunk to the remote party.
/// </summary>
/// <param name="chunk">The chunk to send.</param>
internal void SendChunk(SctpChunk chunk)
{
if (!_wasAborted)
{
SctpPacket pkt = new SctpPacket(
_sctpSourcePort,
_sctpDestinationPort,
_remoteVerificationTag);
pkt.AddChunk(chunk);
byte[] buffer = pkt.GetBytes();
_sctpTransport.Send(ID, buffer, 0, buffer.Length);
}
}
/// <summary>
/// Send an SCTP packet with one of the error type chunks (ABORT or ERROR) to the remote peer.
/// </summary>
/// <param name=isAbort">Set to true to use an ABORT chunk otherwise an ERROR chunk will be used.</param>
/// <param name="desintationPort">The SCTP destination port.</param>
/// <param name="sourcePort">The SCTP source port.</param>
/// <param name="initiateTag">If available the initial tag for the remote peer.</param>
/// <param name="error">The error to send.</param>
private void SendError(
bool isAbort,
ushort destinationPort,
ushort sourcePort,
uint initiateTag,
ISctpErrorCause error)
{
SctpPacket errorPacket = new SctpPacket(
destinationPort,
sourcePort,
initiateTag);
SctpErrorChunk errorChunk = isAbort ? new SctpAbortChunk(true) : new SctpErrorChunk();
errorChunk.AddErrorCause(error);
errorPacket.AddChunk(errorChunk);
var buffer = errorPacket.GetBytes();
Send(null, buffer, 0, buffer.Length);
}
/// <summary>
/// Attempts to create an association with a remote party by sending an initialisation
/// control chunk.
/// </summary>
private void SendInit()
{
if (!_wasAborted)
{
// A packet containing an INIT chunk MUST have a zero Verification Tag (RFC4960 Pg 15).
SctpPacket init = new SctpPacket(_sctpSourcePort, _sctpDestinationPort, 0);
SctpInitChunk initChunk = new SctpInitChunk(
SctpChunkType.INIT,
VerificationTag,
TSN,
ARwnd,
_numberOutboundStreams,
_numberInboundStreams);
init.AddChunk(initChunk);
SetState(SctpAssociationState.CookieWait);
byte[] buffer = init.GetBytes();
_sctpTransport.Send(ID, buffer, 0, buffer.Length);
_t1Init = new Timer(T1InitTimerExpired, init, T1_INIT_TIMER_MILLISECONDS, T1_INIT_TIMER_MILLISECONDS);
}
}
