public async Task <IConnection> CompletePreambleAsync(TimeSpan timeout)
{
var timeoutHelper = new TimeoutHelper(timeout);
var parent = this;
if (!transportSettings.MessageEncoderFactory.Encoder.IsContentTypeSupported(Decoder.ContentType))
{
SendFault(FramingEncodingString.ContentTypeInvalidFault, ref timeoutHelper);
throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(new ProtocolException(SR.Format(
SR.ContentTypeMismatch, Decoder.ContentType, parent.transportSettings.MessageEncoderFactory.Encoder.ContentType)));
}
IStreamUpgradeChannelBindingProvider channelBindingProvider = null;
StreamUpgradeAcceptor upgradeAcceptor = null;
if (transportSettings.Upgrade != null)
{
channelBindingProvider = transportSettings.Upgrade.GetProperty <IStreamUpgradeChannelBindingProvider>();
upgradeAcceptor = transportSettings.Upgrade.CreateUpgradeAcceptor();
}
var currentConnection = Connection;
UpgradeState upgradeState = UpgradeState.None;
while (true)
{
if (size == 0 && CanReadAndDecode(upgradeState))
{
size = await currentConnection.ReadAsync(0, connectionBuffer.Length, timeoutHelper.RemainingTime());
if (size == 0)
{
throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(Decoder.CreatePrematureEOFException());
}
}
while (true)
{
if (CanReadAndDecode(upgradeState))
{
int bytesRead = Decoder.Decode(connectionBuffer, offset, size);
if (bytesRead > 0)
{
offset += bytesRead;
size -= bytesRead;
}
}
switch (Decoder.CurrentState)
{
case ServerSingletonDecoder.State.UpgradeRequest:
switch (upgradeState)
{
case UpgradeState.None:
//change the state so that we don't read/decode until it is safe
ChangeUpgradeState(ref upgradeState, UpgradeState.VerifyingUpgradeRequest);
break;
case UpgradeState.VerifyingUpgradeRequest:
if (upgradeAcceptor == null)
{
SendFault(FramingEncodingString.UpgradeInvalidFault, ref timeoutHelper);
throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(
new ProtocolException(SR.Format(SR.UpgradeRequestToNonupgradableService, Decoder.Upgrade)));
}
if (!upgradeAcceptor.CanUpgrade(Decoder.Upgrade))
{
SendFault(FramingEncodingString.UpgradeInvalidFault, ref timeoutHelper);
throw DiagnosticUtility.ExceptionUtility.ThrowHelperError(new ProtocolException(SR.Format(SR.UpgradeProtocolNotSupported, Decoder.Upgrade)));
}
ChangeUpgradeState(ref upgradeState, UpgradeState.WritingUpgradeAck);
// accept upgrade
await currentConnection.WriteAsync(ServerSingletonEncoder.UpgradeResponseBytes, 0, ServerSingletonEncoder.UpgradeResponseBytes.Length,
true, timeoutHelper.RemainingTime());
ChangeUpgradeState(ref upgradeState, UpgradeState.UpgradeAckSent);
break;
case UpgradeState.UpgradeAckSent:
IConnection connectionToUpgrade = currentConnection;
if (size > 0)
{
connectionToUpgrade = new PreReadConnection(connectionToUpgrade, connectionBuffer, offset, size);
}
ChangeUpgradeState(ref upgradeState, UpgradeState.BeginUpgrade);
break;
case UpgradeState.BeginUpgrade:
try
{
currentConnection = await InitialServerConnectionReader.UpgradeConnectionAsync(currentConnection, upgradeAcceptor, transportSettings);
connectionBuffer = currentConnection.AsyncReadBuffer;
if (channelBindingProvider != null &&
channelBindingProvider.IsChannelBindingSupportEnabled &&
channelBindingToken == null) //first one wins in the case of multiple upgrades.
{
channelBindingToken = channelBindingProvider.GetChannelBinding(upgradeAcceptor, ChannelBindingKind.Endpoint);
}
ChangeUpgradeState(ref upgradeState, UpgradeState.EndUpgrade);
ChangeUpgradeState(ref upgradeState, UpgradeState.UpgradeComplete);
}
catch (Exception exception)
{
if (Fx.IsFatal(exception))
{
throw;
}
WriteAuditFailure(upgradeAcceptor as StreamSecurityUpgradeAcceptor, exception);
throw;
}
break;
case UpgradeState.UpgradeComplete:
//Client is doing more than one upgrade, reset the state
ChangeUpgradeState(ref upgradeState, UpgradeState.VerifyingUpgradeRequest);
break;
}
break;
case ServerSingletonDecoder.State.Start:
SetupSecurityIfNecessary(upgradeAcceptor);
if (upgradeState == UpgradeState.UpgradeComplete || //We have done at least one upgrade, but we are now done.
upgradeState == UpgradeState.None) //no upgrade, just send the preample end bytes
{
ChangeUpgradeState(ref upgradeState, UpgradeState.WritingPreambleEnd);
// we've finished the preamble. Ack and return.
await currentConnection.WriteAsync(ServerSessionEncoder.AckResponseBytes, 0, ServerSessionEncoder.AckResponseBytes.Length,
true, timeoutHelper.RemainingTime());
//terminal state
ChangeUpgradeState(ref upgradeState, UpgradeState.PreambleEndSent);
}
//we are done, this.currentConnection is the upgraded connection
return(currentConnection);
}
if (size == 0)
{
break;
}
}
}
}