private void ServerReadCallback(IAsyncResult ar)
{
var state = ar.AsyncState as CommStateObject;
var pipe = state.Worker as NamedPipeServerStream;
var bytesRead = 0;
try
{
bytesRead = pipe.EndRead(ar);
}
catch { }
if (bytesRead > 0)
{
var data = ServerDataJuggle(bytesRead, pipe, state);
if (Crypto.VerifyHMAC(data))
{
var inbound = Crypto.Decrypt <AgentMessage>(data);
if (inbound != null)
{
Inbound.Enqueue(inbound);
}
}
}
var outbound = new AgentMessage {
Metadata = Metadata
};
if (Outbound.Count > 0)
{
outbound = Outbound.Dequeue();
}
var dataToSend = Crypto.Encrypt(outbound);
pipe.BeginWrite(dataToSend, 0, dataToSend.Length, new AsyncCallback(ServerWriteCallback), pipe);
}
private void ProcessTeamServerResponse(byte[] result)
{
if (Crypto.VerifyHMAC(result))
{
var message = Crypto.Decrypt <AgentMessage>(result);
if (message != null)
{
Inbound.Enqueue(message);
}
}
}
private void ServerReadCallback(IAsyncResult ar)
{
var state = ar.AsyncState as CommStateObject;
var stream = state.Worker as NetworkStream;
var bytesRead = 0;
try
{
bytesRead = stream.EndRead(ar);
}
catch { }
if (bytesRead > 0)
{
var data = DataJuggle(bytesRead, stream, state);
if (Crypto.VerifyHMAC(data))
{
var inbound = Crypto.Decrypt <AgentMessage>(data);
if (inbound != null)
{
Inbound.Enqueue(inbound);
}
}
AgentMessage outbound = new AgentMessage {
Metadata = Metadata
};
if (Outbound.Count > 0)
{
outbound = Outbound.Dequeue();
}
var encrypted = Crypto.Encrypt(outbound);
stream.BeginWrite(encrypted, 0, encrypted.Length, new AsyncCallback(ServerWriteCallback), stream);
}
}
private List <AgentMessage> ExtractAgentMessage(string webRequest)
{
List <AgentMessage> message = null;
var regex = Regex.Match(webRequest, "Message=([^\\s]+)");
if (regex.Captures.Count > 0)
{
var encrypted = Convert.FromBase64String(regex.Groups[1].Value);
if (CryptoController.VerifyHMAC(encrypted))
{
message = CryptoController.Decrypt <List <AgentMessage> >(encrypted);
}
else
{
OnAgentEvent?.Invoke(this, new AgentEvent("", AgentEventType.CryptoError, "HMAC validation failed on AgentMessage"));
}
}
return(message);
}
private AgentMetadata ExtractAgentMetadata(string webRequest)
{
AgentMetadata metadata = null;
var regex = Regex.Match(webRequest, "Cookie: Metadata=([^\\s].*)");
if (regex.Captures.Count > 0)
{
var encrypted = Convert.FromBase64String(regex.Groups[1].Value);
if (CryptoController.VerifyHMAC(encrypted))
{
metadata = CryptoController.Decrypt <AgentMetadata>(encrypted);
}
else
{
OnAgentEvent?.Invoke(this, new AgentEvent("", AgentEventType.CryptoError, "HMAC validation failed on AgentMetadata"));
}
}
return(metadata);
}
