private static void OnEavesdropperResponse(EavesdropperResponseEventArgs e)
{
EavesdropperResponseEventHandler handler = EavesdropperResponse;
if (handler != null)
{
handler(e);
}
}
private static void RequestIntercepted(IAsyncResult ar)
{
bool doTerminate = false;
bool shouldTerminate = false;
try
{
_processingRequests++;
using (Socket requestSocket = _listener.EndAcceptSocket(ar))
{
if (IsRunning)
{
_listener.BeginAcceptSocket(RequestIntercepted, null);
}
// Intercept the HTTP/HTTPS command from the local machine.
byte[] requestCommandBuffer = new byte[8192];
int length = requestSocket.Receive(requestCommandBuffer);
if (length == 0)
{
return;
}
byte[] requestCommand = new byte[length];
Buffer.BlockCopy(requestCommandBuffer, 0, requestCommand, 0, length);
// Create a WebRequest instance using the intercepted commands/headers.
byte[] payload = null;
HttpWebRequest request = GetRequest(requestCommand, ref payload);
// Attempt to retrieve more data if available from the current stream.
if (requestSocket.Available == request.ContentLength &&
payload == null)
{
payload = new byte[request.ContentLength];
requestSocket.Receive(payload);
}
// Notify the subscriber that a request has been constructed, and is ready to be sent.
if (EavesdropperRequest != null)
{
var e = new EavesdropperRequestEventArgs(request);
if (payload != null)
{
e.Payload = payload;
}
OnEavesdropperRequest(e);
if (e.Cancel)
{
return;
}
payload = e.Payload;
}
switch (request.Method)
{
case "CONNECT": return; // Let's focus on HTTP for now.
case "POST": // Send the request data to the server.
{
using (Stream requestStream = request.GetRequestStream())
requestStream.Write(payload, 0, payload.Length);
break;
}
}
using (var response = (HttpWebResponse)request.GetResponse())
{
if (IsCacheDisabled)
{
response.Headers["Cache-Control"] = "no-cache, no-store";
}
byte[] responseData = new byte[0];
using (Stream responseStream = response.GetResponseStream())
{
int readDataLength = 0;
byte[] responseDataBuffer = null;
byte[] readData = new byte[response.ContentLength < 0 ? 8192 : response.ContentLength];
while ((readDataLength = responseStream.Read(readData, 0, readData.Length)) > 0)
{
responseDataBuffer = new byte[responseData.Length + readDataLength];
Buffer.BlockCopy(responseData, 0, responseDataBuffer, 0, responseData.Length);
Buffer.BlockCopy(readData, 0, responseDataBuffer, responseData.Length, readDataLength);
responseData = responseDataBuffer;
}
}
// Notify the subscriber that a response has been intercepted, and is ready to be viewed.
if (EavesdropperResponse != null)
{
var e = new EavesdropperResponseEventArgs(response);
e.Payload = responseData;
OnEavesdropperResponse(e);
if (doTerminate = e.ShouldTerminate)
{
IsRunning = false;
}
if (e.Cancel)
{
return;
}
responseData = e.Payload;
}
// Reply with the server's response back to the client.
byte[] commandResponse = GetCommandResponse(request, response, responseData.Length);
requestSocket.Send(commandResponse);
if (responseData != null && responseData.Length != 0)
{
requestSocket.Send(responseData);
}
shouldTerminate = doTerminate;
}
}
}
catch { }
finally
{
--_processingRequests;
if ((_processingRequests < 1 && !_listener.Active) || shouldTerminate)
{
if (_listener.Active)
{
_listener.Stop();
Port = 0;
}
NativeMethods.DisableProxy();
_processingRequests = 0;
}
}
}
private static void OnEavesdropperResponse(EavesdropperResponseEventArgs e)
{
EavesdropperResponse?.Invoke(null, e);
}
private static void HandleClientResponse(EavesdropperRequestEventArgs requestArgs, Stream clientStream)
{
WebResponse webResponse = null;
try { webResponse = requestArgs.Request.GetResponse(); }
catch (WebException e) { webResponse = e.Response; }
if (webResponse == null)
{
return;
}
using (WebResponse response = webResponse)
{
if (IsCacheDisabled)
{
response.Headers["Cache-Control"] = "no-cache, no-store";
}
byte[] responsePayload = null;
using (var responseStream = response.GetResponseStream())
using (var responseBufferStream = new MemoryStream())
{
responseStream.CopyTo(responseBufferStream);
responsePayload = responseBufferStream.ToArray();
}
var responseArgs = new EavesdropperResponseEventArgs(response);
responseArgs.Payload = responsePayload;
OnEavesdropperResponse(responseArgs);
if (!responseArgs.Cancel)
{
string responseCommand = response.Headers.ToString();
var hResponse = (response as HttpWebResponse);
if (hResponse != null && !responseArgs.IsResponseOK)
{
responseCommand = $"HTTP/{hResponse.ProtocolVersion} {(int)hResponse.StatusCode} " +
$"{hResponse.StatusDescription}\r\n{responseCommand}";
}
else
{
responseCommand = "HTTP/1.1 200 OK\r\n" + responseCommand;
}
string responseCookies = FormatResponseCookies(response);
if (!string.IsNullOrWhiteSpace(responseCookies))
{
string innerCookies = responseCommand.GetChild("Set-Cookie: ", '\r');
responseCommand = responseCommand
.Replace("Set-Cookie: " + innerCookies + "\r\n", responseCookies);
}
if (responseCommand.Contains("Content-Length"))
{
string contentLengthChild =
responseCommand.GetChild("Content-Length: ", '\r');
responseCommand = responseCommand.Replace(
contentLengthChild + "\r", (responseArgs.Payload?.Length ?? 0) + "\r");
}
byte[] responseCommandPayload = Encoding.ASCII.GetBytes(responseCommand);
clientStream.Write(responseCommandPayload,
0, responseCommandPayload.Length);
if (responseArgs.Payload != null)
{
clientStream.Write(responseArgs.Payload,
0, responseArgs.Payload.Length);
}
}
}
}
private static void OnEavesdropperResponse(EavesdropperResponseEventArgs e)
{
EavesdropperResponse?.Invoke(null, e);
}
private static void HandleClientResponse(EavesdropperRequestEventArgs requestArgs, Stream clientStream)
{
WebResponse webResponse = null;
try { webResponse = requestArgs.Request.GetResponse(); }
catch (WebException e) { webResponse = e.Response; }
if (webResponse == null) return;
using (WebResponse response = webResponse)
{
if (IsCacheDisabled)
response.Headers["Cache-Control"] = "no-cache, no-store";
byte[] responsePayload = null;
using (var responseStream = response.GetResponseStream())
using (var responseBufferStream = new MemoryStream())
{
responseStream.CopyTo(responseBufferStream);
responsePayload = responseBufferStream.ToArray();
}
var responseArgs = new EavesdropperResponseEventArgs(response);
responseArgs.Payload = responsePayload;
OnEavesdropperResponse(responseArgs);
if (!responseArgs.Cancel)
{
string responseCommand = response.Headers.ToString();
var hResponse = (response as HttpWebResponse);
if (hResponse != null && !responseArgs.IsResponseOK)
{
responseCommand = $"HTTP/{hResponse.ProtocolVersion} {(int)hResponse.StatusCode} " +
$"{hResponse.StatusDescription}\r\n{responseCommand}";
}
else responseCommand = "HTTP/1.1 200 OK\r\n" + responseCommand;
string responseCookies = FormatResponseCookies(response);
if (!string.IsNullOrWhiteSpace(responseCookies))
{
string innerCookies = responseCommand.GetChild("Set-Cookie: ", '\r');
responseCommand = responseCommand
.Replace("Set-Cookie: " + innerCookies + "\r\n", responseCookies);
}
if (responseCommand.Contains("Content-Length"))
{
string contentLengthChild =
responseCommand.GetChild("Content-Length: ", '\r');
responseCommand = responseCommand.Replace(
contentLengthChild + "\r", (responseArgs.Payload?.Length ?? 0) + "\r");
}
byte[] responseCommandPayload = Encoding.ASCII.GetBytes(responseCommand);
clientStream.Write(responseCommandPayload,
0, responseCommandPayload.Length);
if (responseArgs.Payload != null)
{
clientStream.Write(responseArgs.Payload,
0, responseArgs.Payload.Length);
}
}
}
}
