/// <summary>
/// Called asynchronously when a request was successfully and we received the response
/// </summary>
/// <param name="args"></param>
/// <returns>true if client/server connection was terminated (and disposed) </returns>
private async Task <bool> HandleHttpSessionResponse(SessionEventArgs args)
{
try
{
//read response & headers from server
await args.WebSession.ReceiveResponse();
var response = args.WebSession.Response;
#if NET45
//check for windows authentication
if (EnableWinAuth &&
!RunTime.IsRunningOnMono &&
response.ResponseStatusCode == (int)HttpStatusCode.Unauthorized)
{
bool disposed = await Handle401UnAuthorized(args);
if (disposed)
{
return(true);
}
}
#endif
args.ReRequest = false;
//If user requested call back then do it
if (BeforeResponse != null && !response.ResponseLocked)
{
await BeforeResponse.InvokeParallelAsync(this, args, ExceptionFunc);
}
//if user requested to send request again
//likely after making modifications from User Response Handler
if (args.ReRequest)
{
//clear current response
await args.ClearResponse();
bool disposed = await HandleHttpSessionRequestInternal(args.WebSession.ServerConnection, args, false);
return(disposed);
}
response.ResponseLocked = true;
var clientStreamWriter = args.ProxyClient.ClientStreamWriter;
//Write back to client 100-conitinue response if that's what server returned
if (response.Is100Continue)
{
await clientStreamWriter.WriteResponseStatusAsync(response.HttpVersion, (int)HttpStatusCode.Continue, "Continue");
await clientStreamWriter.WriteLineAsync();
}
else if (response.ExpectationFailed)
{
await clientStreamWriter.WriteResponseStatusAsync(response.HttpVersion, (int)HttpStatusCode.ExpectationFailed, "Expectation Failed");
await clientStreamWriter.WriteLineAsync();
}
//Write back response status to client
await clientStreamWriter.WriteResponseStatusAsync(response.HttpVersion, response.ResponseStatusCode, response.ResponseStatusDescription);
response.ResponseHeaders.FixProxyHeaders();
if (response.ResponseBodyRead)
{
bool isChunked = response.IsChunked;
string contentEncoding = response.ContentEncoding;
if (contentEncoding != null)
{
response.ResponseBody = await GetCompressedResponseBody(contentEncoding, response.ResponseBody);
if (isChunked == false)
{
response.ContentLength = response.ResponseBody.Length;
}
else
{
response.ContentLength = -1;
}
}
await clientStreamWriter.WriteHeadersAsync(response.ResponseHeaders);
await clientStreamWriter.WriteResponseBodyAsync(response.ResponseBody, isChunked);
}
else
{
await clientStreamWriter.WriteHeadersAsync(response.ResponseHeaders);
//Write body if exists
if (response.HasBody)
{
await clientStreamWriter.WriteResponseBodyAsync(BufferSize, args.WebSession.ServerConnection.StreamReader,
response.IsChunked, response.ContentLength);
}
}
await clientStreamWriter.FlushAsync();
}
catch (Exception e)
{
ExceptionFunc(new ProxyHttpException("Error occured whilst handling session response", e, args));
Dispose(args.ProxyClient.ClientStream, args.ProxyClient.ClientStreamReader, args.ProxyClient.ClientStreamWriter,
args.WebSession.ServerConnection);
return(true);
}
return(false);
}
/// <summary>
/// This is the core request handler method for a particular connection from client
/// Will create new session (request/response) sequence until
/// client/server abruptly terminates connection or by normal HTTP termination
/// </summary>
/// <param name="client"></param>
/// <param name="httpCmd"></param>
/// <param name="clientStream"></param>
/// <param name="clientStreamReader"></param>
/// <param name="clientStreamWriter"></param>
/// <param name="httpsConnectHostname"></param>
/// <param name="endPoint"></param>
/// <param name="connectRequest"></param>
/// <param name="isTransparentEndPoint"></param>
/// <returns></returns>
private async Task <bool> HandleHttpSessionRequest(TcpClient client, string httpCmd, CustomBufferedStream clientStream,
CustomBinaryReader clientStreamReader, HttpResponseWriter clientStreamWriter, string httpsConnectHostname,
ProxyEndPoint endPoint, ConnectRequest connectRequest, bool isTransparentEndPoint = false)
{
bool disposed = false;
TcpConnection connection = null;
//Loop through each subsequest request on this particular client connection
//(assuming HTTP connection is kept alive by client)
while (true)
{
if (string.IsNullOrEmpty(httpCmd))
{
break;
}
var args = new SessionEventArgs(BufferSize, endPoint, HandleHttpSessionResponse)
{
ProxyClient = { TcpClient = client },
WebSession = { ConnectRequest = connectRequest }
};
try
{
string httpMethod;
string httpUrl;
Version version;
Request.ParseRequestLine(httpCmd, out httpMethod, out httpUrl, out version);
//Read the request headers in to unique and non-unique header collections
await HeaderParser.ReadHeaders(clientStreamReader, args.WebSession.Request.RequestHeaders);
var httpRemoteUri = new Uri(httpsConnectHostname == null
? isTransparentEndPoint ? string.Concat("http://", args.WebSession.Request.Host, httpUrl) : httpUrl
: string.Concat("https://", args.WebSession.Request.Host ?? httpsConnectHostname, httpUrl));
args.WebSession.Request.RequestUri = httpRemoteUri;
args.WebSession.Request.OriginalRequestUrl = httpUrl;
args.WebSession.Request.Method = httpMethod;
args.WebSession.Request.HttpVersion = version;
args.ProxyClient.ClientStream = clientStream;
args.ProxyClient.ClientStreamReader = clientStreamReader;
args.ProxyClient.ClientStreamWriter = clientStreamWriter;
//proxy authorization check
if (httpsConnectHostname == null && await CheckAuthorization(clientStreamWriter, args) == false)
{
args.Dispose();
break;
}
PrepareRequestHeaders(args.WebSession.Request.RequestHeaders);
args.WebSession.Request.Host = args.WebSession.Request.RequestUri.Authority;
#if NET45
//if win auth is enabled
//we need a cache of request body
//so that we can send it after authentication in WinAuthHandler.cs
if (EnableWinAuth && !RunTime.IsRunningOnMono && args.WebSession.Request.HasBody)
{
await args.GetRequestBody();
}
#endif
//If user requested interception do it
if (BeforeRequest != null)
{
await BeforeRequest.InvokeParallelAsync(this, args, ExceptionFunc);
}
if (args.WebSession.Request.CancelRequest)
{
args.Dispose();
break;
}
//create a new connection if hostname changes
if (connection != null && !connection.HostName.Equals(args.WebSession.Request.RequestUri.Host, StringComparison.OrdinalIgnoreCase))
{
connection.Dispose();
UpdateServerConnectionCount(false);
connection = null;
}
if (connection == null)
{
connection = await GetServerConnection(args, false);
}
//if upgrading to websocket then relay the requet without reading the contents
if (args.WebSession.Request.UpgradeToWebSocket)
{
//prepare the prefix content
var requestHeaders = args.WebSession.Request.RequestHeaders;
byte[] requestBytes;
using (var ms = new MemoryStream())
using (var writer = new HttpRequestWriter(ms))
{
writer.WriteLine(httpCmd);
writer.WriteHeaders(requestHeaders);
requestBytes = ms.ToArray();
}
await connection.Stream.WriteAsync(requestBytes, 0, requestBytes.Length);
string httpStatus = await connection.StreamReader.ReadLineAsync();
Version responseVersion;
int responseStatusCode;
string responseStatusDescription;
Response.ParseResponseLine(httpStatus, out responseVersion, out responseStatusCode, out responseStatusDescription);
args.WebSession.Response.HttpVersion = responseVersion;
args.WebSession.Response.ResponseStatusCode = responseStatusCode;
args.WebSession.Response.ResponseStatusDescription = responseStatusDescription;
await HeaderParser.ReadHeaders(connection.StreamReader, args.WebSession.Response.ResponseHeaders);
await clientStreamWriter.WriteResponseAsync(args.WebSession.Response);
//If user requested call back then do it
if (BeforeResponse != null && !args.WebSession.Response.ResponseLocked)
{
await BeforeResponse.InvokeParallelAsync(this, args, ExceptionFunc);
}
await TcpHelper.SendRaw(clientStream, connection.Stream,
(buffer, offset, count) => { args.OnDataSent(buffer, offset, count); }, (buffer, offset, count) => { args.OnDataReceived(buffer, offset, count); });
args.Dispose();
break;
}
//construct the web request that we are going to issue on behalf of the client.
disposed = await HandleHttpSessionRequestInternal(connection, args, false);
if (disposed)
{
//already disposed inside above method
args.Dispose();
break;
}
//if connection is closing exit
if (args.WebSession.Response.ResponseKeepAlive == false)
{
args.Dispose();
break;
}
args.Dispose();
// read the next request
httpCmd = await clientStreamReader.ReadLineAsync();
}
catch (Exception e)
{
ExceptionFunc(new ProxyHttpException("Error occured whilst handling session request", e, args));
break;
}
}
if (!disposed)
{
Dispose(clientStream, clientStreamReader, clientStreamWriter, connection);
}
return(true);
}
/// <summary>
/// Called asynchronously when a request was successfully and we received the response
/// </summary>
/// <param name="args"></param>
/// <returns>true if client/server connection was terminated (and disposed) </returns>
private async Task <bool> HandleHttpSessionResponse(SessionEventArgs args)
{
try
{
//read response & headers from server
await args.WebSession.ReceiveResponse();
if (!args.WebSession.Response.ResponseBodyRead)
{
args.WebSession.Response.ResponseStream = args.WebSession.ServerConnection.Stream;
}
//check for windows authentication
if (EnableWinAuth &&
!RunTime.IsRunningOnMono &&
args.WebSession.Response.ResponseStatusCode == "401")
{
var disposed = await Handle401UnAuthorized(args);
if (disposed)
{
return(true);
}
}
args.ReRequest = false;
//If user requested call back then do it
if (BeforeResponse != null && !args.WebSession.Response.ResponseLocked)
{
await BeforeResponse.InvokeParallelAsync(this, args);
}
//if user requested to send request again
//likely after making modifications from User Response Handler
if (args.ReRequest)
{
//clear current response
await args.ClearResponse();
var disposed = await HandleHttpSessionRequestInternal(args.WebSession.ServerConnection, args, false);
return(disposed);
}
args.WebSession.Response.ResponseLocked = true;
//Write back to client 100-conitinue response if that's what server returned
if (args.WebSession.Response.Is100Continue)
{
await WriteResponseStatus(args.WebSession.Response.HttpVersion, "100",
"Continue", args.ProxyClient.ClientStreamWriter);
await args.ProxyClient.ClientStreamWriter.WriteLineAsync();
}
else if (args.WebSession.Response.ExpectationFailed)
{
await WriteResponseStatus(args.WebSession.Response.HttpVersion, "417",
"Expectation Failed", args.ProxyClient.ClientStreamWriter);
await args.ProxyClient.ClientStreamWriter.WriteLineAsync();
}
//Write back response status to client
await WriteResponseStatus(args.WebSession.Response.HttpVersion, args.WebSession.Response.ResponseStatusCode,
args.WebSession.Response.ResponseStatusDescription, args.ProxyClient.ClientStreamWriter);
if (args.WebSession.Response.ResponseBodyRead)
{
var isChunked = args.WebSession.Response.IsChunked;
var contentEncoding = args.WebSession.Response.ContentEncoding;
if (contentEncoding != null)
{
args.WebSession.Response.ResponseBody = await GetCompressedResponseBody(contentEncoding, args.WebSession.Response.ResponseBody);
if (isChunked == false)
{
args.WebSession.Response.ContentLength = args.WebSession.Response.ResponseBody.Length;
}
else
{
args.WebSession.Response.ContentLength = -1;
}
}
await WriteResponseHeaders(args.ProxyClient.ClientStreamWriter, args.WebSession.Response);
await args.ProxyClient.ClientStream.WriteResponseBody(args.WebSession.Response.ResponseBody, isChunked);
}
else
{
await WriteResponseHeaders(args.ProxyClient.ClientStreamWriter, args.WebSession.Response);
//Write body only if response is chunked or content length >0
//Is none are true then check if connection:close header exist, if so write response until server or client terminates the connection
if (args.WebSession.Response.IsChunked || args.WebSession.Response.ContentLength > 0 ||
!args.WebSession.Response.ResponseKeepAlive)
{
await args.WebSession.ServerConnection.StreamReader
.WriteResponseBody(BufferSize, args.ProxyClient.ClientStream, args.WebSession.Response.IsChunked,
args.WebSession.Response.ContentLength);
}
//write response if connection:keep-alive header exist and when version is http/1.0
//Because in Http 1.0 server can return a response without content-length (expectation being client would read until end of stream)
else if (args.WebSession.Response.ResponseKeepAlive && args.WebSession.Response.HttpVersion.Minor == 0)
{
await args.WebSession.ServerConnection.StreamReader
.WriteResponseBody(BufferSize, args.ProxyClient.ClientStream, args.WebSession.Response.IsChunked,
args.WebSession.Response.ContentLength);
}
}
await args.ProxyClient.ClientStream.FlushAsync();
}
catch (Exception e)
{
ExceptionFunc(new ProxyHttpException("Error occured whilst handling session response", e, args));
Dispose(args.ProxyClient.ClientStream, args.ProxyClient.ClientStreamReader,
args.ProxyClient.ClientStreamWriter, args.WebSession.ServerConnection);
return(true);
}
return(false);
}
