SocksSvc v1.07

Welcome to SocksSvc, a collection of freeware MFC classes to implement a simple Socks server.

The idea behind SocksSvc was originally to learn about the Socks protocol and how it is implemented on Win32.

For detailed information about the Socks Protocol you should read RFC 1928 (Socks 5), RFC 1929 (Username / Password authentication for Socks 5) and the Socks 4 specification.

Please note that SocksSvc is only meant as a simple tutorial on writing server side TCP applications and it should not be treated as code which is an enterprise grade socks proxy. For that I would suggest the user look at something like Squid which is a HTTP proxy or Dante.

The classes which constitute SocksSvc are:

CSocksServerSettings: This class contains the settings which are used to configure the Socks server. Example member variables in this class include the port to listen on and the valid protocols to support. If you are developing a stand alone socks server based on SocksSvc, you could for example store all the variables for the CSocksServerSettings instance in an ini file or in the registry.

CSocksServer: This is the actual class which implements the Socks server. It has a number of very simple functions to allow you to control the state of the socks server such as Start and Stop. Internally a background thread is spun off to handle the client connections.

CSocksClient: This class is used in the CSocksServer class to handle client connections. It handles the parsing of client requests and returning the appropriate response. A number of virtual functions are provided to allow end user customisation.

Various other help classes and structures are provided including a number of classes I have already developed independent of SocksSvc.

Features

• Supports Socks 4 and / or Socks 5.
• Supports Socks 5 username / password authentication.
• Supports Socks 5 anonymous authentication.
• Supports Socks 5 DNS proxying
• Supports listening on a specific IP address.
• Supports making outbound connections on a specific IP address.
• Compact and easy to follow implementation.
• The code can be used in a console application without any problems.
• The classes are fully Unicode compliant and include Unicode built options in the workspace file.
• Uses a thread pool to improve server performance.

Copyright

• You are allowed to include the source code in any product (commercial, shareware, freeware or otherwise) when your product is released in binary form.
• You are allowed to modify the source code in any way you want except you cannot modify the copyright details at the top of each module.
• If you want to distribute source code with your application, then you are only allowed to distribute versions released by the author. This is to maintain a single distribution point for the source code.

Usage

• To use the class in your code add all the header and cpp files from the sample app except main.cpp and stdafx.h/cpp.
• Your code will need to include MFC either statically or dynamically.
• To see the class in action, have a look at the code in InitInstance in the module "main.cpp" on how to start up and stop the server.
• Please note that if you want to compile the code, then you will need to download a number of classes from my web site, independent of the files in the Socks download. They include CWaitableTimer, CDirectedThreadPoolQueue, CIOCPThreadPoolQueue, CThreadPoolServer and CWSocket source code separately from my web site at www.naughter.com and copy in the various files into your SocksSvc's source code directory. These downloads are from my W3MFC (www.naughter.com/w3mfc.html) and WaitableTimer (www.naughter.com/waitabletimer.html) pages.
• The code requires at a minimum VC 2013 and will not compile with earlier versions of Visual C++.

History

V1.07 (30 November 2017)

• Replaced CString::operator LPC*STR() calls with CString::GetString calls

V1.06 (10 February 2017)

• Updated copyright details.
• Replaced BOOL with bool throughout codebase
• Replaced NULL with nullptr throughout codebase
• Updated the code to compile cleanly in VC 2013 - 2015. The code now requires at a minimum VC 2013
• Updated the code to handle IPv6 Socks v5 support
• Added SAL annotations to all the code
• Fixed up logic in CSocksClient::DoSocks5Negotiation to pick an appropriate socks5 client method
• Reworked all CSocksSocket::Read methods to avoid the use of "new".
• Updated all the CSocksSocket::Read methods to handle WSAEWOULDBLOCK errors.
• Updated CSocksClient::Relay method to handle WSAEWOULDBLOCK errors.
• Updated CSocksClient::SendConnectionResponsev5 method to return bound server address and port number in IPv4 and IPv6 connection responses.

V1.05 (15 January 2007)

• Updated copyright details.
• Removed CSocksClient destructor as it was not really required.
• Optimized CSocksClient constructor code
• Code now uses newer C++ style casts instead of C style casts.
• General review of code base for correctness.
• Removed unused code from CSocksClient::AllowThisOutboundConnection and CSocksClient::OnEndRelay
• Updates to allow the code to clean compile on VC 2005
• Optimized CSocksServerSettings constructor code
• Optimized CSocksServer constructor code
• Optimized CSocksConnectionRequest constructor code
• Optimized CSocks5RequestDetails constructor code
• Fixed a number of memory leaks in the CSocksSocket::Read methods
• Updated code to compile with latest version of the author's CWSocket class

V1.04 (13 February 2006)

• Updated the documentation to use the same style as the web site.
• Updated the copyright details of each module.
• Fixed graceful disconnect issues in CSocksSocket::Read and CSocksClient::Relay.
• Replaced all calls to CopyMemory with memcpy.
• Replaced all calls to ZeroMemory with memset.

V1.03 (7 September 2005)

• Updated the code to compile cleanly using the latest version of CWSocket.
• Updated the copyright details.
• Addition of a "SOCKSSVC_EXT_CLASS" which allows the code to be easily incorporated into an MFC extension DLL.
• Removed the m_bListenBind variable from the CSocksServerSettings as m_bListenBindAddress on its own is sufficient to specify whether binding should occur.
• Removed the m_bConnectBind variable from the CSocksServerSettings as m_bConnectBindAddress on its own is sufficient to specify whether binding should occur.
• Fixed a potential buffer overflow issue in the parsing of SOCKS4 connections requests.
• Fixed a typo in the logging of an error if socks 4 clients are not allowed.

V1.02 (13 January 2004)

• Used newer form of #pragma pack to avoid problems with non standard packing sizes.

V1.01 (3 March 2003)

• Fixed a bug in CSocksSocket::Read(CSocks5RequestDetails&,...) which was causing the port details to be read incorrectly from clients.

V1.0 (19 February 2003)

• Initial public release.

Contacting the Author

PJ Naughter
Email: pjna@naughter.com
Web: http://www.naughter.com
30 November 2017