[HttpToSocksProxy] How to redirect everything to an upstream SOCKS5 proxy

[4n1qz5skwv]

I don't the think the title actually describe it all or correctly.

Looking For

Say, User set 127.0.0.1:12345 as proxy in Firefox. And if the code is running, all the traffic will actually flow through a sock5 proxy (socks5://123.456.789.010:25456).

Main Purpose

So my main purpose is to let user use the socks5 proxy but without actually exposing it. I don't know what this method call. So i can't properly Google it. Is this possible using this library?

Please help. Thank you.

[abhinavsingh]

I guess you are looking for is a HttpToSocksProxyPoolPlugin i.e. something which will provide following tunnel:

Firefox <--- http proxy -----> 127.0.0.1:12345 <---- socks5 ----> 123.456.789.010:25456

This is possible but haven't been tried.

Here are a few suggestions if you want to hack around:

1. Take inspiration from ProxyPoolPlugin. This is EXACTLY what you need, but instead of upstream HTTP proxies you want to use SOCKS5 proxies, hence the name HttpToSocksProxyPoolPlugin :). You can have one or multiple upstream SOCKS5 proxies, hence pool used in the name.
2. For HttpToSocksProxyPoolPlugin to work, you will need to translate HTTP proxy packets (client) to SOCKS5 packet (server) and vice-versa. This is something ProxyPoolPlugin already do, but it needs to handle only HTTP packets.
3. To carry out SOCKS packet parsing/building, you will need an external library.

So:

1. Copy ProxyPoolPlugin as HttpToSocksProxyPoolPlugin
2. Update code to send outgoing HTTP proxy packets as corresponding SOCKS5 packets to upstream
3. Update code to parse incoming upstream packets as SOCKS5 packets and send to clients as HTTP packets

Most of the task should be straightforward except for dealing with SOCKS5 specific authentication and other workflows. But once connection has been established, you can pretty much tunnel packets as is.

Let me know about your thoughts. Thank you.

[4n1qz5skwv]

Thank you for your detailed reply. Unfortunately, i know nothing about this library, and when i heard that it maybe possible. i dropped it. No way i could have solve it. Also by more research i found this "qwj/python-proxy#112". exactly what i wanted.

[4n1qz5skwv]

Answer: Not directly but may be. Found an alternative.

[abhinavsingh]

Thanks you for the update. I think your use case is certainly possible with proxy.py, but there is no baked in solution for such protocol transformation. This can be a good feature to work upon in the future.

I checked python-proxy and it already has baked in SOCKS protocol support. Hence, it's a no-brainer that they can support such use case out of box. IIUC, you wanted incoming HTTP traffic to proxy to upstream SOCKS proxy. This will require more effort than just queuing packets back and forth between the clients. More so because proxy.py has no baked in SOCKS protocol support.

FWIW, as a matter of chance, today I sent out :)

• [SOCKS4] Packet parser & builder #1047

But, if an existing solution already works for you, I'll recommend just go for it.