Support upstream SOCKS proxy

[tyll]

Implement support for SOCKS upstream proxy with DNS resolution via SOCKS, so mitmproxy can be easily tunnelled through "ssh -D".

[mhils]

I don't have the time do work on this at the moment, but if someone is interested, wrapping proxy.ServerConnection should do the job.

[kourosh3000]

Thank you

[niaoniaozz]

Hello, I am wondering if this feature is implemented in the current version or not.

[mhils]

Not yet, sorry.

[JeremyRand]

Hi, so I'm looking at the code for upstream HTTP(S) proxy support and it looks like it's mutually exclusive with running mitmproxy as a SOCKS proxy. I'm potentially interested in looking at adding upstream SOCKS support, but I'd prefer not to have that limitation. Is there an implementation reason for that exclusivity? Is there a good way to implement upstream SOCKS support such that that isn't a problem?

[absane]

Just commenting hoping to bump interest some. I've been trying to use Tor as an upstream proxy and it seems that Tor only supports Socks.

[samos123]

Would also like to have this feature.

[n0rz]

++

[malwarefun]

You can hook the makesocket call in tcp.py.
Install and import pysocks, then connect to your socks proxy (eg. set_proxy(socks.SOCKS5, "localhost", 9050))

[TonyStark]

@zhangyoufu i tried but i think its not working
@malwarefun can yo give script example...

[malwarefun]

Hi @TonyStark ,
Its been a while since I looked at this.. I think I did something like,

import socks
...
def makesocket(self):
    s = socks.socksocket()
    s.set_proxy(socks.SOCKS5, "localhost", 9050)
    return s

[TonyStark]

@malwarefun
i tried your code but it seems not working.
i also tried this code

import socks
s = socks.socksocket() # Same API as socket.socket in the standard lib
s.set_proxy(socks.SOCKS5, "localhost", 37760)
# Can be treated identical to a regular socket object
s.connect(("127.0.0.1", 8080))
s.sendall("GET / HTTP/1.1 ...")
print s.recv(4096)

but not working too

[ghost]

Hi there.
I am new to mitmproxy and i was wondering if i modify upstream proxy to support SOCKS, is mitmproxy a good choice for applying load balancing on multiple tor clients? is it suitable for this purpose?
thanks in advance.

[eliyastein]

Hi, sorry to bump an old thread, but has anyone gotten this to work? I'm looking to use Socks5 proxy as upstream.

[baptx]

@eliyastein I did it with proxychains
Related: #830

[eliyastein]

Thanks @baptx - I was actually able to do it using gost:

https://github.com/ginuerzh/gost

[q2dg]

Another option is #2813 (comment)

[scruel]

What a long time unsolved issue, hope support socks5 connect when use upstream mode and us socks5 proxy as its forward proxy.

[scruel]

Thanks @baptx - I was actually able to do it using gost:

https://github.com/ginuerzh/gost

socks.go:950: [socks5] 127.0.0.1:12915 -> 127.0.0.1:1089 : EOF
2021/08/15 23:12:56 socks.go:950: [socks5] 127.0.0.1:12805 -> 127.0.0.1:1089 : read tcp 127.0.0.1:12806->127.0.0.1:62323: i/o timeout

[bardic]

@eliyastein would be be able to explain your gost setup? I keep getting port is already in use errors.

[eliyastein]

@eliyastein would be be able to explain your gost setup? I keep getting port is already in use errors.

@bardic - it has been a while... but I'm looking at the script I wrote to make this work and it looks like it's something like this:

gost -L=localhost:LOCAL_PORT -F=socks5://localhost:PROXY_PORT

Then when I invoke mitm I pass along --mode upstream:localhost:LOCAL_PORT

So basically gost is forwarding the local port that you specify to the socks proxy. I imagine in your case the argument you pass to gost -F will be remote and not local like it was in my case. Of course if everything is local, make sure it's all running on different ports.

[bratao]

@mhils Hey, I need to tackle this task for my work, and I want to contribute back upstream.

Can you offer me any advice before I start? I´m planning to use https://github.com/romis2012/python-socks
What would be the right place/class to implement this feature? Before digging it, looks like a candidate would be ProxyConnectionHandler.

[mhils]

@bratao: A good first step would be to simply rewrite the existing HTTP Upstream Proxy Implementation with a SOCKSv5 one. Our proxy core is sans-io, which means that python-socks may not be an ideal fit. We already have a SOCKSv5 server Implementation, it'd make more sense to reuse the primitives there.

[nathe97]

Some news for this socks5 in upstream feature?

[gastonmorixe]

+1

[karser]

it's indeed a missing feature

Update: I found a workaround by using tinyproxy with the following configuration:

Port 8080
upstream socks5 localhost:8000
Allow 0.0.0.0/0