Re: [squid-users] TPROXY does not redirect to squid port

Hey Peter,

Tproxy is working and pretty nice for many users.
You are probably missing couple rules in iptables and might not
understand fully tproxy effects.
I still doesn't understand the issue.

What OS are you using?
If you can tell me more about the system I might be able to understand
the issue.
Are these are the only iptables rules you are using?
What routing rules are you using?

The document:
http://wiki.squid-cache.org/Features/Tproxy4
is not up-to-date and the current linux kernels are supporting tproxy
out of the box.

If you can share the basic setup I would be able to help you a bit more.

Thanks,
Eliezer

On 27/01/14 19:18, Peter Warasin wrote:
> hi guys
>
>
> I configured a transparent proxy environment using TPROXY following the
> howto on the squid wikihttp://wiki.squid-cache.org/Features/Tproxy4
> I setup a tproxy port in squid on port 18080 and created the following
> iptables rule:
>
> -A PREROUTING -p tcp --dport 80 -j TPROXY --on-port 18080 --tproxy-mark
> 0x1/0x1
>
> But squid does never see packets coming in.
>
> So I tried with the following tool:
> https://github.com/kristrev/tproxy-example
> The same, packets are not seen.
>
> By chance I tried to redirect to port 80 instead of 18080, in order that
> redirection does not happen at all, and then packets were seen by the
> tproxy-example tool.
>
> Seems that redirection is not working correctly or not at all.
>
>
> I proved with iptables logging rules that routing is correct, because
> packets are coming in the INPUT chain instead of FORWARD and are marked
> as they should be.
>
> Also I see the following debug output when compiled the tproxy iptables
> modules with -DDEBUG:
>
> xt_TPROXY: redirecting: proto 6 194.232.104.141:80 ->
> 192.168.11.15:18080, mark: 1
>
> which I would say means redirection actually*is* taking place, or
> perhaps debug messages are only correct while redirection is not (?).
>
> I tried with both, squid 3.2.1 and 3.3.8 and with kernels 2.6.32 and
> 3.2.54 and combinations. Always the same result.
>
>
> Does anyone have some hints where I could look at in order to solve this?
>
> Thank you in advance
>
> Peter
Received on Mon Jan 27 2014 - 20:23:16 MST