Re: Accessing packet marking functions

[Andrew Beverley <andy@andybev.com>]

> >I am considering patching Squid proxy so that it retains a packet's mark
> >value if it could not be fetched from the cache. Squid already has
> >similar functionality for the TOS field, but I would like to extend this
> >to netfilter's mark feature.
> >
> >Can somebody point me in the right direction for the correct way of
> >setting and accessing the mark value of a packet? The TOS feature in
> >Squid uses setsockopt(). Is there an equivalent for mark? Should I be
> >using libnetfilter_queue?
> 
> setsockopt(fd, SOL_SOCKET, SO_MARK, ...)

Thanks for the help so far. To retrieve the mark should I just be using:

getsockopt(fd, SOL_SOCKET, SO_MARK, ...) ?

I keep getting a mark of 0 despite setting a mark in PREROUTING. My code
is as follows:

int mark = 0;
int marklen = sizeof(mark);
getsockopt(newsocket, SOL_SOCKET, SO_MARK, &mark, &marklen);



Thanks,

Andy