Re: [gentoo-user] Blocking certain sites the easy way ?

[Mick]

On Thursday 28 May 2015 07:44:23 Meino.Cramer@×××.de wrote:
> Mick <michaelkintzios@×××××.com> [15-05-28 07:44]:
> > On Thursday 28 May 2015 06:11:08 Meino.Cramer@×××.de wrote:
> > > Hi,
> > >
> > > With wireshark I found, that firefox accesses sites on startup, from
> > > which I dont know, for what reason this access is needed or whether
> > > the NSA, CIA, FBI, BDN, MOSSAD (fill in what organisation you ever
> > > suspect to do such things) has invaded my PC.
> >
> > It may none of the above, but FF and any addons checking what the latest
> > version is of themselves, as well as the Google search on the default
> > hope page doing a DNS query or some such.
> >
> > > I want to block such accesses for two reasons: First is ...hmmm...
> > > to block that accesses...second is to find out what will not work
> > > than.
> > >
> > > I dont want to install and configure a complete full blown firewalled
> > > SEL-Linux thingy here and I dont want to reboot my Linux box for every
> > > new site I added. I am looking for a simple solution, which I can use
> > > without studying the history of TCP/IP and others... ;)))
> > >
> > > What can I use for this purpose?
> >
> > You could try an application layer filter[1], but I think it won't work
> > insofar the connections you observed are probably using ports and
> > protocols same as your day to day browsing activity.  Therefore you will
> > likely need to use iptables to block individual domains or IP addresses
> > and then regularly add to the list when the servers your browser wants
> > to contact change in that amorphous and reconfiguring cloud out there.
> >
> > You don't have to reboot your box when you change rules, but you'll need
> > to reload iptables.
> >
> >
> > [1] http://l7-filter.sourceforge.net/HOWTO-kernel
>
> Hi Mick,
>
> thanks for your help ! :)
>
> What mechanism is recommended to be used to reinstall/initiate the
> iptable rules while booting? Any Gentoo-ish? ;)

iptables save any rules in:  /var/lib/iptables/rules-save

You can edit this and then run '/sbin/iptables-apply -t 90' 

in case you have something wrong in there and there is a risk of locking 
yourself out.

Or run '/etc/init.d/iptables stop' then change /var/lib/iptables/rules-save to 
your liking and then '/etc/init.d/iptables start'


This is for vanilla iptables (IPv4).  There are other scripts available (like 
arnos-firewall) which have their own configuration files as a front end to 
iptables.

-- 
Regards,
Mick