Restricting browsers to only listed websites

[Tim]

On Fri, 2013-05-10 at 18:06 +0200, Reindl Harald wrote:
> but if the OP does not want a appliance between the machine
> and the not by him controlled router there not much left

There are probably browser plugins that could do it (parental controls,
perhaps), or the configuring a proxy configuration script, as I
mentioned earlier on.

For example, of how to actually do that, this website 
http://www.proxypacfiles.com/proxypac/index.php?option=com_content&view=article&id=54&Itemid=83
details the following:

  -- begin paste --

Blocking sites is also handy. This can be done for a number of reasons –
Spyware/malware sites are very good examples Blocking these sites can be
done very easily – Simply return a proxy value somewhere on a loopback
address so that the requests never actually leave the local machine to
take up network bandwidth. The only caveat with this is to ensure that
your selection of port number isn’t actually listening on the PC which
could odd behavior.

if (dnsDomainIs(host, ".badspyware.com") ||
    dnsDomainIs(host, ".worsespyware2.com")) {
return "PROXY 127.0.0.1:48890";
}

  -- end paste --

I might add to that and actually run a simple webserver on the same
machine that responds to any and all local connection attempts to it.
It could respond with an error message saying why it failed, e.g. saying
that only the following list of sites are allowed on this machine (and
list your allowed sites on the page).

-- 
[tim at localhost ~]$ uname -r
2.6.27.25-78.2.56.fc9.i686

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