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Re: blocking DHCP requests



> Does your dhcpd server listen on wi0 ?
>
> /Sigfred
>
>
> On Saturday 02 October 2004 18.28, you wrote:
>> I'm trying to block wireless clients in using my DHCP-server. The
>> problem is that these clients are still able to retrieve IP-information
>> from the DHCP-server. If I understand the hereby included pf.conf,
>> everything (except UDP domain and TCP ssh) is blocked into entering
>> $wir_if (which comes from $wir_if:network). Doesn't this also mean that
>> an DHCP-request is blocked? Any suggestions in what I'm missing?
>>
>
Hello,
Indeed does the DHCP-server listen on wi0...If I understand correctly now
the DHCP daemon is written to use pcap instead of network sockets. This
means that the offers send out by the daemon can not be filtered(?) .
Quote from another user...
"I know that the dhcp* subsystem, was fundamentally written using pcap,
so that it did not use normal network sockets to request and accept
answers, at least I know that the dhcpclient worked this way for sure.
 I'm not sure that the dhcpd daemon worked this way, so this is
something that deserves some follow-up...  The dhcpclient in OpenBSD
changed this in 3.5, I know because I had to put pf rules in place for
the client to work on my DSL public interface.  The dhcpd server may
well use proper sockets at this time..."
A simple solution to this problem would be to remove wi0 from
dhcpd.interfaces, but I wonder; is it 'wise' to give daemons the option to
'bypass' pf?