Subject: Re: dhcpd(8) _cannot_ be completely disabled on an interface
To: None <tech-net@netbsd.org, tech-security@netbsd.org>
From: der Mouse <mouse@Rodents.Montreal.QC.CA>
List: tech-net
Date: 01/07/2002 16:03:43
> not having dug too deeply into dhcpd or the protocol, however, i
> remain unconvinced that not knowing the actual source hardware is
> acceptable.

I take it you mean "source hardware _address_", ie, MAC address, here.

> doesn't dhcpd need to know that in order to send the reply?

Yes - or at least, _someone_ needs to know it, and only DHCP has it.
I saw a list message saying that it's already present in the DHCP
payload, though.  (No idea what the Right Thing to do is if that's
different from the Ethernet sender MAC address.)

> and won't it need to use a bpf in order to do so?

Not necessarily.  It is likely enough to install an ARP entry for the
MAC address given and the IP address assigned to that client (which can
be done with a routing socket), and then send the packet as a normal
UDP packet.

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