Re: Resolved: locking oneself out, unroutable addresses

[Daniel Pittman <daniel@rimspace.net>]

gcrimp@vcn.bc.ca writes:
> On Sat, Jan 28, 2006 at 01:16:17PM +0100, Pascal Hambourg wrote:
>> Hello,
>> 
>> Daniel Pittman a écrit :
>> > gcrimpOvcn.bc.ca writes:
>> >> 
>> >>So, can anyone suggest what I should do with packets that have a
>> >>source address of 0.0.0.0?
>> > 
>> > Junk them -- they have no real business on your network, as 0.0.0.0
>> > isn't a valid assigned address on the live Internet.
>> 
>> Except at least when you use DHCP on your network. DHCP clients use 
>> 0.0.0.0 as a source address when issuing DHCP requests until they get a 
>> regular address from the server.
>
> Ah! Thanks.

Heh.  That wont help: you can't assign 0.0.0.0 to an interface in Linux,
so the DHCP client uses a "packet socket" -- reading direct from the
interface, bypassing the firewall.

Not that it isn't vaguely cleaner not to block it on that basis.

	Daniel