Re: Raw Sockets and Netfiter

[David Poole <davep@portsmith.com>]

On Tue, 2003-03-25 at 00:06, Ethan Dameron wrote:
> If I have a an IP datagram in userspace and I send it via a raw socket
> created with socket(PF_INET, SOCK_RAW, IPPROTO_RAW) using the send()
> system call, will this packet traverse the netfilter chains?  If it
> does not traverse the firewall, how can I make it do so?
> Version: 6.0.463 / Virus Database: 262 - Release Date: 03/17/2003

What are you trying to do?  Not that I have a solution, but I'm running
into the same problem.  

The DHCP client uses PF_PACKET which bypasses the firewall. 
Consequently, I can't firewall off certain machines.  I've been fiddling
with -j QUEUE and running a user-space DHCP client but the reinjected
packets are going I know not where.

Also, with PF_PACKET, the DHCP client will receive all unicast and
broadcast packets.  On a busy network and a slow system (our embedded
Linux product), the client gets flooded.


-- 
David Poole <davep@portsmith.com>
Portsmith   http://www.portsmith.com
960 Broadway Avenue, Suite 300
Boise, ID  83706
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