Subject: Re: [PATCH] netfilter: add CHECKSUM target

From: "Michael S. Tsirkin" <[email-masked]>
Date: Sun, 11 Jul 2010 15:27:08 +0300

On Fri, Jul 09, 2010 at 11:56:26AM +0200, Jan Engelhardt wrote:
> 
> On Friday 2010-07-09 00:29, Michael S. Tsirkin wrote:
> >
> > include/linux/netfilter_ipv4/ipt_CHECKSUM.h |   18 +++++++
> > net/ipv4/netfilter/Kconfig                  |   16 ++++++
> > net/ipv4/netfilter/Makefile                 |    1 +
> > net/ipv4/netfilter/ipt_CHECKSUM.c           |   72 +++++++++++++++++++++++++++
> 
> New modules should use xt.

I tried moving the module to xt_CHECKSUM but now
	iptables -A POSTROUTING -t mangle -p udp --dport 68 -j CHECKSUM --checksum-fill
does not to load the module.
It seems that xt_request_find_target in x_tables uses the prefix 'ip' for a module.
What am I missing?

> >+static unsigned int
> >+checksum_tg(struct sk_buff *skb, const struct xt_action_param *par)
> >+{
> >+	if (skb->ip_summed == CHECKSUM_PARTIAL) {
> >+		skb_checksum_help(skb);
> >+	}
> 
> - {}