New preview patch for ipfw to pfil_hooks conversion

[Angelo Turetta]

----- Original Message ----- 
From: "Andre Oppermann" <andre at freebsd.org>
Sent: Monday, June 21, 2004 11:36 PM


> This patch significantly cleans up ip_input.c and ip_output.c.
>
> The following is included in this patch:
>
>   o Remove all ipfw related cruft from ip_input() and ip_output()
>   o New ip_fw_pfil.c file which contains all ipfw/pfil_hooks logic

IIRC, I had once a problem with a mixed setup where I used IPFILTER NAT &
IPFW DUMMYNET. Basically, there was an asymmetry in the order the two
filters were called, because the code in ip_input.c called IPFILTER before
entering the IPFW code, and ip_output.c did the same, while it should have
called first IPFW then IPFILTER. (beware, it might have been the opposite
WRT what was first in which function, I don't remember exactly).

Does your new code take this ordering issue into account? I suppose it would
be nice to be able to control the order filters are processed: I may like
IPFW to be 'wrapping' IPFILTER (that is, called before it during input, and
after it during output), while others might prefer the opposite. And anyway,
am I right the filter list should be traversed in opposite directions during
input versus output (maybe it's already so).

Ciao,
Angelo.