Re: [PATCH iptables] libxtables: fix wrong naddr when using localhost

[Pablo Neira Ayuso <pablo@netfilter.org>]

On Wed, Mar 08, 2017 at 12:28:13AM +0100, Alexander Alemayhu wrote:
> $ iptables-translate -A INPUT -p tcp -s localhost --dport 8000 -j ACCEPT
> 
> gives
> 
>  nft add rule ip filter INPUT ip saddr 127.0.0.1 tcp dport 8000 counter accept
>  add rule ip filter INPUT ip saddr 127.0.0.1 tcp dport 8000 counter accept
> 
> with this patch we get
> 
>  nft add rule ip filter INPUT ip saddr 127.0.0.1 tcp dport 8000 counter accept

This is actually a generic problem:

# iptables -I INPUT -p tcp -s localhost

results in:

# iptables-save 
# Generated by iptables-save v1.6.1 on Wed Mar  8 10:53:07 2017
*filter
:INPUT ACCEPT [13:1628]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [4:317]
-A INPUT -s 127.0.0.1/32 -p tcp
-A INPUT -s 127.0.0.1/32 -p tcp
COMMIT
# Completed on Wed Mar  8 10:53:07 2017

Original problem was introduce at:

commit 2d2b5e046aa56a518160716a9ddf9df53fc79c1f
Author: Arpan Kapoor <rpnkpr@gmail.com>
Date:   Thu Mar 17 18:27:19 2016 +0530

    libxtables: Replace gethostbyname() with getaddrinfo()

Did you also run iptables tests? See iptables-test.py, although I
guess our test infrastructure is not catching up this case.

Thanks!