[Dnsmasq-discuss] Ability to not bind :: for DNS when binding wildcard

[Simon Kelley]

On 06/07/2020 14:05, Matthias May wrote:

> Hi Dominik
> 
> Well the system in question has
> net.ipv6.conf.all.disable_ipv6 = 1
> thus the expected output would be that no IPv6 bindings exist at all.
> I kind of understand that when IPv6 is disabled, that one would not expect to see :::53 in netstat -nlp
> On the other hand i also see that if no IPv6 address exist on the system, there is not much that can be done with :::53.
> In the end probably more a cosmetic issue.
> I was thinking into the direction that create_wildcard_listeners checks by itself if the system has IPv6
> enabled/disabled, and also expose this as a manual know for an user to set.
> 


I'd rather have something that checked the value of
net.ipv6.conf.all.disable_ipv6 than yet another configuration option.

A patch which


1) Added a function in src/util.c to check the value of something under
/proc/sys

2) Added code to call that and avoid the bind in create_wildcard_listeners


both taking into account that this has to compile on platforms other
than linux (#ifdef HAVE_LINUX_NETWORK)


would be fine.


Cheers,

Simon.