[asterisk-dev] NAT mapping while binding to IPv6

[Ryan Wagoner]

On Tue, Sep 6, 2011 at 8:03 AM, Kevin P. Fleming <kpfleming at digium.com> wrote:
> On 09/05/2011 03:41 PM, Klaus Darilion wrote:
>>
>> On 04.09.2011 17:07, Jeremy Visser wrote:
>>>
>>> Hi folks,
>>>
>>> I'm having an issue with NAT mapping and IPv6. Basically the scenario
>>> is that if tcp/udpbindaddr=[::], then the nat=yes option I specified
>>> in sip.conf is ignored. This is a problem because the fact that some
>>> of my SIP clients supporting IPv6 doesn't magically mean the IPv4-only
>>> ones aren't behind NATs any more.
>>>
>>> So I'm forced to support v4-only in order to not break NAT'ed clients.
>>>
>>> In ast_sip_ouraddrfor() in chan_sip.c, there is some "if
>>> (ast_sockaddr_is_ipv6(&theirs))" logic which seems to divert along a
>>> separate code path for when binding to an IPv6 socket that doesn't
>>> support NAT mapping.
>>>
>>> I'm not a qualified C coder so please forgive me if I am completely
>>> wrong here, but am I right in guessing that the NAT handling code is
>>> hardcoded to expect AF_INET structures, whereas the code path taken if
>>> ast_sockaddr_is_ipv6() is true uses AF_INET6, leading to the fact that
>>> the nat= option is being ignored?
>>>
>>> I'm not cluey enough to know how this works, but what would it take to
>>> get nat=yes support while binding to an IPv6 address?
>>
>> If v4 and v6 are really handled different, then it should be fixed. IMO
>> nat=yes means nat=yes, regardless if transport is v4 or v6.
>
> Agreed; this is a serious bug and needs to be addressed ASAP.
>
> --
> Kevin P. Fleming
> Digium, Inc. | Director of Software Technologies
> Jabber: kfleming at digium.com | SIP: kpfleming at digium.com | Skype: kpfleming
> 445 Jan Davis Drive NW - Huntsville, AL 35806 - USA
> Check us out at www.digium.com & www.asterisk.org

Glad to hear this is going to be addressed now. I had mentioned it
back in Dec 2010 and there didn't seem to be any interest.

http://lists.digium.com/pipermail/asterisk-users/2010-December/256975.html

Ryan