[lug] sendto(2) problem with ipv4/ipv6 addresses...

Bear Giles bgiles at coyotesong.com
Mon Apr 2 13:08:10 MDT 2012


Dual network stack implementations can recognize IPv4 addresses within the
IPv6 address space.

It's unlikely but you could also try the older format ::aa.bb.cc.dd (drop
the :ffff:).

Bear


On Mon, Apr 2, 2012 at 11:55 AM, Zan Lynx <zlynx at acm.org> wrote:

> On Mon, 2012-04-02 at 12:38 -0600, Alan Robertson wrote:
> > As part of the Assimilation Monitoring project (assimmon.org), I've
> > been writing some UDP network code to send packets.  It seems to work
> > fine when sending to the ipv6 loopback address (::1), but not when
> > sending to ipv4 addresses.  I'm sending to ipv4 addresses by using the
> > ipv4 part of the ipv6 address space ("::ffff:aa.bb.cc.dd").  Tcpdump
> > is showing that nothing is being sent - so the kernel is blocking this
> > call before it goes out.
>
> I believe that using IPv4 addresses mapped in IPv6 requires a gateway
> device to convert the protocol from IPv6 to IPv4. This seems to be
> called NAT-PT.
>
> Here is one source I Googled that describes configuring it on Linux:
> http://tomicki.net/ipv6.router.php
>
> --
> Knowledge Is Power
> Power Corrupts
> Study Hard
> Be Evil
>
> _______________________________________________
> Web Page:  http://lug.boulder.co.us
> Mailing List: http://lists.lug.boulder.co.us/mailman/listinfo/lug
> Join us on IRC: irc.hackingsociety.org port=6667 channel=#hackingsociety
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.lug.boulder.co.us/pipermail/lug/attachments/20120402/8b066b80/attachment.html>


More information about the LUG mailing list