OpenGGSN IPv6 PDP context support

Dear all, I've been busy all day (and night) implementing IPv6 PDP context support in OpenGGSN. The related code is currently in gerrit for review, you can also use the 'laforge/ipv6' branch of openggsn.git In terms of configuration, all you need to do is to specify IPv6 address + prefix as the 'net'. If you don't specify a 'dynip' config option, it will automatically use the network/prefix specified in 'net'. My minimalistic example config file for testing looks like this: debug fg listen 127.0.0.6 net 2001:780:44:2000:0:0:0:0/120 Which means it is listening for GTP on IPv4 (no IPv6 on the GTP side supported), and will create a tun device with the stated IPv6 address and a /120 netmask. Your GGSN is 2001:780:44:2000::1, and UEs will get addresses allocated from 2001:780:44:2000::2 onwards. It's important to configure your UE to actually request and IPv6 PDP context. If no v4/v6 is specified in the request, it will default to IPv4. If IPv4 is requested while having a v6 pool configured, OpenGGSN will reject the PDP Context Creation due to not being able to serve a v4 PDP context. I don't have immediate plans for supporting IPv6 on the outer (transport) layer for now. I also have no plans to support v4 and v6 from a single OpenGGSN at this time. It's quite easy to run two different OpenGGSN instances in parallel, on two different IPv4 addresses for the GTP side, and then use OsmoSGSN's PDP context routing to those different GGSNs. This way it is possible to have a v4 APN and a v6 APN without having to do any additional development right now. Architecturally, having multiple IP pools (and some for v4 and some for v6) is definitely possible, and should actually be easy. We just need to switch to a configuration mechanism that supports something like this, such as libosmovty. Once we have a VTY based configuration, it should be simple to operate multiple IP pools or multiple virtual APNs on one OpenGGSN. WARNING: The Linux Kernel GTP code does *not* support IPv6 user payload at this point. So if you want IPv6, you will need to use regular, old-fashioned userspace GTP-U in OpenGGSN for now. Controbutions are always welcome, of course! Regards, Harald -- - Harald Welte <laforge(a)gnumonks.org> http://laforge.gnumonks.org/ ============================================================================ "Privacy in residential applications is a desirable marketing option." (ETSI EN 300 175-7 Ch. A6)