strongSwan

I believe there is framed_ipv6_address attribute too. rfc6911, section 3.1, or I misread something?
Tobias Brunner wrote:

Please add support for processing ipv6 related attributes from radius in addition to ipv4 ones.

While RFC 3162 defines RADIUS attributes for IPv6 (Framed-Interface-Id, Framed-IPv6-Prefix) these currently don't have a counterpart in strongSwan's IKE implementation. That's mainly because we currently don't support RFC 5739, which defines the corresponding INTERNAL_IP6_LINK and INTERNAL_IP6_PREFIX configuration attributes.

One attribute defined in RFC 3162 that could be handled quite easily is Framed-IPv6-Pool, which we could use to find an address pool by name from which to assign an IP to the client.

I believe there is framed_ipv6_address attribute too. rfc6911, section 3.1, or I misread something?

No, you are quite right. Didn't see that. The patch in the radius-ipv6 branch adds support for the Framed-IPv6-Address and DNS-Server-IPv6-Address attributes.

Actually a suggestion:
Strongswan sends Framed-IPv6-Prefix in accounting requests. Shouldn't it actually send Framed-IPv6-Address? I believe it would be more appropriate, but not sure.

Actually a suggestion:
Strongswan sends Framed-IPv6-Prefix in accounting requests. Shouldn't it actually send Framed-IPv6-Address? I believe it would be more appropriate, but not sure.

Yes, probably. The comment there indicates an attempt to map the single IPv6 addresses we assign to clients to the Framed-IPv6-Prefix attribute. I pushed another commit to the radius-ipv6 branch that implements your suggestion.