Merging rc.d/network_ipv6 into rc.d/netif

[Bruce M. Simpson]

Mike Makonnen wrote:
> I would
> especially like feedback from folks more familiar with IPv6. One
> gotcha I've noticed is that if you boot with ipv6_enable turned
> off, then try to start IPv6 on an interface later on, it doesn't
> work because none of the interfaces (except lo0) has a link-local
> address (see rc.d/auto_linklocal). How can we fix this? Also, I
> would appreciate feedback on how stopping IPv6 on an interface
> should be handled. In rc.d/network_ipv6 it was handled at all.
> Currently, it goes through and deletes all
> IPv6 addresses on the interface.
>   

I agree. We should be able to add/remove IPv6 link-local addresses 
somehow at runtime, after boot, without necessarily bringing up IPv6 on 
an interface during boot.

I am thinking at some point it may be for the best if some of the code 
to do with address families is restructured so that the administrator is 
able to explicitly attach or detach protocol domains e.g. AF_INET, 
AF_INET6 to network interfaces on the command line, based on my 
experience of making the changes necessary for refcounting of various 
network stack structures.

I'd like to get this fixed going forward, though, as ever, other work 
takes priority...

Regards,
BMS