[PATCH V2] ocserv: fix ipv6 tun control on OpenBSD

[jvi]

>On Wed, 2016-06-01 at 19:10 +0200, Andrew Karpow wrote:
>> This fixes ipv6 tunnel support on OpenBSD. OpenBSD network stack
>> doesn't
>> enable the multicast flag on tun devices like FreeBSD - but this is
>> obligatory for ipv6.
>>
>> Error message without this patch:
>> main: tun.c:260: tun0: Error setting IPv6: Invalid argument
>
>Applied, thank you.
>
>

The same problem persists on FreeBSD. I've just installed ocserv so
haven't yet a chance look in-depth what the issue is but it seems
ocserv cannot legally set IPv6 address and returns an error.

ocserv[41876]: main[test0]: 192.168.1.3:63633 new user session
ocserv[41876]: main[test0]: 192.168.1.3:63633 selected IP: 10.250.0.101
ocserv[41876]: main[test0]: 192.168.1.3:63633 selected IP: cccc::28
ocserv[41876]: main[test0]: 192.168.1.3:63633 assigned IPv4: 10.250.0.101
ocserv[41876]: main[test0]: 192.168.1.3:63633 assigned IPv6: cccc::28/128
ocserv[41876]: main: tun.c:258: tun1: Error setting IPv6: Invalid argument

and IPv6 is not set. MTU remains above 1380 so that's not a problem.

Thanks.

jvi