Am 30.10.18 um 11:07 schrieb Thomas Schäfer: > Am 29.10.18 um 23:09 schrieb Gert Doering: >> Hi, >> >> On Mon, Oct 29, 2018 at 09:06:13PM +0000, Kristian McColm wrote: >>> Will this feature break VPNs that use NAT64 to connect to IPv4-only >>> OpenVPN servers? >> >> No. >> >> This is an opt-in feature which you can enable by pushing "block-ipv6" >> from the server to the client, to avoid IPv6 traffic (to, say, youtube) >> bypassing your IPv4-only VPN. >> >> If your VPN is dual-stacked *inside* the tunnel, you wouldn't enable >> this. If your VPN is IPv4-only, but the client has external IPv6 >> connectivity, you might consider enabling this. >> >> gert > > > Sure? > > NAT64 means the client has (only) IPv6 connectivity. I am not sure > about, if a openvpn connections survive from an IPv6-only/NAT64 endpoint > to an IPv4-only server (transport protocol is changing during the > transport from 6 to 4 and vice versa). May be they do it via NAT64 or > via 464xlat. But if you block IPv6 ("external") at the client, you will > lose also you connectivity. (except 464xlat which generates a v4 socket) > > I cannot test it at the moment. I have two IPv6-only configured ovpn > servers and two NAT64-ISP (tm and lrz) but no time to build an > IPv4-only-openvpn-Server.
This patch only adds code to reject ipv6 packets that are *already* in the tunnel. It still depends on having redirect-gateway ipv6 or a default route to your tun device to actually do anything. If your packets to the VPN server ended up inside the tunnel something else is wrong already. I can add a followup patch to clarify this. Arne _______________________________________________ Openvpn-devel mailing list Openvpn-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/openvpn-devel