Re: little bit off topic CLAT-Daemon for 464xlat for "Linux" (not android)

[Tore Anderson <tore fud no>]

* Tore Anderson
> * Thomas Schäfer
>
> > Does anybody know a howto (ip (iproute2), kernel) or daemon-software for CLAT 
> > as part of 464XLAT under linux (not android) ?
>
> I don't have a HOWTO

You got me interested enough to trying TAYGA for myself. It does work.
Here is the HOWTO:

1) Ensure IPv6 forwarding is on, allowed, and that we'd accept RAs even
when forwarding is on (not default in linux)

$ echo 2 | tee /proc/sys/net/ipv6/conf/*/accept_ra
$ echo 1 | tee /proc/sys/net/ipv6/conf/*/forwarding
$ ip6tables -I FORWARD 1 -j ACCEPT

2) Connect to an IPv6-only 3GPP network, ensure it's working

$ pppd call nwn6
$ ip -6 address list scope global
5: ppp0: <POINTOPOINT,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 qlen 3
    inet6 2a00:e18:8000:6cd:0:1:d613:6c01/64 scope global dynamic
       valid_lft forever preferred_lft forever
$ ip -6 route list
fe80::/10 dev ppp0  metric 1
fe80::/10 dev ppp0  proto kernel  metric 256
default dev ppp0  metric 1
default via fe80::1:d613:6c40 dev ppp0  proto ra  metric 1024  expires 65516sec
$ ping6 2a02:c0::1
PING 2a02:c0::1(2a02:c0::1) 56 data bytes
64 bytes from 2a02:c0::1: icmp_seq=1 ttl=57 time=282 ms

3) use the public dns64/nat64 instance hosted by trex.fi because my
ISP's is broken at the moment :-(

$ echo nameserver 2001:67c:2b0::4 > /etc/resolv.conf
$ host v4.fud.no
v4.fud.no has address 87.238.60.0
v4.fud.no has IPv6 address 2001:67c:2b0:db32:0:1:57ee:3c00
$ ping6 v4.fud.no
$ ping6 -n v4.fud.no
PING v4.fud.no(2001:67c:2b0:db32:0:1:57ee:3c00) 56 data bytes
64 bytes from 2001:67c:2b0:db32:0:1:57ee:3c00: icmp_seq=1 ttl=40 time=346 ms

4) configure TAYGA using trex.fi's NAT64 prefix and picking a random
IPv6 address inside my ISP-assigned /64 as the CLAT source address
(::cla7). 192.0.0.4 is the same as Android uses and is found in
draft-byrne-v6ops-clatip:

$ echo tun-device clat > tayga.conf
$ echo ipv4-addr 192.168.255.1 >> tayga.conf
$ echo prefix 2001:67c:2b0:db32:0:1::/96 >> tayga.conf
$ echo map 192.0.0.4 2a00:e18:8000:6cd::c1a7 >> tayga.conf

5) set up routing and start TAYGA

$ tayga --mktun
$ ip link set dev clat up
$ ip route add 2a00:e18:8000:6cd::c1a7 dev clat
$ ip address add 192.0.0.4 dev clat
$ ip -4 route add default dev clat
$ tayga

(NOTE: if you're using Ethernet for your IPv6 connectivity instead
of PPP you might need to set up a static route to the ::c1a7 address
on the upstream router or use ND-proxy or something like that,
otherwise the return traffic to the ::c1a7 address will never reach
the TAYGA process.)

6) enjoy working 464XLAT'ed connectivity to IPv4 literals:

$ ip -4 route get 8.8.8.8
8.8.8.8 dev clat  src 192.0.0.4
$ ping 8.8.8.8
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
64 bytes from 8.8.8.8: icmp_seq=1 ttl=34 time=348 ms
$ curl -s4 http://greed.fud.no | grep '^Remote'
Remote addr: 195.140.194.199
Remote host: pool199.nat64.trex.fi

Tore