GELATOD(8)

NAME
gelatod - a CLAT configuration daemon

SYNOPSIS
gelatod [-dv]

DESCRIPTION
gelatod is a CLAT (Customer-side transLATor) configuration daemon. It is part of 464XLAT, an architecture for providing limited IPv4 connectivity across an IPv6-only network. It detects the presence of a NAT64 translator in IPv6 only networks and configures pf(4) to translate IPv4 packets into IPv6 packets for programs that do not work with DNS64.

Because address family translation overrides the routing table, it's only possible to use af-to in pf(4) on inbound rules. To make this work with localy generated traffic gelatod requires two pair(4) interfaces in different routing domains and an IPv4 default route pointing to the second pair(4) interface.

    ifconfig pair1 inet 192.0.0.4/29
    ifconfig pair2 rdomain 1
    ifconfig pair2 inet 192.0.0.1/29
    ifconfig pair1 patch pair2
    route add -host -inet default 192.0.0.1 -priority 48

Furthermore it needs an anchor in pf(4) called clat into which it will add address family translation rules.

For example, it will load rules like the following when it detects NAT64:

    pass in log quick on pair2 inet af-to inet6 \
        from 2001:db8::da68:f613:4573:4ed0 to 64:ff9b::/96 \
        rtable 0

The options are as follows:

-d  Do not daemonize. If this option is specified, gelatod will run in the foreground and log to stderr.

-v  Produce more verbose output. Multiple -v options increase the verbosity.

SEE ALSO
pair(4), pf(4), hostname.if(5), ifconfig(8), slaacd(8)

STANDARDS
M. Mawatari, M. Kawashima, C. Byrne, April 2013, RFC 6877, 464XLAT: Combination of Stateful and Stateless Translation.

T. Savolainen, J. Korhonen, D. Wing, November 2013, RFC 7050, Discovery of the IPv6 Prefix Used for IPv6 Address Synthesis.

L. Colitti, J. Linkova, April 2020, RFC 8781, Discovering PREF64 in Router Advertisements.

AUTHORS
-nosplit The gelatod program was written by Florian Obser <florian@openbsd.org>.