#!/bin/sh
#
#	@(#) generate-uniq-local-ipv6-unicast-addr.sh
#
#	(c) Sep 2004	Holger Zuleger 
#
#	do what the name suggest in coordinance to
#	draft-ietf-ipv6-unique-local-unicast-addr-05.txt (June 2004)
#
#	firstpart = 64-Bit NTP time
#	secondpart = EUI-64 Identifier or 48 Bit MAC-Adress
#	md5 ($firstpart | $secondpart )
#	use least significant 40 Bits of md5sum
#	Build global Prefix (locally assigned == FD00::/8)
#	
NTPSERVER=pool.ntp.org

firstpart=`ntpdate -d -q $NTPSERVER |
	sed  -n "/reference/s/^reference time: *\([^ ]*\) .*/\1/p" |
	tr -d "."`

secondpart=`ifconfig eth0 |
	grep "inet6 addr: fe80" |
	sed  -n "s|^.*::\([^/]*\)/.*|\1|p" |
	tr -d ":"`

echo ${firstpart}${secondpart} | md5sum 

globalid=`echo ${firstpart}${secondpart} | md5sum | cut -c23-32`

echo fd${globalid} | sed "s|\(....\)\(....\)\(....\)|\1:\2:\3::/48|"