1 files changed, 97 insertions, 0 deletions
diff --git a/net-scripts/net.modules.d/ip6to4.sh b/net-scripts/net.modules.d/ip6to4.sh
new file mode 100644
index 0000000..4dde13f
--- /dev/null
+++ b/net-scripts/net.modules.d/ip6to4.sh
@@ -0,0 +1,97 @@
+#!/bin/bash
+# Copyright (c) 2004-2006 Gentoo Foundation
+# Distributed under the terms of the GNU General Public License v2
+
+# Contributed by Roy Marples (uberlord@gentoo.org)
+
+# void ip6to4_depend(void)
+#
+# Sets up the dependancies for the module
+ip6to4_depend() {
+	after interface
+	functions interface_exists interface_get_address interface_tunnel
+}
+
+# void ip6to4_expose(void)
+#
+# Expose variables that can be configured
+ip6to4_expose() {
+	variables link
+}
+
+# bool ip6to4_start(char *interface)
+#
+# Configures IPv6 addresses to be added to the tunnel based on a IPv4
+# addresses on a pre-configured interface.
+# Returns 0 on success, otherwise 1.
+ip6to4_start() {
+	local iface="$1" addr=""
+	local ifvar="$(bash_variable "${iface}")"
+
+	# Ensure the interface is sit0 if we're using ifconfig
+	if [[ " ${MODULES[@]} " == *" ifconfig "* && ${iface} != "sit0" ]] ; then
+		eerror "ip6to4 can only on interface sit0 using ifconfig"
+		eerror "emerge sys-apps/iproute2 to use other interfaces"
+		return 1
+	fi
+
+	local host="link_${ifvar}"
+	if [[ -z ${!host} ]] ; then
+		eerror "link_${ifvar} is not set"
+		return 1
+	fi
+	
+	interface_exists "${!host}" true || return 1
+	
+	# An interface can have more than 1 ip address
+	local -a addrs=( $(interface_get_address "${!host}") )
+	if [[ -z ${addrs} ]] ; then
+		eerror "${!host} is not configured with an IPv4 address"
+		return 1
+	fi
+
+	local -a new=()
+	local addr=""
+	for addr in "${addrs[@]}" ; do
+		# Strip the subnet
+		local ip="${addr%/*}" subnet="${addr#*/}"
+		# We don't work on private IPv4 addresses
+		[[ ${ip} == "127."* ]] && continue
+		[[ ${ip} == "10."* ]] && continue
+		[[ ${ip} == "192.168."* ]] && continue
+		local i
+		for ((i=16; i<32; i++)); do
+			[[ ${ip} == "172.${i}."* ]] && break 
+		done
+		[[ ${i} -lt 32 ]] && continue
+	
+		veinfo "IPv4 address on ${!host}: ${ip}"
+		local ip6="$(printf "2002:%02x%02x:%02x%02x::1" ${ip//./ })"
+		veinfo "Derived IPv6 address: ${ip6}"
+
+		# Now apply our IPv6 address to our config
+		new=( "${new[@]}" "${ip6}/16" )
+	done	
+
+	if [[ -z ${new} ]] ; then
+		eerror "No global IPv4 addresses found on interface ${!host}"
+		return 1
+	fi
+
+	if [[ ${iface} != "sit0" ]] ; then
+		ebegin "Creating 6to4 tunnel on ${iface}"
+		interface_tunnel add "${iface}" mode sit ttl 255 remote any local "${ip}"
+		eend $? || return 1
+	fi
+	
+	# Now apply our config
+	config=( "${config[@]}" "${new[@]}" )
+
+	# Add a route for us, ensuring we don't delete anything else
+	local routes="routes_${ifvar}[@]"
+	eval "routes_${ifvar}=( \"\${!routes}\" \
+			\"2003::/3 via ::192.88.99.1 metric 2147483647\" )"
+}
+	
+# vim:ts=4
+# vim: set ft=sh ts=4 :