# 6in4.sh - IPv6-in-IPv4 tunnel backend
# Copyright (c) 2010 OpenWrt.org

# Hook into scan_interfaces() to synthesize a .device option
# This is needed for /sbin/ifup to properly dispatch control
# to setup_interface_6in4() even if no .ifname is set in
# the configuration.
scan_6in4() {
	config_set "$1" device "6in4-$1"
}

coldplug_interface_6in4() {
	setup_interface_6in4 "6in4-$1" "$1"
}

setup_interface_6in4() {
	local iface="$1"
	local cfg="$2"
	local link="6in4-$cfg"

	local local4
	config_get local4 "$cfg" ipaddr

	local remote4
	config_get remote4 "$cfg" peeraddr

	local local6
	config_get local6 "$cfg" ip6addr

	local mtu
	config_get mtu "$cfg" mtu

	local ttl
	config_get ttl "$cfg" ttl

	local defaultroute
	config_get_bool defaultroute "$cfg" defaultroute 1


	# creating the tunnel below will trigger a net subsystem event
	# prevent it from touching or iface by disabling .auto here
	uci_set_state network "$cfg" ifname $link
	uci_set_state network "$cfg" auto 0

	ip tunnel add $link mode sit remote $remote4 local $local4 ttl 255
	ip link set $link up
	ip link set mtu ${mtu:-1280} dev $link
	ip tunnel change $link ttl ${ttl:-64}
	ip addr add $local6 dev $link

	uci_set_state network "$cfg" ip6addr $local6

	[ "$defaultroute" = 1 ] && {
		ip -6 route add ::/0 dev $link
		uci_set_state network "$cfg" defaultroute 1
	}

	env -i ACTION="ifup" INTERFACE="$cfg" DEVICE="$link" PROTO=6in4 /sbin/hotplug-call "iface" &
}

stop_interface_6in4() {
	local cfg="$1"
	local link="6in4-$cfg"

	local local6=$(uci_get_state network "$cfg" ip6addr)
	local defaultroute=$(uci_get_state network "$cfg" defaultroute)

	grep -qs "^ *$link:" /proc/net/dev && {
		env -i ACTION="ifdown" INTERFACE="$cfg" DEVICE="$link" PROTO=6in4 /sbin/hotplug-call "iface" &

		[ "$defaultroute" = "1" ] && {
			ip -6 route del ::/0 dev $link
		}

		ip addr del $local6 dev $link
		ip link set $link down
		ip tunnel del $link
	}
}