6in4: - support to automatically determine the local endpoint address from the current IPv4 default gateway - support updating the tunnel endpoint for he.net

SVN-Revision: 21612

1 files changed, 39 insertions, 15 deletions

diff --git a/package/6in4/files/6in4.sh b/package/6in4/files/6in4.sh
index 68a00edd86..5e416ee0bd 100755
--- a/package/6in4/files/6in4.sh
+++ b/package/6in4/files/6in4.sh
@@ -1,6 +1,16 @@
 # 6in4.sh - IPv6-in-IPv4 tunnel backend
 # Copyright (c) 2010 OpenWrt.org
 
+find_6in4_wanif() {
+	local if=$(ip -4 r l e 0/0); if="${if#default via * dev }"; if="${if%% *}"
+	[ -n "$if" ] && grep -qs "^ *$if:" /proc/net/dev && echo "$if"
+}
+
+find_6in4_wanip() {
+	local ip=$(ip -4 a s dev "$1"); ip="${ip#*inet }"
+	echo "${ip%%/[0-9]* brd *}"
+}
+
 # Hook into scan_interfaces() to synthesize a .device option
 # This is needed for /sbin/ifup to properly dispatch control
 # to setup_interface_6in4() even if no .ifname is set in
@@ -36,26 +46,40 @@ setup_interface_6in4() {
 	local defaultroute
 	config_get_bool defaultroute "$cfg" defaultroute 1
 
+	# If local4 is unset, guess local IPv4 address from the
+	# interface used by the default route.
+	[ -z "$local4" ] && {
+		local wanif=$(find_6in4_wanif)
+		[ -n "$wanif" ] && {
+			local4=$(find_6in4_wanip "$wanif")
+			uci_set_state network "$cfg" wan_device "$wanif"
+		}
+	}
 
-	# 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
+	[ -n "$local4" ] && {
+		# creating the tunnel below will trigger a net subsystem event
+		# prevent it from touching or iface by disabling .auto here
+		uci_set_state network "$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
+		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 $local6
+		uci_set_state network "$cfg" ipaddr $local4
+		uci_set_state network "$cfg" ip6addr $local6
 
-	[ "$defaultroute" = 1 ] && {
-		ip -6 route add ::/0 dev $link
-		uci_set_state network "$cfg" defaultroute 1
-	}
+		[ "$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" &
+		env -i ACTION="ifup" INTERFACE="$cfg" DEVICE="$link" PROTO=6in4 /sbin/hotplug-call "iface" &
+	} || {
+		echo "Cannot determine local IPv4 address for 6in4 tunnel $cfg - skipping"
+	}
 }
 
 stop_interface_6in4() {