Add new package for configuring 6rd tunnels.

This patch adds support for manually configuring 6rd tunnels. It depends on
the netifd patches I sent earlier, which add 6rd support.

A basic interface configuration looks like:

    config interface 'wan6'
      option proto '6rd'
      option peeraddr '192.0.2.1'
      option ip6prefix '2123::'
      option ip6prefixlen '16'
      option ip4prefixlen '0'

Where ip4prefixlen is optional and actually defaults to 0, which would use all
bits of the IPv4 in the calculated IPv6 subnet.

I believe it should be possible to configure a regular 6to4 tunnel using this,
and that we may want to merge the two eventually, but there are some larger

differences between the two at the moment:

 - 6rd addresses can be more difficult to calculate. My ISP, for example, has
   a setup with a v6 mask of 43 bits, and a v4 mask of 19.

 - 6to4 has support for configuring radvd. This is something we want, of
   course, but it seems best to deal with this in a separate patch.

Just creating a new package looked like the quickest way to get this in.

This work is based on the 6in4 package, and work by Stijn Tintel.

Signed-off-by: Stéphan Kochen <stephan@kochen.nl>

git-svn-id: svn://svn.openwrt.org/openwrt/trunk@32431 3c298f89-4303-0410-b956-a3cf2f4a3e73

1 files changed, 29 insertions, 0 deletions

diff --git a/package/6rd/files/6rd.hotplug b/package/6rd/files/6rd.hotplug
new file mode 100644
index 0000000000..f38526c53a
--- /dev/null
+++ b/package/6rd/files/6rd.hotplug
@@ -0,0 +1,29 @@
+#!/bin/sh
+
+if [ "$ACTION" = ifup ]; then
+	. /lib/functions.sh
+
+	INCLUDE_ONLY=1
+	. /lib/netifd/proto/6rd.sh
+
+	include /lib/network
+	scan_interfaces
+
+	update_tunnel() {
+		local cfg="$1"
+
+		local proto
+		config_get proto "$cfg" proto
+		[ "$proto" = 6rd ] || return 0
+
+		local wandev
+		config_get wandev "$cfg" wan_device "$(find_6rd_wanif)"
+		[ "$wandev" = "$DEVICE" ] || return 0
+
+		local wanip=$(find_6rd_wanip "$wandev")
+
+		[ -n "$wanip" ] && ifup "$cfg"
+	}
+
+	config_foreach update_tunnel interface
+fi