6to4: don't start if detected local IPv4 address is RFC1918, allows people to deploy...
[openwrt/openwrt.git] / package / 6to4 / files / 6to4.sh
index 65f4ffa5c2613f731f11f1fbd2b60f05b13907ea..6e85914b434190f72475647342dc6a984cf272f2 100755 (executable)
@@ -1,5 +1,5 @@
 # 6to4.sh - IPv6-in-IPv4 tunnel backend
-# Copyright (c) 2010 OpenWrt.org
+# Copyright (c) 2010-2011 OpenWrt.org
 
 find_6to4_wanif() {
        local if=$(ip -4 r l e 0.0.0.0/0); if="${if#default* dev }"; if="${if%% *}"
@@ -18,6 +18,15 @@ find_6to4_prefix() {
        printf "2002:%02x%02x:%02x%02x\n" $1 $2 $3 $4
 }
 
+test_6to4_rfc1918()
+{
+       local oIFS="$IFS"; IFS="."; set -- $1; IFS="$oIFS"
+       [ $1 -eq  10 ] && return 0
+       [ $1 -eq 192 ] && [ $2 -eq 168 ] && return 0
+       [ $1 -eq 172 ] && [ $2 -ge  16 ] && [ $2 -le  31 ] && return 0
+       return 1
+}
+
 set_6to4_radvd_interface() {
        local cfgid="$1"
        local lanif="${2:-lan}"
@@ -136,6 +145,11 @@ setup_interface_6to4() {
                }
        }
 
+       test_6to4_rfc1918 "$local4" && {
+               logger -t "$link" "Local wan ip $local4 is private - aborting"
+               return
+       }
+
        [ -n "$local4" ] && {
                logger -t "$link" "Starting ..."