6to4

   1 #!/bin/bash -e
   2
   3 VERBOSE=1
   4 LOCAL_IF=ppp0
   5
   6 case "$1" in
   7     start)
   8         if [ -z "$LOCAL4" ]; then
   9             [ "$LOCAL_IF" ] || LOCAL_IF=ppp0
  10             LOCAL4=$(ip -o addr show $LOCAL_IF | awk '/inet/ { print $4 }')
  11             if [ -z "$LOCAL4" ]; then
  12                 echo "Cannot find the IP assigned to $LOCAL_IF"
  13                 exit 1
  14              fi
  15         fi
  16
  17         LOCAL6=$(printf "%x%02x:%x%02x\n" $(echo $LOCAL4 | sed -e 's/\./ /g'))
  18         LOCAL6="2002:$LOCAL6::1/48"
  19
  20         [ "$RELAY" ] || RELAY=192.88.99.1
  21
  22         if [ "$VERBOSE" ]; then
  23             echo "Local v4 address: $LOCAL4"
  24             echo "Local v6 address: $LOCAL6"
  25             echo "6to4 Relay address: $RELAY"
  26         fi
  27
  28         ip link  set sit0  up
  29         ip addr  add $LOCAL6  dev sit0
  30         ip route add 2000::/3  via ::$RELAY
  31         ;;
  32     stop)
  33         ip link  set sit0  down
  34         ;;
  35     *)
  36         echo "Usage: $0 {start|stop}"
  37         exit 1
  38         ;;
  39 esac
  40
  41 exit 0
  42