babel_start.sh

#!/bin/sh

address="$1"
id="$2"

if ! test -f "/tmp/babel-${id}.pid"; then
  echo "start babel on ${address} in ${id}"

  addr4() {
    local mac=$(cat "/sys/class/net/$1/address")
    IFS=':'; set $mac; unset IFS
    [ "$6" = "ff" -o "$6" = "00" ] && set $1 $2 $3 $4 $5 "01"
    printf "10.%d.%d.%d" 0x$4 0x$5 0x$6
  }

  addr6() {
    local mac=$(cat "/sys/class/net/$1/address")
    IFS=':'; set $mac; unset IFS
    printf fdef:17a0:ffb1:300:$(printf %02x $((0x$1 ^ 2)))$2:${3}ff:fe$4:$5$6
  }

  # babel needs the link local (fe80:*) and a regular IPv6 address
  ip link set "uplink" down
  ip link set "uplink" up
  #ip a a $(addr4 "uplink")/32 dev "uplink"
  ip a a $(addr6 "uplink")/64 dev "uplink"

  babeld -D -I "/tmp/babel-${id}.pid" "uplink"
else
  echo "babel already runs on ${address} in ${id}"
fi