Simple MAC address spoofing for Bash on OSX

Macycle

#!/opt/local/bin/bash
# Macycle expects a declared associateive array in RC file.
# # declare -A devices=(
# #     ['dev1']='aa:aa:aa:aa:aa:aa'
# #   ['dev2']='bb:bb:bb:bb:bb:bb' #etc
# # )
# #
# environment stuff
unset CDPATH
 
# load config file
if [ -f "${HOME}"/.macyclerc ]; then
  . "${HOME}"/.macyclerc
else
  echo "Configuration file is missing! Checking 'devices[]' array..."
  if [ "${#devices[@]}" -eq 0 ]; then
    echo "Device list is empty. Please try adding key-value pairs to 'devices[]' array."
    exit 65
  fi
  exit 0
fi
## test
key="${1}"
routeIP='8.8.8.8' # Google DNS.
networkInterface=$(route get "${routeIP}" | egrep -o '(interface.*en)[0-9]+' | cut -d' ' -f2)
 
[[ -z "${networkInterface}" ]] && exit 69;
#
function macycle(){
  if [ -z "${key}" ]
  then
    promptValue
  else
    if (("${#devices[$key]}" > 0))
        then
            sudo ifconfig "${networkInterface}" ether "${devices[$key]}"
            networksetup -setairportpower "${networkInterface}" off; networksetup -setairportpower "${networkInterface}" on
            echo "Now spoofing $key. Wait for network interface to powercycle."
        else
            printf "\e[31mbad choice\e[0m\n"
            promptValue
            exit 64
        fi
    fi
}
function promptValue() {
    printf "%b" "(\e[38;5;82mactive\e[0m) $(default)\n" | column -t
    for i in "${!devices[@]}"
    do
        printf '%7s\n' "${i} :  ${devices[$i]}"
    done | column -t
 
    while read -rp "Choose new MAC address: " val && [ -z "${val}" ]; do :; done
 
    if (("${#devices[$val]}" > 0))
    then
        key="${val}"
        macycle
    else
        printf "\e[31mbad choice\e[0m\n"
        exit 64
    fi
}
function default() {
  ifconfig "${networkInterface}" | grep ether | cut -d" " -f2
}
macycle && exit 0
## To Do
# for  improved LINUX support:
## http://xmodulo.com/spoof-mac-address-network-interface-linux.html
###################################
# Local Variables:
# firestarter: "gist -u edb5e9db9248cc5d7131 %p"
# End: