ZeroTier VPN Switch Script

ztvpn.sh

#!/bin/bash

ZT_NETWORK="NETWORK_ID"

# colors
RCol='\033[0m'    # Text Reset
LGra='\033[0;37m';
Red='\033[0;31m';
Gre='\033[0;32m'; 
Yel='\033[0;33m'; 

display_usage() {
    echo -e "\nThis script enables / disables the ZeroTier gateway for this device on network $ZT_NETWORK \n\n"
    echo -e "Usage:\n    $0 <command> | --help\n"
    echo -e "Commands:\n"
    echo -e "    (e)nable\tEnables the VPN functionality\n"
    echo -e "    (d)isable\tDisables the VPN functionality\n"
    echo -e "    (s)tatus\tShows the status of the VPN network\n"
}

# check if the zerotier-cli binary is installed
command -v zerotier-cli >/dev/null 2>&1 || \
	{ echo -e >&2 "This script requires ${Yel}zerotier-cli${RCol} to run, but it's not installed. Aborting."; \
	  echo -e >&2 "You can install ZeroTier One by running:\n    ${LGra}curl -s https://install.zerotier.com/ | bash${RCol}";
	  exit 2; 
	}

# ask for the network ID the user wants to join
if [ $ZT_NETWORK == "NETWORK_ID" ]; then
	echo -e "You haven't configured a ZeroTier network for this script yet."

	while true; do
	    read -p "Please enter the network ID you whish to use: " ZT_NETWORK

	    if [ -z $ZT_NETWORK ] 
    	then true;
    	else
	    	break
	    fi;
    done

    echo -en "\nTo avoid being asked this again in the future, please edit this cript by setting the "
    echo -e "ZT_NETWORK variable to your desired network ID.\n"
fi

# check if we're connected to the correct ZT network
if zerotier-cli listnetworks | grep -Fq $ZT_NETWORK
then true # we're connected - so do nothing, just here for portability
else
    echo -e >&2 "Oops! Looks like you're not connected to network ${Gre}$ZT_NETWORK${RCol}"
    echo -e >&2 "Please connect first by running:"
    echo -e >&2 "    ${LGra}zerotier-cli join $ZT_NETWORK${RCol}"
    exit 3
fi

# validate arguments
while [[ $# -gt 0 ]]
do
	key="$1"

	case $key in
	    e|enable|-e|--enable)
	    ZT_ALLOW=1
	    shift # past argument
	    ;;
	    d|disable|-d|--disable)
	    ZT_ALLOW=0
	    shift # past argument
	    ;;
	    s|status|-s|--status)
	    zerotier-cli /network/$ZT_NETWORK
	    exit 0
	    shift
	    ;;
	    *)
	    display_usage   # unknown option
	    exit 1
	    ;;
	esac
	shift # past argument or value
done

if [ -z $ZT_ALLOW ]; then 
    display_usage
    exit 1
fi

# enable / disable allowGlobal and allowDefault
zerotier-cli set $ZT_NETWORK allowGlobal=$ZT_ALLOW &> /dev/null
zerotier-cli set $ZT_NETWORK allowDefault=$ZT_ALLOW &> /dev/null

# show informative output
if [ $ZT_ALLOW -eq 0 ] || [ -z $ZT_ALLOW ]
then VERB="DISABLED"
else VERB="ENABLED"
fi

echo -e "The ZeroTier VPN was successfuly $VERB"