Bash script with completion to connect to VPNs using TOTP passwords on MacOS

vpn

#!/usr/bin/env bash

config_file="${config_file:-$HOME/vpn.conf}"
if [ ! -f $config_file ]; then
	echo "could not find config file at $config_file"
	exit 1
fi

username=$(grep -m1 username <$config_file | awk -F\= '{print $2}')
if [ -z "$username" ]; then
	echo "username not set in config file"
	exit 1
fi

totp_key=$(grep -m1 totp_key <$config_file | awk -F\= '{print $2}')
if [ -z "$totp_key" ]; then
	echo "totp key not set in config file"
	exit 1
fi

old_ifs=$IFS
IFS=$'\n'
vpns=($(grep vpn <$config_file | awk -F\= '{print $2}'))
IFS=$old_ifs
if [ ${#vpns[@]} -eq 0 ]; then
	echo "no vpns specified in config file"
	exit 1
fi

list_vpns() {
	for vpn in "${vpns[@]}"; do
		echo $vpn
	done
}

connect_vpn() {
	if [ -z "$1" ]; then
		echo "usage: $(basename $0) connect vpn-name"
		exit 1
	fi

	vpn_name=$1
	xauth_key=$(security find-generic-password -l "$vpn_name" | grep svce | awk -F\" '{print $4}')
	if [ -z "$xauth_key" ]; then
		echo "Profile not found!"
		exit 1
	fi
	otp=$(/usr/local/bin/oathtool --totp -b -d 6 "$totp_key")
	security add-generic-password -a "$username" -s "$xauth_key" -w "$otp" -D "IPSec XAuth Password" -l "$vpn_name" -U

	connAction=\"$2\"
	connName=\"$vpn_name\"
	/usr/bin/env osascript >/dev/null <<-EOF
		tell application "System Events"
		  tell process "SystemUIServer"
		    set vpnMenu to (menu bar item 1 of menu bar 1 where description is "VPN")
		    tell vpnMenu to click
		    if ($connAction as string = "connect") then
		      try
		        click menu item ("Connect " & ${connName}) of menu 1 of vpnMenu
		      on error errMsg
		        display dialog "ERROR: Profile not found or already connected!"
		        key code 53
		        error number -128
		      end try
		      delay 2
		    else if ($connAction = "disconnect") then
		      try
		        click menu item ("Disconnect " & ${connName}) of menu 1 of vpnMenu
		      on error errMsg
		        display dialog "ERROR: Profile not found or already disconnected!"
		        key code 53
		        error number -128
		      end try
		      delay 2
		    end if
		  end tell
		end tell
	EOF
}

case "$1" in
	"list")
		list_vpns
		;;
	"connect")
		connect_vpn "$2" connect
		;;
	"disconnect")
		connect_vpn "$2" disconnect
		;;
	*)
		printf "usage:\n $(basename $0) list\n $(basename $0) connect vpn-name\n"
		exit 1
		;;
esac

vpn.bash_completion

# vpn(1) completion

_vpn() {
    # based on https://stackoverflow.com/a/17881946
    local cur prev

    cur=${COMP_WORDS[COMP_CWORD]}
    prev=${COMP_WORDS[COMP_CWORD - 1]}

    case ${COMP_CWORD} in
        1)
            COMPREPLY=($(compgen -W "list connect disconnect" -- ${cur}))
            ;;
        2)
            case ${prev} in
                connect) ;&

                disconnect)
                    # based on https://stackoverflow.com/a/40944195
                    mapfile -t patterns < <(vpn list)
                    mapfile -t COMPREPLY < <(compgen -W "$(printf '%q ' "${patterns[@]}")" -- "$cur" | awk '/ / { print "\""$0"\"" } /^[^ ]+$/ { print $0 }')
                    ;;
            esac
            ;;
        *)
            COMPREPLY=()
            ;;
    esac
}

complete -F _vpn vpn

vpn.conf

totp_key=abcdef0123456
username=my.username
vpn=A VPN Profile Name
vpn=Another VPN Profile Name