Raspberry Pi Wi-Fi join script

wifijoin.sh

#!/bin/bash
# Raspbian Wi-Fi connect script
# You can scan [1], connect directly [2], rejoin [3] or view the configuration file [4] with this little script I wrote just for fun and I thought I'd share it :-)
# Tested on Raspberry Pi Zero w

if [ "$(id -u)" != "0" ] ; then
	echo "Please run this script as superuser"
	exit 1
fi

if [ -z "$(which wpa_cli)" ] ; then
	echo "wpa_cli: not found. Exiting."
	exit 1
fi
if [ "$1" == "-h" ] || [ "$1" == "--help" ] ; then
	echo -e "Raspbian Wi-Fi connect script: no options yet"
fi

ConnectToSSID() {
	SSID=${1}
	PASSWORD=${2:-'key_mgmt=NONE'}
	CONFIG="/etc/wpa_supplicant/wpa_supplicant.conf"

	if [ ! -z "$isEncrypted" ] ; then
		NETWORK="$(wpa_passphrase "${SSID}" "${PASSWORD}" | grep -v "#psk")"
	else
		NETWORK="network={\n	ssid="\""${SSID}"\""\n	"psk=\"${PASSWORD}\""\n}"
	fi

	if [ ! -z "$(cat /etc/wpa_supplicant/wpa_supplicant.conf | grep "$SSID")" ] ; then
		while : ; do
			echo -ne "This network is already added to the configuration\nAdd it again? [y\N]: " #TODO: add option to replace old SSID lines
			read redo
			case "$redo" in
				y|Y)
					break
					;;
				n|N|"")
					exit
					;;
				*)
					continue
					;;
			esac
		done
	fi

	echo -e "$NETWORK" >> $CONFIG
}

CheckWPA() {
	if [ ! -z "$(iwlist wlan0 scan | sed -nE "/$1/,/SSID/p" | grep WPA)" ] ; then
		echo -ne "It seems like this network is password protected (NOTE: this script doesn't checks if the password is correct). Please type the password: "
		while : ; do
			read -s wifipassword
			if [ ${#wifipassword} -lt 8 ] ; then
				echo "\nThe password should be 8 or more characters"
				continue
			fi
			echo -ne "\nDo you want to store the password encrypted only?: [Y/n]: "
			read enc
			case "$enc" in
				y|Y|"")
					isEncrypted=true
					;&
				n|N)
					return
					;;
				*)
					continue
					;;
			esac
		done
	fi
}

ScanWifi() { #TODO: refine WPA detection
	while : ; do
		echo "These are the available SSIDs"
		iwlist wlan0 scan | grep SSID
		echo -ne "Type the SSID to connect or press RETURN for rescan: "
		read option
		if [ ! -z "$option" ] ; then
			return
		fi
	done
}

while : ; do
	echo -ne "Please select:\n	Scan for active Wi-Fi routers [1]\n	Type SSID to connect [2]\n	Rejoin [3]\n	View config file [4]\n	Exit [0]\n	Select: "
	read answer
	case "$answer" in
		1)
			ScanWifi
			;&
		2)
			if [ -z "$option" ] ; then
				echo -n "Type the SSID: "
				read option
			fi
			CheckWPA "$option"
			ConnectToSSID "$option" "$wifipassword"
			;&
		3)
			wpa_cli -i wlan0 reconfigure
			;&
		0)
			exit
			;;
		4)
			cat /etc/wpa_supplicant/wpa_supplicant.conf
			continue
			;;
		*)
			echo "Please select: "
			;;
	esac
done