pifinder.sh

#!/bin/bash
# INSTALL: sudo wget <RAW link from gist here> -O /usr/bin/pifinder; chmod 755 /usr/bin/pifinder;
# USAGE: pifinder
#        pifinder 192.168.1.*
#        pifinder 192.168.*.*


# RPi Connect function
connect () {
	echo "Connecting to Raspberry Pi at $1 now..."
	ssh -q -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no pi@$1
}


# Get sudo if not
sudo ls 1> /dev/null


# Get subnet to scan
if [ $1 ]; then
	subnet=$1
else
	for line in $( ifconfig | grep -o "^[a-z0-9]\+" ); do
		_ip=`ipconfig getifaddr $line`
		if [ $_ip ]; then
			subnet=`echo $_ip | egrep -o "^[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}"`".*"
			break
		fi
	done
fi


# Search for Pi on subnet
if [[ ! -z "$subnet" ]]; then
	echo "Scanning subnet: $subnet"
	IPaddr=`sudo nmap -sP $subnet | grep -B 2 -e "(Raspberry Pi Foundation)" | egrep -o "[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}"`
else
	echo "ERROR: Could not find subnet to scan!"
	echo "Try $0 xxx.xxx.xxx.* where xxx.xxx.xxx is your subnet."
	exit
fi


# Split all found RPi IP addresses into an array
addrs=()
while read -r addr; do
	addrs+=("$addr")
done <<< "$IPaddr"


if [[ ${#addrs[@]} = 0 ]]; then
	echo "ERROR: Couldn't find a Raspberry Pi on subnet: $subnet"
	exit
elif [[ ${#addrs[@]} = 1 ]]; then
	# Connect to Pi at ${#addrs[0]}
	echo "Found one pi at ${#addrs[0]}"
else
	echo "Found ${#addrs[@]} Raspberry Pi's on subnet: $subnet"
	select addr in "${addrs[@]}"
	do
		if [[ -z "$addr" ]]; then
			echo "Invalid selection."
			continue
		else
			IP="$addr"
			break
		fi
	done
fi


# Connect to RPi at $IP
connect "$IP"