relatively quick script to find raspberry pis on your current network; built for macos, requires root

find-pis.sh

#!/usr/bin/env bash

# Find RaspberryPis on your network.
#
# Usage: ./find-pis.sh <iface:default en0>
#

# raspberry pi mac addresses
# source: https://maclookup.app/search/vendors/results?vendor=Raspberry+Pi
# - https://maclookup.app/vendors/raspberry-pi-foundation
# - https://maclookup.app/vendors/raspberry-pi-trading-ltd

PI_MAC_ADDRESS_LIST="3A:35:41|DC:A6:32|E4:5F:01|B8:27:EB"
SCRIPT_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"

set -ue

# default interface is wifi (en0 on mac)
iface="${1:-en0}"
data=$(ifconfig "$iface"|grep "inet ")

# find the ip address and mask of the given iface
ip=$(echo "$data"|cut -f 2 -d " ")
maskHex=$(echo "$data"|cut -f 4 -d " "|sed 's/^0x//')
# convert the hex into an ip address
mask=$(perl -wE "say join('.', map {hex(\$_)} unpack('A2 A2 A2 A2','${maskHex}'))")

# get the cidr from ip and mask
cidr=$(${SCRIPT_DIR}/get-cidr-from-ip-mask.pl "$ip" "$mask")

echo "Searching ${cidr}..."
results=$(sudo nmap -sn -n "$cidr" | awk "/^Nmap/{ip=\$NF}/${PI_MAC_ADDRESS_LIST}/{print ip}")

echo
echo "Found:"
echo $results

get-cidr-from-ip-mask.pl

#!/usr/bin/env perl -w

use strict;
use warnings 'all';
use feature 'say';

use NetAddr::IP;

my $net = NetAddr::IP->new($ARGV[0], $ARGV[1]);
if (!$net)
{
  say "bad arguments";
  exit;
}
say $net->network;