#! /usr/bin/env python3

# Search for IP clients on the current network.

# Only tested on Linux; requires ping or the Linux arguments for arp.

# ipsearch with no arguments uses ping; it takes a while but should be reliable.

# ipsearch -a uses arp only, which is fast but only shows

# hosts in the arp cache.

import sys

import subprocess

import socket

import fcntl

import struct

import re

try:

from arpreq import arpreq

except:

arpreq = None

try:

from mac_lookup import match_mac

except:

match_mac = None

def ping(host):

"""Ping a host by name or address.

return True if it answers, False otherwise.

"""

rv = subprocess.call(["ping", "-q", "-c", "1", "-W", "1", host],

stdout = subprocess.PIPE,

stderr = subprocess.PIPE)

if rv == 0:

return ""

return None

def arp(host):

"""Call arp -a on an address.

return True if it answers, False otherwise.

"""

# print("host", host)

proc = subprocess.Popen(["arp", "-a", host],

stdout = subprocess.PIPE,

stderr = subprocess.PIPE)

proc_out = proc.communicate()[0].strip()

# print("proc_out is '%s'" % proc_out)

if b"no match found" in proc_out:

# print("no match found, returning none")

return None

# else:

# print("'no match found' isn't in '%s'" % proc_out)

if b"<incomplete>" in proc_out:

return None

match = re.search(b'([0-9A-F]{2}[:-]){5}([0-9A-F]{2})', proc_out, re.I)

if match:

return match.group().decode("utf-8")

return None

def ip_addr(iface):

"""Get the IP address of the interface (e.g. eth0)

"""

s = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)

info = fcntl.ioctl(s.fileno(),

0x8915, # SIOCGIFADDR

struct.pack('256s', bytes(iface[:15], "utf-8")))

return socket.inet_ntoa(info[20:24])

def scan(iface="eth0", ping_fn=ping, ping_first=True):

myip = ip_addr(iface)

print("My IP is", myip, "on", iface)

mynetwork = '.'.join(myip.split('.')[0:3])

print("My network is", mynetwork)

fmt = "%16s %18s %12s %s"

for h in range(1, 255): # I know, it should adjust based on net class

hostip = "%s.%d" % (mynetwork, h)

if ping_first:

out = ping_fn(hostip)

if arpreq:

mac = arpreq(hostip)

else:

mac = arp(hostip)

if not mac:

continue

if match_mac:

oui = match_mac(mac)

else:

oui = ''

try:

hostname, blah1, blah2 = socket.gethostbyaddr(hostip)

except:

hostname = '?'

if hostip == myip:

print(fmt % (hostip, mac, hostname, oui), "(that's me)")

else:

print(fmt % (hostip, mac, hostname, oui))

if __name__ == "__main__":

def Usage():

print("""Usage: %s [-a] [-p]

-p: ping each host first, in case they weren't in the arp cache already

-a: Use arp -a to ping.

""" % sys.argv[0])

sys.exit(1)

ifaces = [ "eth0", "wlan0" ]

myip = None

for iface in ifaces:

try:

myip = ip_addr(iface)

break

except OSError:

continue

if not myip:

print("Couldn't find my IP address")

sys.exit(1)

try:

if len(sys.argv) > 1 and sys.argv[1].startswith("-a"):

scan(iface, arp)

elif len(sys.argv) > 1 and sys.argv[1].startswith("-p"):

scan(iface, ping_first=False)

elif len(sys.argv) > 1:

Usage()

else:

scan(iface)

except KeyboardInterrupt:

print("Interrupt")