core/homeassistant/components/device_tracker/nmap_tracker.py

163 lines
4.9 KiB
Python

"""
homeassistant.components.device_tracker.nmap
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Device tracker platform that supports scanning a network with nmap.
Configuration:
To use the nmap tracker you will need to add something like the following
to your config/configuration.yaml
device_tracker:
platform: nmap_tracker
hosts: 192.168.1.1/24
Variables:
hosts
*Required
The IP addresses to scan in the network-prefix notation (192.168.1.1/24) or
the range notation (192.168.1.1-255).
"""
import logging
from datetime import timedelta
from collections import namedtuple
import subprocess
import re
from libnmap.process import NmapProcess
from libnmap.parser import NmapParser, NmapParserException
import homeassistant.util.dt as dt_util
from homeassistant.const import CONF_HOSTS
from homeassistant.helpers import validate_config
from homeassistant.util import Throttle, convert
from homeassistant.components.device_tracker import DOMAIN
# Return cached results if last scan was less then this time ago
MIN_TIME_BETWEEN_SCANS = timedelta(seconds=5)
_LOGGER = logging.getLogger(__name__)
# interval in minutes to exclude devices from a scan while they are home
CONF_HOME_INTERVAL = "home_interval"
def get_scanner(hass, config):
""" Validates config and returns a Nmap scanner. """
if not validate_config(config, {DOMAIN: [CONF_HOSTS]},
_LOGGER):
return None
scanner = NmapDeviceScanner(config[DOMAIN])
return scanner if scanner.success_init else None
Device = namedtuple("Device", ["mac", "name", "ip", "last_update"])
def _arp(ip_address):
""" Get the MAC address for a given IP. """
cmd = ['arp', '-n', ip_address]
arp = subprocess.Popen(cmd, stdout=subprocess.PIPE)
out, _ = arp.communicate()
match = re.search(r'(([0-9A-Fa-f]{1,2}\:){5}[0-9A-Fa-f]{1,2})', str(out))
if match:
return match.group(0)
_LOGGER.info("No MAC address found for %s", ip_address)
return ''
class NmapDeviceScanner(object):
""" This class scans for devices using nmap """
def __init__(self, config):
self.last_results = []
self.hosts = config[CONF_HOSTS]
minutes = convert(config.get(CONF_HOME_INTERVAL), int, 0)
self.home_interval = timedelta(minutes=minutes)
self.success_init = True
self._update_info()
_LOGGER.info("nmap scanner initialized")
def scan_devices(self):
""" Scans for new devices and return a
list containing found device ids. """
self._update_info()
return [device.mac for device in self.last_results]
def get_device_name(self, mac):
""" Returns the name of the given device or None if we don't know. """
filter_named = [device.name for device in self.last_results
if device.mac == mac]
if filter_named:
return filter_named[0]
else:
return None
def _parse_results(self, stdout):
""" Parses results from an nmap scan.
Returns True if successful, False otherwise. """
try:
results = NmapParser.parse(stdout)
now = dt_util.now()
self.last_results = []
for host in results.hosts:
if host.is_up():
if host.hostnames:
name = host.hostnames[0]
else:
name = host.ipv4
if host.mac:
mac = host.mac
else:
mac = _arp(host.ipv4)
if mac:
device = Device(mac, name, host.ipv4, now)
self.last_results.append(device)
_LOGGER.info("nmap scan successful")
return True
except NmapParserException as parse_exc:
_LOGGER.error("failed to parse nmap results: %s", parse_exc.msg)
self.last_results = []
return False
@Throttle(MIN_TIME_BETWEEN_SCANS)
def _update_info(self):
""" Scans the network for devices.
Returns boolean if scanning successful. """
if not self.success_init:
return False
_LOGGER.info("Scanning")
options = "-F --host-timeout 5"
exclude_targets = set()
if self.home_interval:
now = dt_util.now()
for host in self.last_results:
if host.last_update + self.home_interval > now:
exclude_targets.add(host)
if len(exclude_targets) > 0:
target_list = [t.ip for t in exclude_targets]
options += " --exclude {}".format(",".join(target_list))
nmap = NmapProcess(targets=self.hosts, options=options)
nmap.run()
if nmap.rc == 0:
if self._parse_results(nmap.stdout):
self.last_results.extend(exclude_targets)
else:
self.last_results = []
_LOGGER.error(nmap.stderr)
return False