cdist/cdist/scan/scan.py

229 lines
7.2 KiB
Python

# -*- coding: utf-8 -*-
#
# 2020 Nico Schottelius (nico-cdist at schottelius.org)
#
# This file is part of cdist.
#
# cdist is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# cdist is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with cdist. If not, see <http://www.gnu.org/licenses/>.
#
#
from multiprocessing import Process
import os
import logging
from scapy.all import *
# Datetime overwrites scapy.all.datetime - needs to be imported AFTER
import datetime
import cdist.config
logging.basicConfig(level=logging.DEBUG)
log = logging.getLogger("scan")
datetime_format = '%Y-%m-%d %H:%M:%S'
class Host(object):
def __init__(self, addr, outdir, name_mapper=None):
self.addr = addr
self.workdir = os.path.join(outdir, addr)
self.name_mapper = name_mapper
os.makedirs(self.workdir, exist_ok=True)
def __get(self, key, default=None):
fname = os.path.join(self.workdir, key)
value = default
if os.path.isfile(fname):
with open(fname, "r") as fd:
value = fd.readline()
return value
def __set(self, key, value):
fname = os.path.join(self.workdir, key)
with open(fname, "w") as fd:
fd.write(f"{value}")
def name(self, default=None):
if self.name_mapper is None:
return default
fpath = os.path.join(os.getcwd(), self.name_mapper)
if os.path.isfile(fpath) and os.access(fpath, os.X_OK):
out = subprocess.run([fpath, self.addr], capture_output=True)
if out.returncode != 0:
return default
else:
value = out.stdout.decode()
return (default if len(value) == 0 else value)
else:
return default
def address(self):
return self.addr
def last_seen(self, default=None):
raw = self.__get('last_seen')
if raw:
return datetime.datetime.strptime(raw, datetime_format)
else:
return default
def last_configured(self, default=None):
raw = self.__get('last_configured')
if raw:
return datetime.datetime.strptime(raw, datetime_format)
else:
return default
def seen(self):
now = datetime.datetime.now().strftime(datetime_format)
self.__set('last_seen', now)
# XXX: There's no easy way to use the config module without feeding it with
# CLI args. Might as well call everything from scratch!
def configure(self):
target = self.name() or self.address()
cmd = ['cdist', 'config', '-v', target]
fname = os.path.join(self.workdir, 'last_configuration_log')
with open(fname, "w") as fd:
log.debug("Executing: %s", cmd)
completed_process = subprocess.run(cmd, stdout=fd, stderr=fd)
if completed_process.returncode != 0:
log.error("%s return with non-zero code %i - see %s for \
details.", cmd, completed_process.returncode, fname)
now = datetime.datetime.now().strftime(datetime_format)
self.__set('last_configured', now)
class Trigger(object):
"""
Trigger an ICMPv6EchoReply from all hosts that are alive
"""
def __init__(self, interfaces, sleeptime, verbose=False):
self.interfaces = interfaces
# Used by scapy / send in trigger/2.
self.verbose = verbose
# Delay in seconds between sent ICMPv6EchoRequests.
self.sleeptime = sleeptime
def start(self):
self.processes = []
for interface in self.interfaces:
p = Process(target=self.run_interface, args=(interface,))
self.processes.append(p)
p.start()
def join(self):
for process in self.processes:
process.join()
def run_interface(self, interface):
while True:
self.trigger(interface)
time.sleep(self.sleeptime)
def trigger(self, interface):
try:
log.debug("Sending ICMPv6EchoRequest on %s", interface)
packet = IPv6(
dst="ff02::1%{}".format(interface)
) / ICMPv6EchoRequest()
send(packet, verbose=self.verbose)
except Exception as e:
log.error("Could not send ICMPv6EchoRequest: %s", e)
class Scanner(object):
"""
Scan for replies of hosts, maintain the up-to-date database
"""
def __init__(self, interfaces, autoconfigure=False, outdir=None,
name_mapper=None):
self.interfaces = interfaces
self.autoconfigure = autoconfigure
self.name_mapper = name_mapper
self.config_delay = datetime.timedelta(seconds=3600)
if outdir:
self.outdir = outdir
else:
self.outdir = os.path.join(os.environ['HOME'], '.cdist', 'scan')
os.makedirs(self.outdir, exist_ok=True)
self.running_configs = {}
def handle_pkg(self, pkg):
if ICMPv6EchoReply in pkg:
host = Host(pkg['IPv6'].src, self.outdir, self.name_mapper)
if host.name():
log.verbose("Host %s (%s) is alive", host.name(),
host.address())
else:
log.verbose("Host %s is alive", host.address())
host.seen()
# Configure if needed.
if self.autoconfigure and \
host.last_configured(default=datetime.datetime.min) + \
self.config_delay < datetime.datetime.now():
self.config(host)
def list(self):
hosts = []
for addr in os.listdir(self.outdir):
hosts.append(Host(addr, self.outdir, self.name_mapper))
return hosts
def config(self, host):
if host.name() is None:
log.debug("config - could not resolve name for %s, aborting.",
host.address())
return
previous_config_process = self.running_configs.get(host.name())
if previous_config_process is not None and \
previous_config_process.is_alive():
log.debug("config - is already running for %s, aborting.",
host.name())
log.info("config - running against host %s (%s).", host.name(),
host.address())
p = Process(target=host.configure())
p.start()
self.running_configs[host.name()] = p
def start(self):
self.process = Process(target=self.scan)
self.process.start()
def join(self):
self.process.join()
def scan(self):
log.debug("Scanning - zzzzz")
try:
sniff(iface=self.interfaces,
filter="icmp6",
prn=self.handle_pkg)
except Exception as e:
log.error("Could not start listener: %s", e)