HostControl.py

# -*- coding: utf-8 -*-

# This file is part of python-opsi.
# Copyright (C) 2010-2017 uib GmbH <info@uib.de>

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.

# This program 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 Affero General Public License for more details.

# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
"""
HostControl backend.

This backend can be used to control hosts.

:copyright: uib GmbH <info@uib.de>
:author: Jan Schneider <j.schneider@uib.de>
:author: Erol Ueluekmen <e.ueluekmen@uib.de>
:author: Niko Wenselowski <n.wenselowski@uib.de>
:license: GNU Affero General Public License version 3
"""

import base64
import socket
import struct
import time

from contextlib import closing

try:
	from httplib import HTTPSConnection
except ImportError:
	# Python 3 compatibility
	from http.client import HTTPSConnection

from OPSI.Exceptions import BackendMissingDataError, BackendUnaccomplishableError
from OPSI.Logger import Logger, LOG_DEBUG
from OPSI.Types import (forceBool, forceDict, forceHostId, forceHostIdList,
						forceInt, forceIpAddress, forceList, forceUnicode,
						forceUnicodeList)
from OPSI.Backend.Backend import ExtendedBackend
from OPSI.Util import fromJson, toJson
from OPSI.Util.Thread import KillableThread
from OPSI.Util.HTTP import closingConnection, non_blocking_connect_https

__all__ = ('RpcThread', 'ConnectionThread', 'HostControlBackend')

logger = Logger()


def _configureHostcontrolBackend(backend, kwargs):
	"""
	Configure `backend` to the values given in `kwargs`.

	Keys in `kwargs` will be treated as lowercase.
	Supported keys are 'broadcastaddresses', 'hostrpctimeout', \
'maxconnections' opsiclientdport' and 'resolvehostaddress'.
	Unrecognized options will be ignored.

	:type backend: HostControlBackend or HostControlSafeBackend
	:type kwargs: dict
	"""
	for option, value in kwargs.items():
		option = option.lower()
		if option == 'opsiclientdport':
			backend._opsiclientdPort = forceInt(value)
		elif option == 'hostrpctimeout':
			backend._hostRpcTimeout = forceInt(value)
		elif option == 'resolvehostaddress':
			backend._resolveHostAddress = forceBool(value)
		elif option == 'maxconnections':
			backend._maxConnections = forceInt(value)
		elif option == 'broadcastaddresses':
			try:
				backend._broadcastAddresses = forceDict(value)
			except ValueError:
				# This is an old-style configuraton. Old default
				# port was 12287 so we assume this as the default
				# and convert everything to the new format.
				backend._broadcastAddresses = {bcAddress: (12287, ) for bcAddress in forceUnicodeList(value)}
				logger.warning(
					"Your hostcontrol backend configuration uses the old "
					"format for broadcast addresses. The new format "
					"allows to also set a list of ports to send the "
					"broadcast to.\nPlease use this new "
					"value in the future: {0!r}", backend._broadcastAddresses
				)

			newAddresses = {bcAddress: tuple(forceInt(port) for port in ports)
							for bcAddress, ports
							in backend._broadcastAddresses.items()}
			backend._broadcastAddresses = newAddresses

	if backend._maxConnections < 1:
		backend._maxConnections = 1


class RpcThread(KillableThread):
	def __init__(self, hostControlBackend, hostId, address, username, password, method, params=[], hostPort=0):
		KillableThread.__init__(self)
		self.hostControlBackend = hostControlBackend
		self.hostId = forceHostId(hostId)
		self.address = forceIpAddress(address)
		self.username = forceUnicode(username)
		self.password = forceUnicode(password)
		self.method = forceUnicode(method)
		self.params = forceList(params)
		self.error = None
		self.result = None
		self.started = 0
		self.ended = 0
		if hostPort:
			self.hostPort = forceInt(hostPort)
		else:
			self.hostPort = self.hostControlBackend._opsiclientdPort

	def run(self):
		self.started = time.time()
		timeout = self.hostControlBackend._hostRpcTimeout
		if timeout < 0:
			timeout = 0

		try:
			query = toJson(
				{
					'id': 1,
					'method': self.method,
					'params': self.params
				}
			).encode('utf-8')

			connection = HTTPSConnection(
				host=self.address,
				port=self.hostPort,
				timeout=timeout
			)
			with closingConnection(connection) as connection:
				non_blocking_connect_https(connection, timeout)
				connection.putrequest('POST', '/opsiclientd')
				connection.putheader('content-type', 'application/json')
				connection.putheader('content-length', str(len(query)))
				auth = u'{0}:{1}'.format(self.username, self.password)
				connection.putheader('Authorization', 'Basic ' + base64.b64encode(auth.encode('latin-1')))
				connection.endheaders()
				connection.send(query)

				response = connection.getresponse()
				response = response.read()
				response = fromJson(unicode(response, 'utf-8'))

				if response and isinstance(response, dict):
					self.error = response.get('error')
					self.result = response.get('result')
				else:
					self.error = u"Bad response from client: %s" % forceUnicode(response)
		except Exception as e:
			self.error = forceUnicode(e)
		finally:
			self.ended = time.time()


class ConnectionThread(KillableThread):
	def __init__(self, hostControlBackend, hostId, address):
		KillableThread.__init__(self)
		self.hostControlBackend = hostControlBackend
		self.hostId = forceHostId(hostId)
		self.address = forceIpAddress(address)
		self.result = False
		self.started = 0
		self.ended = 0

	def run(self):
		self.started = time.time()
		timeout = self.hostControlBackend._hostReachableTimeout
		if timeout < 0:
			timeout = 0

		logger.info(u"Trying connection to '%s:%d'" % (self.address, self.hostControlBackend._opsiclientdPort))
		try:
			conn = HTTPSConnection(
				host=self.address,
				port=self.hostControlBackend._opsiclientdPort,
				timeout=timeout
			)
			with closingConnection(conn) as conn:
				non_blocking_connect_https(conn, self.hostControlBackend._hostReachableTimeout)
				if conn:
					self.result = True
		except Exception as e:
			logger.logException(e, LOG_DEBUG)
			logger.debug(e)
		self.ended = time.time()


class HostControlBackend(ExtendedBackend):

	def __init__(self, backend, **kwargs):
		self._name = 'hostcontrol'

		ExtendedBackend.__init__(self, backend)

		self._opsiclientdPort = 4441
		self._hostRpcTimeout = 15
		self._hostReachableTimeout = 3
		self._resolveHostAddress = False
		self._maxConnections = 50
		self._broadcastAddresses = {"255.255.255.255": (7, 9, 12287)}

		_configureHostcontrolBackend(self, kwargs)

	def __repr__(self):
		try:
			return u'<{0}(resolveHostAddress={1!r}, maxConnections={2!r})>'.format(
				self.__class__.__name__, self._resolveHostAddress, self._maxConnections
			)
		except AttributeError:
			# Can happen during initialisation
			return u'<{0}()>'.format(self.__class__.__name__)

	def _getHostAddress(self, host):
		address = None
		if self._resolveHostAddress:
			try:
				address = socket.gethostbyname(host.id)
			except socket.error as lookupError:
				logger.debug2("Failed to lookup ip address for {0}: {1!r}", host.id, lookupError)
		if not address:
			address = host.ipAddress
		if not address and not self._resolveHostAddress:
			try:
				address = socket.gethostbyname(host.id)
			except socket.error:
				raise BackendUnaccomplishableError(u"Failed to resolve ip address for host '%s'" % host.id)
		if not address:
			raise BackendUnaccomplishableError(u"Failed to get ip address for host '%s'" % host.id)
		return address

	def _opsiclientdRpc(self, hostIds, method, params=[], timeout=None):
		if not hostIds:
			raise BackendMissingDataError(u"No matching host ids found")
		hostIds = forceHostIdList(hostIds)
		method = forceUnicode(method)
		params = forceList(params)
		if not timeout:
			timeout = self._hostRpcTimeout
		timeout = forceInt(timeout)

		result = {}
		rpcts = []
		for host in self._context.host_getObjects(id=hostIds):  # pylint: disable=maybe-no-member
			try:
				try:
					port = None
					configState = self._context.configState_getObjects(configId="opsiclientd.control_server.port", objectId=host.id)
					if configState:
						logger.notice("Custom Port for opsiclientd found %s" % type(int(configState[0].values[0])))
						port = int(configState[0].values[0])
				except Exception as e:
					logger.critical("Exception: %s" % e)
					pass
				address = self._getHostAddress(host)
				rpcts.append(
					RpcThread(
						hostControlBackend=self,
						hostId=host.id,
						hostPort=port,
						address=address,
						username=u'',
						password=host.opsiHostKey,
						method=method,
						params=params
					)
				)
			except Exception as e:
				result[host.id] = {"result": None, "error": forceUnicode(e)}

		runningThreads = 0
		while rpcts:
			newRpcts = []
			for rpct in rpcts:
				if rpct.ended:
					if rpct.error:
						logger.error(u"Rpc to host %s failed, error: %s" % (rpct.hostId, rpct.error))
						result[rpct.hostId] = {"result": None, "error": rpct.error}
					else:
						logger.info(u"Rpc to host %s successful, result: %s" % (rpct.hostId, rpct.result))
						result[rpct.hostId] = {"result": rpct.result, "error": None}
					runningThreads -= 1
					continue

				if not rpct.started:
					if runningThreads < self._maxConnections:
						logger.debug(u"Starting rpc to host %s" % rpct.hostId)
						rpct.start()
						runningThreads += 1
				else:
					timeRunning = time.time() - rpct.started
					if timeRunning >= timeout + 5:
						# thread still alive 5 seconds after timeout => kill
						logger.error(u"Rpc to host %s (address: %s) timed out after %0.2f seconds, terminating" % (rpct.hostId, rpct.address, timeRunning))
						result[rpct.hostId] = {"result": None, "error": u"timed out after %0.2f seconds" % timeRunning}
						if not rpct.ended:
							try:
								rpct.terminate()
							except Exception as e:
								logger.error(u"Failed to terminate rpc thread: %s" % e)
						runningThreads -= 1
						continue
				newRpcts.append(rpct)
			rpcts = newRpcts
			time.sleep(0.1)

		return result

	def hostControl_start(self, hostIds=[]):
		''' Switches on remote computers using WOL. '''
		hosts = self._context.host_getObjects(attributes=['hardwareAddress'], id=hostIds)  # pylint: disable=maybe-no-member
		result = {}
		for host in hosts:
			try:
				if not host.hardwareAddress:
					raise BackendMissingDataError(u"Failed to get hardware address for host '%s'" % host.id)

				mac = host.hardwareAddress.replace(':', '')
				data = ''.join(['FFFFFFFFFFFF', mac * 16])  # Pad the synchronization stream.

				# Split up the hex values and pack.
				payload = ''
				for i in range(0, len(data), 2):
					payload = ''.join([
						payload,
						struct.pack('B', int(data[i:i + 2], 16))])

				for broadcastAddress, targetPorts in self._broadcastAddresses.items():
					logger.debug(u"Sending data to network broadcast {0} [{1}]", broadcastAddress, data)

					for port in targetPorts:
						logger.debug("Broadcasting to port {0!r}", port)
						with closing(socket.socket(socket.AF_INET, socket.SOCK_DGRAM, socket.IPPROTO_UDP)) as sock:
							sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, True)
							sock.sendto(payload, (broadcastAddress, port))

				result[host.id] = {"result": "sent", "error": None}
			except Exception as error:
				logger.logException(error, LOG_DEBUG)
				result[host.id] = {"result": None, "error": forceUnicode(error)}
		return result

	def hostControl_shutdown(self, hostIds=[]):
		if not hostIds:
			raise BackendMissingDataError(u"No host ids given")
		hostIds = self._context.host_getIdents(id=hostIds, returnType='unicode')  # pylint: disable=maybe-no-member
		return self._opsiclientdRpc(hostIds=hostIds, method='shutdown', params=[])

	def hostControl_reboot(self, hostIds=[]):
		if not hostIds:
			raise BackendMissingDataError(u"No host ids given")
		hostIds = self._context.host_getIdents(id=hostIds, returnType='unicode')  # pylint: disable=maybe-no-member
		return self._opsiclientdRpc(hostIds=hostIds, method='reboot', params=[])

	def hostControl_fireEvent(self, event, hostIds=[]):
		event = forceUnicode(event)
		hostIds = self._context.host_getIdents(id=hostIds, returnType='unicode')  # pylint: disable=maybe-no-member
		return self._opsiclientdRpc(hostIds=hostIds, method='fireEvent', params=[event])

	def hostControl_showPopup(self, message, hostIds=[]):
		message = forceUnicode(message)
		hostIds = self._context.host_getIdents(id=hostIds, returnType='unicode')  # pylint: disable=maybe-no-member
		return self._opsiclientdRpc(hostIds=hostIds, method='showPopup', params=[message])

	def hostControl_uptime(self, hostIds=[]):
		hostIds = self._context.host_getIdents(id=hostIds, returnType='unicode')  # pylint: disable=maybe-no-member
		return self._opsiclientdRpc(hostIds=hostIds, method='uptime', params=[])

	def hostControl_getActiveSessions(self, hostIds=[]):
		hostIds = self._context.host_getIdents(id=hostIds, returnType='unicode')  # pylint: disable=maybe-no-member
		return self._opsiclientdRpc(hostIds=hostIds, method='getActiveSessions', params=[])

	def hostControl_opsiclientdRpc(self, method, params=[], hostIds=[], timeout=None):
		hostIds = self._context.host_getIdents(id=hostIds, returnType='unicode')  # pylint: disable=maybe-no-member
		return self._opsiclientdRpc(hostIds=hostIds, method=method, params=params, timeout=timeout)

	def hostControl_reachable(self, hostIds=[], timeout=None):
		hostIds = self._context.host_getIdents(id=hostIds, returnType='unicode')  # pylint: disable=maybe-no-member
		if not hostIds:
			raise BackendMissingDataError(u"No matching host ids found")
		hostIds = forceHostIdList(hostIds)

		if not timeout:
			timeout = self._hostReachableTimeout
		timeout = forceInt(timeout)

		result = {}
		threads = []
		for host in self._context.host_getObjects(id=hostIds):  # pylint: disable=maybe-no-member
			try:
				address = self._getHostAddress(host)
				threads.append(
					ConnectionThread(
						hostControlBackend=self,
						hostId=host.id,
						address=address
					)
				)
			except Exception as e:
				logger.debug("Problem found: '%s'" % e)
				result[host.id] = False

		runningThreads = 0
		while threads:
			newThreads = []
			for thread in threads:
				if thread.ended:
					result[thread.hostId] = thread.result
					runningThreads -= 1
					continue

				if not thread.started:
					if runningThreads < self._maxConnections:
						logger.debug(u"Trying to check host reachable %s" % thread.hostId)
						thread.start()
						runningThreads += 1
				else:
					timeRunning = time.time() - thread.started
					if timeRunning >= timeout + 5:
						# thread still alive 5 seconds after timeout => kill
						logger.error(u"Reachable check to host %s address %s timed out after %0.2f  seconds, terminating" % (thread.hostId, thread.address, timeRunning))
						result[thread.hostId] = False
						if not thread.ended:
							try:
								thread.terminate()
							except Exception as e:
								logger.error(u"Failed to terminate reachable thread: %s" % e)
						runningThreads -= 1
						continue
				newThreads.append(thread)
			threads = newThreads
			time.sleep(0.1)
		return result

	def hostControl_execute(self, command, hostIds=[], waitForEnding=True, captureStderr=True, encoding=None, timeout=300):
		command = forceUnicode(command)
		hostIds = self._context.host_getIdents(id=hostIds, returnType='unicode')  # pylint: disable=maybe-no-member
		return self._opsiclientdRpc(
			hostIds=hostIds, method='execute',
			params=[command, waitForEnding, captureStderr, encoding, timeout]
		)