# -*- coding: utf-8 -*- # # Copyright (C) 2015 GNS3 Technologies Inc. # # This program 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. # # 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 General Public License for more details. # # You should have received a copy of the GNU General Public License # along with this program. If not, see . """ Set up and run the server. """ import os import sys import signal import socket import json import ipaddress import asyncio import threading import aiohttp import aiohttp_cors import functools import time import atexit from .route import Route from .request_handler import RequestHandler from ..config import Config from ..compute import MODULES from ..compute.port_manager import PortManager from ..controller import Controller from ..version import __version__ # do not delete this import import gns3server.handlers import logging log = logging.getLogger(__name__) class WebServer: def __init__(self, host, port): self._host = host self._port = port self._loop = None self._handler = None self._start_time = time.time() self._port_manager = PortManager(host) self._running = False @staticmethod def instance(host=None, port=None): """ Singleton to return only one instance of Server. :returns: instance of Server """ if not hasattr(WebServer, "_instance") or WebServer._instance is None: assert host is not None assert port is not None WebServer._instance = WebServer(host, port) return WebServer._instance @asyncio.coroutine def _run_application(self, handler, ssl_context=None): try: server = yield from self._loop.create_server(handler, self._host, self._port, ssl=ssl_context) except OSError as e: log.critical("Could not start the server: {}".format(e)) self._loop.stop() return return server @asyncio.coroutine def shutdown_server(self): """ Cleanly shutdown the server. """ if self._handler: yield from self._handler.finish_connections() self._handler = None if Config.instance().get_section_config("Server").getboolean("controller"): yield from Controller.instance().close() for module in MODULES: log.debug("Unloading module {}".format(module.__name__)) m = module.instance() yield from m.unload() if self._port_manager.tcp_ports: log.warning("TCP ports are still used {}".format(self._port_manager.tcp_ports)) if self._port_manager.udp_ports: log.warning("UDP ports are still used {}".format(self._port_manager.udp_ports)) for task in asyncio.Task.all_tasks(): task.cancel() self._loop.stop() def _signal_handling(self): def signal_handler(signame, *args): log.warning("Server has got signal {}, exiting...".format(signame)) asyncio.async(self.shutdown_server()) signals = ["SIGTERM", "SIGINT"] if sys.platform.startswith("win"): signals.extend(["SIGBREAK"]) else: signals.extend(["SIGHUP", "SIGQUIT"]) for signal_name in signals: callback = functools.partial(signal_handler, signal_name) if sys.platform.startswith("win"): # add_signal_handler() is not yet supported on Windows signal.signal(getattr(signal, signal_name), callback) else: self._loop.add_signal_handler(getattr(signal, signal_name), callback) def _create_ssl_context(self, server_config): import ssl ssl_context = ssl.SSLContext(ssl.PROTOCOL_SSLv23) certfile = server_config["certfile"] certkey = server_config["certkey"] try: ssl_context.load_cert_chain(certfile, certkey) except FileNotFoundError: log.critical("Could not find the SSL certfile or certkey") raise SystemExit except ssl.SSLError as e: log.critical("SSL error: {}".format(e)) raise SystemExit log.info("SSL is enabled") return ssl_context @asyncio.coroutine def start_shell(self): try: from ptpython.repl import embed except ImportError: log.error("Unable to start a shell: the ptpython module must be installed!") return yield from embed(globals(), locals(), return_asyncio_coroutine=True, patch_stdout=True) def _exit_handling(self): """ Makes sure the asyncio loop is closed. """ def close_asyncio_loop(): loop = None try: loop = asyncio.get_event_loop() except AttributeError: pass if loop is not None: loop.close() atexit.register(close_asyncio_loop) def _udp_server_discovery(self): """ UDP multicast and broadcast server discovery (Linux only) """ import ctypes uint32_t = ctypes.c_uint32 in_addr_t = uint32_t class in_addr(ctypes.Structure): _fields_ = [('s_addr', in_addr_t)] class in_pktinfo(ctypes.Structure): _fields_ = [('ipi_ifindex', ctypes.c_int), ('ipi_spec_dst', in_addr), ('ipi_addr', in_addr)] IP_PKTINFO = 8 with socket.socket(socket.AF_INET, socket.SOCK_DGRAM) as sock: membership = socket.inet_aton("239.42.42.1") + socket.inet_aton("0.0.0.0") sock.setsockopt(socket.IPPROTO_IP, socket.IP_ADD_MEMBERSHIP, membership) sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) sock.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1) sock.setsockopt(socket.SOL_IP, IP_PKTINFO, 1) try: sock.bind(("", self._port)) except OSError as e: log.error("UDP server discovery could not bind on port {}: {}".format(self._port, e)) return log.info("UDP server discovery started on port {}".format(self._port)) while self._loop.is_running(): try: data, ancdata, _, address = sock.recvmsg(255, socket.CMSG_LEN(255)) except OSError as e: log.error("Error while receiving UDP server discovery request: {}".format(e)) continue cmsg_level, cmsg_type, cmsg_data = ancdata[0] if cmsg_level == socket.SOL_IP and cmsg_type == IP_PKTINFO: pktinfo = in_pktinfo.from_buffer_copy(cmsg_data) request_address = ipaddress.IPv4Address(memoryview(pktinfo.ipi_addr).tobytes()) receiving_interface = socket.if_indextoname(pktinfo.ipi_ifindex) log.debug("UDP server discovery request received on {} using {}".format(receiving_interface, request_address)) local_address = ipaddress.IPv4Address(memoryview(pktinfo.ipi_spec_dst).tobytes()) if self._host != "0.0.0.0" and self._host != str(local_address): log.debug("Ignoring UDP discovery request received on {} instead of {}".format(local_address, self._host)) continue server_info = {"version": __version__, "ip": str(local_address), "port": self._port} data = json.dumps(server_info) sock.sendto(data.encode(), address) log.debug("Sent server info to {}:{} {}".format(address[0], address[1], data)) time.sleep(1) # this is to prevent too many request to slow down the server log.debug("UDP server discovery stopped") def run(self): """ Starts the server. """ logger = logging.getLogger("asyncio") logger.setLevel(logging.ERROR) if sys.platform.startswith("win"): loop = asyncio.get_event_loop() # Add a periodic callback to give a chance to process signals on Windows # because asyncio.add_signal_handler() is not supported yet on that platform # otherwise the loop runs outside of signal module's ability to trap signals. def wakeup(): loop.call_later(0.5, wakeup) loop.call_later(0.5, wakeup) asyncio.set_event_loop(loop) server_config = Config.instance().get_section_config("Server") ssl_context = None if server_config.getboolean("ssl"): if sys.platform.startswith("win"): log.critical("SSL mode is not supported on Windows") raise SystemExit ssl_context = self._create_ssl_context(server_config) self._loop = asyncio.get_event_loop() # Asyncio will raise error if coroutine is not called self._loop.set_debug(True) if server_config.getboolean("controller"): asyncio.async(Controller.instance().load()) for key, val in os.environ.items(): log.debug("ENV %s=%s", key, val) app = aiohttp.web.Application() # Allow CORS for this domains cors = aiohttp_cors.setup(app, defaults={ # Default web server for web gui dev "http://127.0.0.1:8080": aiohttp_cors.ResourceOptions(expose_headers="*", allow_headers="*"), "http://localhost:8080": aiohttp_cors.ResourceOptions(expose_headers="*", allow_headers="*"), "http://gns3.github.io": aiohttp_cors.ResourceOptions(expose_headers="*", allow_headers="*") }) for method, route, handler in Route.get_routes(): log.debug("Adding route: {} {}".format(method, route)) cors.add(app.router.add_route(method, route, handler)) for module in MODULES: log.debug("Loading module {}".format(module.__name__)) m = module.instance() m.port_manager = self._port_manager log.info("Starting server on {}:{}".format(self._host, self._port)) self._handler = app.make_handler(handler=RequestHandler) server = self._run_application(self._handler, ssl_context) self._loop.run_until_complete(server) self._signal_handling() self._exit_handling() if server_config.getboolean("shell"): asyncio.async(self.start_shell()) if sys.platform.startswith("linux") and server_config.getboolean("server_discovery"): # UDP discovery is only supported on Linux udp_server_discovery = threading.Thread(target=self._udp_server_discovery, daemon=True) udp_server_discovery.start() try: self._loop.run_forever() except TypeError as e: # This is to ignore an asyncio.windows_events exception # on Windows when the process gets the SIGBREAK signal # TypeError: async() takes 1 positional argument but 3 were given log.warning("TypeError exception in the loop {}".format(e)) finally: if self._handler and self._loop.is_running(): self._loop.run_until_complete(self._handler.finish_connections()) server.close() if self._loop.is_running(): self._loop.run_until_complete(app.finish())