# -*- 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 . import socket import ipaddress from aiohttp.web import HTTPConflict from gns3server.config import Config import logging log = logging.getLogger(__name__) class PortManager: """ :param host: IP address to bind for console connections """ def __init__(self, host="127.0.0.1"): self._console_host = host self._udp_host = host self._used_tcp_ports = set() self._used_udp_ports = set() server_config = Config.instance().get_section_config("Server") remote_console_connections = server_config.getboolean("allow_remote_console") console_start_port_range = server_config.getint("console_start_port_range", 2000) console_end_port_range = server_config.getint("console_end_port_range", 5000) self._console_port_range = (console_start_port_range, console_end_port_range) udp_start_port_range = server_config.getint("udp_start_port_range", 10000) udp_end_port_range = server_config.getint("udp_end_port_range", 20000) self._udp_port_range = (udp_start_port_range, udp_end_port_range) if remote_console_connections: log.warning("Remote console connections are allowed") if ipaddress.ip_address(host).version == 6: self._console_host = "::" else: self._console_host = "0.0.0.0" else: self._console_host = host PortManager._instance = self @classmethod def instance(cls): """ Singleton to return only one instance of PortManager. :returns: instance of PortManager """ if not hasattr(cls, "_instance") or cls._instance is None: cls._instance = cls() return cls._instance @property def console_host(self): return self._console_host @console_host.setter def host(self, new_host): self._console_host = new_host @property def console_port_range(self): return self._console_port_range @console_host.setter def console_port_range(self, new_range): assert isinstance(new_range, tuple) self._console_port_range = new_range @property def udp_host(self): return self._udp_host @udp_host.setter def host(self, new_host): self._udp_host = new_host @property def udp_port_range(self): return self._udp_port_range @udp_host.setter def udp_port_range(self, new_range): assert isinstance(new_range, tuple) self._udp_port_range = new_range @staticmethod def find_unused_port(start_port, end_port, host="127.0.0.1", socket_type="TCP", ignore_ports=[]): """ Finds an unused port in a range. :param start_port: first port in the range :param end_port: last port in the range :param host: host/address for bind() :param socket_type: TCP (default) or UDP :param ignore_ports: list of port to ignore within the range """ if end_port < start_port: raise Exception("Invalid port range {}-{}".format(start_port, end_port)) if socket_type == "UDP": socket_type = socket.SOCK_DGRAM else: socket_type = socket.SOCK_STREAM last_exception = None for port in range(start_port, end_port + 1): if port in ignore_ports: continue try: if ":" in host: # IPv6 address support with socket.socket(socket.AF_INET6, socket_type) as s: s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) s.bind((host, port)) # the port is available if bind is a success else: with socket.socket(socket.AF_INET, socket_type) as s: s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) s.bind((host, port)) # the port is available if bind is a success return port except OSError as e: last_exception = e if port + 1 == end_port: break else: continue raise HTTPConflict(text="Could not find a free port between {} and {} on host {}, last exception: {}".format(start_port, end_port, host, last_exception)) def get_free_console_port(self): """ Get an available TCP console port and reserve it """ port = self.find_unused_port(self._console_port_range[0], self._console_port_range[1], host=self._console_host, socket_type="TCP", ignore_ports=self._used_tcp_ports) self._used_tcp_ports.add(port) return port def reserve_console_port(self, port): """ Reserve a specific TCP console port number :param port: TCP port number """ if port in self._used_tcp_ports: raise HTTPConflict(text="TCP port already {} in use on host".format(port, self._console_host)) self._used_tcp_ports.add(port) return port def release_console_port(self, port): """ Release a specific TCP console port number :param port: TCP port number """ if port in self._used_tcp_ports: self._used_tcp_ports.remove(port) def get_free_udp_port(self): """ Get an available UDP port and reserve it """ port = self.find_unused_port(self._udp_port_range[0], self._udp_port_range[1], host=self._udp_host, socket_type="UDP", ignore_ports=self._used_udp_ports) self._used_udp_ports.add(port) return port def reserve_udp_port(self, port): """ Reserve a specific UDP port number :param port: UDP port number """ if port in self._used_udp_ports: raise HTTPConflict(text="UDP port already {} in use on host".format(port, self._console_host)) self._used_udp_ports.add(port) def release_udp_port(self, port): """ Release a specific UDP port number :param port: UDP port number """ if port in self._used_udp_ports: self._used_udp_ports.remove(port)