from .Interface import Interface import socketserver import threading import netifaces import platform import socket import time import sys import os import RNS class HDLC(): FLAG = 0x7E ESC = 0x7D ESC_MASK = 0x20 @staticmethod def escape(data): data = data.replace(bytes([HDLC.ESC]), bytes([HDLC.ESC, HDLC.ESC^HDLC.ESC_MASK])) data = data.replace(bytes([HDLC.FLAG]), bytes([HDLC.ESC, HDLC.FLAG^HDLC.ESC_MASK])) return data class ThreadingTCPServer(socketserver.ThreadingMixIn, socketserver.TCPServer): pass class TCPClientInterface(Interface): RECONNECT_WAIT = 5 RECONNECT_MAX_TRIES = None # TCP socket options TCP_USER_TIMEOUT = 20 TCP_PROBE_AFTER = 5 TCP_PROBE_INTERVAL = 3 TCP_PROBES = 5 def __init__(self, owner, name, target_ip=None, target_port=None, connected_socket=None, max_reconnect_tries=None): self.rxb = 0 self.txb = 0 self.IN = True self.OUT = False self.socket = None self.parent_interface = None self.name = name self.initiator = False self.reconnecting = False self.never_connected = True self.owner = owner self.writing = False self.online = False self.detached = False if max_reconnect_tries == None: self.max_reconnect_tries = TCPClientInterface.RECONNECT_MAX_TRIES else: self.max_reconnect_tries = max_reconnect_tries if connected_socket != None: self.receives = True self.target_ip = None self.target_port = None self.socket = connected_socket if platform.system() == "Linux": self.set_timeouts_linux() elif platform.system() == "Darwin": self.set_timeouts_osx() elif target_ip != None and target_port != None: self.receives = True self.target_ip = target_ip self.target_port = target_port self.initiator = True if not self.connect(initial=True): thread = threading.Thread(target=self.reconnect) thread.setDaemon(True) thread.start() else: thread = threading.Thread(target=self.read_loop) thread.setDaemon(True) thread.start() self.wants_tunnel = True def set_timeouts_linux(self): self.socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_USER_TIMEOUT, int(TCPClientInterface.TCP_USER_TIMEOUT * 1000)) self.socket.setsockopt(socket.SOL_SOCKET, socket.SO_KEEPALIVE, 1) self.socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_KEEPIDLE, int(TCPClientInterface.TCP_PROBE_AFTER)) self.socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_KEEPINTVL, int(TCPClientInterface.TCP_PROBE_INTERVAL)) self.socket.setsockopt(socket.IPPROTO_TCP, socket.TCP_KEEPCNT, int(TCPClientInterface.TCP_PROBES)) def set_timeouts_osx(self): if hasattr(socket, "TCP_KEEPALIVE"): TCP_KEEPIDLE = socket.TCP_KEEPALIVE else: TCP_KEEPIDLE = 0x10 sock.setsockopt(socket.SOL_SOCKET, socket.SO_KEEPALIVE, 1) sock.setsockopt(socket.IPPROTO_TCP, TCP_KEEPIDLE, int(TCPClientInterface.TCP_PROBE_AFTER)) def detach(self): if self.socket != None: if hasattr(self.socket, "close"): if callable(self.socket.close): RNS.log("Detaching "+str(self), RNS.LOG_DEBUG) self.detached = True try: self.socket.shutdown(socket.SHUT_RDWR) except Exception as e: RNS.log("Error while shutting down socket for "+str(self)+": "+str(e)) try: self.socket.close() except Exception as e: RNS.log("Error while closing socket for "+str(self)+": "+str(e)) self.socket = None def connect(self, initial=False): try: self.socket = socket.socket(socket.AF_INET, socket.SOCK_STREAM) self.socket.connect((self.target_ip, self.target_port)) self.online = True except Exception as e: if initial: RNS.log("Initial connection for "+str(self)+" could not be established: "+str(e), RNS.LOG_ERROR) RNS.log("Leaving unconnected and retrying connection in "+str(TCPClientInterface.RECONNECT_WAIT)+" seconds.", RNS.LOG_ERROR) return False else: raise e if platform.system() == "Linux": self.set_timeouts_linux() elif platform.system() == "Darwin": self.set_timeouts_osx() self.online = True self.writing = False self.never_connected = False return True def reconnect(self): if self.initiator: if not self.reconnecting: self.reconnecting = True attempts = 0 while not self.online: time.sleep(TCPClientInterface.RECONNECT_WAIT) attempts += 1 if self.max_reconnect_tries != None and attempts > self.max_reconnect_tries: RNS.log("Max reconnection attempts reached for "+str(self), RNS.LOG_ERROR) self.teardown() break try: self.connect() except Exception as e: RNS.log("Connection attempt for "+str(self)+" failed: "+str(e), RNS.LOG_DEBUG) if not self.never_connected: RNS.log("Reconnected TCP socket for "+str(self)+".", RNS.LOG_INFO) self.reconnecting = False thread = threading.Thread(target=self.read_loop) thread.setDaemon(True) thread.start() RNS.Transport.synthesize_tunnel(self) else: RNS.log("Attempt to reconnect on a non-initiator TCP interface. This should not happen.", RNS.LOG_ERROR) raise IOError("Attempt to reconnect on a non-initiator TCP interface") def processIncoming(self, data): self.rxb += len(data) if hasattr(self, "parent_interface") and self.parent_interface != None: self.parent_interface.rxb += len(data) self.owner.inbound(data, self) def processOutgoing(self, data): if self.online: while self.writing: time.sleep(0.01) try: self.writing = True data = bytes([HDLC.FLAG])+HDLC.escape(data)+bytes([HDLC.FLAG]) self.socket.sendall(data) self.writing = False self.txb += len(data) if hasattr(self, "parent_interface") and self.parent_interface != None: self.parent_interface.txb += len(data) except Exception as e: RNS.log("Exception occurred while transmitting via "+str(self)+", tearing down interface", RNS.LOG_ERROR) RNS.log("The contained exception was: "+str(e), RNS.LOG_ERROR) self.teardown() def read_loop(self): try: in_frame = False escape = False data_buffer = b"" while True: data_in = self.socket.recv(4096) if len(data_in) > 0: pointer = 0 while pointer < len(data_in): byte = data_in[pointer] pointer += 1 if (in_frame and byte == HDLC.FLAG): in_frame = False self.processIncoming(data_buffer) elif (byte == HDLC.FLAG): in_frame = True data_buffer = b"" elif (in_frame and len(data_buffer) < RNS.Reticulum.MTU): if (byte == HDLC.ESC): escape = True else: if (escape): if (byte == HDLC.FLAG ^ HDLC.ESC_MASK): byte = HDLC.FLAG if (byte == HDLC.ESC ^ HDLC.ESC_MASK): byte = HDLC.ESC escape = False data_buffer = data_buffer+bytes([byte]) else: self.online = False if self.initiator and not self.detached: RNS.log("TCP socket for "+str(self)+" was closed, attempting to reconnect...", RNS.LOG_WARNING) self.reconnect() else: RNS.log("TCP socket for remote client "+str(self)+" was closed.", RNS.LOG_VERBOSE) self.teardown() break except Exception as e: self.online = False RNS.log("An interface error occurred for "+str(self)+", the contained exception was: "+str(e), RNS.LOG_WARNING) if self.initiator: RNS.log("Attempting to reconnect...", RNS.LOG_WARNING) self.reconnect() else: self.teardown() def teardown(self): if self.initiator and not self.detached: RNS.log("The interface "+str(self)+" experienced an unrecoverable error and is being torn down. Restart Reticulum to attempt to open this interface again.", RNS.LOG_ERROR) if RNS.Reticulum.panic_on_interface_error: RNS.panic() else: RNS.log("The interface "+str(self)+" is being torn down.", RNS.LOG_VERBOSE) self.online = False self.OUT = False self.IN = False if hasattr(self, "parent_interface") and self.parent_interface != None: self.parent_interface.clients -= 1 if self in RNS.Transport.interfaces: if not self.initiator: RNS.Transport.interfaces.remove(self) def __str__(self): return "TCPInterface["+str(self.name)+"/"+str(self.target_ip)+":"+str(self.target_port)+"]" class TCPServerInterface(Interface): @staticmethod def get_address_for_if(name): return netifaces.ifaddresses(name)[netifaces.AF_INET][0]['addr'] def get_broadcast_for_if(name): return netifaces.ifaddresses(name)[netifaces.AF_INET][0]['broadcast'] def __init__(self, owner, name, device=None, bindip=None, bindport=None): self.rxb = 0 self.txb = 0 self.online = False self.clients = 0 self.IN = True self.OUT = False self.name = name if device != None: bindip = TCPServerInterface.get_address_for_if(device) if (bindip != None and bindport != None): self.receives = True self.bind_ip = bindip self.bind_port = bindport def handlerFactory(callback): def createHandler(*args, **keys): return TCPInterfaceHandler(callback, *args, **keys) return createHandler self.owner = owner address = (self.bind_ip, self.bind_port) ThreadingTCPServer.allow_reuse_address = True self.server = ThreadingTCPServer(address, handlerFactory(self.incoming_connection)) thread = threading.Thread(target=self.server.serve_forever) thread.setDaemon(True) thread.start() self.online = True def incoming_connection(self, handler): RNS.log("Accepting incoming TCP connection", RNS.LOG_VERBOSE) interface_name = "Client on "+self.name spawned_interface = TCPClientInterface(self.owner, interface_name, target_ip=None, target_port=None, connected_socket=handler.request) spawned_interface.OUT = self.OUT spawned_interface.IN = self.IN spawned_interface.target_ip = handler.client_address[0] spawned_interface.target_port = str(handler.client_address[1]) spawned_interface.parent_interface = self spawned_interface.online = True RNS.log("Spawned new TCPClient Interface: "+str(spawned_interface), RNS.LOG_VERBOSE) RNS.Transport.interfaces.append(spawned_interface) self.clients += 1 spawned_interface.read_loop() def processOutgoing(self, data): pass def __str__(self): return "TCPServerInterface["+self.name+"/"+self.bind_ip+":"+str(self.bind_port)+"]" class TCPInterfaceHandler(socketserver.BaseRequestHandler): def __init__(self, callback, *args, **keys): self.callback = callback socketserver.BaseRequestHandler.__init__(self, *args, **keys) def handle(self): self.callback(handler=self)