Module lib.server.telnet

Telnet class

# Based on https://github.com/cpopp/MicroTelnetServer/blob/master/utelnet/utelnetserver.py
# Add user login
# pylint:disable=consider-using-f-string
# pylint:disable=consider-using-enumerate
""" Telnet class """
import socket
import sys
import uos
import server.server
import tools.logger
import tools.support
import tools.tasking

class TelnetServerInstance(tools.tasking.ServerInstance):
        """ Telnet server instance """
        def __init__(self, **kwargs):
                tools.tasking.ServerInstance.__init__(self, **kwargs)

        def start(self):
                """ Start server """
                port = self.kwargs.get("telnet_port",23)
                if tools.support.telnet():
                        # start listening for telnet connections on port 23
                        try:
                                Telnet.stop()
                                Telnet.server[0] = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
                                Telnet.server[0].setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
                                ai = socket.getaddrinfo("0.0.0.0", port)
                                addr = ai[0][4]
                                Telnet.server[0].bind(addr)
                                Telnet.server[0].listen(1)
                                Telnet.server[0].setsockopt(socket.SOL_SOCKET, 20, Telnet.accept)
                        except Exception as err:
                                tools.logger.syslog("Telnet unavailable '%s'"%str(err))
                return "Telnet", port

class Telnet:
        """ Telnet class connection """
        client = [None]
        server = [None]

        @staticmethod
        def accept(socket_server):
                """ Accept telnet connection """
                # Attach new clients to dupterm and
                # send telnet control characters to disable line mode
                # and stop local echoing
                Telnet.close_client()
                from server import telnetcore
                Telnet.client[0], remote_addr = socket_server.accept()
                tools.tasking.Tasks.slow_down()
                tools.logger.syslog("Telnet connected from : %s" % remote_addr[0])
                Telnet.client[0].setblocking(False)
                Telnet.client[0].setsockopt(socket.SOL_SOCKET, 20, uos.dupterm_notify)
                Telnet.client[0].sendall(bytes([255, 252, 34])) # dont allow line mode
                Telnet.client[0].sendall(bytes([255, 251, 1])) # turn off local echo
                uos.dupterm(telnetcore.TelnetWrapper(Telnet.client[0]))

        @staticmethod
        def close_client():
                """ Close the opened client """
                if Telnet.client[0]:
                        # close any previous clients
                        uos.dupterm(None)
                        Telnet.client[0].close()
                        Telnet.client[0] = None
                        try:
                                del sys.modules["server.telnetcore"]
                        except:
                                pass

        @staticmethod
        def stop():
                """ Stop telnet server """
                # pylint:disable=global-variable-not-assigned
                uos.dupterm(None)
                if Telnet.server[0]:
                        Telnet.server[0].close()
                        Telnet.server[0] = None
                Telnet.close_client()

        @staticmethod
        def start(**kwargs):
                """ Start telnet server """
                config = server.server.ServerConfig()
                config.load_create()
                # If telnet activated
                if config.telnet:
                        tools.tasking.Tasks.create_server(TelnetServerInstance(**kwargs))
                else:
                        tools.logger.syslog("Telnet disabled in config")

Classes

class Telnet

Telnet class connection

Expand source code

class Telnet:
        """ Telnet class connection """
        client = [None]
        server = [None]

        @staticmethod
        def accept(socket_server):
                """ Accept telnet connection """
                # Attach new clients to dupterm and
                # send telnet control characters to disable line mode
                # and stop local echoing
                Telnet.close_client()
                from server import telnetcore
                Telnet.client[0], remote_addr = socket_server.accept()
                tools.tasking.Tasks.slow_down()
                tools.logger.syslog("Telnet connected from : %s" % remote_addr[0])
                Telnet.client[0].setblocking(False)
                Telnet.client[0].setsockopt(socket.SOL_SOCKET, 20, uos.dupterm_notify)
                Telnet.client[0].sendall(bytes([255, 252, 34])) # dont allow line mode
                Telnet.client[0].sendall(bytes([255, 251, 1])) # turn off local echo
                uos.dupterm(telnetcore.TelnetWrapper(Telnet.client[0]))

        @staticmethod
        def close_client():
                """ Close the opened client """
                if Telnet.client[0]:
                        # close any previous clients
                        uos.dupterm(None)
                        Telnet.client[0].close()
                        Telnet.client[0] = None
                        try:
                                del sys.modules["server.telnetcore"]
                        except:
                                pass

        @staticmethod
        def stop():
                """ Stop telnet server """
                # pylint:disable=global-variable-not-assigned
                uos.dupterm(None)
                if Telnet.server[0]:
                        Telnet.server[0].close()
                        Telnet.server[0] = None
                Telnet.close_client()

        @staticmethod
        def start(**kwargs):
                """ Start telnet server """
                config = server.server.ServerConfig()
                config.load_create()
                # If telnet activated
                if config.telnet:
                        tools.tasking.Tasks.create_server(TelnetServerInstance(**kwargs))
                else:
                        tools.logger.syslog("Telnet disabled in config")

Class variables

var client

var server

Static methods

def accept(socket_server)

Accept telnet connection

Expand source code

@staticmethod
def accept(socket_server):
        """ Accept telnet connection """
        # Attach new clients to dupterm and
        # send telnet control characters to disable line mode
        # and stop local echoing
        Telnet.close_client()
        from server import telnetcore
        Telnet.client[0], remote_addr = socket_server.accept()
        tools.tasking.Tasks.slow_down()
        tools.logger.syslog("Telnet connected from : %s" % remote_addr[0])
        Telnet.client[0].setblocking(False)
        Telnet.client[0].setsockopt(socket.SOL_SOCKET, 20, uos.dupterm_notify)
        Telnet.client[0].sendall(bytes([255, 252, 34])) # dont allow line mode
        Telnet.client[0].sendall(bytes([255, 251, 1])) # turn off local echo
        uos.dupterm(telnetcore.TelnetWrapper(Telnet.client[0]))

def close_client()

Close the opened client

Expand source code

@staticmethod
def close_client():
        """ Close the opened client """
        if Telnet.client[0]:
                # close any previous clients
                uos.dupterm(None)
                Telnet.client[0].close()
                Telnet.client[0] = None
                try:
                        del sys.modules["server.telnetcore"]
                except:
                        pass

def start(**kwargs)

Start telnet server

Expand source code

@staticmethod
def start(**kwargs):
        """ Start telnet server """
        config = server.server.ServerConfig()
        config.load_create()
        # If telnet activated
        if config.telnet:
                tools.tasking.Tasks.create_server(TelnetServerInstance(**kwargs))
        else:
                tools.logger.syslog("Telnet disabled in config")

def stop()

Stop telnet server

Expand source code

@staticmethod
def stop():
        """ Stop telnet server """
        # pylint:disable=global-variable-not-assigned
        uos.dupterm(None)
        if Telnet.server[0]:
                Telnet.server[0].close()
                Telnet.server[0] = None
        Telnet.close_client()

class TelnetServerInstance (**kwargs)

Telnet server instance

Constructor

Expand source code

class TelnetServerInstance(tools.tasking.ServerInstance):
        """ Telnet server instance """
        def __init__(self, **kwargs):
                tools.tasking.ServerInstance.__init__(self, **kwargs)

        def start(self):
                """ Start server """
                port = self.kwargs.get("telnet_port",23)
                if tools.support.telnet():
                        # start listening for telnet connections on port 23
                        try:
                                Telnet.stop()
                                Telnet.server[0] = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
                                Telnet.server[0].setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
                                ai = socket.getaddrinfo("0.0.0.0", port)
                                addr = ai[0][4]
                                Telnet.server[0].bind(addr)
                                Telnet.server[0].listen(1)
                                Telnet.server[0].setsockopt(socket.SOL_SOCKET, 20, Telnet.accept)
                        except Exception as err:
                                tools.logger.syslog("Telnet unavailable '%s'"%str(err))
                return "Telnet", port

Ancestors

• tools.tasking.ServerInstance

Methods

def start(self)

Start server

Expand source code

def start(self):
        """ Start server """
        port = self.kwargs.get("telnet_port",23)
        if tools.support.telnet():
                # start listening for telnet connections on port 23
                try:
                        Telnet.stop()
                        Telnet.server[0] = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
                        Telnet.server[0].setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
                        ai = socket.getaddrinfo("0.0.0.0", port)
                        addr = ai[0][4]
                        Telnet.server[0].bind(addr)
                        Telnet.server[0].listen(1)
                        Telnet.server[0].setsockopt(socket.SOL_SOCKET, 20, Telnet.accept)
                except Exception as err:
                        tools.logger.syslog("Telnet unavailable '%s'"%str(err))
        return "Telnet", port