1 #!/usr/bin/env python

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

     3 

     4 # This file is part of Beremiz, a Integrated Development Environment for

     5 # programming IEC 61131-3 automates supporting plcopen standard and CanFestival.

     6 #

     7 # Copyright (C) 2019: Edouard TISSERANT

     8 #

     9 # See COPYING file for copyrights details.

    10 #

    11 # This program is free software; you can redistribute it and/or

    12 # modify it under the terms of the GNU General Public License

    13 # as published by the Free Software Foundation; either version 2

    14 # of the License, or (at your option) any later version.

    15 #

    16 # This program is distributed in the hope that it will be useful,

    17 # but WITHOUT ANY WARRANTY; without even the implied warranty of

    18 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    19 # GNU General Public License for more details.

    20 #

    21 # You should have received a copy of the GNU General Public License

    22 # along with this program; if not, write to the Free Software

    23 # Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

    24 

    25 

    26 """

    27 The TLS-PSK adapter that handles SSL connections instead of regular sockets,

    28 but using Pre Shared Keys instead of Certificates

    29 """

    30 

    31 

    32 

    33 

    34 import socket

    35 import re

    36 import ssl

    37 import Pyro

    38 from Pyro.core import PyroURI

    39 from Pyro.protocol import _connect_socket, TCPConnection, PYROAdapter

    40 from Pyro.errors import ConnectionDeniedError, ProtocolError

    41 from Pyro.util import Log

    42 

    43 try:

    44     import sslpsk

    45 except ImportError as e:

    46     print(str(e))

    47     sslpsk = None

    48 

    49 

    50 class PYROPSKAdapter(PYROAdapter):

    51     """

    52     This is essentialy the same as in Pyro/protocol.py

    53     only raw_sock wrapping into sock through sslpsk.wrap_socket was added

    54     Pyro unfortunately doesn't allow cleaner customization

    55     """

    56 

    57     def bindToURI(self, URI):

    58         with self.lock:   # only 1 thread at a time can bind the URI

    59             try:

    60                 self.URI = URI

    61 

    62                 # This are the statements that differ from Pyro/protocol.py

    63                 raw_sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)

    64                 _connect_socket(raw_sock, URI.address, URI.port, self.timeout)

    65                 sock = sslpsk.wrap_socket(

    66                     raw_sock, psk=Pyro.config.PYROPSK, server_side=False,

    67                     ciphers="PSK-AES256-CBC-SHA",  # available in openssl 1.0.2

    68                     ssl_version=ssl.PROTOCOL_TLSv1)

    69                 # all the rest is the same as in Pyro/protocol.py

    70 

    71                 conn = TCPConnection(sock, sock.getpeername())

    72                 # receive the authentication challenge string, and use that to build the actual identification string.

    73                 try:

    74                     authChallenge = self.recvAuthChallenge(conn)

    75                 except ProtocolError as x:

    76                     # check if we were denied

    77                     if hasattr(x, "partialMsg") and x.partialMsg[:len(self.denyMSG)] == self.denyMSG:

    78                         raise ConnectionDeniedError(Pyro.constants.deniedReasons[int(x.partialMsg[-1])])

    79                     else:

    80                         raise

    81                 # reply with our ident token, generated from the ident passphrase and the challenge

    82                 msg = self._sendConnect(sock, self.newConnValidator.createAuthToken(self.ident, authChallenge, conn.addr, self.URI, None))

    83                 if msg == self.acceptMSG:

    84                     self.conn = conn

    85                     self.conn.connected = 1

    86                     Log.msg('PYROAdapter', 'connected to', str(URI))

    87                     if URI.protocol == 'PYROLOCPSK':

    88                         self.resolvePYROLOC_URI("PYROPSK")  # updates self.URI

    89                 elif msg[:len(self.denyMSG)] == self.denyMSG:

    90                     try:

    91                         raise ConnectionDeniedError(Pyro.constants.deniedReasons[int(msg[-1])])

    92                     except (KeyError, ValueError):

    93                         raise ConnectionDeniedError('invalid response')

    94             except socket.error:

    95                 Log.msg('PYROAdapter', 'connection failed to URI', str(URI))

    96                 raise ProtocolError('connection failed')

    97 

    98 

    99 _getProtocolAdapter = Pyro.protocol.getProtocolAdapter

   100 

   101 

   102 def getProtocolAdapter(protocol):

   103     if protocol in ('PYROPSK', 'PYROLOCPSK'):

   104         return PYROPSKAdapter()

   105     return _getProtocolAdapter(protocol)

   106 

   107 

   108 _processStringURI = Pyro.core.processStringURI

   109 

   110 

   111 def processStringURI(URI):

   112     x = re.match(r'(?P<protocol>PYROLOCPSK)://(?P<hostname>[^\s:]+):?(?P<port>\d+)?/(?P<name>\S*)', URI)

   113     if x:

   114         protocol = x.group('protocol')

   115         hostname = x.group('hostname')

   116         port = x.group('port')

   117         if port:

   118             port = int(port)

   119         else:

   120             port = 0

   121         name = x.group('name')

   122         return PyroURI(hostname, name, port, protocol)

   123     return _processStringURI(URI)

   124 

   125 

   126 def setupPSKAdapter():

   127     """

   128     Add PyroAdapter to the list of available in

   129     Pyro adapters and handle new supported protocols

   130 

   131     This function should be called after

   132     reimport of Pyro module to enable PYROS:// again.

   133     """

   134     if sslpsk is not None:

   135         Pyro.protocol.getProtocolAdapter = getProtocolAdapter

   136         Pyro.core.processStringURI = processStringURI

   137     else:

   138         raise Exception("sslpsk python module unavailable")