Question

i want to add ssl-support to an existing TCP-server which is based on the SocketServer.TCPServer class.
So i overrode the default constructor of the TCPServer class and added the ssl.wrap_socket(…)-call:

class MyTCPServer(SocketServer.ThreadingMixIn, SocketServer.TCPServer):
    def __init__(self, server_address, RequestHandlerClass, bind_and_activate=True):
        # See SocketServer.TCPServer.__init__
        # (added ssl-support):
        SocketServer.BaseServer.__init__(self, server_address,
                                                        RequestHandlerClass)
        self.socket = ssl.wrap_socket(
                    socket.socket(self.address_family, self.socket_type),
                    server_side=True,
                    certfile='cert.pem'
                    )

        if bind_and_activate:
            self.server_bind()
            self.server_activate()

When starting the server, no error occurrs.
So i modified my simple test-client to support ssl, too:

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock = ssl.wrap_socket(s)
sock.connect(('192.168.1.1', 54321))

Again no error occurrs, but the connect-call is blocking. When closing the client using Ctrl+C it shows the following:

Traceback (most recent call last):
  File "exampleClient.py", line 10, in <module>
    sock.do_handshake()
  File "/usr/lib/python2.6/ssl.py", line 293, in do_handshake
    self._sslobj.do_handshake()
KeyboardInterrupt

So the do_handshake is blocking when connecting. Does anyone knows how to fix the problem? I simply want to use an encrypted TCP-connection 🙂

Answer 1

Ok, i found a solution. Now i use something similar to
this using the OpenSSL-package:

Inside the MyTCPServer-Constructor:

SocketServer.BaseServer.__init__(self, server_address, RequestHandlerClass)
ctx = SSL.Context(SSL.SSLv23_METHOD)
cert = 'cert.pem'
ctx.use_privatekey_file(cert)
ctx.use_certificate_file(cert)
self.socket = SSL.Connection(ctx, socket.socket(self.address_family,
                                                        self.socket_type))
if bind_and_activate:
    self.server_bind()
    self.server_activate()

And in the setup-method of the StreamRequestHandler:

self.connection = self.request
self.rfile = socket._fileobject(self.request, "rb", self.rbufsize)
self.wfile = socket._fileobject(self.request, "wb", self.wbufsize)

This seems to work fine 🙂