Added SSL (Secure Sockets Layer) support, inspired by patch by rcaskey (issue 79). The automatic certificate creation does not work well; so the system instead instructs and gives example on how to create your own using third-party tools. I can connect to the server using a twisted-client instance, but not that many regular mud clients seem to support SSL at all (and if they do I don't know to configure them ...)

src/server/server.py

@@ -1,11 +1,11 @@
 """
 This module implements the main Evennia server process, the core of
-the game engine. Don't import this module! If you need to access the 
-server processes from code, instead import sessionhandler.SESSIONS
-and use its 'server' property. 
+the game engine. Don't import this module directly! If you need to
+access the server processes from code, instead go via the session-
+handler: src.sessionhandler.SESSIONS.server
 
 This module should be started with the 'twistd' executable since it
-sets up all the networking features.  (this is done by automatically
+sets up all the networking features.  (this is done automatically
 by game/evennia.py).
 
 """
@@ -39,10 +39,12 @@ SERVERNAME = settings.SERVERNAME
 VERSION = get_evennia_version()
 
 TELNET_PORTS = settings.TELNET_PORTS
+SSL_PORTS = settings.SSL_PORTS
 SSH_PORTS = settings.SSH_PORTS
 WEBSERVER_PORTS = settings.WEBSERVER_PORTS
 
 TELNET_ENABLED = settings.TELNET_ENABLED and TELNET_PORTS
+SSL_ENABLED = settings.SSL_ENABLED and SSL_PORTS
 SSH_ENABLED = settings.SSH_ENABLED and SSH_PORTS
 WEBSERVER_ENABLED = settings.WEBSERVER_ENABLED and WEBSERVER_PORTS
 WEBCLIENT_ENABLED = settings.WEBCLIENT_ENABLED 
@@ -101,7 +103,7 @@ class Evennia(object):
 
         # set a callback if the server is killed abruptly, 
         # by Ctrl-C, reboot etc.
-        reactor.addSystemEventTrigger('before', 'shutdown',self.shutdown, _abrupt=True)
+        reactor.addSystemEventTrigger('before', 'shutdown', self.shutdown, _abrupt=True)
 
         self.game_running = True
                 
@@ -153,6 +155,8 @@ class Evennia(object):
             print "  telnet: " + ", ".join([str(port) for port in TELNET_PORTS])        
         if SSH_ENABLED:
             print "  ssh: " + ", ".join([str(port) for port in SSH_PORTS])
+        if SSL_ENABLED:
+            print "  ssl: " + ", ".join([str(port) for port in SSL_PORTS])
         if WEBSERVER_ENABLED:
             clientstring = ""
             if WEBCLIENT_ENABLED:
@@ -196,32 +200,46 @@ EVENNIA = Evennia(application)
 
 if TELNET_ENABLED:
 
-    # start telnet game connections
+    # Start telnet game connections
 
     from src.server import telnet
 
-    for port in TELNET_PORTS:
+    for port in TELNET_PORTS:        
         factory = protocol.ServerFactory()
         factory.protocol = telnet.TelnetProtocol
         telnet_service = internet.TCPServer(port, factory)
         telnet_service.setName('EvenniaTelnet%s' % port)
         EVENNIA.services.addService(telnet_service)
 
+if SSL_ENABLED:
+
+    # Start SSL game connection (requires PyOpenSSL).
+
+    from src.server import ssl
+    
+    for port in SSL_PORTS: 
+        factory = protocol.ServerFactory()
+        factory.protocol = ssl.SSLProtocol
+        ssl_service = internet.SSLServer(port, factory, ssl.getSSLContext())
+        ssl_service.setName('EvenniaSSL%s' % port)
+        EVENNIA.services.addService(ssl_service)
+
 if SSH_ENABLED:
 
+    # Start SSH game connections. Will create a keypair in evennia/game if necessary.
+    
     from src.server import ssh
 
     for port in SSH_PORTS:
         factory = ssh.makeFactory({'protocolFactory':ssh.SshProtocol,
-                                   'protocolArgs':()})
-        
+                                   'protocolArgs':()})        
         ssh_service = internet.TCPServer(port, factory)
         ssh_service.setName('EvenniaSSH%s' % port)
         EVENNIA.services.addService(ssh_service)
 
 if WEBSERVER_ENABLED:
 
-    # a django-compatible webserver.
+    # Start a django-compatible webserver.
 
     from twisted.python import threadpool
     from src.server.webserver import DjangoWebRoot, WSGIWebServer

src/server/ssl.py

@@ -0,0 +1,69 @@
+"""
+This is a simple context factory for auto-creating 
+SSL keys and certificates. 
+"""
+
+import os, sys
+from twisted.internet import ssl as twisted_ssl
+try:
+    import OpenSSL
+except ImportError:
+    print "  SSL_ENABLED requires PyOpenSSL."
+    sys.exit()
+
+from src.server.telnet import TelnetProtocol
+
+class SSLProtocol(TelnetProtocol):
+    """
+    Communication is the same as telnet, except data transfer
+    is done with encryption. 
+    """
+    pass
+
+def verify_SSL_key_and_cert(keyfile, certfile):
+    """
+    This function looks for RSA key and certificate in the current
+    directory. If files ssl.key and ssl.cert does not exist, they 
+    are created.
+    """
+
+    if not (os.path.exists(keyfile) and os.path.exists(certfile)):
+        # key/cert does not exist. Create. 
+        import subprocess
+        from Crypto.PublicKey import RSA        
+        from twisted.conch.ssh.keys import Key
+
+        print "  Creating SSL key and certificate (this need only be done once)."
+
+        # create the RSA key and store it.
+        KEY_LENGTH = 1024
+        rsaKey = Key(RSA.generate(KEY_LENGTH))
+        keyString = rsaKey.toString(type="OPENSSH")    
+        file(keyfile, 'w+b').write(keyString)
+
+        # try to create the certificate
+        CERT_EXPIRE = 365 * 20 # twenty years validity        
+        # default: 
+        #openssl req -new -x509 -key ssl.key -out ssl.cert -days 7300
+        exestring = "openssl req -new -x509 -key %s -out %s -days %s" % (keyfile, certfile, CERT_EXPIRE)
+        #print "exestring:", exestring
+        try:
+            err = subprocess.call(exestring)#, stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.STDOUT)
+        except OSError, e:
+            print "  %s\n" % e
+            print "  Evennia's SSL context factory could not automatically create an SSL certificate game/%s." % certfile
+            print "  A private key 'ssl.key' was already created. Please create %s manually using the commands valid " % certfile
+            print "  for your operating system." 
+            print "  Example (linux, using the openssl program): "
+            print "    %s" % exestring
+            sys.exit()
+
+def getSSLContext():
+    """
+    Returns an SSL context (key and certificate). This function
+    verifies that key/cert exists before obtaining the context, and if
+    not, creates them.
+    """
+    keyfile, certfile = "ssl.key", "ssl.cert"
+    verify_SSL_key_and_cert(keyfile, certfile)
+    return twisted_ssl.DefaultOpenSSLContextFactory(keyfile, certfile)

src/settings_default.py

@@ -36,10 +36,14 @@ WEBSERVER_PORTS = [8000]
 # Start the evennia ajax client on /webclient
 # (the webserver must also be running)
 WEBCLIENT_ENABLED = True
-# Activate SSH protocol
+# Activate SSH protocol (SecureShell)
 SSH_ENABLED = False
-# Ports to use for SSH
+# Ports to use for SSH 
 SSH_PORTS = [8022]
+# Actiave SSL protocol (SecureSocketLibrary)
+SSL_ENABLED = False
+# Ports to use for SSL 
+SSL_PORTS = [4001]
 # Activate full persistence if you want everything in-game to be
 # stored to the database. With it set, you can do typeclass.attr=value
 # and value will be saved to the database under the name 'attr'.