Make legacy sesion bind optional and disabled by default

source/Network/Xmpp/Sasl.hs

@@ -107,7 +107,13 @@ auth :: [SaslHandler]
 auth mechanisms resource con = runErrorT $ do
     ErrorT $ xmppSasl mechanisms con
     jid <- ErrorT $ xmppBind resource con
+    ErrorT $ flip withStream con $ do
+        s <- get
+        case establishSession $ streamConfiguration s of
+            False -> return $ Right Nothing
+            True -> do
                 _ <- lift $ startSession con
+                return $ Right Nothing
     return Nothing
 
 -- Produces a `bind' element, optionally wrapping a resource.

source/Network/Xmpp/Types.hs

@@ -1036,6 +1036,10 @@ data StreamConfiguration =
                         , socketDetails :: Maybe (Socket, SockAddr)
                           -- | DNS resolver configuration
                         , resolvConf :: ResolvConf
+                          -- | Whether or not to perform the legacy
+                          -- session bind as defined in the (outdated)
+                          -- RFC 3921 specification
+                        , establishSession :: Bool
                         }
 
 
@@ -1044,6 +1048,7 @@ instance Default StreamConfiguration where
                               , toJid = Nothing
                               , socketDetails = Nothing
                               , resolvConf = defaultResolvConf
+                              , establishSession = False
                               }
 
 data Hostname = Hostname Text deriving (Eq, Show)