minor formatting and documentation additions

src/Network/XMPP/TLS.hs

@@ -18,12 +18,11 @@ import           Network.XMPP.Stream
 import           Network.XMPP.Types
 
 starttlsE :: Element
-starttlsE =
+starttlsE = Element "{urn:ietf:params:xml:ns:xmpp-tls}starttls" [] []
-  Element "{urn:ietf:params:xml:ns:xmpp-tls}starttls" [] []
 
 exampleParams :: TLS.TLSParams
 exampleParams = TLS.defaultParams
-                      {pConnectVersion    = TLS.TLS10
+    { pConnectVersion    = TLS.TLS10
     , pAllowedVersions   = [TLS.SSL3, TLS.TLS10, TLS.TLS11]
     , pCiphers           = [TLS.cipher_AES128_SHA1]
     , pCompressions      = [TLS.nullCompression]
@@ -31,7 +30,7 @@ exampleParams = TLS.defaultParams
     , pUseSecureRenegotiation = False -- No renegotiation
     , pCertificates      = [] -- TODO
     , pLogging           = TLS.defaultLogging -- TODO
-                      , onCertificatesRecv = \ _certificate ->
+    , onCertificatesRecv = \_certificate ->
           return TLS.CertificateUsageAccept
     }
 
@@ -40,14 +39,16 @@ data XMPPTLSError = TLSError TLSError
                   | TLSNoServerSupport
                   | TLSNoConnection
                   | TLSStreamError StreamError
+                  | XMPPTLSError -- General instance used for the Error instance
                     deriving (Show, Eq, Typeable)
 
 instance Error XMPPTLSError where
-  noMsg = TLSNoConnection -- TODO: What should we choose here?
+  noMsg = XMPPTLSError
 
+-- Pushes "<starttls/>, waits for "<proceed/>", performs the TLS handshake, and
+-- restarts the stream. May throw errors.
 startTLS :: TLS.TLSParams -> XMPPConMonad (Either XMPPTLSError ())
-startTLS params = Ex.handle (return . Left . TLSError)
+startTLS params = Ex.handle (return . Left . TLSError) . runErrorT $ do
-  . runErrorT $ do
     features <- lift $ gets sFeatures
     handle' <- lift $ gets sConHandle
     handle <- maybe (throwError TLSNoConnection) return handle'
@@ -56,13 +57,13 @@ startTLS params = Ex.handle (return . Left . TLSError)
     answer <- lift $ pullElement
     case answer of
         Element "{urn:ietf:params:xml:ns:xmpp-tls}proceed" [] [] -> return ()
-        Element "{urn:ietf:params:xml:ns:xmpp-tls}failure" _ _
+        Element "{urn:ietf:params:xml:ns:xmpp-tls}failure" _ _ ->
-            -> lift . Ex.throwIO $ StreamConnectionError
+            lift . Ex.throwIO $ StreamConnectionError
             -- TODO: find something more suitable
-        e -> lift . Ex.throwIO . StreamXMLError
+        e -> lift . Ex.throwIO . StreamXMLError $
-               $ "Unexpected element: " ++ ppElement e
+            "Unexpected element: " ++ ppElement e
     (raw, _snk, psh, ctx) <- lift $ TLS.tlsinit params handle
-      lift $ modify (\x -> x
+    lift $ modify ( \x -> x
                   { sRawSrc = raw
 --                , sConSrc =  -- Note: this momentarily leaves us in an
                                -- inconsistent state
@@ -72,4 +73,3 @@ startTLS params = Ex.handle (return . Left . TLSError)
     either (lift . Ex.throwIO) return =<< lift xmppRestartStream
     modify (\s -> s{sConnectionState = XmppConnectionSecured})
     return ()
-