fix: Client: Don’t override modified certification errors

When cert errors where detected the certificate-set signal did overwrite
the certficition errors which were already modified by accept_certificate()

This simplifies the code and removes the certificate-set signal

nbxmpp/client.py

@@ -232,6 +232,8 @@ class Client(Observable):
 
     @property
     def peer_certificate(self):
+        if self._con is not None:
+            return self._con.peer_certificate
         return self._peer_certificate, self._peer_certificate_errors
 
     @property
@@ -360,6 +362,8 @@ class Client(Observable):
             return
 
         self.state = StreamState.CONNECTING
+        self._peer_certificate = None
+        self._peer_certificate_errors = None
         self._reset_error()
 
         self._con = self._get_connection(self._log_context,
@@ -375,7 +379,6 @@ class Client(Observable):
         self._con.subscribe('data-sent', self._on_data_sent)
         self._con.subscribe('data-received', self._on_data_received)
         self._con.subscribe('bad-certificate', self._on_bad_certificate)
-        self._con.subscribe('certificate-set', self._on_certificate_set)
         self._con.connect()
 
     def _get_connection(self, *args):
@@ -537,12 +540,9 @@ class Client(Observable):
             connection.peer_certificate
         self._set_error(StreamError.BAD_CERTIFICATE, 'bad certificate')
 
-    def _on_certificate_set(self, connection, _signal_name):
-        self._peer_certificate, self._peer_certificate_errors = \
-            connection.peer_certificate
-
     def accept_certificate(self):
         self._log.info('Certificate accepted')
+        assert self._peer_certificate is not None
         self._accepted_certificates.append(self._peer_certificate)
         self._connect()
 

nbxmpp/connection.py

@@ -37,7 +37,6 @@ class Connection(Observable):
         data-sent
         data-received
         bad-certificate
-        certificate-set
         connection-failed
         disconnected
     '''

nbxmpp/tcp.py

@@ -125,11 +125,15 @@ class TCPConnection(Connection):
         return False
 
     def _on_certificate_set(self, connection, _param):
-        self._peer_certificate = connection.props.peer_certificate
-        self._peer_certificate_errors = convert_tls_error_flags(
-            connection.props.peer_certificate_errors)
+        if self._peer_certificate is None:
+            # If the cert has errors _check_certificate() will set the cert and
+            # _accept_certificate() will modify the error set. If this is the
+            # case _accept_certificate() modifies the errors.
+            self._peer_certificate = connection.props.peer_certificate
+            self._peer_certificate_errors = convert_tls_error_flags(
+                connection.props.peer_certificate_errors)
+
         self._tls_handshake_in_progress = False
-        self.notify('certificate-set')
 
     def _on_connect_finished(self, client, result, _user_data):
         try:

nbxmpp/websocket.py

@@ -99,8 +99,6 @@ class WebsocketConnection(Connection):
         self._peer_certificate = certificate
         self._peer_certificate_errors = convert_tls_error_flags(errors)
 
-        self.notify('certificate-set')
-
         if self._accept_certificate():
             return