Reject messages from unjoined resources, with an error

fix #3346

CHANGELOG.rst

@@ -2,6 +2,9 @@ Version 9.0
 ===========
 
 - SIGHUP is now caught and reloads the configuration like SIGUSR1 and 2.
+- Messages from unjoined resources are now rejected instead of being accepted.
+  This helps clients understand that they are not in the room (because of
+  some connection issue for example).
 
 Version 8.3 - 2018-06-01
 ========================

src/bridge/bridge.hpp

@@ -316,7 +316,9 @@ private:
    */
   void add_resource_to_chan(const ChannelKey& channel, const std::string& resource);
   void remove_resource_from_chan(const ChannelKey& channel, const std::string& resource);
+public:
   bool is_resource_in_chan(const ChannelKey& channel, const std::string& resource) const;
+private:
   void remove_all_resources_from_chan(const ChannelKey& channel);
   std::size_t number_of_resources_in_chan(const ChannelKey& channel) const;
 

src/xmpp/biboumi_component.cpp

@@ -273,9 +273,10 @@ void BiboumiComponent::handle_message(const Stanza& stanza)
 
   std::string error_type("cancel");
   std::string error_name("internal-server-error");
-  utils::ScopeGuard stanza_error([this, &from_str, &to_str, &id, &error_type, &error_name](){
+  std::string error_text{};
+  utils::ScopeGuard stanza_error([this, &from_str, &to_str, &id, &error_type, &error_name, &error_text](){
       this->send_stanza_error("message", from_str, to_str, id,
-                              error_type, error_name, "");
+                              error_type, error_name, error_text);
     });
   const XmlNode* body = stanza.get_child("body", COMPONENT_NS);
 
@@ -284,7 +285,15 @@ void BiboumiComponent::handle_message(const Stanza& stanza)
     {
       if (body && !body->get_inner().empty())
         {
-          bridge->send_channel_message(iid, body->get_inner(), id);
+          if (bridge->is_resource_in_chan(iid.to_tuple(), from.resource))
+            bridge->send_channel_message(iid, body->get_inner(), id);
+          else
+            {
+              error_type = "modify";
+              error_name = "not-acceptable";
+              error_text = "You are not a participant in this room.";
+              return;
+            }
         }
       const XmlNode* subject = stanza.get_child("subject", COMPONENT_NS);
       if (subject)

tests/end_to_end/__main__.py

@@ -1404,6 +1404,32 @@ if __name__ == '__main__':
                      "/message[@from='{lower_nick_two}%{irc_server_one}'][@to='{jid_one}/{resource_one}']"),
                  ]
                  ),
+                Scenario("muc_message_from_unjoined_resource",
+                         [
+                         handshake_sequence(),
+                         partial(send_stanza,
+                                 "<presence from='{jid_one}/{resource_one}' to='#foo%{irc_server_one}/{nick_one}' />"),
+                         connection_sequence("irc.localhost", '{jid_one}/{resource_one}'),
+                         partial(expect_stanza,
+                                 "/message/body[text()='Mode #foo [+nt] by {irc_host_one}']"),
+                         partial(expect_stanza, "/presence"),
+                         partial(expect_stanza, "/message/subject"),
+
+                         # Send a channel message
+                        partial(send_stanza, "<message from='{jid_one}/{resource_one}' to='#foo%{irc_server_one}' type='groupchat'><body>coucou</body></message>"),
+                        # Receive the message
+                        partial(expect_stanza,
+                         ("/message[@from='#foo%{irc_server_one}/{nick_one}'][@to='{jid_one}/{resource_one}'][@type='groupchat']/body[text()='coucou']",
+                          "/message/stable_id:stanza-id[@by='#foo%{irc_server_one}'][@id]"),
+                         ),
+
+                         # Send a message from a resource that is not joined
+                         partial(send_stanza, "<message from='{jid_one}/{resource_two}' to='#foo%{irc_server_one}' type='groupchat'><body>coucou</body></message>"),
+                         partial(expect_stanza, ("/message[@type='error']/error[@type='modify']/stanza:text[text()='You are not a participant in this room.']",
+                                                 "/message/error/stanza:not-acceptable"
+                                                 ))
+
+                         ]),
                 Scenario("encoded_channel_join",
                  [
                      handshake_sequence(),