Make sure we keep the stable-id and origin-id nodes when required

See https://xmpp.org/extensions/xep-0359.html

src/bridge/bridge.cpp

@@ -196,7 +196,7 @@ bool Bridge::join_irc_channel(const Iid& iid, std::string nickname,
   return false;
 }
 
-void Bridge::send_channel_message(const Iid& iid, const std::string& body, std::string id)
+void Bridge::send_channel_message(const Iid& iid, const std::string& body, std::string id, std::vector<XmlNode> nodes_to_reflect)
 {
   if (iid.get_server().empty())
     {
@@ -234,15 +234,21 @@ void Bridge::send_channel_message(const Iid& iid, const std::string& body, std::
       if (!first || id.empty())
         id = utils::gen_uuid();
 
-      MessageCallback mirror_to_all_resources = [this, iid, uuid, id](const IrcClient* irc, const IrcMessage& message) {
+      MessageCallback mirror_to_all_resources = [this, iid, uuid, id, nodes_to_reflect](const IrcClient* irc, const IrcMessage& message) {
         std::string line = message.arguments[1];
         // “temporary” workaround for \01ACTION…\01 -> /me messages
         if ((line.size() > strlen("\01ACTION\01")) &&
             (line.substr(0, 7) == "\01ACTION") && line[line.size() - 1] == '\01')
           line = "/me " + line.substr(8, line.size() - 9);
         for (const auto& resource: this->resources_in_chan[iid.to_tuple()])
-          this->xmpp.send_muc_message(std::to_string(iid), irc->get_own_nick(), this->make_xmpp_body(line),
-                                      this->user_jid + "/" + resource, uuid, id);
+          {
+            auto stanza = this->xmpp.make_muc_message(std::to_string(iid), irc->get_own_nick(), this->make_xmpp_body(line),
+                                                       this->user_jid + "/"
+                                                       + resource, uuid, id);
+            for (const auto& node: nodes_to_reflect)
+              stanza.add_child(node);
+            this->xmpp.send_stanza(stanza);
+          }
       };
 
       if (line.substr(0, 5) == "/mode")
@@ -859,8 +865,10 @@ void Bridge::send_message(const Iid& iid, const std::string& nick, const std::st
 #endif
       for (const auto& resource: this->resources_in_chan[iid.to_tuple()])
         {
-          this->xmpp.send_muc_message(std::to_string(iid), nick, this->make_xmpp_body(body, encoding),
-                                      this->user_jid + "/" + resource, uuid, utils::gen_uuid());
+          auto stanza = this->xmpp.make_muc_message(std::to_string(iid), nick, this->make_xmpp_body(body, encoding),
+                                                     this->user_jid + "/"
+                                                     + resource, uuid, utils::gen_uuid());
+          this->xmpp.send_stanza(stanza);
         }
     }
   else

src/bridge/bridge.hpp

@@ -81,7 +81,7 @@ public:
                         HistoryLimit history_limit,
                         const bool force_join);
 
-  void send_channel_message(const Iid& iid, const std::string& body, std::string id);
+  void send_channel_message(const Iid& iid, const std::string& body, std::string id, std::vector<XmlNode> nodes_to_reflect);
   void send_private_message(const Iid& iid, const std::string& body, const std::string& type="PRIVMSG");
   void send_raw_message(const std::string& hostname, const std::string& body);
   void leave_irc_channel(Iid&& iid, const std::string& status_message, const std::string& resource);

src/xmpp/biboumi_component.cpp

@@ -286,7 +286,26 @@ void BiboumiComponent::handle_message(const Stanza& stanza)
       if (body && !body->get_inner().empty())
         {
           if (bridge->is_resource_in_chan(iid.to_tuple(), from.resource))
-            bridge->send_channel_message(iid, body->get_inner(), id);
+            {
+              // Extract some XML nodes that we must include in the
+              // reflection (if any), because XMPP says so
+              std::vector<XmlNode> nodes_to_reflect;
+              const XmlNode* origin_id = stanza.get_child("origin-id", STABLE_ID_NS);
+              if (origin_id)
+                nodes_to_reflect.push_back(*origin_id);
+              const auto own_address = std::to_string(iid) + '@' + this->served_hostname;
+              for (const XmlNode* stable_id: stanza.get_children("stable-id", STABLE_ID_NS))
+                {
+                  // Stanza ID generating entities, which encounter a
+                  // <stanza-id/> element where the 'by' attribute matches
+                  // the 'by' attribute they would otherwise set, MUST
+                  // delete that element even if they are not adding their
+                  // own stanza ID.
+                  if (stable_id->get_tag("by") != own_address)
+                    nodes_to_reflect.push_back(*stable_id);
+                }
+              bridge->send_channel_message(iid, body->get_inner(), id, std::move(nodes_to_reflect));
+            }
           else
             {
               error_type = "modify";

src/xmpp/xmpp_component.cpp

@@ -367,7 +367,7 @@ void XmppComponent::send_topic(const std::string& from, Xmpp::body&& topic, cons
   this->send_stanza(message);
 }
 
-void XmppComponent::send_muc_message(const std::string& muc_name, const std::string& nick, Xmpp::body&& xmpp_body, const std::string& jid_to, std::string uuid, std::string id)
+Stanza XmppComponent::make_muc_message(const std::string& muc_name, const std::string& nick, Xmpp::body&& xmpp_body, const std::string& jid_to, std::string uuid, std::string id)
 {
   Stanza message("message");
   message["to"] = jid_to;
@@ -399,7 +399,7 @@ void XmppComponent::send_muc_message(const std::string& muc_name, const std::str
       stanza_id["id"] = std::move(uuid);
     }
 
-  this->send_stanza(message);
+  return message;
 }
 
 #ifdef USE_DATABASE

src/xmpp/xmpp_component.hpp

@@ -135,7 +135,7 @@ public:
   /**
    * Send a (non-private) message to the MUC
    */
-  void send_muc_message(const std::string& muc_name, const std::string& nick, Xmpp::body&& body, const std::string& jid_to,
+  Stanza make_muc_message(const std::string& muc_name, const std::string& nick, Xmpp::body&& xmpp_body, const std::string& jid_to,
                           std::string uuid, std::string id);
 #ifdef USE_DATABASE
   /**

tests/end_to_end/scenarios/stable_id.py

@@ -0,0 +1,26 @@
+from scenarios import *
+
+import scenarios.simple_channel_join
+
+# see https://xmpp.org/extensions/xep-0359.html
+
+scenario = (
+    scenarios.simple_channel_join.scenario,
+
+    send_stanza("""<message id='first_id' from='{jid_one}/{resource_one}' to='#foo%{irc_server_one}' type='groupchat'>
+      <origin-id xmlns='urn:xmpp:sid:0' id='client-origin-id'/>
+      <stanza-id xmlns='urn:xmpp:sid:0' id='client-stanza-id'/>
+      <body>coucou</body></message>"""),
+
+    # Entities, which are routing stanzas, SHOULD NOT strip any elements
+    # qualified by the 'urn:xmpp:sid:0' namespace from message stanzas
+    # unless the preceding rule applied to those elements.
+    expect_stanza("/message/stable_id:origin-id[@id='client-origin-id']",
+    # Stanza ID generating entities, which encounter a <stanza-id/>
+    # element where the 'by' attribute matches the 'by' attribute they
+    # would otherwise set, MUST delete that element even if they are not
+    # adding their own stanza ID.
+                  "/message/stable_id:stanza-id[@id][@by='#foo%{irc_server_one}']",
+                  "!/message/stable_id:stanza-id[@id='client-stanza-id']",
+    ),
+)