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

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

1 files changed, 20 insertions, 1 deletions

diff --git a/src/xmpp/biboumi_component.cpp b/src/xmpp/biboumi_component.cpp
index 6c0d0e9..c531bd0 100644
--- a/src/xmpp/biboumi_component.cpp
+++ b/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";