Handle some iq of type='error' as valid ping response

fix #3251

src/xmpp/biboumi_component.cpp

@@ -564,6 +564,12 @@ void BiboumiComponent::handle_iq(const Stanza& stanza)
   else if (type == "error")
     {
       stanza_error.disable();
+      const auto it = this->waiting_iq.find(id);
+      if (it != this->waiting_iq.end())
+        {
+          it->second(bridge, stanza);
+          this->waiting_iq.erase(it);
+        }
     }
   }
   catch (const IRCNotConnected& ex)
@@ -807,8 +813,14 @@ void BiboumiComponent::send_ping_request(const std::string& from,
         {
           log_error("Received a corresponding ping result, but the 'to' from "
                     "the response mismatches the 'from' of the request");
+          return;
         }
-      else
+      const std::string type = stanza.get_tag("type");
+      const XmlNode* error = stanza.get_child("error", COMPONENT_NS);
+      // Check if what we receive is considered a valid response. And yes, those errors are valid responses
+      if (type == "result" ||
+          (type == "error" && error && (error->get_child("feature-not-implemented", STANZA_NS) ||
+                                        error->get_child("service-unavailable", STANZA_NS))))
         bridge->send_irc_ping_result({from, bridge}, id);
     };
   this->waiting_iq[id] = result_cb;

tests/end_to_end/__main__.py

@@ -1101,6 +1101,44 @@ if __name__ == '__main__':
                              ),
                      partial(expect_stanza, "/message[@from='#biboumi\\40louiz.org\\3a80%{irc_server_one}'][@type='groupchat']/subject[not(text())]"),
                  ]),
+                Scenario("self_ping_with_error",
+                 [
+                     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[@to='{jid_one}/{resource_one}'][@from='#foo%{irc_server_one}/{nick_one}']/muc_user:x/muc_user:item[@affiliation='admin'][@role='moderator']",
+                              "/presence/muc_user:x/muc_user:status[@code='110']")
+                             ),
+                     partial(expect_stanza, "/message[@from='#foo%{irc_server_one}'][@type='groupchat']/subject[not(text())]"),
+
+                     # Send a ping to ourself
+                     partial(send_stanza,
+                             "<iq type='get' from='{jid_one}/{resource_one}' id='first_ping' to='#foo%{irc_server_one}/{nick_one}'><ping xmlns='urn:xmpp:ping' /></iq>"),
+                     # We receive our own ping request,
+                     partial(expect_stanza,
+                             "/iq[@from='{lower_nick_one}%{irc_server_one}'][@type='get'][@to='{jid_one}/{resource_one}'][@id='gnip_tsrif']"),
+                     # Respond to the request with an error
+                     partial(send_stanza,
+                             "<iq from='{jid_one}/{resource_one}' id='gnip_tsrif' to='{lower_nick_one}%{irc_server_one}' type='error'><error type='cancel'><feature-not-implemented xmlns='urn:ietf:params:xml:ns:xmpp-stanzas'/></error></iq>"),
+                     partial(expect_stanza,
+                             "/iq[@from='#foo%{irc_server_one}/{nick_one}'][@type='result'][@to='{jid_one}/{resource_one}'][@id='first_ping']"),
+
+                     # Send a ping to ourself
+                     partial(send_stanza,
+                             "<iq type='get' from='{jid_one}/{resource_one}' id='first_ping' to='#foo%{irc_server_one}/{nick_one}'><ping xmlns='urn:xmpp:ping' /></iq>"),
+                     # We receive our own ping request,
+                     partial(expect_stanza,
+                             "/iq[@from='{lower_nick_one}%{irc_server_one}'][@type='get'][@to='{jid_one}/{resource_one}'][@id='gnip_tsrif']"),
+                     # Respond to the request with an error
+                     partial(send_stanza,
+                             "<iq from='{jid_one}/{resource_one}' id='gnip_tsrif' to='{lower_nick_one}%{irc_server_one}' type='error'><error type='cancel'><service-unavailable xmlns='urn:ietf:params:xml:ns:xmpp-stanzas'/></error></iq>"),
+                     partial(expect_stanza,
+                             "/iq[@from='#foo%{irc_server_one}/{nick_one}'][@type='result'][@to='{jid_one}/{resource_one}'][@id='first_ping']"),
+                 ]),
                 Scenario("self_ping_on_real_channel",
                  [
                      handshake_sequence(),