Allow vcard requests in MUC, even when IQ requests are disabled

[lovetox]

ejabberd offers a non-standard muc setting muc#roomconfig_allow_query_users

This currently causes vcard requests to fail.

<!-- Outgoing Sa 08 Nov 2025 23:04:47 (movim.eu) -->
<iq to="batiliho@conference.movim.eu/lovetox-occ" type="get" id="vc2" xmlns="jabber:client">
  <vCard xmlns="vcard-temp" />
</iq>


<!-- Incoming Sa 08 Nov 2025 23:04:47 (movim.eu) -->
<iq xmlns="jabber:client" xml:lang="en-US" to="lovetox2@movim.eu/gajim.FSU48890" from="batiliho@conference.movim.eu/lovetox-occ" type="error" id="vc2">
  <vCard xmlns="vcard-temp" />
  <error type="cancel">
    <not-allowed xmlns="urn:ietf:params:xml:ns:xmpp-stanzas" />
    <text xml:lang="en" xmlns="urn:ietf:params:xml:ns:xmpp-stanzas">Queries to the conference members are not allowed in this room</text>
</error>
</iq>

If the intention of this query was that no IQ is routed to the full jid of a participant, then ejabberd should allow the vcard query, because the vcard query is only routed to the bare jid of the participant, and the server of the participant will answer this IQ, and not route it to any resource, making it so that still no IQ would reach the participant.

This in turn would allow avatars to work, while still no IQs would be routed to the full jids of participants.

[badlop]

The patch would be fairly simple, something like:

From c5d16b0ca8dcfc053c09eedd3d014e27d413ab1c Mon Sep 17 00:00:00 2001
From: Badlop <badlop@process-one.net>
Date: Wed, 12 Nov 2025 13:55:43 +0100
Subject: [PATCH] mod_muc: Allow vcard queries even when IQ queries are
 disabled (4489)

---
 src/mod_muc_room.erl | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/src/mod_muc_room.erl b/src/mod_muc_room.erl
index b50b94c1b..5e5c33df5 100644
--- a/src/mod_muc_room.erl
+++ b/src/mod_muc_room.erl
@@ -672,8 +672,11 @@ normal_state({route, ToNick,
 normal_state({route, ToNick,
 	      #iq{from = From, lang = Lang} = Packet},
 	     #state{config = #config{allow_query_users = AllowQuery}} = StateData) ->
+    DirectIqType = direct_iq_type(Packet),
     try maps:get(jid:tolower(From), StateData#state.users) of
-	#user{nick = FromNick} when AllowQuery orelse ToNick == FromNick ->
+	#user{nick = FromNick} when AllowQuery
+                                    orelse DirectIqType == vcard
+                                    orelse ToNick == FromNick ->
 	    case find_jid_by_nick(ToNick, StateData) of
 		false ->
 		    ErrText = ?T("Recipient is not in the conference room"),
@@ -681,7 +684,7 @@ normal_state({route, ToNick,
 		    ejabberd_router:route_error(Packet, Err);
 		To ->
 		    FromJID = jid:replace_resource(StateData#state.jid, FromNick),
-		    case direct_iq_type(Packet) of
+		    case DirectIqType of
 			vcard ->
 			    ejabberd_router:route_iq(
 			      xmpp:set_from_to(Packet, FromJID, jid:remove_resource(To)),
-- 
2.50.1