--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_muc_restrict_pm/README.markdown	Tue May 21 00:40:06 2024 -0500
@@ -0,0 +1,30 @@
+---
+labels:
+- 'Stage-Alpha'
+summary: Limit who may send and recieve MUC PMs
+...
+
+# Introduction
+
+This module adds configurable MUC options that restrict and limit who may send MUC PMs to other users.
+
+If a user does not have permissions to send a MUC PM, the MUC will send a policy violation stanza.
+
+# Setup
+
+```lua
+Component "conference.example.org" "muc"
+
+modules_enabled = {
+	"muc_restrict_pm";
+}
+```
+
+Compatibility
+=============
+
+  ----- -----
+  0.12 Works
+  0.11 Probably does not work
+  ----- -----
+

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mod_muc_restrict_pm/mod_muc_restrict_pm.lua	Tue May 21 00:40:06 2024 -0500
@@ -0,0 +1,109 @@
+local st = require "util.stanza";
+
+local affils = {
+	none = 0;
+	member = 1;
+	administrator = 2;
+	owner = 3;
+};
+
+local function get_restrict_pm(room)
+	return room._data.restrict_pm or 'none';
+end
+
+local function set_restrict_pm(room, affil)
+	if get_restrict_pm(room) == affil then return false; end
+	room._data.restrict_pm = affil;
+	return true;
+end
+
+local function can_pm_anyone(room)
+	return room._data.restrict_pm_to or false;
+end
+
+local function set_pm_anyone(room, val)
+	if can_pm_anyone(room) == val then return false; end
+	room._data.restrict_pm_to = val;
+	return true;
+end
+
+local function is_visitor_pm_off(room)
+	return room._data.restrict_pm_visitor or false;
+end
+
+local function set_visitor_pm_off(room, val)
+	if is_visitor_pm_off(room) == val then return false; end
+	room._data.restrict_pm_visitor = val;
+	return true;
+end
+
+module:hook("muc-config-form", function(event)
+	local affilpm = get_restrict_pm(event.room);
+	table.insert(event.form, {
+		name = 'muc#restrict_pm';
+		type = 'list-single';
+		label = 'Allow PMs from';
+		options = {
+			{ value = 'owner', label = 'Owner', default = affilpm == 'owner' },
+			{ value = 'administrator', label = 'Administrators', default = affilpm == 'administrator' },
+			{ value = 'member', label = 'Members', default = affilpm == 'member' },
+			{ value = 'none', label = 'Everyone', default = affilpm == 'none' }
+		}
+	});
+	
+	table.insert(event.form, {
+		name = 'muc#restrict_pm_to';
+		type = 'boolean';
+		label = 'Allow PMs to everyone';
+		value = can_pm_anyone(event.room);
+	});
+	
+	table.insert(event.form, {
+		name = 'muc#restrict_pm_visitor';
+		type = 'boolean';
+		label = 'Disable PMs from Visitors';
+		value = is_visitor_pm_off(event.room);
+	});
+end);
+
+module:hook("muc-config-submitted/muc#restrict_pm", function(event)
+	if set_restrict_pm(event.room, event.value) then
+		event.status_codes["104"] = true;
+	end
+end);
+
+module:hook("muc-config-submitted/muc#restrict_pm_to", function(event)
+	if set_pm_anyone(event.room, event.value) then
+		event.status_codes["104"] = true;
+	end
+end);
+
+module:hook("muc-config-submitted/muc#restrict_pm_visitor", function(event)
+	if set_visitor_pm_off(event.room, event.value) then
+		event.status_codes["104"] = true;
+	end
+end);
+
+local function can_user_pm(room, jid)
+	local affil, pmval = affils[room:get_affiliation(jid) or 'none'], affils[get_restrict_pm(room)];
+	if affil >= pmval then return true; end
+	return false;
+end
+
+module:hook("muc-private-message", function(event)
+	local from_occupant, to_occupant = event.room:get_occupant_by_nick(event.stanza.attr.from), event.room:get_occupant_by_nick(event.stanza.attr.to);
+	
+	-- To self is always okay
+	if to_occupant.bare_jid == from_occupant.bare_jid then return; end
+	
+	-- To moderation is okay
+	if to_occupant and to_occupant.role == 'moderator' then return; end
+	
+	if not is_visitor_pm_off(event.room) or (from_occupant == nil or from_occupant.role ~= 'visitor') then
+		-- If visitors disabled
+		if can_user_pm(event.room, from_occupant.bare_jid) and (can_pm_anyone(event.room) or can_user_pm(event.room, to_occupant.bare_jid)) then return; end;
+	end
+	
+	event.room:route_to_occupant(from_occupant, st.error_reply(event.stanza, "cancel", "policy-violation", "Private messages are disabled", event.room.jid));
+	return false;
+end, 1);