# HG changeset patch
# User Matthew Wild <mwild1@gmail.com>
# Date 1661669510 -3600
# Node ID 5f182bccf33f378186f9d3a184fe92f25e51c6e7
# Parent  4d75663d15528e0370597a92b558c6c7573a73d0
mod_component: Require 'from' attribute on stanzas by default

The old behaviour of falling back to the component domain when it is missing
has been merged into the logic for the existing "validate_from_addresses"
option (which is strict by default).

ejabberd already rejects component stanzas with no 'from' (as the XEP
requires), and this has led to compatibility issues for components that were
seemingly working fine with Prosody.

diff -r 4d75663d1552 -r 5f182bccf33f plugins/mod_component.lua
--- a/plugins/mod_component.lua	Sat Aug 27 17:19:13 2022 +0200
+++ b/plugins/mod_component.lua	Sun Aug 28 07:51:50 2022 +0100
@@ -17,7 +17,7 @@
 local sha1 = require "util.hashes".sha1;
 local st = require "util.stanza";
 
-local jid_split = require "util.jid".split;
+local jid_host = require "util.jid".host;
 local new_xmpp_stream = require "util.xmppstream".new;
 local uuid_gen = require "util.uuid".generate;
 
@@ -222,22 +222,19 @@
 	end
 	if not stanza.attr.xmlns or stanza.attr.xmlns == "jabber:client" then
 		local from = stanza.attr.from;
-		if from then
-			if session.component_validate_from then
-				local _, domain = jid_split(stanza.attr.from);
-				if domain ~= session.host then
-					-- Return error
-					session.log("warn", "Component sent stanza with missing or invalid 'from' address");
-					session:close{
-						condition = "invalid-from";
-						text = "Component tried to send from address <"..tostring(from)
-							   .."> which is not in domain <"..tostring(session.host)..">";
-					};
-					return;
-				end
+		if session.component_validate_from then
+			if not from or (jid_host(from) ~= session.host) then
+				-- Return error
+				session.log("warn", "Component sent stanza with missing or invalid 'from' address");
+				session:close{
+					condition = "invalid-from";
+					text = "Component tried to send from address <"..(from or "< [missing 'from' attribute] >")
+						   .."> which is not in domain <"..tostring(session.host)..">";
+				};
+				return;
 			end
-		else
-			stanza.attr.from = session.host; -- COMPAT: Strictly we shouldn't allow this
+		elseif not from then
+			stanza.attr.from = session.host;
 		end
 		if not stanza.attr.to then
 			session.log("warn", "Rejecting stanza with no 'to' address");