From 3638ca67bdeb181c9ed7b4598933c2655846c280 Mon Sep 17 00:00:00 2001
From: Vsevolod Stakhov <vsevolod@rspamd.com>
Date: Thu, 22 Sep 2022 20:53:30 +0100
Subject: [PATCH] [Fix] External_relay: Restore the originating hostname check

Issue: #4272
---
 src/plugins/lua/external_relay.lua | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/plugins/lua/external_relay.lua b/src/plugins/lua/external_relay.lua
index 841eca32fb..9f65490e95 100644
--- a/src/plugins/lua/external_relay.lua
+++ b/src/plugins/lua/external_relay.lua
@@ -159,6 +159,11 @@ strategies.hostname_map = function(rule)
       return
     end
 
+    if not hostname_map:get_key(from_hn) then
+      lua_util.debugm(N, task, 'sender\'s hostname (%s) is not a relay', from_hn)
+      return
+    end
+
     local rcvd_hdrs = task:get_received_headers()
     -- Try find sending hostname in Received headers
     for _, rcvd in ipairs(rcvd_hdrs) do
-- 
2.47.3