reject relaying attempts first?

[Robert Millan]

What would you think of rejecting relaying attempts as soon as we know we're
not dealing with a host that is authorised to relay?  I.e., right after the
MUA authentication checks.

Index: 30_exim4-config_check_rcpt
===================================================================
--- 30_exim4-config_check_rcpt  (revision 1523)
+++ 30_exim4-config_check_rcpt  (working copy)
@@ -148,6 +148,11 @@
     authenticated = *
     control = submission/sender_retain

+  # We are not going to relay for this message, so if it's a relaying attempt,
+  # it can be rejected right now, before the more expensive checks take place.
+  deny
+    !domains = +local_domains : +relay_to_domains
+    message = relay not permitted

   # deny bad senders (envelope sender)
   # CONFDIR/local_sender_blacklist holds a list of envelope senders that

-- 
Robert Millan

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