exim: Restructure the spam handling acls.

Previously, exim would have its own spam score threshold and expect
spamassassin to mark any messages as spam (even with negative score), so
spam headers could be added on non-rejected messages. Now, we use three
acl clauses instead of just one, allowing us to accept the judgment of
spamassassin again and add spam headers in a separate clause.

diff --git a/etc/exim4/conf.d/acl/40_exim4-config_check_data b/etc/exim4/conf.d/acl/40_exim4-config_check_data
index a1b7024cec9ce32af61b3b10b2ba4577504e25bf..58a65f3f148caf65d85eab9e918419cc3a9a65e4 100644 (file)
--- a/etc/exim4/conf.d/acl/40_exim4-config_check_data
+++ b/etc/exim4/conf.d/acl/40_exim4-config_check_data
@@ -22,27 +22,21 @@ acl_check_data:
     message = No verifiable sender address in message headers
     !verify = header_sender
 
-  # Mark messages with their spamscore and deny messages with a very high
-  # score.
+  # Don't spamcheck big messages
+  accept
+    condition = ${if >{$message_size}{80k}}
+    add_header = X-Spam-Report: Message too big, not scanned.
+
+  # Deny messages with a large spamscore. The threshold is set by
+  # spamassassin, see required_score in /etc/spamassassin/local.cf
   deny
     message = Message was classified as spam
-    # Only scan messages that are small, since spam is hardly ever big (and
-    # scanning big messages costs lots of resources
-    condition = ${if <{$message_size}{80k}}
     # Check using spamassasin, running as the "spamd" user.
-    # This condition will always succeed, since spam assassin is configured
-    # with a very low (even negative) threshold.
     spam = spamd
-    # Add spam headers (these will be added even when the next condition fails
-    # and the message is not denied).
-    add_header = X-Spam-Score: $spam_score ($spam_bar)
-    add_header = X-Spam-Report: $spam_report
-    # Reject any messages with a spam score of more than 20 ($spam_score_int is
-    # $spam_score * 10). This is fairly high, but we don't like really
-    # rejecting messages.
-    condition = ${if >{$spam_score_int}{200}}
 
-  # accept otherwise
+  # Accept any other messages, but add spam headers.
   accept
+    add_header = X-Spam-Score: $spam_score ($spam_bar)
+    add_header = X-Spam-Report: $spam_report
 
 # vim: set sts=2 expandtab sw=2 ai: