X-Git-Url: https://git.distorted.org.uk/~mdw/exim-config/blobdiff_plain/185b5456076ca86959643ce2f19c98c0f82f281e..48507a38f1410a43af1df681d593290a5e4bf038:/spam.m4

diff --git a/spam.m4 b/spam.m4
index 705fbee..4253e88 100644
--- a/spam.m4
+++ b/spam.m4
@@ -25,6 +25,45 @@ DIVERT(null)
 ###--------------------------------------------------------------------------
 ### Spam filtering.
 
+## The Exim documentation tells lies.
+##
+## : *${run{*<_command_>* *<_args_>*}{*<_string1_>*}{*<_string2_>*}}*
+## :     The command and its arguments are first expanded separately, [...]
+##
+## They aren't.  The whole command-and-args are expanded together, and then
+## split at unquoted spaces.  This unpleasant hack sorts out the mess.
+m4_define(<:SHQUOTE:>, <:"${rxquote:$1}":>)
+
+## Utilities for collecting spam limits.
+m4_define(<:SPAMLIMIT_CHECK:>,
+	<:${if match{$1}{\N^-?[0-9]+$\N} {spam_limit=$1} {}}:>)
+
+m4_define(<:SPAMLIMIT_ROUTER:>,
+<:$1:
+	driver = redirect
+	data = :unknown:
+	verify_only = true
+	condition = ${if !eq{$acl_c_mode}{submission}}
+	condition = ${extract{spam_limit}{$address_data}{false}{true}}:>)
+
+m4_define(<:SPAMLIMIT_SET:>,
+	<:address_data = \
+		${if def:address_data {$address_data}{}} \
+		$1:>)
+
+m4_define(<:SPAMLIMIT_LOOKUP:>,
+	<:condition = ${if exists{$1}}
+	SPAMLIMIT_SET(<:${lookup {$2$3$4@$5/$6} nwildlsearch {$1} \
+			       {SPAMLIMIT_CHECK($value)}}:>):>)
+
+m4_define(<:SPAMLIMIT_USERV:>,
+	<:SPAMLIMIT_SET(<:${run {/usr/bin/timeout 5s \
+					userv CONF_userv_opts \
+					SHQUOTE($1) exim-spam-limit \
+					SHQUOTE($6) SHQUOTE($2) SHQUOTE($3) \
+					SHQUOTE($4) SHQUOTE(@$5)} \
+				{SPAMLIMIT_CHECK($value)}}:>):>)
+
 SECTION(global, policy)m4_dnl
 spamd_address = CONF_spamd_address CONF_spamd_port
 
@@ -34,48 +73,55 @@ SECTION(routers, allspam)m4_dnl
 ## limit and insert it into the `address_data' where the RCPT ACL can find
 ## it.  This router always declines, so it doesn't affect the overall outcome
 ## of the verification.
-fetch_spam_limit:
-	driver = redirect
-	data = :unknown:
-	verify_only = true
+SPAMLIMIT_ROUTER(fetch_spam_limit_lookup)
+	check_local_user
 	local_part_suffix = CONF_user_suffix_list
 	local_part_suffix_optional = true
+	SPAMLIMIT_LOOKUP(CONF_userconf_dir/spam-limit,
+		$local_part_prefix, $local_part, $local_part_suffix, $domain,
+		$sender_address)
+
+SPAMLIMIT_ROUTER(fetch_spam_limit_userv)
 	check_local_user
-	address_data = \
-		${if def:address_data {$address_data}{}} \
-		${if exists {CONF_userconf_dir/spam-limit} \
-		     {${lookup {$local_part_prefix\
-					$local_part\
-					$local_part_suffix\
-					@$domain/\
-					$sender_address} \
-			       nwildlsearch {CONF_userconf_dir/spam-limit} \
-			       {spam_limit=$value} \
-			       {}}} \
-		     {}} \
-		${if exists {CONF_userconf_dir/spam-limit.userv} \
-		     {${run {timeout 5s -- \
-				userv $local_part exim-spam-limit \
-					$sender_address \
-					$local_part_prefix \
-					$local_part \
-					$local_part_suffix \
-					@$domain} \
-			    {${if match{$value}{\N^[0-9]+$\N} \
-				  {spam_limit=$value} \
-				  {}}} \
-			    {}}} \
-		     {}}
+	local_part_suffix = CONF_user_suffix_list
+	local_part_suffix_optional = true
+	condition = ${if exists{CONF_userconf_dir/spam-limit.userv}}
+	SPAMLIMIT_USERV(SHQUOTE($local_part),
+		$local_part_prefix, $local_part, $local_part_suffix, $domain,
+		$sender_address)
 
 SECTION(acl, rcpt-hooks)m4_dnl
 	## Do per-recipient spam-filter processing.
 	require	 acl = rcpt_spam
 
 SECTION(acl, misc)m4_dnl
-rcpt_spam:
+skip_spam_check:
 
-	## If the client is trusted, don't bother with any of this.
+	## If the client is trusted, or this is a new submission, don't
+	## bother with any of this.  We will have verified the sender
+	## fairly aggressively before granting this level of trust.
 	accept	 hosts = +trusted
+	accept	 condition = ${if eq{$acl_c_mode}{submission}}
+
+	## If this is a virtual domain, and it says `spam-check=no', then
+	## skip.
+	accept	 domains = ${if exists{CONF_sysconf_dir/domains.conf} \
+			 {partial0-lsearch; CONF_sysconf_dir/domains.conf} \
+			 {}}
+		!condition = DOMKV(spam-check, {${expand:$value}}{true})
+
+	## Otherwise we should check.
+	deny
+
+rcpt_spam:
+
+	## See if we should do this check.
+	accept	 acl = skip_spam_check
+
+	## Always accept mail to `postmaster'.  Currently this is not
+	## negotiable; maybe a tweak can be added to `domains.conf' if
+	## necessary.
+	accept	 local_parts = postmaster
 
 	## Collect the user's spam threshold from the `address_data'
 	## variable, where it was left by the `fetch_spam_limit' router
@@ -113,8 +159,11 @@ SECTION(acl, data-spam)m4_dnl
 SECTION(acl, misc)m4_dnl
 data_spam:
 
-	## If the client is trusted, don't bother with any of this.
-	accept	 hosts = +trusted
+	## See if we should do this check.
+	accept	 acl = skip_spam_check
+
+	## Check header validity.
+	require	 verify = header_syntax
 
 	## Check the message for spam, comparing to the configured limit.
 	deny	 spam = exim:true
@@ -125,6 +174,7 @@ data_spam:
 	## Insert headers from the spam check now that we've decided to
 	## accept the message.
 	warn
+
 		 ## Convert the limit (currently 10x fixed point) into a
 		 ## decimal for presentation.
 		 set acl_m_spam_limit_presentation = \
@@ -155,7 +205,7 @@ data_spam:
 		 ## their scores.  Leave `<<...>>' around everything else.
 		 set acl_m_spam_tests = \
 			${sg{$acl_m_spam_tests} \
-			    {\N(?s)\n\s*([\d.]+)\s+([-\w]+)\s\N} \
+			    {\N(?s)\n\s*(-?[\d.]+)\s+([-\w]+)\s\N} \
 			    {>>\$2:\$1,<<}}
 
 		 ## Strip everything still in `<<...>>' pairs, including any
@@ -178,7 +228,6 @@ data_spam:
 			limit=$acl_m_spam_limit_presentation, \n\t\
 			tests=$acl_m_spam_tests
 
-
 	## We're good.
 	accept