minimal updates to exim 3.3

[exim-website.git] / system_filter.exim

diff --git a/system_filter.exim b/system_filter.exim
index 585316fe78a8dbc8b5de0c4238bc39bbce131f7b..f920ac8ca5a5143a1fd71cc9b43430124296ab1c 100644 (file)
--- a/system_filter.exim
+++ b/system_filter.exim
@@ -1,6 +1,6 @@
 # Exim filter
-## Version: 0.12
-#      $Id: system_filter.exim,v 1.4 2001/03/20 21:24:40 nigel Exp $
+## Version: 0.13
+#      $Id: system_filter.exim,v 1.3 2001/05/18 10:28:13 nigel Exp $
 
 ## If you haven't worked with exim filters before, read
 ## the install notes at the end of this file.
@@ -53,11 +53,22 @@ then
 endif
 
 # Look for single part MIME messages with suspicious name extensions
-# Check Content-Type header [vb2_regexp]
-if $header_content-type: matches "(?:file)?name=(\"[^\"]+\\\\.(?:vb[se]|ws[fh]|jse?|exe|com|cmd|shs|hta|bat|scr|pif)\"|[\\\\w.-]+\\\\.(?:vb[se]|ws[fh]|jse?|exe|com|cmd|shs|hta|bat|scr|pif))"
+# Check Content-Type header using quoted filename [content_type_quoted_fn_match]
+if $header_content-type: matches "(?:file)?name=(\"[^\"]+\\\\.(?:vb[se]|ws[fh]|jse?|exe|com|cmd|shs|hta|bat|scr|pif)\")"
 then
   fail text "This message has been rejected because it has\n\
-            \ta potentially executable attachment $1\n\
+            \tpotentially executable content $1\n\
+            \tThis form of attachment has been used by\n\
+             \trecent viruses or other malware.\n\
+            \tIf you meant to send this file then please\n\
+            \tpackage it up as a zip file and resend it."
+  seen finish
+endif
+# same again using unquoted filename [content_type_unquoted_fn_match]
+if $header_content-type: matches "(?:file)?name=([\\\\w.-]+\\\\.(?:vb[se]|ws[fh]|jse?|exe|com|cmd|shs|hta|bat|scr|pif))"
+then
+  fail text "This message has been rejected because it has\n\
+            \tpotentially executable content $1\n\
             \tThis form of attachment has been used by\n\
              \trecent viruses or other malware.\n\
             \tIf you meant to send this file then please\n\
@@ -65,11 +76,23 @@ then
   seen finish
 endif
 
+
 # Attempt to catch embedded VBS attachments
 # in emails.   These were used as the basis for 
 # the ILOVEYOU virus and its variants
-# [vb_regexp]
-if $message_body matches "(?:Content-(?:Type:(?>\\\\s*)[\\\\w-]+/[\\\\w-]+|Disposition:(?>\\\\s*)attachment);(?>\\\\s*)(?:file)?name=|begin(?>\\\\s+)[0-7]{3,4}(?>\\\\s+))(\"[^\"]+\\\\.(?:vb[se]|ws[fh]|jse?|exe|com|cmd|shs|hta|bat|scr|pif)\"|[\\\\w.-]+\\\\.(?:vb[se]|ws[fh]|jse?|exe|com|cmd|shs|hta|bat|scr|pif))[\\\\s;]"
+# Quoted filename - [body_quoted_fn_match]
+if $message_body matches "(?:Content-(?:Type:(?>\\\\s*)[\\\\w-]+/[\\\\w-]+|Disposition:(?>\\\\s*)attachment);(?>\\\\s*)(?:file)?name=|begin(?>\\\\s+)[0-7]{3,4}(?>\\\\s+))(\"[^\"]+\\\\.(?:vb[se]|ws[fh]|jse?|exe|com|cmd|shs|hta|bat|scr|pif)\")[\\\\s;]"
+then
+  fail text "This message has been rejected because it has\n\
+            \ta potentially executable attachment $1\n\
+            \tThis form of attachment has been used by\n\
+             \trecent viruses or other malware.\n\
+            \tIf you meant to send this file then please\n\
+            \tpackage it up as a zip file and resend it."
+  seen finish
+endif
+# same again using unquoted filename [body_unquoted_fn_match]
+if $message_body matches "(?:Content-(?:Type:(?>\\\\s*)[\\\\w-]+/[\\\\w-]+|Disposition:(?>\\\\s*)attachment);(?>\\\\s*)(?:file)?name=|begin(?>\\\\s+)[0-7]{3,4}(?>\\\\s+))([\\\\w.-]+\\\\.(?:vb[se]|ws[fh]|jse?|exe|com|cmd|shs|hta|bat|scr|pif))[\\\\s;]"
 then
   fail text "This message has been rejected because it has\n\
             \ta potentially executable attachment $1\n\
@@ -109,6 +132,11 @@ endif
 #      ** Missed changing version number at top of file :-(
 # 0.12 10 May, 2001
 #      Added HTA extension
+# 0.13 22 May, 2001
+#      Reformatted regexps and code to build them so that they are
+#      shorter than the limits on pre exim 3.20 filters.  This will
+#      make them significantly less efficient, but I am getting so
+#      many queries about this that requiring 3.2x appears unsupportable.
 #
 #### Install Notes
 #