# FTP - File Transfer Protocol - RFC 959
-# Pattern quality: great fast
+# Pattern attributes: great notsofast fast
+# Protocol groups: document_retrieval ietf_internet_standard
+# Wiki: http://protocolinfo.org/wiki/FTP
+# Copyright (C) 2008 Matthew Strait, Ethan Sommer; See ../LICENSE
#
# Usually runs on port 21. Note that the data stream is on a dynamically
# assigned port, which means that you will need the FTP connection
# tracking module in your kernel to usefully match FTP data transfers.
#
-# This pattern is well tested. If it does not
-# work for you, or you believe it could be improved, please post to
-# l7-filter-developers@lists.sf.net . This list may be subscribed to at
-# http://lists.sourceforge.net/lists/listinfo/l7-filter-developers
+# This pattern is well tested.
#
-# Matches the first two things a server should say. Most servers say
-# something after 220, even though they don't have to, and it usually
-# includes the string "ftp" (l7-filter is case insensitive).
-# This includes proftpd, vsftpd, wuftpd, warftpd, pureftpd, Bulletproof
-# FTP Server, and whatever ftp.microsoft.com uses. Just in case, the next
-# thing the server sends is a 331. All the above servers also send
-# something including "password" after this code.
+# Handles the first two things a server should say:
+#
+# First, the server says it's ready by sending "220". Most servers say
+# something after 220, even though they don't have to, and it usually
+# includes the string "ftp" (l7-filter is case insensitive). This
+# includes proftpd, vsftpd, wuftpd, warftpd, pureftpd, Bulletproof FTP
+# Server, and whatever ftp.microsoft.com uses. Almost all servers use only
+# ASCII printable characters between the "220" and the "FTP", but non-English
+# ones might use others.
+#
+# The next thing the server sends is a 331. All the above servers also
+# send something including "password" after this code. By default, we
+# do not match on this because it takes another packet and is more work
+# for regexec.
+
ftp
-# actually, let's just do the first for now, it's faster
+# by default, we allow only ASCII
^220[\x09-\x0d -~]*ftp
-# This is ~10x faster if the stream starts with "220"
+# This covers UTF-8 as well
+#^220[\x09-\x0d -~\x80-\xfd]*ftp
+
+# This allows any characters and is about 4x faster than either of the above
+# (which are about the same as each other)
#^220.*ftp
-# This will match more, but much slower
+# This is much slower
#^220[\x09-\x0d -~]*ftp|331[\x09-\x0d -~]*password
# This pattern is more precise, but takes longer to match. (3 packets vs. 1)