/etc/l7-protocols/protocols/irc.pat is in l7-protocols 20090528-4.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 | # IRC - Internet Relay Chat - RFC 1459
# Pattern attributes: great fast fast
# Protocol groups: chat ietf_proposed_standard
# Wiki: http://www.protocolinfo.org/wiki/IRC
# Copyright (C) 2008 Matthew Strait, Ethan Sommer; See ../LICENSE
#
# Usually runs on port 6666 or 6667
# Note that chat traffic runs on these ports, but IRC-DCC traffic (which
# can use much more bandwidth) uses a dynamically assigned port, so you
# must have the IRC connection tracking module in your kernel to classify
# this.
#
# This pattern has been tested and is believed to work well.
irc
# First thing that happens is that the client sends NICK and USER, in
# either order. This allows MIRC color codes (\x02-\x0d instead of
# \x09-\x0d).
^(nick[\x09-\x0d -~]*user[\x09-\x0d -~]*:|user[\x09-\x0d -~]*:[\x02-\x0d -~]*nick[\x09-\x0d -~]*\x0d\x0a)
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