/etc/l7-protocols/protocols/snmp.pat is in l7-protocols 20090528-4.
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1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 | # SNMP - Simple Network Management Protocol - RFC 1157
# Pattern attributes: good veryfast fast superset
# Protocol groups: networking ietf_internet_standard
# Wiki: http://www.protocolinfo.org/wiki/SNMP
# Copyright (C) 2008 Matthew Strait, Ethan Sommer; See ../LICENSE
#
# Usually runs on UDP ports 161 (monitoring) and 162 (traps).
#
# These filters match SNMPv1 packets without fail, and are made as
# specific as possible not to match any ASN.1 encoded protocols. However
# these could still be matched by other protocols that use ASN.1 encoding
# Contributed by Goli SriSairam <goli_sai AT yahoo.com>
# This pattern has been tested and is believed to work well.
# All SNMPv1 traffic. See snmp-mon.pat and snmp-trap.pat for details.
snmp
^\x02\x01\x04.+([\xa0-\xa3]\x02[\x01-\x04].?.?.?.?\x02\x01.?\x02\x01.?\x30|\xa4\x06.+\x40\x04.?.?.?.?\x02\x01.?\x02\x01.?\x43)
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