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@mesimeris
mesimeris / grok-patterns
Last active April 16, 2021 22:10
LOGSTASH: syslog listener filtering with grok patterns and applying useful tags
# NOTE: These patterns take into account the additional log-line information passed to the logstash listener from rsyslog. YMMV.
DHCPD ((%{SYSLOGTIMESTAMP:timestamp})\s*(%{HOSTNAME:hostname})\s*dhcpd\S+\s*(%{WORD:dhcp_action})?.*[for|on] (%{IPV4:dhcp_client_ip})?.*[from|to] (%{COMMONMAC:dhcp_client_mac})?.*via (%{USERNAME:interface}))
IPTABLES ((%{SYSLOGTIMESTAMP:nf_timestamp})\s*(%{HOSTNAME:nf_host})\s*kernel\S+\s*(%{WORD:nf_action})?.*IN=(%{USERNAME:nf_in_interface})?.*OUT=(%{USERNAME:nf_out_interface})?.*MAC=(%{COMMONMAC:nf_dst_mac}):(%{COMMONMAC:nf_src_mac})?.*SRC=(%{IPV4:nf_src_ip}).*DST=(%{IPV4:nf_dst_ip}).*PROTO=(%{WORD:nf_protocol}).?*SPT=(%{INT:nf_src_port}?.*DPT=%{INT:nf_dst_port}?.*))
DNS ((%{MONTHDAY:day})-(%{MONTH:month})-(%{YEAR:year}) (%{TIME:timestamp}) client (%{IPV4:dns_client_ip})#(%{NONNEGINT:dns_uuid})?.*query: (%{HOSTNAME:dns_dest}) (%{WORD:dns_type}) (%{WORD:dns_record})?.*(%{IPV4:dns_server}))
PGSQL ((%{SYSLOGTIMESTAMP:pgsql_timestamp}) (%{HOSTNAME:pgsql_hostname})?.*SAST >(%{WORD:pgs