Based on the syslog4j library bundled with Graylog.
This plugin allows you to forward messages from a Graylog 2.X server in syslog format. Messages can be dispatched over TCP or UDP and formatted as plain text (classic), structured syslog (rfc 5424) or CEF (experimental).
This plugin supports Graylog 2.4.x, 2.5.x, 3.0.0. Other releases might work, pls try to use latest plugin.
Graylog marketplace
This plugin is also published on graylog marketplace.
https://marketplace.graylog.org/addons/8eb67dc0-b855-455c-a37f-0fa8ae522854
How to build
This project is using Maven and requires Java 8 or higher.
You can build a plugin (JAR) with mvn package
.
How to use
- Download graylog2-output-syslog-.jar from releases and put inside plugins folder
- Restart Graylog server
- Create a new output globally or attached to a stream.
Configuration
- Message dispatch protocol: Select tcp or udp
- Syslog host: Hostname of the remote syslog serevr
- Syslog port: Syslog receiver port on remote host, usually 514
- Format: Specify one of plain, structured, full, cef or custom:FQCN (see below for explanation on values)
Supported formats
plain
Standard plain syslog format. Minimal information. Example:
<14>Mar 31 19:19:02 nginx runit-service - GET /test1/x HTTP/1.1
structured
Based on rfc5424. Sends all fields + log message. Example:
<14>1 2016-03-31T19:31:46.358Z graylog unknown - nginx [all@0 request_verb="GET" remote_addr="192.168.1.37" response_status="404" from_nginx="true" level="6" connection_requests="1" http_version="1.1" response_bytes="1906" source="nginx" message="GET /test1/2 HTTP/1.1" gl2_source_input="566c96abe4b094dfbc2661a8" version="1.1" nginx_access="true" http_user_agent="Wget/1.15 (linux-gnu)" remote_user="-" connection_id="1755" http_referer="-" request_path="/test1/2" gl2_source_node="bebd092c-85d7-49a3-8188-f7af734747fb" _id="34cb0f40-f777-11e5-b30c-0800276c97db" millis="0.002" facility="runit-service" timestamp="2016-03-31T19:31:46.000Z"] GET /test1/2 HTTP/1.1
cef
Common event format aka HP ArcSight format. For this format to work you must set ARCSight port which expects CEF messages without syslog header. Also read CEF format handling below.
full
A variation of structured format except full message is added. Example:
<14>1 2016-03-31T19:19:02.524Z graylog unknown - nginx [all@0 request_verb="GET" remote_addr="192.168.1.37" response_status="404" from_nginx="true" level="6" connection_requests="1" http_version="1.1" response_bytes="1906" source="nginx" message="GET /test1/x HTTP/1.1" gl2_source_input="566c96abe4b094dfbc2661a8" version="1.1" nginx_access="true" http_user_agent="Wget/1.15 (linux-gnu)" remote_user="-" connection_id="970" http_referer="-" request_path="/test1/x" gl2_source_node="bebd092c-85d7-49a3-8188-f7af734747fb" _id="6d833da0-f775-11e5-b30c-0800276c97db" millis="0.002" facility="runit-service" timestamp="2016-03-31T19:19:02.000Z"] source: nginx | message: GET /test1/x HTTP/1.1 { request_verb: GET | remote_addr: 192.168.1.37 | response_status: 404 | from_nginx: true | level: 6 | connection_requests: 1 | http_version: 1.1 | response_bytes: 1906 | gl2_source_input: 566c96abe4b094dfbc2661a8 | version: 1.1 | nginx_access: true | http_user_agent: Wget/1.15 (linux-gnu) | remote_user: - | connection_id: 970 | http_referer: - | request_path: /test1/x | gl2_source_node: bebd092c-85d7-49a3-8188-f7af734747fb | _id: 6d833da0-f775-11e5-b30c-0800276c97db | millis: 0.002 | facility: runit-service | timestamp: 2016-03-31T19:19:02.000Z }
trasparent
A variation of plain sender without facility and source (they are in original message). Example:
<14>Feb 11 17:32:06 graylog01 sshd[26524]: Failed password for admin7 from 10.128.230.28 port 58363 ssh2
snare
Re-build a snare log format of windows event in stream. Example:
<14>Feb 11 17:32:26 graylog01 MSWinEventLog 1 Security 65493 Mon Feb 11 17:32:26 2019 4726 Microsoft-Windows-Security-Auditing N/A N/A AUDIT_SUCCESS WIN-8F8OSAB5AMC.testwin.lan User Account Management A user account was deleted. Subject: Security ID: S-1-5-21-2081084977-3747244460-254679223-500 Account Name: Administrator Account Domain: TESTWIN Logon ID: 0x5F1B5 Target Account: Security ID: S-1-5-21-2081084977-3747244460-254679223-1126 Account Name: admintest Account Domain: TESTWIN Additional Information: Privileges - 65493
custom:FQCN
Specify your implementation of com.wizecore.graylog2.plugin.MessageSender interface.
CEF format handling
Here is the algorithm for CEF message delivery used in this plugin. If you don`t understand that this, consult Common Event Format Guide
Header
Plugin outputs CEF Header with following fields: CEF:0|Graylog|graylog-output-syslog:cefsender|2.3.1|
Device Event Class ID field
Currently it is hardcoded as log:1
Name field
- If message contains
act
field then it is used - If message contains
short_message
field then it is used - else Graylog messageId is used for Name field
New lines are stripped from this field. Proper escaping applied.
Severity field
Mapping performed between syslog level and CEF log level.
Syslog | CEF |
---|---|
DEBUG | 1 |
NOTICE | 2 |
INFO | 3 |
WARN | 6 |
ERROR | 7 |
CRITICAL | 8 |
ALERT | 9 |
EMERGENCY | 10 |
Extension fields
Every existing message fields is written to Extension except message
, full_message
and short_message
Automatically generated extension fields
If existing fields does not contain such keys, following fields will be added to extension:
CEF Key Name | Source |
---|---|
start | Message timestamp, unix time in milliseconds |
msg | Message text (message ) |
externalId | Message ID (assigned by Graylog) |
Links
- https://tools.ietf.org/html/rfc5424
- https://github.com/Graylog2
- http://blog.rootshell.be/2011/05/11/ossec-speaks-arcsight/
- https://groups.google.com/forum/#!topic/ossec-list/3guXmHJYHtY
- http://habrahabr.ru/post/151631/
- http://www.syslog4j.org/
- https://www.graylog.org/resources/gelf-2/
- http://docs.graylog.org/en/1.0/pages/plugins.html
- https://community.saas.hpe.com/t5/ArcSight-Connectors/ArcSight-Common-Event-Format-CEF-Guide/ta-p/1589306