mirror of
https://github.com/zeek/zeek.git
synced 2025-10-07 09:08:20 +00:00
ded98cd373
This is based on commit 2731def9159247e6da8a3191783c89683363689c from the zeek-docs repo.
364 lines
13 KiB
ReStructuredText
364 lines
13 KiB
ReStructuredText
:tocdepth: 3
|
|
|
|
base/frameworks/signatures/main.zeek
|
|
====================================
|
|
.. zeek:namespace:: Signatures
|
|
|
|
Script level signature support. See the
|
|
:doc:`signature documentation </frameworks/signatures>` for more
|
|
information about Zeek's signature engine.
|
|
|
|
:Namespace: Signatures
|
|
:Imports: :doc:`base/frameworks/notice </scripts/base/frameworks/notice/index>`
|
|
|
|
Summary
|
|
~~~~~~~
|
|
Runtime Options
|
|
###############
|
|
================================================================================== ====================================================================
|
|
:zeek:id:`Signatures::ignored_ids`: :zeek:type:`pattern` :zeek:attr:`&redef` Signature IDs that should always be ignored.
|
|
:zeek:id:`Signatures::summary_interval`: :zeek:type:`interval` :zeek:attr:`&redef` The interval between when :zeek:enum:`Signatures::Signature_Summary`
|
|
notices are generated.
|
|
================================================================================== ====================================================================
|
|
|
|
Redefinable Options
|
|
###################
|
|
================================================================================== ====================================================================
|
|
:zeek:id:`Signatures::count_thresholds`: :zeek:type:`set` :zeek:attr:`&redef` Generate a notice if a :zeek:enum:`Signatures::SIG_COUNT_PER_RESP`
|
|
signature is triggered as often as given by one of these thresholds.
|
|
:zeek:id:`Signatures::horiz_scan_thresholds`: :zeek:type:`set` :zeek:attr:`&redef` Generate a notice if, for a pair [orig, signature], the number of
|
|
different responders has reached one of the thresholds.
|
|
:zeek:id:`Signatures::vert_scan_thresholds`: :zeek:type:`set` :zeek:attr:`&redef` Generate a notice if, for a pair [orig, resp], the number of
|
|
different signature matches has reached one of the thresholds.
|
|
================================================================================== ====================================================================
|
|
|
|
State Variables
|
|
###############
|
|
======================================================================================================================== ========================
|
|
:zeek:id:`Signatures::actions`: :zeek:type:`table` :zeek:attr:`&redef` :zeek:attr:`&default` = ``Signatures::SIG_ALARM`` Actions for a signature.
|
|
======================================================================================================================== ========================
|
|
|
|
Types
|
|
#####
|
|
================================================== ======================================================================
|
|
:zeek:type:`Signatures::Action`: :zeek:type:`enum` These are the default actions you can apply to signature matches.
|
|
:zeek:type:`Signatures::Info`: :zeek:type:`record` The record type which contains the column fields of the signature log.
|
|
================================================== ======================================================================
|
|
|
|
Redefinitions
|
|
#############
|
|
============================================ =============================================================
|
|
:zeek:type:`Log::ID`: :zeek:type:`enum` The signature logging stream identifier.
|
|
|
|
* :zeek:enum:`Signatures::LOG`
|
|
:zeek:type:`Notice::Type`: :zeek:type:`enum` Add various signature-related notice types.
|
|
|
|
* :zeek:enum:`Signatures::Count_Signature`:
|
|
The same signature has triggered multiple times for a host.
|
|
|
|
* :zeek:enum:`Signatures::Multiple_Sig_Responders`:
|
|
Host has triggered the same signature on multiple hosts as
|
|
defined by the :zeek:id:`Signatures::horiz_scan_thresholds`
|
|
variable.
|
|
|
|
* :zeek:enum:`Signatures::Multiple_Signatures`:
|
|
Host has triggered many signatures on the same host.
|
|
|
|
* :zeek:enum:`Signatures::Sensitive_Signature`:
|
|
Generic notice type for notice-worthy signature matches.
|
|
|
|
* :zeek:enum:`Signatures::Signature_Summary`:
|
|
Summarize the number of times a host triggered a signature.
|
|
============================================ =============================================================
|
|
|
|
Events
|
|
######
|
|
======================================================== =================================================================
|
|
:zeek:id:`Signatures::log_signature`: :zeek:type:`event` This event can be handled to access/alter data about to be logged
|
|
to the signature logging stream.
|
|
======================================================== =================================================================
|
|
|
|
Hooks
|
|
#####
|
|
=============================================================== =============================================
|
|
:zeek:id:`Signatures::log_policy`: :zeek:type:`Log::PolicyHook` A default logging policy hook for the stream.
|
|
=============================================================== =============================================
|
|
|
|
|
|
Detailed Interface
|
|
~~~~~~~~~~~~~~~~~~
|
|
Runtime Options
|
|
###############
|
|
.. zeek:id:: Signatures::ignored_ids
|
|
:source-code: base/frameworks/signatures/main.zeek 110 110
|
|
|
|
:Type: :zeek:type:`pattern`
|
|
:Attributes: :zeek:attr:`&redef`
|
|
:Default:
|
|
|
|
::
|
|
|
|
/^?(NO_DEFAULT_MATCHES)$?/
|
|
|
|
:Redefinition: from :doc:`/scripts/policy/misc/detect-traceroute/main.zeek`
|
|
|
|
``+=``::
|
|
|
|
/^?(traceroute-detector.*)$?/
|
|
|
|
:Redefinition: from :doc:`/scripts/policy/protocols/http/detect-webapps.zeek`
|
|
|
|
``+=``::
|
|
|
|
/^?(^webapp-)$?/
|
|
|
|
|
|
Signature IDs that should always be ignored.
|
|
|
|
.. zeek:id:: Signatures::summary_interval
|
|
:source-code: base/frameworks/signatures/main.zeek 126 126
|
|
|
|
:Type: :zeek:type:`interval`
|
|
:Attributes: :zeek:attr:`&redef`
|
|
:Default: ``1.0 day``
|
|
|
|
The interval between when :zeek:enum:`Signatures::Signature_Summary`
|
|
notices are generated.
|
|
|
|
Redefinable Options
|
|
###################
|
|
.. zeek:id:: Signatures::count_thresholds
|
|
:source-code: base/frameworks/signatures/main.zeek 122 122
|
|
|
|
:Type: :zeek:type:`set` [:zeek:type:`count`]
|
|
:Attributes: :zeek:attr:`&redef`
|
|
:Default:
|
|
|
|
::
|
|
|
|
{
|
|
1000,
|
|
10000,
|
|
500,
|
|
5,
|
|
10,
|
|
100,
|
|
50,
|
|
1000000
|
|
}
|
|
|
|
|
|
Generate a notice if a :zeek:enum:`Signatures::SIG_COUNT_PER_RESP`
|
|
signature is triggered as often as given by one of these thresholds.
|
|
|
|
.. zeek:id:: Signatures::horiz_scan_thresholds
|
|
:source-code: base/frameworks/signatures/main.zeek 114 114
|
|
|
|
:Type: :zeek:type:`set` [:zeek:type:`count`]
|
|
:Attributes: :zeek:attr:`&redef`
|
|
:Default:
|
|
|
|
::
|
|
|
|
{
|
|
1000,
|
|
500,
|
|
5,
|
|
10,
|
|
100,
|
|
50
|
|
}
|
|
|
|
|
|
Generate a notice if, for a pair [orig, signature], the number of
|
|
different responders has reached one of the thresholds.
|
|
|
|
.. zeek:id:: Signatures::vert_scan_thresholds
|
|
:source-code: base/frameworks/signatures/main.zeek 118 118
|
|
|
|
:Type: :zeek:type:`set` [:zeek:type:`count`]
|
|
:Attributes: :zeek:attr:`&redef`
|
|
:Default:
|
|
|
|
::
|
|
|
|
{
|
|
1000,
|
|
500,
|
|
5,
|
|
10,
|
|
100,
|
|
50
|
|
}
|
|
|
|
|
|
Generate a notice if, for a pair [orig, resp], the number of
|
|
different signature matches has reached one of the thresholds.
|
|
|
|
State Variables
|
|
###############
|
|
.. zeek:id:: Signatures::actions
|
|
:source-code: base/frameworks/signatures/main.zeek 105 105
|
|
|
|
:Type: :zeek:type:`table` [:zeek:type:`string`] of :zeek:type:`Signatures::Action`
|
|
:Attributes: :zeek:attr:`&redef` :zeek:attr:`&default` = ``Signatures::SIG_ALARM``
|
|
:Default:
|
|
|
|
::
|
|
|
|
{
|
|
["unspecified"] = Signatures::SIG_IGNORE
|
|
}
|
|
|
|
|
|
Actions for a signature. Can be updated dynamically.
|
|
|
|
Types
|
|
#####
|
|
.. zeek:type:: Signatures::Action
|
|
:source-code: base/frameworks/signatures/main.zeek 44 70
|
|
|
|
:Type: :zeek:type:`enum`
|
|
|
|
.. zeek:enum:: Signatures::SIG_IGNORE Signatures::Action
|
|
|
|
Ignore this signature completely (even for scan detection).
|
|
Don't write to the signatures logging stream.
|
|
|
|
.. zeek:enum:: Signatures::SIG_QUIET Signatures::Action
|
|
|
|
Process through the various aggregate techniques, but don't
|
|
report individually and don't write to the signatures logging
|
|
stream.
|
|
|
|
.. zeek:enum:: Signatures::SIG_LOG Signatures::Action
|
|
|
|
Generate a notice.
|
|
|
|
.. zeek:enum:: Signatures::SIG_FILE_BUT_NO_SCAN Signatures::Action
|
|
|
|
The same as :zeek:enum:`Signatures::SIG_LOG`, but ignore for
|
|
aggregate/scan processing.
|
|
|
|
.. zeek:enum:: Signatures::SIG_ALARM Signatures::Action
|
|
|
|
Generate a notice and set it to be alarmed upon.
|
|
|
|
.. zeek:enum:: Signatures::SIG_ALARM_PER_ORIG Signatures::Action
|
|
|
|
Alarm once per originator.
|
|
|
|
.. zeek:enum:: Signatures::SIG_ALARM_ONCE Signatures::Action
|
|
|
|
Alarm once and then never again.
|
|
|
|
.. zeek:enum:: Signatures::SIG_COUNT_PER_RESP Signatures::Action
|
|
|
|
Count signatures per responder host and alarm with the
|
|
:zeek:enum:`Signatures::Count_Signature` notice if a threshold
|
|
defined by :zeek:id:`Signatures::count_thresholds` is reached.
|
|
|
|
.. zeek:enum:: Signatures::SIG_SUMMARY Signatures::Action
|
|
|
|
Don't alarm, but generate per-orig summary.
|
|
|
|
These are the default actions you can apply to signature matches.
|
|
All of them write the signature record to the logging stream unless
|
|
declared otherwise.
|
|
|
|
.. zeek:type:: Signatures::Info
|
|
:source-code: base/frameworks/signatures/main.zeek 72 102
|
|
|
|
:Type: :zeek:type:`record`
|
|
|
|
|
|
.. zeek:field:: ts :zeek:type:`time` :zeek:attr:`&log`
|
|
|
|
The network time at which a signature matching type of event
|
|
to be logged has occurred.
|
|
|
|
|
|
.. zeek:field:: uid :zeek:type:`string` :zeek:attr:`&log` :zeek:attr:`&optional`
|
|
|
|
A unique identifier of the connection which triggered the
|
|
signature match event.
|
|
|
|
|
|
.. zeek:field:: src_addr :zeek:type:`addr` :zeek:attr:`&log` :zeek:attr:`&optional`
|
|
|
|
The host which triggered the signature match event.
|
|
|
|
|
|
.. zeek:field:: src_port :zeek:type:`port` :zeek:attr:`&log` :zeek:attr:`&optional`
|
|
|
|
The host port on which the signature-matching activity
|
|
occurred.
|
|
|
|
|
|
.. zeek:field:: dst_addr :zeek:type:`addr` :zeek:attr:`&log` :zeek:attr:`&optional`
|
|
|
|
The destination host which was sent the payload that
|
|
triggered the signature match.
|
|
|
|
|
|
.. zeek:field:: dst_port :zeek:type:`port` :zeek:attr:`&log` :zeek:attr:`&optional`
|
|
|
|
The destination host port which was sent the payload that
|
|
triggered the signature match.
|
|
|
|
|
|
.. zeek:field:: note :zeek:type:`Notice::Type` :zeek:attr:`&log`
|
|
|
|
Notice associated with signature event.
|
|
|
|
|
|
.. zeek:field:: sig_id :zeek:type:`string` :zeek:attr:`&log` :zeek:attr:`&optional`
|
|
|
|
The name of the signature that matched.
|
|
|
|
|
|
.. zeek:field:: event_msg :zeek:type:`string` :zeek:attr:`&log` :zeek:attr:`&optional`
|
|
|
|
A more descriptive message of the signature-matching event.
|
|
|
|
|
|
.. zeek:field:: sub_msg :zeek:type:`string` :zeek:attr:`&log` :zeek:attr:`&optional`
|
|
|
|
Extracted payload data or extra message.
|
|
|
|
|
|
.. zeek:field:: sig_count :zeek:type:`count` :zeek:attr:`&log` :zeek:attr:`&optional`
|
|
|
|
Number of sigs, usually from summary count.
|
|
|
|
|
|
.. zeek:field:: host_count :zeek:type:`count` :zeek:attr:`&log` :zeek:attr:`&optional`
|
|
|
|
Number of hosts, from a summary count.
|
|
|
|
|
|
The record type which contains the column fields of the signature log.
|
|
|
|
Events
|
|
######
|
|
.. zeek:id:: Signatures::log_signature
|
|
:source-code: base/frameworks/signatures/main.zeek 132 132
|
|
|
|
:Type: :zeek:type:`event` (rec: :zeek:type:`Signatures::Info`)
|
|
|
|
This event can be handled to access/alter data about to be logged
|
|
to the signature logging stream.
|
|
|
|
|
|
:param rec: The record of signature data about to be logged.
|
|
|
|
Hooks
|
|
#####
|
|
.. zeek:id:: Signatures::log_policy
|
|
:source-code: base/frameworks/signatures/main.zeek 39 39
|
|
|
|
:Type: :zeek:type:`Log::PolicyHook`
|
|
|
|
A default logging policy hook for the stream.
|
|
|
|
|