JA3/JA4 Keywords
================

Suricata comes with JA3 (https://github.com/salesforce/ja3) and 
JA4 (https://github.com/FoxIO-LLC/ja4) integration.
JA3 and JA4 are used to fingerprint TLS and QUIC clients.

Support must be enabled in the Suricata config file (set
``app-layer.protocols.tls.ja{3,4}-fingerprints`` to ``yes``). If it is not
explicitly disabled (``no``) , it will be enabled if a loaded rule requires it.
Note that JA3/JA4 support can also be disabled at compile time; it is possible to
use the ``requires: feature ja{3,4};`` keyword to skip rules if no JA3/JA4 support is
present.

ja3.hash
--------

Match on JA3 hash (md5).

Example::

  alert tls any any -> any any (msg:"match JA3 hash"; \
      ja3.hash; content:"e7eca2baf4458d095b7f45da28c16c34"; \
      sid:100001;)

``ja3.hash`` is a 'sticky buffer'.

``ja3.hash`` can be used as ``fast_pattern``.

``ja3.hash`` replaces the previous keyword name: ``ja3_hash``. You may continue
to use the previous name, but it's recommended that rules be converted to use
the new name.

ja3.string
----------

Match on JA3 string.

Example::

  alert tls any any -> any any (msg:"match JA3 string"; \
      ja3.string; content:"19-20-21-22"; \
      sid:100002;)

``ja3.string`` is a 'sticky buffer'.

``ja3.string`` can be used as ``fast_pattern``.

``ja3.string`` replaces the previous keyword name: ``ja3_string``. You may continue
to use the previous name, but it's recommended that rules be converted to use
the new name.

ja3s.hash
---------

Match on JA3S hash (md5).

Example::

  alert tls any any -> any any (msg:"match JA3S hash"; \
      ja3s.hash; content:"b26c652e0a402a24b5ca2a660e84f9d5"; \
      sid:100003;)

``ja3s.hash`` is a 'sticky buffer'.

``ja3s.hash`` can be used as ``fast_pattern``.

ja3s.string
-----------

Match on JA3S string.

Example::

  alert tls any any -> any any (msg:"match on JA3S string"; \
      ja3s.string; content:"771,23-35"; sid:100004;)

``ja3s.string`` is a 'sticky buffer'.

``ja3s.string`` can be used as ``fast_pattern``.

ja4.hash
--------

Match on JA4 hash (e.g. ``q13d0310h3_55b375c5d22e_cd85d2d88918``).

Example::

  alert quic any any -> any any (msg:"match JA4 hash"; \
      ja4.hash; content:"q13d0310h3_55b375c5d22e_cd85d2d88918"; \
      sid:100001;)

``ja4.hash`` is a 'sticky buffer'.

``ja4.hash`` can be used as ``fast_pattern``.