SSL/TLS Keywords ================ Suricata comes with several rule keywords to match on various properties of TLS/SSL handshake. Matches are string inclusion matches. tls.version ----------- Match on negotiated TLS/SSL version. Example values: "1.0", "1.1", "1.2" Support added in Suricata version 1.3. tls.subject ----------- Match TLS/SSL certificate Subject field. example: :: tls.subject:"CN=*.googleusercontent.com" Support added in Suricata version 1.3. Case sensitve, can't use 'nocase'. tls.issuerdn ------------ match TLS/SSL certificate IssuerDN field example: :: tls.issuerdn:!"CN=Google-Internet-Authority" Support added in Suricata version 1.3. Case sensitve, can't use 'nocase'. tls.fingerprint --------------- match TLS/SSL certificate SHA1 fingerprint example: :: tls.fingerprint:!"f3:40:21:48:70:2c:31:bc:b5:aa:22:ad:63:d6:bc:2e:b3:46:e2:5a" Support added in Suricata version 1.4. Case sensitive, can't use 'nocase'. The tls.fingerprint buffer is lower case so you must use lower case letters for this to match. tls.store --------- store TLS/SSL certificate on disk Support added in Suricata version 1.4. ssl_state --------- The ``ssl_state`` keyword matches the state of the SSL connection. The possible states are ``client_hello``, ``server_hello``, ``client_keyx``, ``server_keyx`` and ``unknown``. You can specify several states with ``|`` (OR) to check for any of the specified states. Negation support is not available yet, see https://redmine.openinfosecfoundation.org/issues/1231