8.35. Quic Keywords

Suricata implements initial support for Quic by parsing the Quic version.

Suricata also derives a CYU hash for earlier versions of Quic.

Quic app-layer parsing must be enabled in the Suricata config file (set 'app-layer.protocols.quic.enabled' to 'yes').

8.35.1. quic.cyu.hash

Match on the CYU hash

Examples:

alert quic any any -> any any (msg:"QUIC CYU HASH"; \
  quic.cyu.hash; content:"7b3ceb1adc974ad360cfa634e8d0a730"; \
  sid:1;)

quic.cyu.hash supports multiple buffer matching, see Multiple Buffer Matching.

8.35.2. quic.cyu.string

Match on the CYU string

Examples:

alert quic any any -> any any (msg:"QUIC CYU STRING"; \
  quic.cyu.string; content:"46,PAD-SNI-VER-CCS-UAID-TCID-PDMD-SMHL-ICSL-NONP-MIDS-SCLS-CSCT-COPT-IRTT-CFCW-SFCW"; \
  sid:2;)

quic.cyu.string supports multiple buffer matching, see Multiple Buffer Matching.

8.35.3. quic.version

Sticky buffer for matching on the Quic header version in long headers.

Examples:

alert quic any any -> any any (msg:"QUIC VERSION"; \
  quic.version; content:"Q046"; \
  sid:3;)

8.35.4. Additional information

More information on CYU Hash can be found here: https://engineering.salesforce.com/gquic-protocol-analysis-and-fingerprinting-in-zeek-a4178855d75f

More information on the protocol can be found here: https://datatracker.ietf.org/doc/html/draft-ietf-quic-transport-17