zeek/testing/btest/Traces/tls/chrome-63.0.3211.0-canary-tls_experiment.pcap
Johanna Amann 1ede6bf7fe Add TLS 1.3 fix and testcase.
It turns out that Chrome supports an experimental mode to support TLS
1.3, which uses a non-standard way to negotiate TLS 1.3 with a server.
This non-standard way to negotiate TLS 1.3 breaks the current draft RFC
and re-uses an extension on the server-side with a different binary
formatting, causing us to throw a binpac exception.

This patch ignores the extension when sent by the server, continuing to
correctly parse the server_hello reply (as far as possible).

From what I can tell this seems to be google working around the fact
that MITM equipment cannot deal with TLS 1.3 server hellos; this change
makes the fact that TLS 1.3 is used completely opaque unless one looks
into a few extensions.

We currently log this as TLS 1.2.
2017-09-09 22:25:49 -07:00

5.2 KiB