`FirstPacket()` so far supported only TCP. To extend this to UDP, we
move the method into the PIA base class; give it a protocol parameter
for the case that there's no actual packet is available; and add the
ability to create fake UDP packets as well, not just TCP.
This whole thing is pretty ugly to begin with, and this doesn't make
it nicer, but we need this extension that so we can feed UDP data into
the signature engine that's tunneled over other protocols. Without the
fake packets, DPD signatures in particular wouldn't have anything to
match on.
The Spicy analyzer is added as a child analyzer when enabled and the
WebSocket.cc logic dispatches between the BinPac and Spicy version.
It substantially slower when tested against a somewhat artificial
2.4GB PCAP. The first flamegraph indicates that the unmask() function
stands out with 35% of all samples, and above it shared_ptr samples.
Don't log them, they are random and arbitrary in the normal case. Users
can do the following to log them if wanted.
redef += WebSocket::Info$client_key += { &log };
redef += WebSocket::Info$server_accept += { &log };
This adds a new WebSocket analyzer that is enabled with the HTTP upgrade
mechanism introduced previously. It is a first implementation in BinPac with
manual chunking of frame payload. Configuration of the analyzer is sketched
via the new websocket_handshake() event and a configuration BiF called
WebSocket::__configure_analyzer(). In short, script land collects WebSocket
related HTTP headers and can forward these to the analyzer to change its
parsing behavior at websocket_handshake() time. For now, however, there's
no actual logic that would change behavior based on agreed upon extensions
exchanged via HTTP headers (e.g. frame compression). WebSocket::Configure()
simply attaches a PIA_TCP analyzer to the WebSocket analyzer for dynamic
protocol detection (or a custom analyzer if set). The added pcaps show this
in action for tunneled ssh, http and https using wstunnel. One test pcap is
Broker's WebSocket traffic from our own test suite, the other is the
Jupyter websocket traffic from the ticket/discussion.
This commit further adds a basic websocket.log that aggregates the WebSocket
specific headers (Sec-WebSocket-*) headers into a single log.
Closes#3424
