Previously, Zeek treated the receipt of `AuthenticationOk` as a
successful login. However, according to the PostgreSQL
Frontend/Backend Protocol, the startup phase is not complete until
the server sends `ReadyForQuery`. It is still possible for the server
to emit an `ErrorResponse` (e.g. ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION)
after `AuthenticationOk` but before `ReadyForQuery`.
This change updates the PostgreSQL analyzer to defer reporting login
success until `ReadyForQuery` is observed. This prevents false
positives in cases where authentication succeeds but session startup
fails.
While we support initializing records via coercion from an expression
list, e.g.,
local x: X = [$x1=1, $x2=2];
this can sometimes obscure the code to readers, e.g., when assigning to
value declared and typed elsewhere. The language runtime has a similar
overhead since instead of just constructing a known type it needs to
check at runtime that the coercion from the expression list is valid;
this can be slower than just writing the readible code in the first
place, see #4559.
With this patch we use explicit construction, e.g.,
local x = X($x1=1, $x2=2);
This adds a protocol parser for the PostgreSQL protocol and a new
postgresql.log similar to the existing mysql.log.
This should be considered preliminary and hopefully during 7.1 and 7.2
with feedback from the community, we can improve on the events and logs.
Even if most PostgreSQL communication is encrypted in the real-world, this
will minimally allow monitoring of the SSLRequest and hand off further
analysis to the SSL analyzer.
This originates from github.com/awelzel/spicy-postgresql, with lots of
polishing happening in the past two days.
