Re: Password leakage avoidance

Having worked on and just about wrapped up the JDBC driver patch for this,
couple thoughts:

1. There's two sets of defaults, the client program's default and the
server's default. Need to pick one for each implemented function. They
don't need to be the same across the board.
2. Password encoding should be split out and made available as its own
functions. Not just as part of a wider "create _or_ alter a user's
password" function attached to a connection. We went a step further and
added an intermediate function that generates the "ALTER USER ... PASSWORD"
SQL.
3. We only added an "ALTER USER ... PASSWORD" function, not anything to
create a user. There's way too many options for that and keeping this
targeted at just assigning passwords makes it much easier to test.
4. RE:defaults, the PGJDBC approach is that the encoding-only function uses
the driver's default (SCRAM). The "alterUserPassword(...)" uses the
server's default (again usually SCRAM for modern installs but could be
something else). It's kind of odd that they're different but the use cases
are different as well.
5. Our SCRAM specific function allows for customizing the algo iteration
and salt parameters. That topic came up on hackers previously[1]. Our high
level "alterUserPassword(...)" function does not have those options but it
is available as part of our PasswordUtil SCRAM API for advanced users who
want to leverage it. The higher level functions have defaults for iteration
counts (4096) and salt size (16-bytes).
6. Getting the verbiage right for the PGJDBC version was kind of annoying
as we wanted to match the server's wording, e.g. "password_encryption", but
it's clearly hashing, not encryption. We settled on "password encoding" for
describing the overall task with the comments referencing the server's
usage of the term "password_encryption". Found a similar topic[2] on
changing that recently as well but looks like that's not going anywhere.

[1]:
https://www.postgresql.org/message-id/1d669d97-86b3-a5dc-9f02-c368bca911f6%40iki.fi
[2]:
https://www.postgresql.org/message-id/flat/ZV149Fd2JG_OF7CM%40momjian.us#cc97d20ff357a9e9264d4ae14e96e566

Regards,
-- Sehrope Sarkuni
Founder & CEO | JackDB, Inc. | https://www.jackdb.com/