Re: can we mark upper/lower/textlike functions leakproof?

On 7/31/24 16:10, Robert Haas wrote:
> On Wed, Jul 31, 2024 at 2:43 PM Joe Conway <mail(at)joeconway(dot)com> wrote:
>> I still maintain that there is a whole host of users that would accept
>> the risk of side channel attacks via existence of an error or not, if
>> they could only be sure nothing sensitive leaks directly into the logs
>> or to the clients. We should give them that choice.
>
> I'm not sure what design you have in mind. A lot of possible designs
> seem to end up like this:
>
> 1. You can't directly select the invisible value.
>
> 2. But you can write a plpgsql procedure that tries a bunch of things
> in a loop and catches errors and uses which things error and which
> things don't to figure out and return the invisible value.
>
> And I would argue that's not really that useful. Especially if that
> plpgsql procedure can extract the hidden values in like 1ms/row.

You are assuming that everyone allows direct logins with the ability to
create procedures. Plenty don't.

--
Joe Conway
PostgreSQL Contributors Team
RDS Open Source Databases
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