Re: ssl passphrase callback

On Wed, Nov 13, 2019 at 01:20:43PM +0000, Simon Riggs wrote:
>On Wed, 13 Nov 2019 at 13:08, Bruce Momjian <bruce(at)momjian(dot)us> wrote:
>
>> On Tue, Nov 12, 2019 at 09:51:33PM -0500, Bruce Momjian wrote:
>> > On Sun, Nov 10, 2019 at 01:01:17PM -0600, Magnus Hagander wrote:
>> > > On Wed, Nov 6, 2019 at 7:24 PM Bruce Momjian <bruce(at)momjian(dot)us> wrote:
>>
>> > > One of the main reasons there being to be easily able to transfer more
>> state
>> > > and give results other than just an exit code, no need to deal with
>> parameter
>> > > escaping etc. Which probably wouldn't matter as much to an SSL
>> passphrase
>> > > command, but still.
>> >
>> > I get the callback-is-easier issue with shared objects, but are we
>> > expecting to pass in more information here than we do for
>> > archive_command? I would think not. What I am saying is that if we
>> > don't think passing things in works, we should fix all these external
>> > commands, or something. I don't see why ssl_passphrase_command is
>> > different, except that it is new.
>
>
>
>> Or is it related to _securely_passing something?
>>
>
>Yes
>

I think it would be beneficial to explain why shared object is more
secure than an OS command. Perhaps it's common knowledge, but it's not
quite obvious to me.

>
>> > Also, why was this patch posted without any discussion of these issues?
>> > Shouldn't we ideally discuss the API first?
>>
>> I wonder if every GUC that takes an OS command should allow a shared
>> object to be specified --- maybe control that if the command string
>> starts with a # or something.
>>
>
>Very good idea
>

If it's about securely passing sensitive information (i.e. passphrase)
as was suggested, then I think that only applies to fairly small number
of GUCs.

regards

--
Tomas Vondra http://www.2ndQuadrant.com
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