Re: [PATCH 1/1] verify-tag/verify-commit should exit unsuccessfully when signature is not trusted

On Wed, Aug 08, 2018 at 05:59:43PM -0700, Junio C Hamano wrote:

"brian m. carlson" [off-list ref] writes:

quoted

quoted

FWIW, I'm on board with returning non-zero in any case where gpg would.

I think that's probably the best solution overall.

FWIW, I am not married to the current behaviour.  I would not be
surprised if it mostly came by accident and not designed.

Since apparently I was the author of the commit that changed the
behavior originally, let me simply say that I was not aware that gpg
signalled the correctness of a signature by its exit status when I wrote
that patch.  If I had known that, I would have deferred to gpg in my
change.  My goal was consistency between verify-tag and verify-commit,
and in retrospect I probably made the wrong decision.

quoted

There's a bug report
in Debian (https://bugs.debian.org/895048) that requests that behavior
instead of the status quo, and also it's the behavior that's documented:

The last bit is a bit questionable; I think you are reading too much
into the description.

A substitute for gpg.program MUST signal good (or not good)
signature the same way as gpg would with its exit code---that is all
the description says.  It does not say anything about how that exit
code affects the exit status of "tag --verify" and friends that
called gpg.program.

I agree that the description doesn't specifically say that.  In fact, it
doesn't explicitly say that it must exit nonzero on a bad signature,
although I agree with your interpretation that that would be logical
(and, AIUI, the behavior of gpg).

However, I would assert that we do want Git's verification to exit
successfully on a good signature and unsuccessfully on a bad signature,
and deferring to gpg may be the most robust way of ensuring that.
-- 
brian m. carlson: Houston, Texas, US
OpenPGP: https://keybase.io/bk2204