Re: [PATCH v2] ssh signing: return an error when signature cannot be read

[Fabian Stelzer <fs@gigacodes.de>]

On 04.10.2022 10:01, Phillip Wood via GitGitGadget wrote:
>From: Phillip Wood <phillip.wood@dunelm.org.uk>
>
>If the signature file cannot be read we print an error message but do
>not return an error to the caller. In practice it seems unlikely that
>the file would be unreadable if the call to ssh-keygen succeeds.
>
>The unlink_or_warn() call is moved to the end of the function so that
>we always try and remove the signature file. This isn't strictly
>necessary at the moment but it protects us against any extra code
>being added between trying to read the signature file and the cleanup
>at the end of the function in the future. unlink_or_warn() only prints
>a warning if it exists and cannot be removed.

Sounds sensible and the change looks good to me.

>
>Signed-off-by: Phillip Wood <phillip.wood@dunelm.org.uk>
>---
>    ssh signing: return an error when signature cannot be read
>
>    Thanks to Junio for his comments. I've updated the patch to always use
>    unlink_or_warn() to remove the signature file as it does not warn on
>    missing files.
>
>    V1 cover letter
>
>    This patch is based on maint. In the longer term the code could be
>    simplified by using pipes rather than tempfiles as we do for gpg.
>    ssh-keygen has supported reading the data to be signed from stdin and
>    writing the signature to stdout since it introduced signing.

The ssh-keygen call is already using stdin for the content to sign or 
verify. The signature and the signing key need to be files passed as 
parameters to ssh-keygen. I'm not aware of any other option of providing 
them to it.

Cheers,
Fabian