On 30.07.21 00:28, Randall S. Becker wrote:
On July 29, 2021 5:29 PM, Fabian Stelzer wrote:
On 29.07.21 23:25, Randall S. Becker wrote:
On July 29, 2021 5:13 PM, Fabian Stelzer wrote:
Subject: Re: [PATCH v6 5/9] ssh signing: parse ssh-keygen output and
verify signatures
On 29.07.21 23:01, Randall S. Becker wrote:
On July 29, 2021 4:46 PM, Junio wrote:
Fabian Stelzer <fs@xxxxxxxxxxxx> writes:
On 29.07.21 01:04, Jonathan Tan wrote:
Also, is this output documented to be stable even across locales?
Not really :/ (it currently is not locale specific)
We probably want to defeat l10n of the message by spawning it in the C locale regardless.
The documentation states to only check the commands exit code. Do
we trust the exit code enough to rely on it for verification?
Is the exit code sufficient to learn who signed it? Without
knowing that, we cannot see if the principal is in or not in our
keychain, no?
Have we not had issues in the past depending on exit code? I'm not sure this can be made entirely portable.
To find the principal (who signed it) we don't have to parse the output.
Since verification is first a call to look up the principals matching
the signatures public key from the allowedSignersFile and then trying
verification with each one we already know which one matched (usually there is only one. I think multiples is only possible with an SSH
CA).
Of course this even more relies on the exit code of ssh-keygen.
Not sure which is more portable and reliable. Parsing the textual output or the exit code. At the moment my patch does both.
What about a configurable exit code for this? See the comment below about that.
I'm not sure what you mean. Something like "treat exit(123) as success"?
How about gpg.ssh.successExit=123 or something like that.
I don't quite understand what the benefit would be. Do you have any
specific portability problems/concerns where the ssh-keygen format is
different or exit codes differ?
I think using a script that provides exit(0) on success and the correct
output to wrap ssh-keygen and setting it in gpg.ssh.command can already
cover edge cases when needed.
Is there documentation on the possible arguments the patch series will use for this so one can create a wrapper script? I had to look into the code to find out what GIT_SSH_COMMAND actually required when the ssh variant was "ssh". I'd rather not have to do that in this case.
The documentation in ssh-keygen(1) is quite good and straight forward
for verification and signing. Again if you have any specific portability
concerns i'd be glad to help.
