Git silently broke push-options over ssh?

Git silently broke push-options over ssh?

[Sven Strickroth]

Hi,

I'm using Git (for Windows) 2.33.1 and using push-options as described 
on <https://docs.gitlab.com/ee/user/project/push_options.html> does not 
work any more (IIRC it used to work with Git 2.16 and 2.17).

If I understood 
<https://opensource.googleblog.com/2018/05/introducing-git-protocol-version-2.html> 
correctly I have to enable the Git protocol version 2 and then the push 
options should work.

Now, when I try to use push options on Windows it does not work. I tried 
to debug it:

D:\TortoiseGit>set GIT_TRACE=2
D:\TortoiseGit>set GIT_SSH=ssh.exe
D:\TortoiseGit>set GIT_SSH_VARIANT=ssh
D:\TortoiseGit>set GIT_PROTOCOL=version=2
D:\TortoiseGit>git -c protocol.version=2 -c ssh.variant=ssh -c 
ssh.command=ssh push -v -o ci.skip origin master~23:testing
17:36:06.285346 exec-cmd.c:237          trace: resolved executable dir: 
C:/Program Files/Git/mingw64/bin
17:36:06.285346 git.c:455               trace: built-in: git push -v -o 
ci.skip origin 'master~23:testing'
Pushing to gitlab.com:tortoisegit/tortoisegit.git
17:36:06.295270 run-command.c:666       trace: run_command: unset 
GIT_CONFIG_PARAMETERS GIT_PREFIX; ssh.exe git@gitlab.com 
'git-receive-pack '\''tortoisegit/tortoisegit.git'\'''

As you can see, the "-o SendEnv" parameter not passed to ssh.exe and, 
therefore, I think the push option is not transferred to the server.

According to <https://github.com/git-for-windows/git/issues/3486> the 
reason is a commit that was shipped with Git 2.18 (in 2018):

<https://github.com/git/git/commit/1aa8dded3afff28d8f4c24a97b237a0d9e633173>

How to use push options with Git over SSH?

-- 
Best regards,
  Sven Strickroth
  PGP key id F5A9D4C4 @ any key-server

Re: Git silently broke push-options over ssh?

[Jeff King]

On Fri, Oct 22, 2021 at 07:27:14PM +0200, Sven Strickroth wrote:

> If I understood <https://opensource.googleblog.com/2018/05/introducing-git-protocol-version-2.html>
> correctly I have to enable the Git protocol version 2 and then the push
> options should work.

I don't think that is true. There is no v2 push protocol yet, so the
push options must work over v0.

> Now, when I try to use push options on Windows it does not work. I tried to
> debug it:
> 
> D:\TortoiseGit>set GIT_TRACE=2
> D:\TortoiseGit>set GIT_SSH=ssh.exe
> D:\TortoiseGit>set GIT_SSH_VARIANT=ssh
> D:\TortoiseGit>set GIT_PROTOCOL=version=2
> D:\TortoiseGit>git -c protocol.version=2 -c ssh.variant=ssh -c
> ssh.command=ssh push -v -o ci.skip origin master~23:testing
> 17:36:06.285346 exec-cmd.c:237          trace: resolved executable dir:
> C:/Program Files/Git/mingw64/bin
> 17:36:06.285346 git.c:455               trace: built-in: git push -v -o
> ci.skip origin 'master~23:testing'
> Pushing to gitlab.com:tortoisegit/tortoisegit.git
> 17:36:06.295270 run-command.c:666       trace: run_command: unset
> GIT_CONFIG_PARAMETERS GIT_PREFIX; ssh.exe git@gitlab.com 'git-receive-pack
> '\''tortoisegit/tortoisegit.git'\'''
> 
> As you can see, the "-o SendEnv" parameter not passed to ssh.exe and,
> therefore, I think the push option is not transferred to the server.

Push options don't go through the environment. The GIT_PROTOCOL magic
for enabling v2 does, but push options themselves happen over the Git
protocol. Try GIT_TRACE_PACKET for seeing the actual conversation. E.g.:

  $ GIT_TRACE_PACKET=1 GIT_TRACE=1 git push -o foo git.peff.net:foo.git
  16:49:19.236448 git.c:455               trace: built-in: git push -o foo git.peff.net:foo.git
  16:49:19.237409 run-command.c:666       trace: run_command: unset GIT_PREFIX; ssh git.peff.net 'git-receive-pack '\''foo.git'\'''
  16:49:19.423323 pkt-line.c:80           packet:         push< b2f0a7f47f5f2aebe1e7fceff19a57de20a78c06 refs/heads/master\0report-status report-status-v2 delete-refs side-band-64k quiet atomic ofs-delta push-options object-format=sha1 agent=git/2.30.2
  16:49:19.423399 pkt-line.c:80           packet:         push< 0000
  16:49:19.431385 pkt-line.c:80           packet:         push> 0000
  16:49:19.431421 pkt-line.c:80           packet:         push> foo
  16:49:19.431442 pkt-line.c:80           packet:         push> 0000
  Everything up-to-date

On the server side, receive-pack will stick them in the environment to
communicate them to hooks, etc, but you wouldn't be able to see that
from the client.

Do note that I had to set receive.advertisePushOptions on the server to
make it work (though if it's not set, the client should complain
loudly). If you're pushing to gitlab.com they've presumably set up the
server side appropriately.

-Peff

Re: Git silently broke push-options over ssh?

[Sven Strickroth]

Am 22.10.2021 um 22:53 schrieb Jeff King:
> On Fri, Oct 22, 2021 at 07:27:14PM +0200, Sven Strickroth wrote:
> 
>> If I understood <https://opensource.googleblog.com/2018/05/introducing-git-protocol-version-2.html>
>> correctly I have to enable the Git protocol version 2 and then the push
>> options should work.
> 
> I don't think that is true. There is no v2 push protocol yet, so the
> push options must work over v0.

You are right. After enabling GIT_TRACE_PACKET I see that the 
push-option gets transmitted correctly.

I got confused was because a GitLab CI pipeline run despite I passed 
ci.skip. The reason why the pipeline ran despite of that flag is that 
some external push hook triggered a CI pipeline action manually - when I 
look at GitLab immediately after the push I see that the pipeline is 
skipped and then the external hook fires...

Thanks for the hint for enabling GIT_TRACE_PACKET  Peff and sorry for 
the noise.

  Sven