Handler.options should only be cleared when the connection ends

[rendaw]

I think.

The first time I invoke gpg, the agent gets OPTIONs, the commands to sign/encrypt/get key/whatever, then RESET is passed time.

The 2nd time and after I invoke gpg, the gpg agent is sent RESET after the HAVEKEY's finish, and before PKSIGN, so the pinentry doesn't get any options.

It looks like in the GPG code all options are kept until the client connection is closed via session_env_* commands:
session_env_new is called here: https://github.com/gpg/gnupg/blob/f574aabeeb873f14a586f80cac16b857e6088534/agent/gpg-agent.c#L3079
Then a thread to handle the connection is started which eventually gets to this:
https://github.com/gpg/gnupg/blob/f574aabeeb873f14a586f80cac16b857e6088534/agent/gpg-agent.c#L2708 - start_command_handler runs until EOF handling assuan commands, then agent_deinit_default_ctrl calls session_env_release.

At least, I think that's the issue. Right now my pinentry is failing to appear unless I restart trezor-gpg-agent in any case.

[romanz]

Thanks for reporting this issue!

Could you please attach the logs (from ~/.gnupg/trezor/gpg-agent.log)?
I am not sure I understand the scenario, since on my machine (Ubuntu 17.10, gnupg 2.1.15) the code seems to work as intended.

[rendaw]

Yeah sure: https://gist.github.com/rendaw/0a079ba4511aeb8ec5aa3c5f9a979dd1

To demonstrate the issue I did:

gpg --sign ~/a.txt
(unplug trezor and plug in again to cause cache to clear)
gpg --sign ~/a.txt

The second time the pinentry didn't appear. Waiting 5 minutes or whatever before signing works too. Basically only the first gpg use with pinentry after starting the agent works.

If your trezor-gpg-agent started with DISPLAY in the environment it might be falling back to that.

[romanz]

Great catch - thanks a lot for the debugging!

[romanz]

Please take a look :)

[rendaw]

Whoops, sorry for the delay. The fix is working great for me!

[romanz]

You're welcome :)