Gpg-agent socket activation stopped working

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1

A few months ago gpg stopped working for me. The symptoms are that it can not find a pinentry program. I can work around this by manually starting the agent, however, I have the following in my configuration.nix which should start it for me.

  programs.gnupg.agent = {
    enable = true;
    enableSSHSupport = true;
  };

However, journalctl --user -u gpg-agent suggests that the service has not been activated since Sep 21.

$ systemctl --user status gpg-agent.service
○ gpg-agent.service - GnuPG cryptographic agent and passphrase cache
     Loaded: loaded (/etc/systemd/user/gpg-agent.service; linked-runtime; vendor preset: enab>
    Drop-In: /nix/store/plawdzg6rj2993finc1nb0lnkls3ympw-user-units/gpg-agent.service.d
             └─overrides.conf
     Active: inactive (dead)
       Docs: man:gpg-agent(1)

Ok, so I try and start it

$ systemctl --user start gpg-agent.service
Failed to start gpg-agent.service: Unit gpg-agent.socket not found.

And indeed

$ systemctl --user status gpg-agent.socket
Unit gpg-agent.socket could not be found.

Poking around in the directories:

$ cat /etc/systemd/user/gpg-agent.socket
[Unit]
Description=GnuPG cryptographic agent and passphrase cache
Documentation=man:gpg-agent(1)

[Socket]
ListenStream=%t/gnupg/S.gpg-agent
FileDescriptorName=std
SocketMode=0600
DirectoryMode=0700

[Install]
WantedBy=sockets.target

$ cat /etc/systemd/user/gpg-agent.socket.d/overrides.conf
[Unit]

[Socket]

Any ideas why the socket activation is suddenly broken?

2

Have you tried explicitly setting programs.gnupg.agent.pinentryFlavor? The documentation says it should default to curses if not set and X11 is not enabled, but indeed the gpg-agent.service is only configured if pinentryFlavor is not null.

3

It unfortunately makes no difference. pinentryFlavor is not null by default, so the case were the service isn’t enabled due to pinentryFlavor being null would be hard to hit.

4

So, it turned out that something had generated some files in ~/.config/systemd which seemed to be overriding the systemd user services set up by NixOS (including gpg-agent). I don’t know what caused those to be created, but they had links into the nix store. I simply deleted the whole ~/config/systemd directory and the problem was solved.