gnupg arch pinentry

masen, 13 November 2013

I always get a pleasant feeling when I recieve a PGP encrypted file or message, but the message isn't much good if I can't read it. Unfortunately, as I receive so few of such messages, my setup decays without daily use and becomes broken.

gnupg logo

Case in point: Decrypting a message using GnuPG on a headless Arch Linux box:

Case in point 2 (added 2015-04-10): this just happened again, I should maybe submit a patch?

  • gnupg has a dependency on pinentry
  • the pinentry package in Arch has this closed bug (closed as 'not a bug', you need to install the appropriate optdepends -- my ass)
  • "The PKGBUILD deletes pinetry and symlinks it to pinentry-gtk-2"
  • This is still an issue with the latest packages
  • Today manifesting itself in the following error message:

    pinentry: error while loading shared libraries: libgtk-x11-2.0.so.0: cannot open shared object file: No such file or directory
    gpg-agent[1652]: can't connect to the PIN entry module: End of file
    gpg-agent[1652]: command get_passphrase failed: No pinentry
    gpg: problem with the agent: No pinentry
    

The solution is ridiculously simple, and I'm surprised that no action was taken to resolve the bug three years ago when it was reported. At any rate:

# rm /usr/bin/pinentry && ln -s pinentry-curses /usr/bin/pinentry

You may also need to set the TTY if you see the following message when trying to use gpg (source):

pinentry-curses: no LC_CTYPE known assuming UTF-8

Ensure that you are the owner of the current TTY:

ls -l $(tty)

Take ownership if necessary:

chown masen $(tty)

Tell gpg where to tell pinentry to draw its box:

export GPG_TTY=$(tty)

After that, I was able to use gpg to enter my key passphrase. If you don't use a passphrase, this obviously won't be a problem for you. If you don't use a passphrase, you should.