[pkg-gnupg-maint] Bug#842908: gnupg: with no $DISPLAY: problem with the agent: Configuration error

[Vincent Lefevre]

Package: gnupg
Version: 2.1.15-8
Severity: grave
Justification: renders package unusable

gpg no longer works without a $DISPLAY.

For instance:

1. SSH to some machine (without X forwarding and without a running
   X session).

2. Make sure that gpg-agent is not running (or kill it).

3. Run something like: "gpg -d file.gpg" on an encrypted file.

I get:

cventin:~> gpg -d file.gpg
gpg: AES encrypted data
gpg: problem with the agent: Configuration error
gpg: encrypted with 1 passphrase
gpg: decryption failed: No secret key

This is a much more general problem than bug 842015 (which is about
a conflict with an already running gpg-agent). Here, gpg over SSH
is completely broken. This is a severe regression and must be fixed
before the next stable release.

Note: If I try from an X session after killing the current gpg-agent
and unsetting DISPLAY, pinentry is run on the X display, which wasn't
really expected since DISPLAY is unset!

-- System Information:
Debian Release: stretch/sid
  APT prefers unstable-debug
  APT policy: (500, 'unstable-debug'), (500, 'stable-updates'), (500, 'unstable'), (500, 'testing'), (500, 'stable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.7.0-1-amd64 (SMP w/12 CPU cores)
Locale: LANG=POSIX, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages gnupg depends on:
ii  gnupg-agent    2.1.15-8
ii  libassuan0     2.4.3-1
ii  libbz2-1.0     1.0.6-8
ii  libc6          2.24-5
ii  libgcrypt20    1.7.3-2
ii  libgpg-error0  1.24-1
ii  libksba8       1.3.5-2
ii  libreadline7   7.0-1
ii  libsqlite3-0   3.15.0-1
ii  zlib1g         1:1.2.8.dfsg-2+b3

Versions of packages gnupg recommends:
ii  dirmngr     2.1.15-8
ii  gnupg-l10n  2.1.15-8

Versions of packages gnupg suggests:
pn  parcimonie  <none>
pn  xloadimage  <none>

-- no debconf information