[pkg-gnupg-maint] Bug#850708: Bug#850708: gpg: decryption failed: No secret key

[Vincent Lefevre]

On 2017-01-11 01:47:53 -0500, Daniel Kahn Gillmor wrote:
> hm, both Vincent and gi1242 are using fvwm.  can you try installing
> openbox or some other comparable minimalist window manager and let me
> know whether you still see the same misbehavior?  it sounds to me like
> y'all might have hit on a combination of tools (fvwm + pinentry-gtk2)
> that don't work well together.

Note that when a Fvwm operation is done (like when the pinentry window
is being opened?), Fvwm may grab the mouse pointer, as documented in
the fvwm(1) man page:

SCRIPTING & COMPLEX FUNCTIONS
       To achieve the more complex effects, fvwm has a number of
       commands that improve its scripting abilities.  Scripts can be
       read from a file with Read, from the output of a command with
       PipeRead or written as a complex function with the AddToFunc
       command.  For the curious, section 7 of the fvwm FAQ shows some
       real life applications of scripting.  Please refer to the
       sections User Functions and Shell Commands and Conditional
       Commands for details.  A word of warning: during execution of
       complex functions, fvwm needs to take all input from the mouse
       pointer (the pointer is "grabbed" in the slang of X).  No other
                ^^^^^^^^^^^^^^^^^^^^^^^^
       programs can receive any input from the pointer while a function
       is run.  This can confuse some programs.  For example, the xwd
       program refuses to make screen shots when run from a complex
       function.  To achieve the same functionality you can use the Read
       or PipeRead command instead.

So, the application may need to wait a little bit instead of failing
immediately (I suppose that the problem is more visible on multicore
machines).

In the /usr/share/doc/pinentry-gtk2/changelog.gz, I can see that they
had problems with keyboard grabbing in general, and for the pointer,
this is newer:

2016-08-02  Justus Winter  <justus at g10code.com>

        gtk2: Also grab the pointer.
        * gtk+-2/pinentry-gtk-2.c (grab_pointer): New function.
        (ungrab_keyboard): Rename to 'ungrab_inputs' and also release the
        pointer grab.
        (create_window): Also grab the pointer.

        GnuPG-bug-id: 2430

2016-08-01  Justus Winter  <justus at g10code.com>

        gtk2: Be more persistent trying to grab the keyboard.
        We seem to get the 'visibility-notify' event before X is willing to
        let us grab the keyboard, insisting that the target window is not
        viewable (sic).

        * gtk+-2/pinentry-gtk-2.c (grab_keyboard): Retry grabbing the
        keyboard.
[...]

> can you try pinentry-qt as well?  does it have the same problem?

No problems with pinentry-qt, but it does not try to grab the pointer.

> Vincent has been unable to replicate the problem with:
> 
>  * fvwm + pinentry-curses

Same reason: no pointer grab.

-- 
Vincent Lefèvre <vincent at vinc17.net> - Web: <https://www.vinc17.net/>
100% accessible validated (X)HTML - Blog: <https://www.vinc17.net/blog/>
Work: CR INRIA - computer arithmetic / AriC project (LIP, ENS-Lyon)