Get pinentry to work in a container

[zyxhere💭]

On Sun, 2025-08-31 at 01:41 +0500, zyxhere💭 via Gnupg-users wrote:
> Hi! I have created a container for development purposes with
> bubblewrap[1] and unshare, so far it has been working great
> the only thing that isn't working is gpg signed commits with
> git I have bind mounted the $GNUPGHOME into the container
> and gpg can see it with gpg --list-keys. Now when I sign
> commits with it I gett:
> ```
> gpg: signing failed: Inappropriate ioctl for device
> ```
> 
> This was fixed by adding `export GPG_TTY=$(tty)` to
> ~/.bash_profile ($(tty) points to /dev/console).But now
> I get:
> ```
> localhost # git commit -s -S -a -m "test"
> error: gpg failed to sign the data:
> gpg: WARNING: unsafe ownership on homedir '/root/.gnupg'
> [GNUPG:] KEY_CONSIDERED 64DA0EF748DCFAB0D2661171005C84091F5630E0 2
> [GNUPG:] BEGIN_SIGNING H8
> [GNUPG:] PINENTRY_LAUNCHED 59 curses 1.3.1-unknown /dev/console xterm-256color :0 20620/1000/65534 0/0 0
> gpg: signing failed: Permission denied
> [GNUPG:] FAILURE sign 83918849
> gpg: signing failed: Permission denied
> 
> fatal: failed to write commit object
> ```
> 
> I don't know what its trying to access anyone with the
> experties know what going wrong? I have also tried with bind
> mounting /dev/console but when I do that the tty command
> becomes:
> ```
> localhost # tty
> not a tty
> ```
> And get:
> ```
> localhost # git commit -s -S -a -m "test"
> error: gpg failed to sign the data:
> gpg: WARNING: unsafe ownership on homedir '/root/.gnupg'
> [GNUPG:] KEY_CONSIDERED 64DA0EF748DCFAB0D2661171005C84091F5630E0 2
> [GNUPG:] BEGIN_SIGNING H8
> [GNUPG:] PINENTRY_LAUNCHED 60 curses 1.3.1-unknown not a tty xterm-256color :0 ? 0/0 0
> gpg: signing failed: No such file or directory
> [GNUPG:] FAILURE sign 83918929
> gpg: signing failed: No such file or directory
> 
> fatal: failed to write commit object
> ```
> I can see that the :0 is the $DISPLAY variable and after
> that its showing the UIDs?
> 
> So TLDR: I can't get pinentry to work.
> 
> More info:
> If I use the tty pinenctry regardless of /dev/console being
> bind mounted or not I get:
> ```
> localhost # git commit -s -S -a -m "test"
> error: gpg failed to sign the data:
> gpg: WARNING: unsafe ownership on homedir '/root/.gnupg'
> [GNUPG:] KEY_CONSIDERED 64DA0EF748DCFAB0D2661171005C84091F5630E0 2
> [GNUPG:] BEGIN_SIGNING H8
> [GNUPG:] PINENTRY_LAUNCHED 58 tty 1.3.1-unknown - xterm-256color :0 - 0/0 0
> gpg: signing failed: Operation cancelled
> [GNUPG:] FAILURE sign 83886179
> gpg: signing failed: Operation cancelled
> 
> fatal: failed to write commit object
> ```
> 
> The host's UID is 1000 and inside the container I'm
> 100000(root) surely thats messing with it but I don't know
> how ncurses works.
> 
> Permissions on /dev/console (that bubblwrap creates):
> ```
> localhost # ll /dev/console 
> crw--w---- 1 1000 nobody 136, 1 Aug 30 20:37 /dev/console
> ```
> Permissions of bind mounted /dev/console:
> ```
>  localhost # ll /dev/console 
> crw--w---- 1 nobody nobody 5, 1 Aug 29 21:45 /dev/console
> ```
Nevermind I was able to get it to work via https://ao.bloat.cat/exchange/stackoverflow.com/questions/51504367/gpg-agent-forwarding-inappropriate-ioctl-for-device#59170001
Need to add
```
use-agent 
pinentry-mode loopback
```
to gpg.conf and
```
allow-loopback-pinentry
```
to gpg-agent.conf

Sorry for the noise!