Keyboard backspace behavior at boot-time decryption passphrase

SporadicThought · 02-06-2021, 11:42 PM

Quote:

OS: Kali Linux 2020.4
System: Acer Predator 17 (G9-791) w/ German keyboard.

** firmware-linux_20201218-3_all.deb (Debian Sid [testing]) installed

Encrypted layout:
LVM on LUKS2: / /home swap
Non-encrypted: /boot /boot/efi

At the passphrase prompt, the backspace key adds a masked character to the passphrase entry box. Behavior should be deletion of previous character.

My attempted solution:

Default boot into Kali

Code:

# dpkg-reconfigure keyboard-configuration

.

Code:

Generic 105-key PC (intl.)
English (US) - English (US, euro on 5)
AltGr: Default for the keyboard layout
Compose: No compose key
Ctl+Atl+Backspace to terminate X = Yes

On reboot, backspace behavior is as initially described.

Afterward:

Code:

sudo nano /etc/initramfs-tools/initramfs.conf

,

modify,
Code:
```
KEYMAP=n
```
,
to,
Code:
```
KEYMAP=y
```
.
Code:
```
$ sudo update-initramfs -uv
```
.
On reboot, backspace behavior is as initially described.

The backspace works as it should once the OS is operational.

Tips or suggestions on solving or troubleshooting the issue are appreciated.

ondoho · 02-07-2021, 01:35 AM

What key are you talking about.
After booting into GUI, launch

Code:

xev

and use the key in question - what does it say?

Are you sure the intiramfs takes over keyboard settings from dpkg-reconfigure? I think the console keymap mentioned in its man page is something else?

SporadicThought · 02-07-2021, 03:30 AM

Quote:

Originally Posted by ondoho

What key are you talking about.
After booting into GUI, launch

Code:

xev

and use the key in question - what does it say?

Code:

$ xev

KeyRelease event, serial 37, synthetic NO, window 0x5a00001,
    root 0x944, subw 0x0, time 1834238, (64,-12), root:(927,591),
    state 0x10, keycode 22 (keysym 0xff08, BackSpace), same_screen YES,
    XLookupString gives 1 bytes: (08) "
    XFilterEvent returns: False

Quote:

Are you sure the intiramfs takes over keyboard settings from dpkg-reconfigure? I think the console keymap mentioned in its man page is something else?

It didn't occur to me to look in the man for initramfs or keyboard-configuration. I will give that a try.

I'm hoping someone with applied experience will save me from making a mistake.

Thank you for the hint!

ondoho · 02-09-2021, 12:44 PM

OK, so it really is the backspace key.
Sorry, I had to make sure, maybe not everybody knows the difference between Backspace and Delete key.
I have never heard of a keyboard layout that uses this key differently.
Is everything else working normally? You can still enter that passphrase and start the system?
Is that a graphical password entering thingy, or console?
If you don't go to graphical login, but TUI only (console, tty etc.), or maybe recovery - does it show the same behaviour?