Prompt for user/root password : set keymap

[Prunk Dump <prunkdump@gmail.com>]

Hello debian-live team,

I would like to prompt for user/root password at startup of the live
system. I have made a script inspired by the given
/usr/share/doc/live-config/examples/hooks/passwd script. But I am face
of two problems :

-> I'am french and I can't find how to change the keymap at the initramfs stage.
-> The "read" command on initramfs does not support the "backspace"
key. So the user can't correct the input.

Can someone give me an idea to prompt for password after the
console-setup stage ?

Thanks.

Baptiste.