drm/panic: Better binary encoding in QR code

Browse source

The current encoding, is done by converting 13bits of input into 4
decimal digits, that are then encoded efficiently using the numeric
encoding of the QR code specification.
The Fido v2.2 specification [1] uses a similar approach for its
QR-initiated authentication. The only difference is that it converts
7 bytes (56bits) of input into 17 decimal digits. The benefit is that
the algorithm doesn't require to split input bytes into 13bits chunk,
and the ratio is a bit better.
This improvement was proposed by Jó Ágila Bitsch in [2].
drm_panic is still young, and the QR code feature is not widely used,
so it's still time to switch to a common algorithm, shared with a
widely used standard.
I also changed the name of the url parameter, from zl= to z=, so the
website can keep backward compatibility if needed.

[1] https://fidoalliance.org/specs/fido-v2.2-rd-20230321/fido-client-to-authenticator-protocol-v2.2-rd-20230321.html#hybrid-qr-initiated
[2] https://github.com/kdj0c/panic_report/issues/2

Signed-off-by: Jocelyn Falempe <jfalempe@redhat.com>
Acked-by: Maxime Ripard <mripard@kernel.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20250128165254.893204-1-jfalempe@redhat.com

...

This commit is contained in:

Jocelyn Falempe 2025-01-28 17:52:10 +01:00

parent 0590c94c35

commit dbed4a797e

2 changed files with 36 additions and 74 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

2

drivers/gpu/drm/drm_panic.c

View file

108

drivers/gpu/drm/drm_panic_qr.rs

View file