scd: Rework the handling of the displayed serial number.
* scd/app.c (app_new_register): Call app_munge_serialno for Yubikeys. (app_munge_serialno): Handle Yubikey serial numbers. (card_get_serialno): Remove special Yubikey treatment. Drop arg is_canonical. (app_get_serialno): Clear ERRNO on error. (card_get_dispserialno): New. Also change formatting of Yubikey and OpenPGP numbers to match those printed on the card. (app_get_dispserialno): New. * scd/app-openpgp.c (do_getattr): Use app_get_dispserialno. (yubikey_get_serialno): Remove. * scd/app-piv.c (get_dispserialno): Remove. (do_getattr): Use app_get_dispserialno.
This patch gets us back to a unique serial number for cards and
provides a stable serial number as printed for Yubikeys.
Because we use a slightly different serial number now for Yubikeys and
cards only supporting OpenPGP card we need to come up with another
change so that the version number of OpenPGP serial numbers are
ignored when comparing card serial numbers. This is so that existing
stub keys of gpg-agent will continue to work.
- GnuPG-bug-id: T5100
- Signed-off-by: Werner Koch <wk@gnupg.org>