scd: Add an re-select mechanism to switch apps.
* scd/app-common.h (struct app_ctx_s): Add func ptr 'reselect'. * scd/app-piv.c (do_reselect): New. (app_select_piv): Move AID constant to file scope. * scd/app-openpgp.c (do_reselect): New. (app_select_openpgp): Move AID constant to file scope. * scd/app.c (apptype_from_name): New. (check_application_conflict): Check against all apps of the card. Always set current_apptype. (select_additional_application): New. (maybe_switch_app): New. (app_write_learn_status, app_readcert, app_readkey, app_getattr) (app_setattr, app_sign, app_auth, app_decipher, app_writecert) (app_writekey, app_genkey, app_change_pin, app_check_pin): Use it here. (app_do_with_keygrip): Force reselect on success. (app_new_register): Move setting of CURRENT_APPTYPE to ... (select_application): here so that it will be set to the requested card. * scd/command.c (open_card_with_request): Select additional application if possible.
Noet that we will likely need to rework this even more so to get well
defined semantics for card access.
- Signed-off-by: Werner Koch <wk@gnupg.org>