scd: Add --challenge-response option to PK_AUTH for OpenPGP card.
* scd/app-openpgp.c (rmd160_prefix, sha1_prefix, sha224_prefix) (sha256_prefix, sha384_prefix, sha512_prefix): Move the scope up. (gen_challenge): New. (do_auth): Support challenge-response check if it signs correctly. * scd/app.c (app_auth): Remove the check INDATA and INDATALEN. * scd/command.c (cmd_pkauth): Support --challenge-response option.
- GnuPG-bug-id: T5862
- Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>