cipher: Support internal hashing for DSA and ECDSA signing.
* cipher/dsa-common.c (_gcry_dsa_compute_hash): New. * cipher/pubkey-internal.h (_gcry_dsa_compute_hash): New. * cipher/dsa.c (verify): Add FLAGS and HASHALGO. (test_keys): Follow the change of verify API. (sign, verify): Support PUBKEY_FLAG_PREHASH flag to hash internally. (selftest_sign): Test with "prehash" flag. * cipher/ecc-common.h (_gcry_ecc_ecdsa_verify): Add FLAGS and HASHALGO. * cipher/ecc-ecdsa.c (_gcry_ecc_ecdsa_sign): Support PUBKEY_FLAG_PREHASH flag to hash internally. (_gcry_ecc_ecdsa_verify): Likewise. * cipher/ecc.c (test_keys): Follow the change of _gcry_ecc_ecdsa_verify API. (selftest_sign): Test with "prehash" flag. * cipher/pubkey-util.c (_gcry_pk_util_data_to_mpi): Support handling of "hash-algo" and "value" with "prehash" flag.
- GnuPG-bug-id: T5530
- Signed-off-by: NIIBE Yutaka <gniibe@fsij.org>