* cipher/md.c (prepare_macpads): Reject < 112-bit key.
* cipher/kdf.c (selftest_pbkdf2): Remove selftest cases with shorter
key.
* cipher/mac-hmac.c (selftests_sha224, selftests_sha256): Likewise.
(selftests_sha384, selftests_sha512, selftests_sha3): Likewise.
* tests/basic.c (check_one_hmac) Handle an error when shorter key
is rejected.
(check_one_mac): Likewise.
* tests/t-kdf.c (check_pbkdf2, check_scrypt): Likewise.