OSSL_PKEY_PARAM_RSA_DIGEST
const char *key_md = OSSL_PKEY_PARAM_RSA_DIGEST;
param_md = OSSL_PARAM_locate_const(params, OSSL_PKEY_PARAM_RSA_DIGEST);
OSSL_PKEY_PARAM_RSA_DIGEST, mdname,
OSSL_PARAM_utf8_string(OSSL_PKEY_PARAM_RSA_DIGEST, NULL, 0), \