X509_CRL_digest
if (!X509_CRL_digest(x, digest, md, &n)) {
if (!X509_CRL_digest(x->crl, evpmd, digest, NULL)) {
if (!X509_CRL_digest(crl, EVP_sha1(), crl->sha1_hash, NULL))
int X509_CRL_digest(const X509_CRL *data, const EVP_MD *type,