X509_find_by_subject
return X509_find_by_subject(certs, id->value.byName);
signer = X509_find_by_subject(req->optionalSignature->certs, nm);
if ((signer = X509_find_by_subject(certs, nm)) != NULL) {
X509 *X509_find_by_subject(STACK_OF(X509) *sk, const X509_NAME *name);