On Mon, Jun 17, 2019 at 09:19:41PM -0700, Lisa Matias wrote: > X509_NAME_ENTRY *nameEntry; > nameEntry = X509_NAME_ENTRY_create_by_NID (&nameEntry, nid, > derTagToVType (tag), buffer, bufferLength); > *nameEntry->value->flags = specifiedFlags;* Can you be a bit more explicit about why you need to do this? What flags do you intend to set and why? That said, you can use: ASN1_STRING *X509_NAME_ENTRY_get_data(const X509_NAME_ENTRY *ne); to get the ASN1_STRING holding the value, and since ASN1_STRINGs are not opaque types, you can just use: value->flags = ... asuming that's a sensible thing to do. You may however be straying into undocumented behaviour, and so it might be good to know whether perhaps there's a better way of getting the result you actually want. -- Viktor.