Hi, I have a problem with porting OpenSSL code from 1.0 to 1.1. Please do not complain that it does not look like it make sense what this code does here - complain to Microsoft who implements certs with RDP non-standard ... The goal of the following code is to change the ASN.1 value of the signature algorithm in a certificate. // OpenSSL 1.0 code, well, really written already when 0.9 was there nid = OBJ_obj2nid(cert->cert_info->key->algor->algorithm); if ((nid == NID_md5WithRSAEncryption) || (nid == NID_shaWithRSAEncryption)) { ASN1_OBJECT_free(cert->cert_info->key->algor->algorithm); cert->cert_info->key->algor->algorithm = OBJ_nid2obj(NID_rsaEncryption); } // OpenSSL 1.1 code nid = X509_get_signature_nid(cert); if ((nid == NID_md5WithRSAEncryption) || (nid == NID_shaWithRSAEncryption)) { ... how to set the algorithm in the cert to NID_rsaEncryption in OpenSSL v1.1.x? Any help how to implement this with the new 1.1 functions is highly appreciated :) Greets, Marc -- Marc Heuse www.mh-sec.de PGP: AF3D 1D4C D810 F0BB 977D 3807 C7EE D0A0 6BE9 F573