On Fri, Jun 28, 2019 at 09:22:48PM +0000, Mark Richter wrote: > I've tried looking this up on the web, but there is no clear guidance on how to get around this. The documentation is a good place to start. https://www.openssl.org/docs/man1.1.1/man3/DH_set0_pqg.html If that's not it, look for other manpages that mention DH: https://www.openssl.org/docs/man1.1.1/man3/ In Postfix I have some macros that simulate 1.1.x interfaces for OpenSSL 1.0.2: https://github.com/vdukhovni/postfix/blob/master/postfix/src/tls/tls.h#L87-L117 these are by no means a complete list, but my advice is to do something similar, that is, switch to the 1.1.x APIs and define forward-compatibility macros for 1.0.2. -- Viktor.