search for: ssl_min_proto_version

...linear version approach: the application may request a minimum and a maximum allowed version (inclusive), allowing all versions inbetween as well. Dovecot's existing ssl_protocols option is probably not ideal to use with this new "linear" model. Instead, I introduced two new options, ssl_min_proto_version and ssl_max_proto_version, that map directly to OpenSSL 1.1 concepts. I have tested the patch with both OpenSSL 1.0 and OpenSSL 1.1. With OpenSSL 1.1 it works as expected; with OpenSSL 1.0 it doesn't seem to break anything. Other than that, this is a first version; I'm sure there are still...