Making it possible to define parameters for Diffie–Hellman key exchange.

Motivation:

Improving security of SSL transactions that use DHE-based ciphers. For
instance, it should be possible to change key size.

Modifications:

Adding a new native operation on OpenSSL that makes it possible to add
to an SSL context a file that defines DH parameters.

Result:

One can now create his/her dhparam key file using the following command
line:
openssl dhparam -rand - 2048 > /etc/ssl/certs/dhparam.pem
For parameters to be taken int o account, in Java, one should then call:
SSLContext.setTmpDH(sslContext.context(), "/etc/ssl/certs/dhparam.pem")