TLS/SSL session resume on FTP transfer connection with OpenSSL

Question

I\'m open source developer implementing FTP client (WinSCP).

I\'m trying to resume TLS/SSL session from the FTP control socket on the transfer socket. Some FTP serve

Answer 1

You must specifically enable client session caching on your SSL_CTX object with:

SSL_CTX_set_session_cache_mode(ctx, SSL_SESS_CACHE_CLIENT);

You may also need to increase the default session cache timeout (the default is 300 seconds), using SSL_CTX_set_timeout().

(You must also be creating your SSL objects from the same SSL_CTX object).