I have following problem: I want to avoid the user to explicitly specify a https-proxy in his browser.

Let me explain:

For http, a transparent proxy can be interfaced via iptables DNAT, for example.

Same for https will not work, without certificates installed etc.

However, I only want some basic info about the https-session, like traffic volume or destination domain.

In case, there is an explicit https-proxy defined in the browser, I can get this info from the connect request, preceding the secure data exchange.

But I want to avoid this explicit declararion.

Most likely I will need some custom programming for this, but may be there is a specialist here to give some direction.