A HTTP proxy server that only correctly handles the `CONNECT` verb, kind of. It
create a TLS with a valid certificate signed by a generated CA certificate and
returns `HTTP/1.1 200 OK`.

This is just a project to get familiar with the OpenSSL library, the HTTP proxy
tunnelling protocol and on-the-fly certificate generation. It is not intended
to be a useful proxy server.

    // create ca key, password=password
    openssl genrsa -des3 -out ca.key 2048

    // create ca pem, defaults should be ok
    openssl req -x509 -new -nodes -key ca.key -sha256 -days 1024 -out ca.pem

    // build the server
    make

    // run the server
    ./server

    // test the server
    curl https://any.server.it.does.not.matter --cacert ca.pem --proxy localhost:4433