Is TLS handshake symmetric?

What is the TLS handshake?

Every HTTP request to a server is accompanied by a TLS handshake: first the server sends a hello message and then the client sends an application layer protocol (in this case, HTTP/1.1) in encrypted format.

The connection is established in three phases. The ClientHello message is sent by the client in the first phase, followed by the ServerHello message and the Certificate message.

In the second phase, the ClientHello is authenticated by the ServerHello and the two parties can exchange symmetric keys for the encryption of subsequent data. In the final phase, both parties agree on a security association between themselves that allows the transfer of data securely. The handshake is then complete and the server and client exchange the finished message.

The handshake is usually implemented in a library in C, Java, Perl, Python, PHP, etc. However, for the sake of simplicity, I'll describe it in terms of a simplified example of a HTTP request using the standard library in Node.js.

The server-side code. The server-side code is straightforward: the server responds with a 200 OK response to the ClientHello, indicating that the handshake has succeeded. Const options = ; const server = https.createServer(options, handler); server.on('upgrade', function() ); server.listen(80);

In the callback passed to the https.createServer method, a secure connection is established. The handler is set as the callback for the response event. It takes two arguments: the request object, and the response object.

The request object is an EventEmitter that emits requests for the server to send back to the client. For instance, to get the HTML source of a webpage, we could use this: https.get('www.google.com', (res) => );

The response object is an EventEmitter that emits the responses of the requests that are sent by the client. For instance, if we request a website, we might get an HTTP response in the form of HTML, but we can also get a response to a websocket request.

Let socket = new WebSocket('wss://echo.org'); socket.

How do I verify my TLS handshake?

I am trying to get my local webserver to use a specific TLS certificate and to only accept connections that have that certificate.

This has the unfortunate side effect of blocking all external connections. I also want the entire connection to be as close to zero overhead as possible.

I have looked at some answers like this: ? But I'm not able to figure out how to solve my problem. I have set up my server with a test cert to get an idea of how TLS handshake works. With the server running on my localhost, I start Chrome with --allow-file-access-from-files. When I open Chrome, I see a page that loads just fine, but the page shows a status bar with a progress bar that says the site wants to be connected securely, but it's connecting insecurely.

I expected this status bar to show "connected successfully" or similar. Then I tried checking to see if I could connect to the URL in my browser (Chrome is set to use the systemwide default web browser, and I don't need to set it up) and I am able to connect without a problem. I've written up a simple script that can check for TLS verification by making requests using curl and the test certificate. When I run this script, I get an error in response. And even though it does not have any errors, it returns with a status code of 405 Method Not Allowed.

How do I debug a TLS handshake? What should I check to see if a handshake has been successful? Update: I have found this: Verify Your TLS Certificate Chain, but I'm not exactly sure how to make that happen. Do I just add the certificate chain to the ciphers for the sslpreferserverciphers setting? You will be interested in the openssl sclient command line tool. It is useful when debugging a SSL connection. It is especially helpful for debugging self signed certificates.