examples

Rustls Examples

This directory contains a number of examples that use Rustls.

We recommend new users start by looking at simpleclient.rs and simpleserver.rs. Once those are understood, tlsclient-mio.rs and tlsserver-mio.rs provide more advanced examples.

Client examples

• simpleclient.rs - shows a simple client configuration that uses sensible defaults. It demonstrates using the Stream helper to treat a Rustls connection as you would a bi-directional TCP stream.
• tlsclient-mio.rs - shows a more complete client example that handles command line flags for customizing TLS options, and uses MIO to handle asynchronous I/O.
• limitedclient.rs - shows how to configure Rustls so that unused cryptography is discarded by the linker. This client only supports TLS 1.3 and a single cipher suite.
• simple_0rtt_client.rs - shows how to make a TLS 1.3 client connection that sends early 0RTT data.
• unbuffered-client.rs - shows an advanced example of using Rustls lower-level APIs to implement a client that does not buffer any data inside Rustls.
• unbuffered-async-client.rs - shows an advanced example of using Rustls lower-level APIs to implement a client that does not buffer any data inside Rustls, and that processes TLS events asynchronously.
• ech-client.rs - shows how to configure Rustls to use encrypted client hello (ECH), including fetching an ECH config list with DNS-over-HTTPS.

Server examples

• simpleserver.rs - shows a very minimal server example that accepts a single TLS connection. See tlsserver-mio.rs or server_acceptor.rs for a more realistic example.
• tlsserver-mio.rs - shows a more complete server example that handles command line flags for customizing TLS options, and uses MIO to handle asynchronous I/O.
• simple_0rtt_server.rs - shows how to make a TLS1.3 that accepts multiple connections and prints early 0RTT data.
• server_acceptor.rs - shows how to use the Acceptor API to create a server that generates a unique ServerConfig for each client. This example also shows how to use client authentication, CRL revocation checking, and uses rcgen to generate its own certificates.
• unbuffered-server.rs - shows an advanced example of using Rustls lower-level APIs to implement a server that does not buffer any data inside Rustls.

Client-Server examples

• A client-server example using Raw Public Keys (RFC 7250) can be found in raw_key_openssl_interop.