How to choose server certificate dynamically and in `aync` manner based on hostname in ClientHello?

help
1

Hello Rust Community!

I am new to async Rust and have moderate experience of writing sync code in Rust. I am writing a TCP server with TLS support for learning purpose. I want to choose certificates based on the hostname specified in ClientHello. Certificates will be fetched from other key store making it perfect usecase for async. I have read several options, but none provides a concrete example on how to do it.

  1. I came to know about cert_resolver in rustls::server::ServerConfig. But from my understanding it is not async, and as mentioned in rustls documentation:

For applications that use async I/O and need to do I/O to choose a certificate (for instance, fetching a certificate from a data store), the Acceptor interface is more suitable.

Ok, good.But if I go to Acceptor documentaion, I go blank on how to use it with async runtime like tokio? I could not get clear idea of how to use this struct when working with tokio as tokio_rustls::TlsAcceptor does not have similar methods like read_tls in rustls.

  1. I also referred to alternatives like tokio_native_tls. But again same issue, not a single example available or I could not find it.

What is recommended way of achieving this functionality when using tokio? An minimal example is very much appreciated.

Thank you!