Illegal SNI hostname received [49, 48, 46, 48, 46, 48, 46, 52]

[huguesBouvier]

I am getting Illegal SNI hostname received [49, 48, 46, 48, 46, 48, 46, 52] when hooking up a server to a legacy system.

This is my configuration:

let tls_cfg = {
    // Load public certificate.
    let server_cert = X509::stack_from_pem(server_cert.as_bytes()).unwrap();

    let mut server_certs: Vec<Certificate> = Vec::new();
    for x509 in server_cert {
        let certificate = tokio_rustls::rustls::Certificate(x509.to_der().unwrap());
        server_certs.push(certificate);
    } 

    // Load private key.
    let server_key = pem_parser::pem_to_der(server_key);
    let server_key = tokio_rustls::rustls::PrivateKey(server_key);                
    // Do not use client certificate authentication.
    let mut cfg = ServerConfig::builder()
        .with_safe_defaults()
        .with_no_client_auth()
        .with_single_cert(server_certs, server_key)
        .unwrap();

    // Configure ALPN to accept HTTP/2, HTTP/1.1 in that order.
    //cfg.alpn_protocols = vec![b"h2".to_vec(), b"http/1.1".to_vec()];
    sync::Arc::new(cfg)
};
let acceptor = tokio_rustls::TlsAcceptor::from(tls_cfg);
let client_stream = acceptor.accept_with(client_stream, session).await.unwrap();

Is there a way to ignore that illegal SNI message since I cannot change the code the generates it?

[djc]

This should probably be filed against rustls, not tokio-rustls.

There is no way to ignore an illegal message. The hostname you posted is actually an IP address (10.0.0.4), which rustls doesn't support yet.