Enable TLS certificate compression

[rucoder]

Proposal

In order to minimize network traffic during TLS handshake Certificate TLS compression can be enabled on both client and server side. It is defined in RFC 8879. As per 24.01.25 neither popular HTTP servers e.g. nginx nor Go TLS client support this feature out of the box. The issue is a placeholder to gather information

1. Open SSL supports is since 3.2 Alpha 1 https://openssl-library.org/post/2023-09-07-ossl32a1/
2. nginx ticket that tracks the feature request https://trac.nginx.org/nginx/ticket/2546
3. Golang issue https://github.com/golang/go/issues/42967

Some example implementations

1. https://github.com/getlantern/utls/pull/15

Status in Rust

1. rustls supports it already.

[shjala]

How much traffic is saved?

[rucoder]

How much traffic is saved?

depends on certificate chain size which may be very big in some cases