RFR: 8349910: Implement HTTP/3 for the HTTP Client API

[Artur Barashev]

On Fri, 18 Apr 2025 13:05:24 GMT, Daniel Fuchs <dfuchs at openjdk.org> wrote:

> Hi,
> 
> Please find here a PR for the implementation of JEP [JDK-8291976: HTTP/3 for the HTTP Client API](https://bugs.openjdk.org/browse/JDK-8291976).
> 
> The CSR can be viewed at [JDK-8350588: Implement HTTP/3 for the HTTP Client API](https://bugs.openjdk.org/browse/JDK-8350588)
> 
> This JEP proposes to enhance the HttpClient implementation to support HTTP/3.
> It adds a non-exposed / non-exported internal implementation of the QUIC protocol based on DatagramChannel and the SunJSSE SSLContext provider.

src/java.base/share/classes/sun/security/ssl/X509Authentication.java line 221:

> 219:                             chc.peerSupportedAuthorities.clone(),
> 220:                     engine);
> 221:             // TODO should we have a method that can take QuicTLSEngine?

Yes, I think we should have a method for `QuicTLSEngine` in `X509KeyManagerImpl`. In that new method we should use session's `peerSupportedSignAlgs` to construct algorithm constraints the same way we do it for `SSLSocketImpl` and for `SSLEngineImpl`. This is per TLSv1.3 RFC:
https://datatracker.ietf.org/doc/html/rfc8446#section-4.2.3

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PR Review Comment: https://git.openjdk.org/jdk/pull/24751#discussion_r2054448979