MEDIUM: quic: send version negotiation packet on unknown version

If the client announced a QUIC version not supported by haproxy, emit a
Version Negotiation Packet, according to RFC9000 6. Version Negotiation.

This is required to be able to use the framework for QUIC interop
testing from https://github.com/marten-seemann/quic-interop-runner. The
simulator checks that the server is available by sending packets to
force the emission of a Version Negotiation Packet.
1 file changed