tree ed779f259c0d24f5db3f8de0f221197637f13171
parent 1fdac9bdbf85d27537e8ce47ca4f1eaa034f1ff5
author danzh <danzh@google.com> 1675105126 -0800
committer Copybara-Service <copybara-worker@google.com> 1675105172 -0800

Implement QUIC server preferred address (SPA) on server side. Basically advertising SPA and handling clients migrating to using SPA.

Current implementation is a half-way SPA which advertises SPA in transport parameters and accepts packets received on SPA, but the server doesn't validate the migration nor does it switch to use SPA to send packets(go/quic_server_migration).

The behavior is behind config knobs QuicConfig::SetIPv(4|6)AlternateServerAddressToSend().

PiperOrigin-RevId: 505741961