This commit implements comprehensive dual-stack support for the proxy,
allowing it to listen on both IPv4 and IPv6 addresses simultaneously.
Key changes:
- Added new dual_stack.rs module with DualStackTcpListener implementation
- Updated SSH module to use dual-stack listener
- Updated configuration documentation to reflect IPv6 support
- Added comprehensive tests for dual-stack functionality
The implementation is inspired by tokio_dual_stack but implemented
natively without external dependencies. It provides fair connection
distribution between IPv4 and IPv6 clients while maintaining full
backward compatibility with existing IPv4-only configurations.
Signed-off-by: Sienna Meridian Satterwhite <sienna@sunbeam.pt>
Root cause: upstream_request_filter was inserting x-forwarded-proto with
a raw headers.insert() call (via DerefMut) which only updates base.headers
but NOT the CaseMap. header_to_h1_wire zips CaseMap with base.headers, so
headers added without a CaseMap entry are silently dropped on the wire.
Fix: use insert_header() which keeps both maps in sync.
Also adds:
- src/lib.rs + [lib] section: exposes SunbeamProxy/RouteConfig/AcmeRoutes
to integration tests without re-declaring modules in main.rs
- tests/e2e.rs: real end-to-end test — starts a SunbeamProxy over plain
HTTP, routes it to a TCP echo backend, and asserts x-forwarded-proto: http
is present in the upstream request headers
- Updated unit tests to verify header_to_h1_wire round-trip (not just that
HeaderMap::insert works in isolation)
Signed-off-by: Sienna Meridian Satterwhite <sienna@sunbeam.pt>
