Introduce reusable `inbound_mtls_profiles` in root config and support
`entrypoint.inbound_mtls_profile` to require client certificates for all
HTTPS traffic on an entrypoint. Profiles can trust the system CA store,
custom PEM CA files, or both, and are compiled into TLS client-auth
pools during entrypoint initialization.
Also add route-scoped `inbound_mtls_profile` support for HTTP-based
routes when no global entrypoint profile is configured. Route-level mTLS
selection is driven by TLS SNI, preserves existing behavior for open and
unmatched hosts, and returns the intended 421 response when secure
requests omit SNI or when Host and SNI resolve to different routes.
Add validation for missing profile references and unsupported non-HTTP
route usage, update config and route documentation/examples, expand
inbound mTLS handshake and routing regression coverage, and bump
`goutils` for HTTPS listener test support.
Add `relay_proxy_protocol_header` configuration option for TCP routes that enables
forwarding the original client IP address to upstream services via PROXY protocol
v2 headers. This feature is only available for TCP routes and includes validation
to prevent misuse on UDP routes.
- Add RelayProxyProtocolHeader field to Route struct with JSON tag
- Implement writeProxyProtocolHeader in stream package to craft v2 headers
- Update TCPTCPStream to conditionally send PROXY header to upstream
- Add validation ensuring feature is TCP-only
- Include tests for both enabled/disabled states and incoming proxy header relay