Files
mc-proxy/PROGRESS.md
Kyle Isom 97909b7fbc Add L7 TLS-terminating HTTP/2 reverse proxy
New internal/l7 package implements TLS termination and HTTP/2 reverse
proxying for L7 routes. The proxy terminates the client TLS connection
using per-route certificates, then forwards HTTP/2 traffic to backends
over h2c (plaintext HTTP/2) or h2 (re-encrypted TLS).

PrefixConn replays the peeked ClientHello bytes into crypto/tls.Server
so the TLS handshake sees the complete ClientHello despite SNI
extraction having already read it.

Serve() is the L7 entry point: TLS handshake with route certificate,
ALPN negotiation (h2 preferred, HTTP/1.1 fallback), then HTTP reverse
proxy via httputil.ReverseProxy. Backend transport uses h2c by default
(AllowHTTP + plain TCP dial) or h2-over-TLS when backend_tls is set.

Forwarding headers (X-Forwarded-For, X-Forwarded-Proto, X-Real-IP)
are injected from the real client IP in the Rewrite function. PROXY
protocol v2 is sent to backends when send_proxy_protocol is enabled,
using the request context to carry the client address through the
HTTP/2 transport's dial function.

Server integration: handleConn dispatches to handleL7 when route.Mode
is "l7". The L7 handler converts RouteInfo to l7.RouteConfig and
delegates to l7.Serve.

L7 package tests: PrefixConn (4 tests), h2c backend round-trip,
forwarding header injection, backend unreachable (502), multiple
HTTP/2 requests over one connection.

Server integration tests: L7 route through full server pipeline with
TLS client, mixed L4+L7 routes on the same listener verifying both
paths work independently.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
2026-03-25 13:43:20 -07:00

2.9 KiB

PROGRESS.md

Tracks implementation status against PROJECT_PLAN.md. Updated as work proceeds. Each item is marked:

  • [ ] not started
  • [~] in progress
  • [x] complete
  • [—] skipped (with reason)

Phase 1: Database & Config Foundation

  • 1.1 Config struct updates (Listener.ProxyProtocol, Route.Mode/TLSCert/TLSKey/BackendTLS/SendProxyProtocol)
  • 1.2 Config validation updates (L7 requires cert/key, mode enum, cert/key pair loading)
  • 1.3 Database migration v2 (new columns on listeners and routes)
  • 1.4 DB struct and CRUD updates (new fields in Listener, Route, all queries)
  • 1.5 Server data loading (RouteInfo struct replaces bare backend string in route lookup)
  • 1.6 Tests (config, DB migration, CRUD, server unchanged)

Phase 2: PROXY Protocol

  • 2.1 internal/proxyproto/ package (v1/v2 parser, v2 writer)
  • 2.2 Server integration — receive (parse PROXY header before firewall on enabled listeners)
  • 2.3 Server integration — send on L4 (write PROXY v2 header before ClientHello on enabled routes)
  • 2.4 Tests (receive, send, firewall uses real IP, malformed header rejection)

Phase 3: L7 Proxying

  • 3.1 internal/l7/ package (PrefixConn, HTTP/2 reverse proxy with h2c, Serve entry point)
  • 3.2 Server integration (dispatch to L4 or L7 based on route.Mode in handleConn)
  • 3.3 PROXY protocol sending in L7 path
  • 3.4 Tests (TLS termination, h2c backend, re-encrypt, mixed L4/L7 listener, gRPC through L7)

Phase 4: gRPC API & CLI Updates

  • 4.1 Proto updates (new fields on Route, AddRouteRequest, ListenerStatus)
  • 4.2 gRPC server updates (accept/validate/persist new route fields)
  • 4.3 Client package updates (new fields on Route, ListenerStatus)
  • 4.4 mcproxyctl updates (flags for routes add, display in routes list)
  • 4.5 Tests (gRPC round-trip with new fields, backward compatibility)

Phase 5: Integration & Polish

  • 5.1 Dev config update (srv/mc-proxy.toml with L7 routes, test certs)
  • 5.2 Multi-hop integration test (edge→origin via PROXY protocol)
  • 5.3 gRPC-through-L7 validation (unary, streaming, trailers, deadlines)
  • 5.4 Web UI through L7 validation (HTTP/1.1, HTTP/2, static assets)
  • 5.5 Documentation (verify ARCHITECTURE.md, CLAUDE.md, Makefile)

Current State

The codebase is L4-only. All existing functionality is working and tested:

  • SNI extraction and raw TCP relay
  • Global firewall (IP, CIDR, GeoIP country blocking, per-IP rate limiting)
  • SQLite persistence with write-through pattern
  • gRPC admin API (Unix socket) for route and firewall CRUD
  • CLI tools (mc-proxy server/status/snapshot, mcproxyctl)
  • make all passes (vet, lint, test, build)

ARCHITECTURE.md and CLAUDE.md have been updated to describe the target state. PROJECT_PLAN.md describes the implementation path. This file tracks progress.