feat(multiplayer): bound control-plane websocket traffic

multiplayer-next.md

@@ -1191,7 +1191,7 @@ the local/CI/community transport, not a silent production fallback.
 | 8.9 `[D:8.4,8.7]` | **IN PROGRESS.** Pure Go join policy binds SteamID/player/match/server/team/slot/protocol/expiry, rejects duplicate roster slots, permits same-identity reclaim through backend loss and fences prior server-owned generations | `server/domain/reconnect.go` covers SteamID/server/slot binding, expiry, repeated reclaim, grace boundary and old-generation fencing; signed token issuance/verification, persistent leases, Godot `hello` transport and production integration remain |
 | 8.10 `[D:8.5,8.31]` | **IN PROGRESS.** Dependency-free workload credential policy validates an adapter-verified signature, issuer/audience/time bounds, namespace/service account, pod UID, GameServer UID, allocation ID, match ID and server ID before result submission; `server/workload` now parses projected compact JWTs, rejects unsigned/malformed/ambiguous tokens, verifies signing input through an injected trust callback, and delegates exact binding to the domain policy; the API exposes the workload-authenticated server result route. **`WorkloadVerify` is now wired for real** -- the blocker this row previously named (`cmd/control-plane/main.go` never wiring it, so `/register` and `/result` 503'd on every real request) is closed by taking a different, equally-valid approach instead of the Kubernetes-JWT one: `serverMutation` only ever compares `WorkloadBinding.ServerID`/`.MatchID` (and `AdvanceServerRegistration` only additionally needs `.AllocationID`) -- nothing downstream requires Namespace/ServiceAcct/PodUID/GameServerUID, so a Kubernetes-issued token was never actually required, just the assumption that it was. `server/workload/signed_token.go` mints and verifies a short-lived HMAC-signed token with a secret only the control plane holds (the same trust model `domain.SessionStore` already uses for player sessions), needing no cluster JWKS/TokenReview to validate -- signature and expiry are fully self-contained. The token binds only `allocation_id` (deliberately, not `match_id`/`server_id` too: it must be requestable in the same Agones request that asks for a server, before Agones has picked one) -- `store.AllocationBindingByAllocationID` resolves `match_id`/`server_id` durably from the `allocations` table at verify time, so a token can never claim a pairing that wasn't actually, durably allocated. `api.WorkloadVerifierFromSignedToken` combines both and is wired into `cmd/control-plane` (`--workload-secret`/`COSMIC_CLASH_WORKLOAD_SECRET`; a startup warning fires and the route stays 503 if it's left unset) and `cmd/testkit-api` (fixed test secret). **The delivery channel is now wired too**: `agones.Client` gains `WorkloadSecret`/`WorkloadTokenTTL` -- when set, `Allocate` mints a token for the allocation and requests it as a third `cosmic-clash.io/workload-token` annotation alongside match-id/allocation-id, wired from `cmd/allocator`'s own `--workload-secret`/`COSMIC_CLASH_WORKLOAD_SECRET` (must match the control plane's); `supervisor.Supervisor.workloadToken()` resolves the bearer credential with an explicit `--workload-token-path` (kept for a possible future Kubernetes-JWT path) always winning, otherwise falling back to that same annotation -- the same fallback pattern `matchID()` already used for `cosmic-clash.io/match-id`. `WorkloadTokenPath` is accordingly no longer required at construction time | `server/domain/workload.go`, `server/workload/jwt.go`, `server/api/service.go` and adversarial tests reject every binding mutation, missing/unverified signature, `none`/malformed JWT, ambiguous audience, server/match mismatch and time boundary; `server/testkit/pipeline_test.go` carries allocation identity through the offline result path; `cmd/control-plane` now wires `ResultSubmitter: store.PostgresResults{DB: db}` (a ready-made adapter that had been referenced from nowhere at all, not even a test); `server/workload/signed_token_test.go` covers round-trip, tampered payload, wrong secret, malformed input and the exact expiry boundary; `server/api/workload_verifier_integration_test.go` (opt-in, real PostgreSQL) covers acceptance against a real allocation row, rejection of an unrecorded allocation, that two distinct real allocations each resolve to their own and only their own match/server pairing, and the previously-503 `Service.WorkloadVerify` field itself now succeeding -- all verified clean with `-race` across multiple runs; `cmd/control-plane/main_test.go`'s `TestServerRoutesRequireWorkloadVerifyToBeWired` now documents and pins the misconfigured-secret case specifically, not the "always unwired" case; `server/agones/allocation_test.go`'s `TestAllocateRequestsAWorkloadTokenAnnotationWhenConfigured` and `server/supervisor/supervisor_test.go`'s new annotation-fallback/fails-closed pair cover the delivery channel end to end (mint -> annotation -> supervisor read -> Authorization header) short of a live cluster. **What's still missing**: this has never run against a real Agones cluster (only HTTP-level fakes), so the exact `object_meta` JSON casing Agones actually returns remains unverified from this sandbox (see `GameServer.ObjectMeta`'s existing caveat); live duplicate/conflict alerting also remains |
 | 8.11 `[D:8.1]` | **DONE.** Write the threat model: forged clients/replay/queues/results, floods/bots, pod/insider compromise, gameplay and API DDoS, SDR signing-key theft, dependencies and denial-of-wallet | [`docs/THREAT-MODEL.md`](docs/THREAT-MODEL.md) records prevention, detection/response, owner and residual risk for every threat; it separates offline CA/online signer, client/game-server/PostgreSQL/Redis trust boundaries and recovery behavior |
-| 8.12 `[D:8.11]` | **IN PROGRESS.** Provider-neutral Kubernetes baseline enforces restricted namespace admission, non-root/read-only/no-capability workloads, separate service accounts, default-deny networking and explicit edge/data/DNS/Agones/metrics flows; application manifests consume externally populated Secret objects; the Go API and allocator now have bounded per-replica account+IP rate/quota boundaries and metrics endpoints, plus an atomic operator-controlled degraded-mode gate that sheds new login/queue/proposal work while preserving live-match paths | `deploy/k8s/base/` includes hardened control-plane, allocator, and game-server resources; the control-plane now has health probes, a disruption budget, explicit zero-unavailable/one-surge rolling updates with graceful termination, failure-domain spreading/anti-affinity, and Secret-backed `COSMIC_CLASH_POSTGRES_DSN`/`COSMIC_CLASH_WORKLOAD_SECRET` runtime wiring; `server/security/test_kubernetes_policies.py`, `server/api/rate_limit.go`, `server/api/admission.go`, allocator metrics tests and adversarial checks cover static hardening, secret-reference invariants, fixed-window limits, bounded labels/key memory, atomic account+IP charging, route classification, concurrent toggling and degraded responses; production `cmd/control-plane` now wires the bounded limiter by default with `--rate-limit`, `--rate-limit-window`, and `--rate-limit-max-keys`, and the base Deployment declares those defaults explicitly; start with control-plane `--degraded`, enable with SIGUSR1, disable with SIGUSR2; private-store provisioning, distributed/global quotas, edge DDoS/WAF/origin shielding, WebSocket limits, encrypted backups and live policy/load tests remain |
+| 8.12 `[D:8.11]` | **IN PROGRESS.** Provider-neutral Kubernetes baseline enforces restricted namespace admission, non-root/read-only/no-capability workloads, separate service accounts, default-deny networking and explicit edge/data/DNS/Agones/metrics flows; application manifests consume externally populated Secret objects; the Go API and allocator now have bounded per-replica account+IP rate/quota boundaries and metrics endpoints, plus an atomic operator-controlled degraded-mode gate that sheds new login/queue/proposal work while preserving live-match paths | `deploy/k8s/base/` includes hardened control-plane, allocator, and game-server resources; the control-plane now has health probes, a disruption budget, explicit zero-unavailable/one-surge rolling updates with graceful termination, failure-domain spreading/anti-affinity, and Secret-backed `COSMIC_CLASH_POSTGRES_DSN`/`COSMIC_CLASH_WORKLOAD_SECRET` runtime wiring; the authenticated WebSocket now requires RFC 6455 version 13, enforces a bounded 64 KiB frame size, two-minute idle deadline, 120-message/minute inbound budget, and bounded per-player fan-out; `server/security/test_kubernetes_policies.py`, `server/api/rate_limit.go`, `server/api/admission.go`, allocator metrics tests and adversarial checks cover static hardening, secret-reference invariants, fixed-window limits, bounded labels/key memory, atomic account+IP charging, route classification, concurrent toggling and degraded responses; production `cmd/control-plane` now wires the bounded limiter by default with `--rate-limit`, `--rate-limit-window`, and `--rate-limit-max-keys`, and the base Deployment declares those defaults explicitly; start with control-plane `--degraded`, enable with SIGUSR1, disable with SIGUSR2; private-store provisioning, distributed/global quotas, edge DDoS/WAF/origin shielding, encrypted backups and live policy/load tests remain |
 | 8.13 `[D:8.12]` | **IN PROGRESS.** Docker/Kubernetes references are digest-pinned, a dependency-free checker rejects mutable tags/plaintext credentials and concrete release overlays can reject template digests; release documentation defines SBOM, dependency/image scanning, signing, admission verification and a 24-hour critical-fix SLA | `scripts/verify_supply_chain.py`, `server/security/test_supply_chain.py`, `docs/SUPPLY-CHAIN.md` and `.github/workflows/supply-chain.yml` cover repository policy and provenance requirements; registry SBOM/scan/sign/admission execution and a concrete production overlay remain |
 
 #### 8C — Queueing, matchmaking, playlists and rating

server/api/events.go

@@ -19,9 +19,12 @@ import (
 )
 
 const (
-	webSocketGUID      = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"
-	maxWebSocketFrame  = 64 << 10
-	eventQueueCapacity = 32
+	webSocketGUID          = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11"
+	maxWebSocketFrame      = 64 << 10
+	eventQueueCapacity     = 32
+	webSocketIdleLimit     = 2 * time.Minute
+	webSocketMessageLimit  = 120
+	webSocketMessageWindow = time.Minute
 )
 
 // ControlPlaneEvent is the server-to-client envelope defined by the v1
@@ -139,7 +142,7 @@ func (s *Service) controlPlaneEvent(w http.ResponseWriter, r *http.Request) {
 		writeError(w, http.StatusMethodNotAllowed, "method_not_allowed")
 		return
 	}
-	if !isWebSocketUpgrade(r) || !validWebSocketKey(r.Header.Get("Sec-WebSocket-Key")) {
+	if !isWebSocketUpgrade(r) || r.Header.Get("Sec-WebSocket-Version") != "13" || !validWebSocketKey(r.Header.Get("Sec-WebSocket-Key")) {
 		writeError(w, http.StatusBadRequest, "invalid_websocket_upgrade")
 		return
 	}
@@ -250,11 +253,20 @@ func validWebSocketKey(key string) bool {
 
 func readWebSocketFrames(connection net.Conn, writeMu *sync.Mutex) {
 	reader := bufio.NewReader(connection)
+	windowStarted := time.Now()
+	messageCount := 0
 	for {
+		if err := connection.SetReadDeadline(time.Now().Add(webSocketIdleLimit)); err != nil {
+			return
+		}
 		opcode, _, err := readWebSocketFrame(reader)
 		if err != nil || opcode == 0x8 {
 			return
 		}
+		now := time.Now()
+		if !allowWebSocketMessage(now, &windowStarted, &messageCount) {
+			return
+		}
 		if opcode == 0x9 {
 			writeMu.Lock()
 			_ = writeWebSocketFrame(connection, 0xA, nil)
@@ -263,6 +275,21 @@ func readWebSocketFrames(connection net.Conn, writeMu *sync.Mutex) {
 	}
 }
 
+func allowWebSocketMessage(now time.Time, windowStarted *time.Time, count *int) bool {
+	if windowStarted == nil || count == nil || now.IsZero() {
+		return false
+	}
+	if !now.Before(windowStarted.Add(webSocketMessageWindow)) {
+		*windowStarted = now
+		*count = 0
+	}
+	if *count >= webSocketMessageLimit {
+		return false
+	}
+	*count++
+	return true
+}
+
 func readWebSocketFrame(reader *bufio.Reader) (byte, []byte, error) {
 	first, err := reader.ReadByte()
 	if err != nil {

server/api/events_test.go

@@ -0,0 +1,39 @@
+package api
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+)
+
+func TestWebSocketHandshakeRequiresRFC6455Version(t *testing.T) {
+	service := &Service{}
+	request := httptest.NewRequest(http.MethodGet, "/v1/events", nil)
+	request.Header.Set("Upgrade", "websocket")
+	request.Header.Set("Connection", "Upgrade")
+	request.Header.Set("Sec-WebSocket-Version", "12")
+	request.Header.Set("Sec-WebSocket-Key", "dGhlIHNhbXBsZSBub25jZQ==")
+	recorder := httptest.NewRecorder()
+	service.controlPlaneEvent(recorder, request)
+	if recorder.Code != http.StatusBadRequest {
+		t.Fatalf("version 12 status = %d, want 400", recorder.Code)
+	}
+}
+
+func TestWebSocketMessageBudgetIsBoundedAndResets(t *testing.T) {
+	start := time.Unix(1000, 0)
+	window := start
+	count := 0
+	for i := 0; i < webSocketMessageLimit; i++ {
+		if !allowWebSocketMessage(start, &window, &count) {
+			t.Fatalf("message %d was rejected within the budget", i)
+		}
+	}
+	if allowWebSocketMessage(start, &window, &count) {
+		t.Fatal("message over the WebSocket budget was accepted")
+	}
+	if !allowWebSocketMessage(start.Add(webSocketMessageWindow), &window, &count) {
+		t.Fatal("WebSocket message budget did not reset")
+	}
+}