feat(ops): protect metrics, rate-limit auth, agent secret timing, e2e smoke

Bearer для /metrics (EVOBGP_METRICS_TOKEN); rate limit /v1/auth/config; constant-time agent secret; OTel stub; Playwright smoke; HTTP_PROXY note; checklist обновлён.

Co-authored-by: Cursor <[email protected]>

internal/httpapi/ratelimit.go

@@ -0,0 +1,68 @@
+package httpapi
+
+import (
+	"net/http"
+	"os"
+	"strconv"
+	"strings"
+	"sync"
+	"time"
+)
+
+// authRateLimiter is a simple per-IP token bucket for public auth-ish endpoints.
+type authRateLimiter struct {
+	mu     sync.Mutex
+	hits   map[string][]time.Time
+	limit  int
+	window time.Duration
+}
+
+func newAuthRateLimiter() *authRateLimiter {
+	limit := 60
+	if n, err := strconv.Atoi(strings.TrimSpace(os.Getenv("EVOBGP_AUTH_RATE_LIMIT"))); err == nil && n > 0 {
+		limit = n
+	}
+	return &authRateLimiter{
+		hits:   make(map[string][]time.Time),
+		limit:  limit,
+		window: time.Minute,
+	}
+}
+
+func (l *authRateLimiter) allow(ip string) bool {
+	if l == nil {
+		return true
+	}
+	now := time.Now()
+	l.mu.Lock()
+	defer l.mu.Unlock()
+	cut := now.Add(-l.window)
+	arr := l.hits[ip]
+	kept := arr[:0]
+	for _, t := range arr {
+		if t.After(cut) {
+			kept = append(kept, t)
+		}
+	}
+	if len(kept) >= l.limit {
+		l.hits[ip] = kept
+		return false
+	}
+	kept = append(kept, now)
+	l.hits[ip] = kept
+	return true
+}
+
+func (s *Server) withAuthRateLimit(next http.HandlerFunc) http.HandlerFunc {
+	if s.authLimiter == nil {
+		s.authLimiter = newAuthRateLimiter()
+	}
+	return func(w http.ResponseWriter, r *http.Request) {
+		ip := clientIP(r)
+		if !s.authLimiter.allow(ip) {
+			writeProblem(w, http.StatusTooManyRequests, "Too Many Requests", "auth rate limit exceeded")
+			return
+		}
+		next(w, r)
+	}
+}

internal/httpapi/routes.go

@@ -30,12 +30,12 @@ func (s *Server) Handler() http.Handler {
 	s.registerV1(v1)
 	wrappedV1 := http.StripPrefix("/v1", v1)
 
-	s.mux.Handle("GET /metrics", observability.MetricsHandler())
+	s.mux.Handle("GET /metrics", observability.ProtectMetrics(observability.MetricsHandler()))
 	s.mux.HandleFunc("GET /version", s.handleVersion)
 	s.mux.HandleFunc("GET /v1/health", s.handleHealth)
 	s.mux.HandleFunc("GET /v1/ready", s.handleReady)
 	s.mux.HandleFunc("GET /v1/version", s.handleVersion)
-	s.mux.HandleFunc("GET /v1/auth/config", s.handleAuthConfigPublic)
+	s.mux.HandleFunc("GET /v1/auth/config", s.withAuthRateLimit(s.handleAuthConfigPublic))
 	// Firewall subsystem moved to the standalone EvoFirewall service; see docs/firewall.md.
 	// Registered on the public mux so it wins over the "/v1/" subtree below regardless of auth.
 	s.mux.HandleFunc("/v1/firewall/", s.handleFirewallGone)

internal/httpapi/server.go

@@ -29,6 +29,7 @@ type Server struct {
 	maintConfig             *maintenance.ConfigProvider
 	maintStats              *maintenance.DBStatsProvider
 	jobs                    *jobs.Registry
+	authLimiter             *authRateLimiter
 	bundlePriv              ed25519.PrivateKey
 	keyResolver             *apiKeyResolver
 	firewallResolver        *firewallTokenResolver