Additional security and hardening.

middleware/security.go

@@ -0,0 +1,24 @@
+package middleware
+
+import "net/http"
+
+// Redirects all HTTP to HTTPS (only in production)
+func EnforceHTTPS(next http.Handler, enabled bool) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if enabled && r.Header.Get("X-Forwarded-Proto") != "https" && r.TLS == nil {
+			http.Redirect(w, r, "https://"+r.Host+r.RequestURI, http.StatusMovedPermanently)
+			return
+		}
+		next.ServeHTTP(w, r)
+	})
+}
+
+func SecureHeaders(next http.Handler) http.Handler {
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Security-Policy", "default-src 'self'")
+		w.Header().Set("X-Content-Type-Options", "nosniff")
+		w.Header().Set("X-Frame-Options", "DENY")
+		w.Header().Set("X-XSS-Protection", "1; mode=block")
+		next.ServeHTTP(w, r)
+	})
+}