Initial public release: Nym-native anonymous submission system

End-to-end verified pipeline (browser -> HTTP relay -> Nym mixnet -> reader).
Client-side X25519+HKDF+AES-GCM-256, no-log blind relay, AGPL-3.0.

2 files changed, 52 insertions, 0 deletions

diff --git a/internal/handler/static.go b/internal/handler/static.go
new file mode 100644
index 0000000..bf2aaec
--- /dev/null
+++ b/internal/handler/static.go
@@ -0,0 +1,19 @@
+package handler
+
+import (
+	"net/http"
+)
+
+func Static(dir string) http.Handler {
+	fs := http.FileServer(http.Dir(dir))
+	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Security headers on every response.
+		w.Header().Set("Content-Security-Policy", "default-src 'self'; script-src 'self'; style-src 'self'")
+		w.Header().Set("X-Content-Type-Options", "nosniff")
+		w.Header().Set("Referrer-Policy", "no-referrer")
+		w.Header().Set("Permissions-Policy", "geolocation=(), microphone=(), camera=()")
+		w.Header().Set("X-Frame-Options", "DENY")
+		w.Header().Set("Cache-Control", "no-store")
+		fs.ServeHTTP(w, r)
+	})
+}
diff --git a/internal/handler/submit.go b/internal/handler/submit.go
new file mode 100644
index 0000000..15251cf
--- /dev/null
+++ b/internal/handler/submit.go
@@ -0,0 +1,33 @@
+package handler
+
+import (
+	"net/http"
+	"nymdrop/internal/relay"
+)
+
+type Submit struct {
+	relay *relay.Relay
+}
+
+func NewSubmit(r *relay.Relay) *Submit {
+	return &Submit{relay: r}
+}
+
+func (s *Submit) ServeHTTP(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodPost {
+		http.Error(w, "method not allowed", http.StatusMethodNotAllowed)
+		return
+	}
+
+	r.Body = http.MaxBytesReader(w, r.Body, 10*1024*1024)
+	defer r.Body.Close()
+
+	if err := s.relay.Forward(r.Body); err != nil {
+		// Generic error — reveal nothing about internals.
+		http.Error(w, "error", http.StatusInternalServerError)
+		return
+	}
+
+	w.WriteHeader(http.StatusOK)
+	w.Write([]byte("ok"))
+}