From 21b08cb044265ed1185d0a858b3b388928e59f7f Mon Sep 17 00:00:00 2001
From: fiatjaf <fiatjaf@gmail.com>
Date: Wed, 27 Dec 2023 12:30:23 -0300
Subject: [PATCH] fix closing of closed ws.Authed channel when client AUTHs
 twice.

---
 handlers.go  | 7 +++++--
 utils.go     | 3 +++
 websocket.go | 2 ++
 3 files changed, 10 insertions(+), 2 deletions(-)

diff --git a/handlers.go b/handlers.go
index c36c6d7..b3e95b8 100644
--- a/handlers.go
+++ b/handlers.go
@@ -50,7 +50,6 @@ func (rl *Relay) HandleWebsocket(w http.ResponseWriter, r *http.Request) {
 		conn:      conn,
 		Request:   r,
 		Challenge: hex.EncodeToString(challenge),
-		Authed:    make(chan struct{}),
 	}
 
 	ctx, cancel := context.WithCancel(
@@ -204,7 +203,11 @@ func (rl *Relay) HandleWebsocket(w http.ResponseWriter, r *http.Request) {
 					wsBaseUrl := strings.Replace(rl.ServiceURL, "http", "ws", 1)
 					if pubkey, ok := nip42.ValidateAuthEvent(&env.Event, ws.Challenge, wsBaseUrl); ok {
 						ws.AuthedPublicKey = pubkey
-						close(ws.Authed)
+						ws.authLock.Lock()
+						if ws.Authed != nil {
+							close(ws.Authed)
+						}
+						ws.authLock.Unlock()
 						ws.WriteJSON(nostr.OKEnvelope{EventID: env.Event.ID, OK: true})
 					} else {
 						ws.WriteJSON(nostr.OKEnvelope{EventID: env.Event.ID, OK: false, Reason: "error: failed to authenticate"})
diff --git a/utils.go b/utils.go
index 7681ac0..3f64313 100644
--- a/utils.go
+++ b/utils.go
@@ -14,6 +14,9 @@ const (
 
 func RequestAuth(ctx context.Context) {
 	ws := GetConnection(ctx)
+	ws.authLock.Lock()
+	ws.Authed = make(chan struct{})
+	ws.authLock.Unlock()
 	ws.WriteJSON(nostr.AuthEnvelope{Challenge: &ws.Challenge})
 }
 
diff --git a/websocket.go b/websocket.go
index 9f75d69..f00a636 100644
--- a/websocket.go
+++ b/websocket.go
@@ -18,6 +18,8 @@ type WebSocket struct {
 	Challenge       string
 	AuthedPublicKey string
 	Authed          chan struct{}
+
+	authLock sync.Mutex
 }
 
 func (ws *WebSocket) WriteJSON(any any) error {