From b5a7213cdb0b3c4a9d22013851cf6f32db30b1b8 Mon Sep 17 00:00:00 2001
From: Seraph91P <8904984+Serph91P@users.noreply.github.com>
Date: Tue, 21 Jul 2026 16:43:45 +0000
Subject: [PATCH] fix: preserve pending registration chain

Backwards-compatible registrations do not receive a wg/connect response.
Do not let them replace the chain ID of a normal registration that may
already be in flight.
---
 newt/handlers.go | 4 +++-
 newt/ping.go     | 3 ++-
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/newt/handlers.go b/newt/handlers.go
index 55c7f4e..3f57a11 100644
--- a/newt/handlers.go
+++ b/newt/handlers.go
@@ -1010,7 +1010,9 @@ func (n *Newt) registerHandlers(ctx context.Context) {
 		}
 
 		bcChainId := generateChainId()
-		n.pendingRegisterChainId = bcChainId
+		// Pangolin intentionally does not answer backwards-compatible
+		// registrations with newt/wg/connect. Do not replace the chain ID of
+		// the real registration while its response may already be in flight.
 		if err := n.client.SendMessage(topicWGRegister, map[string]interface{}{
 			"publicKey":           n.publicKey.String(),
 			"newtVersion":         n.config.Version,
diff --git a/newt/ping.go b/newt/ping.go
index 8ea7954..4126231 100644
--- a/newt/ping.go
+++ b/newt/ping.go
@@ -280,7 +280,8 @@ func (n *Newt) startPingCheck(fn pingFunc, serverIP, tunnelID string) chan struc
 							"chainId": pingChainId,
 						}, 3*time.Second)
 						bcChainId := generateChainId()
-						n.pendingRegisterChainId = bcChainId
+						// This compatibility message has no wg/connect response and must
+						// not supersede the pending real registration chain.
 						if err := n.client.SendMessage("newt/wg/register", map[string]interface{}{
 							"publicKey":           n.publicKey.String(),
 							"backwardsCompatible": true,