From a930c2aecf415bba1233e7b7aaa77f0d39ee6709 Mon Sep 17 00:00:00 2001
From: Zoltan Papp <zoltan.pmail@gmail.com>
Date: Thu, 13 Feb 2025 15:48:10 +0100
Subject: [PATCH] Fix priority handling (#3313)

---
 client/internal/peer/conn.go | 30 +++++++++++++++++++++++++-----
 1 file changed, 25 insertions(+), 5 deletions(-)

diff --git a/client/internal/peer/conn.go b/client/internal/peer/conn.go
index 7caafa53d31..8bbea6a2b42 100644
--- a/client/internal/peer/conn.go
+++ b/client/internal/peer/conn.go
@@ -2,6 +2,7 @@ package peer
 
 import (
 	"context"
+	"fmt"
 	"math/rand"
 	"net"
 	"os"
@@ -28,9 +29,25 @@ import (
 
 type ConnPriority int
 
+func (cp ConnPriority) String() string {
+	switch cp {
+	case connPriorityNone:
+		return "None"
+	case connPriorityRelay:
+		return "PriorityRelay"
+	case connPriorityICETurn:
+		return "PriorityICETurn"
+	case connPriorityICEP2P:
+		return "PriorityICEP2P"
+	default:
+		return fmt.Sprintf("ConnPriority(%d)", cp)
+	}
+}
+
 const (
 	defaultWgKeepAlive = 25 * time.Second
 
+	connPriorityNone    ConnPriority = 0
 	connPriorityRelay   ConnPriority = 1
 	connPriorityICETurn ConnPriority = 2
 	connPriorityICEP2P  ConnPriority = 3
@@ -299,9 +316,10 @@ func (conn *Conn) onICEConnectionIsReady(priority ConnPriority, iceConnInfo ICEC
 		return
 	}
 
-	conn.log.Debugf("ICE connection is ready")
-
+	// this never should happen, because Relay is the lower priority and ICE always close the deprecated connection before upgrade
+	// todo consider to remove this check
 	if conn.currentConnPriority > priority {
+		conn.log.Infof("current connection priority (%s) is higher than the new one (%s), do not upgrade connection", conn.currentConnPriority, priority)
 		conn.statusICE.Set(StatusConnected)
 		conn.updateIceState(iceConnInfo)
 		return
@@ -357,7 +375,6 @@ func (conn *Conn) onICEConnectionIsReady(priority ConnPriority, iceConnInfo ICEC
 	conn.doOnConnected(iceConnInfo.RosenpassPubKey, iceConnInfo.RosenpassAddr)
 }
 
-// todo review to make sense to handle connecting and disconnected status also?
 func (conn *Conn) onICEStateDisconnected() {
 	conn.mu.Lock()
 	defer conn.mu.Unlock()
@@ -376,7 +393,7 @@ func (conn *Conn) onICEStateDisconnected() {
 
 	// switch back to relay connection
 	if conn.isReadyToUpgrade() {
-		conn.log.Debugf("ICE disconnected, set Relay to active connection")
+		conn.log.Infof("ICE disconnected, set Relay to active connection")
 		conn.wgProxyRelay.Work()
 
 		if err := conn.configureWGEndpoint(conn.wgProxyRelay.EndpointAddr()); err != nil {
@@ -384,6 +401,9 @@ func (conn *Conn) onICEStateDisconnected() {
 		}
 		conn.workerRelay.EnableWgWatcher(conn.ctx)
 		conn.currentConnPriority = connPriorityRelay
+	} else {
+		conn.log.Infof("ICE disconnected, do not switch to Relay. Reset priority to: %s", connPriorityNone.String())
+		conn.currentConnPriority = connPriorityNone
 	}
 
 	changed := conn.statusICE.Get() != StatusDisconnected
@@ -427,7 +447,7 @@ func (conn *Conn) onRelayConnectionIsReady(rci RelayConnInfo) {
 	conn.log.Infof("created new wgProxy for relay connection: %s", wgProxy.EndpointAddr().String())
 
 	if conn.iceP2PIsActive() {
-		conn.log.Debugf("do not switch to relay because current priority is: %v", conn.currentConnPriority)
+		conn.log.Debugf("do not switch to relay because current priority is: %s", conn.currentConnPriority.String())
 		conn.setRelayedProxy(wgProxy)
 		conn.statusRelay.Set(StatusConnected)
 		conn.updateRelayStatus(rci.relayedConn.RemoteAddr().String(), rci.rosenpassPubKey)