From b9a2f719a02eb1fcb64e55a84201cbc477e47974 Mon Sep 17 00:00:00 2001
From: Asim Aslam <asim@aslam.me>
Date: Wed, 4 Sep 2019 18:46:20 +0100
Subject: [PATCH 1/2] Add some fixes

---
 tunnel/default.go | 68 +++++++++++++++++++++++++++++++++--------------
 tunnel/link.go    |  2 +-
 2 files changed, 49 insertions(+), 21 deletions(-)

diff --git a/tunnel/default.go b/tunnel/default.go
index 5d27809a..add48eb8 100644
--- a/tunnel/default.go
+++ b/tunnel/default.go
@@ -220,14 +220,6 @@ func (t *tun) process() {
 					continue
 				}
 
-				// if we're picking the link check the id
-				// this is where we explicitly set the link
-				// in a message received via the listen method
-				if len(msg.link) > 0 && link.id != msg.link {
-					err = errors.New("link not found")
-					continue
-				}
-
 				// if the link was a loopback accepted connection
 				// and the message is being sent outbound via
 				// a dialled connection don't use this link
@@ -252,6 +244,14 @@ func (t *tun) process() {
 					if !ok {
 						continue
 					}
+				} else {
+					// if we're picking the link check the id
+					// this is where we explicitly set the link
+					// in a message received via the listen method
+					if len(msg.link) > 0 && link.id != msg.link {
+						err = errors.New("link not found")
+						continue
+					}
 				}
 
 				// send the message via the current link
@@ -364,6 +364,7 @@ func (t *tun) listen(link *link) {
 		case "connect":
 			log.Debugf("Tunnel link %s received connect message", link.Remote())
 
+			link.Lock()
 			// are we connecting to ourselves?
 			if id == t.id {
 				link.loopback = true
@@ -374,6 +375,7 @@ func (t *tun) listen(link *link) {
 			link.id = id
 			// set as connected
 			link.connected = true
+			link.Unlock()
 
 			// save the link once connected
 			t.Lock()
@@ -417,10 +419,19 @@ func (t *tun) listen(link *link) {
 			continue
 		// a new connection dialled outbound
 		case "open":
+			log.Debugf("Tunnel link %s received open %s %s", link.id, channel, sessionId)
 			// we just let it pass through to be processed
 		// an accept returned by the listener
 		case "accept":
-
+			s, exists := t.getSession(channel, sessionId)
+			// we don't need this
+			if exists && s.multicast {
+				s.accepted = true
+				continue
+			}
+			if exists && s.accepted {
+				continue
+			}
 		// a continued session
 		case "session":
 			// process message
@@ -725,6 +736,12 @@ func (t *tun) Connect() error {
 }
 
 func (t *tun) close() error {
+	// close all the sessions
+	for id, s := range t.sessions {
+		s.Close()
+		delete(t.sessions, id)
+	}
+
 	// close all the links
 	for node, link := range t.links {
 		link.Send(&transport.Message{
@@ -768,12 +785,6 @@ func (t *tun) Close() error {
 	case <-t.closed:
 		return nil
 	default:
-		// close all the sessions
-		for id, s := range t.sessions {
-			s.Close()
-			delete(t.sessions, id)
-		}
-		// close the connection
 		close(t.closed)
 		t.connected = false
 
@@ -814,11 +825,16 @@ func (t *tun) Dial(channel string, opts ...DialOption) (Session, error) {
 	// set the dial timeout
 	c.timeout = options.Timeout
 
-	// don't bother with the song and dance below
-	// we're just going to assume things come online
-	// as and when.
-	if c.multicast {
-		return c, nil
+	now := time.Now()
+
+	after := func() time.Duration {
+		d := time.Since(now)
+		// dial timeout minus time since
+		wait := options.Timeout - d
+		if wait < time.Duration(0) {
+			return time.Duration(0)
+		}
+		return wait
 	}
 
 	// non multicast so we need to find the link
@@ -846,7 +862,17 @@ func (t *tun) Dial(channel string, opts ...DialOption) (Session, error) {
 		// send the discovery message
 		t.send <- msg
 
+		// don't bother waiting around
+		// we're just going to assume things come online
+		if c.multicast {
+			c.discovered = true
+			c.accepted = true
+			return c, nil
+		}
+
 		select {
+		case <-time.After(after()):
+			return nil, ErrDialTimeout
 		case err := <-c.errChan:
 			if err != nil {
 				return nil, err
@@ -859,6 +885,8 @@ func (t *tun) Dial(channel string, opts ...DialOption) (Session, error) {
 			if msg.typ != "announce" {
 				return nil, errors.New("failed to discover channel")
 			}
+		case <-time.After(after()):
+			return nil, ErrDialTimeout
 		}
 	}
 
diff --git a/tunnel/link.go b/tunnel/link.go
index 9470ef6a..38c80825 100644
--- a/tunnel/link.go
+++ b/tunnel/link.go
@@ -97,7 +97,7 @@ func (l *link) Close() error {
 		return nil
 	default:
 		close(l.closed)
-		return l.Socket.Close()
+		return nil
 	}
 
 	return nil

From d8a1b479544893035d8dbc1e1caf6d8d5d27967c Mon Sep 17 00:00:00 2001
From: Asim Aslam <asim@aslam.me>
Date: Wed, 4 Sep 2019 18:48:43 +0100
Subject: [PATCH 2/2] Remove lock from link

---
 tunnel/link.go | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/tunnel/link.go b/tunnel/link.go
index 38c80825..b360e826 100644
--- a/tunnel/link.go
+++ b/tunnel/link.go
@@ -89,9 +89,6 @@ func (l *link) Id() string {
 }
 
 func (l *link) Close() error {
-	l.Lock()
-	defer l.Unlock()
-
 	select {
 	case <-l.closed:
 		return nil