From bbd1246f7bf9615941a77608c63260fa6b744e00 Mon Sep 17 00:00:00 2001
From: Neil Alexander <neilalexander@users.noreply.github.com>
Date: Mon, 22 Apr 2019 11:49:47 +0100
Subject: [PATCH] Fix bug in mask generation for outbound dials, change iface
 reader mutexes to read-only locks unless RW is needed

---
 src/tuntap/tun.go       | 26 ++++++++++++++++----------
 src/yggdrasil/dialer.go |  6 +++---
 2 files changed, 19 insertions(+), 13 deletions(-)

diff --git a/src/tuntap/tun.go b/src/tuntap/tun.go
index 746293d4..3bdbde25 100644
--- a/src/tuntap/tun.go
+++ b/src/tuntap/tun.go
@@ -260,9 +260,9 @@ func (tun *TunAdapter) ifaceReader() error {
 		}
 		dstNodeID, dstNodeIDMask = dstAddr.GetNodeIDandMask()
 		// Do we have an active connection for this node ID?
-		tun.mutex.Lock()
+		tun.mutex.RLock()
 		if conn, isIn := tun.conns[*dstNodeID]; isIn {
-			tun.mutex.Unlock()
+			tun.mutex.RUnlock()
 			w, err := conn.Write(bs[:n])
 			if err != nil {
 				tun.log.Errorln("TUN/TAP conn write error:", err)
@@ -273,14 +273,20 @@ func (tun *TunAdapter) ifaceReader() error {
 				continue
 			}
 		} else {
-			if conn, err := tun.dialer.DialByNodeIDandMask(dstNodeID, dstNodeIDMask); err == nil {
-				tun.conns[*dstNodeID] = &conn
-				tun.mutex.Unlock()
-				go tun.connReader(&conn)
-			} else {
-				tun.mutex.Unlock()
-				tun.log.Errorln("TUN/TAP dial error:", err)
-			}
+			tun.mutex.RUnlock()
+			func() {
+				tun.mutex.Lock()
+				defer tun.mutex.Unlock()
+				if conn, err := tun.dialer.DialByNodeIDandMask(dstNodeID, dstNodeIDMask); err == nil {
+					tun.log.Debugln("Opening new session connection")
+					tun.log.Debugln("Node:", dstNodeID)
+					tun.log.Debugln("Mask:", dstNodeIDMask)
+					tun.conns[*dstNodeID] = &conn
+					go tun.connReader(&conn)
+				} else {
+					tun.log.Errorln("TUN/TAP dial error:", err)
+				}
+			}()
 		}
 
 		/*if !r.cryptokey.isValidSource(srcAddr, addrlen) {
diff --git a/src/yggdrasil/dialer.go b/src/yggdrasil/dialer.go
index 49ce0a98..bd4b87e2 100644
--- a/src/yggdrasil/dialer.go
+++ b/src/yggdrasil/dialer.go
@@ -35,7 +35,7 @@ func (d *Dialer) Dial(network, address string) (Conn, error) {
 				return Conn{}, err
 			}
 			copy(nodeID[:], dest)
-			for idx := 0; idx <= len; idx++ {
+			for idx := 0; idx < len; idx++ {
 				nodeMask[idx/8] |= 0x80 >> byte(idx%8)
 			}
 		} else {
@@ -65,8 +65,8 @@ func (d *Dialer) DialByNodeIDandMask(nodeID, nodeMask *crypto.NodeID) (Conn, err
 		nodeMask: nodeMask,
 		recv:     make(chan *wire_trafficPacket, 32),
 	}
-	conn.core.router.doAdmin(func() {
+	conn.core.router.admin <- func() {
 		conn.startSearch()
-	})
+	}
 	return conn, nil
 }