From 1c799b305da6af949a0300a9466af83339417047 Mon Sep 17 00:00:00 2001
From: Neil Alexander <neilalexander@users.noreply.github.com>
Date: Thu, 4 Jan 2018 13:31:48 +0000
Subject: [PATCH] Add support for specifying tun device name

---
 src/yggdrasil/debug.go | 8 ++++----
 src/yggdrasil/tun.go   | 6 ++++--
 yggdrasil.go           | 6 ++++--
 3 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/src/yggdrasil/debug.go b/src/yggdrasil/debug.go
index f6410b46..2ead581e 100644
--- a/src/yggdrasil/debug.go
+++ b/src/yggdrasil/debug.go
@@ -196,14 +196,14 @@ func (c *Core) DEBUG_getAddr() *address {
   return address_addrForNodeID(&c.dht.nodeID)
 }
 
-func (c *Core) DEBUG_startTun() {
-  c.DEBUG_startTunWithMTU(1280)
+func (c *Core) DEBUG_startTun(ifname string) {
+  c.DEBUG_startTunWithMTU(ifname, 1280)
 }
 
-func (c *Core) DEBUG_startTunWithMTU(mtu int) {
+func (c *Core) DEBUG_startTunWithMTU(ifname string, mtu int) {
   addr := c.DEBUG_getAddr()
   straddr := fmt.Sprintf("%s/%v", net.IP(addr[:]).String(), 8*len(address_prefix))
-  err := c.tun.setup(straddr, mtu)
+  err := c.tun.setup(ifname, straddr, mtu)
   if err != nil { panic(err) }
   go c.tun.read()
   go c.tun.write()
diff --git a/src/yggdrasil/tun.go b/src/yggdrasil/tun.go
index c3ae4fe6..95a81017 100644
--- a/src/yggdrasil/tun.go
+++ b/src/yggdrasil/tun.go
@@ -18,8 +18,10 @@ func (tun *tunDevice) init(core *Core) {
   tun.core = core
 }
 
-func (tun *tunDevice) setup(addr string, mtu int) error {
-	iface, err := water.New(water.Config{ DeviceType: water.TUN })
+func (tun *tunDevice) setup(ifname string, addr string, mtu int) error {
+        config := water.Config{ DeviceType: water.TUN }
+        if ifname != "" && ifname != "auto" { config.Name = ifname }
+	iface, err := water.New(config)
 	if err != nil { panic(err) }
   tun.iface = iface
   tun.mtu = mtu //1280 // Lets default to the smallest thing allowed for now
diff --git a/yggdrasil.go b/yggdrasil.go
index aa8e53c6..21cd08d5 100644
--- a/yggdrasil.go
+++ b/yggdrasil.go
@@ -35,6 +35,7 @@ type nodeConfig struct {
   SigPub string
   SigPriv string
   Multicast bool
+  IfName string
 }
 
 type node struct {
@@ -80,6 +81,7 @@ func generateConfig() *nodeConfig {
   cfg.SigPriv = hex.EncodeToString(spriv[:])
   cfg.Peers = []string{}
   cfg.Multicast = true
+  cfg.IfName = "auto"
   return &cfg
 }
 
@@ -182,8 +184,8 @@ func main() {
   n := node{}
   n.init(cfg, logger)
   logger.Println("Starting tun...")
-  n.core.DEBUG_startTun() // 1280, the smallest supported MTU
-  //n.core.DEBUG_startTunWithMTU(65535) // Largest supported MTU
+  n.core.DEBUG_startTun(cfg.IfName) // 1280, the smallest supported MTU
+  //n.core.DEBUG_startTunWithMTU(cfg.IfName, 65535) // Largest supported MTU
   defer func() { 
     logger.Println("Closing...")
     n.core.DEBUG_stopTun()