Merge pull request #297 from neilalexander/nodeconfig

Use central NodeConfig for components

cmd/yggdrasil/main.go

@@ -9,10 +9,8 @@ import (
 	"log"
 	"os"
 	"os/signal"
-	"regexp"
 	"strings"
 	"syscall"
-	"time"
 
 	"golang.org/x/text/encoding/unicode"
 
@@ -31,57 +29,18 @@ type node struct {
 	core Core
 }
 
-// Generates a new configuration and returns it in HJSON format. This is used
+func readConfig(useconf *bool, useconffile *string, normaliseconf *bool) *nodeConfig {
-// with -genconf.
-func doGenconf(isjson bool) string {
-	cfg := config.GenerateConfig(false)
-	var bs []byte
-	var err error
-	if isjson {
-		bs, err = json.MarshalIndent(cfg, "", "  ")
-	} else {
-		bs, err = hjson.Marshal(cfg)
-	}
-	if err != nil {
-		panic(err)
-	}
-	return string(bs)
-}
-
-// The main function is responsible for configuring and starting Yggdrasil.
-func main() {
-	// Configure the command line parameters.
-	genconf := flag.Bool("genconf", false, "print a new config to stdout")
-	useconf := flag.Bool("useconf", false, "read HJSON/JSON config from stdin")
-	useconffile := flag.String("useconffile", "", "read HJSON/JSON config from specified file path")
-	normaliseconf := flag.Bool("normaliseconf", false, "use in combination with either -useconf or -useconffile, outputs your configuration normalised")
-	confjson := flag.Bool("json", false, "print configuration from -genconf or -normaliseconf as JSON instead of HJSON")
-	autoconf := flag.Bool("autoconf", false, "automatic mode (dynamic IP, peer with IPv6 neighbors)")
-	version := flag.Bool("version", false, "prints the version of this build")
-	flag.Parse()
-
-	var cfg *nodeConfig
-	switch {
-	case *version:
-		fmt.Println("Build name:", yggdrasil.GetBuildName())
-		fmt.Println("Build version:", yggdrasil.GetBuildVersion())
-		os.Exit(0)
-	case *autoconf:
-		// Use an autoconf-generated config, this will give us random keys and
-		// port numbers, and will use an automatically selected TUN/TAP interface.
-		cfg = config.GenerateConfig(true)
-	case *useconffile != "" || *useconf:
 	// Use a configuration file. If -useconf, the configuration will be read
 	// from stdin. If -useconffile, the configuration will be read from the
 	// filesystem.
-		var configjson []byte
+	var conf []byte
 	var err error
 	if *useconffile != "" {
 		// Read the file from the filesystem
-			configjson, err = ioutil.ReadFile(*useconffile)
+		conf, err = ioutil.ReadFile(*useconffile)
 	} else {
 		// Read the file from stdin.
-			configjson, err = ioutil.ReadAll(os.Stdin)
+		conf, err = ioutil.ReadAll(os.Stdin)
 	}
 	if err != nil {
 		panic(err)
@@ -90,11 +49,11 @@ func main() {
 	// throwing everywhere when it's converting things into UTF-16 for the hell
 	// of it - remove it and decode back down into UTF-8. This is necessary
 	// because hjson doesn't know what to do with UTF-16 and will panic
-		if bytes.Compare(configjson[0:2], []byte{0xFF, 0xFE}) == 0 ||
+	if bytes.Compare(conf[0:2], []byte{0xFF, 0xFE}) == 0 ||
-			bytes.Compare(configjson[0:2], []byte{0xFE, 0xFF}) == 0 {
+		bytes.Compare(conf[0:2], []byte{0xFE, 0xFF}) == 0 {
 		utf := unicode.UTF16(unicode.BigEndian, unicode.UseBOM)
 		decoder := utf.NewDecoder()
-			configjson, err = decoder.Bytes(configjson)
+		conf, err = decoder.Bytes(conf)
 		if err != nil {
 			panic(err)
 		}
@@ -103,9 +62,9 @@ func main() {
 	// then parse the configuration we loaded above on top of it. The effect
 	// of this is that any configuration item that is missing from the provided
 	// configuration will use a sane default.
-		cfg = config.GenerateConfig(false)
+	cfg := config.GenerateConfig(false)
 	var dat map[string]interface{}
-		if err := hjson.Unmarshal(configjson, &dat); err != nil {
+	if err := hjson.Unmarshal(conf, &dat); err != nil {
 		panic(err)
 	}
 	confJson, err := json.Marshal(dat)
@@ -179,6 +138,53 @@ func main() {
 	if err = mapstructure.Decode(dat, &cfg); err != nil {
 		panic(err)
 	}
+
+	return cfg
+}
+
+// Generates a new configuration and returns it in HJSON format. This is used
+// with -genconf.
+func doGenconf(isjson bool) string {
+	cfg := config.GenerateConfig(false)
+	var bs []byte
+	var err error
+	if isjson {
+		bs, err = json.MarshalIndent(cfg, "", "  ")
+	} else {
+		bs, err = hjson.Marshal(cfg)
+	}
+	if err != nil {
+		panic(err)
+	}
+	return string(bs)
+}
+
+// The main function is responsible for configuring and starting Yggdrasil.
+func main() {
+	// Configure the command line parameters.
+	genconf := flag.Bool("genconf", false, "print a new config to stdout")
+	useconf := flag.Bool("useconf", false, "read HJSON/JSON config from stdin")
+	useconffile := flag.String("useconffile", "", "read HJSON/JSON config from specified file path")
+	normaliseconf := flag.Bool("normaliseconf", false, "use in combination with either -useconf or -useconffile, outputs your configuration normalised")
+	confjson := flag.Bool("json", false, "print configuration from -genconf or -normaliseconf as JSON instead of HJSON")
+	autoconf := flag.Bool("autoconf", false, "automatic mode (dynamic IP, peer with IPv6 neighbors)")
+	version := flag.Bool("version", false, "prints the version of this build")
+	flag.Parse()
+
+	var cfg *nodeConfig
+	var err error
+	switch {
+	case *version:
+		fmt.Println("Build name:", yggdrasil.GetBuildName())
+		fmt.Println("Build version:", yggdrasil.GetBuildVersion())
+		os.Exit(0)
+	case *autoconf:
+		// Use an autoconf-generated config, this will give us random keys and
+		// port numbers, and will use an automatically selected TUN/TAP interface.
+		cfg = config.GenerateConfig(true)
+	case *useconffile != "" || *useconf:
+		// Read the configuration from either stdin or from the filesystem
+		cfg = readConfig(useconf, useconffile, normaliseconf)
 		// If the -normaliseconf option was specified then remarshal the above
 		// configuration and print it back to stdout. This lets the user update
 		// their configuration file with newly mapped names (like above) or to
@@ -214,15 +220,6 @@ func main() {
 	// Setup the Yggdrasil node itself. The node{} type includes a Core, so we
 	// don't need to create this manually.
 	n := node{}
-	// Check to see if any multicast interface expressions were provided in the
-	// config. If they were then set them now.
-	for _, ll := range cfg.MulticastInterfaces {
-		ifceExpr, err := regexp.Compile(ll)
-		if err != nil {
-			panic(err)
-		}
-		n.core.AddMulticastInterfaceExpr(ifceExpr)
-	}
 	// Now that we have a working configuration, we can now actually start
 	// Yggdrasil. This will start the router, switch, DHT node, TCP and UDP
 	// sockets, TUN/TAP adapter and multicast discovery port.
@@ -235,27 +232,6 @@ func main() {
 	for _, pBoxStr := range cfg.AllowedEncryptionPublicKeys {
 		n.core.AddAllowedEncryptionPublicKey(pBoxStr)
 	}
-	// If any static peers were provided in the configuration above then we should
-	// configure them. The loop ensures that disconnected peers will eventually
-	// be reconnected with.
-	go func() {
-		if len(cfg.Peers) == 0 && len(cfg.InterfacePeers) == 0 {
-			return
-		}
-		for {
-			for _, peer := range cfg.Peers {
-				n.core.AddPeer(peer, "")
-				time.Sleep(time.Second)
-			}
-			for intf, intfpeers := range cfg.InterfacePeers {
-				for _, peer := range intfpeers {
-					n.core.AddPeer(peer, intf)
-					time.Sleep(time.Second)
-				}
-			}
-			time.Sleep(time.Minute)
-		}
-	}()
 	// The Stop function ensures that the TUN/TAP adapter is correctly shut down
 	// before the program exits.
 	defer func() {
@@ -269,7 +245,9 @@ func main() {
 	logger.Printf("Your IPv6 subnet is %s", subnet.String())
 	// Catch interrupts from the operating system to exit gracefully.
 	c := make(chan os.Signal, 1)
+	r := make(chan os.Signal, 1)
 	signal.Notify(c, os.Interrupt, syscall.SIGTERM)
+	signal.Notify(r, os.Interrupt, syscall.SIGHUP)
 	// Create a function to capture the service being stopped on Windows.
 	winTerminate := func() {
 		c <- os.Interrupt
@@ -277,5 +255,18 @@ func main() {
 	minwinsvc.SetOnExit(winTerminate)
 	// Wait for the terminate/interrupt signal. Once a signal is received, the
 	// deferred Stop function above will run which will shut down TUN/TAP.
-	<-c
+	for {
+		select {
+		case _ = <-r:
+			if *useconffile != "" {
+				cfg = readConfig(useconf, useconffile, normaliseconf)
+				n.core.UpdateConfig(cfg)
+			} else {
+				logger.Println("Reloading config at runtime is only possible with -useconffile")
+			}
+		case _ = <-c:
+			goto exit
+		}
+	}
+exit:
 }

src/yggdrasil/adapter.go

@@ -6,6 +6,7 @@ type Adapter struct {
 	core        *Core
 	send        chan<- []byte
 	recv        <-chan []byte
+	reconfigure chan chan error
 }
 
 // Initialises the adapter.
@@ -13,4 +14,5 @@ func (adapter *Adapter) init(core *Core, send chan<- []byte, recv <-chan []byte)
 	adapter.core = core
 	adapter.send = send
 	adapter.recv = recv
+	adapter.reconfigure = make(chan chan error, 1)
 }

src/yggdrasil/admin.go

@@ -23,6 +23,7 @@ import (
 
 type admin struct {
 	core        *Core
+	reconfigure chan chan error
 	listenaddr  string
 	listener    net.Listener
 	handlers    []admin_handlerInfo
@@ -51,9 +52,25 @@ func (a *admin) addHandler(name string, args []string, handler func(admin_info)
 }
 
 // init runs the initial admin setup.
-func (a *admin) init(c *Core, listenaddr string) {
+func (a *admin) init(c *Core) {
 	a.core = c
-	a.listenaddr = listenaddr
+	a.reconfigure = make(chan chan error, 1)
+	go func() {
+		for {
+			e := <-a.reconfigure
+			a.core.configMutex.RLock()
+			if a.core.config.AdminListen != a.core.configOld.AdminListen {
+				a.listenaddr = a.core.config.AdminListen
+				a.close()
+				a.start()
+			}
+			a.core.configMutex.RUnlock()
+			e <- nil
+		}
+	}()
+	a.core.configMutex.RLock()
+	a.listenaddr = a.core.config.AdminListen
+	a.core.configMutex.RUnlock()
 	a.addHandler("list", []string{}, func(in admin_info) (admin_info, error) {
 		handlers := make(map[string]interface{})
 		for _, handler := range a.handlers {
@@ -331,7 +348,10 @@ func (a *admin) init(c *Core, listenaddr string) {
 		}
 		var box_pub_key, coords string
 		if in["box_pub_key"] == nil && in["coords"] == nil {
-			nodeinfo := []byte(a.core.nodeinfo.getNodeInfo())
+			var nodeinfo []byte
+			a.core.router.doAdmin(func() {
+				nodeinfo = []byte(a.core.router.nodeinfo.getNodeInfo())
+			})
 			var jsoninfo interface{}
 			if err := json.Unmarshal(nodeinfo, &jsoninfo); err != nil {
 				return admin_info{}, err
@@ -842,7 +862,7 @@ func (a *admin) admin_getNodeInfo(keyString, coordString string, nocache bool) (
 		copy(key[:], keyBytes)
 	}
 	if !nocache {
-		if response, err := a.core.nodeinfo.getCachedNodeInfo(key); err == nil {
+		if response, err := a.core.router.nodeinfo.getCachedNodeInfo(key); err == nil {
 			return response, nil
 		}
 	}
@@ -860,14 +880,14 @@ func (a *admin) admin_getNodeInfo(keyString, coordString string, nocache bool) (
 	}
 	response := make(chan *nodeinfoPayload, 1)
 	sendNodeInfoRequest := func() {
-		a.core.nodeinfo.addCallback(key, func(nodeinfo *nodeinfoPayload) {
+		a.core.router.nodeinfo.addCallback(key, func(nodeinfo *nodeinfoPayload) {
 			defer func() { recover() }()
 			select {
 			case response <- nodeinfo:
 			default:
 			}
 		})
-		a.core.nodeinfo.sendNodeInfo(key, coords, false)
+		a.core.router.nodeinfo.sendNodeInfo(key, coords, false)
 	}
 	a.core.router.doAdmin(sendNodeInfoRequest)
 	go func() {

src/yggdrasil/ckr.go

@@ -18,6 +18,7 @@ import (
 type cryptokey struct {
 	core        *Core
 	enabled     bool
+	reconfigure chan chan error
 	ipv4routes  []cryptokey_route
 	ipv6routes  []cryptokey_route
 	ipv4cache   map[address.Address]cryptokey_route
@@ -34,12 +35,75 @@ type cryptokey_route struct {
 // Initialise crypto-key routing. This must be done before any other CKR calls.
 func (c *cryptokey) init(core *Core) {
 	c.core = core
-	c.ipv4routes = make([]cryptokey_route, 0)
+	c.reconfigure = make(chan chan error, 1)
+	go func() {
+		for {
+			e := <-c.reconfigure
+			var err error
+			c.core.router.doAdmin(func() {
+				err = c.core.router.cryptokey.configure()
+			})
+			e <- err
+		}
+	}()
+
+	if err := c.configure(); err != nil {
+		c.core.log.Println("CKR configuration failed:", err)
+	}
+}
+
+// Configure the CKR routes - this must only ever be called from the router
+// goroutine, e.g. through router.doAdmin
+func (c *cryptokey) configure() error {
+	c.core.configMutex.RLock()
+	defer c.core.configMutex.RUnlock()
+
+	// Set enabled/disabled state
+	c.setEnabled(c.core.config.TunnelRouting.Enable)
+
+	// Clear out existing routes
 	c.ipv6routes = make([]cryptokey_route, 0)
+	c.ipv4routes = make([]cryptokey_route, 0)
+
+	// Add IPv6 routes
+	for ipv6, pubkey := range c.core.config.TunnelRouting.IPv6Destinations {
+		if err := c.addRoute(ipv6, pubkey); err != nil {
+			return err
+		}
+	}
+
+	// Add IPv4 routes
+	for ipv4, pubkey := range c.core.config.TunnelRouting.IPv4Destinations {
+		if err := c.addRoute(ipv4, pubkey); err != nil {
+			return err
+		}
+	}
+
+	// Clear out existing sources
+	c.ipv6sources = make([]net.IPNet, 0)
+	c.ipv4sources = make([]net.IPNet, 0)
+
+	// Add IPv6 sources
+	c.ipv6sources = make([]net.IPNet, 0)
+	for _, source := range c.core.config.TunnelRouting.IPv6Sources {
+		if err := c.addSourceSubnet(source); err != nil {
+			return err
+		}
+	}
+
+	// Add IPv4 sources
+	c.ipv4sources = make([]net.IPNet, 0)
+	for _, source := range c.core.config.TunnelRouting.IPv4Sources {
+		if err := c.addSourceSubnet(source); err != nil {
+			return err
+		}
+	}
+
+	// Wipe the caches
 	c.ipv4cache = make(map[address.Address]cryptokey_route, 0)
 	c.ipv6cache = make(map[address.Address]cryptokey_route, 0)
-	c.ipv4sources = make([]net.IPNet, 0)
+
-	c.ipv6sources = make([]net.IPNet, 0)
+	return nil
 }
 
 // Enable or disable crypto-key routing.

src/yggdrasil/core.go

@@ -2,11 +2,11 @@ package yggdrasil
 
 import (
 	"encoding/hex"
-	"fmt"
 	"io/ioutil"
 	"log"
 	"net"
-	"regexp"
+	"sync"
+	"time"
 
 	"github.com/yggdrasil-network/yggdrasil-go/src/address"
 	"github.com/yggdrasil-network/yggdrasil-go/src/config"
@@ -17,10 +17,20 @@ import (
 var buildName string
 var buildVersion string
 
+type module interface {
+	init(*Core, *config.NodeConfig) error
+	start() error
+}
+
 // The Core object represents the Yggdrasil node. You should create a Core
 // object for each Yggdrasil node you plan to run.
 type Core struct {
 	// This is the main data structure that holds everything else for a node
+	// We're going to keep our own copy of the provided config - that way we can
+	// guarantee that it will be covered by the mutex
+	config      config.NodeConfig // Active config
+	configOld   config.NodeConfig // Previous config
+	configMutex sync.RWMutex      // Protects both config and configOld
 	boxPub      crypto.BoxPubKey
 	boxPriv     crypto.BoxPrivKey
 	sigPub      crypto.SigPubKey
@@ -33,17 +43,12 @@ type Core struct {
 	admin       admin
 	searches    searches
 	multicast   multicast
-	nodeinfo    nodeinfo
 	tcp         tcpInterface
 	awdl        awdl
 	log         *log.Logger
-	ifceExpr    []*regexp.Regexp // the zone of link-local IPv6 peers must match this
 }
 
-func (c *Core) init(bpub *crypto.BoxPubKey,
+func (c *Core) init() error {
-	bpriv *crypto.BoxPrivKey,
-	spub *crypto.SigPubKey,
-	spriv *crypto.SigPrivKey) {
 	// TODO separate init and start functions
 	//  Init sets up structs
 	//  Start launches goroutines that depend on structs being set up
@@ -51,20 +56,104 @@ func (c *Core) init(bpub *crypto.BoxPubKey,
 	if c.log == nil {
 		c.log = log.New(ioutil.Discard, "", 0)
 	}
-	c.boxPub, c.boxPriv = *bpub, *bpriv
+
-	c.sigPub, c.sigPriv = *spub, *spriv
+	boxPubHex, err := hex.DecodeString(c.config.EncryptionPublicKey)
-	c.admin.core = c
+	if err != nil {
+		return err
+	}
+	boxPrivHex, err := hex.DecodeString(c.config.EncryptionPrivateKey)
+	if err != nil {
+		return err
+	}
+	sigPubHex, err := hex.DecodeString(c.config.SigningPublicKey)
+	if err != nil {
+		return err
+	}
+	sigPrivHex, err := hex.DecodeString(c.config.SigningPrivateKey)
+	if err != nil {
+		return err
+	}
+
+	copy(c.boxPub[:], boxPubHex)
+	copy(c.boxPriv[:], boxPrivHex)
+	copy(c.sigPub[:], sigPubHex)
+	copy(c.sigPriv[:], sigPrivHex)
+
+	c.admin.init(c)
 	c.searches.init(c)
 	c.dht.init(c)
 	c.sessions.init(c)
 	c.multicast.init(c)
 	c.peers.init(c)
 	c.router.init(c)
-	c.switchTable.init(c, c.sigPub) // TODO move before peers? before router?
+	c.switchTable.init(c) // TODO move before peers? before router?
+
+	return nil
 }
 
-// Get the current build name. This is usually injected if built from git,
+// If any static peers were provided in the configuration above then we should
-// or returns "unknown" otherwise.
+// configure them. The loop ensures that disconnected peers will eventually
+// be reconnected with.
+func (c *Core) addPeerLoop() {
+	for {
+		// Get the peers from the config - these could change!
+		c.configMutex.RLock()
+		peers := c.config.Peers
+		interfacepeers := c.config.InterfacePeers
+		c.configMutex.RUnlock()
+
+		// Add peers from the Peers section
+		for _, peer := range peers {
+			c.AddPeer(peer, "")
+			time.Sleep(time.Second)
+		}
+
+		// Add peers from the InterfacePeers section
+		for intf, intfpeers := range interfacepeers {
+			for _, peer := range intfpeers {
+				c.AddPeer(peer, intf)
+				time.Sleep(time.Second)
+			}
+		}
+
+		// Sit for a while
+		time.Sleep(time.Minute)
+	}
+}
+
+// UpdateConfig updates the configuration in Core and then signals the
+// various module goroutines to reconfigure themselves if needed
+func (c *Core) UpdateConfig(config *config.NodeConfig) {
+	c.configMutex.Lock()
+	c.configOld = c.config
+	c.config = *config
+	c.configMutex.Unlock()
+
+	components := []chan chan error{
+		c.admin.reconfigure,
+		c.searches.reconfigure,
+		c.dht.reconfigure,
+		c.sessions.reconfigure,
+		c.peers.reconfigure,
+		c.router.reconfigure,
+		c.router.tun.reconfigure,
+		c.router.cryptokey.reconfigure,
+		c.switchTable.reconfigure,
+		c.tcp.reconfigure,
+		c.multicast.reconfigure,
+	}
+
+	for _, component := range components {
+		response := make(chan error)
+		component <- response
+		if err := <-response; err != nil {
+			c.log.Println(err)
+		}
+	}
+}
+
+// GetBuildName gets the current build name. This is usually injected if built
+// from git, or returns "unknown" otherwise.
 func GetBuildName() string {
 	if buildName == "" {
 		return "unknown"
@@ -97,38 +186,14 @@ func (c *Core) Start(nc *config.NodeConfig, log *log.Logger) error {
 
 	c.log.Println("Starting up...")
 
-	var boxPub crypto.BoxPubKey
+	c.configMutex.Lock()
-	var boxPriv crypto.BoxPrivKey
+	c.config = *nc
-	var sigPub crypto.SigPubKey
+	c.configOld = c.config
-	var sigPriv crypto.SigPrivKey
+	c.configMutex.Unlock()
-	boxPubHex, err := hex.DecodeString(nc.EncryptionPublicKey)
-	if err != nil {
-		return err
-	}
-	boxPrivHex, err := hex.DecodeString(nc.EncryptionPrivateKey)
-	if err != nil {
-		return err
-	}
-	sigPubHex, err := hex.DecodeString(nc.SigningPublicKey)
-	if err != nil {
-		return err
-	}
-	sigPrivHex, err := hex.DecodeString(nc.SigningPrivateKey)
-	if err != nil {
-		return err
-	}
-	copy(boxPub[:], boxPubHex)
-	copy(boxPriv[:], boxPrivHex)
-	copy(sigPub[:], sigPubHex)
-	copy(sigPriv[:], sigPrivHex)
 
-	c.init(&boxPub, &boxPriv, &sigPub, &sigPriv)
+	c.init()
-	c.admin.init(c, nc.AdminListen)
 
-	c.nodeinfo.init(c)
+	if err := c.tcp.init(c); err != nil {
-	c.nodeinfo.setNodeInfo(nc.NodeInfo, nc.NodeInfoPrivacy)
-
-	if err := c.tcp.init(c, nc.Listen, nc.ReadTimeout); err != nil {
 		c.log.Println("Failed to start TCP interface")
 		return err
 	}
@@ -161,31 +226,6 @@ func (c *Core) Start(nc *config.NodeConfig, log *log.Logger) error {
 		return err
 	}
 
-	c.router.cryptokey.setEnabled(nc.TunnelRouting.Enable)
-	if c.router.cryptokey.isEnabled() {
-		c.log.Println("Crypto-key routing enabled")
-		for ipv6, pubkey := range nc.TunnelRouting.IPv6Destinations {
-			if err := c.router.cryptokey.addRoute(ipv6, pubkey); err != nil {
-				panic(err)
-			}
-		}
-		for _, source := range nc.TunnelRouting.IPv6Sources {
-			if c.router.cryptokey.addSourceSubnet(source); err != nil {
-				panic(err)
-			}
-		}
-		for ipv4, pubkey := range nc.TunnelRouting.IPv4Destinations {
-			if err := c.router.cryptokey.addRoute(ipv4, pubkey); err != nil {
-				panic(err)
-			}
-		}
-		for _, source := range nc.TunnelRouting.IPv4Sources {
-			if c.router.cryptokey.addSourceSubnet(source); err != nil {
-				panic(err)
-			}
-		}
-	}
-
 	if err := c.admin.start(); err != nil {
 		c.log.Println("Failed to start admin socket")
 		return err
@@ -196,12 +236,13 @@ func (c *Core) Start(nc *config.NodeConfig, log *log.Logger) error {
 		return err
 	}
 
-	ip := net.IP(c.router.addr[:]).String()
+	if err := c.router.tun.start(); err != nil {
-	if err := c.router.tun.start(nc.IfName, nc.IfTAPMode, fmt.Sprintf("%s/%d", ip, 8*len(address.GetPrefix())-1), nc.IfMTU); err != nil {
 		c.log.Println("Failed to start TUN/TAP")
 		return err
 	}
 
+	go c.addPeerLoop()
+
 	c.log.Println("Startup complete")
 	return nil
 }
@@ -250,12 +291,12 @@ func (c *Core) GetSubnet() *net.IPNet {
 
 // Gets the nodeinfo.
 func (c *Core) GetNodeInfo() nodeinfoPayload {
-	return c.nodeinfo.getNodeInfo()
+	return c.router.nodeinfo.getNodeInfo()
 }
 
 // Sets the nodeinfo.
 func (c *Core) SetNodeInfo(nodeinfo interface{}, nodeinfoprivacy bool) {
-	c.nodeinfo.setNodeInfo(nodeinfo, nodeinfoprivacy)
+	c.router.nodeinfo.setNodeInfo(nodeinfo, nodeinfoprivacy)
 }
 
 // Sets the output logger of the Yggdrasil node after startup. This may be
@@ -270,13 +311,6 @@ func (c *Core) AddPeer(addr string, sintf string) error {
 	return c.admin.addPeer(addr, sintf)
 }
 
-// Adds an expression to select multicast interfaces for peer discovery. This
-// should be done before calling Start. This function can be called multiple
-// times to add multiple search expressions.
-func (c *Core) AddMulticastInterfaceExpr(expr *regexp.Regexp) {
-	c.ifceExpr = append(c.ifceExpr, expr)
-}
-
 // Adds an allowed public key. This allow peerings to be restricted only to
 // keys that you have selected.
 func (c *Core) AddAllowedEncryptionPublicKey(boxStr string) error {

src/yggdrasil/debug.go

@@ -16,6 +16,7 @@ import "fmt"
 import "net"
 import "log"
 import "regexp"
+import "encoding/hex"
 
 import _ "net/http/pprof"
 import "net/http"
@@ -23,6 +24,7 @@ import "runtime"
 import "os"
 
 import "github.com/yggdrasil-network/yggdrasil-go/src/address"
+import "github.com/yggdrasil-network/yggdrasil-go/src/config"
 import "github.com/yggdrasil-network/yggdrasil-go/src/crypto"
 import "github.com/yggdrasil-network/yggdrasil-go/src/defaults"
 
@@ -52,7 +54,17 @@ func StartProfiler(log *log.Logger) error {
 func (c *Core) Init() {
 	bpub, bpriv := crypto.NewBoxKeys()
 	spub, spriv := crypto.NewSigKeys()
-	c.init(bpub, bpriv, spub, spriv)
+	hbpub := hex.EncodeToString(bpub[:])
+	hbpriv := hex.EncodeToString(bpriv[:])
+	hspub := hex.EncodeToString(spub[:])
+	hspriv := hex.EncodeToString(spriv[:])
+	c.config = config.NodeConfig{
+		EncryptionPublicKey:  hbpub,
+		EncryptionPrivateKey: hbpriv,
+		SigningPublicKey:     hspub,
+		SigningPrivateKey:    hspriv,
+	}
+	c.init( /*bpub, bpriv, spub, spriv*/ )
 	c.switchTable.start()
 	c.router.start()
 }
@@ -350,7 +362,7 @@ func (c *Core) DEBUG_init(bpub []byte,
 	bpriv []byte,
 	spub []byte,
 	spriv []byte) {
-	var boxPub crypto.BoxPubKey
+	/*var boxPub crypto.BoxPubKey
 	var boxPriv crypto.BoxPrivKey
 	var sigPub crypto.SigPubKey
 	var sigPriv crypto.SigPrivKey
@@ -358,7 +370,18 @@ func (c *Core) DEBUG_init(bpub []byte,
 	copy(boxPriv[:], bpriv)
 	copy(sigPub[:], spub)
 	copy(sigPriv[:], spriv)
-	c.init(&boxPub, &boxPriv, &sigPub, &sigPriv)
+	c.init(&boxPub, &boxPriv, &sigPub, &sigPriv)*/
+	hbpub := hex.EncodeToString(bpub[:])
+	hbpriv := hex.EncodeToString(bpriv[:])
+	hspub := hex.EncodeToString(spub[:])
+	hspriv := hex.EncodeToString(spriv[:])
+	c.config = config.NodeConfig{
+		EncryptionPublicKey:  hbpub,
+		EncryptionPrivateKey: hbpriv,
+		SigningPublicKey:     hspub,
+		SigningPrivateKey:    hspriv,
+	}
+	c.init( /*bpub, bpriv, spub, spriv*/ )
 
 	if err := c.router.start(); err != nil {
 		panic(err)
@@ -427,7 +450,8 @@ func (c *Core) DEBUG_addSOCKSConn(socksaddr, peeraddr string) {
 
 //*
 func (c *Core) DEBUG_setupAndStartGlobalTCPInterface(addrport string) {
-	if err := c.tcp.init(c, addrport, 0); err != nil {
+	c.config.Listen = addrport
+	if err := c.tcp.init(c /*, addrport, 0*/); err != nil {
 		c.log.Println("Failed to start TCP interface:", err)
 		panic(err)
 	}
@@ -474,7 +498,8 @@ func (c *Core) DEBUG_addKCPConn(saddr string) {
 
 func (c *Core) DEBUG_setupAndStartAdminInterface(addrport string) {
 	a := admin{}
-	a.init(c, addrport)
+	c.config.AdminListen = addrport
+	a.init(c /*, addrport*/)
 	c.admin = a
 }
 
@@ -492,7 +517,7 @@ func (c *Core) DEBUG_setLogger(log *log.Logger) {
 }
 
 func (c *Core) DEBUG_setIfceExpr(expr *regexp.Regexp) {
-	c.ifceExpr = append(c.ifceExpr, expr)
+	c.log.Println("DEBUG_setIfceExpr no longer implemented")
 }
 
 func (c *Core) DEBUG_addAllowedEncryptionPublicKey(boxStr string) {

src/yggdrasil/dht.go

@@ -66,6 +66,7 @@ type dhtReqKey struct {
 // The main DHT struct.
 type dht struct {
 	core        *Core
+	reconfigure chan chan error
 	nodeID      crypto.NodeID
 	peers       chan *dhtInfo                  // other goroutines put incoming dht updates here
 	reqs        map[dhtReqKey]time.Time        // Keeps track of recent outstanding requests
@@ -78,6 +79,13 @@ type dht struct {
 // Initializes the DHT.
 func (t *dht) init(c *Core) {
 	t.core = c
+	t.reconfigure = make(chan chan error, 1)
+	go func() {
+		for {
+			e := <-t.reconfigure
+			e <- nil
+		}
+	}()
 	t.nodeID = *t.core.GetNodeID()
 	t.peers = make(chan *dhtInfo, 1024)
 	t.callbacks = make(map[dhtReqKey]dht_callbackInfo)

src/yggdrasil/multicast.go

@@ -4,6 +4,8 @@ import (
 	"context"
 	"fmt"
 	"net"
+	"regexp"
+	"sync"
 	"time"
 
 	"golang.org/x/net/ipv6"
@@ -11,23 +13,34 @@ import (
 
 type multicast struct {
 	core        *Core
+	reconfigure chan chan error
 	sock        *ipv6.PacketConn
 	groupAddr   string
+	myAddr      *net.TCPAddr
+	myAddrMutex sync.RWMutex
 }
 
 func (m *multicast) init(core *Core) {
 	m.core = core
+	m.reconfigure = make(chan chan error, 1)
+	go func() {
+		for {
+			e := <-m.reconfigure
+			m.myAddrMutex.Lock()
+			m.myAddr = m.core.tcp.getAddr()
+			m.myAddrMutex.Unlock()
+			e <- nil
+		}
+	}()
 	m.groupAddr = "[ff02::114]:9001"
 	// Check if we've been given any expressions
-	if len(m.core.ifceExpr) == 0 {
+	if count := len(m.interfaces()); count != 0 {
-		return
+		m.core.log.Println("Found", count, "multicast interface(s)")
 	}
-	// Ask the system for network interfaces
-	m.core.log.Println("Found", len(m.interfaces()), "multicast interface(s)")
 }
 
 func (m *multicast) start() error {
-	if len(m.core.ifceExpr) == 0 {
+	if len(m.interfaces()) == 0 {
 		m.core.log.Println("Multicast discovery is disabled")
 	} else {
 		m.core.log.Println("Multicast discovery is enabled")
@@ -55,6 +68,10 @@ func (m *multicast) start() error {
 }
 
 func (m *multicast) interfaces() []net.Interface {
+	// Get interface expressions from config
+	m.core.configMutex.RLock()
+	exprs := m.core.config.MulticastInterfaces
+	m.core.configMutex.RUnlock()
 	// Ask the system for network interfaces
 	var interfaces []net.Interface
 	allifaces, err := net.Interfaces()
@@ -75,8 +92,12 @@ func (m *multicast) interfaces() []net.Interface {
 			// Ignore point-to-point interfaces
 			continue
 		}
-		for _, expr := range m.core.ifceExpr {
+		for _, expr := range exprs {
-			if expr.MatchString(iface.Name) {
+			e, err := regexp.Compile(expr)
+			if err != nil {
+				panic(err)
+			}
+			if e.MatchString(iface.Name) {
 				interfaces = append(interfaces, iface)
 			}
 		}
@@ -85,13 +106,14 @@ func (m *multicast) interfaces() []net.Interface {
 }
 
 func (m *multicast) announce() {
+	var anAddr net.TCPAddr
+	m.myAddrMutex.Lock()
+	m.myAddr = m.core.tcp.getAddr()
+	m.myAddrMutex.Unlock()
 	groupAddr, err := net.ResolveUDPAddr("udp6", m.groupAddr)
 	if err != nil {
 		panic(err)
 	}
-	var anAddr net.TCPAddr
-	myAddr := m.core.tcp.getAddr()
-	anAddr.Port = myAddr.Port
 	destAddr, err := net.ResolveUDPAddr("udp6", m.groupAddr)
 	if err != nil {
 		panic(err)
@@ -103,6 +125,9 @@ func (m *multicast) announce() {
 			if err != nil {
 				panic(err)
 			}
+			m.myAddrMutex.RLock()
+			anAddr.Port = m.myAddr.Port
+			m.myAddrMutex.RUnlock()
 			for _, addr := range addrs {
 				addrIP, _, _ := net.ParseCIDR(addr.String())
 				if addrIP.To4() != nil {

src/yggdrasil/nodeinfo.go

@@ -170,7 +170,7 @@ func (m *nodeinfo) sendNodeInfo(key crypto.BoxPubKey, coords []byte, isResponse
 	nodeinfo := nodeinfoReqRes{
 		SendCoords: table.self.getCoords(),
 		IsResponse: isResponse,
-		NodeInfo:   m.core.nodeinfo.getNodeInfo(),
+		NodeInfo:   m.getNodeInfo(),
 	}
 	bs := nodeinfo.encode()
 	shared := m.core.sessions.getSharedKey(&m.core.boxPriv, &key)

src/yggdrasil/peer.go

@@ -19,6 +19,7 @@ import (
 // In other cases, it's link protocol traffic used to build the spanning tree, in which case this checks signatures and passes the message along to the switch.
 type peers struct {
 	core                        *Core
+	reconfigure                 chan chan error
 	mutex                       sync.Mutex   // Synchronize writes to atomic
 	ports                       atomic.Value //map[switchPort]*peer, use CoW semantics
 	authMutex                   sync.RWMutex
@@ -31,6 +32,13 @@ func (ps *peers) init(c *Core) {
 	defer ps.mutex.Unlock()
 	ps.putPorts(make(map[switchPort]*peer))
 	ps.core = c
+	ps.reconfigure = make(chan chan error, 1)
+	go func() {
+		for {
+			e := <-ps.reconfigure
+			e <- nil
+		}
+	}()
 	ps.allowedEncryptionPublicKeys = make(map[crypto.BoxPubKey]struct{})
 }
 

src/yggdrasil/router.go

@@ -38,6 +38,7 @@ import (
 // The router's mainLoop goroutine is responsible for managing all information related to the dht, searches, and crypto sessions.
 type router struct {
 	core        *Core
+	reconfigure chan chan error
 	addr        address.Address
 	subnet      address.Subnet
 	in          <-chan []byte          // packets we received from the network, link to peer's "out"
@@ -50,6 +51,7 @@ type router struct {
 	reset       chan struct{}          // signal that coords changed (re-init sessions/dht)
 	admin       chan func()            // pass a lambda for the admin socket to query stuff
 	cryptokey   cryptokey
+	nodeinfo    nodeinfo
 }
 
 // Packet and session info, used to check that the packet matches a valid IP range or CKR prefix before sending to the tun.
@@ -61,6 +63,7 @@ type router_recvPacket struct {
 // Initializes the router struct, which includes setting up channels to/from the tun/tap.
 func (r *router) init(core *Core) {
 	r.core = core
+	r.reconfigure = make(chan chan error, 1)
 	r.addr = *address.AddrForNodeID(&r.core.dht.nodeID)
 	r.subnet = *address.SubnetForNodeID(&r.core.dht.nodeID)
 	in := make(chan []byte, 32) // TODO something better than this...
@@ -83,6 +86,9 @@ func (r *router) init(core *Core) {
 	r.send = send
 	r.reset = make(chan struct{}, 1)
 	r.admin = make(chan func(), 32)
+	r.core.configMutex.RLock()
+	r.nodeinfo.setNodeInfo(r.core.config.NodeInfo, r.core.config.NodeInfoPrivacy)
+	r.core.configMutex.RUnlock()
 	r.cryptokey.init(r.core)
 	r.tun.init(r.core, send, recv)
 }
@@ -124,6 +130,10 @@ func (r *router) mainLoop() {
 			}
 		case f := <-r.admin:
 			f()
+		case e := <-r.reconfigure:
+			r.core.configMutex.RLock()
+			e <- r.nodeinfo.setNodeInfo(r.core.config.NodeInfo, r.core.config.NodeInfoPrivacy)
+			r.core.configMutex.RUnlock()
 		}
 	}
 }
@@ -463,7 +473,7 @@ func (r *router) handleNodeInfo(bs []byte, fromKey *crypto.BoxPubKey) {
 		return
 	}
 	req.SendPermPub = *fromKey
-	r.core.nodeinfo.handleNodeInfo(&req)
+	r.nodeinfo.handleNodeInfo(&req)
 }
 
 // Passed a function to call.

src/yggdrasil/search.go

@@ -43,12 +43,20 @@ type searchInfo struct {
 // This stores a map of active searches.
 type searches struct {
 	core        *Core
+	reconfigure chan chan error
 	searches    map[crypto.NodeID]*searchInfo
 }
 
 // Intializes the searches struct.
 func (s *searches) init(core *Core) {
 	s.core = core
+	s.reconfigure = make(chan chan error, 1)
+	go func() {
+		for {
+			e := <-s.reconfigure
+			e <- nil
+		}
+	}()
 	s.searches = make(map[crypto.NodeID]*searchInfo)
 }
 

src/yggdrasil/session.go

@@ -7,6 +7,7 @@ package yggdrasil
 import (
 	"bytes"
 	"encoding/hex"
+	"sync"
 	"time"
 
 	"github.com/yggdrasil-network/yggdrasil-go/src/address"
@@ -18,6 +19,7 @@ import (
 // This includes coords, permanent and ephemeral keys, handles and nonces, various sorts of timing information for timeout and maintenance, and some metadata for the admin API.
 type sessionInfo struct {
 	core         *Core
+	reconfigure  chan chan error
 	theirAddr    address.Address
 	theirSubnet  address.Subnet
 	theirPermPub crypto.BoxPubKey
@@ -101,6 +103,7 @@ func (s *sessionInfo) timedout() bool {
 // Additionally, stores maps of address/subnet onto keys, and keys onto handles.
 type sessions struct {
 	core        *Core
+	reconfigure chan chan error
 	lastCleanup time.Time
 	// Maps known permanent keys to their shared key, used by DHT a lot
 	permShared map[crypto.BoxPubKey]*crypto.BoxSharedKey
@@ -113,6 +116,7 @@ type sessions struct {
 	addrToPerm   map[address.Address]*crypto.BoxPubKey
 	subnetToPerm map[address.Subnet]*crypto.BoxPubKey
 	// Options from the session firewall
+	sessionFirewallMutex                sync.RWMutex
 	sessionFirewallEnabled              bool
 	sessionFirewallAllowsDirect         bool
 	sessionFirewallAllowsRemote         bool
@@ -124,6 +128,24 @@ type sessions struct {
 // Initializes the session struct.
 func (ss *sessions) init(core *Core) {
 	ss.core = core
+	ss.reconfigure = make(chan chan error, 1)
+	go func() {
+		for {
+			e := <-ss.reconfigure
+			responses := make(map[crypto.Handle]chan error)
+			for index, session := range ss.sinfos {
+				responses[index] = make(chan error)
+				session.reconfigure <- responses[index]
+			}
+			for _, response := range responses {
+				if err := <-response; err != nil {
+					e <- err
+					continue
+				}
+			}
+			e <- nil
+		}
+	}()
 	ss.permShared = make(map[crypto.BoxPubKey]*crypto.BoxSharedKey)
 	ss.sinfos = make(map[crypto.Handle]*sessionInfo)
 	ss.byMySes = make(map[crypto.BoxPubKey]*crypto.Handle)
@@ -135,12 +157,16 @@ func (ss *sessions) init(core *Core) {
 
 // Enable or disable the session firewall
 func (ss *sessions) setSessionFirewallState(enabled bool) {
+	ss.sessionFirewallMutex.Lock()
+	defer ss.sessionFirewallMutex.Unlock()
 	ss.sessionFirewallEnabled = enabled
 }
 
 // Set the session firewall defaults (first parameter is whether to allow
 // sessions from direct peers, second is whether to allow from remote nodes).
 func (ss *sessions) setSessionFirewallDefaults(allowsDirect bool, allowsRemote bool, alwaysAllowsOutbound bool) {
+	ss.sessionFirewallMutex.Lock()
+	defer ss.sessionFirewallMutex.Unlock()
 	ss.sessionFirewallAllowsDirect = allowsDirect
 	ss.sessionFirewallAllowsRemote = allowsRemote
 	ss.sessionFirewallAlwaysAllowsOutbound = alwaysAllowsOutbound
@@ -148,17 +174,24 @@ func (ss *sessions) setSessionFirewallDefaults(allowsDirect bool, allowsRemote b
 
 // Set the session firewall whitelist - nodes always allowed to open sessions.
 func (ss *sessions) setSessionFirewallWhitelist(whitelist []string) {
+	ss.sessionFirewallMutex.Lock()
+	defer ss.sessionFirewallMutex.Unlock()
 	ss.sessionFirewallWhitelist = whitelist
 }
 
 // Set the session firewall blacklist - nodes never allowed to open sessions.
 func (ss *sessions) setSessionFirewallBlacklist(blacklist []string) {
+	ss.sessionFirewallMutex.Lock()
+	defer ss.sessionFirewallMutex.Unlock()
 	ss.sessionFirewallBlacklist = blacklist
 }
 
 // Determines whether the session with a given publickey is allowed based on
 // session firewall rules.
 func (ss *sessions) isSessionAllowed(pubkey *crypto.BoxPubKey, initiator bool) bool {
+	ss.sessionFirewallMutex.RLock()
+	defer ss.sessionFirewallMutex.RUnlock()
+
 	// Allow by default if the session firewall is disabled
 	if !ss.sessionFirewallEnabled {
 		return true
@@ -264,13 +297,12 @@ func (ss *sessions) getByTheirSubnet(snet *address.Subnet) (*sessionInfo, bool)
 // Creates a new session and lazily cleans up old/timedout existing sessions.
 // This includse initializing session info to sane defaults (e.g. lowest supported MTU).
 func (ss *sessions) createSession(theirPermKey *crypto.BoxPubKey) *sessionInfo {
-	if ss.sessionFirewallEnabled {
 	if !ss.isSessionAllowed(theirPermKey, true) {
 		return nil
 	}
-	}
 	sinfo := sessionInfo{}
 	sinfo.core = ss.core
+	sinfo.reconfigure = make(chan chan error, 1)
 	sinfo.theirPermPub = *theirPermKey
 	pub, priv := crypto.NewBoxKeys()
 	sinfo.mySesPub = *pub
@@ -442,11 +474,14 @@ func (ss *sessions) handlePing(ping *sessionPing) {
 	// Get the corresponding session (or create a new session)
 	sinfo, isIn := ss.getByTheirPerm(&ping.SendPermPub)
 	// Check the session firewall
+	ss.sessionFirewallMutex.RLock()
 	if !isIn && ss.sessionFirewallEnabled {
 		if !ss.isSessionAllowed(&ping.SendPermPub, false) {
+			ss.sessionFirewallMutex.RUnlock()
 			return
 		}
 	}
+	ss.sessionFirewallMutex.RUnlock()
 	if !isIn || sinfo.timedout() {
 		if isIn {
 			sinfo.close()
@@ -539,6 +574,8 @@ func (sinfo *sessionInfo) doWorker() {
 			} else {
 				return
 			}
+		case e := <-sinfo.reconfigure:
+			e <- nil
 		}
 	}
 }

src/yggdrasil/switch.go

@@ -162,6 +162,7 @@ type switchData struct {
 // All the information stored by the switch.
 type switchTable struct {
 	core              *Core
+	reconfigure       chan chan error
 	key               crypto.SigPubKey           // Our own key
 	time              time.Time                  // Time when locator.tstamp was last updated
 	drop              map[crypto.SigPubKey]int64 // Tstamp associated with a dropped root
@@ -181,11 +182,14 @@ type switchTable struct {
 const SwitchQueueTotalMinSize = 4 * 1024 * 1024
 
 // Initializes the switchTable struct.
-func (t *switchTable) init(core *Core, key crypto.SigPubKey) {
+func (t *switchTable) init(core *Core) {
 	now := time.Now()
 	t.core = core
-	t.key = key
+	t.reconfigure = make(chan chan error, 1)
-	locator := switchLocator{root: key, tstamp: now.Unix()}
+	t.core.configMutex.RLock()
+	t.key = t.core.sigPub
+	t.core.configMutex.RUnlock()
+	locator := switchLocator{root: t.key, tstamp: now.Unix()}
 	peers := make(map[switchPort]peerInfo)
 	t.data = switchData{locator: locator, peers: peers}
 	t.updater.Store(&sync.Once{})
@@ -808,6 +812,8 @@ func (t *switchTable) doWorker() {
 			}
 		case f := <-t.admin:
 			f()
+		case e := <-t.reconfigure:
+			e <- nil
 		}
 	}
 }

src/yggdrasil/tcp.go

@@ -39,8 +39,11 @@ const tcp_ping_interval = (default_tcp_timeout * 2 / 3)
 // The TCP listener and information about active TCP connections, to avoid duplication.
 type tcpInterface struct {
 	core        *Core
+	reconfigure chan chan error
 	serv        net.Listener
+	serv_stop   chan bool
 	tcp_timeout time.Duration
+	tcp_addr    string
 	mutex       sync.Mutex // Protecting the below
 	calls       map[string]struct{}
 	conns       map[tcpInfo](chan struct{})
@@ -81,10 +84,37 @@ func (iface *tcpInterface) connectSOCKS(socksaddr, peeraddr string) {
 }
 
 // Initializes the struct.
-func (iface *tcpInterface) init(core *Core, addr string, readTimeout int32) (err error) {
+func (iface *tcpInterface) init(core *Core) (err error) {
 	iface.core = core
+	iface.serv_stop = make(chan bool, 1)
+	iface.reconfigure = make(chan chan error, 1)
+	go func() {
+		for {
+			e := <-iface.reconfigure
+			iface.core.configMutex.RLock()
+			updated := iface.core.config.Listen != iface.core.configOld.Listen
+			iface.core.configMutex.RUnlock()
+			if updated {
+				iface.serv_stop <- true
+				iface.serv.Close()
+				e <- iface.listen()
+			} else {
+				e <- nil
+			}
+		}
+	}()
+
+	return iface.listen()
+}
+
+func (iface *tcpInterface) listen() error {
+	var err error
+
+	iface.core.configMutex.RLock()
+	iface.tcp_addr = iface.core.config.Listen
+	iface.tcp_timeout = time.Duration(iface.core.config.ReadTimeout) * time.Millisecond
+	iface.core.configMutex.RUnlock()
 
-	iface.tcp_timeout = time.Duration(readTimeout) * time.Millisecond
 	if iface.tcp_timeout >= 0 && iface.tcp_timeout < default_tcp_timeout {
 		iface.tcp_timeout = default_tcp_timeout
 	}
@@ -93,11 +123,12 @@ func (iface *tcpInterface) init(core *Core, addr string, readTimeout int32) (err
 	lc := net.ListenConfig{
 		Control: iface.tcpContext,
 	}
-	iface.serv, err = lc.Listen(ctx, "tcp", addr)
+	iface.serv, err = lc.Listen(ctx, "tcp", iface.tcp_addr)
 	if err == nil {
 		iface.calls = make(map[string]struct{})
 		iface.conns = make(map[tcpInfo](chan struct{}))
 		go iface.listener()
+		return nil
 	}
 
 	return err
@@ -109,12 +140,38 @@ func (iface *tcpInterface) listener() {
 	iface.core.log.Println("Listening for TCP on:", iface.serv.Addr().String())
 	for {
 		sock, err := iface.serv.Accept()
+		if err != nil {
+			iface.core.log.Println("Failed to accept connection:", err)
+			return
+		}
+		select {
+		case <-iface.serv_stop:
+			iface.core.log.Println("Stopping listener")
+			return
+		default:
 			if err != nil {
 				panic(err)
 			}
 			go iface.handler(sock, true)
 		}
 	}
+}
+
+// Checks if we already have a connection to this node
+func (iface *tcpInterface) isAlreadyConnected(info tcpInfo) bool {
+	iface.mutex.Lock()
+	defer iface.mutex.Unlock()
+	_, isIn := iface.conns[info]
+	return isIn
+}
+
+// Checks if we already are calling this address
+func (iface *tcpInterface) isAlreadyCalling(saddr string) bool {
+	iface.mutex.Lock()
+	defer iface.mutex.Unlock()
+	_, isIn := iface.calls[saddr]
+	return isIn
+}
 
 // Checks if a connection already exists.
 // If not, it adds it to the list of active outgoing calls (to block future attempts) and dials the address.
@@ -127,11 +184,9 @@ func (iface *tcpInterface) call(saddr string, socksaddr *string, sintf string) {
 		if sintf != "" {
 			callname = fmt.Sprintf("%s/%s", saddr, sintf)
 		}
-		quit := false
+		if iface.isAlreadyCalling(saddr) {
-		iface.mutex.Lock()
+			return
-		if _, isIn := iface.calls[callname]; isIn {
+		}
-			quit = true
-		} else {
 		iface.calls[callname] = struct{}{}
 		defer func() {
 			// Block new calls for a little while, to mitigate livelock scenarios
@@ -141,11 +196,6 @@ func (iface *tcpInterface) call(saddr string, socksaddr *string, sintf string) {
 			delete(iface.calls, callname)
 			iface.mutex.Unlock()
 		}()
-		}
-		iface.mutex.Unlock()
-		if quit {
-			return
-		}
 		var conn net.Conn
 		var err error
 		if socksaddr != nil {
@@ -252,9 +302,19 @@ func (iface *tcpInterface) handler(sock net.Conn, incoming bool) {
 		// TODO? Block forever to prevent future connection attempts? suppress future messages about the same node?
 		return
 	}
+	remoteAddr, _, e1 := net.SplitHostPort(sock.RemoteAddr().String())
+	localAddr, _, e2 := net.SplitHostPort(sock.LocalAddr().String())
+	if e1 != nil || e2 != nil {
+		return
+	}
 	info := tcpInfo{ // used as a map key, so don't include ephemeral link key
 		box:        meta.box,
 		sig:        meta.sig,
+		localAddr:  localAddr,
+		remoteAddr: remoteAddr,
+	}
+	if iface.isAlreadyConnected(info) {
+		return
 	}
 	// Quit the parent call if this is a connection to ourself
 	equiv := func(k1, k2 []byte) bool {
@@ -265,14 +325,14 @@ func (iface *tcpInterface) handler(sock net.Conn, incoming bool) {
 		}
 		return true
 	}
-	if equiv(info.box[:], iface.core.boxPub[:]) {
+	if equiv(meta.box[:], iface.core.boxPub[:]) {
 		return
 	}
-	if equiv(info.sig[:], iface.core.sigPub[:]) {
+	if equiv(meta.sig[:], iface.core.sigPub[:]) {
 		return
 	}
 	// Check if we're authorized to connect to this key / IP
-	if incoming && !iface.core.peers.isAllowedEncryptionPublicKey(&info.box) {
+	if incoming && !iface.core.peers.isAllowedEncryptionPublicKey(&meta.box) {
 		// Allow unauthorized peers if they're link-local
 		raddrStr, _, _ := net.SplitHostPort(sock.RemoteAddr().String())
 		raddr := net.ParseIP(raddrStr)
@@ -281,15 +341,13 @@ func (iface *tcpInterface) handler(sock net.Conn, incoming bool) {
 		}
 	}
 	// Check if we already have a connection to this node, close and block if yes
-	info.localAddr, _, _ = net.SplitHostPort(sock.LocalAddr().String())
-	info.remoteAddr, _, _ = net.SplitHostPort(sock.RemoteAddr().String())
 	iface.mutex.Lock()
-	if blockChan, isIn := iface.conns[info]; isIn {
+	/*if blockChan, isIn := iface.conns[info]; isIn {
 		iface.mutex.Unlock()
 		sock.Close()
 		<-blockChan
 		return
-	}
+	}*/
 	blockChan := make(chan struct{})
 	iface.conns[info] = blockChan
 	iface.mutex.Unlock()
@@ -301,7 +359,7 @@ func (iface *tcpInterface) handler(sock net.Conn, incoming bool) {
 	}()
 	// Note that multiple connections to the same node are allowed
 	//  E.g. over different interfaces
-	p := iface.core.peers.newPeer(&info.box, &info.sig, crypto.GetSharedKey(myLinkPriv, &meta.link), sock.RemoteAddr().String())
+	p := iface.core.peers.newPeer(&meta.box, &meta.sig, crypto.GetSharedKey(myLinkPriv, &meta.link), sock.RemoteAddr().String())
 	p.linkOut = make(chan []byte, 1)
 	in := func(bs []byte) {
 		p.handlePacket(bs)
@@ -363,16 +421,16 @@ func (iface *tcpInterface) handler(sock net.Conn, incoming bool) {
 	}()
 	us, _, _ := net.SplitHostPort(sock.LocalAddr().String())
 	them, _, _ := net.SplitHostPort(sock.RemoteAddr().String())
-	themNodeID := crypto.GetNodeID(&info.box)
+	themNodeID := crypto.GetNodeID(&meta.box)
 	themAddr := address.AddrForNodeID(themNodeID)
 	themAddrString := net.IP(themAddr[:]).String()
 	themString := fmt.Sprintf("%s@%s", themAddrString, them)
-	iface.core.log.Println("Connected:", themString, "source", us)
+	iface.core.log.Printf("Connected: %s, source: %s", themString, us)
 	err = iface.reader(sock, in) // In this goroutine, because of defers
 	if err == nil {
-		iface.core.log.Println("Disconnected:", themString, "source", us)
+		iface.core.log.Printf("Disconnected: %s, source: %s", themString, us)
 	} else {
-		iface.core.log.Println("Disconnected:", themString, "source", us, "with error:", err)
+		iface.core.log.Printf("Disconnected: %s, source: %s, error: %s", themString, us, err)
 	}
 	return
 }

src/yggdrasil/tun.go

@@ -5,6 +5,8 @@ package yggdrasil
 import (
 	"bytes"
 	"errors"
+	"fmt"
+	"net"
 	"sync"
 	"time"
 
@@ -42,11 +44,33 @@ func getSupportedMTU(mtu int) int {
 func (tun *tunAdapter) init(core *Core, send chan<- []byte, recv <-chan []byte) {
 	tun.Adapter.init(core, send, recv)
 	tun.icmpv6.init(tun)
+	go func() {
+		for {
+			e := <-tun.reconfigure
+			tun.core.configMutex.RLock()
+			updated := tun.core.config.IfName != tun.core.configOld.IfName ||
+				tun.core.config.IfTAPMode != tun.core.configOld.IfTAPMode ||
+				tun.core.config.IfMTU != tun.core.configOld.IfMTU
+			tun.core.configMutex.RUnlock()
+			if updated {
+				tun.core.log.Println("Reconfiguring TUN/TAP is not supported yet")
+				e <- nil
+			} else {
+				e <- nil
+			}
+		}
+	}()
 }
 
 // Starts the setup process for the TUN/TAP adapter, and if successful, starts
 // the read/write goroutines to handle packets on that interface.
-func (tun *tunAdapter) start(ifname string, iftapmode bool, addr string, mtu int) error {
+func (tun *tunAdapter) start() error {
+	tun.core.configMutex.RLock()
+	ifname := tun.core.config.IfName
+	iftapmode := tun.core.config.IfTAPMode
+	addr := fmt.Sprintf("%s/%d", net.IP(tun.core.router.addr[:]).String(), 8*len(address.GetPrefix())-1)
+	mtu := tun.core.config.IfMTU
+	tun.core.configMutex.RUnlock()
 	if ifname != "none" {
 		if err := tun.setup(ifname, iftapmode, addr, mtu); err != nil {
 			return err