Fix merge conflict from develop

.circleci/config.yml

@@ -5,7 +5,7 @@ version: 2.1
 jobs:
   build-linux:
     docker:
-      - image: circleci/golang:1.12.7
+      - image: circleci/golang:1.13.3
 
     steps:
       - checkout
@@ -48,6 +48,7 @@ jobs:
               PKGARCH=mipsel sh contrib/deb/generate.sh && mv yggdrasil /tmp/upload/$CINAME-$CIVERSION-linux-mipsel && mv yggdrasilctl /tmp/upload/$CINAME-$CIVERSION-yggdrasilctl-linux-mipsel;
               PKGARCH=mips sh contrib/deb/generate.sh && mv yggdrasil /tmp/upload/$CINAME-$CIVERSION-linux-mips && mv yggdrasilctl /tmp/upload/$CINAME-$CIVERSION-yggdrasilctl-linux-mips;
               PKGARCH=armhf sh contrib/deb/generate.sh && mv yggdrasil /tmp/upload/$CINAME-$CIVERSION-linux-armhf && mv yggdrasilctl /tmp/upload/$CINAME-$CIVERSION-yggdrasilctl-linux-armhf;
+              PKGARCH=armel sh contrib/deb/generate.sh && mv yggdrasil /tmp/upload/$CINAME-$CIVERSION-linux-armel && mv yggdrasilctl /tmp/upload/$CINAME-$CIVERSION-yggdrasilctl-linux-armel;
               PKGARCH=arm64 sh contrib/deb/generate.sh && mv yggdrasil /tmp/upload/$CINAME-$CIVERSION-linux-arm64 && mv yggdrasilctl /tmp/upload/$CINAME-$CIVERSION-yggdrasilctl-linux-arm64;
               mv *.deb /tmp/upload/
 
@@ -105,11 +106,11 @@ jobs:
               echo -e "Host *\n\tStrictHostKeyChecking no\n" >> ~/.ssh/config
 
       - run:
-          name: Install Go 1.12.7
+          name: Install Go 1.13.3
           command: |
               cd /tmp
-              curl -LO https://dl.google.com/go/go1.12.7.darwin-amd64.pkg
+              curl -LO https://dl.google.com/go/go1.13.3.darwin-amd64.pkg
-              sudo installer -pkg /tmp/go1.12.7.darwin-amd64.pkg -target /
+              sudo installer -pkg /tmp/go1.13.3.darwin-amd64.pkg -target /
 
       #- run:
       #    name: Install Gomobile
@@ -145,7 +146,7 @@ jobs:
 
   build-other:
     docker:
-      - image: circleci/golang:1.12.7
+      - image: circleci/golang:1.13.3
 
     steps:
       - checkout

README.md

@@ -49,7 +49,7 @@ You may also find other platform-specific wrappers, scripts or tools in the
 If you want to build from source, as opposed to installing one of the pre-built
 packages:
 
-1. Install [Go](https://golang.org) (requires Go 1.12 or later)
+1. Install [Go](https://golang.org) (requires Go 1.13 or later)
 2. Clone this repository
 2. Run `./build`
 

contrib/systemd/yggdrasil.service

@@ -9,7 +9,7 @@ ProtectHome=true
 ProtectSystem=true
 SyslogIdentifier=yggdrasil
 CapabilityBoundSet=CAP_NET_ADMIN
-ExecStartPre=+/sbin/modprobe tun
+ExecStartPre=+-/sbin/modprobe tun
 ExecStartPre=/bin/sh -ec "if ! test -s /etc/yggdrasil.conf; \
                 then umask 077; \
                 yggdrasil -genconf > /etc/yggdrasil.conf; \

go.mod

@@ -1,19 +1,18 @@
 module github.com/yggdrasil-network/yggdrasil-go
 
+go 1.13
+
 require (
-	github.com/Arceliar/phony v0.0.0-20191005181740-21679e75e3f0
+	github.com/Arceliar/phony v0.0.0-20191006174943-d0c68492aca0
 	github.com/gologme/log v0.0.0-20181207131047-4e5d8ccb38e8
 	github.com/hashicorp/go-syslog v1.0.0
-	github.com/hjson/hjson-go v3.0.1-0.20190209023717-9147687966d9+incompatible
+	github.com/hjson/hjson-go v3.0.0+incompatible
 	github.com/kardianos/minwinsvc v0.0.0-20151122163309-cad6b2b879b0
 	github.com/mitchellh/mapstructure v1.1.2
 	github.com/songgao/packets v0.0.0-20160404182456-549a10cd4091
-	github.com/songgao/water v0.0.0-20190725173103-fd331bda3f4b // indirect
-	github.com/vishvananda/netlink v1.0.0
-	github.com/vishvananda/netns v0.0.0-20190625233234-7109fa855b0f // indirect
 	github.com/yggdrasil-network/water v0.0.0-20190812103929-c83fe40250f8
-	golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2
+	golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550
-	golang.org/x/net v0.0.0-20190813141303-74dc4d7220e7
+	golang.org/x/net v0.0.0-20191021144547-ec77196f6094
-	golang.org/x/sys v0.0.0-20190813064441-fde4db37ae7a
+	golang.org/x/sys v0.0.0-20191024073052-e66fe6eb8e0c
 	golang.org/x/text v0.3.2
 )

go.sum

@@ -1,35 +1,30 @@
-github.com/Arceliar/phony v0.0.0-20191005181740-21679e75e3f0 h1:IOFsvAMFkgnKfSQHxXTeqb1+ODFeR5px1HCHU86KF30=
+github.com/Arceliar/phony v0.0.0-20191006174943-d0c68492aca0 h1:p3puK8Sl2xK+2FnnIvY/C0N1aqJo2kbEsdAzU+Tnv48=
-github.com/Arceliar/phony v0.0.0-20191005181740-21679e75e3f0/go.mod h1:6Lkn+/zJilRMsKmbmG1RPoamiArC6HS73xbwRyp3UyI=
+github.com/Arceliar/phony v0.0.0-20191006174943-d0c68492aca0/go.mod h1:6Lkn+/zJilRMsKmbmG1RPoamiArC6HS73xbwRyp3UyI=
 github.com/gologme/log v0.0.0-20181207131047-4e5d8ccb38e8 h1:WD8iJ37bRNwvETMfVTusVSAi0WdXTpfNVGY2aHycNKY=
 github.com/gologme/log v0.0.0-20181207131047-4e5d8ccb38e8/go.mod h1:gq31gQ8wEHkR+WekdWsqDuf8pXTUZA9BnnzTuPz1Y9U=
 github.com/hashicorp/go-syslog v1.0.0 h1:KaodqZuhUoZereWVIYmpUgZysurB1kBLX2j0MwMrUAE=
 github.com/hashicorp/go-syslog v1.0.0/go.mod h1:qPfqrKkXGihmCqbJM2mZgkZGvKG1dFdvsLplgctolz4=
-github.com/hjson/hjson-go v3.0.1-0.20190209023717-9147687966d9+incompatible h1:bLQ2Ve+eW65id3b8xEMQiAwJT4qGZeywAEMLvXjznvw=
+github.com/hjson/hjson-go v3.0.0+incompatible h1:mc8olpIxqF8mrEx6ePJOD6wCCOkX7+JcrKgINcJES10=
-github.com/hjson/hjson-go v3.0.1-0.20190209023717-9147687966d9+incompatible/go.mod h1:qsetwF8NlsTsOTwZTApNlTCerV+b2GjYRRcIk4JMFio=
+github.com/hjson/hjson-go v3.0.0+incompatible/go.mod h1:qsetwF8NlsTsOTwZTApNlTCerV+b2GjYRRcIk4JMFio=
 github.com/kardianos/minwinsvc v0.0.0-20151122163309-cad6b2b879b0 h1:YnZmFjg0Nvk8851WTVWlqMC1ecJH07Ctz+Ezxx4u54g=
 github.com/kardianos/minwinsvc v0.0.0-20151122163309-cad6b2b879b0/go.mod h1:rUi0/YffDo1oXBOGn1KRq7Fr07LX48XEBecQnmwjsAo=
 github.com/mitchellh/mapstructure v1.1.2 h1:fmNYVwqnSfB9mZU6OS2O6GsXM+wcskZDuKQzvN1EDeE=
 github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=
 github.com/songgao/packets v0.0.0-20160404182456-549a10cd4091 h1:1zN6ImoqhSJhN8hGXFaJlSC8msLmIbX8bFqOfWLKw0w=
 github.com/songgao/packets v0.0.0-20160404182456-549a10cd4091/go.mod h1:N20Z5Y8oye9a7HmytmZ+tr8Q2vlP0tAHP13kTHzwvQY=
-github.com/songgao/water v0.0.0-20190725173103-fd331bda3f4b h1:+y4hCMc/WKsDbAPsOQZgBSaSZ26uh2afyaWeVg/3s/c=
-github.com/songgao/water v0.0.0-20190725173103-fd331bda3f4b/go.mod h1:P5HUIBuIWKbyjl083/loAegFkfbFNx5i2qEP4CNbm7E=
-github.com/vishvananda/netlink v1.0.0 h1:bqNY2lgheFIu1meHUFSH3d7vG93AFyqg3oGbJCOJgSM=
-github.com/vishvananda/netlink v1.0.0/go.mod h1:+SR5DhBJrl6ZM7CoCKvpw5BKroDKQ+PJqOg65H/2ktk=
-github.com/vishvananda/netns v0.0.0-20190625233234-7109fa855b0f h1:nBX3nTcmxEtHSERBJaIo1Qa26VwRaopnZmfDQUXsF4I=
-github.com/vishvananda/netns v0.0.0-20190625233234-7109fa855b0f/go.mod h1:ZjcWmFBXmLKZu9Nxj3WKYEafiSqer2rnvPr0en9UNpI=
 github.com/yggdrasil-network/water v0.0.0-20190812103929-c83fe40250f8 h1:YY9Pg2BEp0jeUVU60svTOaDr+fs1ySC9RbdC1Qc6wOw=
 github.com/yggdrasil-network/water v0.0.0-20190812103929-c83fe40250f8/go.mod h1:R0SBCsugm+Sf1katgTb2t7GXMm+nRIv43tM4VDZbaOs=
-golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2 h1:VklqNMn3ovrHsnt90PveolxSbWFaJdECFbxSq0Mqo2M=
 golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
-golang.org/x/net v0.0.0-20190813141303-74dc4d7220e7 h1:fHDIZ2oxGnUZRN6WgWFCbYBjH9uqVPRCUVUDhs0wnbA=
+golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550 h1:ObdrDkeb4kJdCP557AjRjq69pTHfNouLtWZG7j9rPN8=
-golang.org/x/net v0.0.0-20190813141303-74dc4d7220e7/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/crypto v0.0.0-20191011191535-87dc89f01550/go.mod h1:yigFU9vqHzYiE8UmvKecakEJjdnWj3jj499lnFckfCI=
+golang.org/x/net v0.0.0-20190404232315-eb5bcb51f2a3/go.mod h1:t9HGtf8HONx5eT2rtn7q6eTqICYqUVnKs3thJo3Qplg=
+golang.org/x/net v0.0.0-20191021144547-ec77196f6094 h1:5O4U9trLjNpuhpynaDsqwCk+Tw6seqJz1EbqbnzHrc8=
+golang.org/x/net v0.0.0-20191021144547-ec77196f6094/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
 golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
-golang.org/x/sys v0.0.0-20190813064441-fde4db37ae7a h1:aYOabOQFp6Vj6W1F80affTUvO9UxmJRx8K0gsfABByQ=
+golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
-golang.org/x/sys v0.0.0-20190813064441-fde4db37ae7a/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20191024073052-e66fe6eb8e0c h1:usSYQsGq37L8RjJc5eznJ/AbwBxn3QFFEVkWNPAejLs=
-golang.org/x/text v0.3.0 h1:g61tztE5qeGQ89tm6NTjjM9VPIm088od1l6aSorWRWg=
+golang.org/x/sys v0.0.0-20191024073052-e66fe6eb8e0c/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=
 golang.org/x/text v0.3.2 h1:tW2bmiBqwgJj/UpqtC8EpXEZVYOwU0yG4iWbprSVAcs=
 golang.org/x/text v0.3.2/go.mod h1:bEr9sfX3Q8Zfm5fL9x+3itogRgK3+ptLWKqgva+5dAk=
-golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e h1:FDhOuMEY4JVRztM/gsbk+IKUQ8kj74bxZrgw87eMMVc=
 golang.org/x/tools v0.0.0-20180917221912-90fa682c2a6e/go.mod h1:n7NCudcB/nEzxVGmLbDWY5pfWTLqBcC2KZ6jyYvM4mQ=

src/multicast/multicast.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"net"
 	"regexp"
+	"sync/atomic"
 	"time"
 
 	"github.com/Arceliar/phony"
@@ -28,7 +29,7 @@ type Multicast struct {
 	groupAddr       string
 	listeners       map[string]*listenerInfo
 	listenPort      uint16
-	isOpen          bool
+	isOpen          atomic.Value // bool
 	announcer       *time.Timer
 	platformhandler *time.Timer
 }
@@ -48,6 +49,7 @@ func (m *Multicast) Init(core *yggdrasil.Core, state *config.NodeState, log *log
 	current := m.config.GetCurrent()
 	m.listenPort = current.LinkLocalTCPPort
 	m.groupAddr = "[ff02::114]:9001"
+	m.isOpen.Store(false)
 	return nil
 }
 
@@ -55,12 +57,22 @@ func (m *Multicast) Init(core *yggdrasil.Core, state *config.NodeState, log *log
 // listen for multicast beacons from other hosts and will advertise multicast
 // beacons out to the network.
 func (m *Multicast) Start() error {
-	if len(m.config.GetCurrent().MulticastInterfaces) == 0 {
+	var err error
-		return fmt.Errorf("no MulticastInterfaces configured")
+	phony.Block(m, func() {
+		err = m._start()
+	})
+	m.log.Debugln("Started multicast module")
+	return err
+}
+
+func (m *Multicast) _start() error {
+	if m.IsStarted() {
+		return fmt.Errorf("multicast module is already started")
+	}
+	if len(m.config.GetCurrent().MulticastInterfaces) == 0 {
+		return nil
 	}
-
 	m.log.Infoln("Starting multicast module")
-
 	addr, err := net.ResolveUDPAddr("udp", m.groupAddr)
 	if err != nil {
 		return err
@@ -78,7 +90,7 @@ func (m *Multicast) Start() error {
 		// Windows can't set this flag, so we need to handle it in other ways
 	}
 
-	m.isOpen = true
+	m.isOpen.Store(true)
 	go m.listen()
 	m.Act(m, m.multicastStarted)
 	m.Act(m, m.announce)
@@ -88,13 +100,25 @@ func (m *Multicast) Start() error {
 
 // IsStarted returns true if the module has been started.
 func (m *Multicast) IsStarted() bool {
-	return m.isOpen
+	if m.isOpen.Load() == nil {
+		return false
+	}
+	return m.isOpen.Load().(bool)
 }
 
-// Stop is not implemented for multicast yet.
+// Stop stops the multicast module.
 func (m *Multicast) Stop() error {
+	var err error
+	phony.Block(m, func() {
+		err = m._stop()
+	})
+	m.log.Debugln("Stopped multicast module")
+	return nil
+}
+
+func (m *Multicast) _stop() error {
 	m.log.Infoln("Stopping multicast module")
-	m.isOpen = false
+	m.isOpen.Store(false)
 	if m.announcer != nil {
 		m.announcer.Stop()
 	}
@@ -113,17 +137,22 @@ func (m *Multicast) UpdateConfig(config *config.NodeConfig) {
 }
 
 func (m *Multicast) _updateConfig(config *config.NodeConfig) {
-	m.log.Debugln("Reloading multicast configuration...")
+	m.log.Infoln("Reloading multicast configuration...")
 	if m.IsStarted() {
 		if len(config.MulticastInterfaces) == 0 || config.LinkLocalTCPPort != m.listenPort {
-			m.Stop()
+			if err := m._stop(); err != nil {
+				m.log.Errorln("Error stopping multicast module:", err)
+			}
 		}
 	}
 	m.config.Replace(*config)
 	m.listenPort = config.LinkLocalTCPPort
 	if !m.IsStarted() && len(config.MulticastInterfaces) > 0 {
-		m.Start()
+		if err := m._start(); err != nil {
+			m.log.Errorln("Error starting multicast module:", err)
 		}
+	}
+	m.log.Debugln("Reloaded multicast configuration successfully")
 }
 
 // GetInterfaces returns the currently known/enabled multicast interfaces. It is
@@ -296,7 +325,7 @@ func (m *Multicast) listen() {
 	for {
 		nBytes, rcm, fromAddr, err := m.sock.ReadFrom(bs)
 		if err != nil {
-			if !m.isOpen {
+			if !m.IsStarted() {
 				return
 			}
 			panic(err)

src/yggdrasil/api.go

@@ -280,7 +280,14 @@ func (c *Core) ConnDialer() (*Dialer, error) {
 // "Listen" configuration item, e.g.
 // 		tcp://a.b.c.d:e
 func (c *Core) ListenTCP(uri string) (*TcpListener, error) {
-	return c.link.tcp.listen(uri)
+	return c.link.tcp.listen(uri, nil)
+}
+
+// ListenTLS starts a new TLS listener. The input URI should match that of the
+// "Listen" configuration item, e.g.
+// 		tls://a.b.c.d:e
+func (c *Core) ListenTLS(uri string) (*TcpListener, error) {
+	return c.link.tcp.listen(uri, c.link.tcp.tls.forListener)
 }
 
 // NodeID gets the node ID. This is derived from your router encryption keys.

src/yggdrasil/link.go

@@ -93,9 +93,11 @@ func (l *link) call(uri string, sintf string) error {
 	pathtokens := strings.Split(strings.Trim(u.Path, "/"), "/")
 	switch u.Scheme {
 	case "tcp":
-		l.tcp.call(u.Host, nil, sintf)
+		l.tcp.call(u.Host, nil, sintf, nil)
 	case "socks":
-		l.tcp.call(pathtokens[0], u.Host, sintf)
+		l.tcp.call(pathtokens[0], u.Host, sintf, nil)
+	case "tls":
+		l.tcp.call(u.Host, nil, sintf, l.tcp.tls.forDialer)
 	default:
 		return errors.New("unknown call scheme: " + u.Scheme)
 	}
@@ -109,7 +111,10 @@ func (l *link) listen(uri string) error {
 	}
 	switch u.Scheme {
 	case "tcp":
-		_, err := l.tcp.listen(u.Host)
+		_, err := l.tcp.listen(u.Host, nil)
+		return err
+	case "tls":
+		_, err := l.tcp.listen(u.Host, l.tcp.tls.forListener)
 		return err
 	default:
 		return errors.New("unknown listen scheme: " + u.Scheme)

src/yggdrasil/tcp.go

@@ -39,6 +39,7 @@ type tcp struct {
 	listeners map[string]*TcpListener
 	calls     map[string]struct{}
 	conns     map[linkInfo](chan struct{})
+	tls       tcptls
 }
 
 // TcpListener is a stoppable TCP listener interface. These are typically
@@ -47,9 +48,15 @@ type tcp struct {
 // multicast interfaces.
 type TcpListener struct {
 	Listener net.Listener
+	upgrade  *TcpUpgrade
 	stop     chan struct{}
 }
 
+type TcpUpgrade struct {
+	upgrade func(c net.Conn) (net.Conn, error)
+	name    string
+}
+
 func (l *TcpListener) Stop() {
 	defer func() { recover() }()
 	close(l.stop)
@@ -81,6 +88,7 @@ func (t *tcp) getAddr() *net.TCPAddr {
 // Initializes the struct.
 func (t *tcp) init(l *link) error {
 	t.link = l
+	t.tls.init(t)
 	t.mutex.Lock()
 	t.calls = make(map[string]struct{})
 	t.conns = make(map[linkInfo](chan struct{}))
@@ -90,13 +98,18 @@ func (t *tcp) init(l *link) error {
 	t.link.core.config.Mutex.RLock()
 	defer t.link.core.config.Mutex.RUnlock()
 	for _, listenaddr := range t.link.core.config.Current.Listen {
-		if listenaddr[:6] != "tcp://" {
+		switch listenaddr[:6] {
-			t.link.core.log.Errorln("Failed to add listener: listener", listenaddr, "is not correctly formatted, ignoring")
+		case "tcp://":
-			continue
+			if _, err := t.listen(listenaddr[6:], nil); err != nil {
-		}
-		if _, err := t.listen(listenaddr[6:]); err != nil {
 				return err
 			}
+		case "tls://":
+			if _, err := t.listen(listenaddr[6:], t.tls.forListener); err != nil {
+				return err
+			}
+		default:
+			t.link.core.log.Errorln("Failed to add listener: listener", listenaddr, "is not correctly formatted, ignoring")
+		}
 	}
 
 	return nil
@@ -119,18 +132,21 @@ func (t *tcp) reconfigure() {
 	t.link.core.config.Mutex.RUnlock()
 	if len(added) > 0 || len(deleted) > 0 {
 		for _, a := range added {
-			if a[:6] != "tcp://" {
+			switch a[:6] {
-				t.link.core.log.Errorln("Failed to add listener: listener", a, "is not correctly formatted, ignoring")
+			case "tcp://":
-				continue
+				if _, err := t.listen(a[6:], nil); err != nil {
-			}
-			if _, err := t.listen(a[6:]); err != nil {
 					t.link.core.log.Errorln("Error adding TCP", a[6:], "listener:", err)
-			} else {
+				}
-				t.link.core.log.Infoln("Started TCP listener:", a[6:])
+			case "tls://":
+				if _, err := t.listen(a[6:], t.tls.forListener); err != nil {
+					t.link.core.log.Errorln("Error adding TLS", a[6:], "listener:", err)
+				}
+			default:
+				t.link.core.log.Errorln("Failed to add listener: listener", a, "is not correctly formatted, ignoring")
 			}
 		}
 		for _, d := range deleted {
-			if d[:6] != "tcp://" {
+			if d[:6] != "tcp://" && d[:6] != "tls://" {
 				t.link.core.log.Errorln("Failed to delete listener: listener", d, "is not correctly formatted, ignoring")
 				continue
 			}
@@ -146,7 +162,7 @@ func (t *tcp) reconfigure() {
 	}
 }
 
-func (t *tcp) listen(listenaddr string) (*TcpListener, error) {
+func (t *tcp) listen(listenaddr string, upgrade *TcpUpgrade) (*TcpListener, error) {
 	var err error
 
 	ctx := context.Background()
@@ -157,6 +173,7 @@ func (t *tcp) listen(listenaddr string) (*TcpListener, error) {
 	if err == nil {
 		l := TcpListener{
 			Listener: listener,
+			upgrade:  upgrade,
 			stop:     make(chan struct{}),
 		}
 		t.waitgroup.Add(1)
@@ -204,7 +221,7 @@ func (t *tcp) listener(l *TcpListener, listenaddr string) {
 			return
 		}
 		t.waitgroup.Add(1)
-		go t.handler(sock, true, nil)
+		go t.handler(sock, true, nil, l.upgrade)
 	}
 }
 
@@ -222,11 +239,15 @@ func (t *tcp) startCalling(saddr string) bool {
 // If the dial is successful, it launches the handler.
 // When finished, it removes the outgoing call, so reconnection attempts can be made later.
 // This all happens in a separate goroutine that it spawns.
-func (t *tcp) call(saddr string, options interface{}, sintf string) {
+func (t *tcp) call(saddr string, options interface{}, sintf string, upgrade *TcpUpgrade) {
 	go func() {
 		callname := saddr
+		callproto := "TCP"
+		if upgrade != nil {
+			callproto = strings.ToUpper(upgrade.name)
+		}
 		if sintf != "" {
-			callname = fmt.Sprintf("%s/%s", saddr, sintf)
+			callname = fmt.Sprintf("%s/%s/%s", callproto, saddr, sintf)
 		}
 		if !t.startCalling(callname) {
 			return
@@ -261,7 +282,7 @@ func (t *tcp) call(saddr string, options interface{}, sintf string) {
 				return
 			}
 			t.waitgroup.Add(1)
-			t.handler(conn, false, saddr)
+			t.handler(conn, false, saddr, nil)
 		} else {
 			dst, err := net.ResolveTCPAddr("tcp", saddr)
 			if err != nil {
@@ -322,19 +343,29 @@ func (t *tcp) call(saddr string, options interface{}, sintf string) {
 			}
 			conn, err = dialer.Dial("tcp", dst.String())
 			if err != nil {
-				t.link.core.log.Debugln("Failed to dial TCP:", err)
+				t.link.core.log.Debugf("Failed to dial %s: %s", callproto, err)
 				return
 			}
 			t.waitgroup.Add(1)
-			t.handler(conn, false, nil)
+			t.handler(conn, false, nil, upgrade)
 		}
 	}()
 }
 
-func (t *tcp) handler(sock net.Conn, incoming bool, options interface{}) {
+func (t *tcp) handler(sock net.Conn, incoming bool, options interface{}, upgrade *TcpUpgrade) {
 	defer t.waitgroup.Done() // Happens after sock.close
 	defer sock.Close()
 	t.setExtraOptions(sock)
+	var upgraded bool
+	if upgrade != nil {
+		var err error
+		if sock, err = upgrade.upgrade(sock); err != nil {
+			t.link.core.log.Errorln("TCP handler upgrade failed:", err)
+			return
+		} else {
+			upgraded = true
+		}
+	}
 	stream := stream{}
 	stream.init(sock)
 	var name, proto, local, remote string
@@ -344,8 +375,13 @@ func (t *tcp) handler(sock net.Conn, incoming bool, options interface{}) {
 		local, _, _ = net.SplitHostPort(sock.LocalAddr().String())
 		remote, _, _ = net.SplitHostPort(socksaddr)
 	} else {
-		name = "tcp://" + sock.RemoteAddr().String()
+		if upgraded {
+			proto = upgrade.name
+			name = proto + "://" + sock.RemoteAddr().String()
+		} else {
 			proto = "tcp"
+			name = proto + "://" + sock.RemoteAddr().String()
+		}
 		local, _, _ = net.SplitHostPort(sock.LocalAddr().String())
 		remote, _, _ = net.SplitHostPort(sock.RemoteAddr().String())
 	}

src/yggdrasil/tls.go

@@ -0,0 +1,93 @@
+package yggdrasil
+
+import (
+	"bytes"
+	"crypto/ed25519"
+	"crypto/rand"
+	"crypto/tls"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/hex"
+	"encoding/pem"
+	"log"
+	"math/big"
+	"net"
+	"time"
+)
+
+type tcptls struct {
+	tcp         *tcp
+	config      *tls.Config
+	forDialer   *TcpUpgrade
+	forListener *TcpUpgrade
+}
+
+func (t *tcptls) init(tcp *tcp) {
+	t.tcp = tcp
+	t.forDialer = &TcpUpgrade{
+		upgrade: t.upgradeDialer,
+		name:    "tls",
+	}
+	t.forListener = &TcpUpgrade{
+		upgrade: t.upgradeListener,
+		name:    "tls",
+	}
+
+	edpriv := make(ed25519.PrivateKey, ed25519.PrivateKeySize)
+	copy(edpriv[:], tcp.link.core.sigPriv[:])
+
+	certBuf := &bytes.Buffer{}
+
+	// TODO: because NotAfter is finite, we should add some mechanism to regenerate the certificate and restart the listeners periodically for nodes with very high uptimes. Perhaps regenerate certs and restart listeners every few months or so.
+	pubtemp := x509.Certificate{
+		SerialNumber: big.NewInt(1),
+		Subject: pkix.Name{
+			CommonName: hex.EncodeToString(tcp.link.core.sigPub[:]),
+		},
+		NotBefore:             time.Now(),
+		NotAfter:              time.Now().Add(time.Hour * 24 * 365),
+		KeyUsage:              x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
+		ExtKeyUsage:           []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
+		BasicConstraintsValid: true,
+	}
+
+	derbytes, err := x509.CreateCertificate(rand.Reader, &pubtemp, &pubtemp, edpriv.Public(), edpriv)
+	if err != nil {
+		log.Fatalf("Failed to create certificate: %s", err)
+	}
+
+	if err := pem.Encode(certBuf, &pem.Block{Type: "CERTIFICATE", Bytes: derbytes}); err != nil {
+		panic("failed to encode certificate into PEM")
+	}
+
+	cpool := x509.NewCertPool()
+	cpool.AppendCertsFromPEM(derbytes)
+
+	t.config = &tls.Config{
+		RootCAs: cpool,
+		Certificates: []tls.Certificate{
+			{
+				Certificate: [][]byte{derbytes},
+				PrivateKey:  edpriv,
+			},
+		},
+		InsecureSkipVerify: true,
+		MinVersion:         tls.VersionTLS13,
+	}
+}
+
+func (t *tcptls) upgradeListener(c net.Conn) (net.Conn, error) {
+	conn := tls.Server(c, t.config)
+	if err := conn.Handshake(); err != nil {
+		return c, err
+	}
+	return conn, nil
+}
+
+func (t *tcptls) upgradeDialer(c net.Conn) (net.Conn, error) {
+	conn := tls.Client(c, t.config)
+	if err := conn.Handshake(); err != nil {
+		return c, err
+	}
+	return conn, nil
+}