make the main library reconfiguration more actor-friendly

src/yggdrasil/core.go

@@ -117,20 +117,21 @@ func (c *Core) UpdateConfig(config *config.NodeConfig) {
 
 	errors := 0
 
-	components := []chan chan error{
-		c.router.searches.reconfigure,
-		c.router.dht.reconfigure,
-		c.router.sessions.reconfigure,
+	// Each reconfigure function should pass any errors to the channel, then close it
+	components := []func(chan error){
+		c.link.reconfigure,
 		c.peers.reconfigure,
 		c.router.reconfigure,
+		c.router.dht.reconfigure,
+		c.router.searches.reconfigure,
+		c.router.sessions.reconfigure,
 		c.switchTable.reconfigure,
-		c.link.reconfigure,
 	}
 
 	for _, component := range components {
 		response := make(chan error)
-		component <- response
-		if err := <-response; err != nil {
+		go component(response)
+		for err := range response {
 			c.log.Errorln(err)
 			errors++
 		}

src/yggdrasil/dht.go

@@ -65,11 +65,10 @@ type dhtReqKey struct {
 
 // The main DHT struct.
 type dht struct {
-	router      *router
-	reconfigure chan chan error
-	nodeID      crypto.NodeID
-	reqs        map[dhtReqKey]time.Time          // Keeps track of recent outstanding requests
-	callbacks   map[dhtReqKey][]dht_callbackInfo // Search and admin lookup callbacks
+	router    *router
+	nodeID    crypto.NodeID
+	reqs      map[dhtReqKey]time.Time          // Keeps track of recent outstanding requests
+	callbacks map[dhtReqKey][]dht_callbackInfo // Search and admin lookup callbacks
 	// These next two could be replaced by a single linked list or similar...
 	table map[crypto.NodeID]*dhtInfo
 	imp   []*dhtInfo
@@ -78,18 +77,16 @@ type dht struct {
 // Initializes the DHT.
 func (t *dht) init(r *router) {
 	t.router = r
-	t.reconfigure = make(chan chan error, 1)
-	go func() {
-		for {
-			e := <-t.reconfigure
-			e <- nil
-		}
-	}()
 	t.nodeID = *t.router.core.NodeID()
 	t.callbacks = make(map[dhtReqKey][]dht_callbackInfo)
 	t.reset()
 }
 
+func (t *dht) reconfigure(e chan error) {
+	defer close(e)
+	// This is where reconfiguration would go, if we had anything to do
+}
+
 // Resets the DHT in response to coord changes.
 // This empties all info from the DHT and drops outstanding requests.
 func (t *dht) reset() {

src/yggdrasil/link.go

@@ -21,11 +21,10 @@ import (
 )
 
 type link struct {
-	core        *Core
-	reconfigure chan chan error
-	mutex       sync.RWMutex // protects interfaces below
-	interfaces  map[linkInfo]*linkInterface
-	tcp         tcp // TCP interface support
+	core       *Core
+	mutex      sync.RWMutex // protects interfaces below
+	interfaces map[linkInfo]*linkInterface
+	tcp        tcp // TCP interface support
 	// TODO timeout (to remove from switch), read from config.ReadTimeout
 }
 
@@ -61,7 +60,6 @@ func (l *link) init(c *Core) error {
 	l.core = c
 	l.mutex.Lock()
 	l.interfaces = make(map[linkInfo]*linkInterface)
-	l.reconfigure = make(chan chan error)
 	l.mutex.Unlock()
 
 	if err := l.tcp.init(l); err != nil {
@@ -69,22 +67,18 @@ func (l *link) init(c *Core) error {
 		return err
 	}
 
-	go func() {
-		for {
-			e := <-l.reconfigure
-			tcpresponse := make(chan error)
-			l.tcp.reconfigure <- tcpresponse
-			if err := <-tcpresponse; err != nil {
-				e <- err
-				continue
-			}
-			e <- nil
-		}
-	}()
-
 	return nil
 }
 
+func (l *link) reconfigure(e chan error) {
+	defer close(e)
+	tcpResponse := make(chan error)
+	go l.tcp.reconfigure(tcpResponse)
+	for err := range tcpResponse {
+		e <- err
+	}
+}
+
 func (l *link) call(uri string, sintf string) error {
 	u, err := url.Parse(uri)
 	if err != nil {

src/yggdrasil/peer.go

@@ -21,10 +21,9 @@ import (
 // In most cases, this involves passing the packet to the handler for outgoing traffic to another peer.
 // 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
+	core  *Core
+	mutex sync.Mutex   // Synchronize writes to atomic
+	ports atomic.Value //map[switchPort]*peer, use CoW semantics
 }
 
 // Initializes the peers struct.
@@ -33,13 +32,11 @@ 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
-		}
-	}()
+}
+
+func (ps *peers) reconfigure(e chan error) {
+	defer close(e)
+	// This is where reconfiguration would go, if we had anything to do
 }
 
 // Returns true if an incoming peer connection to a key is allowed, either

src/yggdrasil/router.go

@@ -35,24 +35,22 @@ import (
 )
 
 // The router struct has channels to/from the adapter device and a self peer (0), which is how messages are passed between this node and the peers/switch layer.
-// The router's mainLoop goroutine is responsible for managing all information related to the dht, searches, and crypto sessions.
+// The router's phony.Inbox goroutine is responsible for managing all information related to the dht, searches, and crypto sessions.
 type router struct {
 	phony.Inbox
-	core        *Core
-	reconfigure chan chan error
-	addr        address.Address
-	subnet      address.Subnet
-	out         func([]byte) // packets we're sending to the network, link to peer's "in"
-	dht         dht
-	nodeinfo    nodeinfo
-	searches    searches
-	sessions    sessions
+	core     *Core
+	addr     address.Address
+	subnet   address.Subnet
+	out      func([]byte) // packets we're sending to the network, link to peer's "in"
+	dht      dht
+	nodeinfo nodeinfo
+	searches searches
+	sessions sessions
 }
 
 // Initializes the router struct, which includes setting up channels to/from the adapter.
 func (r *router) init(core *Core) {
 	r.core = core
-	r.reconfigure = make(chan chan error, 1)
 	r.addr = *address.AddrForNodeID(&r.dht.nodeID)
 	r.subnet = *address.SubnetForNodeID(&r.dht.nodeID)
 	self := linkInterface{
@@ -75,10 +73,26 @@ func (r *router) init(core *Core) {
 	r.sessions.init(r)
 }
 
-// Starts the mainLoop goroutine.
+func (r *router) reconfigure(e chan error) {
+	defer close(e)
+	var errs []error
+	// Reconfigure the router
+	<-r.SyncExec(func() {
+		current := r.core.config.GetCurrent()
+		err := r.nodeinfo.setNodeInfo(current.NodeInfo, current.NodeInfoPrivacy)
+		if err != nil {
+			errs = append(errs, err)
+		}
+	})
+	for _, err := range errs {
+		e <- err
+	}
+}
+
+// Starts the tickerLoop goroutine.
 func (r *router) start() error {
 	r.core.log.Infoln("Starting router")
-	go r._mainLoop()
+	go r.tickerLoop()
 	return nil
 }
 
@@ -108,24 +122,17 @@ func (r *router) reset(from phony.Actor) {
 
 // TODO remove reconfigure so this is just a ticker loop
 // and then find something better than a ticker loop to schedule things...
-func (r *router) _mainLoop() {
+func (r *router) tickerLoop() {
 	ticker := time.NewTicker(time.Second)
 	defer ticker.Stop()
 	for {
-		select {
-		case <-ticker.C:
-			<-r.SyncExec(func() {
-				// Any periodic maintenance stuff goes here
-				r.core.switchTable.doMaintenance()
-				r.dht.doMaintenance()
-				r.sessions.cleanup()
-			})
-		case e := <-r.reconfigure:
-			<-r.SyncExec(func() {
-				current := r.core.config.GetCurrent()
-				e <- r.nodeinfo.setNodeInfo(current.NodeInfo, current.NodeInfoPrivacy)
-			})
-		}
+		<-ticker.C
+		<-r.SyncExec(func() {
+			// Any periodic maintenance stuff goes here
+			r.core.switchTable.doMaintenance()
+			r.dht.doMaintenance()
+			r.sessions.cleanup()
+		})
 	}
 }
 

src/yggdrasil/search.go

@@ -45,24 +45,21 @@ type searchInfo struct {
 
 // This stores a map of active searches.
 type searches struct {
-	router      *router
-	reconfigure chan chan error
-	searches    map[crypto.NodeID]*searchInfo
+	router   *router
+	searches map[crypto.NodeID]*searchInfo
 }
 
 // Initializes the searches struct.
 func (s *searches) init(r *router) {
 	s.router = r
-	s.reconfigure = make(chan chan error, 1)
-	go func() {
-		for {
-			e := <-s.reconfigure
-			e <- nil
-		}
-	}()
 	s.searches = make(map[crypto.NodeID]*searchInfo)
 }
 
+func (s *searches) reconfigure(e chan error) {
+	defer close(e)
+	// This is where reconfiguration would go, if we had anything to do
+}
+
 // Creates a new search info, adds it to the searches struct, and returns a pointer to the info.
 func (s *searches) createSearch(dest *crypto.NodeID, mask *crypto.NodeID, callback func(*sessionInfo, error)) *searchInfo {
 	info := searchInfo{

src/yggdrasil/session.go

@@ -40,7 +40,6 @@ func (h nonceHeap) peek() *crypto.BoxNonce { return &h[0] }
 type sessionInfo struct {
 	phony.Inbox                                  // Protects all of the below, use it any time you read/change the contents of a session
 	sessions       *sessions                     //
-	reconfigure    chan chan error               //
 	theirAddr      address.Address               //
 	theirSubnet    address.Subnet                //
 	theirPermPub   crypto.BoxPubKey              //
@@ -74,6 +73,11 @@ type sessionInfo struct {
 	callbacks      []chan func()                 // Finished work from crypto workers
 }
 
+func (sinfo *sessionInfo) reconfigure(e chan error) {
+	defer close(e)
+	// This is where reconfiguration would go, if we had anything to do
+}
+
 // TODO remove this, call SyncExec directly
 func (sinfo *sessionInfo) doFunc(f func()) {
 	<-sinfo.SyncExec(f)
@@ -140,7 +144,6 @@ type sessions struct {
 	router           *router
 	listener         *Listener
 	listenerMutex    sync.Mutex
-	reconfigure      chan chan error
 	lastCleanup      time.Time
 	isAllowedHandler func(pubkey *crypto.BoxPubKey, initiator bool) bool // Returns true or false if session setup is allowed
 	isAllowedMutex   sync.RWMutex                                        // Protects the above
@@ -152,30 +155,28 @@ type sessions struct {
 // Initializes the session struct.
 func (ss *sessions) init(r *router) {
 	ss.router = r
-	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.byTheirPerm = make(map[crypto.BoxPubKey]*crypto.Handle)
 	ss.lastCleanup = time.Now()
 }
 
+func (ss *sessions) reconfigure(e chan error) {
+	defer close(e)
+	responses := make(map[crypto.Handle]chan error)
+	<-ss.router.SyncExec(func() {
+		for index, session := range ss.sinfos {
+			responses[index] = make(chan error)
+			go session.reconfigure(responses[index])
+		}
+	})
+	for _, response := range responses {
+		for err := range response {
+			e <- err
+		}
+	}
+}
+
 // 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 {
@@ -215,7 +216,6 @@ func (ss *sessions) createSession(theirPermKey *crypto.BoxPubKey) *sessionInfo {
 	}
 	sinfo := sessionInfo{}
 	sinfo.sessions = ss
-	sinfo.reconfigure = make(chan chan error, 1)
 	sinfo.theirPermPub = *theirPermKey
 	sinfo.sharedPermKey = *ss.getSharedKey(&ss.router.core.boxPriv, &sinfo.theirPermPub)
 	pub, priv := crypto.NewBoxKeys()

src/yggdrasil/switch.go

@@ -165,7 +165,6 @@ 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
@@ -186,7 +185,6 @@ const SwitchQueueTotalMinSize = 4 * 1024 * 1024
 func (t *switchTable) init(core *Core) {
 	now := time.Now()
 	t.core = core
-	t.reconfigure = make(chan chan error, 1)
 	t.key = t.core.sigPub
 	locator := switchLocator{root: t.key, tstamp: now.Unix()}
 	peers := make(map[switchPort]peerInfo)
@@ -201,6 +199,13 @@ func (t *switchTable) init(core *Core) {
 	})
 }
 
+func (t *switchTable) reconfigure(e chan error) {
+	go func() {
+		defer close(e)
+		// This is where reconfiguration would go, if we had anything useful to do.
+	}()
+}
+
 // Safely gets a copy of this node's locator.
 func (t *switchTable) getLocator() switchLocator {
 	t.mutex.RLock()
@@ -566,12 +571,7 @@ func (t *switchTable) getTable() lookupTable {
 // Starts the switch worker
 func (t *switchTable) start() error {
 	t.core.log.Infoln("Starting switch")
-	go func() {
-		// TODO find a better way to handle reconfiguration... and have the switch do something with the new configuration
-		for ch := range t.reconfigure {
-			ch <- nil
-		}
-	}()
+	// There's actually nothing to do to start it...
 	return nil
 }
 

src/yggdrasil/tcp.go

@@ -33,12 +33,11 @@ const tcp_ping_interval = (default_timeout * 2 / 3)
 
 // The TCP listener and information about active TCP connections, to avoid duplication.
 type tcp struct {
-	link        *link
-	reconfigure chan chan error
-	mutex       sync.Mutex // Protecting the below
-	listeners   map[string]*TcpListener
-	calls       map[string]struct{}
-	conns       map[linkInfo](chan struct{})
+	link      *link
+	mutex     sync.Mutex // Protecting the below
+	listeners map[string]*TcpListener
+	calls     map[string]struct{}
+	conns     map[linkInfo](chan struct{})
 }
 
 // TcpListener is a stoppable TCP listener interface. These are typically
@@ -76,49 +75,12 @@ func (t *tcp) getAddr() *net.TCPAddr {
 // Initializes the struct.
 func (t *tcp) init(l *link) error {
 	t.link = l
-	t.reconfigure = make(chan chan error, 1)
 	t.mutex.Lock()
 	t.calls = make(map[string]struct{})
 	t.conns = make(map[linkInfo](chan struct{}))
 	t.listeners = make(map[string]*TcpListener)
 	t.mutex.Unlock()
 
-	go func() {
-		for {
-			e := <-t.reconfigure
-			t.link.core.config.Mutex.RLock()
-			added := util.Difference(t.link.core.config.Current.Listen, t.link.core.config.Previous.Listen)
-			deleted := util.Difference(t.link.core.config.Previous.Listen, t.link.core.config.Current.Listen)
-			t.link.core.config.Mutex.RUnlock()
-			if len(added) > 0 || len(deleted) > 0 {
-				for _, a := range added {
-					if a[:6] != "tcp://" {
-						continue
-					}
-					if _, err := t.listen(a[6:]); err != nil {
-						e <- err
-						continue
-					}
-				}
-				for _, d := range deleted {
-					if d[:6] != "tcp://" {
-						continue
-					}
-					t.mutex.Lock()
-					if listener, ok := t.listeners[d[6:]]; ok {
-						t.mutex.Unlock()
-						listener.Stop <- true
-					} else {
-						t.mutex.Unlock()
-					}
-				}
-				e <- nil
-			} else {
-				e <- nil
-			}
-		}
-	}()
-
 	t.link.core.config.Mutex.RLock()
 	defer t.link.core.config.Mutex.RUnlock()
 	for _, listenaddr := range t.link.core.config.Current.Listen {
@@ -133,6 +95,36 @@ func (t *tcp) init(l *link) error {
 	return nil
 }
 
+func (t *tcp) reconfigure(e chan error) {
+	defer close(e)
+	t.link.core.config.Mutex.RLock()
+	added := util.Difference(t.link.core.config.Current.Listen, t.link.core.config.Previous.Listen)
+	deleted := util.Difference(t.link.core.config.Previous.Listen, t.link.core.config.Current.Listen)
+	t.link.core.config.Mutex.RUnlock()
+	if len(added) > 0 || len(deleted) > 0 {
+		for _, a := range added {
+			if a[:6] != "tcp://" {
+				continue
+			}
+			if _, err := t.listen(a[6:]); err != nil {
+				e <- err
+			}
+		}
+		for _, d := range deleted {
+			if d[:6] != "tcp://" {
+				continue
+			}
+			t.mutex.Lock()
+			if listener, ok := t.listeners[d[6:]]; ok {
+				t.mutex.Unlock()
+				listener.Stop <- true
+			} else {
+				t.mutex.Unlock()
+			}
+		}
+	}
+}
+
 func (t *tcp) listen(listenaddr string) (*TcpListener, error) {
 	var err error