do session crypto work using the worker pool

src/yggdrasil/session.go

@@ -442,6 +442,7 @@ func (sinfo *sessionInfo) recvWorker() {
 	//  Since there's no reason for anywhere else in the session code to need to *read* it...
 	//  Only needs to be updated from the outside if a ping resets it...
 	//  That would get rid of the need to take a mutex for the sessionFunc
+	var callbacks []chan func()
 	doRecv := func(p *wire_trafficPacket) {
 		var bs []byte
 		var err error
@@ -459,31 +460,51 @@ func (sinfo *sessionInfo) recvWorker() {
 			return
 		}
 		var isOK bool
-		bs, isOK = crypto.BoxOpen(&k, p.Payload, &p.Nonce)
-		if !isOK {
-			util.PutBytes(bs)
-			return
-		}
-		sessionFunc = func() {
-			if k != sinfo.sharedSesKey || !sinfo.nonceIsOK(&p.Nonce) {
-				// The session updated in the mean time, so return an error
-				err = ConnError{errors.New("session updated during crypto operation"), false, true, false, 0}
-				return
+		ch := make(chan func(), 1)
+		poolFunc := func() {
+			bs, isOK = crypto.BoxOpen(&k, p.Payload, &p.Nonce)
+			callback := func() {
+				if !isOK {
+					util.PutBytes(bs)
+					return
+				}
+				sessionFunc = func() {
+					if k != sinfo.sharedSesKey || !sinfo.nonceIsOK(&p.Nonce) {
+						// The session updated in the mean time, so return an error
+						err = ConnError{errors.New("session updated during crypto operation"), false, true, false, 0}
+						return
+					}
+					sinfo.updateNonce(&p.Nonce)
+					sinfo.time = time.Now()
+					sinfo.bytesRecvd += uint64(len(bs))
+				}
+				sinfo.doFunc(sessionFunc)
+				if err != nil {
+					// Not sure what else to do with this packet, I guess just drop it
+					util.PutBytes(bs)
+				} else {
+					// Pass the packet to the buffer for Conn.Read
+					sinfo.recv <- bs
+				}
 			}
-			sinfo.updateNonce(&p.Nonce)
-			sinfo.time = time.Now()
-			sinfo.bytesRecvd += uint64(len(bs))
-		}
-		sinfo.doFunc(sessionFunc)
-		if err != nil {
-			// Not sure what else to do with this packet, I guess just drop it
-			util.PutBytes(bs)
-		} else {
-			// Pass the packet to the buffer for Conn.Read
-			sinfo.recv <- bs
+			ch <- callback
 		}
+		// Send to the worker and wait for it to finish
+		util.WorkerGo(poolFunc)
+		callbacks = append(callbacks, ch)
 	}
 	for {
+		for len(callbacks) > 0 {
+			select {
+			case f := <-callbacks[0]:
+				callbacks = callbacks[1:]
+				f()
+			case <-sinfo.cancel.Finished():
+				return
+			case p := <-sinfo.fromRouter:
+				doRecv(p)
+			}
+		}
 		select {
 		case <-sinfo.cancel.Finished():
 			return
@@ -496,6 +517,7 @@ func (sinfo *sessionInfo) recvWorker() {
 func (sinfo *sessionInfo) sendWorker() {
 	// TODO move info that this worker needs here, send updates via a channel
 	//  Otherwise we need to take a mutex to avoid races with update()
+	var callbacks []chan func()
 	doSend := func(bs []byte) {
 		var p wire_trafficPacket
 		var k crypto.BoxSharedKey
@@ -511,16 +533,34 @@ func (sinfo *sessionInfo) sendWorker() {
 		}
 		// Get the mutex-protected info needed to encrypt the packet
 		sinfo.doFunc(sessionFunc)
-		// Encrypt the packet
-		p.Payload, _ = crypto.BoxSeal(&k, bs, &p.Nonce)
-		packet := p.encode()
-		// Cleanup
-		util.PutBytes(bs)
-		util.PutBytes(p.Payload)
-		// Send the packet
-		sinfo.core.router.out(packet)
+		ch := make(chan func(), 1)
+		poolFunc := func() {
+			// Encrypt the packet
+			p.Payload, _ = crypto.BoxSeal(&k, bs, &p.Nonce)
+			packet := p.encode()
+			// Cleanup
+			util.PutBytes(bs)
+			util.PutBytes(p.Payload)
+			// The callback will send the packet
+			callback := func() { sinfo.core.router.out(packet) }
+			ch <- callback
+		}
+		// Send to the worker and wait for it to finish
+		util.WorkerGo(poolFunc)
+		callbacks = append(callbacks, ch)
 	}
 	for {
+		for len(callbacks) > 0 {
+			select {
+			case f := <-callbacks[0]:
+				callbacks = callbacks[1:]
+				f()
+			case <-sinfo.cancel.Finished():
+				return
+			case bs := <-sinfo.send:
+				doSend(bs)
+			}
+		}
 		select {
 		case <-sinfo.cancel.Finished():
 			return