From 25692420501e7252c2615382b8115d7119008eb2 Mon Sep 17 00:00:00 2001
From: Arceliar <Arceliar@users.noreply.github.com>
Date: Tue, 26 Feb 2019 21:07:56 -0600
Subject: [PATCH] fixes to linkInterface.handler()

---
 src/util/util.go      | 20 ++++++++++++++++++++
 src/yggdrasil/link.go | 11 ++++++++---
 2 files changed, 28 insertions(+), 3 deletions(-)

diff --git a/src/util/util.go b/src/util/util.go
index 45be3b19..df15ff2c 100644
--- a/src/util/util.go
+++ b/src/util/util.go
@@ -56,3 +56,23 @@ func TimerStop(t *time.Timer) bool {
 	}
 	return true
 }
+
+// Run a blocking function with a timeout.
+// Returns true if the function returns.
+// Returns false if the timer fires.
+// The blocked function remains blocked--the caller is responsible for somehow killing it.
+func FuncTimeout(f func(), timeout time.Duration) bool {
+	success := make(chan struct{})
+	go func() {
+		defer close(success)
+		f()
+	}()
+	timer := time.NewTimer(timeout)
+	defer TimerStop(timer)
+	select {
+	case <-success:
+		return true
+	case <-timer.C:
+		return false
+	}
+}
diff --git a/src/yggdrasil/link.go b/src/yggdrasil/link.go
index 443b5943..06020cd7 100644
--- a/src/yggdrasil/link.go
+++ b/src/yggdrasil/link.go
@@ -92,11 +92,16 @@ func (intf *linkInterface) handler() error {
 	meta.link = *myLinkPub
 	metaBytes := meta.encode()
 	// TODO timeouts on send/recv (goroutine for send/recv, channel select w/ timer)
-	err := intf.msgIO._sendMetaBytes(metaBytes)
+	var err error
+	if !util.FuncTimeout(func() { err = intf.msgIO._sendMetaBytes(metaBytes) }, 30*time.Second) {
+		return errors.New("timeout on metadata send")
+	}
 	if err != nil {
 		return err
 	}
-	metaBytes, err = intf.msgIO._recvMetaBytes()
+	if !util.FuncTimeout(func() { metaBytes, err = intf.msgIO._recvMetaBytes() }, 30*time.Second) {
+		return errors.New("timeout on metadata recv")
+	}
 	if err != nil {
 		return err
 	}
@@ -110,7 +115,7 @@ func (intf *linkInterface) handler() error {
 		return errors.New("failed to connect: wrong version")
 	}
 	// Check if we're authorized to connect to this key / IP
-	if !intf.force && !intf.link.core.peers.isAllowedEncryptionPublicKey(&meta.box) {
+	if !intf.incoming && !intf.force && !intf.link.core.peers.isAllowedEncryptionPublicKey(&meta.box) {
 		intf.link.core.log.Debugf("%s connection to %s forbidden: AllowedEncryptionPublicKeys does not contain key %s",
 			strings.ToUpper(intf.info.linkType), intf.info.remote, hex.EncodeToString(meta.box[:]))
 		intf.msgIO.close()