From dc128121e57bd659ece83217b58a50d74a330ae0 Mon Sep 17 00:00:00 2001
From: Arceliar <Arceliar@users.noreply.github.com>
Date: Sat, 16 May 2020 09:25:57 -0500
Subject: [PATCH] update switch blockPeer/unblockPeer logic and dht reset when
 coords change

---
 src/yggdrasil/dht.go    | 13 +++++++------
 src/yggdrasil/link.go   |  1 +
 src/yggdrasil/peer.go   | 27 +++++++++++++--------------
 src/yggdrasil/switch.go | 20 +++++++++++++++++---
 4 files changed, 38 insertions(+), 23 deletions(-)

diff --git a/src/yggdrasil/dht.go b/src/yggdrasil/dht.go
index 56d03ed..f40ac3c 100644
--- a/src/yggdrasil/dht.go
+++ b/src/yggdrasil/dht.go
@@ -89,6 +89,11 @@ func (t *dht) reconfigure() {
 // Resets the DHT in response to coord changes.
 // This empties all info from the DHT and drops outstanding requests.
 func (t *dht) reset() {
+	for _, info := range t.table {
+		if t.isImportant(info) {
+			t.ping(info, nil)
+		}
+	}
 	t.reqs = make(map[dhtReqKey]time.Time)
 	t.table = make(map[crypto.NodeID]*dhtInfo)
 	t.imp = nil
@@ -144,12 +149,8 @@ func (t *dht) insert(info *dhtInfo) {
 
 // Insert a peer into the table if it hasn't been pinged lately, to keep peers from dropping
 func (t *dht) insertPeer(info *dhtInfo) {
-	oldInfo, isIn := t.table[*info.getNodeID()]
-	if !isIn || time.Since(oldInfo.recv) > dht_max_delay+30*time.Second {
-		// TODO? also check coords?
-		newInfo := *info // Insert a copy
-		t.insert(&newInfo)
-	}
+	t.insert(info)    // FIXME this resets timers / ping counts / etc, so it seems kind of dangerous
+	t.ping(info, nil) // This is a quick fix to the above, ping them immediately...
 }
 
 // Return true if first/second/third are (partially) ordered correctly.
diff --git a/src/yggdrasil/link.go b/src/yggdrasil/link.go
index 7f6b9b5..539d048 100644
--- a/src/yggdrasil/link.go
+++ b/src/yggdrasil/link.go
@@ -376,6 +376,7 @@ func (intf *linkInterface) notifyRead(size int) {
 		if size > 0 && intf.stallTimer == nil {
 			intf.stallTimer = time.AfterFunc(keepAliveTime, intf.notifyDoKeepAlive)
 		}
+		intf.link.core.switchTable.unblockPeer(intf, intf.peer.port)
 	})
 }
 
diff --git a/src/yggdrasil/peer.go b/src/yggdrasil/peer.go
index 801691a..31bba66 100644
--- a/src/yggdrasil/peer.go
+++ b/src/yggdrasil/peer.go
@@ -194,21 +194,20 @@ func (ps *peers) sendSwitchMsgs(from phony.Actor) {
 	})
 }
 
-// This must be launched in a separate goroutine by whatever sets up the peer struct.
-// It handles link protocol traffic.
-func (p *peer) start() {
-	var updateDHT func()
-	updateDHT = func() {
-		phony.Block(p, func() {
-			select {
-			case <-p.done:
-			default:
-				p._updateDHT()
-				time.AfterFunc(time.Second, updateDHT)
+func (ps *peers) updateDHT(from phony.Actor) {
+	ps.Act(from, func() {
+		for _, peer := range ps.ports {
+			p := peer
+			if p.port == 0 {
+				continue
 			}
-		})
-	}
-	updateDHT()
+			p.Act(ps, p._updateDHT)
+		}
+	})
+}
+
+// This must be launched in a separate goroutine by whatever sets up the peer struct.
+func (p *peer) start() {
 	// Just for good measure, immediately send a switch message to this peer when we start
 	p.Act(nil, p._sendSwitchMsg)
 }
diff --git a/src/yggdrasil/switch.go b/src/yggdrasil/switch.go
index 4f9044c..6ab9a02 100644
--- a/src/yggdrasil/switch.go
+++ b/src/yggdrasil/switch.go
@@ -239,11 +239,12 @@ func (t *switchTable) _cleanRoot() {
 func (t *switchTable) blockPeer(from phony.Actor, port switchPort) {
 	t.Act(from, func() {
 		peer, isIn := t.data.peers[port]
-		if !isIn {
+		if !isIn || peer.blocked {
 			return
 		}
 		peer.blocked = true
 		t.data.peers[port] = peer
+		t._updateTable()
 		if port != t.parent {
 			return
 		}
@@ -258,6 +259,18 @@ func (t *switchTable) blockPeer(from phony.Actor, port switchPort) {
 	})
 }
 
+func (t *switchTable) unblockPeer(from phony.Actor, port switchPort) {
+	t.Act(from, func() {
+		peer, isIn := t.data.peers[port]
+		if !isIn || !peer.blocked {
+			return
+		}
+		peer.blocked = false
+		t.data.peers[port] = peer
+		t._updateTable()
+	})
+}
+
 // Removes a peer.
 // Must be called by the router actor with a lambda that calls this.
 // If the removed peer was this node's parent, it immediately tries to find a new parent.
@@ -482,11 +495,12 @@ func (t *switchTable) _handleMsg(msg *switchMsg, fromPort switchPort, reprocessi
 		// The timestamp was updated, so we need to update locally and send to our peers.
 		updateRoot = true
 	}
+	// Note that we depend on the LIFO order of the stack of defers here...
 	if updateRoot {
 		if !equiv(&sender.locator, &t.data.locator) {
 			doUpdate = true
 			t.data.seq++
-			t.core.router.reset(nil)
+			defer t.core.router.reset(t)
 		}
 		if t.data.locator.tstamp != sender.locator.tstamp {
 			t.time = now
@@ -495,7 +509,7 @@ func (t *switchTable) _handleMsg(msg *switchMsg, fromPort switchPort, reprocessi
 		t.parent = sender.port
 		defer t.core.peers.sendSwitchMsgs(t)
 	}
-	if true || doUpdate {
+	if doUpdate {
 		defer t._updateTable()
 	}
 	return