From b337228aa45436736640492b54cd64059f21a199 Mon Sep 17 00:00:00 2001
From: Arceliar <Arceliar@users.noreply.github.com>
Date: Sat, 24 Aug 2019 14:24:42 -0500
Subject: [PATCH] minor fixes to peer stuff

---
 src/yggdrasil/api.go   | 43 +++++++++++++++++++++++-------------------
 src/yggdrasil/debug.go |  2 +-
 src/yggdrasil/peer.go  | 20 +++++++++++++-------
 3 files changed, 38 insertions(+), 27 deletions(-)

diff --git a/src/yggdrasil/api.go b/src/yggdrasil/api.go
index f50c8ce..cbf232a 100644
--- a/src/yggdrasil/api.go
+++ b/src/yggdrasil/api.go
@@ -6,7 +6,6 @@ import (
 	"fmt"
 	"net"
 	"sort"
-	"sync/atomic"
 	"time"
 
 	"github.com/gologme/log"
@@ -106,15 +105,18 @@ func (c *Core) GetPeers() []Peer {
 	sort.Slice(ps, func(i, j int) bool { return ps[i] < ps[j] })
 	for _, port := range ps {
 		p := ports[port]
-		info := Peer{
-			Endpoint:   p.intf.name,
-			BytesSent:  atomic.LoadUint64(&p.bytesSent),
-			BytesRecvd: atomic.LoadUint64(&p.bytesRecvd),
-			Protocol:   p.intf.info.linkType,
-			Port:       uint64(port),
-			Uptime:     time.Since(p.firstSeen),
-		}
-		copy(info.PublicKey[:], p.box[:])
+		var info Peer
+		<-p.SyncExec(func() {
+			info = Peer{
+				Endpoint:   p.intf.name,
+				BytesSent:  p.bytesSent,
+				BytesRecvd: p.bytesRecvd,
+				Protocol:   p.intf.info.linkType,
+				Port:       uint64(port),
+				Uptime:     time.Since(p.firstSeen),
+			}
+			copy(info.PublicKey[:], p.box[:])
+		})
 		peers = append(peers, info)
 	}
 	return peers
@@ -135,15 +137,18 @@ func (c *Core) GetSwitchPeers() []SwitchPeer {
 			continue
 		}
 		coords := elem.locator.getCoords()
-		info := SwitchPeer{
-			Coords:     append([]uint64{}, wire_coordsBytestoUint64s(coords)...),
-			BytesSent:  atomic.LoadUint64(&peer.bytesSent),
-			BytesRecvd: atomic.LoadUint64(&peer.bytesRecvd),
-			Port:       uint64(elem.port),
-			Protocol:   peer.intf.info.linkType,
-			Endpoint:   peer.intf.info.remote,
-		}
-		copy(info.PublicKey[:], peer.box[:])
+		var info SwitchPeer
+		<-peer.SyncExec(func() {
+			info = SwitchPeer{
+				Coords:     append([]uint64{}, wire_coordsBytestoUint64s(coords)...),
+				BytesSent:  peer.bytesSent,
+				BytesRecvd: peer.bytesRecvd,
+				Port:       uint64(elem.port),
+				Protocol:   peer.intf.info.linkType,
+				Endpoint:   peer.intf.info.remote,
+			}
+			copy(info.PublicKey[:], peer.box[:])
+		})
 		switchpeers = append(switchpeers, info)
 	}
 	return switchpeers
diff --git a/src/yggdrasil/debug.go b/src/yggdrasil/debug.go
index d90bf1f..30eb874 100644
--- a/src/yggdrasil/debug.go
+++ b/src/yggdrasil/debug.go
@@ -576,7 +576,7 @@ func DEBUG_simLinkPeers(p, q *peer) {
 				default:
 				}
 				if len(packets) > 0 {
-					dest.handlePacket(packets[0])
+					<-dest.SyncExec(func() { dest._handlePacket(packets[0]) })
 					packets = packets[1:]
 					continue
 				}
diff --git a/src/yggdrasil/peer.go b/src/yggdrasil/peer.go
index f3af140..4bebc17 100644
--- a/src/yggdrasil/peer.go
+++ b/src/yggdrasil/peer.go
@@ -96,9 +96,6 @@ func (ps *peers) putPorts(ports map[switchPort]*peer) {
 
 // Information known about a peer, including thier box/sig keys, precomputed shared keys (static and ephemeral) and a handler for their outgoing traffic
 type peer struct {
-	bytesSent  uint64 // To track bandwidth usage for getPeers
-	bytesRecvd uint64 // To track bandwidth usage for getPeers
-	// BUG: sync/atomic, 32 bit platforms need the above to be the first element
 	phony.Actor
 	core       *Core
 	intf       *linkInterface
@@ -114,6 +111,9 @@ type peer struct {
 	out        func([][]byte)  // Set up by whatever created the peers struct, used to send packets to other nodes
 	done       (chan struct{}) // closed to exit the linkLoop
 	close      func()          // Called when a peer is removed, to close the underlying connection, or via admin api
+	// The below aren't actually useful internally, they're just gathered for getPeers statistics
+	bytesSent  uint64
+	bytesRecvd uint64
 }
 
 // Creates a new peer with the specified box, sig, and linkShared keys, using the lowest unoccupied port number.
@@ -217,7 +217,7 @@ func (p *peer) handlePacketFrom(from phony.IActor, packet []byte) {
 // Passes the packet to a handler for that packet type.
 func (p *peer) _handlePacket(packet []byte) {
 	// FIXME this is off by stream padding and msg length overhead, should be done in tcp.go
-	atomic.AddUint64(&p.bytesRecvd, uint64(len(packet)))
+	p.bytesRecvd += uint64(len(packet))
 	pType, pTypeLen := wire_decode_uint64(packet)
 	if pTypeLen == 0 {
 		return
@@ -259,10 +259,12 @@ func (p *peer) _sendPackets(packets [][]byte) {
 	for _, packet := range packets {
 		size += len(packet)
 	}
-	atomic.AddUint64(&p.bytesSent, uint64(size))
+	p.bytesSent += uint64(size)
 	p.out(packets)
 }
 
+var peerLinkOutHelper phony.Actor
+
 // This wraps the packet in the inner (ephemeral) and outer (permanent) crypto layers.
 // It sends it to p.linkOut, which bypasses the usual packet queues.
 func (p *peer) _sendLinkPacket(packet []byte) {
@@ -279,8 +281,12 @@ func (p *peer) _sendLinkPacket(packet []byte) {
 	}
 	packet = linkPacket.encode()
 	// TODO replace this with a message send if/when the link becomes an actor
-	// FIXME not 100% sure the channel send version is deadlock-free...
-	p.linkOut <- packet
+	peerLinkOutHelper.EnqueueFrom(nil, func() {
+		select {
+		case p.linkOut <- packet:
+		case <-p.done:
+		}
+	})
 }
 
 // Decrypts the outer (permanent) and inner (ephemeral) crypto layers on link traffic.