From f2e0abf1dc23544c7ce5cfb0bdd0fd46dc96ce1e Mon Sep 17 00:00:00 2001
From: Ethan Buchman <ethan@coinculture.info>
Date: Mon, 1 Jan 2018 20:21:11 -0500
Subject: [PATCH] p2p: reorder some checks in addPeer; add comments to NodeInfo

---
 p2p/peer.go   |  1 +
 p2p/switch.go | 20 ++++++++++----------
 p2p/types.go  | 14 +++++++-------
 3 files changed, 18 insertions(+), 17 deletions(-)

diff --git a/p2p/peer.go b/p2p/peer.go
index 91824dc8f..e2e73f0f3 100644
--- a/p2p/peer.go
+++ b/p2p/peer.go
@@ -304,6 +304,7 @@ func (p *peer) Set(key string, data interface{}) {
 }
 
 // Key returns the peer's id key.
+// TODO: call this ID
 func (p *peer) Key() string {
 	return p.nodeInfo.ListenAddr // XXX: should probably be PubKey.KeyString()
 }
diff --git a/p2p/switch.go b/p2p/switch.go
index fde216429..d4e3b3484 100644
--- a/p2p/switch.go
+++ b/p2p/switch.go
@@ -232,10 +232,15 @@ func (sw *Switch) OnStop() {
 // NOTE: If error is returned, caller is responsible for calling peer.CloseConn()
 func (sw *Switch) addPeer(peer *peer) error {
 
+	// Avoid self
+	if sw.nodeInfo.PubKey.Equals(peer.PubKey().Wrap()) {
+		return errors.New("Ignoring connection from self")
+	}
+
+	// Filter peer against white list
 	if err := sw.FilterConnByAddr(peer.Addr()); err != nil {
 		return err
 	}
-
 	if err := sw.FilterConnByPubKey(peer.PubKey()); err != nil {
 		return err
 	}
@@ -244,9 +249,10 @@ func (sw *Switch) addPeer(peer *peer) error {
 		return err
 	}
 
-	// Avoid self
-	if sw.nodeInfo.PubKey.Equals(peer.PubKey().Wrap()) {
-		return errors.New("Ignoring connection from self")
+	// Avoid duplicate
+	if sw.peers.Has(peer.Key()) {
+		return ErrSwitchDuplicatePeer
+
 	}
 
 	// Check version, chain id
@@ -254,12 +260,6 @@ func (sw *Switch) addPeer(peer *peer) error {
 		return err
 	}
 
-	// Check for duplicate peer
-	if sw.peers.Has(peer.Key()) {
-		return ErrSwitchDuplicatePeer
-
-	}
-
 	// Start peer
 	if sw.IsRunning() {
 		sw.startInitPeer(peer)
diff --git a/p2p/types.go b/p2p/types.go
index 63494d9cd..860132902 100644
--- a/p2p/types.go
+++ b/p2p/types.go
@@ -12,13 +12,13 @@ import (
 const maxNodeInfoSize = 10240 // 10Kb
 
 type NodeInfo struct {
-	PubKey     crypto.PubKey `json:"pub_key"`
-	Moniker    string        `json:"moniker"`
-	Network    string        `json:"network"`
-	RemoteAddr string        `json:"remote_addr"`
-	ListenAddr string        `json:"listen_addr"`
-	Version    string        `json:"version"` // major.minor.revision
-	Other      []string      `json:"other"`   // other application specific data
+	PubKey     crypto.PubKey `json:"pub_key"`     // authenticated pubkey
+	Moniker    string        `json:"moniker"`     // arbitrary moniker
+	Network    string        `json:"network"`     // network/chain ID
+	RemoteAddr string        `json:"remote_addr"` // address for the connection
+	ListenAddr string        `json:"listen_addr"` // accepting incoming
+	Version    string        `json:"version"`     // major.minor.revision
+	Other      []string      `json:"other"`       // other application specific data
 }
 
 // CONTRACT: two nodes are compatible if the major/minor versions match and network match