From eefaed4b1ad9816841a56bd3f0bd1b64f2fe26d7 Mon Sep 17 00:00:00 2001
From: StephenButtolph <stephen@avalabs.org>
Date: Wed, 24 Jun 2020 11:41:22 -0400
Subject: [PATCH] added error reporting to nat.Map

---
 main/main.go   | 12 +++++++-----
 main/params.go |  4 ++--
 nat/nat.go     |  9 +++++++--
 3 files changed, 16 insertions(+), 9 deletions(-)

diff --git a/main/main.go b/main/main.go
index 71de46f..250c1e0 100644
--- a/main/main.go
+++ b/main/main.go
@@ -67,13 +67,15 @@ func main() {
 	mapper := nat.NewPortMapper(log, Config.Nat)
 	defer mapper.UnmapAllPorts()
 
-	Config.StakingIP.Port = mapper.Map("TCP", Config.StakingLocalPort, "gecko-staking") // Open staking port
-	if Config.HTTPHost != "127.0.0.1" && Config.HTTPHost != "localhost" {               // Open HTTP port iff HTTP server not listening on localhost
-		mapper.Map("TCP", Config.HTTPPort, "gecko-http")
+	port, err := mapper.Map("TCP", Config.StakingLocalPort, "gecko-staking") // Open staking port
+	if err == nil {
+		Config.StakingIP.Port = port
+	} else {
+		log.Warn("NAT traversal has failed. The node will be able to connect to less nodes.")
 	}
 
-	if Config.StakingIP.IsZero() {
-		log.Warn("NAT traversal has failed. The node will be able to connect to less nodes.")
+	if Config.HTTPHost != "127.0.0.1" && Config.HTTPHost != "localhost" { // Open HTTP port iff HTTP server not listening on localhost
+		_, _ = mapper.Map("TCP", Config.HTTPPort, "gecko-http")
 	}
 
 	node := node.Node{}
diff --git a/main/params.go b/main/params.go
index 03b8459..47ea5f8 100644
--- a/main/params.go
+++ b/main/params.go
@@ -284,16 +284,16 @@ func init() {
 		Config.DB = memdb.New()
 	}
 
-	Config.Nat = nat.GetRouter()
-
 	var ip net.IP
 	// If public IP is not specified, get it using shell command dig
 	if *consensusIP == "" {
+		Config.Nat = nat.GetRouter()
 		ip, err = Config.Nat.ExternalIP()
 		if err != nil {
 			ip = net.IPv4zero // Couldn't get my IP...set to 0.0.0.0
 		}
 	} else {
+		Config.Nat = nat.NewNoRouter()
 		ip = net.ParseIP(*consensusIP)
 	}
 
diff --git a/nat/nat.go b/nat/nat.go
index 8c351c7..bd79fee 100644
--- a/nat/nat.go
+++ b/nat/nat.go
@@ -4,6 +4,7 @@
 package nat
 
 import (
+	"errors"
 	"net"
 	"sync"
 	"time"
@@ -63,12 +64,16 @@ func NewPortMapper(log logging.Logger, r Router) Mapper {
 // Map sets up port mapping using given protocol, internal and external ports
 // and returns the final port mapped. It returns 0 if mapping failed after the
 // maximun number of retries
-func (dev *Mapper) Map(protocol string, intPort uint16, desc string) uint16 {
+func (dev *Mapper) Map(protocol string, intPort uint16, desc string) (uint16, error) {
 	mappedPort := make(chan uint16)
 
 	go dev.keepPortMapping(mappedPort, protocol, intPort, desc)
 
-	return <-mappedPort
+	port := <-mappedPort
+	if port == 0 {
+		return 0, errors.New("failed to map port")
+	}
+	return port, nil
 }
 
 // keepPortMapping runs in the background to keep a port mapped. It renews the