From d15e423562b451a9e059cb1c39608f26a938cf3a Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Serhat=20=C5=9Eevki=20Din=C3=A7er?= <jfcgauss@gmail.com>
Date: Tue, 23 Nov 2021 17:14:08 +0300
Subject: [PATCH] p2p/enode: store local port number as uint16 (#23926)

---
 p2p/enode/localnode.go            | 17 ++++++++++-------
 p2p/simulations/adapters/types.go |  2 +-
 2 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/p2p/enode/localnode.go b/p2p/enode/localnode.go
index 4827b6c0a..a18204e75 100644
--- a/p2p/enode/localnode.go
+++ b/p2p/enode/localnode.go
@@ -63,7 +63,7 @@ type LocalNode struct {
 type lnEndpoint struct {
 	track                *netutil.IPTracker
 	staticIP, fallbackIP net.IP
-	fallbackUDP          int
+	fallbackUDP          uint16 // port
 }
 
 // NewLocalNode creates a local node.
@@ -208,8 +208,8 @@ func (ln *LocalNode) SetFallbackUDP(port int) {
 	ln.mu.Lock()
 	defer ln.mu.Unlock()
 
-	ln.endpoint4.fallbackUDP = port
-	ln.endpoint6.fallbackUDP = port
+	ln.endpoint4.fallbackUDP = uint16(port)
+	ln.endpoint6.fallbackUDP = uint16(port)
 	ln.updateEndpoints()
 }
 
@@ -261,7 +261,7 @@ func (ln *LocalNode) updateEndpoints() {
 }
 
 // get returns the endpoint with highest precedence.
-func (e *lnEndpoint) get() (newIP net.IP, newPort int) {
+func (e *lnEndpoint) get() (newIP net.IP, newPort uint16) {
 	newPort = e.fallbackUDP
 	if e.fallbackIP != nil {
 		newIP = e.fallbackIP
@@ -277,15 +277,18 @@ func (e *lnEndpoint) get() (newIP net.IP, newPort int) {
 
 // predictAddr wraps IPTracker.PredictEndpoint, converting from its string-based
 // endpoint representation to IP and port types.
-func predictAddr(t *netutil.IPTracker) (net.IP, int) {
+func predictAddr(t *netutil.IPTracker) (net.IP, uint16) {
 	ep := t.PredictEndpoint()
 	if ep == "" {
 		return nil, 0
 	}
 	ipString, portString, _ := net.SplitHostPort(ep)
 	ip := net.ParseIP(ipString)
-	port, _ := strconv.Atoi(portString)
-	return ip, port
+	port, err := strconv.ParseUint(portString, 10, 16)
+	if err != nil {
+		return nil, 0
+	}
+	return ip, uint16(port)
 }
 
 func (ln *LocalNode) invalidate() {
diff --git a/p2p/simulations/adapters/types.go b/p2p/simulations/adapters/types.go
index 1da464a10..aeb8ef777 100644
--- a/p2p/simulations/adapters/types.go
+++ b/p2p/simulations/adapters/types.go
@@ -242,7 +242,7 @@ func assignTCPPort() (uint16, error) {
 	if err != nil {
 		return 0, err
 	}
-	p, err := strconv.ParseInt(port, 10, 32)
+	p, err := strconv.ParseUint(port, 10, 16)
 	if err != nil {
 		return 0, err
 	}