From 193cf8d6a5d6b8844d7f9b33b2d0ecb46098255e Mon Sep 17 00:00:00 2001
From: "Jason A. Donenfeld" <Jason@zx2c4.com>
Date: Thu, 17 Mar 2022 22:23:02 -0600
Subject: [PATCH] conn: use netip for std bind

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
---
 conn/bind_std.go | 39 +++++++++++++--------------------------
 1 file changed, 13 insertions(+), 26 deletions(-)

diff --git a/conn/bind_std.go b/conn/bind_std.go
index ab800ba..e0f6cdd 100644
--- a/conn/bind_std.go
+++ b/conn/bind_std.go
@@ -27,7 +27,7 @@ type StdNetBind struct {
 
 func NewStdNetBind() Bind { return &StdNetBind{} }
 
-type StdNetEndpoint net.UDPAddr
+type StdNetEndpoint netip.AddrPort
 
 var (
 	_ Bind     = (*StdNetBind)(nil)
@@ -36,18 +36,13 @@ var (
 
 func (*StdNetBind) ParseEndpoint(s string) (Endpoint, error) {
 	e, err := netip.ParseAddrPort(s)
-	return (*StdNetEndpoint)(&net.UDPAddr{
-		IP:   e.Addr().AsSlice(),
-		Port: int(e.Port()),
-		Zone: e.Addr().Zone(),
-	}), err
+	return (*StdNetEndpoint)(&e), err
 }
 
 func (*StdNetEndpoint) ClearSrc() {}
 
 func (e *StdNetEndpoint) DstIP() netip.Addr {
-	a, _ := netip.AddrFromSlice((*net.UDPAddr)(e).IP)
-	return a
+	return (*netip.AddrPort)(e).Addr()
 }
 
 func (e *StdNetEndpoint) SrcIP() netip.Addr {
@@ -55,18 +50,12 @@ func (e *StdNetEndpoint) SrcIP() netip.Addr {
 }
 
 func (e *StdNetEndpoint) DstToBytes() []byte {
-	addr := (*net.UDPAddr)(e)
-	out := addr.IP.To4()
-	if out == nil {
-		out = addr.IP
-	}
-	out = append(out, byte(addr.Port&0xff))
-	out = append(out, byte((addr.Port>>8)&0xff))
-	return out
+	b, _ := (*netip.AddrPort)(e).MarshalBinary()
+	return b
 }
 
 func (e *StdNetEndpoint) DstToString() string {
-	return (*net.UDPAddr)(e).String()
+	return (*netip.AddrPort)(e).String()
 }
 
 func (e *StdNetEndpoint) SrcToString() string {
@@ -162,18 +151,15 @@ func (bind *StdNetBind) Close() error {
 
 func (*StdNetBind) makeReceiveIPv4(conn *net.UDPConn) ReceiveFunc {
 	return func(buff []byte) (int, Endpoint, error) {
-		n, endpoint, err := conn.ReadFromUDP(buff)
-		if endpoint != nil {
-			endpoint.IP = endpoint.IP.To4()
-		}
-		return n, (*StdNetEndpoint)(endpoint), err
+		n, endpoint, err := conn.ReadFromUDPAddrPort(buff)
+		return n, (*StdNetEndpoint)(&endpoint), err
 	}
 }
 
 func (*StdNetBind) makeReceiveIPv6(conn *net.UDPConn) ReceiveFunc {
 	return func(buff []byte) (int, Endpoint, error) {
-		n, endpoint, err := conn.ReadFromUDP(buff)
-		return n, (*StdNetEndpoint)(endpoint), err
+		n, endpoint, err := conn.ReadFromUDPAddrPort(buff)
+		return n, (*StdNetEndpoint)(&endpoint), err
 	}
 }
 
@@ -183,11 +169,12 @@ func (bind *StdNetBind) Send(buff []byte, endpoint Endpoint) error {
 	if !ok {
 		return ErrWrongEndpointType
 	}
+	addrPort := (*netip.AddrPort)(nend)
 
 	bind.mu.Lock()
 	blackhole := bind.blackhole4
 	conn := bind.ipv4
-	if nend.IP.To4() == nil {
+	if addrPort.Addr().Is6() {
 		blackhole = bind.blackhole6
 		conn = bind.ipv6
 	}
@@ -199,6 +186,6 @@ func (bind *StdNetBind) Send(buff []byte, endpoint Endpoint) error {
 	if conn == nil {
 		return syscall.EAFNOSUPPORT
 	}
-	_, err = conn.WriteToUDP(buff, (*net.UDPAddr)(nend))
+	_, err = conn.WriteToUDPAddrPort(buff, *addrPort)
 	return err
 }