From 56268e4ae65ad20cdaaa435477aaa9202faff489 Mon Sep 17 00:00:00 2001
From: Shengjing Zhu <i@zhsj.me>
Date: Tue, 26 Jul 2022 18:48:04 +0800
Subject: [PATCH] fix: unmap ipv4-mapped ipv6 address

Closes: #4
---
 conf.go | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/conf.go b/conf.go
index 5c7f661..d8c64f0 100644
--- a/conf.go
+++ b/conf.go
@@ -112,6 +112,8 @@ func (p *peer) resolveHost() (netip.Addr, error) {
 		return netip.Addr{}, fmt.Errorf("resolve ip for %s: %w", p.host, err)
 	}
 	for _, ip := range ips {
+		// netstack doesn't seem to understand IPv4-mapped IPv6 addresses.
+		ip = ip.Unmap()
 		conn, err := net.DialUDP("udp", nil, net.UDPAddrFromAddrPort(netip.AddrPortFrom(ip, p.port)))
 		if err == nil {
 			conn.Close()