fix: correctly handle ipv6 zone

Author: wwqgtxx

common/net/packet/packet_posix.go

@@ -45,7 +45,11 @@ func (c *enhanceUDPConn) WaitReadFrom() (data []byte, put func(), addr net.Addr,
 				addr = &net.UDPAddr{IP: ip[:], Port: from.Port}
 			case *syscall.SockaddrInet6:
 				ip := from.Addr // copy from.Addr; ip escapes, so this line allocates 16 bytes
-				addr = &net.UDPAddr{IP: ip[:], Port: from.Port, Zone: strconv.FormatInt(int64(from.ZoneId), 10)}
+				zone := ""
+				if from.ZoneId != 0 {
+					zone = strconv.FormatInt(int64(from.ZoneId), 10)
+				}
+				addr = &net.UDPAddr{IP: ip[:], Port: from.Port, Zone: zone}
 			}
 		}
 		// udp should not convert readN == 0 to io.EOF

common/net/packet/packet_windows.go

@@ -54,7 +54,11 @@ func (c *enhanceUDPConn) WaitReadFrom() (data []byte, put func(), addr net.Addr,
 				addr = &net.UDPAddr{IP: ip[:], Port: from.Port}
 			case *windows.SockaddrInet6:
 				ip := from.Addr // copy from.Addr; ip escapes, so this line allocates 16 bytes
-				addr = &net.UDPAddr{IP: ip[:], Port: from.Port, Zone: strconv.FormatInt(int64(from.ZoneId), 10)}
+				zone := ""
+				if from.ZoneId != 0 {
+					zone = strconv.FormatInt(int64(from.ZoneId), 10)
+				}
+				addr = &net.UDPAddr{IP: ip[:], Port: from.Port, Zone: zone}
 			}
 		}
 		// udp should not convert readN == 0 to io.EOF

dns/system_windows.go

@@ -3,8 +3,9 @@
 package dns
 
 import (
-	"net"
+	"net/netip"
 	"os"
+	"strconv"
 	"syscall"
 	"unsafe"
 
@@ -23,28 +24,31 @@ func dnsReadConfig() (servers []string, err error) {
 			if err != nil {
 				continue
 			}
-			var ip net.IP
+			var ip netip.Addr
 			switch sa := sa.(type) {
 			case *syscall.SockaddrInet4:
-				ip = net.IPv4(sa.Addr[0], sa.Addr[1], sa.Addr[2], sa.Addr[3])
+				ip = netip.AddrFrom4(sa.Addr)
 			case *syscall.SockaddrInet6:
-				ip = make(net.IP, net.IPv6len)
-				copy(ip, sa.Addr[:])
-				if ip[0] == 0xfe && ip[1] == 0xc0 {
+				if sa.Addr[0] == 0xfe && sa.Addr[1] == 0xc0 {
 					// Ignore these fec0/10 ones. Windows seems to
 					// populate them as defaults on its misc rando
 					// interfaces.
 					continue
 				}
+				ip = netip.AddrFrom16(sa.Addr)
+				if sa.ZoneId != 0 {
+					ip = ip.WithZone(strconv.FormatInt(int64(sa.ZoneId), 10))
+				}
 				//continue
 			default:
 				// Unexpected type.
 				continue
 			}
-			if slices.Contains(servers, ip.String()) {
+			ipStr := ip.String()
+			if slices.Contains(servers, ipStr) {
 				continue
 			}
-			servers = append(servers, ip.String())
+			servers = append(servers, ipStr)
 		}
 	}
 	return