Xray-core/transport/internet/udp/hub_openbsd.go

//go:build openbsd
// +build openbsd

package udp

import (
	"encoding/binary"

	"github.com/xtls/xray-core/common/net"
	"golang.org/x/sys/unix"
)

func retrieveOriginalDestFromControlMessages(msgs []unix.SocketControlMessage) net.Destination {
	var ip []byte
	var port uint16
	var haveAddress bool
	var havePort bool

	for _, msg := range msgs {
		if msg.Header.Level != unix.IPPROTO_IP {
			continue
		}

		switch msg.Header.Type {
		case unix.IP_RECVDSTADDR:
			if len(msg.Data) < 4 {
				continue
			}
			ip = append(ip[:0], msg.Data[:4]...)
			haveAddress = true
		case unix.IP_RECVDSTPORT:
			if len(msg.Data) < 2 {
				continue
			}
			port = binary.BigEndian.Uint16(msg.Data[:2])
			havePort = true
		}
	}

	if !haveAddress || !havePort || port == 0 {
		return net.Destination{}
	}

	return net.UDPDestination(net.IPAddress(ip), net.Port(port))
}

func RetrieveOriginalDest(oob []byte) net.Destination {
	msgs, err := unix.ParseSocketControlMessage(oob)
	if err != nil {
		return net.Destination{}
	}
	return retrieveOriginalDestFromControlMessages(msgs)
}

func ReadUDPMsg(conn *net.UDPConn, payload []byte, oob []byte) (int, int, int, *net.UDPAddr, error) {
	return conn.ReadMsgUDP(payload, oob)
}