wt_in6_addr.go

/* SPDX-License-Identifier: MIT
 *
 * Copyright (C) 2019 WireGuard LLC. All Rights Reserved.
 */

package winipcfg

import (
	"fmt"
	"net"
)

// https://docs.microsoft.com/en-us/windows/desktop/api/in6addr/ns-in6addr-in6_addr
// IN6_ADDR defined in in6addr.h
type wtIn6Addr struct {
	Byte [16]uint8 // Windows type [16]UCHAR
}

func (addr *wtIn6Addr) toNetIp() net.IP {

	if addr == nil {
		return nil
	}

	return net.IP{
		byte(addr.Byte[0]),
		byte(addr.Byte[1]),
		byte(addr.Byte[2]),
		byte(addr.Byte[3]),
		byte(addr.Byte[4]),
		byte(addr.Byte[5]),
		byte(addr.Byte[6]),
		byte(addr.Byte[7]),
		byte(addr.Byte[8]),
		byte(addr.Byte[9]),
		byte(addr.Byte[10]),
		byte(addr.Byte[11]),
		byte(addr.Byte[12]),
		byte(addr.Byte[13]),
		byte(addr.Byte[14]),
		byte(addr.Byte[15]),
	}
}

// Compares two wtIn6Addr structs for equality. Note that the function will return false if either of structs is nil,
// even if the other is also nil.
func (addr *wtIn6Addr) equal(other *wtIn6Addr) bool {

	if addr == nil || other == nil {
		return false
	}

	for i := 0; i < 16; i++ {
		if addr.Byte[i] != other.Byte[i] {
			return false
		}
	}

	return true
}

func (addr *wtIn6Addr) matches(ip *net.IP) bool {

	if addr == nil {
		return false
	}

	if len(*ip) != net.IPv6len || ip.To4() != nil {
		return false
	}

	for i := 0; i < 16; i++ {
		if addr.Byte[i] != (*ip)[i] {
			return false
		}
	}

	return true
}

func netIpToWtIn6Addr(ip net.IP) (*wtIn6Addr, error) {

	if len(ip) != net.IPv6len || ip.To4() != nil {
		return nil, fmt.Errorf("netIpToWtIn6Addr() requires IPv6 addresses")
	}

	in6_addr := wtIn6Addr{}

	for i := 0; i < 16; i++ {
		in6_addr.Byte[i] = ip[i]
	}

	return &in6_addr, nil
}