source: Common/NetworkAddress.php

<?php

define('IPV4_BIT_WIDTH', 32);

class NetworkAddressIPv4
{
  public int $Address;
  public int $Prefix;

  function __construct()
  {
    $this->Address = 0;
    $this->Prefix = 0;
  }

  function GetNetMask(): int
  {
    return ((1 << IPV4_BIT_WIDTH) - 1) ^ ((1 << (IPV4_BIT_WIDTH - $this->Prefix)) - 1);
  }

  function AddressToString(): string
  {
    return implode('.', array(($this->Address >> 24) & 255, ($this->Address >> 16) & 255, ($this->Address >> 8) & 255, ($this->Address & 255)));
  }

  function AddressFromString(string $Value): void
  {
    $Parts = explode('.', $Value);
    $this->Address = ($Parts[0] << 24) | ($Parts[1] << 16) | ($Parts[2] << 8) | $Parts[3];
  }

  function GetRange(): array
  {
    $From = new NetworkAddressIPv4();
    $From->Address = $this->Address;
    $From->Prefix = IPV4_BIT_WIDTH;
    $HostMask = 0xffffffff ^ $this->GetNetMask();
    $To = new NetworkAddressIPv4();
    $To->Address = $From->Address + $HostMask;
    $To->Prefix = IPV4_BIT_WIDTH;
    return array('From' => $From, 'To' => $To);
  }

  function ChangePrefix(int $NewPrefix): void
  {
    $this->Prefix = $NewPrefix;
    if ($this->Prefix > IPV4_BIT_WIDTH) $this->Prefix = IPV4_BIT_WIDTH;
    if ($this->Prefix < 0) $this->Prefix = 0;
    $this->Address = $this->Address & $this->GetNetMask();
  }

  function Contain(NetworkAddressIPv4 $Address): bool
  {
    $UpperNetmask = $this->GetNetMask();
    if (($this->Prefix < $Address->Prefix) and (($Address->Address & $UpperNetmask) == ($this->Address & $UpperNetmask))) $Result = true;
      else $Result = false;
    return $Result;
  }
}

define('IPV6_BIT_WIDTH', 128);

class NetworkAddressIPv6
{
  public string $Address;
  public int $Prefix;

  function __construct()
  {
    $this->Address = 0;
    $this->Prefix = 0;
  }

  function GetNetMask(): string
  {
    return Int128Xor(Int128Sub(Int128Shl(IntToInt128(1), IntToInt128(IPV6_BIT_WIDTH)), IntToInt128(1)),
      Int128Sub(Int128Shl(IntToInt128(1), IntToInt128(IPV6_BIT_WIDTH - $this->Prefix)), IntToInt128(1)));
  }

  function AddressToString(): string
  {
    return inet_ntop($this->Address);
  }

  function AddressFromString(string $Value)
  {
    $this->Address = inet_pton($Value);
  }

  function ChangePrefix(int $NewPrefix): void
  {
    $this->Prefix = $NewPrefix;
    if ($this->Prefix > IPV6_BIT_WIDTH) $this->Prefix = IPV6_BIT_WIDTH;
    if ($this->Prefix < 0) $this->Prefix = 0;
    $this->Address = Int128And($this->Address, $this->GetNetMask());
  }

  function GetOctets(): array
  {
    $Result = array();
    $Data = array_reverse(unpack('C*', $this->Address));
    foreach ($Data as $Item)
    {
      $Result[] = dechex($Item & 15);
      $Result[] = dechex(($Item >> 4) & 15);
    }
    return $Result;
  }

  function EncodeMAC(string $MAC): void
  {
    $MAC = explode(':', $MAC);
    $Data = unpack('C*', $this->Address);
    $Data[9] = hexdec($MAC[0]) ^ 0x02;
    $Data[10] = hexdec($MAC[1]);
    $Data[11] = hexdec($MAC[2]);
    $Data[12] = 0xff;
    $Data[13] = 0xfe;
    $Data[14] = hexdec($MAC[3]);
    $Data[15] = hexdec($MAC[4]);
    $Data[16] = hexdec($MAC[5]);
    $this->Address = pack_array('C*', $Data);
  }

  function Contain(NetworkAddressIPv6 $Address): bool
  {
    $UpperNetmask = $this->GetNetMask();
    if (($this->Prefix < $Address->Prefix) and ((Int128Equal(Int128And($Address->Address, $UpperNetmask), Int128And($this->Address, $UpperNetmask))))) $Result = true;
      else $Result = false;
    return $Result;
  }
}