<?php


function _imagecache_hmac_base64($data, $key) {
  // Keys longer than 64 bytes are first hashed.
  if (strlen($key) > 64) {
    $key = pack('H*', sha1($key));
  }

  $key = str_pad($key, 64, chr(0x00));
  $ipad = str_repeat(chr(0x36), 64);
  $opad = str_repeat(chr(0x5c), 64);

  $ipad = $ipad ^ $key;
  $opad = $opad ^ $key;

  $hmac = base64_encode(pack('H*', sha1($opad . pack('H*', sha1($ipad . $data)))));
  // Modify the hmac so it's safe to use in URLs.
  return strtr($hmac, array('+' => '-', '/' => '_', '=' => ''));
}

function sha1_hmac_base64($data, $key) {
  $hmac = base64_encode(hash_hmac('sha1', $data, $key, TRUE));
  // Modify the hmac so it's safe to use in URLs.
  return strtr($hmac, array('+' => '-', '/' => '_', '=' => ''));
}

$keys[] = "Jefe";
$datas[] = "what do ya want for nothing?";

$keys[] = str_repeat(chr(0xaa), 80);
$datas[] = "Test Using Larger Than Block-Size Key - Hash Key First";

$keys[] = str_repeat(chr(0xaa), 80);
$datas[] = "Test Using Larger Than Block-Size Key and Larger Than One Block-Size Data";

$keys[] = "Test Using Larger Than Block-Size Key and Larger Than One Block-Size Data";
$datas[] = "Test Using Larger Than Block-Size Key and Larger Than One Block-Size Data";

$keys[] = str_repeat(chr(0x5c), 90);
$datas[] = str_repeat(chr(0x5c), 900);

foreach ($datas as $i => $data) {
  if (_imagecache_hmac_base64($data, $keys[$i]) !== sha1_hmac_base64($data, $keys[$i])) {
    throw new Exception($data);
  }
}

echo "success!\n";