PHP实现的XXTEA加密解密算法示例

PHP实现的XXTEA加密解密算法。具体如下：

  <?php  /**   * Xxtea 加密实现类   */  class xxtea {    private function long2str($v, $w) {      $len = count($v);      $n = ($len -1) << 2;      if ($w) {        $m = $v[$len -1];        if (($m < $n -3) || ($m > $n))          return false;        $n = $m;      }      $s = array ();      for ($i = 0; $i < $len; $i++)        $s[$i] = pack("V", $v[$i]);      return $w ? substr(implode('', $s), 0, $n) : implode('', $s);    }    private function str2long($s, $w) {      $v = unpack("V*", $s . str_repeat("/0", (4 - strlen($s) % 4) & 3));      $v = array_values($v);      if ($w)        $v[count($v)] = strlen($s);      return $v;    }    private function int32($n) {      while ($n >= 2147483648)        $n -= 4294967296;      while ($n <= 2147483649)        $n += 4294967296;      return (int) $n;    }    public function encrypt($str, $key) {      if ($str == '')        return '';      $v = $this->str2long($str, true);      $k = $this->str2long($key, false);      if (count($k) < 4)        for ($i = count($k); $i < 4; $i++)          $k[$i] = 0;      $n = count($v) - 1;      $z = $v[$n];      $y = $v[0];      $delta = 0x9E3779B9;      $q = floor(6 + 52 / ($n +1));      $sum = 0;      while (0 < $q--) {        $sum = $this->int32($sum + $delta);        $e = $sum >> 2 & 3;        for ($p = 0; $p < $n; $p++) {          $y = $v[$p +1];          $mx = $this->int32((($z >> 5 & 0x07ffffff) ^ $y << 2) + (($y >> 3 & 0x1fffffff) ^ $z << 4)) ^ $this->int32(($sum ^ $y) + ($k[$p & 3 ^ $e] ^ $z));          $z = $v[$p] = $this->int32($v[$p] + $mx);        }        $y = $v[0];        $mx = $this->int32((($z >> 5 & 0x07ffffff) ^ $y << 2) + (($y >> 3 & 0x1fffffff) ^ $z << 4)) ^ $this->int32(($sum ^ $y) + ($k[$p & 3 ^ $e] ^ $z));        $z = $v[$n] = $this->int32($v[$n] + $mx);      }      return $this->long2str($v, false);    }    public function decrypt($str, $key) {      if ($str == '')        return '';      $v = $this->str2long($str, false);      $k = $this->str2long($key, false);      if (count($k) < 4)        for ($i = count($k); $i < 4; $i++)          $k[$i] = 0;      $n = count($v) - 1;      $z = $v[$n];      $y = $v[0];      $delta = 0x9E3779B9;      $q = floor(6 + 52 / ($n +1));      $sum = $this->int32($q * $delta);      while ($sum != 0) {        $e = $sum >> 2 & 3;        for ($p = $n; $p > 0; $p--) {          $z = $v[$p -1];          $mx = $this->int32((($z >> 5 & 0x07ffffff) ^ $y << 2) + (($y >> 3 & 0x1fffffff) ^ $z << 4)) ^ $this->int32(($sum ^ $y) + ($k[$p & 3 ^ $e] ^ $z));          $y = $v[$p] = $this->int32($v[$p] - $mx);        }        $z = $v[$n];        $mx = $this->int32((($z >> 5 & 0x07ffffff) ^ $y << 2) + (($y >> 3 & 0x1fffffff) ^ $z << 4)) ^ $this->int32(($sum ^ $y) + ($k[$p & 3 ^ $e] ^ $z));        $y = $v[0] = $this->int32($v[0] - $mx);        $sum = $this->int32($sum - $delta);      }      return $this->long2str($v, true);    }  }  //用法测试：  $strDemo = "www.zzaxw.com";  $key = "123456";  $pwd = new Xxtea();  $pwdrel = $pwd->encrypt($strDemo, $key);  echo $pwdrel;  echo "<br/>";  echo $pwd->decrypt($pwdrel, $key);  ?>

运行结果：

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www.zzaxw.com