php 用户验证 base64验证方法

时间：2015-01-23 来源：西部数据作者：西部数据

function dsetcookie($var, $value, $life = 0, $prefix = 1) {

global $cookiedomain, $cookiepath, $addtime, $_server;

setcookie($var, $value,$life ? $addtime + $life : 0, $cookiepath,$cookiedomain, $_server['server_port'] == 443 ? 1 : 0);

}

function authcode($string, $operation = 'decode', $key = '', $expiry = 0) {

    global $webaddr;

    $auth_key=md5($webaddr);

$ckey_length = 4;

$key = md5($key ? $key : $auth_key);

$keya = md5(substr($key, 0, 16));

$keyb = md5(substr($key, 16, 16));

$keyc = $ckey_length ? ($operation == 'decode' ? substr($string, 0, $ckey_length): substr(md5(microtime()), -$ckey_length)) : '';

$cryptkey = $keya.md5($keya.$keyc);

$key_length = strlen($cryptkey);

$string = $operation == 'decode' ? base64_decode(substr($string, $ckey_length)) : sprintf('%010d', $expiry ? $expiry + time() : 0).substr(md5($string.$keyb), 0, 16).$string;

$string_length = strlen($string);

$result = '';

$box = range(0, 255);

$rndkey = array();

for($i = 0; $i <= 255; $i++) {

  $rndkey[$i] = ord($cryptkey[$i % $key_length]);

}

for($j = $i = 0; $i < 256; $i++) {

  $j = ($j + $box[$i] + $rndkey[$i]) % 256;

  $tmp = $box[$i];

  $box[$i] = $box[$j];

  $box[$j] = $tmp;

}

for($a = $j = $i = 0; $i < $string_length; $i++) {

  $a = ($a + 1) % 256;

  $j = ($j + $box[$a]) % 256;

  $tmp = $box[$a];

  $box[$a] = $box[$j];

  $box[$j] = $tmp;

  $result .= chr(ord($string[$i]) ^ ($box[($box[$a] + $box[$j]) % 256]));

}

if($operation == 'decode') {

  if((substr($result, 0, 10) == 0 || substr($result, 0, 10) - time() > 0) && substr($result, 10, 16) == substr(md5(substr($result, 26).$keyb), 0, 16)) {//开源代码phpfensi.com

   return substr($result, 26);

  } else {

   return '';

  }

} else {

  return $keyc.str_replace('=', '', base64_encode($result));

}

}