经典PHP加密解密函数Authcode()修复版代码

 Authcode这个函数很多人都使用,这函数来自Discuz程序,用于加密解密字符串,可以设置钥匙(key)和过期时间,在很多时候都用得着。原版的函数代码可能会生成+、/、&这样的字符,导致通过URL传值取回时被转义,导致无法解密。火端网络稍加修改,把这几个字符替换成其它字符,解密时再替换回去,这样就完美了!

function authcode($string, $operation = 'DECODE', $key = '', $expiry = 0){
 
 if($operation == 'DECODE') {
  $string = str_replace('[a]','+',$string);
  $string = str_replace('[b]','&',$string);
  $string = str_replace('','/',$string);
 }
    $ckey_length = 4;
    $key = md5($key ? $key : 'livcmsencryption ');
    $keya = md5(substr($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)) {
   
            return substr($result, 26);
        } else {
            return '';
        }
    } else {
  $ustr = $keyc.str_replace('=', '', base64_encode($result));
  $ustr = str_replace('+','[a]',$ustr);
  $ustr = str_replace('&','[b]',$ustr);
  $ustr = str_replace('/','',$ustr);
        return $ustr;
    }
}

php生成随机唯一邀请码/优惠码 固定长度

more

function make_coupon_card() {    
    $code = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ';    
    $rand = $code[rand(0,25)]    
        .strtoupper(dechex(date('m')))    
        .date('d').substr(time(),-5)    
        .substr(microtime(),2,5)    
        .sprintf('%02d',rand(0,99));    
    for(    
        $a = md5( $rand, true ),    
        $s = '0123456789ABCDEFGHIJKLMNOPQRSTUV',    
        $d = '',    
        $f = 0;    
        $f < 8;  
        $g = ord( $a[ $f ] ),    
        $d .= $s[ ( $g ^ ord( $a[ $f + 8 ] ) ) - $g & 0x1F ],    
        $f++    
    );    
    return $d;    
}