可加密解密的base32

\Common\base32.php

<?php

namespace Common;

/**
 * 可加密解密的base32
 *
 * @author ForthXu
 */
class base32 {

    /**
     * 32个字符字典
     * @var array 
     */
    public $base64_config = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'm', 'n', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z', '2', '3', '4', '5', '6', '7', '8', '9']; //, 'l', 'o', '1', '0'//去掉容易混淆的字符

    /**
     * 打乱字符字典 和 加密密钥
     * @var string 
     */
    protected $key = "";

    public function __construct($key = "") {
        if (!empty($key)) {
            $rand = 0;
            foreach (str_split($key) as $s) {
                $rand *= ord($s);
            }
            srand($rand);
            shuffle($this->base64_config);

            $this->key = $key;
        }
    }

    /**
     * base32解密
     * @param string $str
     * @return string
     */
    public function decode($str) {
        $binaryString = "";
        foreach (str_split($str) as $s) {
            $char = array_search($s, $this->base64_config);
            $binaryString .= sprintf("%05b", $char);
        }
        $binaryArr = explode(" ", rtrim(chunk_split($binaryString, 8, " ")));


        //冗余去除
        $binaryArrLen = count($binaryArr);
        if (strlen($binaryArr[$binaryArrLen - 1]) != 8) {
            unset($binaryArr[$binaryArrLen - 1]);
        }

        $result = "";
        foreach ($binaryArr as $bin) {
            $result .= chr(base_convert($bin, 2, 10));
        }
        return $result;
    }

    /**
     * base32加密
     * @param string $str
     * @return string
     */
    public function encode($str) {
        $binaryString = "";
        foreach (str_split($str) as $s) {
            $binaryString .= sprintf('%08b', ord($s));
        }
        $binaryArr = explode(" ", rtrim(chunk_split($binaryString, 5, " ")));


        //冗余补全
        $binaryArrLen = count($binaryArr);
        if (strlen($binaryArr[$binaryArrLen - 1]) != 5) {
            $binaryArr[$binaryArrLen - 1] = str_pad($binaryArr[$binaryArrLen - 1], 5, '0', STR_PAD_RIGHT);
        }

        $result = "";
        foreach ($binaryArr as $bin) {
            $result .= $this->base64_config[base_convert($bin, 2, 10)];
        }
        return $result;
    }

    /**
     * 纯粹base32序列号带加密解密的方法是不做数据验证，这里增加混淆、有效时间、验证结果的处理
     * 可逆加密，结果使用base32保证无特殊字符
     * @param string $string 加密的内容
     * @param string $operation DECODE/ENCODE
     * @param int $expiry 参数在加密解密过程作用不同，加密结果的有效时间，解密对象是否需要验证时间
     * @param int $salt_len 加密盐长度，如果非0则每次加密后的结果都不一样，但解密结果是一样的
     * @param int $confirmation 用来校验的长度，最多32位，0不做校验，越长校验越完整
     * @return string 过期或者解密出错返回空字符串
     */
    public function authCode($string, $operation = 'DECODE', $expiry = 0, $salt_len = 0, $confirmation = 0) {
        $ckey_length = $salt_len;

        //输入的key
        //一半用来生成密钥用于混淆
        $keya = md5(substr($this->key, 0, 16));
        //一半用来生成hash用于验证
        $keyb = md5(substr($this->key, 16, 16));
        //获取或者生成salt用于混淆
        $keyc = $ckey_length ? ($operation == 'DECODE' ? substr($string, 0, $ckey_length) : substr(md5(microtime()), -$ckey_length)) : '';

        //生产加了salt的混淆密钥
        $cryptkey = $keya . md5($keya . $keyc);
        $key_length = strlen($cryptkey);

        //加密的内容：salt+使用salt和keya产生的密钥做移位替换（十位的时间戳 + $confirmation位验证keyb验证hash + 字符串）
        $string = $operation == 'DECODE' ? $this->decode(substr($string, $ckey_length)) : ($expiry > 0 ? sprintf('%010d', $expiry + time()) : "") . ($confirmation > 0 ? substr(md5($string . $keyb), 0, $confirmation) : "") . $string;
        $string_length = strlen($string);

        //移位替换
        $result = '';
        //产生一个异或掩码库
        $box = range(0, 255);
        //根据密钥产生用一个混淆库
        $rndkey = array();
        for ($i = 0; $i <= 255; $i++) {
            $rndkey[$i] = ord($cryptkey[$i % $key_length]);
        }
        //混淆掩码库，i跟往前j个做交换处理
        for ($j = $i = 0; $i < 256; $i++) {
            $j = ($j + $box[$i] + $rndkey[$i]) % 256;

            $tmp = $box[$i];
            $box[$i] = $box[$j];
            $box[$j] = $tmp;
        }
        //使用掩码做异或操作
        for ($a = $j = $i = 0; $i < $string_length; $i++) {
            $a = ($a + 1) % 256; //往前一位
            $j = ($j + $box[$a]) % 256;
            //再做一次交换
            $tmp = $box[$a];
            $box[$a] = $box[$j];
            $box[$j] = $tmp;
            $result .= chr(ord($string[$i]) ^ ($box[($box[$a] + $box[$j]) % 256]));
        }

        if ($operation == 'DECODE') {
            if (
                    ($expiry == 0 || ($expiry > 0 && substr($result, 0, 10) - time() >= 0)) &&
                    ($confirmation < 1 || ($expiry == 0 ? substr($result, 0, $confirmation) == substr(md5(substr($result, $confirmation) . $keyb), 0, $confirmation) : substr($result, 10, $confirmation) == substr(md5(substr($result, 10 + $confirmation) . $keyb), 0, $confirmation)))
            ) {
                return $expiry == 0 ? ($confirmation > 0 ? substr($result, $confirmation) : substr($result, 0)) : ($confirmation > 0 ? substr($result, 10 + $confirmation) : substr($result, 10));
            } else {
                return '';
            }
        } else {
            return $keyc . str_replace('=', '', $this->encode($result));
        }
    }

}

/*
    $baseBs = new \Common\base32("1234");
    for($i=4294967290;$i<4294967300;$i++){
        $encode = $baseBs->encode($i);
        var_dump($encode);
        $decode = $baseBs->decode($encode);
        var_dump($decode);

        $encode = $baseBs->authCode($i, "ENCODE",0,0,10);
        var_dump($encode);
        $decode = $baseBs->authCode($encode, "DECODE",0,0,10);
        var_dump($decode);
        echo "\n";
    }
 */