PHP 简单的加密解密方法

/** * @desc加密 * @param string $str 待加密字符串 * @param string $key 密钥 * @return string */function encrypt($str, $key){ ???$mixStr = md5(date(‘Y-m-d H:i:s‘).rand(1000)); ???$tmp = ‘‘; ???$strLen = strlen($str); ???for($i=0, $j=0; $i<$strLen; $i++, $j++){ ???????$j = $j == 32 ? 0 : $j; ???????$tmp .= $mixStr[$j].($str[$i] ^ $mixStr[$j]); ???} ???return base64_encode(bind_key($tmp, $key));}/** * @desc解密 * @param string $str 待解密字符串 * @param string $key 密钥 * @return string */function decrypt($str, $key){ ???$str = bind_key(base64_decode($str), $key); ???$strLen = strlen($str); ???$tmp = ‘‘; ???for($i=0; $i<$strLen; $i++){ ???????$tmp .= $str[$i] ^ $str[++$i]; ???} ???return $tmp;}/** * @desc辅助方法 用密钥对随机化操作后的字符串进行处理 * @param $str * @param $key * @return string */function bind_key($str, $key){ ???$encrypt_key = md5($key); ???$tmp = ‘‘; ???$strLen = strlen($str); ???for($i=0, $j=0; $i<$strLen; $i++, $j++){ ???????$j = $j == 32 ? 0 : $j; ???????$tmp .= $str[$i] ^ $encrypt_key[$j]; ???} ???return $tmp;}