从MySQL数据库检索时出现AES_DECRYPT问题


Issue with AES_DECRYPT when retrieving from MySQL database

好的,我有这个页面,应该允许用户使用他们的密码登录,密码在数据库中用AES加密。我想从数据库中取出加密的密码,对其进行解密,并将其与用户输入的密码进行比较。这是我的代码:

<?php
session_start();
$validUser = false;
// see if they want to logout from a current session
$tOption = $_GET['cmd'];
if($tOption=="logout") {
    unset($_SESSION['SAFEUSER']);
}
?>
<html>
<body>
<?php
// are they attempting to log into the menu?
// alternative syntax that uses the submit button's value
// if(   $_POST['Fsubmit'] == "lookupnow" ) {

if(   ($_POST['Femail'] > "") or ($_POST['Fpassword'] > "")  ) {
    // look 'em up in the database to validate credentials
    // establish values for DB credentials
    $hostname = 'localhost';
    $dbname = ''; 
    $username = '';
    $userpass = '';
    $passkey = "sgjbasjgbaslhflshfoashf";
    // get connected to the DB
    try {
      $DBH = new PDO("mysql:host=$hostname;dbname=$dbname", $username, $userpass);
    }
    catch(PDOException $e) {
        echo $e->getMessage();
    }
    $tEmail = $_POST['Femail'];
    $tPassword = $_POST['Fpassword'];
    /*$secureSQL = 'SELECT FirstName, LastName, Phone from Members WHERE Email="' 
            . $tEmail . '" AND Password="' . $tPassword . '"';*/
    $secureSQL = 'SELECT FirstName, LastName, Phone from Members WHERE Email="' 
            . $tEmail . '" AND AES_DECRYPT(Password, $passkey) ="' . $tPassword . '"';
    //echo $secureSQL . "<br>";
    // estalish SQL query  
    $STH = $DBH->query($secureSQL);
    # setting the fetch mode -- this comes into effect when the fetch() function is called
    $STH->setFetchMode(PDO::FETCH_ASSOC);
    while($row = $STH->fetch()) {
        $validUser = true;
        $_SESSION['SAFEUSER'] = true;
    }
    if($validUser==false) {
        echo "<font color='red'>Those credentials were not authenticated.</font><br/><br/>";
    }

}
// are they logged in?
if(!$_SESSION['SAFEUSER']) {
    // if not, make them login
?>
    Please enter your credentials:<br />
    <form method="post" action="mysecuremenu.php">
        Your email address: <input type="text" name="Femail"><br>
        Your password: <input type="password" name="Fpassword"></br>
        <input type="submit" name="Fsubmit" value="lookupnow">
    </form>
<?php   
} else {
    // otherwise, show them the menu
?>
<h2>Please select one of the following:</h2>
<ul>
    <li><a href="MySecureFirstDBForm.php">Enter a new employee</a></li>
    <li><a href="mySecuredbviewall_withdatatable.php">View all employees</a></li>
    <li><a href="mysecuremenu.php?cmd=logout">Logout</a></li>
</ul>
<?php
} // end if(safeuser)
?>
</body>
</html>

我得到这个错误:

Fatal error: Call to a member function setFetchMode() on a non-object on line 58

我觉得这与我的SELECT语句有关,因为我在上面评论的那个语句适用于使用非加密密码登录。我将感谢所有的帮助。谢谢

您的查询中有语法错误,稍后会详细介绍。如果您检查了对PDO的呼叫是否有错误,您就会找到它。PDO不会显式标记错误,除非您要求它这样做,所以您需要检查对$DBH->query(...) 的调用的返回值

$STH = $DBH->query($secureSQL);
if ($STH === false) {
    $errorInfo = $DBH->errorInfo();
    echo $errorInfo[0].':'.$errorInfo[1].' ('.$errorInfo[2].')';
    exit;
}

(您可以将PDO设置为在遇到错误时抛出异常,并使用try...catch块来处理它。这是读者的练习)

现在-语法错误。你正在构建这样的查询:

 $secureSQL = 
    'SELECT FirstName, LastName, Phone from Members WHERE Email="' 
            . $tEmail . '" AND AES_DECRYPT(Password, $passkey) ="' . $tPassword . '"';

您已经尝试对$passkey变量进行插值,但字符串的这一部分用单引号括起来,因此插值不起作用。您已经连接了其余的参数,所以不清楚为什么您在这里做了一些不同的事情。

您还省略了在$passkey周围加单引号,因此即使插值有效,查询也会失败。简单地交换你对单引号和双引号的使用会让这变得更容易。

你需要这个:

 $secureSQL = 
    "SELECT FirstName, LastName, Phone from Members WHERE Email='" 
            . $tEmail . "' AND AES_DECRYPT(Password, '$passkey') ='" . $tPassword . "'";

还有更多。

您已将用户输入直接添加到查询字符串中,而无需任何形式的转义。这让您对SQL注入持开放态度。再加上加密密码,你就可以公开邀请黑客攻击你的数据库。至少应该使用PDO::quote()来转义变量,但更好的方法是使用准备好的语句并完全避免注入风险。(读者的另一个练习)。

最后(这已经在评论中介绍过了)不要加密密码-对它们进行哈希PHP在PHP 5.5+中为此提供了password_hash(),并且有一个可以用于早期版本的填充程序。

如果你的教授教你使用AES_ENCRYPT()来保护密码,你真的应该让他负责