encrypt_decrypt()函数只在我尝试解密

时间:2016-01-30 19:09:51

标签: php mysql encryption login

我一直致力于学校的侧面项目,用户可以登录并记录他们拥有的志愿者小时数。我已完成注册页面,它连接到数据库并存储用户信息,包括加密密码。 我遇到的问题是用户尝试登录时。输入密码后,程序进入数据库并检索散列函数,但是当我尝试解密时,解密的行是空白的。我不确定为什么会发生这种情况,但是我想一些帮助解决这个问题。谢谢。

以下是我的登录页面和encrypt_decrypt()函数的代码:

login.php页面:

<?php

include("encrypt_decrypt.php");

$username="root";
$password="";
$server="localhost";
$db_name="userauthentication";

$uname="";
$pword="";
$error_msg = "";

if(isset($_POST["submit"])){

    $db_handle = mysqli_connect($server, $username, $password);
    $db_found = mysqli_select_db($db_handle, $db_name);

    $uname = $_POST["uname"];
    $uname = htmlspecialchars($uname);
    $uname = mysqli_real_escape_string($db_handle, $uname);

    $pword = $_POST["pword"];
    $pword = htmlspecialchars($pword);
    $pword = mysqli_real_escape_string($db_handle, $pword);

        if($db_found){
            if($uname == "admin"){
                $SQL = "SELECT * FROM  WHERE username = '$uname' AND pword = '$pword'";
                $result = mysqli_query($db_handle, $SQL);

                $num_rows = mysqli_num_rows($result);

                    if(isset($num_rows) && $num_rows > 0){
                        session_start();
                        $_SESSION['login'] = "2";
                        header("Location: adminpage.html");
                    }else{
                        print("error");
                    }
            }else{
                $SQL = "SELECT * FROM login WHERE username = '$uname'";
                $result = mysqli_query($db_handle, $SQL);

                $num_rows = mysqli_num_rows($result);

                if($num_rows > 0){

                    $db_field = mysqli_fetch_assoc($result);

                    $pword_match = $db_field['password'];
                    $pword_match = encrypt_decrypt('decrypt', $pword_match);

                    print ($pword . "<br>");
                    print $pword_match;

                    if($pword == $pword_match){
                        session_start();
                        $_SESSION['login'] = "1";
                        header("Location: mainpage.html");
                    }else{
                        $error_msg = "<span class='error_msg'>Wrong password!</span>";
                        print $error_msg;
                    }
                }else if($num_rows == 0){
                    $error_msg = "<span class='error_msg'>Wrong username!</span>";
                    print $error_msg;
                }
            }
        }else{
            $error_msg = "<span class='register'>Could not connect to database!</span>";
            print $error_msg;
        }
    }
?>

这些是在login.php文件中给我带来麻烦的行:

$db_field = mysqli_fetch_assoc($result);

$pword_match = $db_field['password'];
$pword_match = encrypt_decrypt('decrypt', $pword_match);

print ($pword . "<br>");
print $pword_match;

我刚刚打印出两条线,所以我可以看到发生了什么。 打印$ pword行很好,但打印$ pword_match给我一个空白。

encrypt_decrypt()函数:

<?php       
    function encrypt_decrypt($action, $string) {
    $output = false;

    $encrypt_method = "AES-256-CBC";
    $secret_key = $string;
    $secret_iv = "password";
    // hash
    $key = hash('sha256', $secret_key);

    // iv - encrypt method AES-256-CBC expects 16 bytes - else you will get a warning
    $iv = substr(hash('sha256', $secret_iv), 0, 16);

    if( $action == 'encrypt' ) {
        $output = openssl_encrypt($string, $encrypt_method, $key, 0, $iv);
        $output = base64_encode($output);
    }
    else if( $action == 'decrypt' ){
        $output = openssl_decrypt(base64_decode($string), $encrypt_method, $key, 0, $iv);
    }

    return $output;
}
?>

1 个答案:

答案 0 :(得分:1)

关于如何在服务器上处理密码,搜索示例代码,有数百个答案。

基本上,当第一次对密码进行哈希处理并将哈希值存储在服务器上时,会收到密码。当用户想要登录时,检索密码哈希,密码被哈希,然后比较哈希值。

请参阅:Safe Password Hashing

注意:加密密码意味着密钥位于服务器上,如果攻击者获得密码,则攻击者可以使用所有密码。如果您认为服务器是安全的,您就不必费心加密密码了。人们不能依赖服务器的安全性,但至少应该对服务器使用双因素身份验证。