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<?php
session_start();
include "db_conn.php";

if(isset($_POST['uname']) && isset($_POST['password'])) {

    function validate($data) {
        $data = trim($data);
        $data = stripslashes($data);
        $data = htmlspecialchars($data);
        return data;
    }
}

$uname = validate($_POST['uname']);
$pass = validate($_POST['password']);

if(empty($uname)) {
    header ("Location: index.php?error=User Name is Required");
    exit();
}
else if(empty($pass)) 
    header("Location: index.php?error=Password is Required");
    exit() 


$sql = "SELECT * FROM users WHERE user_name='$uname' AND password='$pass'";

$result = mysqli_query($conn, $sql);

if(mysqli_num_rows($result) === 1) {
    $row = mysqli_fetch_assoc($result);
    if($row['user_name'] === $uname && $row['password'] === $pass) {
        echo "Logged In!";
        $_SESSION['user_name'] = $row['user_name'];
        $_SESSION['name'] = $row['name'];
        $_SESSION['id'] = $row['id'];
        header("Location: home.php");
        exit();
    }
    else{  
        header("Location: index.php?error=Incorrect User Name or Password");
        exit(); 
    }    
}
else {
    header("Location: index.php");
    exit();
}


What I have tried:

Ive looked at line 27 as it shows the error is there but im stumped? No idea what the unexpected variable is. Plz help me.

Ed
Posted
Updated 25-Feb-23 5:55am
Comments
Richard Deeming 27-Feb-23 5:26am    
In addition to the SQL Injection[^] vulnerability, you are also storing your users' passwords in plain text. Don't do that!
Secure Password Authentication Explained Simply[^]
Salted Password Hashing - Doing it Right[^]

PHP even has built-in functions to help you do the right thing:
PHP: password_hash[^]
PHP: password_verify[^]

1 solution

It's a missing semicolon on the line above:
    header("Location: index.php?error=Password is Required");
    exit() 
          ^

$sql = "SELECT * FROM users WHERE user_name='$uname' AND password='$pass'";
But ... You should expect to get syntax errors every day, probably many times a day while you are coding - we all do regardless of how much experience we have! Sometimes, we misspell a variable, or a keyword; sometimes we forget to close a string or a code block. Sometimes the cat walks over your keyboard and types something really weird. Sometimes we just forget how many parameters a method call needs.

We all make mistakes.

And because we all do it, we all have to fix syntax errors - and it's a lot quicker to learn how and fix them yourself than to wait for someone else to fix them for you! So invest a little time in learning how to read error messages, and how to interpret your code as written in the light of what the compiler is telling you is wrong - it really is trying to be helpful!

So read this: How to Write Code to Solve a Problem, A Beginner's Guide Part 2: Syntax Errors[^] - it should help you next time you get a compilation error!

And another thing you need to know - never do SQL like that! Never concatenate strings to build a SQL command. It leaves you wide open to accidental or deliberate SQL Injection attack which can destroy your entire database. Always use Parameterized queries instead.

When you concatenate strings, you cause problems because SQL receives commands like:
SQL
SELECT * FROM MyTable WHERE StreetAddress = 'Baker's Wood'
The quote the user added terminates the string as far as SQL is concerned and you get problems. But it could be worse. If I come along and type this instead: "x';DROP TABLE MyTable;--" Then SQL receives a very different command:
SQL
SELECT * FROM MyTable WHERE StreetAddress = 'x';DROP TABLE MyTable;--'
Which SQL sees as three separate commands:
SQL
SELECT * FROM MyTable WHERE StreetAddress = 'x';
A perfectly valid SELECT
SQL
DROP TABLE MyTable;
A perfectly valid "delete the table" command
SQL
--'
And everything else is a comment.
So it does: selects any matching rows, deletes the table from the DB, and ignores anything else.

So ALWAYS use parameterized queries! Or be prepared to restore your DB from backup frequently. You do take backups regularly, don't you?
 
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