Viewed   519 times

I'm trying to me a page more secure and I started with the password encrypting part of it. I'm trying to implement password_hash + password verify, but so far I've been unsuccessful to make the whole thing work. So, here it is in my login area:

$username = mysqli_real_escape_string($connection, $_POST['username']);

$password = mysqli_real_escape_string($connection, $_POST['password']);

$query = "SELECT username, password FROM `users` WHERE username='$username' and user_enabled='1'";
$result = mysqli_query($connection, $query) or die(mysqli_error($connection));
if($row = mysqli_fetch_assoc($result)) { $dbpassword = $row['password']; }

if(password_verify($password, $dbpassword)) {
    echo "Successful login";
    echo "Invalid Login Credentials.";

I always get Invalid Login Credentials.

When I modify the new password for the user, I am doing the following:

$pass = mysqli_real_escape_string($connection, $_POST['password']);
$options = [ 'cost' => 10,
             'salt' => mcrypt_create_iv(22, MCRYPT_DEV_URANDOM),
$password = password_hash($pass,  PASSWORD_BCRYPT, $options)."n";

$query = "UPDATE users 
          SET `password` = '".$password."'
          WHERE id = ".$_POST['user_id']."

$result = mysqli_query($connection, $query) or die(mysqli_error($connection));

password in database is VARCHAR(255), and it is storing something like:


What am I doing wrong here?



The n in the following line, is embedding a linebreak, (Edit: one that cannot be included in the user inputted password).

$password = password_hash($pass,  PASSWORD_BCRYPT, $options)."n";

and you need to delete it and start over with a new hash.

Jay Blanchard, a member here on Stack submitted a note about it not too long also in the password_hash() manual, which is something that he and I actually talked about.

Be care when using the example from the documentation which concatenates a newline character n to the end of the hash, i.e.:

echo password_hash("rasmuslerdorf", PASSWORD_DEFAULT)."n";

People are storing the hash with the concatenated newline and consequently password_verify() will fail.

Another option would be to use trim(); that also works (at the moment of hashing).

$password = password_hash($pass,  PASSWORD_BCRYPT, $options)."n";
$password = trim($password);
// Store in db after

Yet you still need to start over by clearing the old hash(es) and creating new ones.

Do keep in mind though, that you shouldn't escape passwords.

One such as 123'abc (being perfectly valid) will be modified to 123'abc by real_escape_string(); it's not needed. password_verify() takes care of that, security-wise.

Tuesday, October 4, 2022

The problem described here was solved by me quite a long time ago but I don't really remember what was the main reason that uploads weren't working. There were multiple things that needed fixing so the upload could work. I have created checklist that might help others having similar problems and I will edit it to make it as helpful as possible. As I said before on chat, I was working on embedded system, so some points may be skipped on non-embedded systems.

  • Check upload_tmp_dir in php.ini. This is directory where PHP stores temporary files while uploading.

  • Check open_basedir in php.ini. If defined it limits PHP read/write rights to specified path and its subdirectories. Ensure that upload_tmp_dir is inside this path.

  • Check post_max_size in php.ini. If you want to upload 20 Mbyte files, try something a little bigger, like post_max_size = 21M. This defines largest size of POST message which you are probably using during upload.

  • Check upload_max_filesize in php.ini. This specifies biggest file that can be uploaded.

  • Check memory_limit in php.ini. That's the maximum amount of memory a script may consume. It's quite obvious that it can't be lower than upload size (to be honest I'm not quite sure about it-PHP is probably buffering while copying temporary files).

  • Ensure that you're checking the right php.ini file that is one used by PHP on your webserver. The best solution is to execute script with directive described here (php_ini_loaded_file function)

  • Check what user php runs as (See here how to do it: How to check what user php is running as? ). I have worked on different distros and servers. Sometimes it is apache, but sometimes it can be root. Anyway, check that this user has rights for reading and writing in the temporary directory and directory that you're uploading into. Check all directories in the path in case you're uploading into subdirectory (for example /dir1/dir2/-check both dir1 and dir2.

  • On embedded platforms you sometimes need to restrict writing to root filesystem because it is stored on flash card and this helps to extend life of this card. If you are using scripts to enable/disable file writes, ensure that you enable writing before uploading.

  • I had serious problems with PHP >5.4 upload monitoring based on sessions (as described here ) on some platforms. Try something simple at first (like here: ). If it works, you can try more sophisticated mechanisms.

  • If you make any changes in php.ini remember to restart server so the configuration will be reloaded.

Sunday, December 18, 2022

So if anyone ever stumbles on this forum because they are having the same issue let me explain what and why it went wrong.

If you include a function not in your directory(e.g c:// or file://) but instead include using http. The include can only return what was echoed in the file, but something like a variable or function will not be shown. So always include functions and variables through a directory

Sunday, October 2, 2022

Ignoring the issues with your database statements for now, I'll answer the question regarding password_hash.

In short, no, that is not how you do it. You do not want to store the salt alone, you should be storing both the hash and salt, and then using both to verify the password. password_hash returns a string containing both.

The password_hash function returns a string that contains both the hash and the salt. So:

$hashAndSalt = password_hash($password, PASSWORD_BCRYPT);
// Insert $hashAndSalt into database against user

Then to verify:

// Fetch hash+salt from database, place in $hashAndSalt variable
// and then to verify $password:
if (password_verify($password, $hashAndSalt)) {
   // Verified

Additionally, as the comments suggest, if you're interested in security you may want to look at mysqli (ext/mysql is deprecated in PHP5.5), and also this article on SQL injection:

Monday, October 24, 2022

"I was wondering if there is an even better way to hash passwords in PHP 7+ then password_hash. Is password_hash good enough?"

Yes it is safe enough, and yes there is a better/safer way. As of PHP 7.2, Argon2 is part of a newly implemented (hashing) method that won the Password Hashing Competition which offers a more robust method, should you want to upgrade your version of PHP to 7.2.

The wiki on this states:

Argon2, the recommended password hashing algorithm by the Password Hashing Competition, is a modern algorithm for securely hashing passwords. Argon2 addresses several key downsides of existing algorithms in that it is designed for the highest memory filling rate, and effective use multiple computing units while still providing defense against tradeoff attacks. Unlike Bcrypt, which just takes a single cost factor, Argon2 is parameterized by three distinct factors:

  1. A memory cost that defines memory usage of the algorithm
  2. A time cost that defines the execution time of the algorithm and the number of iterations
  3. And a parallelism factor, which defines the number of parallel threads

You can also look into the following link which contains more information on Libsodium

The manual on also contains information on PASSWORD_ARGON2I.

The changelog states:

7.2.0 Support for Argon2 passwords using PASSWORD_ARGON2I was added.

If upgrading to PHP 7.2 is not an option, then you could increase the "cost".

Pulled from this answer and from the related post Generating Password Hash In PHP 5.5 And Setting Cost Option, and I quote:

Increasing the cost parameter by 1, doubles the needed time to calculate the hash value. The cost parameter is the logarithm (base-2) of the iteration count, that means:

$iterations = 2 ^ $cost;

You can also consult this other Q&A here on :

  • How does password_hash really work?
Thursday, December 15, 2022
Only authorized users can answer the search term. Please sign in first, or register a free account.
Not the answer you're looking for? Browse other questions tagged :