


How Does PHP's `password_hash` Securely Handle Passwords and Verify Logins?
Dec 24, 2024 am 03:33 AMHow to Use PHP's password_hash to Securely Hash and Verify Passwords
In an effort to enhance the security of your login script, you've encountered password_hash and are seeking clarification on its functionality. Here's a detailed breakdown to answer your questions:
Is Salt Generated by password_hash?
Yes, when using password_hash, a unique salt is automatically generated for each password. This is a cryptographically secure random value that is combined with the password before hashing. Salt prevents rainbow table attacks, making it more difficult to crack passwords.
Storing Salt Separately: A Misconception
Your suggestion to have separate salts in the file and database is based on a misconception. Storing salts is never recommended for security reasons. The point of using a salt is to make it difficult for attackers to determine the underlying hash function and password. Separating salts defeats that purpose.
The Correct Approach:
- Hash the Password: Use password_hash to generate a salted hash from the user's password. Store the hash in the database, ensuring it's long enough (at least 60 characters).
- Verify Login: When a user attempts to log in, compare the entered password with the hashed password in the database using password_verify. This ensures that the entered password matches the original password, preventing unauthorized access.
Example Code:
$password = $_POST['password']; $hashed_password = password_hash($password, PASSWORD_DEFAULT); // Store $hashed_password in the database // For login verification: if (password_verify($password, $hashed_password)) { // User provided the correct password } else { // Password mismatch }
Conclusion:
By understanding the proper use of password_hash, you can build secure login systems without needing to implement complex salt generation mechanisms. It generates salted hashes, prevents rainbow table attacks, and ensures the privacy and integrity of user passwords.
The above is the detailed content of How Does PHP's `password_hash` Securely Handle Passwords and Verify Logins?. For more information, please follow other related articles on the PHP Chinese website!

Hot AI Tools

Undress AI Tool
Undress images for free

Undresser.AI Undress
AI-powered app for creating realistic nude photos

AI Clothes Remover
Online AI tool for removing clothes from photos.

Clothoff.io
AI clothes remover

Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

Notepad++7.3.1
Easy-to-use and free code editor

SublimeText3 Chinese version
Chinese version, very easy to use

Zend Studio 13.0.1
Powerful PHP integrated development environment

Dreamweaver CS6
Visual web development tools

SublimeText3 Mac version
God-level code editing software (SublimeText3)

Hot Topics









TosettherighttimezoneinPHP,usedate_default_timezone_set()functionatthestartofyourscriptwithavalididentifiersuchas'America/New_York'.1.Usedate_default_timezone_set()beforeanydate/timefunctions.2.Alternatively,configurethephp.inifilebysettingdate.timez

ToquicklytestaPHPcodesnippet,useanonlinePHPsandboxlike3v4l.orgorPHPize.onlineforinstantexecutionwithoutsetup;runcodelocallywithPHPCLIbycreatinga.phpfileandexecutingitviatheterminal;optionallyusephp-rforone-liners;setupalocaldevelopmentenvironmentwith

Upgrading the PHP version is actually not difficult, but the key lies in the operation steps and precautions. The following are the specific methods: 1. Confirm the current PHP version and running environment, use the command line or phpinfo.php file to view; 2. Select the suitable new version and install it. It is recommended to install it with 8.2 or 8.1. Linux users use package manager, and macOS users use Homebrew; 3. Migrate configuration files and extensions, update php.ini and install necessary extensions; 4. Test whether the website is running normally, check the error log to ensure that there is no compatibility problem. Follow these steps and you can successfully complete the upgrade in most situations.

TosetupaPHPdevelopmentenvironmentonLinux,installPHPandrequiredextensions,setupawebserverlikeApacheorNginx,testwithaPHPfile,andoptionallyinstallMySQLandComposer.1.InstallPHPandextensionsviapackagemanager(e.g.,sudoaptinstallphpphp-mysqlphp-curlphp-mbst

To set up a PHP development environment, you need to select the appropriate tools and install the configuration correctly. ①The most basic PHP local environment requires three components: the web server (Apache or Nginx), the PHP itself and the database (such as MySQL/MariaDB); ② It is recommended that beginners use integration packages such as XAMPP or MAMP, which simplify the installation process. XAMPP is suitable for Windows and macOS. After installation, the project files are placed in the htdocs directory and accessed through localhost; ③MAMP is suitable for Mac users and supports convenient switching of PHP versions, but the free version has limited functions; ④ Advanced users can manually install them by Homebrew, in macOS/Linux systems

To merge two PHP arrays and keep unique values, there are two main methods. 1. For index arrays or only deduplication, use array_merge and array_unique combinations: first merge array_merge($array1,$array2) and then use array_unique() to deduplicate them to finally get a new array containing all unique values; 2. For associative arrays and want to retain key-value pairs in the first array, use the operator: $result=$array1 $array2, which will ensure that the keys in the first array will not be overwritten by the second array. These two methods are applicable to different scenarios, depending on whether the key name is retained or only the focus is on

TopreventCSRFattacksinPHP,implementanti-CSRFtokens.1)Generateandstoresecuretokensusingrandom_bytes()orbin2hex(random_bytes(32)),savethemin$_SESSION,andincludetheminformsashiddeninputs.2)ValidatetokensonsubmissionbystrictlycomparingthePOSTtokenwiththe

To determine the strength of the password, it is necessary to combine regular and logical processing. The basic requirements include: 1. The length is no less than 8 digits; 2. At least containing lowercase letters, uppercase letters, and numbers; 3. Special character restrictions can be added; in terms of advanced aspects, continuous duplication of characters and incremental/decreasing sequences need to be avoided, which requires PHP function detection; at the same time, blacklists should be introduced to filter common weak passwords such as password and 123456; finally it is recommended to combine the zxcvbn library to improve the evaluation accuracy.
