checkmark

PHP

Introduction to PHP

What is PHP? Advantages of PHP How PHP Works (Server-Side Scripting) Setting Up a PHP Development Environment

Basics of PHP

Writing Your First PHP Script Comments in PHP Variables and Data Types Constants Operators in PHP

Control Structures

Conditional Statements (if, else, elseif) Switch Statement Loops (for, while, do-while) Break and Continue Statements

Functions in PHP

Introduction to Functions Defining Functions Function Parameters and Return Values Scope of Variables (Local and Global) Built-In Functions vs. User-Defined Functions

Arrays in PHP

Introduction to Arrays Indexed Arrays Associative Arrays Multidimensional Arrays Array Functions

Working with Forms

Creating HTML Forms Submitting Form Data Handling Form Data in PHP Form Validation and Sanitization

Working with Files and Directories

File Handling in PHP (Opening, Reading, Writing) Uploading Files in PHP Working with Directories File I/O Operations

Databases and MySQL

Setting Up a MySQL Database Connecting to a Database Querying a Database (SELECT, INSERT, UPDATE, DELETE) Prepared Statements Handling Database Errors

PHP Sessions and Cookies

Introduction to Sessions Cookies in PHP

Object-Oriented Programming (OOP)

Introduction to Object-Oriented Programming (OOP) in PHP Classes and Objects Constructors and Destructors Inheritance and Polymorphism Encapsulation and Abstraction

Error Handling and Exception Handling

Handling Errors in PHP Custom Error Handling Introduction to Exceptions Try, Catch, Finally Blocks Creating Custom Exceptions

PHP and Web Security

SQL Injection Prevention Cross-Site Scripting (XSS) Prevention Cross-Site Request Forgery (CSRF) Protection Data Validation and Sanitization Password Hashing PHP Security Checklist

PHP Frameworks and CMS

Introduction to PHP Frameworks (e.g., Laravel, Symfony) Overview of PHP Content Management Systems (e.g., WordPress, Joomla)

Advanced PHP Topics

RESTful APIs with PHP Working with JSON Data Creating Web Services Composer and Package Management Debugging PHP Code Performance Optimization Best Practices in PHP Development
menu Back to Edkool

Password Hashing

Password Hashing in PHP

Password hashing is a crucial aspect of security when working with user authentication in PHP applications. Storing plaintext passwords is a significant security risk, and it's essential to use proper hashing techniques to protect user credentials. Here's how to implement password hashing in PHP:

1. Using password_hash() and password_verify():

PHP provides the password_hash() function to securely hash passwords and the password_verify() function to verify them. It uses the bcrypt algorithm, which is suitable for password storage.

Hashing a Password:

$plainPassword = 'user_password';
$hashedPassword = password_hash($plainPassword, PASSWORD_DEFAULT);

// Store $hashedPassword in your database

Verifying a Password:

$hashedPasswordFromDatabase = '...'; // Retrieve from the database
$userInputPassword = 'user_password'; // User input

if (password_verify($userInputPassword, $hashedPasswordFromDatabase)) {
    // Password is correct
} else {
    // Password is incorrect
}

2. Choosing a Suitable Algorithm:

You can specify a specific algorithm and cost (work factor) for password hashing if you prefer not to use the default algorithm. The default algorithm is currently bcrypt.

$options = [
    'cost' => 12, // The cost factor (higher is slower but more secure)
];

$hashedPassword = password_hash($plainPassword, PASSWORD_BCRYPT, $options);

3. Salting Passwords:

The password_hash() function handles the generation of a secure salt automatically. A unique salt is used for each password hash, making it difficult for attackers to use precomputed rainbow tables.

4. Storing Hashed Passwords:

Store the hashed passwords in your database, not plaintext passwords. This ensures that even if the database is compromised, the actual passwords remain secure.

5. Regularly Rehashing Passwords:

To enhance security, consider rehashing passwords periodically. This is especially important when you update your password hashing algorithm or increase the cost factor. You can use password_needs_rehash() to determine if a password needs rehashing.

if (password_needs_rehash($hashedPasswordFromDatabase, PASSWORD_DEFAULT)) {
    $newHashedPassword = password_hash($userInputPassword, PASSWORD_DEFAULT);
    // Update the hashed password in the database
}

6. Handling Password Reset and Recovery:

When implementing password reset or recovery features, ensure that the user's original password is not exposed. Instead, allow the user to set a new password, and hash it securely before storing it in the database.

Password hashing is a critical component of user authentication and security in PHP applications. It protects user credentials even if the database is compromised. By using the built-in functions like password_hash() and password_verify(), you can easily implement robust and secure password hashing mechanisms.

Previous Data Validation and Sanitization
Next PHP Security Checklist