Secure Login Flows

1. Introduction

Secure login flows are critical in ensuring the confidentiality and integrity of user credentials. This lesson will focus on designing secure authentication mechanisms as part of the OWASP Top 10 security vulnerabilities.

2. Key Concepts

• Authentication: Verifying the identity of a user.
• Authorization: Granting permissions based on the user's identity.
• Session Management: Managing user sessions securely.
• Multi-Factor Authentication (MFA): Adding an extra layer of security beyond passwords.
• Secure Password Storage: Storing passwords using hashing algorithms.

3. Secure Login Flow

A secure login flow involves several steps:

graph TD;
    A[User enters credentials] --> B{Are credentials valid?};
    B -- Yes --> C[Authenticate user];
    B -- No --> D[Show error message];
    C --> E[Create session];
    E --> F[Redirect to user dashboard];
            

Following this flow ensures that user credentials are validated and sessions are managed securely.

4. Best Practices

• Use HTTPS to encrypt data in transit.
• Implement strong password policies.
• Use multi-factor authentication (MFA).
• Store passwords securely using hashing algorithms like bcrypt.
• Limit login attempts to prevent brute force attacks.
• Implement session timeouts for inactive sessions.
• Use CAPTCHAs to prevent automated login attempts.

5. Code Example

Here’s a simple example of secure password hashing using bcrypt in a Node.js application:

const bcrypt = require('bcrypt');

async function registerUser(password) {
    const saltRounds = 10;
    const hashedPassword = await bcrypt.hash(password, saltRounds);
    // Store hashedPassword in the database
}

async function loginUser(inputPassword, storedHashedPassword) {
    const match = await bcrypt.compare(inputPassword, storedHashedPassword);
    if (match) {
        // Grant access
    } else {
        // Deny access
    }
}
                

6. FAQ