How to Build a Password Strength Checker with Breach Alerts Chrome Extension

Simple Summary

A powerful Chrome extension that checks password strength in real-time and alerts users to potential breaches, enhancing online security effortlessly.

Product Requirements Document (PRD)

Goals:

• Create a user-friendly Chrome extension for password strength checking
• Implement real-time password analysis
• Integrate breach alert functionality
• Ensure secure handling of user data

Target Audience:

• Security-conscious internet users
• Individuals managing multiple online accounts
• Businesses looking to enhance employee password practices

Key Features:

1. Real-time password strength meter
2. Password breach checking against known databases
3. Customizable password criteria settings
4. Secure local storage of user preferences
5. Notifications for weak passwords and potential breaches

User Requirements:

• Easy installation and setup process
• Intuitive interface for password strength feedback
• Clear alerts for potential security risks
• Option to customize strength criteria
• Privacy-focused design with minimal data collection

User Flows

1. Extension Installation and Setup:

   • User installs the Chrome extension
   • User sets up initial preferences (optional)
   • Extension activates automatically on password fields

2. Password Strength Check:

   • User begins typing a password in a supported field
   • Extension analyzes password in real-time
   • Visual feedback displays current strength level
   • Suggestions for improvement appear if necessary

3. Breach Alert Process:

   • User enters a password
   • Extension checks against breach database
   • If a match is found, user receives an alert
   • Alert provides guidance on next steps (e.g., change password)

Technical Specifications

• Frontend: React for UI components
• Backend: Node.js for API and server-side logic
• Database: PostgreSQL for storing user settings and encrypted data
• API: RESTful design for communication between extension and server
• Security: HTTPS, encryption for sensitive data, secure storage practices
• Chrome Extension API: For browser integration and UI injection
• Password Strength Algorithm: zxcvbn or similar for comprehensive analysis
• Breach checking: Integration with Have I Been Pwned API or similar service

API Endpoints

• POST /api/register: User registration
• POST /api/login: User authentication
• GET /api/settings: Retrieve user settings
• PUT /api/settings: Update user settings
• POST /api/check-password: Submit password for strength analysis
• GET /api/check-breach: Check if password has been involved in known breaches

Database Schema

Users Table:

• id (PK)
• email
• hashed_password
• created_at
• updated_at

Settings Table:

• id (PK)
• user_id (FK to Users)
• min_password_length
• require_special_chars
• require_numbers
• created_at
• updated_at

PasswordChecks Table:

• id (PK)
• user_id (FK to Users)
• strength_score
• checked_at

File Structure

Implementation Plan

1. Project Setup (1-2 days)

   • Initialize React project for Chrome extension
   • Set up Node.js backend
   • Configure PostgreSQL database

2. Core Extension Functionality (3-4 days)

   • Implement password field detection
   • Develop real-time strength analysis algorithm
   • Create visual strength meter component

3. Backend Development (2-3 days)

   • Set up API endpoints
   • Implement user authentication
   • Develop settings management system

4. Breach Alert Integration (2-3 days)

   • Integrate with breach checking API
   • Implement alert system in extension

5. User Interface and Experience (3-4 days)

   • Design and implement options page
   • Create popup interface
   • Ensure responsive design across different websites

6. Security and Privacy Features (2-3 days)

   • Implement encryption for sensitive data
   • Set up secure communication between extension and server

7. Testing and Refinement (3-4 days)

   • Conduct thorough testing of all features
   • Perform security audits
   • Optimize performance and user experience

8. Documentation and Deployment Preparation (1-2 days)

   • Write user documentation
   • Prepare for Chrome Web Store submission

Deployment Strategy

1. Backend Deployment:

   • Deploy Node.js server to a cloud platform (e.g., Heroku, AWS Elastic Beanstalk)
   • Set up PostgreSQL database on a managed service (e.g., Amazon RDS, Heroku Postgres)

2. Frontend Deployment:

   • Package Chrome extension for distribution
   • Submit extension to Chrome Web Store for review and publication

3. Continuous Integration/Deployment:

   • Implement CI/CD pipeline using GitHub Actions or similar
   • Automate testing and deployment processes

4. Monitoring and Maintenance:

   • Set up logging and monitoring tools (e.g., Sentry, New Relic)
   • Establish a system for regular security updates and patches

Design Rationale

The design focuses on creating a seamless, secure user experience while providing robust password management features. React was chosen for its component-based architecture, allowing for easy maintenance and scalability of the extension's UI. Node.js on the backend provides a JavaScript-based ecosystem, simplifying development across frontend and backend.

The use of a PostgreSQL database ensures data integrity and allows for complex queries if needed for future feature expansions. RESTful API design principles are employed for clear, stateless communication between the extension and server.

Security is paramount, hence the inclusion of encryption utilities and secure storage practices. The integration with established breach checking services leverages existing databases for comprehensive protection.

The file structure separates concerns clearly, promoting maintainability and allowing for easy addition of new features. The implementation plan prioritizes core functionality early, allowing for iterative improvements and refinements based on initial user feedback.