Skip to content

Latest commit

 

History

History
251 lines (189 loc) · 14.7 KB

sec-design.md

File metadata and controls

251 lines (189 loc) · 14.7 KB

Project Design Document: clipboard.js

BUSINESS POSTURE

clipboard.js is a small, open-source library that provides a modern approach to copying text to the clipboard. It's designed to be lightweight and dependency-free. The project's primary goal is to simplify the often-cumbersome process of implementing copy-to-clipboard functionality in web applications, enhancing user experience.

Business Priorities:

  • Ease of Use: Provide a simple and intuitive API for developers.
  • Cross-Browser Compatibility: Ensure consistent behavior across different web browsers.
  • Lightweight and Dependency-Free: Minimize the library's footprint and avoid external dependencies.
  • Maintainability: Keep the codebase clean, well-documented, and easy to maintain.
  • Community Engagement: Foster a welcoming community and encourage contributions.

Business Risks:

  • Browser Compatibility Issues: Changes in browser APIs or security models could break functionality.
  • Security Vulnerabilities: Although primarily a client-side library, potential vulnerabilities could be exploited, especially if misused in conjunction with user-supplied data.
  • Maintenance Overhead: As an open-source project, maintaining the library and addressing issues relies on community contributions and the availability of maintainers.
  • Lack of Adoption: If developers don't find the library useful or if better alternatives emerge, the project could become obsolete.

SECURITY POSTURE

Existing Security Controls:

  • security control: Input Sanitization: The library appears to sanitize input to some extent by focusing on text content, mitigating potential injection risks. (Implicit in the library's functionality).
  • security control: No eval(): The library avoids using eval(), which is a common source of security vulnerabilities. (Review of the source code).
  • security control: Limited Scope: The library's scope is limited to copying text, reducing the attack surface. (Design of the library).
  • security control: Open Source: The code is publicly available for review and scrutiny, allowing for community-driven security audits. (GitHub repository).

Accepted Risks:

  • accepted risk: Client-Side Manipulation: As a client-side library, it's inherently susceptible to manipulation by malicious users. This is a fundamental limitation of client-side code.
  • accepted risk: Browser-Specific Exploits: Undiscovered browser-specific vulnerabilities could potentially be exploited, although this is outside the direct control of the library.
  • accepted risk: Reliance on Browser APIs: The library depends on browser APIs (like document.execCommand and Clipboard API), and changes or deprecations in these APIs could affect functionality and potentially introduce security concerns.

Recommended Security Controls:

  • security control: Content Security Policy (CSP) Integration: Provide guidance in the documentation on how to integrate clipboard.js with a website's CSP to further mitigate potential XSS risks.
  • security control: Subresource Integrity (SRI) Support: If distributing via CDN, provide SRI hashes to ensure the integrity of the library file.
  • security control: Security Audits: Encourage regular security audits by independent researchers or security professionals.

Security Requirements:

  • Authentication: Not applicable, as the library doesn't handle user authentication.
  • Authorization: Not applicable, as the library doesn't manage user permissions or roles.
  • Input Validation:
    • The library should primarily handle plain text. Any handling of HTML or other rich text formats should be carefully scrutinized for potential XSS vulnerabilities.
    • If the library provides options for customizing the copied text (e.g., through event listeners), ensure that these options are properly sanitized.
  • Cryptography: Not directly applicable, as the library's primary function doesn't involve encryption. However, if the library were to handle sensitive data (which it shouldn't), proper encryption mechanisms should be considered.
  • Data Sensitivity: The library should treat all copied data as potentially sensitive, even if it appears to be plain text.

DESIGN

C4 CONTEXT

graph LR
    User["User (Web Browser)"] -- "Clicks on a copy button" --> ClipboardJS["Clipboard.js Library"]
    ClipboardJS -- "Copies text to clipboard" --> SystemClipboard["System Clipboard"]
    ClipboardJS -- "Uses" --> BrowserAPI["Browser API (document.execCommand, Clipboard API)"]
Loading

Element Descriptions:

  • Element: User

    • Name: User
    • Type: Person
    • Description: A person interacting with a web page that uses clipboard.js.
    • Responsibilities: Interacts with the web page, clicks on elements that trigger copy-to-clipboard functionality.
    • Security controls: Relies on browser security mechanisms and website security implementation.

  • Element: Clipboard.js Library

    • Name: Clipboard.js Library
    • Type: Software System
    • Description: The clipboard.js library, embedded within a web page.
    • Responsibilities: Provides an API for copying text to the system clipboard. Handles events triggered by user interaction.
    • Security controls: Input sanitization, avoidance of eval(), limited scope of functionality.

  • Element: System Clipboard

    • Name: System Clipboard
    • Type: Software System
    • Description: The operating system's clipboard.
    • Responsibilities: Stores data copied by applications, allowing it to be pasted elsewhere.
    • Security controls: Managed by the operating system; clipboard.js has no direct control.

  • Element: Browser API

    • Name: Browser API
    • Type: Software System
    • Description: The browser's built-in APIs for interacting with the clipboard (e.g., document.execCommand, Clipboard API).
    • Responsibilities: Provides the underlying mechanism for copying text to the clipboard.
    • Security controls: Managed by the browser vendor; clipboard.js relies on the security of these APIs.

C4 CONTAINER

graph LR
    User["User (Web Browser)"] -- "Clicks on a copy button" --> WebPage["Web Page (HTML, CSS, JS)"]
    WebPage -- "Uses" --> ClipboardJS["Clipboard.js Library"]
    ClipboardJS -- "Copies text" --> BrowserAPI["Browser API (document.execCommand, Clipboard API)"]
    BrowserAPI -- "Access" --> SystemClipboard["System Clipboard"]
Loading

Element Descriptions:

  • Element: User

    • Name: User
    • Type: Person
    • Description: A person interacting with a web page that uses clipboard.js.
    • Responsibilities: Interacts with the web page, clicks on elements that trigger copy-to-clipboard functionality.
    • Security controls: Relies on browser security mechanisms and website security implementation.

  • Element: Web Page

    • Name: Web Page
    • Type: Container: Web Application
    • Description: The web page that embeds and uses the clipboard.js library.
    • Responsibilities: Presents content to the user, includes and initializes clipboard.js, defines elements that trigger copy actions.
    • Security controls: Website's overall security implementation (e.g., CSP, XSS protection).

  • Element: Clipboard.js Library

    • Name: Clipboard.js Library
    • Type: Container: JavaScript Library
    • Description: The clipboard.js library, embedded within a web page.
    • Responsibilities: Provides an API for copying text to the system clipboard. Handles events triggered by user interaction.
    • Security controls: Input sanitization, avoidance of eval(), limited scope of functionality.

  • Element: Browser API

    • Name: Browser API
    • Type: Container: Browser API
    • Description: The browser's built-in APIs for interacting with the clipboard (e.g., document.execCommand, Clipboard API).
    • Responsibilities: Provides the underlying mechanism for copying text to the clipboard.
    • Security controls: Managed by the browser vendor; clipboard.js relies on the security of these APIs.

  • Element: System Clipboard

    • Name: System Clipboard
    • Type: Container: Operating System Component
    • Description: The operating system's clipboard.
    • Responsibilities: Stores data copied by applications, allowing it to be pasted elsewhere.
    • Security controls: Managed by the operating system; clipboard.js has no direct control.

DEPLOYMENT

clipboard.js is a client-side JavaScript library, and its "deployment" typically involves including it in a web page. There are several ways to do this:

  1. Direct Download: Download the library file (clipboard.min.js) and include it in the project's directory structure.
  2. CDN (Content Delivery Network): Link to the library hosted on a CDN, such as jsDelivr or cdnjs. This is the recommended approach for most users.
  3. Package Manager (npm, yarn): Install the library as a dependency using a package manager. This is common for projects using build tools like Webpack or Parcel.

Chosen Deployment Method (CDN):

graph LR
    Developer["Developer"] -- "Writes code" --> WebServer["Web Server"]
    WebServer -- "Serves HTML" --> UserBrowser["User's Browser"]
    UserBrowser -- "Requests clipboard.min.js" --> CDN["CDN (e.g., jsDelivr)"]
    CDN -- "Serves clipboard.min.js" --> UserBrowser
    UserBrowser -- "Executes clipboard.js" --> SystemClipboard["System Clipboard"]
Loading

Element Descriptions:

  • Element: Developer

    • Name: Developer
    • Type: Person
    • Description: The developer integrating clipboard.js into their web application.
    • Responsibilities: Writes the HTML, CSS, and JavaScript code for the web page, includes clipboard.js, and configures its usage.
    • Security controls: Follows secure coding practices.

  • Element: Web Server

    • Name: Web Server
    • Type: Software System
    • Description: The server hosting the web application.
    • Responsibilities: Serves the HTML, CSS, JavaScript, and other assets to the user's browser.
    • Security controls: Standard web server security measures (e.g., HTTPS, firewalls).

  • Element: User's Browser

    • Name: User's Browser
    • Type: Software System
    • Description: The user's web browser.
    • Responsibilities: Renders the web page, executes JavaScript code (including clipboard.js), interacts with the system clipboard.
    • Security controls: Browser's built-in security mechanisms.

  • Element: CDN

    • Name: CDN
    • Type: Software System
    • Description: A Content Delivery Network (e.g., jsDelivr, cdnjs).
    • Responsibilities: Hosts and serves static assets like clipboard.min.js, providing fast and reliable delivery.
    • Security controls: CDN provider's security measures (e.g., HTTPS, DDoS protection).

  • Element: System Clipboard

    • Name: System Clipboard
    • Type: Software System
    • Description: The operating system's clipboard.
    • Responsibilities: Stores data copied by applications.
    • Security controls: Managed by the operating system.

BUILD

clipboard.js uses a build process to create the minified version of the library (clipboard.min.js) from the source files. This process typically involves:

  1. Source Code (src/): The core JavaScript code for the library.
  2. Build Tools (npm scripts, Gulp): The project uses npm scripts and Gulp as a task runner to automate the build process.
  3. Minification (UglifyJS): UglifyJS is used to minify the JavaScript code, reducing its file size for faster loading in browsers.
  4. Testing (Mocha, Karma): The project includes unit tests using Mocha and Karma to ensure the library functions correctly.
  5. Distribution (dist/): The build process generates the minified clipboard.min.js file in the dist/ directory.
graph LR
    Developer["Developer"] -- "Writes code" --> SourceCode["Source Code (src/)"]
    SourceCode -- "npm run build" --> BuildTools["Build Tools (npm scripts, Gulp)"]
    BuildTools -- "Minification (UglifyJS)" --> MinifiedCode["Minified Code (clipboard.min.js)"]
    BuildTools -- "Testing (Mocha, Karma)" --> TestResults["Test Results"]
    MinifiedCode -- "Distribution" --> DistFolder["dist/ Folder"]
Loading

Security Controls in Build Process:

  • security control: Dependency Management: npm is used to manage dependencies, allowing for tracking and updating of libraries used in the build process.
  • security control: Linting: The project likely uses a linter (although not explicitly mentioned, it's standard practice) to enforce code style and identify potential errors.
  • security control: Testing: Automated tests help ensure the library functions as expected and can catch regressions introduced by changes.
  • security control: Build Automation: The build process is automated using npm scripts and Gulp, reducing the risk of manual errors.

RISK ASSESSMENT

Critical Business Processes:

  • Providing a seamless copy-to-clipboard experience for users of web applications that integrate clipboard.js.
  • Maintaining the library's reputation as a reliable and secure solution for copy-to-clipboard functionality.

Data Protection:

  • Data Sensitivity: The library primarily handles text data copied by the user. While this data is often not highly sensitive, it could include passwords, personal information, or other confidential data, depending on the context where clipboard.js is used. The library itself does not store or transmit this data; it only facilitates copying it to the system clipboard.
  • Data to Protect: The primary data to protect is the integrity of the library itself (preventing malicious modifications) and ensuring it doesn't introduce vulnerabilities into applications that use it.

QUESTIONS & ASSUMPTIONS

Questions:

  • Are there any specific compliance requirements (e.g., GDPR, CCPA) that apply to the use of clipboard.js in applications? (Assumption: No specific compliance requirements beyond general data privacy best practices.)
  • Are there any plans to extend the functionality of clipboard.js beyond plain text copying? (Assumption: The library will primarily focus on plain text.)
  • What is the process for reporting and addressing security vulnerabilities discovered in clipboard.js? (Assumption: There is a process for responsible disclosure, likely through GitHub issues or a dedicated security contact.)

Assumptions:

  • BUSINESS POSTURE: The primary goal is to provide a simple, lightweight, and reliable copy-to-clipboard solution.
  • SECURITY POSTURE: The library is used in a wide range of web applications, and developers integrating it are responsible for the overall security of their applications.
  • DESIGN: The library's design prioritizes simplicity and cross-browser compatibility. The build process is automated and includes testing. The deployment model relies on standard web development practices (including the library via <script> tag).