Skip to content

Latest commit

 

History

History
331 lines (265 loc) · 16.5 KB

sec-design.md

File metadata and controls

331 lines (265 loc) · 16.5 KB

Okay, let's create a design document for the Django REST Framework (DRF) project, keeping in mind its purpose and potential security considerations.

BUSINESS POSTURE

Business Priorities and Goals:

  • Enable rapid development of robust and scalable RESTful APIs using Python and Django.
  • Provide a flexible and customizable toolkit for building APIs that meet diverse needs.
  • Maintain a high level of quality, reliability, and security for the framework.
  • Foster a strong and active open-source community around the project.
  • Reduce development time and cost for API creation.
  • Provide clear and comprehensive documentation.

Most Important Business Risks:

  • Vulnerabilities in the framework could lead to widespread exploitation of APIs built using it.
  • Inadequate documentation or support could hinder adoption and usage.
  • Lack of compatibility with evolving web standards and technologies could limit its usefulness.
  • Competition from other API frameworks could reduce its market share.
  • Failure to address community feedback and contributions could lead to project stagnation.

SECURITY POSTURE

Existing Security Controls:

  • security control: Authentication: Supports various authentication schemes, including Basic Auth, Session Auth, Token Auth, and OAuth2 (via third-party packages). Implemented in DRF documentation and code.
  • security control: Authorization: Provides permission classes to control access to API resources based on user roles and permissions. Implemented in DRF documentation and code.
  • security control: Throttling: Includes built-in mechanisms to limit API request rates, mitigating DoS attacks. Implemented in DRF documentation and code.
  • security control: Input Validation: Uses serializers to validate and sanitize data input, preventing common injection vulnerabilities. Implemented in DRF documentation and code.
  • security control: Output Encoding: Serializers handle data serialization, which can help prevent XSS vulnerabilities when configured correctly. Implemented in DRF documentation and code.
  • security control: CORS Handling: Supports Cross-Origin Resource Sharing (CORS) configuration to manage requests from different origins. Implemented in DRF documentation and code.
  • security control: Regular Security Audits: The project is likely subject to regular security audits and reviews by the community and maintainers, although this is not explicitly stated in the repository itself, it's a standard practice for mature open-source projects.
  • security control: Dependency Management: Uses tools like pip and requirements.txt to manage dependencies, allowing for vulnerability scanning. Implemented in project files.
  • security control: Secure by Default Settings: Encourages secure configurations and best practices in the documentation. Implemented in DRF documentation.

Accepted Risks:

  • accepted risk: Reliance on third-party packages for certain features (e.g., OAuth2) introduces potential risks if those packages have vulnerabilities.
  • accepted risk: Misconfiguration by developers using the framework can lead to security vulnerabilities in their applications.
  • accepted risk: Zero-day vulnerabilities in the framework or its dependencies may exist and could be exploited before patches are available.

Recommended Security Controls:

  • Implement a comprehensive security.txt file in the repository to provide clear instructions for reporting vulnerabilities.
  • Integrate automated security scanning tools (SAST, DAST, SCA) into the CI/CD pipeline.
  • Provide more explicit guidance and examples on secure coding practices within the documentation, particularly around handling sensitive data and preventing common web vulnerabilities.
  • Consider implementing a bug bounty program to incentivize security researchers to find and report vulnerabilities.

Security Requirements:

  • Authentication:

    • Support for strong authentication mechanisms (e.g., multi-factor authentication).
    • Secure storage of user credentials (e.g., hashing and salting passwords).
    • Protection against brute-force attacks.
    • Session management with secure cookies (HTTPOnly, Secure flags).

  • Authorization:

    • Fine-grained access control based on user roles and permissions.
    • Support for attribute-based access control (ABAC) or policy-based access control (PBAC).
    • Regular review and auditing of permissions.

  • Input Validation:

    • Strict validation of all input data using serializers.
    • Whitelist-based validation wherever possible.
    • Protection against common injection attacks (SQL injection, NoSQL injection, command injection).
    • Handling of file uploads securely (e.g., virus scanning, file type validation).

  • Cryptography:

    • Use of strong, industry-standard cryptographic algorithms.
    • Secure key management practices.
    • Protection of sensitive data in transit (HTTPS) and at rest (encryption).
    • Avoidance of custom cryptographic implementations.

DESIGN

C4 CONTEXT

graph LR
    User["User (Web Browser/Mobile App)"] -- "HTTPS" --> DRFProject["Django REST Framework Project"]
    DRFProject -- "Database Queries" --> Database["Database (e.g., PostgreSQL, MySQL)"]
    DRFProject -- "HTTP/HTTPS" --> ThirdPartyAPIs["Third-Party APIs (e.g., Payment Gateway, Social Media)"]
    DRFProject -- "Email Sending" --> EmailServer["Email Server (e.g., SMTP)"]
    Admin["Administrator"] -- "HTTPS" --> DRFProject
Loading

Element Descriptions:

  • Element:

    • Name: User (Web Browser/Mobile App)
    • Type: Person
    • Description: A user interacting with the API through a web browser or mobile application.
    • Responsibilities: Initiates requests to the API, views API responses.
    • Security controls: Uses HTTPS for secure communication.

  • Element:

    • Name: Django REST Framework Project
    • Type: Software System
    • Description: The core system built using the Django REST Framework.
    • Responsibilities: Handles API requests, processes data, interacts with other systems.
    • Security controls: Authentication, authorization, throttling, input validation, output encoding, CORS handling.

  • Element:

    • Name: Database (e.g., PostgreSQL, MySQL)
    • Type: Software System
    • Description: The database used to store the application's data.
    • Responsibilities: Stores and retrieves data.
    • Security controls: Database access controls, encryption at rest, regular backups.

  • Element:

    • Name: Third-Party APIs (e.g., Payment Gateway, Social Media)
    • Type: Software System
    • Description: External APIs that the project interacts with.
    • Responsibilities: Provides specific functionalities (e.g., payment processing, social login).
    • Security controls: API keys, OAuth2, secure communication (HTTPS).

  • Element:

    • Name: Email Server (e.g., SMTP)
    • Type: Software System
    • Description: The server used for sending emails.
    • Responsibilities: Sends transactional emails, notifications, etc.
    • Security controls: Secure SMTP configuration, TLS encryption.

  • Element:

    • Name: Administrator
    • Type: Person
    • Description: A user with administrative privileges.
    • Responsibilities: Manages the application, configures settings, monitors performance.
    • Security controls: Strong authentication, access controls.

C4 CONTAINER

graph LR
    User["User (Web Browser/Mobile App)"] -- "HTTPS" --> WebServer["Web Server (e.g., Nginx, Apache)"]
    WebServer -- "WSGI" --> DjangoApp["Django Application (DRF)"]
    DjangoApp -- "ORM" --> Database["Database (e.g., PostgreSQL, MySQL)"]
    DjangoApp -- "HTTP/HTTPS" --> ThirdPartyAPIs["Third-Party APIs"]
    DjangoApp -- "SMTP" --> EmailServer["Email Server"]
    Admin["Administrator"] -- "HTTPS" --> WebServer
Loading

Element Descriptions:

  • Element:

    • Name: User (Web Browser/Mobile App)
    • Type: Person
    • Description: A user interacting with the API.
    • Responsibilities: Initiates requests, views responses.
    • Security controls: Uses HTTPS.

  • Element:

    • Name: Web Server (e.g., Nginx, Apache)
    • Type: Container: Web Server
    • Description: The web server that handles incoming requests.
    • Responsibilities: Serves static content, reverse proxies requests to the Django application.
    • Security controls: HTTPS configuration, request filtering, rate limiting.

  • Element:

    • Name: Django Application (DRF)
    • Type: Container: Python/Django
    • Description: The core application built using Django and DRF.
    • Responsibilities: Handles API logic, interacts with the database and other services.
    • Security controls: Authentication, authorization, throttling, input validation, output encoding.

  • Element:

    • Name: Database (e.g., PostgreSQL, MySQL)
    • Type: Container: Database
    • Description: The database server.
    • Responsibilities: Stores and retrieves data.
    • Security controls: Database access controls, encryption at rest, regular backups.

  • Element:

    • Name: Third-Party APIs
    • Type: Software System
    • Description: External APIs.
    • Responsibilities: Provides specific functionalities.
    • Security controls: API keys, OAuth2, secure communication (HTTPS).

  • Element:

    • Name: Email Server
    • Type: Software System
    • Description: The server for sending emails.
    • Responsibilities: Sends emails.
    • Security controls: Secure SMTP configuration, TLS encryption.

  • Element:

    • Name: Administrator
    • Type: Person
    • Description: A user with administrative privileges.
    • Responsibilities: Manages the application.
    • Security controls: Strong authentication, access controls.

DEPLOYMENT

Possible Deployment Solutions:

  1. Traditional Server Deployment (e.g., using a VPS with Nginx/Apache and Gunicorn/uWSGI).
  2. Containerized Deployment (e.g., using Docker and Docker Compose, or Kubernetes).
  3. Platform-as-a-Service (PaaS) Deployment (e.g., using Heroku, AWS Elastic Beanstalk, Google App Engine).
  4. Serverless Deployment (e.g., using AWS Lambda, Azure Functions, Google Cloud Functions).

Chosen Solution (for detailed description): Containerized Deployment using Docker and Docker Compose.

graph LR
    Internet["Internet"] -- "HTTPS" --> LoadBalancer["Load Balancer (e.g., Nginx, HAProxy)"]
    LoadBalancer -- "HTTPS" --> WebServerNode1["Web Server Node 1 (Docker Host)"]
    LoadBalancer -- "HTTPS" --> WebServerNode2["Web Server Node 2 (Docker Host)"]
    WebServerNode1 -- "Docker Network" --> AppContainer1["App Container (Django/DRF)"]
    WebServerNode2 -- "Docker Network" --> AppContainer2["App Container (Django/DRF)"]
    AppContainer1 -- "Docker Network" --> DBContainer["Database Container (e.g., PostgreSQL)"]
    AppContainer2 -- "Docker Network" --> DBContainer
Loading

Element Descriptions:

  • Element:

    • Name: Internet
    • Type: External
    • Description: The public internet.
    • Responsibilities: Source of incoming requests.
    • Security controls: N/A

  • Element:

    • Name: Load Balancer (e.g., Nginx, HAProxy)
    • Type: Infrastructure Node
    • Description: Distributes incoming traffic across multiple web server nodes.
    • Responsibilities: Load balancing, SSL termination.
    • Security controls: HTTPS configuration, DDoS protection.

  • Element:

    • Name: Web Server Node 1 (Docker Host)
    • Type: Infrastructure Node
    • Description: A server hosting Docker containers.
    • Responsibilities: Runs the web server and application containers.
    • Security controls: Firewall, SSH access control, regular security updates.

  • Element:

    • Name: Web Server Node 2 (Docker Host)
    • Type: Infrastructure Node
    • Description: A server hosting Docker containers.
    • Responsibilities: Runs the web server and application containers.
    • Security controls: Firewall, SSH access control, regular security updates.

  • Element:

    • Name: App Container 1 (Django/DRF)
    • Type: Container Instance
    • Description: A Docker container running the Django/DRF application.
    • Responsibilities: Handles API requests.
    • Security controls: Inherits security controls from the Django/DRF application.

  • Element:

    • Name: App Container 2 (Django/DRF)
    • Type: Container Instance
    • Description: A Docker container running the Django/DRF application.
    • Responsibilities: Handles API requests.
    • Security controls: Inherits security controls from the Django/DRF application.

  • Element:

    • Name: DB Container (e.g., PostgreSQL)
    • Type: Container Instance
    • Description: A Docker container running the database server.
    • Responsibilities: Stores and retrieves data.
    • Security controls: Database access controls, encryption at rest, regular backups.

BUILD

graph LR
    Developer["Developer"] -- "Git Push" --> GitRepository["Git Repository (e.g., GitHub)"]
    GitRepository -- "Webhook Trigger" --> CIEnvironment["CI Environment (e.g., GitHub Actions)"]
    CIEnvironment -- "Run Tests" --> TestSuite["Test Suite (Unit, Integration, etc.)"]
    CIEnvironment -- "Run SAST" --> SASTScanner["SAST Scanner (e.g., Bandit, SonarQube)"]
    CIEnvironment -- "Run SCA" --> SCAScanner["SCA Scanner (e.g., Snyk, Dependabot)"]
    CIEnvironment -- "Build Docker Image" --> DockerImage["Docker Image"]
    DockerImage -- "Push to Registry" --> ContainerRegistry["Container Registry (e.g., Docker Hub, ECR)"]
Loading

Build Process Description:

  1. Developer commits and pushes code changes to a Git repository (e.g., GitHub).
  2. A webhook triggers the CI/CD pipeline in a CI environment (e.g., GitHub Actions, Jenkins).
  3. The CI environment runs a series of steps:
    • Runs the test suite (unit tests, integration tests, etc.).
    • Performs Static Application Security Testing (SAST) using a tool like Bandit or SonarQube.
    • Performs Software Composition Analysis (SCA) using a tool like Snyk or Dependabot to identify vulnerabilities in dependencies.
    • Builds a Docker image containing the application code and its dependencies.
    • Pushes the Docker image to a container registry (e.g., Docker Hub, Amazon ECR).

Security Controls in Build Process:

  • Git Repository: Access controls, branch protection rules.
  • CI Environment: Secure configuration, limited access, audit logging.
  • Test Suite: Ensures code quality and helps prevent regressions.
  • SAST Scanner: Identifies potential security vulnerabilities in the application code.
  • SCA Scanner: Identifies vulnerabilities in third-party dependencies.
  • Container Registry: Access controls, image signing, vulnerability scanning.

RISK ASSESSMENT

Critical Business Processes:

  • API request handling and processing.
  • Data storage and retrieval.
  • User authentication and authorization.
  • Integration with third-party services.

Data to Protect and Sensitivity:

  • User data (e.g., usernames, passwords, email addresses, personal information): High sensitivity.
  • API keys and secrets: High sensitivity.
  • Application data (depending on the specific application): Variable sensitivity, ranging from low to high.
  • Transaction data (if applicable): High sensitivity.
  • Session data: Medium sensitivity.

QUESTIONS & ASSUMPTIONS

Questions:

  • Are there any specific compliance requirements (e.g., GDPR, HIPAA, PCI DSS) that the project needs to adhere to?
  • What is the expected scale of the API (number of users, requests per second)?
  • What are the specific third-party APIs that the project will integrate with?
  • What is the current process for handling security vulnerabilities reported by the community or discovered internally?
  • What level of logging and monitoring is currently in place?

Assumptions:

  • BUSINESS POSTURE: The project aims to be a general-purpose API framework and does not target any specific industry or compliance regime by default.
  • SECURITY POSTURE: Developers using the framework are responsible for implementing appropriate security measures in their applications. The framework provides the tools, but secure configuration is the responsibility of the user.
  • DESIGN: The deployment architecture can vary significantly depending on the specific needs of the project using DRF. The containerized deployment described above is a common and recommended approach, but other options are possible. The build process assumes a modern CI/CD pipeline with automated security checks, but this may not be the case for all projects using DRF.