Need

Implementation of proper authorization controls for web services

Context

• Usage of Python 3 for developing applications and scripts
• Usage of Django for building web applications

Description

Non compliant code

        from django.http import HttpResponse
from django.views import View

class MyView(View):
    def get(self, request, *args, **kwargs):
        return HttpResponse('Hello, World!')
        
        

In the above code, we've defined a simple Django view named MyView which responds to HTTP GET requests. The get method takes a request argument along with any other arguments and keyword arguments, and returns a HttpResponse saying 'Hello, World!'.

This code is vulnerable to improper authorization control because it doesn't have any mechanism to check if the incoming request is authorized to access the resource it's requesting for. Any request, regardless of where it's coming from or who it's made by, will be able to access this view and receive a 'Hello, World!' message in response. This could potentially expose sensitive data or system functionality to unauthorized users, posing a significant security risk.

Steps

• Implement an authentication mechanism for the web service. This could be token-based, session-based, or any other method that suits your application.
• Once the authentication mechanism is in place, implement an authorization control mechanism. This could be role-based access control (RBAC), access control lists (ACLs), or any other method that suits your application.
• Ensure that every request to the web service is checked against this authorization control mechanism to determine if the requester has the necessary permissions to perform the requested action.
• Regularly update and review the authorization control mechanism to ensure it cannot be bypassed.
• Consider using a framework or library that provides built-in mechanisms for authentication and authorization to reduce the chance of errors.

Compliant code

        from django.http import HttpResponse
from django.contrib.auth.decorators import login_required
from django.views import View

class MyView(View):
    @login_required
    def get(self, request, *args, **kwargs):
        return HttpResponse('Hello, World!')
        
        

The updated code now includes an authentication mechanism using Django's built-in login_required decorator. This decorator ensures that only authenticated users can access the view. If a user is not authenticated, they will be redirected to the login page.

The login_required decorator is a simple and effective way to add authentication to Django views. However, it only provides authentication, not authorization. If you need to control access to views based on user roles or permissions, you will need to implement an additional authorization control mechanism.

For example, you could use Django's built-in permissions and groups system to implement role-based access control (RBAC). You could assign permissions to different groups of users, and then check if a user has the necessary permissions before allowing them to access a view.

Remember to regularly review and update your authentication and authorization mechanisms to ensure they cannot be bypassed. Consider using a security-focused development framework or library that provides built-in mechanisms for authentication and authorization to reduce the chance of errors.

References

• 039. Improper authorization control for web services