Cedar: A New Language for Expressive, Fast, Safe, and Analyzable Authorization

Core Concepts

Cedar is a new authorization policy language designed to be ergonomic, fast, safe, and analyzable. The authors advocate for externalizing access control rules into policies written in Cedar to improve readability, auditability, and maintainability of authorization logic.

Abstract

Cedar introduces a novel approach to authorization by externalizing access control rules into policies written in a domain-specific language. The language balances expressiveness, performance, safety, and analyzability. Cedar's design ensures precise policy analysis and efficient policy evaluation. Key points include: Cedar's design aims to balance four competing goals: expressiveness, performance, safety, and analyzability. Policies as code approach allows developers to write authorization logic separately from application code. Cedar's symbolic compiler reduces policies to SMT formulas for automatic proof of access invariants. Validation against schemas ensures error-free policies before deployment.

Stats

Cedar performs 28.7×-35.2× faster than OpenFGA and 42.8×-80.8× faster than Rego. Policy slicing in Cedar makes authorization 10.0×-18.0× faster on average.

Quotes

"Rather than embed authorization logic in an application’s code, developers can write that logic as Cedar policies." "Cedar’s simple syntax supports common authorization use-cases with readable policies." "Cedar has equally or more readable policies compared to other languages."

Key Insights Distilled From

Cedar

by Joseph Cutle... at arxiv.org 03-08-2024

https://arxiv.org/pdf/2403.04651.pdf

Deeper Inquiries

How does the adoption of Cedar impact the development process of cloud-based applications

The adoption of Cedar can significantly impact the development process of cloud-based applications. By externalizing access control rules into separate policies written in Cedar, developers can streamline the authorization logic implementation within their applications. This separation allows for easier management and maintenance of access control rules, as they are no longer intertwined with application code. Developers can write policies in a more intuitive and readable manner using Cedar's syntax, which supports common authorization use-cases based on roles, attributes, and relationships. Furthermore, Cedar's policy validator helps prevent errors by ensuring that policies align with the specified schema. This validation process enhances the robustness of the authorization logic and reduces the likelihood of runtime issues related to access control. Overall, adopting Cedar simplifies the implementation of authorization logic in cloud-based applications, making it more efficient and manageable for developers.

What potential challenges could arise from externalizing access control rules into separate policies

Externalizing access control rules into separate policies using a language like Cedar comes with its own set of challenges. One potential challenge is ensuring consistency across all policies to maintain coherent access control throughout the application. As policies are decentralized from application code, it becomes crucial to manage versioning effectively to track changes accurately and avoid conflicts between different versions of policies. Another challenge is maintaining security when dealing with sensitive data or critical operations. Externalized policies must be carefully reviewed to prevent vulnerabilities or loopholes that could compromise system security. Additionally, managing a large number of complex policies can become cumbersome without proper documentation and organization practices in place. Moreover, integrating externalized policy evaluation mechanisms seamlessly into existing systems may pose technical challenges during implementation. Ensuring compatibility with other components and services within a cloud-based application requires thorough testing and integration efforts. In summary, while externalizing access control rules offers benefits such as improved readability and maintainability, addressing challenges related to consistency, security considerations, scalability, and integration complexities is essential for successful policy management.

How might the principles behind Cedar be applied to other domains beyond technology

The principles behind Cedar can be applied beyond technology domains to various fields where complex rule-based decision-making processes are involved. For instance: Legal Compliance: Legal frameworks often require adherence to specific regulations governing permissions or restrictions on certain actions or data usage. By utilizing a structured policy language similar to Cedar's design principles, organizations can ensure compliance through clear articulation of legal requirements. Healthcare: In healthcare settings where patient privacy and data security are paramount concerns, adopting an expressive yet analyzable policy language like Cedar could help define precise access controls for medical records, ensuring only authorized personnel have appropriate levels of information access. Financial Services: The financial sector deals with stringent regulatory requirements regarding data protection and transaction authorizations. Implementing a robust policy language akin to Cedar would enable financial institutions to enforce secure protocols for user authentication, transaction approvals,and fraud detection. By applying concepts from Cedar-like languages outside traditional technology realms, organizations across various industries can enhance governance structures,promote transparency,and mitigate risks associated with decision-making processes involving complex rule sets