[Paper Review] Unidirectional Secure Information Transfer via RabbitMQ

Marcel Maatkamp|arXiv (Cornell University)|Jan 1, 2015

Big Data Technologies and Applications3 citations

TL;DR

This paper proposes a cost-effective, open-source solution for unidirectional secure information transfer using RabbitMQ over data diodes, enabling transparent mirroring of message bus traffic with end-to-end encryption. The approach successfully demonstrates bidirectional-like data flow security through asymmetric key encryption and message queuing, proving feasible for transferring sensitive data—including evidence-admissible information—across air-gapped networks.

ABSTRACT

Protecting computer systems handling possible sensitive information is of the utmost importance. Those systems are typically air-gapped with data diodes to assure that no information can physically flow back. Traditional computer protocols like HTTP or SOAP which are normally used to transport information between computers are typical bi-directional communication protocols and are thus unsuitable to be used over a data diode. Currently the only commercially available protocols over a data diode sold by vendors are file-based protocols. Other protocols can be custom made but are expensive and proprietary. There are currently no open source solutions to stream data in a generic way over a data diode other than those file-based solutions. Purpose of the dissertation is to research if open source technology can be used to mirror the contents of a messagebus over a data diode to get a cost effective security-proof and almost maintenance-free solution. and to further research if this technology can be used to transfer not only plain text data but also data sensitive by nature by using end-to-end encryption so that this information could even be admitted as evidence. Method used to validate the research is a practical case study that shows how a sensor stream can send unencrypted and encrypted events over a data diode of arbitrary size via a message bus which are transparently and securely transferred and re-emitted internally without any kind of configuration management. Results show that it is indeed possible to successfully mirror data from a Message Bus over a data diode and it is thus worthwhile to further invest in this technology.

Motivation & Objective

• To evaluate whether open-source messaging technology like RabbitMQ can enable secure, cost-effective, and maintenance-free unidirectional data transfer across air-gapped networks.
• To investigate if end-to-end encryption can be applied to message bus data over data diodes without compromising the unidirectional security model.
• To determine if such a system can handle not only plain text but also sensitive, evidence-grade data in a forensically sound manner.
• To develop and validate a practical, transparent, and scalable solution for transferring real-time sensor data across data diodes using open standards.

Proposed method

• Implementation of a dual-network architecture using RabbitMQ as a message broker in both 'black' (untrusted) and 'red' (trusted) zones, connected via a data diode.
• Use of AMQP protocol to enable interoperability and message queuing between RabbitMQ instances on opposite sides of the data diode.
• Adoption of asymmetric key encryption (RSA) to secure message payloads, with encrypted keys and data transmitted via the message bus.
• Design of a secure message wrapper class (SecureMessage) to encapsulate encrypted data, initialization vectors (IV), and digital signatures for integrity.
• Use of Docker containers to isolate and deploy RabbitMQ and Node-RED environments for testing, ensuring configuration transparency and reproducibility.
• Implementation of a sensor simulation system that generates temperature events, which are encrypted and transmitted across the data diode in real time.

Experimental results

Research questions

• RQ1 Can RabbitMQ be used to mirror message bus traffic across a data diode in a secure, transparent, and unidirectional manner?
• RQ2 Is end-to-end encryption feasible and effective when applied to message bus data over a data diode without breaking the unidirectional flow?
• RQ3 Can the system reliably transfer sensitive, evidence-grade data across air-gapped networks while preserving data integrity and authenticity?
• RQ4 Does the use of open-source tools like RabbitMQ and Docker provide a scalable, low-maintenance, and cost-effective alternative to proprietary solutions?

Key findings

• The system successfully mirrored message bus traffic from a 'black' network to a 'red' network across a data diode using RabbitMQ, demonstrating transparent data flow.
• End-to-end encryption was implemented effectively using RSA, with encrypted data, keys, and digital signatures transmitted securely across the diode.
• The solution maintained the unidirectional property of the data diode, ensuring no reverse data flow, even with complex message structures.
• The use of Dockerized RabbitMQ and Node-RED enabled configuration-free, reliable, and scalable deployment with minimal maintenance.
• Encrypted messages were correctly decrypted and re-emitted in the internal network, preserving message integrity and authenticity as verified by digital signatures.
• The approach proved viable for transferring sensitive data, including forensic evidence, due to strong cryptographic controls and end-to-end verification.