Secure Message Exchange Protocol with Microagents

Table of Contents

1. Introduction
2. Setting up the Code
3. Importing Necessary Classes
4. Defining the Message Format
5. Creating Agents
6. Defining Agent Behaviors
7. Running the Script
8. Conclusion

Introduction

In this Tutorial, we will learn how to set up the code for a protocol that allows for the exchange of messages between two microagents. The purpose of this protocol is to ensure authenticity and prevent tampering of messages exchanged between these microagents. We will walk through the steps required to create the necessary script and demonstrate the functionality of the protocol.

Setting up the Code

To get started, we need to create a script named "message_verification.py" for this task. Open the text editor application and start writing the code to implement the protocol.

Importing Necessary Classes

To begin, we need to import several classes that will be used in our code. These classes include:

• hashlib: a Python built-in module that provides secure hash algorithms.
• Agent: a class provided by the microagents library, responsible for sending and receiving messages.
• Bureau: a class provided by the microagents library, representing a collection of agents and managing their communication.
• Context: another class provided by the microagents library, providing a context for message exchange.
• Model: an additional class provided by the microagents library for defining message formats.
• Identity: a class provided by the microagents.crypt module, offering methods for generating and verifying digital signatures.

Defining the Message Format

We now need to define the message format using the Message class, or as a subclass of the Model class. The message format consists of three attributes: message, digest, and signature.

• message: a STRING representing the message text.
• digest: a string representing the SHA-256 hash of the message.
• signature: a string representing the digital signature of the hash using the sender's private key.

Creating Agents

Next, we proceed by creating two agents named Alice and Bob using the Agent class. Each agent is given a unique name and a seed password used to generate their cryptographic key pair.

Defining Agent Behaviors

Now, we define the behaviors of our agents. We start by defining a function named send_message which will be periodically called to send messages from Bob to Alice. The function takes a single argument, CTX, which represents the context object containing data and functions related to the agent. Within this function, we create a message and compute its digest using the encode function. The message is then sent to Alice along with the digest and the signature of the digest using the CTX.send function and Alice's private key's sign_digest function, respectively.

We also define a function named receive_message which is used to receive and process messages. This function takes three arguments: CTX, sender, and message. It verifies the authenticity of the message using the Identity.verify_digest function.

• If the message cannot be verified, an assertion error is raised.
• If the message is verified, the function logs that the message was verified and displays the content of the message.

We then define the behavior of Bob's agent using the function Bob.receive_message, which is used to receive and process messages sent from Alice. Similarly, the authenticity of the message is verified, and if successful, a response message is created, and its digest is computed using the encode function. The response message is then sent back to Alice using the CTX.send function.

Finally, we add both agents to the Bureau object to run them together.

Running the Script

We are now ready to run our script. Make sure to save your script in your text editor application and go back to your terminal. Activate your virtual environment and run the script.

As observed from the output, Alice sends a message to Bob, which is successfully verified and its content is displayed. Bob then responds with a message, which is also successfully verified, and its content is displayed.

Conclusion

In this tutorial, we have learned how to set up the code for a protocol that allows microagents to exchange messages while ensuring authenticity and preventing tampering. By following the steps outlined in this tutorial, you can create your own scripts and implement secure message exchange protocols using microagents.

Note: Please note that the examples provided in this tutorial are for demonstrative purposes only and may need to be adapted for your specific requirements.