EncryptedMessenger

Structure

EncryptedMessenger consists of two parts:

1. MessengerClient: Command line interface for logging into accounts, sending and receiving messages.
2. MessengerServer: Server that can be run using Apache Tomcat and MySQL. The server is used for exchanging messages and keys.

Goals of Project

Originally, I merely wanted to take a take a look at the Java cryptography libraries. Once I had done this, I sent encrypted messages from port to port on localhost.
The project rapidly grew into something bigger than intended. In the end I had a messenger server running on a Raspberry Pi that allowed messenger clients to communicate.

Technological Aspects Covered

• Security (in Java):
  • RSA encryption
  • Password-based encryption
  • KeyStore
• MySQL (accessed using JDBC)
• Apache Tomcat

Dependencies

• Gson (https://github.com/google/gson)
• Bouncy Castle (https://www.bouncycastle.org/)

Establish connection to MySQL server in Java using JDBC:
https://www.javatpoint.com/example-to-connect-to-the-mysql-database

Future Work

I worked on this project during Winter break. Once the semester started, I stopped working. Thus, there are some aspects that are still undesirable:

• GUI version using JavaFX was never completed.
• Messages are encrypted using asymmetric encryption (RSA) which is slow. Ideally, EncryptedMessenger should use symmetric encryption instead. RSA could still be used as a means of exchanging keys or authentication.
• Currently, the messages cannot exceed a certain length due to the RSA message length limit.
• Add salt to the hashed passwords on the server.