Implementing RSA using VC6

• Implementing RSA using VC6

  Introduction

  To test our understanding in RSA public key cryptosystem, we were being asked to develop a computer program to demonstrate the cryptosystem. The whole system consists of a random number generator, an encoding module that is able to encode characters into numbers, an encryption module as well as decryption module and finally an RSA cryptosystem cracking module.

  Technical Information

  Programming Language

  The program is written in Microsoft^® Visual C6, the reason why Visual C6 is being selected is because we wanted to do something simple. There is no GUI being implemented as we wanted to spend more time in enhancing the program.

  Random Number Generator

  To generate random number, we used Blum-Blum-Shub random number generator as we found it to be the easiest to implement.

  Modular Exponential Problem

  I happened to find a general solution suggestion on a Wikipedia entry when I was browsing the internet around to find a solution to modular exponential problem. The code snippet posted on the wikipedia entry claimed that it came from …

  RSA

  RSA is a cryptosystem …

  Prime Number Testing

  Large Number Factorization

  Brief Documentation with Screenshots

  Implementing RSA with Visual C

  Credits

  • Developed by Me and Regina as well as Janet and Janice (No working copy from them).

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