Click here to Skip to main content

Article

RSA Encryption Elgorithm

immaad

Rate me:

1.24/5 (25 votes)

11 Oct 2004

69.6K

4K

20

5

This code implements RSA encryption technique in an efficient and reusable way.

Download source and demo files - 56 Kb

Introduction

Famous encryption algorithms have been a mystery for developers who use them by just getting the implementation from somewhere else.

This implementation of RSA is to understand it and to use it in an easy and customizeable way.

The encryption is based on the formula C = M^e (mod n) where n=p*q and p,q,e are prime numbers.

Descryption is perform with the formula M = C^d (mod n) and d can be calculate using ed = 1 (mod (p-1)(q-1)).

Try implementing RSA yourself, its a real fun :) I love to program mathematics!!!

You will see my other algorithms very soon.

License

This article has no explicit license attached to it but may contain usage terms in the article text or the download files themselves. If in doubt please contact the author via the discussion board below.

A list of licenses authors might use can be found here

Written By

immaad

Software Developer

Australia

C/C++, C# .NET, VB.NET, Linux, Oracle, PostgreSQL, MYSQL

Comments and Discussions

I'm astonished by the pointlessness of postings on here.

I'd like to take the time to point out that this is a programming website. Although you've done a nice job of noting there is such a thing as the RSA algorithm, you've not explained anything about it.

Could you tell me how this is better than the ~126,000 results I get if I search for RSA Encryption Algorithm on Google? Do you even know why RSA works, what its costs and benefits are?

I'd now like to take a moment to go through the article.

---
"Famous encryption algorithms have been a mystery for developers who use them by just getting the implementation from somewhere else."

Well, if you're a developer and you're blindly plugging algorithms in you shouldn't be developing. Particularly with regards to Cryptography where the absolute biggest problem with (cryptographically) weak software is in their eventual implementation. I trust some people to implement things properly, but I'd always want to dig around and understand its implications first.

This of course ignores the fact that if they're famous they're unlikely to be a mystery, but I'll put that down to the fact that English is unlikely to be your first language.

"This implementation of RSA is to understand it and to use it in an easy and customizeable way"

I have to say I've not looked through all of your code. However, from what I have seen it requires someone to understand how to generate each of the primary numbers (and most importantly which ones are public/private) -- something also ignored in the article itself. The main reason to use RSA is that its asymmetric and you can therefore publish certain values to enable people to communicate securely with you. However, how would someone without knowledge of RSA know which parts you can (and can't) publish.

To be quite brutally honest, I don't know how the article has a rating of 1.71. At least it has source code I suppose.

Anyway, if you do want to contribute something to CodeProject (and I would emplore you to do so), please, please, please make it worth reading. This site (is both fortunately and unfortunately) getting an incredible amount of traffic but this is increasing the amount of cruft that seems to be appearing.

Why not take the opportunity to explain the history of RSA, it's chief uses, and most importantly, how developers can apply it to their work -- and show us how. I like it when articles spark an idea in me that I can then work into something I'm working on, this article just inspired this response.

--
Paul
"Put the key of despair into the lock of apathy. Turn the knob of mediocrity slowly and open the gates of despondency - welcome to a day in the average office."
- David Brent, from "The Office"

MS Messenger: paul@oobaloo.co.uk
Download my PGP public key

General News Suggestion Question Bug Answer Joke Praise Rant Admin

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.

Go to top