Screenshot of the RSA calculator, showing the fields that you can fill into and the results as they propagate through the calculation

Lift The Veil On RSA With This RSA Calculator

July 8, 2022 by Arya Voronova 2 Comments

Encryption algorithms can be intimidating to approach, what’s with all the math involved. However, once you start digging into them, you can break the math apart into smaller steps, and get a feel of what goes into encryption being the modern-day magic we take for granted. Today, [Henry Schmale] writes to us about his small contribution to making cryptography easier to understand – lifting the veil on the RSA asymmetric encryption technique through an RSA calculator.

With [Henry]’s calculator, you can only encrypt and decrypt a single integer, but you’re able to view each individual step of an RSA calculation as you do so. If you want to understand what makes RSA and other similar algorithms tick, this site is an excellent starting point. Now, this is not something you should use when roll your crypto implementations – as cryptographers say in unison, writing your own crypto from scratch is extremely inadvisable. [Henry] does say that this calculator could be useful for CTF players, for instance, but it’s also undeniably an accessible learning tool for any hacker out there wishing to understand what goes on under the wraps of the libraries we use.

In modern day, cryptography is instrumental to protecting our freedoms, and it’s a joy to see people work towards explaining the algorithms used. The cryptography tools we use day-to-day are also highly valuable targets for governments and intelligence agencies, willing to go to great lengths to subvert our communication security – so it’s even more important that we get acquianted with the tools that protect us. After all, it only takes a piece of paper to encrypt your communications with someone.

Netscape Communicator And SHA-1 Written Into Brexit Agreement

December 28, 2020 by Jenny List 36 Comments

We pity the civil servants involved in the negotiations between the European Union and the United Kingdom, because after tense meetings until almost the Eleventh Hour, they’ve had to cobble together the text of a post-Brexit trade agreement in next-to-no time. In the usual manner of such international agreements both sides are claiming some kind of victory over fish, but the really interesting parts of the document lie in the small print. In particular it was left to eagle-eyed security researchers to spot that Netscape Communicator 4, SHA-1, and RSA encryption with a 1024-bit key length are recommended to secure the transfer of DNA data between states. The paragraphs in question can be found on page 932 of the 1256-page agreement.

It’s likely that some readers under 30 years old will never have used a Netscape product even though they will be familiar with Firefox, the descendant Mozilla software. Netscape were a pioneer of early web browsers, and Communicator 4 was the company’s all-in-one browser and email offering from the late 1990s. It and its successors steadily lost ground against Microsoft’s Internet Explorer, and ultimately faded away along with the company under AOL ownership in the late 2000s. Meanwhile the SHA-1 hashing algorithm has been demonstrated to be vulnerable to collision attacks, and computing power has advanced such that 1024-bit RSA encryption can be broken in a sensible time frame by anyone with sufficient GPU power to give it a try. It’s clear that something is amiss in the drafting of this treaty, and we’d go so far as to venture the opinion that a tired civil servant simply cut-and-pasted from a late-1990s security document.

So will the lawmakers of Europe now have to dig for ancient software as mandated by treaty? We hope not, as from our reading they are given as examples rather than as directives. We worry however that their agencies might turn out to be as clueless on digital security as evidently the civil servants are, so maybe Verizon Communications, current owners of the Netscape brand, could be in for a few support calls.