CrypTool Book

Chapter 14: CUDA Tutorial – Cryptanalysis of Classical Ciphers Using Modern GPUs and CUDA, April 2021

This 90-page chapter covers a practical introduction how to write CUDA programs on Linux and Windows. It explains what are the concepts, how to overcome problems (threads, shared memory, debugging) and how to deal with trade-offs. The theory is accompanied with practical examples, and two complete stand-alone GPU tools for automatically decrypting ciphertexts (ciphertext-only attack) are implemented. These tools target ciphertexts encrypted by monoalphabetic substitution (MAS) or by single-columnar transposition ciphers.

The additional appendices will be published here soon. They contain e.g. a list of movies and novels where cryptography plays a role. The appendices also offer a quick overview about the cryptographic functions delivered by the different CrypTool variants.

For many algorithms there are small and executable code samples in Python, SageMath, OpenSSL, or they are further explained with one of the CrypTool variants. You can download the SageMath scripts here. You can download the OpenSSL scripts here.

SageTeX and PythonTeX were used to create the CrypTool book. SageTeX is briefly described in the CTB appendix about SageMath. For PythonTeX we have described our experiences with many examples in the document PythonTex-by-Examples.pdf (about 60 pages). Both tools can be used to nicely automate calculations in LaTeX documents.

General News

See all posts
CrypTool 2 Release 2023.1 published

In June 2023, we released version "2023.1" which is the first release of the year. The previous CT2 versi...

Read more ... 06/16/23
More than 50 undeciphered letters of Mary Stuart were found and deciphered by George Lasry, Norbert Biermann and Satoshi Tomokiyo

For Mary Stuart researchers, it's probably the biggest cryptography discovery in recent years. Our colleagu...

Read more ... 02/07/23
CrypTool 2 Release 2022.2 released

In December 2022 we released "CrypTool 2 – 2022.1", the first release this year. The last CrypTool 2 release before...

Read more ... 12/24/22