Tools for Analyzing DES and TDES Rukman Senanayake

Tools for Analyzing DES and TDES Rukman Senanayake rukman@sri. com

Overview Reasons for analyzing DES n DES/TDES algorithm visualization n Brief introduction of the tools n Demo n

Why do we need to analyze DES? Modern Cryptography and DES n Publication of the DES algorithm and its influence n The NSA ‘tweaks’ and the outcry (reduction of the key length) n Understand the ‘tweaks’ -> Analyze DES in depth n

Why do we need to analyze DES? n Bruce Schneier, one of the foremost security experts in the world, in his 2004 article (published by ZD. net) regarding DES’ thirty year reign points out the following interesting facts: “It's not an exaggeration to say that the publication of DES created the modern academic discipline of cryptography. The first academic cryptographers began their careers by trying to break DES, or at least trying to understand the NSA’s tweak. And almost all of the encryption algorithms -- public-key cryptography, in particular -- can trace their roots back to DES. Papers analyzing different aspects of DES are still being published today”.

DES/TDES Algorithms n Skip

The Tools… n n n n Customizable S-Boxes GUI with all intermediate results Text report of the settings and encryption process Parallel execution of encryption (for comparison) TDES : Graphical overview of the algorithm DES : All the steps (initial permutation, pbox permutation, etc) are implemented These tools are SLOW (written in Java)

DES Algorithm Visualization

TDES Algorithm Visualization

TDES Algorithm Visualization

Demo