Tag Archives: Cryptography

How to get a job with 250 lines of code

Recently, I stumbled upon a cryptographic challenge posed by a company called “Trustpilot”. The problem was available at http://followthewhiterabbit.trustpilot.com/challenge2.html. For completeness I post a screenshot here: Let that sink for a little while. Generously, the key has only six unknowns, … Continue reading

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The RC4 stream cipher

Today I will continue my crypto-101 series with the very popular stream cipher RC4 (Ron’s code 4 by Ronald L. Rivest). I want to say at the very beginning that RC4 is not regarded as secure anymore as by today’s … Continue reading

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A hash function primer I: SHA-1

Today I am starting a new series on hash algorithms, beginning with SHA-1. The goal is to review the algorithm and watch a data example being digested. It can be used as a reference and to test your own implementations … Continue reading

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