I’ve (re)started the Cryptopals Crypto Challenges too many times to remember. I think I’ve implemented a Vigenère solution from scratch enough times, and I need a new technical challenge that I can periodically jump into with enthusiasm and then procrastinate into memory oblivion.
Enter, Hack The Box.
The first challenge…
I recently got an invitation to watch a debate between the UMBC philosophy and computer science departments regarding the ethics of brain-computer interfaces.
BCIs are those interfaces that seek to bypass human motor and sensory systems through direct connectivity to the central nervous system. The field is nascent, but it’s…
I’ve been messing around with some basic cryptography challenges ever since DEFCON, which was a ton of fun and very informative. The most recent challenge involved breaking a Vigenere cipher (also known as a repeating key XOR).
Here’s the basic algorithm:
1. Calculate normalized Hamming distances for various key sizes, and take the smallest one.
2. Chunk cipher text into key-sized chunks.
3. Transpose the chunk bytes.
4. Find the single-byte XOR key for each transposed chunk with frequency analysis.
5. Concatenate the keys, and find your plain text.
6. ???
7. Profit!
Fun stuff! So satisfying to see the plain text at the end of a challenge.
In nearly every one of my graduate reading seminars, at some point, we were asked to read Professor Elke Duncker’s 2002 Joint Conference on Digital Libraries (JCDL) presentation, “Cross-cultural usability of the library metaphor”. …
I weigh about 155 lbs. If you convert that to metric units, it’s about 70,306 grams, which is about as many paperclips.
The average human body is mostly water, about 80-some percent. There’s other stuff in there too, though. In fact, the rough breakdown by weight is about 65% Oxygen…
