hacker.org

Very satisfying to solve this bastard with netcat. Netcat shits on telnet. I'd done others with plugins, but that doesn't teach anything.

Took me ages though, because I was using http 1.0 in my header line, Worked once I switched to 1.1.

I got way too distracted by semaphore, trying to find a semaphore code that they corresponded to. One nice fruit of that search was this little gem:

When I first started these challenges, I was on windows. Now, I'm on linux.

Strings for the win.

Heheh, I took a low-tech approach: I copied the html source to a document, find and replace with R,L,U,D as appropriate. After trying blocking it out in excel I had a better idea: if the challenge is about an etch-a-sketch, why not use one? Googled for an online version and voila: http://www.ohioart...

Ahhh, snap... that was satisfying to solve. Very nice one adum, once again I learned a bunch. Using letters to represent bits for each byte: aaaaaaaabbbbbbbbcccccccc, I spent ages trying to solve for c. As pepe suggests, that's the wrong byte's bits to go for. Makes it simple to restrict keys tested...

Oh man, this one is kicking my ass... I've loved the crypto challenges on this branch so far, no problems there, but I just can't figure out a sensible way to solve for the key without silly brute force (I'd love to understand rather than do that). Are any solvers still around who I can PM with my u...

Man, while the principals are the same as the prior cypher, I hadn't fully understood the endianness problems that arose... the tolerance for interference from overflows was large enough that I could approximate the answer. In number 3 the multiplication factor just baloons out the overflow, so you ...

I should not do these late at night with scotch... I'm learning c++ by solving these challenges, and had particular difficulty getting an alphabet 'wrap around' with modulo calculations (which I learned from the text to the feedback cyphers - loved that when I saw how it worked). I got the answer, b...

Hmm... I don't see a c++ code, so I'll throw mine up... but man it takes a lot more structure than the python or ruby examples I see here: #include <iostream> #include <string> #include <ctype.h> using namespace std; int main () { string s=" ** string deleted for forum sanity **"; int j=s....

I have to say, figuring this one out was an awesome experience in de-bugging the various programs I produced to tackle it, but I still cant help wondering whether there's some mathematical way of attacking the problem... anyone with a good knowledge of the topic, I'd love a PM about deriving answers...

Haha, I've been using these crypto chalanges as motivation and goal setting for learning my way through c++ . I spent some time on this one thinking the wrong way , and the output my code gave me (as a modified version of other programs I wrote for cyphers) just underlined that mistake.... made me l...

Used the same solution as the last one; took out the curveball elements in a hex editor. Huzzah, I understand png a bit more. Actually, as mundane as it is, these have been pretty satisfying to solve.

I found some research on png files helped explain why the colours were distorted. My solution was definitely roundabout, could have done it much simpler, but still, explains thecolour issues.