5 ms·
I solved this encrypted BART ad. Can you?
- NateLawson 17y agoI know it is solvable because I've done it. Disclaimer: I did not create it. The source of the ad is one of my customers, although they gave me no hints to solve it.
- tptacek 17y agoYou pretty much gave away the answer with the title of the posting, for what it's worth.
- NateLawson 17y agoThe most important hint is to realize it is encrypted, not a math equation.
- ahlatimer 17y agoThat, along with finding out who Binet is (if you weren't already aware), makes it pretty trivial to solve.
- nabin 17y agoOk so l = map(ord,message) for i in l: a = f(l) And now hat? a is a big integer, chr(a mod 256)? nothing.. :-/
- ahlatimer 17y agoI posted the solution on my blog. If anyone wants to figure it out themselves, then don't read it. http://ahlatimer.wordpress.com/2010/01/12/bart-solution/ http://ahlatimer.wordpress.com/2010/01/12/bart-solution/
- tptacek 17y agoI am really let down by the answer to this poster.
- hyperbovine 17y agoI guess "Come work for Macrovision!" didn't have the geek appeal they were seeking.
- tptacek 17y agoIt should. They have awesome fun problems to solve.
- defen 17y agoI'm sure they do, but solving those problems is a means to an end considered evil (or at least unethical) by many hackers.
- NateLawson 17y agoThat's kind of like saying you'd never work for MSFT or Apple because both create DRM. If you're that kind of absolutist, yes, you don't want to work there. But Rovi is a big company and the Blu-ray content protection system is quite interesting. The ultimate equilibrium they will achieve if they do their job properly is that discs will not be rippable when they first come out, but after a couple months will get cracked. In that time period, the studio makes 90% of their lost revenue and you still have the ability to make backups after a delay. BD+ has had its ups and downs, but I think it has the potential to achieve this. It's more than you can say for most DRM systems. Disclaimer: I am a co-designer of BD+.
- mmastrac 17y agoIf studios wanted to preserve that balance, they'd release keys to decrypt the movies for personal use on a set schedule after release. As it stands right now, users need to hope that someone will manage to "crack" the next BD+ revision (ie: building up the BD+ emulators to a point where they can pass the next set of checks) in order to back up or transcode their disks. At times, the cracking community is further behind than a few months, making these movies useless outside of the standard player. I can't watch Blu-ray movies on my MacBook or iPhone at all without ripping them, one of the reasons I haven't bought a single BR disc to own. If users knew that a key release is coming on a set date, it would remove a lot of the motivation for people to work on cracking BD+.
- kazuya 17y agoIs this Jacques Binet? http://en.wikipedia.org/wiki/Jacques_Philippe_Marie_Binet http://en.wikipedia.org/wiki/Jacques_Philippe_Marie_Binet If so, is it about Fibonacci numbers?