Portal to the Future
Posted: Sun Aug 30, 2009 7:42 am
Well it was easy just edit the class version. Anyone solved it another way?
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Posted: Thu Oct 21, 2010 9:22 pm
Nope, did it just the same. I took longer than needed because I had recently switched to a new hex editor, and because not being used to it yet, unintentionally inserted another byte after the major version – shit happens…
Posted: Thu Mar 22, 2012 10:20 am
Did the same. Reengeneering with 'http://java.decompiler.free.fr/' did
not work for this class file. ( It worked for all the other class-files here -- hint !! )
Ok - all the other class-files i found so far....
not work for this class file. ( It worked for all the other class-files here -- hint !! )
Ok - all the other class-files i found so far....
Posted: Fri Mar 23, 2012 1:12 am
You probably did not solve enough challenges to be able to speak about "all the other" java classesmagnus wrote:Did the same. Reengeneering with 'http://java.decompiler.free.fr/' did
not work for this class file. ( It worked for all the other class-files here -- hint !! )
There are java programs here that resist any decompiler 
Posted: Tue Oct 01, 2013 7:16 pm
Oh, right. Modifying the major version. That's a thing I could've done instead.
I pulled it through a decompiler, which couldn't make sense of the main routine used to calculate the answer. So I hand-decoded the bytecode for that one method. Then a couple of constants were missing (35 and 85), so I hand-decoded the constants table as well. I worked the loop back in, and then rewrote the assignments to refer to the 0xFFFF0000 bytes and the 0x0000FFFF bytes explicitly. This removed some variable dependencies, and the entire loop body was then of the form "result = result + blahblahblah", independent of the looping variable. So that's a multiplication. The result of the program was simple enough to do by calculator as well.
Should've modified the major version. Still, diving into the class file has been educational, so it wasn't a complete waste of time.
I pulled it through a decompiler, which couldn't make sense of the main routine used to calculate the answer. So I hand-decoded the bytecode for that one method. Then a couple of constants were missing (35 and 85), so I hand-decoded the constants table as well. I worked the loop back in, and then rewrote the assignments to refer to the 0xFFFF0000 bytes and the 0x0000FFFF bytes explicitly. This removed some variable dependencies, and the entire loop body was then of the form "result = result + blahblahblah", independent of the looping variable. So that's a multiplication. The result of the program was simple enough to do by calculator as well.
Should've modified the major version. Still, diving into the class file has been educational, so it wasn't a complete waste of time.
Posted: Sun Apr 27, 2014 6:43 pm
Much easier when one already did a lot of work on PP4
Posted: Sun Apr 27, 2014 10:02 pm
What's a PP4?Hippo wrote:Much easier when one already did a lot of work on PP4
Posted: Mon May 05, 2014 2:08 pm
Protected password 4.AMindForeverVoyaging wrote:What's a PP4?Hippo wrote:Much easier when one already did a lot of work on PP4