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This reminds me of the popular binary bomb lab offered in some computer architecture courses: http://csapp.cs.cmu.edu/public/labs.html http://csapp.cs.cmu.edu/p

by wyc 12y ago

This reminds me of the popular binary bomb lab offered in some computer architecture courses: http://csapp.cs.cmu.edu/public/labs.html http://csapp.cs.cmu.edu/public/labs.html

doktrin 12y ago
These are fantastic labs. I took 15-213 at CMU while already working as a software developer. It was still tons of fun and quite educational.
mathrat 12y ago
Haha, if that's the one I remember you could completely trivialize that lab by fiddling with the program counter in gdb (skipping the line that sets off the bomb). Don't know if they were able to fix that in later versions of the lab. Good times, thanks for reminding me.
- elektronjunge 12y ago
  When I did that, it seemed like it was intentional. You could only get to the portions that signal success to the server by cracking parts of the bomb which was what we were graded on. The "don't let it explode" part was really the hey here's how you can use gdb to stop your program before it does anything serious.
  - CocaKoala 12y ago
    Yeah, I thought that's how everybody did it; when my class was assigned the project, we lost half a percentage point off our final grade for each time the bomb exploded. We very quickly learned to do things like "b explode_bomb".
  - mathrat 12y ago
    So if I recall, you were supposed to have to do a lot of investigative work to bypass stuff. There were several different "levels" that got progressively harder to crack. But there was nothing that stopped you from moving the program counter directly to the code that signals success. Which is what we did. Every level, exactly the same: fire it up, move program counter, send the success notice, finished!
- davesque 12y ago
  That was the point. When I did them, the TA encouraged us to do that. I'm pretty sure they had other measures in place that would have made it hard to fake an authentic success signal to the server. Furthermore, if you sent a corrupted one, you'd lose all credit for the assignment.
CocaKoala 12y ago
Those labs (specifically the binary bomb, buffer bomb, and malloc) were probably the most influential projects I ever did in terms of my career development. Great fun.
mahmoudimus 12y ago
I loved this - a lot of the students really struggled but I already had background in reverse engineering, it was right down my alley. I absolutely loved this and for a long time, it's what I wanted to do professionally.
davesque 12y ago
Yep, did those at University of Colorado Boulder.
- jeorgun 12y ago
  Small world— I've just started this exact assignment at CU. Kind of a neat coincidence seeing it discussed here.
  - davesque 12y ago
    Systems with Dr. Han?
    - jeorgun 12y ago
      That's the one!
vedran 12y ago
That lab was the most fun I've ever had with a homework assignment (too bad my own school didn't offer it...). I got it off the CMU website as well. A couple of years ago I did a (mostly) full walkthrough of the Binary Bomb, and it still gets a lot of hits during the semester. If anyone is curious: http://www.vedranb.com/post/19338235616/phase-1 http://www.vedranb.com/post/19338235616/phase-1

by wyc 12y ago

This reminds me of the popular binary bomb lab offered in some computer architecture courses: http://csapp.cs.cmu.edu/public/labs.html http://csapp.cs.cmu.edu/public/labs.html

doktrin 12y ago

These are fantastic labs. I took 15-213 at CMU while already working as a software developer. It was still tons of fun and quite educational.

mathrat 12y ago

Haha, if that's the one I remember you could completely trivialize that lab by fiddling with the program counter in gdb (skipping the line that sets off the bomb). Don't know if they were able to fix that in later versions of the lab. Good times, thanks for reminding me.

elektronjunge 12y ago
When I did that, it seemed like it was intentional. You could only get to the portions that signal success to the server by cracking parts of the bomb which was what we were graded on. The "don't let it explode" part was really the hey here's how you can use gdb to stop your program before it does anything serious.
- CocaKoala 12y ago
  Yeah, I thought that's how everybody did it; when my class was assigned the project, we lost half a percentage point off our final grade for each time the bomb exploded. We very quickly learned to do things like "b explode_bomb".
- mathrat 12y ago
  So if I recall, you were supposed to have to do a lot of investigative work to bypass stuff. There were several different "levels" that got progressively harder to crack. But there was nothing that stopped you from moving the program counter directly to the code that signals success. Which is what we did. Every level, exactly the same: fire it up, move program counter, send the success notice, finished!
davesque 12y ago
That was the point. When I did them, the TA encouraged us to do that. I'm pretty sure they had other measures in place that would have made it hard to fake an authentic success signal to the server. Furthermore, if you sent a corrupted one, you'd lose all credit for the assignment.

CocaKoala 12y ago

Those labs (specifically the binary bomb, buffer bomb, and malloc) were probably the most influential projects I ever did in terms of my career development. Great fun.

mahmoudimus 12y ago

I loved this - a lot of the students really struggled but I already had background in reverse engineering, it was right down my alley. I absolutely loved this and for a long time, it's what I wanted to do professionally.

davesque 12y ago

Yep, did those at University of Colorado Boulder.

jeorgun 12y ago
Small world— I've just started this exact assignment at CU. Kind of a neat coincidence seeing it discussed here.
- davesque 12y ago
  Systems with Dr. Han?
  - jeorgun 12y ago
    That's the one!

vedran 12y ago

That lab was the most fun I've ever had with a homework assignment (too bad my own school didn't offer it...). I got it off the CMU website as well. A couple of years ago I did a (mostly) full walkthrough of the Binary Bomb, and it still gets a lot of hits during the semester. If anyone is curious: http://www.vedranb.com/post/19338235616/phase-1 http://www.vedranb.com/post/19338235616/phase-1