Then the phase defused and the bomb proceeds the next phase

Step 1: Get Your Bomb

Each students will attempt to defuse their own personalized bomb. Each bomb is a Linux binary executable file that has been compiled from a C program. Your bomb will be emailed to your email address that you receive class messages with. It will be delivered as a tar file called bombk.tar, where k is the unique number of your bomb.

Step 2: Defuse Your Bomb

Your job is to defuse the bomb.

The phases get progressively harder to defuse, but the expertise you gain as you move from phase to phase should offset this difficulty.

The bomb ignores blank input lines. If you run your bomb with a command line argument, for example,

Any clarifications and revisions to the assignment will be posted on course website.

You should do the assignment on the class machines. In fact, there is a rumor that Dr. Evil really is evil, and the bomb will always blow up if run elsewhere. There are several other tamper-proofing devices built into the bomb as well, or so they say.

We do make one request, please do not use brute force! You could write a program that will try every possible key to find the right one. But this is no good for several reasons:

• gdb

The GNU debugger, this is a command line debugger tool available on virtually every platform. You can trace through a program line by line, examine memory and registers, look at both the source code and assembly code (we are not giving you the source code for most of your bomb), set breakpoints, set memory watch points, and write scripts. Here are some tips for using gdb.

• objdump -d

Use this to disassemble all of the code in the bomb. You can also just look at individual functions. Reading the assembler code can tell you how the bomb works.

• strings

This utility will display the printable strings in your bomb.