PROGRAMMING - Hacking: The Art of Exploitation - page 6

can be written to accomplish any given task, but most of these solutions are
unnecessarily large, complex, and sloppy. The few solutions that remain
are small, efficient, and neat. Programs that have these qualities are said to
have elegance , and the clever and inventive solutions that tend to lead to
this efficiency are called hacks . Hackers on both sides of programming
appreciate both the beauty of elegant code and the ingenuity of clever hacks.
In the business world, more importance is placed on churning out func-
tional code than on achieving clever hacks and elegance. Because of the
tremendous exponential growth of computational power and memory,
spending an extra five hours to create a slightly faster and more memory-
efficient piece of code just doesn't make business sense when dealing with
modern computers that have gigahertz of processing cycles and gigabytes of
memory. While time and memory optimizations go without notice by all but
the most sophisticated of users, a new feature is marketable. When the
bottom line is money, spending time on clever hacks for optimization just
doesn't make sense.
True appreciation of programming elegance is left for the hackers:
computer hobbyists whose end goal isn't to make a profit but to squeeze
every possible bit of functionality out of their old Commodore 64s, exploit
writers who need to write tiny and amazing pieces of code to slip through
narrow security cracks, and anyone else who appreciates the pursuit and the
challenge of finding the best possible solution. These are the people who get
excited about programming and really appreciate the beauty of an elegant
piece of code or the ingenuity of a clever hack. Since an understanding of
programming is a prerequisite to understanding how programs can be
exploited, programming is a natural starting point.

0x210 What Is Programming?

Programming is a very natural and intuitive concept. A program is nothing
more than a series of statements written in a specific language. Programs are
everywhere, and even the technophobes of the world use programs every day.
Driving directions, cooking recipes, football plays, and DNA are all types of
programs. A typical program for driving directions might look something
like this:

Start out down Main Street headed east. Continue on Main Street until you see
a church on your right. If the street is blocked because of construction, turn
right there at 15th Street, turn left on Pine Street, and then turn right on
16th Street. Otherwise, you can just continue and make a right on 16th Street.
Continue on 16th Street, and turn left onto Destination Road. Drive straight
down Destination Road for 5 miles, and then you'll see the house on the right.
T he address is 743 Destination Road.

Anyone who knows English can understand and follow these driving
directions, since they're written in English. Granted, they're not eloquent,
but each instruction is clear and easy to understand, at least for someone
who reads English.