Buffer
Overflow Intro. ©2002, Jedidiah R. Crandall, Susan L. Gerhart, Jan G.
Hogle.
http://sfsecurity.pr.erau.edu
Glossary
Compiled – A compiler takes the
source code a programmer has written and turns it into code text that a
computer can easily execute. Code text is a sequence of instructions
for the computer stored in memory.
Instruction – An instruction tells the computer what to do, but it is
very low-level. Unlike source
code, it works at the microprocessor level
telling the computer what elementary steps to take to execute the program.
Source code – this is the code that
the programmer writes in a high-level language like Java, BASIC, or, in this case, C. A
high-level language is one that humans can easily read and understand.
Execute – To execute the program
means to “run” it. The two terms
can be used interchangeably. To
execute an instruction means to do it. It is the process of seeing what the
instruction is, and then doing it.
Jump – A jump occurs when the
computer is told to start executing instructions somewhere else besides the
next instruction after the current one
being executed.
Program counter – The instructions
are stored as a sequence of numbers in the computer just like anything
else. The computer usually executes one instruction after
another unless it is told to jump somewhere else.
The program counter keeps track of what
instruction in memory is being executed at any given time.
Subroutine – Good programmers break
they’re program up into smaller steps called subroutines. A program to make coffee could be broken up into preparing the filter,
putting water in the coffee maker, and turning the coffee maker on.
Each of these subroutines can be broken down into more subroutines. Putting water in the coffee maker could be broken down into get a cup, turn on
the sink, put the cup under the sink, turn off the sink when the cup is full…