Windows 7 Keygen
Windows 7 will be deployed on October 22nd 2009.
It will will probably have a bunch of Keygens out on the web soon after it is released.
A Keygen (a portmanteau
of "key generator") is a small program that will generate a
CD key or serial/registration number for a piece of software
or cryptographic algorithm.
Keygens are made available by software cracking groups for
free download on various websites dedicated to software
piracy.
Typically software requests a serial number only during
installation. The installation software applies an algebraic
expression to the key entered to validate the key. As an
example, the algorithm may define that a key entered must
contain 5 numbers that have a checksum of 25, and that the
key must also contain 3 letters that, when mapped into their
numerical equivalents, have a sum of 42.
In order to write a Keygen, the author typically uses a
disassembler to look at the raw assembly code of the program
they are writing the Keygen for, checking either the
software itself or the installer. Once they have access to
the program's code, they can locate the subroutine(s)
responsible for verifying that the key entered is valid.
Using this knowledge, they can reverse engineer the
algorithm used to generate valid keys, which is then
incorporated into the Keygen.
Aside from ethics and legality (addressed below), there are
two major issues in using Keygens: Product activation and
online key verification.
Keys generated with a key generator may not work with
software that is used online, including downloading software
updates. This is because the user must confirm their serial
number every time the software connects to the server, and
the key may be invalid for various reasons.
One reason is
that the cracker may have misinterpreted the original
algorithm, creating a key that was "good enough" to let the
software be installed, but not letting all possible future
generated keys be valid. Another reason may be that the
software developers only accept keys that they know were
distributed with the media during production, or had been
issued with an online registration, causing a
cryptographically correct key to still be denied.
A third reason could be a secondary unpublished algorithm
that is used by the vendor, e.g., to extend the previous
example, the characters 0, 7, 9, C, and K are never allowed.
The software that confirms the key on the user's machine
does not know these numbers and characters are not allowed,
and will accept the Keygen output, but the online
confirmation fails.
One final reason, used primarily with
games with online support, is that the Keygen creates a
valid key, but the key is already in use by either the
person who is using the key legally or someone whose Keygen
program generated the same key. Another major issue is that
Keygen software, like any other software obtained from an
unverifiable source, can contain viruses or Trojan Horses.
*from Windows Vista Update*
