52 lines
2.6 KiB
Plaintext
52 lines
2.6 KiB
Plaintext
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FUNGEN4.CVP 910819
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Hiding in System Layers
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One additional use that viral programs can make of operating
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systems is as a source of hiding places.
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Anyone who has ever tried to manage accounts on mainframes or
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local area networks will recognize that there is a constant
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battle between the aspects of security and "user friendliness" in
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computer use. This tension arises from the definition of the two
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functions: if a computer is easy to use, it is easy to misuse.
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If a password is hard to guess, it is hard to remember. If
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access to information is simple for the owner, it is simple for
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the "cracker".
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(This axiom often gives rise to two false "corollaries". First,
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the reverse; that those systems which are difficult to use must
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therefore be more secure; does not hold. Secondly, many assume
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that restricting the availability of information about a system
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will make that system secure. While this strategy will work in
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the short term, its effectiveness as protection is limited.
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Indeed, it often has the unfortunate side effect of restricting
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information to those who should have it, such as systems
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managers, while slowing the "attackers" only marginally.)
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"User friendly" programs and operating systems tend to hide
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information from the user. There are two reasons for this. In
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order to reduce "clutter", and the amount of information that a
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user needs to operate a given system, it is necessary to remove
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options, and therefore, to a certain extent, functionality. A
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user friendly system is also more complex in terms of it's own
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programming. In order for the computer to behave "intuitively",
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it must be able to provide for the many "counter-intuitive" ways
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that people work. Therefore the most basic levels of a graphical
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user interface system tend to be more complex than the
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corresponding levels of a command line interface system, and are
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hidden from the user by additional intervening layers (which also
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tend to add more complexity.)
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The additional layers in an operating system, and the fact that
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a great deal of management takes place automatically, without the
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user's awareness, is an ideal situation for a viral program.
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Since many legitimate and necessary operations and changes are
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performed without the user being aware of it, viral operations
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can also proceed at a level completely hidden from the user.
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Also, because the user is basically unaware of the structure and
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operations of the computer, changes to that structure and
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operation are difficult to detect.
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copyright Robert M. Slade, 1991 FUNGEN4.CVP 910819
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