Subject, object, operation and permission

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(Relationship with the same notions defined in the standard literature was clarified.)
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We use the terms '''subject''', '''object''', '''operation''' and '''permission''' consistently with a standard access control literature.
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== Definition ==
== Definition ==
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== See also ==
== See also ==
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Wikipedia also contains [http://en.wikipedia.org/wiki/Subject_(access_control)#Computer_security similar definitions]. It contains arguable material.
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These are standard notions and they are defined in various other places:
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* in the [http://www.amazon.com/Operating-Systems-Implementation-Prentice-Software/dp/0131429388/ref=sr_1_14?ie=UTF8&s=books&qid=1245137182&sr=8-14 MINIX Book] (Section 5.5)
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* [http://en.wikipedia.org/wiki/Subject_(access_control)#Computer_security in Wikipedia].
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Description of similar notions can be found in Section 5.5 (Protection Mechanisms) in [http://www.amazon.com/Operating-Systems-Implementation-Prentice-Software/dp/0131429388/ref=sr_1_14?ie=UTF8&s=books&qid=1245137182&sr=8-14 The MINIX Book]. They use a term '''domain''' instead of '''subject'''.
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== Notes ==
People (outside capability community) often confuse the following two terms:
People (outside capability community) often confuse the following two terms:

Revision as of 06:11, 20 June 2009

We use the terms subject, object, operation and permission consistently with a standard access control literature.

Definition

From a security point of view, we recognize subjects and objects

Subjects are active entities (e.g. UNIX processes) with some behavior. Subjects can designate objects and try to perform some supported operations with them.

What kind of operations can be performed with an object depends on its type.

In general, the set of existing objects and subjects changes over time.

Permissions is a relation that defines which operations on what objects are permitted for particular subjects. One way how to capture permissions is the protection matrix.

See also

These are standard notions and they are defined in various other places:

Notes

People (outside capability community) often confuse the following two terms:

  • permissions (defined in this article)
  • and authority.

Real security audit cannot be performed without determining the authority of particular subjects.

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