Topic: security by access functions

topics > computer science > Group: security

program module

interface between program modules
information hiding
variable as function that accesses an object's value


Object integrity can be protected by access functions specified through a cluster. Once the cluster is certified correct the implemented objects are protected. Users can access and modify the objects only through access functions provided by the cluster. Operations as well as objects may be protected by access functions. This allows operations to be partially defined while the accessing function is always defined. (cbb 5/80)
Subtopic: no knowledge of use up

Quote: higher-order-software algorithms never have knowledge of their users [»hamiM3_1976]
Quote: the programmer of a module should not make assumptions about its use; use private storage and treat parameters with suspicion [»morrJH10_1973]

Subtopic: protected access to data up

Quote: use private storage to maintain the integrity of a data structure
QuoteRef: morrJH1_1973 ;;16 protect an object by making public only a restrictive accessing function
Quote: if restrict access to a data structure then only member functions can modify the data, cause illegal values, and define how to use the data [»stroB_1991]
Quote: a class member can be 'private', 'protected',or 'public'. Private members implement a class and protected members implement derived classes [»stroB_1991]
Quote: can attach protection to the object rather than the domain; use a procedure to control access to the object [»lampBW3_1971]

Subtopic: other uses of access functions up

Quote: every module only controls access rights to input variables and to output of immediate sub-functions [»hamiM3_1976, OK]
Quote: prevent division by zero in unused branch by using access functions to delay execution [»landPJ_1966, OK]
QuoteRef: robiL9_1975 ;;9 derived value access generated from underived values (no initialization) for access protection in operating system

Related Topics up

Group: program module   (10 topics, 336 quotes)

Topic: interface between program modules (55 items)
Topic: information hiding (50 items)
Topic: variable as function that accesses an object's value
(21 items)

Updated barberCB 1/05
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