Objectives
The functional specification is a high-level description of the user-visible interface and behaviour of the TSF. It is an instantiation of the TOE security functional requirements. The functional specification has to show that all the TOE security functional requirements are addressed.
Component levelling
The components in this family are levelled on the basis of the degree of formalism required of the functional specification, and the degree of detail provided for the external interfaces to the TSF.
Application notes
The ADV_FSP.*.2E elements within this family define a requirement that the evaluator determine that the functional specification is an accurate and complete instantiation of the TOE security functional requirements. This provides a direct correspondence between the TOE security functional requirements and the functional specification, in addition to the pairwise correspondences required by the ADV_RCR family. It is expected that the evaluator will use the evidence provided in ADV_RCR as an input to making this determination, and the requirement for completeness is intended to be relative to the level of abstraction of the functional specification.
For ADV_FSP.1.3C, it is intended that sufficient information is provided in the functional specification to understand how the TOE security functional requirements have been addressed, and to enable the specification of tests which reflect the TOE security functional requirements in the ST. It is not necessarily the case that such testing will cover all possible return values and error messages which could be generated at the interface, but the information provided should make clear the results of using an interface in the case of success and the most common instances of failure.
ADV_FSP.2.3C introduces a requirement for a complete presentation of the functional interface. This will provide the necessary detail for supporting both thorough testing of the TOE and the assessment of vulnerabilities.
In the context of the level of formality of the functional specification, informal, semiformal and formal are considered to be hierarchical in nature. Thus, ADV_FSP.1.1C and ADV_FSP.2.1C may also be met with either a semiformal or formal functional specification, provided that it is supported by informal, explanatory text where appropriate. In addition, ADV_FSP.3.1C may also be met with a formal functional specification.