The FESF Policy Service is the interface between FESF and the components of a Solution that determine Policy. The FESF Policy Service receives requests from the FESF Kernel Mode Components, converts them to the expected format, and passes them to the Client Solution’s Policy DLL. All calls from the FESF Policy Service into the Policy DLL are done via conventional call/return interfaces.
It is important to understand that the only interface from FESF to a Client Solution is via FesfPolicy, which in turn calls the Client Solution’s Policy DLL. While Solution components can call FESF to request information or perform utility functions, all calls that originate from FESF come through FesfPolicy and the Solution’s Policy DLL.
The FESF Policy Service calls entry points in the Policy DLL in the context of a worker thread. These calls are synchronous. That is, the Policy DLL must only return when it has the information requested (or else return an error). When a call to the Policy DLL is made, that call is blocking an associated kernel-mode operation. When the Policy DLL returns from a call, the results are returned by the FESF Policy Service to the FESF Kernel Mode Components.
The source code, and all the items necessary for building FesfPolicy from source, are provided as part of your FESF License. This code is for your reference only. OSR does not support changes or customizations to FesfPolicy.
The specifics of the interface between FesfPolicy and the Client Solution Policy DLL, are described later in this document in the section Policy DLL Callback Function Reference.