RAS calls the exported function RasEapGetInfo, which is exported by every EAP extension DLL, for an authentication protocol. The EAP extension DLL will be loaded on demand and have this function called. The system will load only those extensions that are currently in use performing authentication. The RasEapGetInfofunction receives a single parameter of type PPP_EAP_INFO. The dwEapTypeIdmember of this structure specifies the authentication protocol, to allow for a single DLL to support more than one protocol. If RasEapGetInforeturns any value other than NO_ERROR, the authentication protocol is assumed to be unavailable.

On return from RasEapGetInfothe PPP_EAP_INFOstructure contains pointers to the RasEapInitialize, RasEapBegin, RasEapMakeMessage, and RasEapEndfunctions in the EAP extension DLL. RAS uses these functions to interoperate with the authentication protocol. RAS immediately calls RasEapInitializefor each authentication protocol, to initialize it. When RAS shuts down it calls RasEapInitializeagain, this time with the fInitializeparameter set to FALSE, indicating that the authentication protocol should shut itself down.

In addition to the mandatory RasEapGetInfo, Windows Embedded CE also provides the following optional functions for exporting an EAP extension DLL:

• RasEapFreeMemory
  
  
• RasEapGetIdentity
  
  
• RasEapInvokeConfigUI
  
  
• RasEapInvokeInteractiveUI
  
  

See Also