PRADIUS_EXTENSION_PROCESS callback function (authif.h)

Note  Internet Authentication Service (IAS) was renamed Network Policy Server (NPS) starting with Windows Server 2008. The content of this topic applies to both IAS and NPS. Throughout the text, NPS is used to refer to all versions of the service, including the versions originally referred to as IAS.
The RadiusExtensionProcess function is an application-defined function and is called by NPS for each authentication or accounting packet that NPS receives from the network access server (NAS).



DWORD PradiusExtensionProcess(
  [in]  const RADIUS_ATTRIBUTE *pAttrs,
  [out] PRADIUS_ACTION pfAction


[in] pAttrs

Pointer to an array of attributes from the request. The array is terminated by an attribute with dwAttrType set to ratMinimum. These attributes should be treated as read-only; they should not be modified by RadiusExtensionProcess. Also, these attributes should not be referenced in any way after RadiusExtensionProcess returns.

[out] pfAction

Pointer to a value of type RADIUS_ACTION, initially set to raContinue. This parameter specifies the action that NPS should take in response to an Access-Request.

Return value

If the function succeeds, the return value is NO_ERROR.

If the function fails, the return value should be an appropriate error code from Winerror.h.


If the return value is anything other than NO_ERROR, NPS discards the request.

NPS supports multiple Extension DLLs. NPS calls RadiusExtensionProcess for each of the DLLs listed in the registry. For more information see Setting Up the Extension DLLs.

The Extension DLL may export RadiusExtensionProcessEx instead of RadiusExtensionProcess. The Extension DLL may export RadiusExtensionProcess2.

For more information on the use of this function, see NPS Extensions Process.


Minimum supported client None supported
Minimum supported server Windows Server 2008
Target Platform Windows
Header authif.h

See also

About NPS Extensions

NPS Extensions Functions

NPS Extensions Reference