FWPM_CALLOUT0 structure (fwpmtypes.h)

  • Article

The FWPM_CALLOUT0 structure stores the state associated with a callout.

Syntax

typedef struct FWPM_CALLOUT0_ {
  GUID               calloutKey;
  FWPM_DISPLAY_DATA0 displayData;
  UINT32             flags;
  GUID               *providerKey;
  FWP_BYTE_BLOB      providerData;
  GUID               applicableLayer;
  UINT32             calloutId;
} FWPM_CALLOUT0;

Members

calloutKey

Uniquely identifies the session.

If the GUID is initialized to zero in the call to FwpmCalloutAdd0, the base filtering engine (BFE) will generate one.

displayData

A FWPM_DISPLAY_DATA0 structure that contains human-readable annotations associated with the callout. The name member of the FWPM_DISPLAY_DATA0 structure is required.

flags

Value Meaning
FWPM_CALLOUT_FLAG_PERSISTENT
 The callout is persistent across reboots. As a result, it can be referenced by boot-time and other persistent filters.
FWPM_CALLOUT_FLAG_USES_PROVIDER_CONTEXT
 The callout needs access to the provider context stored in the filter invoking the callout. If this flag is set, the provider context will be copied from the [FWPM_FILTER0](/windows/desktop/api/fwpmtypes/ns-fwpmtypes-fwpm_filter0) structure to the FWPS_FILTER0 structure. The FWPS_FILTER0 structure is documented in the WDK.
FWPM_CALLOUT_FLAG_REGISTERED
 The callout is currently registered in the kernel. This flag must not be set when adding new callouts. It is used only in querying the state of existing callouts.

providerKey

Uniquely identifies the provider associated with the callout. If the member is non-NULL, only objects associated with the specified provider will be returned.

providerData

A FWP_BYTE_BLOB structure that contains optional provider-specific data that allows providers to store additional context information with the object.

applicableLayer

Specifies the layer in which the callout can be used. Only filters in this layer can invoke the callout. For more information, see Filtering Layer Identifiers.

calloutId

LUID identifying the callout. This is the calloutId stored in the FWPS_ACTION0 structure for filters that invoke a callout. The FWPS_ACTION0 structure is documented in the WDK.

Remarks

The first six members of this structure contain data supplied when adding objects.

The last member, calloutId, provides additional information returned when getting/enumerating objects.

FWPM_CALLOUT0 is a specific implementation of FWPM_CALLOUT. See WFP Version-Independent Names and Targeting Specific Versions of Windows for more information.

Requirements

Requirement Value
Minimum supported client Windows Vista [desktop apps only]
Minimum supported server Windows Server 2008 [desktop apps only]
Header fwpmtypes.h

See also

Windows Filtering Platform API Structures