FWPS_FILTER1 structure (fwpstypes.h)
The FWPS_FILTER1 structure defines a run-time filter in the filter engine. FWPS_FILTER0 is available.
Syntax
typedef struct FWPS_FILTER1_ {
UINT64 filterId;
FWP_VALUE0 weight;
UINT16 subLayerWeight;
UINT16 flags;
UINT32 numFilterConditions;
FWPS_FILTER_CONDITION0 *filterCondition;
FWPS_ACTION0 action;
UINT64 context;
FWPM_PROVIDER_CONTEXT1 *providerContext;
} FWPS_FILTER1;
Members
filterId
A run-time identifier that identifies the filter in the filter engine.
weight
An FWP_VALUE0 structure that contains a value that specifies the filter's importance in relation to other filters in the filter engine. Filters with a higher weight value are invoked first. The data type specified in the FWP_VALUE0 structure is either FWP_UINT64 or FWP_EMPTY. If the data type specified in the FWP_VALUE0 structure is FWP_EMPTY, the filter engine automatically assigns a weight to the filter based on how specific the filter tests the data compared to the other filters in the filter engine.
subLayerWeight
A value that specifies the importance of the filter's sublayer in relation to the other sublayers in the filter engine. Filters that are located in a sublayer with a higher subLayerWeight value are invoked first.
flags
Flags that specify actions that a callout's classifyFn1 callout function should take when processing network data. Possible flags are:
Value | Meaning |
---|---|
FWPS_FILTER_FLAG_CLEAR_ACTION_RIGHT | This flag indicates to a callout's classifyFn0 callout function that it should always clear the FWPS_RIGHT_ACTION_WRITE flag when it returns either FWP_ACTION_BLOCK or FWP_ACTION_PERMIT for the suggested action. If this flag is not set, a callout's classifyFn0 callout function should only clear the FWPS_RIGHT_ACTION_WRITE flag when it returns FWP_ACTION_BLOCK for the suggested action. |
FWPS_FILTER_FLAG_PERMIT_IF_CALLOUT_UNREGISTERED | This flag indicates to a callout's classifyFn0 callout function that if the callout is not registered, the callout should be treated as a permit filter. |
numFilterConditions
The number of FWPS_FILTER_CONDITION0 structures in the array pointed to by the filterCondition member. This member can be zero.
filterCondition
A pointer to an array of FWPS_FILTER_CONDITION0 structures. These structures define the run-time filtering conditions for the filter. If the numFilterConditions member is zero, then this pointer will be NULL.
action
An FWPS_ACTION0 structure that specifies the action that the filter should take if all of the filter's filtering conditions are true.
context
A context value that is associated with the filter. A callout can set this member to point to a callout driver-supplied context structure from within the callout driver's notifyFn1 callout function when the filter is added to the filter engine. This context structure, which is opaque to the filter engine, can be used by the callout driver's classifyFn1 callout function to preserve any driver-specific data or state information between calls by the filter engine to the callout driver's classifyFn1 callout function.
providerContext
A pointer to the provider context, which is formatted as a FWPM_PROVIDER_CONTEXT1 structure. If the filter uses a callout, and the callout has the FWPM_CALLOUT_FLAG_USES_PROVIDER_CONTEXT flag set, this member will contain the provider context from the corresponding FWPM_FILTER0 structure. Otherwise, this parameter is NULL.
Remarks
The filter engine passes a pointer to an FWPS_FILTER1 structure to a callout's notifyFn1 and classifyFn1 callout functions.
A filter's action is performed only if all of the filter's filtering conditions are true. If no filtering conditions are specified in the filter, then the specified action is always performed.
The ProviderContext member provides a mechanism for a callout driver to retrieve provider contexts without calling the base filtering engine (BFE).
Requirements
Requirement | Value |
---|---|
Minimum supported client | Available starting with Windows 7. |
Header | fwpstypes.h (include Fwpsk.h) |