Built-in callout identifiers

The identifiers for the callouts that are built into the Windows Filtering Platform are each represented by a GUID. These identifiers are defined as follows.

Note

The V4 and V6 suffixes at the end of the callout identifiers indicate whether the callout is for the IPv4 network stack or the IPv6 network stack.

Built-in callout identifier	Callout description
FWPM_CALLOUT_IPSEC_INBOUND_TRANSPORT_V4 FWPM_CALLOUT_IPSEC_INBOUND_TRANSPORT_V6	Verifies that each received packet that is supposed to arrive over a transport mode security association arrives securely. This callout is applicable at the transport layer.
FWPM_CALLOUT_IPSEC_OUTBOUND_TRANSPORT_V4 FWPM_CALLOUT_IPSEC_OUTBOUND_TRANSPORT_V6	Indicates to IPsec the outbound traffic that must be secured over transport mode security associations. This callout is applicable at the transport layer.
FWPM_CALLOUT_IPSEC_INBOUND_TUNNEL_V4 FWPM_CALLOUT_IPSEC_INBOUND_TUNNEL_V6	Verifies that each received packet that is supposed to arrive over a tunnel mode security association arrives securely. This callout is applicable at the transport layer.
FWPM_CALLOUT_IPSEC_OUTBOUND_TUNNEL_V4 FWPM_CALLOUT_IPSEC_OUTBOUND_TUNNEL_V6	Indicates to IPsec the outbound traffic that must be secured over tunnel mode security associations. This callout is applicable at the transport layer.
FWPM_CALLOUT_IPSEC_FORWARD_INBOUND_TUNNEL_V4 FWPM_CALLOUT_IPSEC_FORWARD_INBOUND_TUNNEL_V6	Verifies that each received packet that is supposed to arrive over a tunnel mode security association arrives securely. This callout is applicable at the forward layer.
FWPM_CALLOUT_IPSEC_FORWARD_OUTBOUND_TUNNEL_V4 FWPM_CALLOUT_IPSEC_FORWARD_OUTBOUND_TUNNEL_V6	Indicates to IPsec the outbound traffic that must be secured over a tunnel mode security association. This callout is applicable at the forward layer.
FWPM_CALLOUT_IPSEC_INBOUND_INITIATE_SECURE_V4 FWPM_CALLOUT_IPSEC_INBOUND_INITIATE_SECURE_V6	Verifies that each incoming connection that is supposed to arrive securely does so. This callout is applicable at the ALE accept layer.
FWPM_CALLOUT_IPSEC_ALE_CONNECT_V4 FWPM_CALLOUT_IPSEC_ALE_CONNECT_V6	Applies IPsec policy modifiers to client applications.
FWPM_CALLOUT_WFP_TRANSPORT_LAYER_V4_SILENT_DROP FWPM_CALLOUT_WFP_TRANSPORT_LAYER_V6_SILENT_DROP	Silently drops all incoming packets for which TCP does not have a listening endpoint. This callout is applicable at the inbound transport layer.
FWPM_CALLOUT_TCP_CHIMNEY_CONNECT_LAYER_V4 FWPM_CALLOUT_TCP_CHIMNEY_CONNECT_LAYER_V6	Enables or disables TCP chimney offload for each outgoing connection.
FWPM_CALLOUT_TCP_CHIMNEY_ACCEPT_LAYER_V4 FWPM_CALLOUT_TCP_CHIMNEY_ACCEPT_LAYER_V6	Enables or disables TCP chimney offload for each incoming connection.