NDIS_TCP_IP_CHECKSUM_OFFLOAD structure (ntddndis.h)
The NDIS_TCP_IP_CHECKSUM_OFFLOAD structure provides checksum task offload information in the NDIS_OFFLOAD structure.
Syntax
typedef struct _NDIS_TCP_IP_CHECKSUM_OFFLOAD {
struct {
ULONG Encapsulation;
ULONG IpOptionsSupported : 2;
ULONG TcpOptionsSupported : 2;
ULONG TcpChecksum : 2;
ULONG UdpChecksum : 2;
ULONG IpChecksum : 2;
} IPv4Transmit;
struct {
ULONG Encapsulation;
ULONG IpOptionsSupported : 2;
ULONG TcpOptionsSupported : 2;
ULONG TcpChecksum : 2;
ULONG UdpChecksum : 2;
ULONG IpChecksum : 2;
} IPv4Receive;
struct {
ULONG Encapsulation;
ULONG IpExtensionHeadersSupported : 2;
ULONG TcpOptionsSupported : 2;
ULONG TcpChecksum : 2;
ULONG UdpChecksum : 2;
} IPv6Transmit;
struct {
ULONG Encapsulation;
ULONG IpExtensionHeadersSupported : 2;
ULONG TcpOptionsSupported : 2;
ULONG TcpChecksum : 2;
ULONG UdpChecksum : 2;
} IPv6Receive;
} NDIS_TCP_IP_CHECKSUM_OFFLOAD, *PNDIS_TCP_IP_CHECKSUM_OFFLOAD;
Members
IPv4Transmit
A structure within NDIS_TCP_IP_CHECKSUM_OFFLOAD that specifies IPv4 transmit information and that contains the following members:
IPv4Transmit.Encapsulation
Encapsulation settings for IPv4 transmit. For more information about this member, see the following Remarks section.
IPv4Transmit.IpOptionsSupported
A ULONG value that a miniport driver sets to indicate that a miniport adapter can calculate an IP checksum for an IPv4 send packet that contains IP options or to indicate that this capability is enabled or disabled.
IPv4Transmit.TcpOptionsSupported
A ULONG value that a miniport driver sets to indicate that a miniport adapter can calculate a TCP checksum for an IPv4 send packet that contains TCP options or to indicate that this capability is enabled or disabled.
IPv4Transmit.TcpChecksum
A ULONG value that a miniport driver sets to indicate that a miniport adapter can calculate a TCP checksum for an IPv4 send packet. The TCP/IP transport sets this value to enable this capability or to indicate that this capability is enabled or disabled.
IPv4Transmit.UdpChecksum
A ULONG value that a miniport driver sets to indicate that a miniport adapter can calculate a UDP checksum for an IPv4 send packet or to indicate that this capability is enabled or disabled.
IPv4Transmit.IpChecksum
A ULONG value that a miniport driver sets to indicate that a miniport adapter can calculate an IP checksum for an IPv4 send packet or to indicate that this capability is enabled or disabled.
IPv4Receive
A structure within NDIS_TCP_IP_CHECKSUM_OFFLOAD that specifies IPv4 receive information and that contains the following members:
IPv4Receive.Encapsulation
Encapsulation settings for IPv4 receive. For more information about this member, see the following Remarks section.
IPv4Receive.IpOptionsSupported
A ULONG value that a miniport driver sets to indicate that a miniport adapter can validate an IP checksum for an IPv4 receive packet that contains IP options or to indicate that this capability is enabled or disabled.
IPv4Receive.TcpOptionsSupported
A ULONG value that a miniport driver sets to indicate that a miniport adapter can calculate a TCP checksum for an IPv4 receive packet that contains TCP options or to indicate that this capability is enabled or disabled.
IPv4Receive.TcpChecksum
A ULONG value that a miniport driver sets to indicate that a miniport adapter can validate the TCP checksum for an IPv4 receive packet or to indicate that this capability is enabled or disabled.
IPv4Receive.UdpChecksum
A ULONG value that a miniport driver sets to indicate that a miniport adapter can validate an IPv4 receive packet's UDP checksum or to indicate that this capability is enabled or disabled.
IPv4Receive.IpChecksum
A ULONG value that a miniport driver sets to indicate that a miniport adapter can validate an IP checksum for an IPv4 receive packet or to indicate that this capability is enabled or disabled.
IPv6Transmit
A structure within NDIS_TCP_IP_CHECKSUM_OFFLOAD that specifies IPv6 transmit information and that contains the following members:
IPv6Transmit.Encapsulation
Encapsulation settings for IPv6 transmit. For more information about this member, see the following Remarks section.
IPv6Transmit.IpExtensionHeadersSupported
A ULONG value that a miniport driver sets to indicate that the miniport adapter can calculate checksums on IPv6 packets that contain extension headers.
IPv6Transmit.TcpOptionsSupported
A ULONG value that a miniport driver sets to indicate that a miniport adapter can calculate a TCP checksum for an IPv6 send packet that contains TCP options or to indicate that this capability is enabled or disabled.
IPv6Transmit.TcpChecksum
A ULONG value that a miniport driver sets to indicate that a miniport adapter can calculate a TCP checksum for an IPv6 send packet or to indicate that this capability is enabled or disabled.
IPv6Transmit.UdpChecksum
A ULONG value that a miniport driver sets to indicate that a miniport adapter can calculate a UDP checksum for an IPv6 send packet or to indicate that this capability is enabled or disabled.
IPv6Receive
A structure within NDIS_TCP_IP_CHECKSUM_OFFLOAD that specifies IPv6 receive information and that contains the following members:
IPv6Receive.Encapsulation
Encapsulation settings for IPv6 receive. For more information about this member, see the following Remarks section.
IPv6Receive.IpExtensionHeadersSupported
A ULONG value that a miniport driver sets to indicate that the miniport adapter can validate checksums on IPv6 packets that contain extension headers.
IPv6Receive.TcpOptionsSupported
A ULONG value that a miniport driver sets to indicate that a miniport adapter can calculate a checksum for an IPv6 receive packet whose TCP header contains TCP options or to indicate that this capability is enabled or disabled.
IPv6Receive.TcpChecksum
A ULONG value that a miniport driver sets to indicate that a miniport adapter can validate an IPv6 receive packet's TCP checksum or to indicate that this capability is enabled or disabled.
IPv6Receive.UdpChecksum
A ULONG value that a miniport driver sets to indicate that a miniport adapter can validate a UDP checksum for an IPv6 receive packet or to indicate that this capability is enabled or disabled.
Remarks
The NDIS_TCP_IP_CHECKSUM_OFFLOAD structure is used in the Checksum member of the NDIS_OFFLOAD structure. The NDIS_TCP_IP_CHECKSUM_OFFLOAD structure specifies the current or supported services that a miniport adapter provides for calculating IP, TCP, or UDP checksums (or all of them) for send packets and validating such checksums for receive packets.
NDIS_OFFLOAD is used in the NDIS_MINIPORT_ADAPTER_OFFLOAD_ATTRIBUTES structure, NDIS_BIND_PARAMETERS structure, NDIS_FILTER_ATTACH_PARAMETERS structure, OID_TCP_OFFLOAD_CURRENT_CONFIG OID, and the NDIS_STATUS_TASK_OFFLOAD_CURRENT_CONFIG status indication.
For OID_TCP_OFFLOAD_CURRENT_CONFIG, the NDIS_OFFLOAD structure specifies the task offload capabilities that a miniport adapter supports. If the current offloads capabilities change, a miniport driver reports the new capabilities in an NDIS_STATUS_TASK_OFFLOAD_CURRENT_CONFIG status indication.
The Encapsulation members of NDIS_TCP_IP_CHECKSUM_OFFLOAD define the checksum offload encapsulation settings for the miniport adapter.
In response to an OID_TCP_OFFLOAD_CURRENT_CONFIG query request, NDIS provides a bitwise OR of the encapsulation flags, which indicate the supported encapsulation settings, in each of the Encapsulation members. Miniport drivers must provide Ethernet encapsulation (NDIS_ENCAPSULATION_IEEE_802_3). The other types of encapsulation are optional.
For an NDIS_STATUS_TASK_OFFLOAD_CURRENT_CONFIG status indication, the miniport driver provides a bitwise OR of the encapsulation flags, which indicate the current capabilities, in each of the Encapsulation members.
The following flags are defined for the Encapsulation members:
- NDIS_ENCAPSULATION_NOT_SUPPORTED
Specifies that no encapsulation offload is supported. - NDIS_ENCAPSULATION_NULL
Specifies NULL encapsulation. - NDIS_ENCAPSULATION_IEEE_802_3
Specifies IEEE 802.3 encapsulation. - NDIS_ENCAPSULATION_IEEE_802_3_P_AND_Q
Specifies IEEE 802.3p and IEEE 802.3q encapsulation. - NDIS_ENCAPSULATION_IEEE_802_3_P_AND_Q_IN_OOB
Specifies that IEEE 802.3p and IEEE 802.3q encapsulation settings are specified in the NetBufferListInfo member of each NET_BUFFER_LIST structure. - NDIS_ENCAPSULATION_IEEE_LLC_SNAP_ROUTED
Specifies logical link control (LLC) encapsulation for routed protocols, as described in RFC 1483. This flag is also used to indicate Ethernet LLC/SNAP encapsulation.
The meaning of the values in the IpOptionsSupported, TcpOptionsSupported, IpExtensionHeadersSupported, TcpChecksum, UdpChecksum, and IpChecksum members of NDIS_TCP_IP_CHECKSUM_OFFLOAD depends on which OID or status indication includes the task offload structure. These members can have one of the following values:
- NDIS_OFFLOAD_NOT_SUPPORTED
In OID_TCP_OFFLOAD_CURRENT_CONFIG, this value specifies that the miniport adapter does not support the feature that the member specifies. - NDIS_OFFLOAD_SUPPORTED
In OID_TCP_OFFLOAD_CURRENT_CONFIG, this value specifies that the miniport adapter supports the feature that the member specifies. - NDIS_OFFLOAD_SET_OFF
In the NDIS_STATUS_TASK_OFFLOAD_CURRENT_CONFIG status indication, this value specifies that the feature that the member specifies is disabled. - NDIS_OFFLOAD_SET_ON
In the NDIS_STATUS_TASK_OFFLOAD_CURRENT_CONFIG status indication, this value specifies that the feature that the member specifies is enabled.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Supported in NDIS 6.0 and later. |
| Header | ntddndis.h (include Ndis.h) |