WSCSetProviderInfo function (ws2spi.h)

Syntax

int WSCSetProviderInfo(
  [in]  LPGUID                 lpProviderId,
  [in]  WSC_PROVIDER_INFO_TYPE InfoType,
  [in]  PBYTE                  Info,
  [in]  size_t                 InfoSize,
  [in]  DWORD                  Flags,
  [out] LPINT                  lpErrno
);

Parameters

[in] lpProviderId

A pointer to a globally unique identifier (GUID) for the provider.

[in] InfoType

The information class to be set for this LSP protocol entry.

[in] Info

A pointer to a buffer that contains the information class data to set for the LSP protocol entry.

[in] InfoSize

The size, in bytes, of the buffer pointed to by the Info parameter.

[in] Flags

The flags used to modify the behavior of the WSCSetProviderInfo function call.

[out] lpErrno

A pointer to the error code if the function fails.

Return value

If no error occurs, WSCSetProviderInfo returns ERROR_SUCCESS (zero). Otherwise, it returns SOCKET_ERROR, and a specific error code is returned in the lpErrno parameter.

Remarks

WSCSetProviderInfo is used to set the information class data for a layered service provider. When the InfoType parameter is set to ProviderInfoLspCategories, on success WSCSetProviderInfo sets appropriate LSP category flags implemented by the provider based on the value passed in the Info parameter.

Winsock 2 accommodates layered protocols. A layered protocol is one that implements only higher level communications functions, while relying on an underlying transport stack for the actual exchange of data with a remote endpoint. An example of a layered protocol or layered service provider would be a security layer that adds protocol to the connection establishment process in order to perform authentication and to establish a mutually agreed upon encryption scheme. Such a security protocol would generally require the services of an underlying reliable transport protocol such as TCP or SPX. The term base protocol refers to a protocol such as TCP or SPX which is capable of performing data communications with a remote endpoint. The term layered protocol is used to describe a protocol that cannot stand alone. A protocol chain would then be defined as one or more layered protocols strung together and anchored by a base protocol. A base protocol has the ChainLen member of the WSAPROTOCOL_INFO structure set to BASE_PROTOCOL which is defined to be 1. A layered protocol has the ChainLen member of the WSAPROTOCOL_INFO structure set to LAYERED_PROTOCOL which is defined to be zero. A protocol chain has the ChainLen member of the WSAPROTOCOL_INFO structure set to greater than 1.

During LSP initialization, the LSP must provide pointers to a number of Winsock SPI functions. These functions will be called during normal processing by the layer directly above the LSP (either another LSP or Ws2_32.dll).

An LSP that implements an installable file system (IFS) can selectively choose to provide pointers to functions which are implemented by itself, or pass back the pointers provided by the layer directly below the LSP. Non-IFS LSPs, because they provide their own handles, must implement all of the Winsock SPI functions. This is because each SPI will require the LSP to map all of the socket handles it created to the socket handle of the lower provider (either another LSP or the base protocol).

However, all LSPs perform their specific work by doing extra processing on only a subset of the Winsock SPI functions.

It is possible to define LSP categories based upon the subset of SPI functions an LSP implements and the nature of the extra processing performed for each of those functions.

By classifying LSPs, as well as classifying applications which use Winsock sockets, it becomes possible to selectively determine if an LSP should be involved in a given process at runtime.

On Windows Vista and later, an LSP can be classified based on how it interacts with Windows Sockets calls and data. An LSP category is an identifiable group of behaviors on a subset of Winsock SPI functions. For example, an HTTP content filter would be categorized as a data inspector (the LSP_INSPECTOR category). The LSP_INSPECTOR category will inspect, but not alter, parameters to data transfer SPI functions. An application can query for the category of an LSP and choose to not load the LSP based on the LSP category and the application's set of permitted LSP categories.

The following table lists categories into which an LSP can be classified.

If an LSP does not have category set, it is considered to be in the All Other category. This LSP category will not be loaded in services or system processes (for example, lsass, winlogon, and many svchost processes).

The WSCSetProviderInfo function can only be called by a user logged on as a member of the Administrators group. If WSCSetProviderInfo is called by a user that is not a member of the Administrators group, the function call will fail and WSANO_RECOVERY is returned in the lpErrno parameter. This function can also fail because of user account control (UAC). If an application that contains this function is executed by a user logged on as a member of the Administrators group other than the built-in Administrator, this call will fail unless the application has been marked in the manifest file with a requestedExecutionLevel set to requireAdministrator. If the application on Windows Vista or Windows Server 2008 lacks this manifest file, a user logged on as a member of the Administrators group other than the built-in Administrator must then be executing the application in an enhanced shell as the built-in Administrator (RunAs administrator) for this function to succeed.

Requirements

See also

Categorizing Layered Service Providers and Applications WSAPROTOCOL_INFO WSCGetApplicationCategory WSCGetProviderInfo WSCSetApplicationCategory WSC_PROVIDER_INFO_TYPE