Microsoft Internet Security and Acceleration Server 2004 SDK

SF_REQ_ADD_HEADERS_ON_DENIAL

The SF_REQ_ADD_HEADERS_ON_DENIAL form of the ServerSupportFunction callback function allows your Web filter to add specified headers to the server error response, in the event that the HTTP request is denied because authentication failed. This allows an authentication filter to advertise its services without filtering every request.

Note  This support function will not work properly if called during or after the processing of SF_NOTIFY_SEND_RESPONSE or SF_NOTIFY_ACCESS_DENIED notifications.

BOOL WINAPI * ServerSupportFunction(
  struct _HTTP_FILTER_CONTEXT* pfc,
  enum SF_REQ_TYPE sfReq,
  PVOID pData,
  DWORD ul1,
  DWORD ul2
);

Parameters

pfc
Pointer to the HTTP_FILTER_CONTEXT data structure that is associated with the current, active HTTP session. Pass the filter context in this parameter.
sfReq
Specifies the particular support function that is to be executed by the ISA Server Web filter, in this case, SF_REQ_ADD_HEADERS_ON_DENIAL.
pData
Pointer to a null-terminated string that specifies one or more HTTP header lines. Each header should be terminated with a carriage return and line feed.
ul1
Unused in this support function.
ul2
Unused in this support function.

Return Values

Returns TRUE if the function succeeded, or FALSE if the function failed.

Remarks

Generally, the HTTP headers should be Proxy-Authenticate headers (forward proxy) or WWW-Authenticate headers (reverse proxy) that specify custom authentication schemes. However, no restriction is placed on which headers can be specified.

The headers are added only for a 401 response in a reverse proxy scenario or a 407 response in a forward proxy scenario.

For more information about the types of event notifications that are sent to Web filters, see Event Notifications.

Requirements

Server: Requires Windows Server 2003 or Windows 2000.
Version: Requires Internet Security and Acceleration Server 2004.
Header: Declared in Wpxhttpfilt.h.

See Also

ServerSupportFunction