/*++
Copyright (c) 1995-1996 Microsoft Corporation
Module Name:
httpfilt.h
Abstract:
This module contains the Microsoft HTTP filter extension info
Revision History:
--*/
#ifndef _HTTPFILT_H_
#define _HTTPFILT_H_
#ifdef __cplusplus
extern "C" {
#endif
//
// Current version of the filter spec is 2.0
//
#define HTTP_FILTER_REVISION MAKELONG( 0, 2);
#define SF_MAX_USERNAME (256+1)
#define SF_MAX_PASSWORD (256+1)
#define SF_MAX_FILTER_DESC_LEN (256+1)
//
// These values can be used with the pfnSFCallback function supplied in
// the filter context structure
//
enum SF_REQ_TYPE
{
//
// Sends a complete HTTP server response header including
// the status, server version, message time and MIME version.
//
// Server extensions should append other information at the end,
// such as Content-type, Content-length etc followed by an extra
// '\r\n'.
//
// pData - Zero terminated string pointing to optional
// status string (i.e., "401 Access Denied") or NULL for
// the default response of "200 OK".
//
// ul1 - Zero terminated string pointing to optional data to be
// appended and set with the header. If NULL, the header will
// be terminated with an empty line.
//
SF_REQ_SEND_RESPONSE_HEADER,
//
// If the server denies the HTTP request, add the specified headers
// to the server error response.
//
// This allows an authentication filter to advertise its services
// w/o filtering every request. Generally the headers will be
// WWW-Authenticate headers with custom authentication schemes but
// no restriction is placed on what headers may be specified.
//
// pData - Zero terminated string pointing to one or more header lines
// with terminating '\r\n'.
//
SF_REQ_ADD_HEADERS_ON_DENIAL,
//
// Only used by raw data filters that return SF_STATUS_READ_NEXT
//
// ul1 - size in bytes for the next read
//
SF_REQ_SET_NEXT_READ_SIZE,
//
// Used to indicate this request is a proxy request
//
// ul1 - The proxy flags to set
// 0x00000001 - This is a HTTP proxy request
//
//
SF_REQ_SET_PROXY_INFO,
//
// Returns the connection ID contained in the ConnID field of an
// ISAPI Application's Extension Control Block. This value can be used
// as a key to cooridinate shared data between Filters and Applications.
//
// pData - Pointer to DWORD that receives the connection ID.
//
SF_REQ_GET_CONNID
};
//
// These values are returned by the filter entry point when a new request is
// received indicating their interest in this particular request
//
enum SF_STATUS_TYPE
{
//
// The filter has handled the HTTP request. The server should disconnect
// the session.
//
SF_STATUS_REQ_FINISHED = 0x8000000,
//
// Same as SF_STATUS_FINISHED except the server should keep the TCP
// session open if the option was negotiated
//
SF_STATUS_REQ_FINISHED_KEEP_CONN,
//
// The next filter in the notification chain should be called
//
SF_STATUS_REQ_NEXT_NOTIFICATION,
//
// This filter handled the notification. No other handles should be
// called for this particular notification type
//
SF_STATUS_REQ_HANDLED_NOTIFICATION,
//
// An error occurred. The server should use GetLastError() and indicate
// the error to the client
//
SF_STATUS_REQ_ERROR,
//
// The filter is an opaque stream filter and we're negotiating the
// session parameters. Only valid for raw read notification.
//
SF_STATUS_REQ_READ_NEXT
};
//
// pvNotification points to this structure for all request notification types
//
typedef struct _HTTP_FILTER_CONTEXT
{
DWORD cbSize;
//
// This is the structure revision level.
//
DWORD Revision;
//
// Private context information for the server.
//
PVOID ServerContext;
DWORD ulReserved;
//
// TRUE if this request is coming over a secure port
//
BOOL fIsSecurePort;
//
// A context that can be used by the filter
//
PVOID pFilterContext;
//
// Server callbacks
//
BOOL (WINAPI * GetServerVariable) (
struct _HTTP_FILTER_CONTEXT * pfc,
LPSTR lpszVariableName,
LPVOID lpvBuffer,
LPDWORD lpdwSize
);
BOOL (WINAPI * AddResponseHeaders) (
struct _HTTP_FILTER_CONTEXT * pfc,
LPSTR lpszHeaders,
DWORD dwReserved
);
BOOL (WINAPI * WriteClient) (
struct _HTTP_FILTER_CONTEXT * pfc,
LPVOID Buffer,
LPDWORD lpdwBytes,
DWORD dwReserved
);
VOID * (WINAPI * AllocMem) (
struct _HTTP_FILTER_CONTEXT * pfc,
DWORD cbSize,
DWORD dwReserved
);
BOOL (WINAPI * ServerSupportFunction) (
struct _HTTP_FILTER_CONTEXT * pfc,
enum SF_REQ_TYPE sfReq,
PVOID pData,
DWORD ul1,
DWORD ul2
);
} HTTP_FILTER_CONTEXT, *PHTTP_FILTER_CONTEXT;
//
// This structure is the notification info for the read and send raw data
// notification types
//
typedef struct _HTTP_FILTER_RAW_DATA
{
//
// This is a pointer to the data for the filter to process.
//
PVOID pvInData;
DWORD cbInData; // Number of valid data bytes
DWORD cbInBuffer; // Total size of buffer
DWORD dwReserved;
} HTTP_FILTER_RAW_DATA, *PHTTP_FILTER_RAW_DATA;
//
// This structure is the notification info for when the server is about to
// process the client headers
//
typedef struct _HTTP_FILTER_PREPROC_HEADERS
{
//
// Retrieves the specified header value. Header names should include
// the trailing ':'. The special values 'method', 'url' and 'version'
// can be used to retrieve the individual portions of the request line
//
BOOL (WINAPI * GetHeader) (
struct _HTTP_FILTER_CONTEXT * pfc,
LPSTR lpszName,
LPVOID lpvBuffer,
LPDWORD lpdwSize
);
//
// Replaces this header value to the specified value. To delete a header,
// specified a value of '\0'.
//
BOOL (WINAPI * SetHeader) (
struct _HTTP_FILTER_CONTEXT * pfc,
LPSTR lpszName,
LPSTR lpszValue
);
//
// Adds the specified header and value
//
BOOL (WINAPI * AddHeader) (
struct _HTTP_FILTER_CONTEXT * pfc,
LPSTR lpszName,
LPSTR lpszValue
);
DWORD dwReserved;
} HTTP_FILTER_PREPROC_HEADERS, *PHTTP_FILTER_PREPROC_HEADERS;
//
// Authentication information for this request.
//
typedef struct _HTTP_FILTER_AUTHENT
{
//
// Pointer to username and password, empty strings for the anonymous user
//
// Client's can overwrite these buffers which are guaranteed to be at
// least SF_MAX_USERNAME and SF_MAX_PASSWORD bytes large.
//
CHAR * pszUser;
DWORD cbUserBuff;
CHAR * pszPassword;
DWORD cbPasswordBuff;
} HTTP_FILTER_AUTHENT, *PHTTP_FILTER_AUTHENT;
//
// Indicates the server is going to use the specific physical mapping for
// the specified URL. Filters can modify the physical path in place.
//
typedef struct _HTTP_FILTER_URL_MAP
{
const CHAR * pszURL;
CHAR * pszPhysicalPath;
DWORD cbPathBuff;
} HTTP_FILTER_URL_MAP, *PHTTP_FILTER_URL_MAP;
//
// Bitfield indicating the requested resource has been denied by the server due
// to a logon failure, an ACL on a resource, an ISAPI Filter or an
// ISAPI Application/CGI Application.
//
// SF_DENIED_BY_CONFIG can appear with SF_DENIED_LOGON if the server
// configuration did not allow the user to logon.
//
#define SF_DENIED_LOGON 0x00000001
#define SF_DENIED_RESOURCE 0x00000002
#define SF_DENIED_FILTER 0x00000004
#define SF_DENIED_APPLICATION 0x00000008
#define SF_DENIED_BY_CONFIG 0x00010000
typedef struct _HTTP_FILTER_ACCESS_DENIED
{
const CHAR * pszURL; // Requesting URL
const CHAR * pszPhysicalPath; // Physical path of resource
DWORD dwReason; // Bitfield of SF_DENIED flags
} HTTP_FILTER_ACCESS_DENIED, *PHTTP_FILTER_ACCESS_DENIED;
//
// The log information about to be written to the server log file. The
// string pointers can be replaced but the memory must remain valid until
// the next notification
//
typedef struct _HTTP_FILTER_LOG
{
const CHAR * pszClientHostName;
const CHAR * pszClientUserName;
const CHAR * pszServerName;
const CHAR * pszOperation;
const CHAR * pszTarget;
const CHAR * pszParameters;
DWORD dwHttpStatus;
DWORD dwWin32Status;
} HTTP_FILTER_LOG, *PHTTP_FILTER_LOG;
//
// Notification Flags
//
// SF_NOTIFY_SECURE_PORT
// SF_NOTIFY_NONSECURE_PORT
//
// Indicates whether the application wants to be notified for transactions
// that are happenning on the server port(s) that support data encryption
// (such as PCT and SSL), on only the non-secure port(s) or both.
//
// SF_NOTIFY_READ_RAW_DATA
//
// Applications are notified after the server reads a block of memory
// from the client but before the server does any processing on the
// block. The data block may contain HTTP headers and entity data.
//
//
//
#define SF_NOTIFY_SECURE_PORT 0x00000001
#define SF_NOTIFY_NONSECURE_PORT 0x00000002
#define SF_NOTIFY_READ_RAW_DATA 0x00008000
#define SF_NOTIFY_PREPROC_HEADERS 0x00004000
#define SF_NOTIFY_AUTHENTICATION 0x00002000
#define SF_NOTIFY_URL_MAP 0x00001000
#define SF_NOTIFY_ACCESS_DENIED 0x00000800
#define SF_NOTIFY_SEND_RAW_DATA 0x00000400
#define SF_NOTIFY_LOG 0x00000200
#define SF_NOTIFY_END_OF_NET_SESSION 0x00000100
//
// Filter ordering flags
//
// Filters will tend to be notified by their specified
// ordering. For ties, notification order is determined by load order.
//
// SF_NOTIFY_ORDER_HIGH - Authentication or data transformation filters
// SF_NOTIFY_ORDER_MEDIUM
// SF_NOTIFY_ORDER_LOW - Logging filters that want the results of any other
// filters might specify this order.
//
#define SF_NOTIFY_ORDER_HIGH 0x00080000
#define SF_NOTIFY_ORDER_MEDIUM 0x00040000
#define SF_NOTIFY_ORDER_LOW 0x00020000
#define SF_NOTIFY_ORDER_DEFAULT SF_NOTIFY_ORDER_LOW
#define SF_NOTIFY_ORDER_MASK (SF_NOTIFY_ORDER_HIGH | \
SF_NOTIFY_ORDER_MEDIUM | \
SF_NOTIFY_ORDER_LOW)
//
// Filter version information, passed to GetFilterVersion
//
typedef struct _HTTP_FILTER_VERSION
{
//
// Version of the spec the server is using
//
DWORD dwServerFilterVersion;
//
// Fields specified by the client
//
DWORD dwFilterVersion;
CHAR lpszFilterDesc[SF_MAX_FILTER_DESC_LEN];
DWORD dwFlags;
} HTTP_FILTER_VERSION, *PHTTP_FILTER_VERSION;
//
// A filter DLL's entry point looks like this. The return code should be
// an SF_STATUS_TYPE
//
// NotificationType - Type of notification
// pvNotification - Pointer to notification specific data
//
DWORD
WINAPI
HttpFilterProc(
HTTP_FILTER_CONTEXT * pfc,
DWORD NotificationType,
VOID * pvNotification
);
BOOL
WINAPI
GetFilterVersion(
HTTP_FILTER_VERSION * pVer
);
#ifdef __cplusplus
}
#endif
#endif //_HTTPFILT_H_
