windows-nt/Source/XPSP1/NT/net/upnp/host/upnphost/udhhttp/callback.cpp
2020-09-26 16:20:57 +08:00

501 lines
16 KiB
C++

/*--
Copyright (c) 1995-1998 Microsoft Corporation
Module Name: filter.cpp
Author: John Spaith
Abstract: ISAPI Filter call back functions
--*/
// BUGBUG - don't support advanced header management on SF_NOTIFY_SEND_RESPONSE.
// IIS allows response headers to be deleted or set to different values after
// they are set with a call to SetHeader or AddHeader.
// Fix: None. This takes +300 lines of code, doesn't add much. Instead we
// dump all header data in a buffer.
#include "pch.h"
#pragma hdrstop
#include "httpd.h"
// Allocates and returns a buffer size cbSize. This will be deleted at the
// end of the session.
// The MSDN docs on this claim this returns a BOOL. Looking in httpfilt.h
// shows that the actual implementation is a VOID *.
VOID* WINAPI AllocMem(PHTTP_FILTER_CONTEXT pfc, DWORD cbSize, DWORD dwReserved)
{
CHECKPFC(pfc);
// NOTE: alloc mem isn't directly related to connection, don't check m_pFINfo->fAccept like
// the other filters do
return((CHttpRequest*)pfc->ServerContext)->m_pFInfo->AllocMem(cbSize,dwReserved);
}
VOID* CFilterInfo::AllocMem(DWORD cbSize, DWORD dwReserved)
{
if (cbSize == 0)
return NULL;
if (NULL == m_pAllocMem)
{
m_pAllocMem = MyRgAllocZ(PVOID,VALUE_GROW_SIZE);
if (! (m_pAllocMem))
{
TraceTag(ttidWebServer, "CFilterInfo::AllocMem failed on inital alloc, GLE=%d",GetLastError());
return NULL;
}
}
else if (m_nAllocBlocks % VALUE_GROW_SIZE == 0)
{
m_pAllocMem = MyRgReAlloc(PVOID,m_pAllocMem,m_nAllocBlocks,m_nAllocBlocks + VALUE_GROW_SIZE);
if ( !m_pAllocMem)
{
TraceTag(ttidWebServer, "CFilterInfo::AllocMem failed on re-allocing for block %d, GLE=%d",m_nAllocBlocks+1,GetLastError());
return NULL;
}
}
if (! (m_pAllocMem[m_nAllocBlocks] = MyRgAllocNZ(PVOID,cbSize)))
{
TraceTag(ttidWebServer, "CFilterInfo::AllocMem failed on allocating block %d, GLE=%d",m_nAllocBlocks+1,GetLastError());
return NULL;
}
m_nAllocBlocks++;
return m_pAllocMem[m_nAllocBlocks-1];
}
void CFilterInfo::FreeAllocMem()
{
DWORD dwI;
if (0 == m_nAllocBlocks || ! (m_pAllocMem))
return;
for (dwI = 0; dwI < m_nAllocBlocks; dwI++)
{
MyFree(m_pAllocMem[dwI]);
}
MyFree(m_pAllocMem);
}
// Adds httpd headers.
// In effect this is identical to a call to SetHeader or AddHeader except that
// the user formats the whole string (name and value) before caalling
// AddResponseHeaders, in Add/Set Header they come in 2 seperate fields.
BOOL WINAPI AddResponseHeaders(PHTTP_FILTER_CONTEXT pfc,LPSTR lpszHeaders,DWORD dwReserved)
{
CHECKPFC(pfc);
CHECKPTR(lpszHeaders);
CHECKFILTER(pfc);
if (dwReserved != 0)
{
SetLastError(ERROR_INVALID_PARAMETER);
return FALSE;
}
return((CHttpRequest*)pfc->ServerContext)->AddResponseHeaders(lpszHeaders,dwReserved);
}
BOOL CHttpRequest::AddResponseHeaders(LPSTR lpszHeaders,DWORD dwReserved)
{
// Can't set response headers on 0.9 version. Err code is like IIS.
if (m_dwVersion <= MAKELONG(9, 0))
{
SetLastError(ERROR_NOT_SUPPORTED);
return FALSE;
}
// According to MSDN, it's invalid to use this fcn during or after
// SEND_RESPONSE event. However, IIS doesn't report an error if
// this is called when it shouldn't be, so neither do we.
if ( m_pFInfo->m_dwSFEvent & (SF_NOTIFY_END_OF_NET_SESSION | SF_NOTIFY_END_OF_REQUEST |
SF_NOTIFY_LOG | SF_NOTIFY_SEND_RAW_DATA |
SF_NOTIFY_SEND_RESPONSE))
return TRUE;
// Note: We don't use CBuffer::AddHeaders because it does formatting, we assume
// here filter alreadf formatted everything correctly.
return m_bufRespHeaders.AppendData(lpszHeaders, strlen(lpszHeaders));
}
BOOL WINAPI GetServerVariable(PHTTP_FILTER_CONTEXT pfc, PSTR psz, PVOID pv, PDWORD pdw)
{
CHECKPFC(pfc);
CHECKPTRS3(psz, pv, pdw);
// We don't check m_fFAccept here because this function is read only,
// doesn't try and do anything across the network. Like IIS.
return((CHttpRequest*)pfc->ServerContext)->GetServerVariable(psz, pv, pdw, TRUE);
}
BOOL WINAPI WriteClient(PHTTP_FILTER_CONTEXT pfc, PVOID pv, PDWORD pdw, DWORD dwFlags)
{
CHECKPFC(pfc);
CHECKPTRS2(pv, pdw);
// CHECKFILTER(pfc); // IIS always accepts WriteClient, even if filter has returned an error at some point.
if (dwFlags != 0)
{
SetLastError(ERROR_INVALID_PARAMETER);
return FALSE;
}
return((CHttpRequest*)pfc->ServerContext)->WriteClient(pv,pdw,TRUE);
}
// Misc Server features. See MSDN for full docs.
BOOL WINAPI ServerSupportFunction(PHTTP_FILTER_CONTEXT pfc, enum SF_REQ_TYPE sfReq,
PVOID pData, ULONG_PTR ul1, ULONG_PTR ul2)
{
CHECKPFC(pfc);
CHECKFILTER(pfc);
return((CHttpRequest*)pfc->ServerContext)->ServerSupportFunction(sfReq, pData, ul1, ul2);
}
BOOL CHttpRequest::ServerSupportFunction(enum SF_REQ_TYPE sfReq,PVOID pData,
ULONG_PTR ul1, ULONG_PTR ul2)
{
switch (sfReq)
{
case SF_REQ_ADD_HEADERS_ON_DENIAL:
{
return MyStrCatA(&m_pFInfo->m_pszDenyHeader,(PSTR) pData);
}
case SF_REQ_DISABLE_NOTIFICATIONS:
{
// u11 has data as to which flags to deactivate for this session,
// For example, setting u11 = SF_NOTIFY_SEND_RAW_DATA | SF_NOTIFY_LOG
// would disable notifications to the filter that called this fcn for
// those events on this request only (per request, not per session!).
// These values are reset to 1's at the end of each request in CHttpRequest::ReInit
m_pFInfo->m_pdwEnable[m_pFInfo->m_iFIndex] &= (m_pFInfo->m_pdwEnable[m_pFInfo->m_iFIndex] ^ ul1);
return TRUE;
}
case SF_REQ_SEND_RESPONSE_HEADER:
{
// no Connection header...let ISAPI send one if it wants
CHttpResponse resp(m_socket, STATUS_OK, CONN_CLOSE,this);
m_rs = STATUS_OK;
// no body, default or otherwise (leave that to the ISAPI), but add default headers
resp.SendResponse((PSTR) ul1, (PSTR) pData, TRUE);
// The reasons for doing this are documented in FilterNoResponse()
// Note: We don't check this sent headers here because IIS doesn't,
// so it's possible to make multiple calls with this option even though it
// doesn't make that much sense for a filter to do so.
m_pFInfo->m_fSentHeaders = TRUE;
m_fKeepAlive = FALSE;
return TRUE;
}
case SF_REQ_SET_NEXT_READ_SIZE:
{
m_pFInfo->m_dwNextReadSize = (DWORD)ul1;
return TRUE;
}
// BUGBUG -- unsupported flags.
// case SF_REQ_NORMALIZE_URL: // TBD
// case SF_REQ_GET_CONNID: // IIS doesn't support in versions 4+
// case SF_REQ_GET_PROPERTY: // Relates to meta database IIS uses but we don't
// case SF_REQ_SET_PROXY_INFO: // No proxy stuff in CE
default:
{
TraceTag(ttidWebServer, "Unsupported or invald ServerSupportFcn request = 0x%08x",sfReq);
SetLastError(ERROR_INVALID_PARAMETER);
return FALSE;
}
}
return TRUE;
}
//***************************************************************************
// Extended filter header options
//
// These fcns allow the filter to perform more advanced header fncs automatically,
// On PREPROC_HEADERS event, it's possible for the filter to change CHttpRequest
// state information through the SetHeaders and AddHeaders callback. We support
// changing URL, Version, If-modified-since, and method through the preproc
// headers calls.
// In a SEND_RESPONSE event, it's possible for the filter to modify the response
// headers through SetHEaders or AddHeaders.
// Unlike IIS, we don't allow the filter to delete a header once it's set, or
// to overwrite a header's information with new info. We only allow the header
// data to be appended to.
//***************************************************************************
BOOL WINAPI GetHeader(PHTTP_FILTER_CONTEXT pfc, LPSTR lpszName, LPVOID lpvBuffer, LPDWORD lpdwSize)
{
CHECKPFC(pfc);
CHECKPTRS3(lpszName, lpvBuffer, lpdwSize);
CHECKFILTER(pfc);
return((CHttpRequest*)pfc->ServerContext)->GetHeader(lpszName, lpvBuffer, lpdwSize);
}
BOOL WINAPI SetHeader(PHTTP_FILTER_CONTEXT pfc, LPSTR lpszName, LPSTR lpszValue)
{
CHECKPFC(pfc);
CHECKPTRS2(lpszName, lpszValue);
CHECKFILTER(pfc);
return((CHttpRequest*)pfc->ServerContext)->SetHeader(lpszName, lpszValue);
}
// Retrieves raw header value for specified name.
BOOL CHttpRequest::GetHeader(LPSTR lpszName, LPVOID lpvBuffer, LPDWORD lpdwSize)
{
DEBUG_CODE_INIT;
BOOL ret = FALSE;
DWORD cbSizeNeeded;
char szBuf[MAXHEADERS];
PSTR pszRet = (PSTR)-1;
PSTR pszTrav = NULL;
PSTR pszEndOfHeaders = NULL;
DWORD cbName;
// this is the only event we allow this for. This is like IIS, but not docced in MSDN.
if (m_pFInfo->m_dwSFEvent != SF_NOTIFY_PREPROC_HEADERS)
{
SetLastError(ERROR_INVALID_INDEX);
myleave(1405);
}
// For method, url, and version (from simple request line) we get the data
// from CHttpRequest
if (0==_stricmp(lpszName, "version"))
{
// There's no sprintf in older versions of CE.
// sprintf(szBuf, "HTTP/%d.%d", HIWORD(m_dwVersion), LOWORD(m_dwVersion));
WriteHTTPVersion(szBuf,m_dwVersion);
pszRet = szBuf;
}
else if (0 == _stricmp(lpszName, "url"))
pszRet = m_pszURL;
else if (0 == _stricmp(lpszName, "method"))
pszRet = m_pszMethod;
else
{
// if it's not one of the 3 special values, we search through the raw
// buffer for the header name.
pszTrav = (PSTR) m_bufRequest.Headers();
pszTrav = strstr(pszTrav,cszCRLF); // skip past simple http header
pszEndOfHeaders = pszTrav + m_bufRequest.GetINextOut();
cbName = strlen(lpszName);
for (; pszTrav; pszTrav = strstr(pszTrav,cszCRLF))
{
pszTrav += sizeof("\r\n") - 1;
// reached end of headers, double CRLF
if (*pszTrav == '\r')
break;
// Make sure we don't walk off the end of the buffer.
if ((int) cbName > (pszEndOfHeaders - pszTrav))
break;
if (0 == _memicmp(pszTrav,lpszName,cbName))
{
pszTrav += cbName;
if (' ' == *pszTrav) // must be a space next for a match
{
pszRet = pszTrav + 1;
pszTrav = strstr(pszTrav,cszCRLF);
DEBUGCHK(pszTrav != NULL); // should catch improperly formatted headers in parser
*pszTrav = 0; // make this the end of string temporarily
break;
}
}
}
}
if ((PSTR)(-1) == pszRet)
{
// unknown var
SetLastError(ERROR_INVALID_INDEX);
myleave(1400);
}
if ((cbSizeNeeded = strlen(pszRet)+1) > *lpdwSize)
{
*lpdwSize = cbSizeNeeded;
SetLastError(ERROR_INSUFFICIENT_BUFFER);
myleave(1401);
}
memcpy(lpvBuffer, pszRet, cbSizeNeeded);
ret = TRUE;
done:
TraceTag(ttidWebServer, "HTTPD:GetHeader failed with variable name<<%s>>,err = %d ",lpszName,err);
if (pszTrav)
*pszTrav = '\r'; // reset the value
return ret;
}
// BUGBUG: SetHeader and AddHeader both use SetHeader fcn, breaks IIS spec.
// Fix: None. On IIS for a PREPROC_HEADER event, filter can call (for instance)
// an AddHeader("URL","url.htm"), which will append to the end of the existing URL.
// In this case, if the requested URL was "foo.htm", IIS would lookup foo.htm,url.htm
// This isn't worth the hassle (the code to do it is below, though).
BOOL CHttpRequest::SetHeader(LPSTR lpszName, LPSTR lpszValue)
{
DEBUG_CODE_INIT;
PSTR pszNew = NULL;
BOOL ret = FALSE;
TraceTag(ttidWebServer, "Servicing SetHeader request with name<<%s>>,value<<%s>> ",lpszName,lpszValue);
if (0==_stricmp(lpszName, "version"))
{
SetHTTPVersion(lpszValue,&m_dwVersion);
ret = TRUE;
}
else if (0 == _stricmp(lpszName, "url"))
{
pszNew = MySzDupA(lpszValue);
if (!pszNew)
myleave(256);
MyFree(m_pszURL);
m_pszURL = pszNew;
ret = TRUE;
}
else if (0 == _stricmp(lpszName, "method"))
{
pszNew = MySzDupA(lpszValue);
if (!pszNew)
myleave(257);
MyFree(m_pszMethod);
m_pszMethod = pszNew;
ret = TRUE;
}
// BUGBUG - changing headers on the preproc event would require advanced
// header management.
// Fix: None. If the filter writer wants to change the state that headers
// set they'll have plenty of oppurtunity to do it in later events.
else if (m_pFInfo->m_dwSFEvent == SF_NOTIFY_PREPROC_HEADERS)
{
myretleave(TRUE,0);
}
else // custom response header, like "Content-length:" or whatever else
{
// Can't set response headers on 0.9 version. Err code is like IIS.
if (m_dwVersion <= MAKELONG(9, 0))
{
SetLastError(ERROR_NOT_SUPPORTED);
myleave(258);
}
ret = m_bufRespHeaders.AddHeader(lpszName,lpszValue);
}
done:
TraceTag(ttidWebServer, "SetHeader failed with request with name<<%s>>,value<<%s>>, GLE=%d ",lpszName,lpszValue,GetLastError());
return ret;
}
// This handles a special case for Filters / extensions. IF a call is made
// to ISAPI Extension ServerSupportFunction with HSE_REQ_MAP_URL_TO_PATH, then
// a filter call to SF_NOTIFY_URL_MAP is performed.
// We can't call the filter directly because SF_NOTIFY_URL_MAP usually gets
// path info from the CHttpRequest class, but in this case it's getting it's
// data from and writing out to a user buffer.
// pszBuf is the original string passed into ServerSupportFunction by the ISAPI.
// When the function begins it has a virtual path, on successful termination it has a physical path
// pdwSize is it's size
// wszPath is it's mapped virtual root path
// dwBufNeeded is the size of the buffer required to the physical path.
BOOL CHttpRequest::FilterMapURL(PSTR pszBuf, WCHAR *wszPath, DWORD *pdwSize, DWORD dwBufNeeded, PSTR pszURLEx)
{
DEBUG_CODE_INIT;
PSTR pszPhysicalOrg;
PSTR pszPhysicalNew;
PSTR pszVirtual = pszURLEx ? pszURLEx : pszBuf;
DWORD cbBufNew = dwBufNeeded;
BOOL ret = FALSE;
// Regardless of if buffer was big enough to hold the original data, we always
// allocate a buf for the filter. The filter may end up changing the data
// so it's small enough to fit in the buffer.
// Don't use MySzDupWtoA here because we alread know the length needed, MySzDupWtoA
// would needlessly recompute it.
if (NULL == (pszPhysicalOrg = MyRgAllocNZ(CHAR,dwBufNeeded)))
myleave(710);
MyW2A(wszPath, pszPhysicalOrg, dwBufNeeded);
pszPhysicalNew = pszPhysicalOrg; // Keep a copy of pointer for freeing, CallFilter may modify it
if ( !CallFilter(SF_NOTIFY_URL_MAP,&pszVirtual,(int*) &cbBufNew,&pszPhysicalNew))
myleave(711);
// Buffer isn't big enough
if (*pdwSize < cbBufNew)
{
SetLastError(ERROR_INSUFFICIENT_BUFFER);
myleave(712);
}
// Copy changes over. pszPhysicalNew will be filter set or will be
// the original wszPath converted to ASCII without filter.
if (NULL != pszPhysicalNew)
{
memcpy(pszBuf,pszPhysicalNew,cbBufNew);
}
ret = TRUE;
done:
TraceTag(ttidWebServer, "FilterMapURL failed, err = %d, GLE=%X",err,GetLastError());
*pdwSize = cbBufNew;
MyFree(pszPhysicalOrg);
return ret;
}