reactos/subsystems/csr/csrsrv/api.c
Hermès Bélusca-Maïto d2aeaba5f8
[CSR][NTDLL] Move the CSR subsystem into its own "csr" sub-directory. (#4802)
Move CSRSS, CSRSRV there, as well as CSR client calls from NTDLL into a "CSRLIB" library.
2022-10-29 17:17:29 +02:00

1533 lines
50 KiB
C

/*
* COPYRIGHT: See COPYING in the top level directory
* PROJECT: ReactOS Client/Server Runtime SubSystem
* FILE: subsystems/win32/csrsrv/api.c
* PURPOSE: CSR Server DLL API LPC Implementation
* "\Windows\ApiPort" port process management functions
* PROGRAMMERS: Alex Ionescu (alex@relsoft.net)
*/
/* INCLUDES *******************************************************************/
#include "srv.h"
#include <ndk/kefuncs.h>
#define NDEBUG
#include <debug.h>
/* GLOBALS ********************************************************************/
BOOLEAN (*CsrClientThreadSetup)(VOID) = NULL;
UNICODE_STRING CsrApiPortName;
volatile ULONG CsrpStaticThreadCount;
volatile ULONG CsrpDynamicThreadTotal;
extern ULONG CsrMaxApiRequestThreads;
/* FUNCTIONS ******************************************************************/
/*++
* @name CsrCallServerFromServer
* @implemented NT4
*
* The CsrCallServerFromServer routine calls a CSR API from within a server.
* It avoids using LPC messages since the request isn't coming from a client.
*
* @param ReceiveMsg
* Pointer to the CSR API Message to send to the server.
*
* @param ReplyMsg
* Pointer to the CSR API Message to receive from the server.
*
* @return STATUS_SUCCESS in case of success, STATUS_ILLEGAL_FUNCTION
* if the ApiNumber is invalid, or STATUS_ACCESS_VIOLATION if there
* was a problem executing the API.
*
* @remarks None.
*
*--*/
NTSTATUS
NTAPI
CsrCallServerFromServer(IN PCSR_API_MESSAGE ReceiveMsg,
IN OUT PCSR_API_MESSAGE ReplyMsg)
{
ULONG ServerId;
PCSR_SERVER_DLL ServerDll = NULL;
ULONG ApiId;
CSR_REPLY_CODE ReplyCode = CsrReplyImmediately;
/* Get the Server ID */
ServerId = CSR_API_NUMBER_TO_SERVER_ID(ReceiveMsg->ApiNumber);
/* Make sure that the ID is within limits, and the Server DLL loaded */
if ((ServerId >= CSR_SERVER_DLL_MAX) ||
(!(ServerDll = CsrLoadedServerDll[ServerId])))
{
/* We are beyond the Maximum Server ID */
#ifdef CSR_DBG
DPRINT1("CSRSS: %lx is invalid ServerDllIndex (%08x)\n",
ServerId, ServerDll);
if (NtCurrentPeb()->BeingDebugged) DbgBreakPoint();
#endif
ReplyMsg->Status = STATUS_ILLEGAL_FUNCTION;
return STATUS_ILLEGAL_FUNCTION;
}
else
{
/* Get the API ID, normalized with our Base ID */
ApiId = CSR_API_NUMBER_TO_API_ID(ReceiveMsg->ApiNumber) - ServerDll->ApiBase;
/* Make sure that the ID is within limits, and the entry exists */
if ((ApiId >= ServerDll->HighestApiSupported) ||
((ServerDll->ValidTable) && !(ServerDll->ValidTable[ApiId])))
{
/* We are beyond the Maximum API ID, or it doesn't exist */
#ifdef CSR_DBG
DPRINT1("API: %d\n", ApiId);
DPRINT1("CSRSS: %lx (%s) is invalid ApiTableIndex for %Z or is an "
"invalid API to call from the server.\n",
ApiId,
((ServerDll->NameTable) && (ServerDll->NameTable[ApiId])) ?
ServerDll->NameTable[ApiId] : "*** UNKNOWN ***",
&ServerDll->Name);
if (NtCurrentPeb()->BeingDebugged) DbgBreakPoint();
#endif
ReplyMsg->Status = STATUS_ILLEGAL_FUNCTION;
return STATUS_ILLEGAL_FUNCTION;
}
}
#ifdef CSR_DBG
if (CsrDebug & 2)
{
DPRINT1("CSRSS: %s Api Request received from server process\n",
ServerDll->NameTable[ApiId]);
}
#endif
/* Validation complete, start SEH */
_SEH2_TRY
{
/* Call the API, get the reply code and return the result */
ReplyMsg->Status = ServerDll->DispatchTable[ApiId](ReceiveMsg, &ReplyCode);
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
/* If we got an exception, return access violation */
ReplyMsg->Status = STATUS_ACCESS_VIOLATION;
}
_SEH2_END;
/* Return success */
return STATUS_SUCCESS;
}
/*++
* @name CsrApiHandleConnectionRequest
*
* The CsrApiHandleConnectionRequest routine handles and accepts a new
* connection request to the CSR API LPC Port.
*
* @param ApiMessage
* Pointer to the incoming CSR API Message which contains the
* connection request.
*
* @return STATUS_SUCCESS in case of success, or status code which caused
* the routine to error.
*
* @remarks This routine is responsible for attaching the Shared Section to
* new clients connecting to CSR.
*
*--*/
NTSTATUS
NTAPI
CsrApiHandleConnectionRequest(IN PCSR_API_MESSAGE ApiMessage)
{
PCSR_THREAD CsrThread = NULL;
PCSR_PROCESS CsrProcess = NULL;
NTSTATUS Status = STATUS_SUCCESS;
PCSR_API_CONNECTINFO ConnectInfo = &ApiMessage->ConnectionInfo;
BOOLEAN AllowConnection = FALSE;
REMOTE_PORT_VIEW RemotePortView;
HANDLE ServerPort;
/* Acquire the Process Lock */
CsrAcquireProcessLock();
/* Lookup the CSR Thread */
CsrThread = CsrLocateThreadByClientId(NULL, &ApiMessage->Header.ClientId);
/* Check if we have a thread */
if (CsrThread)
{
/* Get the Process and make sure we have it as well */
CsrProcess = CsrThread->Process;
if (CsrProcess)
{
/* Reference the Process */
CsrLockedReferenceProcess(CsrProcess);
/* Attach the Shared Section */
Status = CsrSrvAttachSharedSection(CsrProcess, ConnectInfo);
if (NT_SUCCESS(Status))
{
/* Allow the connection and return debugging flag */
ConnectInfo->DebugFlags = CsrDebug;
AllowConnection = TRUE;
}
/* Dereference the Process */
CsrLockedDereferenceProcess(CsrProcess);
}
}
/* Release the Process Lock */
CsrReleaseProcessLock();
/* Setup the Port View Structure */
RemotePortView.Length = sizeof(REMOTE_PORT_VIEW);
RemotePortView.ViewSize = 0;
RemotePortView.ViewBase = NULL;
/* Save the Process ID */
ConnectInfo->ServerProcessId = NtCurrentTeb()->ClientId.UniqueProcess;
/* Accept the Connection */
ASSERT(!AllowConnection || CsrProcess);
Status = NtAcceptConnectPort(&ServerPort,
AllowConnection ? UlongToPtr(CsrProcess->SequenceNumber) : 0,
&ApiMessage->Header,
AllowConnection,
NULL,
&RemotePortView);
if (!NT_SUCCESS(Status))
{
DPRINT1("CSRSS: NtAcceptConnectPort - failed. Status == %X\n", Status);
}
else if (AllowConnection)
{
if (CsrDebug & 2)
{
DPRINT1("CSRSS: ClientId: %lx.%lx has ClientView: Base=%p, Size=%lx\n",
ApiMessage->Header.ClientId.UniqueProcess,
ApiMessage->Header.ClientId.UniqueThread,
RemotePortView.ViewBase,
RemotePortView.ViewSize);
}
/* Set some Port Data in the Process */
CsrProcess->ClientPort = ServerPort;
CsrProcess->ClientViewBase = (ULONG_PTR)RemotePortView.ViewBase;
CsrProcess->ClientViewBounds = (ULONG_PTR)((ULONG_PTR)RemotePortView.ViewBase +
(ULONG_PTR)RemotePortView.ViewSize);
/* Complete the connection */
Status = NtCompleteConnectPort(ServerPort);
if (!NT_SUCCESS(Status))
{
DPRINT1("CSRSS: NtCompleteConnectPort - failed. Status == %X\n", Status);
}
}
else
{
DPRINT1("CSRSS: Rejecting Connection Request from ClientId: %lx.%lx\n",
ApiMessage->Header.ClientId.UniqueProcess,
ApiMessage->Header.ClientId.UniqueThread);
}
/* Return status to caller */
return Status;
}
/*++
* @name CsrpCheckRequestThreads
*
* The CsrpCheckRequestThreads routine checks if there are no more threads
* to handle CSR API Requests, and creates a new thread if possible, to
* avoid starvation.
*
* @param None.
*
* @return STATUS_SUCCESS in case of success, STATUS_UNSUCCESSFUL
* if a new thread couldn't be created.
*
* @remarks None.
*
*--*/
NTSTATUS
NTAPI
CsrpCheckRequestThreads(VOID)
{
HANDLE hThread;
CLIENT_ID ClientId;
NTSTATUS Status;
/* Decrease the count, and see if we're out */
if (InterlockedDecrementUL(&CsrpStaticThreadCount) == 0)
{
/* Check if we've still got space for a Dynamic Thread */
if (CsrpDynamicThreadTotal < CsrMaxApiRequestThreads)
{
/* Create a new dynamic thread */
Status = RtlCreateUserThread(NtCurrentProcess(),
NULL,
TRUE,
0,
0,
0,
(PVOID)CsrApiRequestThread,
NULL,
&hThread,
&ClientId);
/* Check success */
if (NT_SUCCESS(Status))
{
/* Increase the thread counts */
InterlockedIncrementUL(&CsrpStaticThreadCount);
InterlockedIncrementUL(&CsrpDynamicThreadTotal);
/* Add a new server thread */
if (CsrAddStaticServerThread(hThread,
&ClientId,
CsrThreadIsServerThread))
{
/* Activate it */
NtResumeThread(hThread, NULL);
}
else
{
/* Failed to create a new static thread */
InterlockedDecrementUL(&CsrpStaticThreadCount);
InterlockedDecrementUL(&CsrpDynamicThreadTotal);
/* Terminate it */
DPRINT1("Failing\n");
NtTerminateThread(hThread, 0);
NtClose(hThread);
/* Return */
return STATUS_UNSUCCESSFUL;
}
}
}
}
/* Success */
return STATUS_SUCCESS;
}
/*++
* @name CsrApiRequestThread
*
* The CsrApiRequestThread routine handles incoming messages or connection
* requests on the CSR API LPC Port.
*
* @param Parameter
* System-default user-defined parameter. Unused.
*
* @return The thread exit code, if the thread is terminated.
*
* @remarks Before listening on the port, the routine will first attempt
* to connect to the user subsystem.
*
*--*/
NTSTATUS
NTAPI
CsrApiRequestThread(IN PVOID Parameter)
{
PTEB Teb = NtCurrentTeb();
LARGE_INTEGER TimeOut;
PCSR_THREAD CurrentThread, CsrThread;
NTSTATUS Status;
CSR_REPLY_CODE ReplyCode;
PCSR_API_MESSAGE ReplyMsg;
CSR_API_MESSAGE ReceiveMsg;
PCSR_PROCESS CsrProcess;
PHARDERROR_MSG HardErrorMsg;
PVOID PortContext;
PCSR_SERVER_DLL ServerDll;
PCLIENT_DIED_MSG ClientDiedMsg;
PDBGKM_MSG DebugMessage;
ULONG ServerId, ApiId, MessageType, i;
HANDLE ReplyPort;
/* Setup LPC loop port and message */
ReplyMsg = NULL;
ReplyPort = CsrApiPort;
/* Connect to user32 */
while (!CsrConnectToUser())
{
/* Set up the timeout for the connect (30 seconds) */
TimeOut.QuadPart = -30 * 1000 * 1000 * 10;
/* Keep trying until we get a response */
Teb->Win32ClientInfo[0] = 0;
NtDelayExecution(FALSE, &TimeOut);
}
/* Get our thread */
CurrentThread = Teb->CsrClientThread;
/* If we got an event... */
if (Parameter)
{
/* Set it, to let stuff waiting on us load */
Status = NtSetEvent((HANDLE)Parameter, NULL);
ASSERT(NT_SUCCESS(Status));
/* Increase the Thread Counts */
InterlockedIncrementUL(&CsrpStaticThreadCount);
InterlockedIncrementUL(&CsrpDynamicThreadTotal);
}
/* Now start the loop */
while (TRUE)
{
/* Make sure the real CID is set */
Teb->RealClientId = Teb->ClientId;
#ifdef CSR_DBG
/* Debug check */
if (Teb->CountOfOwnedCriticalSections)
{
DPRINT1("CSRSRV: FATAL ERROR. CsrThread is Idle while holding %lu critical sections\n",
Teb->CountOfOwnedCriticalSections);
DPRINT1("CSRSRV: Last Receive Message %lx ReplyMessage %lx\n",
&ReceiveMsg, ReplyMsg);
DbgBreakPoint();
}
#endif
/* Wait for a message to come through */
Status = NtReplyWaitReceivePort(ReplyPort,
&PortContext,
&ReplyMsg->Header,
&ReceiveMsg.Header);
/* Check if we didn't get success */
if (Status != STATUS_SUCCESS)
{
/* Was it a failure or another success code? */
if (!NT_SUCCESS(Status))
{
#ifdef CSR_DBG
/* Check for specific status cases */
if ((Status != STATUS_INVALID_CID) &&
(Status != STATUS_UNSUCCESSFUL) &&
((Status != STATUS_INVALID_HANDLE) || (ReplyPort == CsrApiPort)))
{
/* Notify the debugger */
DPRINT1("CSRSS: ReceivePort failed - Status == %X\n", Status);
DPRINT1("CSRSS: ReplyPortHandle %lx CsrApiPort %lx\n", ReplyPort, CsrApiPort);
}
#endif
/* We failed big time, so start out fresh */
ReplyMsg = NULL;
ReplyPort = CsrApiPort;
continue;
}
else
{
/* A strange "success" code, just try again */
DPRINT1("NtReplyWaitReceivePort returned \"success\" status 0x%x\n", Status);
continue;
}
}
// ASSERT(ReceiveMsg.Header.u1.s1.TotalLength >= sizeof(PORT_MESSAGE));
// ASSERT(ReceiveMsg.Header.u1.s1.TotalLength < sizeof(ReceiveMsg));
/* Use whatever Client ID we got */
Teb->RealClientId = ReceiveMsg.Header.ClientId;
/* Get the Message Type */
MessageType = ReceiveMsg.Header.u2.s2.Type;
/* Handle connection requests */
if (MessageType == LPC_CONNECTION_REQUEST)
{
/* Handle the Connection Request */
CsrApiHandleConnectionRequest(&ReceiveMsg);
ReplyMsg = NULL;
ReplyPort = CsrApiPort;
continue;
}
/* It's some other kind of request. Get the lock for the lookup */
CsrAcquireProcessLock();
/* Now do the lookup to get the CSR_THREAD */
CsrThread = CsrLocateThreadByClientId(&CsrProcess,
&ReceiveMsg.Header.ClientId);
/* Did we find a thread? */
if (!CsrThread)
{
/* This wasn't a CSR Thread, release lock */
CsrReleaseProcessLock();
/* If this was an exception, handle it */
if (MessageType == LPC_EXCEPTION)
{
ReplyMsg = &ReceiveMsg;
ReplyPort = CsrApiPort;
ReplyMsg->Status = DBG_CONTINUE;
}
else if (MessageType == LPC_PORT_CLOSED ||
MessageType == LPC_CLIENT_DIED)
{
/* The Client or Port are gone, loop again */
ReplyMsg = NULL;
ReplyPort = CsrApiPort;
}
else if (MessageType == LPC_ERROR_EVENT)
{
/* If it's a hard error, handle this too */
HardErrorMsg = (PHARDERROR_MSG)&ReceiveMsg;
/* Default it to unhandled */
HardErrorMsg->Response = ResponseNotHandled;
/* Check if there are free api threads */
CsrpCheckRequestThreads();
if (CsrpStaticThreadCount)
{
/* Loop every Server DLL */
for (i = 0; i < CSR_SERVER_DLL_MAX; i++)
{
/* Get the Server DLL */
ServerDll = CsrLoadedServerDll[i];
/* Check if it's valid and if it has a Hard Error Callback */
if ((ServerDll) && (ServerDll->HardErrorCallback))
{
/* Call it */
ServerDll->HardErrorCallback(NULL /* == CsrThread */, HardErrorMsg);
/* If it's handled, get out of here */
if (HardErrorMsg->Response != ResponseNotHandled) break;
}
}
}
/* Increase the thread count */
InterlockedIncrementUL(&CsrpStaticThreadCount);
/* If the response was 0xFFFFFFFF, we'll ignore it */
if (HardErrorMsg->Response == 0xFFFFFFFF)
{
ReplyMsg = NULL;
ReplyPort = CsrApiPort;
}
else
{
ReplyMsg = &ReceiveMsg;
ReplyPort = CsrApiPort;
}
}
else if (MessageType == LPC_REQUEST)
{
/* This is an API Message coming from a non-CSR Thread */
ReplyMsg = &ReceiveMsg;
ReplyPort = CsrApiPort;
ReplyMsg->Status = STATUS_ILLEGAL_FUNCTION;
}
else if (MessageType == LPC_DATAGRAM)
{
/* This is an API call, get the Server ID */
ServerId = CSR_API_NUMBER_TO_SERVER_ID(ReceiveMsg.ApiNumber);
/* Make sure that the ID is within limits, and the Server DLL loaded */
ServerDll = NULL;
if ((ServerId >= CSR_SERVER_DLL_MAX) ||
(!(ServerDll = CsrLoadedServerDll[ServerId])))
{
/* We are beyond the Maximum Server ID */
#ifdef CSR_DBG
DPRINT1("CSRSS: %lx is invalid ServerDllIndex (%08x)\n",
ServerId, ServerDll);
if (NtCurrentPeb()->BeingDebugged) DbgBreakPoint();
#endif
ReplyMsg = NULL;
ReplyPort = CsrApiPort;
continue;
}
/* Get the API ID, normalized with our Base ID */
ApiId = CSR_API_NUMBER_TO_API_ID(ReceiveMsg.ApiNumber) - ServerDll->ApiBase;
/* Make sure that the ID is within limits, and the entry exists */
if (ApiId >= ServerDll->HighestApiSupported)
{
/* We are beyond the Maximum API ID, or it doesn't exist */
#ifdef CSR_DBG
DPRINT1("CSRSS: %lx is invalid ApiTableIndex for %Z\n",
CSR_API_NUMBER_TO_API_ID(ReceiveMsg.ApiNumber),
&ServerDll->Name);
#endif
ReplyPort = CsrApiPort;
ReplyMsg = NULL;
continue;
}
#ifdef CSR_DBG
if (CsrDebug & 2)
{
DPRINT1("[%02x] CSRSS: [%02x,%02x] - %s Api called from %08x\n",
Teb->ClientId.UniqueThread,
ReceiveMsg.Header.ClientId.UniqueProcess,
ReceiveMsg.Header.ClientId.UniqueThread,
ServerDll->NameTable[ApiId],
NULL);
}
#endif
/* Assume success */
ReceiveMsg.Status = STATUS_SUCCESS;
/* Validation complete, start SEH */
_SEH2_TRY
{
/* Make sure we have enough threads */
CsrpCheckRequestThreads();
/* Call the API and get the reply code */
ReplyMsg = NULL;
ReplyPort = CsrApiPort;
ServerDll->DispatchTable[ApiId](&ReceiveMsg, &ReplyCode);
/* Increase the static thread count */
InterlockedIncrementUL(&CsrpStaticThreadCount);
}
_SEH2_EXCEPT(CsrUnhandledExceptionFilter(_SEH2_GetExceptionInformation()))
{
ReplyMsg = NULL;
ReplyPort = CsrApiPort;
}
_SEH2_END;
}
else
{
/* Some other ignored message type */
ReplyMsg = NULL;
ReplyPort = CsrApiPort;
}
/* Keep going */
continue;
}
/* We have a valid thread, was this an LPC Request? */
if (MessageType != LPC_REQUEST)
{
/* It's not an API, check if the client died */
if (MessageType == LPC_CLIENT_DIED)
{
/* Get the information and check if it matches our thread */
ClientDiedMsg = (PCLIENT_DIED_MSG)&ReceiveMsg;
if (ClientDiedMsg->CreateTime.QuadPart == CsrThread->CreateTime.QuadPart)
{
/* Now we reply to the dying client */
ReplyPort = CsrThread->Process->ClientPort;
/* Reference the thread */
CsrLockedReferenceThread(CsrThread);
/* Destroy the thread in the API Message */
CsrDestroyThread(&ReceiveMsg.Header.ClientId);
/* Check if the thread was actually ourselves */
if (CsrProcess->ThreadCount == 1)
{
/* Kill the process manually here */
CsrDestroyProcess(&CsrThread->ClientId, 0);
}
/* Remove our extra reference */
CsrLockedDereferenceThread(CsrThread);
}
/* Release the lock and keep looping */
CsrReleaseProcessLock();
ReplyMsg = NULL;
ReplyPort = CsrApiPort;
continue;
}
/* Reference the thread and release the lock */
CsrLockedReferenceThread(CsrThread);
CsrReleaseProcessLock();
/* Check if this was an exception */
if (MessageType == LPC_EXCEPTION)
{
/* Kill the process */
NtTerminateProcess(CsrProcess->ProcessHandle, STATUS_ABANDONED);
/* Destroy it from CSR */
CsrDestroyProcess(&ReceiveMsg.Header.ClientId, STATUS_ABANDONED);
/* Return a Debug Message */
DebugMessage = (PDBGKM_MSG)&ReceiveMsg;
DebugMessage->ReturnedStatus = DBG_CONTINUE;
ReplyMsg = &ReceiveMsg;
ReplyPort = CsrApiPort;
/* Remove our extra reference */
CsrDereferenceThread(CsrThread);
}
else if (MessageType == LPC_ERROR_EVENT)
{
/* If it's a hard error, handle this too */
HardErrorMsg = (PHARDERROR_MSG)&ReceiveMsg;
/* Default it to unhandled */
HardErrorMsg->Response = ResponseNotHandled;
/* Check if there are free api threads */
CsrpCheckRequestThreads();
if (CsrpStaticThreadCount)
{
/* Loop every Server DLL */
for (i = 0; i < CSR_SERVER_DLL_MAX; i++)
{
/* Get the Server DLL */
ServerDll = CsrLoadedServerDll[i];
/* Check if it's valid and if it has a Hard Error Callback */
if ((ServerDll) && (ServerDll->HardErrorCallback))
{
/* Call it */
ServerDll->HardErrorCallback(CsrThread, HardErrorMsg);
/* If it's handled, get out of here */
if (HardErrorMsg->Response != ResponseNotHandled) break;
}
}
}
/* Increase the thread count */
InterlockedIncrementUL(&CsrpStaticThreadCount);
/* If the response was 0xFFFFFFFF, we'll ignore it */
if (HardErrorMsg->Response == 0xFFFFFFFF)
{
ReplyMsg = NULL;
ReplyPort = CsrApiPort;
}
else
{
CsrDereferenceThread(CsrThread);
ReplyMsg = &ReceiveMsg;
ReplyPort = CsrApiPort;
}
}
else
{
/* Something else */
CsrDereferenceThread(CsrThread);
ReplyMsg = NULL;
}
/* Keep looping */
continue;
}
/* We got an API Request */
CsrLockedReferenceThread(CsrThread);
CsrReleaseProcessLock();
/* This is an API call, get the Server ID */
ServerId = CSR_API_NUMBER_TO_SERVER_ID(ReceiveMsg.ApiNumber);
/* Make sure that the ID is within limits, and the Server DLL loaded */
ServerDll = NULL;
if ((ServerId >= CSR_SERVER_DLL_MAX) ||
(!(ServerDll = CsrLoadedServerDll[ServerId])))
{
/* We are beyond the Maximum Server ID */
#ifdef CSR_DBG
DPRINT1("CSRSS: %lx is invalid ServerDllIndex (%08x)\n",
ServerId, ServerDll);
if (NtCurrentPeb()->BeingDebugged) DbgBreakPoint();
#endif
ReplyPort = CsrApiPort;
ReplyMsg = &ReceiveMsg;
ReplyMsg->Status = STATUS_ILLEGAL_FUNCTION;
CsrDereferenceThread(CsrThread);
continue;
}
/* Get the API ID, normalized with our Base ID */
ApiId = CSR_API_NUMBER_TO_API_ID(ReceiveMsg.ApiNumber) - ServerDll->ApiBase;
/* Make sure that the ID is within limits, and the entry exists */
if (ApiId >= ServerDll->HighestApiSupported)
{
#ifdef CSR_DBG
/* We are beyond the Maximum API ID, or it doesn't exist */
DPRINT1("CSRSS: %lx is invalid ApiTableIndex for %Z\n",
CSR_API_NUMBER_TO_API_ID(ReceiveMsg.ApiNumber),
&ServerDll->Name);
#endif
ReplyPort = CsrApiPort;
ReplyMsg = &ReceiveMsg;
ReplyMsg->Status = STATUS_ILLEGAL_FUNCTION;
CsrDereferenceThread(CsrThread);
continue;
}
#ifdef CSR_DBG
if (CsrDebug & 2)
{
DPRINT1("[%02x] CSRSS: [%02x,%02x] - %s Api called from %08x, Process %08x - %08x\n",
Teb->ClientId.UniqueThread,
ReceiveMsg.Header.ClientId.UniqueProcess,
ReceiveMsg.Header.ClientId.UniqueThread,
ServerDll->NameTable[ApiId],
CsrThread,
CsrThread->Process,
CsrProcess);
}
#endif
/* Assume success */
ReplyMsg = &ReceiveMsg;
ReceiveMsg.Status = STATUS_SUCCESS;
/* Now we reply to a particular client */
ReplyPort = CsrThread->Process->ClientPort;
/* Check if there's a capture buffer */
if (ReceiveMsg.CsrCaptureData)
{
/* Capture the arguments */
if (!CsrCaptureArguments(CsrThread, &ReceiveMsg))
{
/* Ignore this message if we failed to get the arguments */
CsrDereferenceThread(CsrThread);
continue;
}
}
/* Validation complete, start SEH */
_SEH2_TRY
{
/* Make sure we have enough threads */
CsrpCheckRequestThreads();
Teb->CsrClientThread = CsrThread;
/* Call the API, get the reply code and return the result */
ReplyCode = CsrReplyImmediately;
ReplyMsg->Status = ServerDll->DispatchTable[ApiId](&ReceiveMsg, &ReplyCode);
/* Increase the static thread count */
InterlockedIncrementUL(&CsrpStaticThreadCount);
Teb->CsrClientThread = CurrentThread;
if (ReplyCode == CsrReplyAlreadySent)
{
if (ReceiveMsg.CsrCaptureData)
{
CsrReleaseCapturedArguments(&ReceiveMsg);
}
ReplyMsg = NULL;
ReplyPort = CsrApiPort;
CsrDereferenceThread(CsrThread);
}
else if (ReplyCode == CsrReplyDeadClient)
{
/* Reply to the death message */
NTSTATUS Status2;
Status2 = NtReplyPort(ReplyPort, &ReplyMsg->Header);
if (!NT_SUCCESS(Status2))
DPRINT1("CSRSS: Error while replying to the death message, Status 0x%lx\n", Status2);
/* Reply back to the API port now */
ReplyMsg = NULL;
ReplyPort = CsrApiPort;
CsrDereferenceThread(CsrThread);
}
else if (ReplyCode == CsrReplyPending)
{
ReplyMsg = NULL;
ReplyPort = CsrApiPort;
}
else
{
if (ReceiveMsg.CsrCaptureData)
{
CsrReleaseCapturedArguments(&ReceiveMsg);
}
CsrDereferenceThread(CsrThread);
}
}
_SEH2_EXCEPT(CsrUnhandledExceptionFilter(_SEH2_GetExceptionInformation()))
{
ReplyMsg = NULL;
ReplyPort = CsrApiPort;
}
_SEH2_END;
}
/* We're out of the loop for some reason, terminate! */
NtTerminateThread(NtCurrentThread(), Status);
return Status;
}
/*++
* @name CsrApiPortInitialize
*
* The CsrApiPortInitialize routine initializes the LPC Port used for
* communications with the Client/Server Runtime (CSR) and initializes the
* static thread that will handle connection requests and APIs.
*
* @param None
*
* @return STATUS_SUCCESS in case of success, STATUS_UNSUCCESSFUL otherwise.
*
* @remarks None.
*
*--*/
NTSTATUS
NTAPI
CsrApiPortInitialize(VOID)
{
ULONG Size;
OBJECT_ATTRIBUTES ObjectAttributes;
NTSTATUS Status;
HANDLE hRequestEvent, hThread;
CLIENT_ID ClientId;
PLIST_ENTRY ListHead, NextEntry;
PCSR_THREAD ServerThread;
/* Calculate how much space we'll need for the Port Name */
Size = CsrDirectoryName.Length + sizeof(CSR_PORT_NAME) + sizeof(WCHAR);
/* Create the buffer for it */
CsrApiPortName.Buffer = RtlAllocateHeap(CsrHeap, 0, Size);
if (!CsrApiPortName.Buffer) return STATUS_NO_MEMORY;
/* Setup the rest of the empty string */
CsrApiPortName.Length = 0;
CsrApiPortName.MaximumLength = (USHORT)Size;
RtlAppendUnicodeStringToString(&CsrApiPortName, &CsrDirectoryName);
RtlAppendUnicodeToString(&CsrApiPortName, UNICODE_PATH_SEP);
RtlAppendUnicodeToString(&CsrApiPortName, CSR_PORT_NAME);
if (CsrDebug & 1)
{
DPRINT1("CSRSS: Creating %wZ port and associated threads\n", &CsrApiPortName);
DPRINT1("CSRSS: sizeof( CONNECTINFO ) == %ld sizeof( API_MSG ) == %ld\n",
sizeof(CSR_API_CONNECTINFO), sizeof(CSR_API_MESSAGE));
}
/* FIXME: Create a Security Descriptor */
/* Initialize the Attributes */
InitializeObjectAttributes(&ObjectAttributes,
&CsrApiPortName,
0,
NULL,
NULL /* FIXME: Use the Security Descriptor */);
/* Create the Port Object */
Status = NtCreatePort(&CsrApiPort,
&ObjectAttributes,
sizeof(CSR_API_CONNECTINFO),
sizeof(CSR_API_MESSAGE),
16 * PAGE_SIZE);
if (NT_SUCCESS(Status))
{
/* Create the event the Port Thread will use */
Status = NtCreateEvent(&hRequestEvent,
EVENT_ALL_ACCESS,
NULL,
SynchronizationEvent,
FALSE);
if (NT_SUCCESS(Status))
{
/* Create the Request Thread */
Status = RtlCreateUserThread(NtCurrentProcess(),
NULL,
TRUE,
0,
0,
0,
(PVOID)CsrApiRequestThread,
(PVOID)hRequestEvent,
&hThread,
&ClientId);
if (NT_SUCCESS(Status))
{
/* Add this as a static thread to CSRSRV */
CsrAddStaticServerThread(hThread, &ClientId, CsrThreadIsServerThread);
/* Get the Thread List Pointers */
ListHead = &CsrRootProcess->ThreadList;
NextEntry = ListHead->Flink;
/* Start looping the list */
while (NextEntry != ListHead)
{
/* Get the Thread */
ServerThread = CONTAINING_RECORD(NextEntry, CSR_THREAD, Link);
/* Start it up */
Status = NtResumeThread(ServerThread->ThreadHandle, NULL);
/* Is this a Server Thread? */
if (ServerThread->Flags & CsrThreadIsServerThread)
{
/* If so, then wait for it to initialize */
Status = NtWaitForSingleObject(hRequestEvent, FALSE, NULL);
ASSERT(NT_SUCCESS(Status));
}
/* Next thread */
NextEntry = NextEntry->Flink;
}
/* We don't need this anymore */
NtClose(hRequestEvent);
}
}
}
/* Return */
return Status;
}
/*++
* @name CsrConnectToUser
* @implemented NT4
*
* The CsrConnectToUser connects to the User subsystem.
*
* @param None
*
* @return A pointer to the CSR Thread
*
* @remarks None.
*
*--*/
PCSR_THREAD
NTAPI
CsrConnectToUser(VOID)
{
NTSTATUS Status;
ANSI_STRING DllName;
UNICODE_STRING TempName;
HANDLE hUser32;
STRING StartupName;
PTEB Teb = NtCurrentTeb();
PCSR_THREAD CsrThread;
BOOLEAN Connected;
/* Check if we didn't already find it */
if (!CsrClientThreadSetup)
{
/* Get the DLL Handle for user32.dll */
RtlInitAnsiString(&DllName, "user32");
RtlAnsiStringToUnicodeString(&TempName, &DllName, TRUE);
Status = LdrGetDllHandle(NULL,
NULL,
&TempName,
&hUser32);
RtlFreeUnicodeString(&TempName);
/* If we got the handle, get the Client Thread Startup Entrypoint */
if (NT_SUCCESS(Status))
{
RtlInitAnsiString(&StartupName,"ClientThreadSetup");
Status = LdrGetProcedureAddress(hUser32,
&StartupName,
0,
(PVOID)&CsrClientThreadSetup);
}
}
/* Connect to user32 */
_SEH2_TRY
{
Connected = CsrClientThreadSetup();
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
Connected = FALSE;
}
_SEH2_END;
if (!Connected)
{
DPRINT1("CSRSS: CsrConnectToUser failed\n");
return NULL;
}
/* Save pointer to this thread in TEB */
CsrAcquireProcessLock();
CsrThread = CsrLocateThreadInProcess(NULL, &Teb->ClientId);
CsrReleaseProcessLock();
if (CsrThread) Teb->CsrClientThread = CsrThread;
/* Return it */
return CsrThread;
}
/*++
* @name CsrQueryApiPort
* @implemented NT4
*
* The CsrQueryApiPort routine returns a handle to the CSR API LPC port.
*
* @param None.
*
* @return A handle to the port.
*
* @remarks None.
*
*--*/
HANDLE
NTAPI
CsrQueryApiPort(VOID)
{
return CsrApiPort;
}
/*++
* @name CsrCaptureArguments
* @implemented NT5.1
*
* The CsrCaptureArguments routine validates a CSR Capture Buffer and
* re-captures it into a server CSR Capture Buffer.
*
* @param CsrThread
* Pointer to the CSR Thread performing the validation.
*
* @param ApiMessage
* Pointer to the CSR API Message containing the Capture Buffer
* that needs to be validated.
*
* @return TRUE if validation succeeded, FALSE otherwise.
*
* @remarks None.
*
*--*/
BOOLEAN
NTAPI
CsrCaptureArguments(IN PCSR_THREAD CsrThread,
IN PCSR_API_MESSAGE ApiMessage)
{
PCSR_PROCESS CsrProcess = CsrThread->Process;
PCSR_CAPTURE_BUFFER ClientCaptureBuffer, ServerCaptureBuffer = NULL;
ULONG_PTR EndOfClientBuffer;
SIZE_T SizeOfBufferThroughOffsetsArray;
SIZE_T BufferDistance;
ULONG Length;
ULONG PointerCount;
PULONG_PTR OffsetPointer;
ULONG_PTR CurrentOffset;
/* Get the buffer we got from whoever called NTDLL */
ClientCaptureBuffer = ApiMessage->CsrCaptureData;
/* Use SEH to validate and capture the client buffer */
_SEH2_TRY
{
/* Check whether at least the buffer's header is inside our mapped section */
if ( ((ULONG_PTR)ClientCaptureBuffer < CsrProcess->ClientViewBase) ||
(((ULONG_PTR)ClientCaptureBuffer + FIELD_OFFSET(CSR_CAPTURE_BUFFER, PointerOffsetsArray))
>= CsrProcess->ClientViewBounds) )
{
#ifdef CSR_DBG
DPRINT1("*** CSRSS: CaptureBuffer outside of ClientView 1\n");
if (NtCurrentPeb()->BeingDebugged) DbgBreakPoint();
#endif
/* Return failure */
ApiMessage->Status = STATUS_INVALID_PARAMETER;
_SEH2_YIELD(return FALSE);
}
/* Capture the buffer length */
Length = ((volatile CSR_CAPTURE_BUFFER*)ClientCaptureBuffer)->Size;
/*
* Now check if the remaining of the buffer is inside our mapped section.
* Take also care for any possible wrap-around of the buffer end-address.
*/
EndOfClientBuffer = (ULONG_PTR)ClientCaptureBuffer + Length;
if ( (EndOfClientBuffer < (ULONG_PTR)ClientCaptureBuffer) ||
(EndOfClientBuffer >= CsrProcess->ClientViewBounds) )
{
#ifdef CSR_DBG
DPRINT1("*** CSRSS: CaptureBuffer outside of ClientView 2\n");
if (NtCurrentPeb()->BeingDebugged) DbgBreakPoint();
#endif
/* Return failure */
ApiMessage->Status = STATUS_INVALID_PARAMETER;
_SEH2_YIELD(return FALSE);
}
/* Capture the pointer count */
PointerCount = ((volatile CSR_CAPTURE_BUFFER*)ClientCaptureBuffer)->PointerCount;
/*
* Check whether the total buffer size and the pointer count are consistent
* -- the array of offsets must be contained inside the buffer.
*/
SizeOfBufferThroughOffsetsArray =
FIELD_OFFSET(CSR_CAPTURE_BUFFER, PointerOffsetsArray) +
(PointerCount * sizeof(PVOID));
if ( (PointerCount > MAXUSHORT) ||
(SizeOfBufferThroughOffsetsArray > Length) )
{
#ifdef CSR_DBG
DPRINT1("*** CSRSS: CaptureBuffer %p has bad length\n", ClientCaptureBuffer);
if (NtCurrentPeb()->BeingDebugged) DbgBreakPoint();
#endif
/* Return failure */
ApiMessage->Status = STATUS_INVALID_PARAMETER;
_SEH2_YIELD(return FALSE);
}
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
#ifdef CSR_DBG
DPRINT1("*** CSRSS: Took exception during capture %x\n", _SEH2_GetExceptionCode());
if (NtCurrentPeb()->BeingDebugged) DbgBreakPoint();
#endif
/* Return failure */
ApiMessage->Status = STATUS_INVALID_PARAMETER;
_SEH2_YIELD(return FALSE);
}
_SEH2_END;
/* We validated the client buffer, now allocate the server buffer */
ServerCaptureBuffer = RtlAllocateHeap(CsrHeap, HEAP_ZERO_MEMORY, Length);
if (!ServerCaptureBuffer)
{
/* We're out of memory */
ApiMessage->Status = STATUS_NO_MEMORY;
return FALSE;
}
/*
* Copy the client's buffer and ensure we use the correct buffer length
* and pointer count we captured and used for validation earlier on.
*/
_SEH2_TRY
{
RtlMoveMemory(ServerCaptureBuffer, ClientCaptureBuffer, Length);
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
#ifdef CSR_DBG
DPRINT1("*** CSRSS: Took exception during capture %x\n", _SEH2_GetExceptionCode());
if (NtCurrentPeb()->BeingDebugged) DbgBreakPoint();
#endif
/* Failure, free the buffer and return */
RtlFreeHeap(CsrHeap, 0, ServerCaptureBuffer);
ApiMessage->Status = STATUS_INVALID_PARAMETER;
_SEH2_YIELD(return FALSE);
}
_SEH2_END;
ServerCaptureBuffer->Size = Length;
ServerCaptureBuffer->PointerCount = PointerCount;
/* Calculate the difference between our buffer and the client's */
BufferDistance = (ULONG_PTR)ServerCaptureBuffer - (ULONG_PTR)ClientCaptureBuffer;
/*
* All the pointer offsets correspond to pointers that point
* to the server data buffer instead of the client one.
*/
// PointerCount = ServerCaptureBuffer->PointerCount;
OffsetPointer = ServerCaptureBuffer->PointerOffsetsArray;
while (PointerCount--)
{
CurrentOffset = *OffsetPointer;
if (CurrentOffset != 0)
{
/*
* Check whether the offset is pointer-aligned and whether
* it points inside CSR_API_MESSAGE::Data.ApiMessageData.
*/
if ( ((CurrentOffset & (sizeof(PVOID)-1)) != 0) ||
(CurrentOffset < FIELD_OFFSET(CSR_API_MESSAGE, Data.ApiMessageData)) ||
(CurrentOffset >= sizeof(CSR_API_MESSAGE)) )
{
#ifdef CSR_DBG
DPRINT1("*** CSRSS: CaptureBuffer MessagePointer outside of message\n");
if (NtCurrentPeb()->BeingDebugged) DbgBreakPoint();
#endif
/* Invalid pointer, fail */
ApiMessage->Status = STATUS_INVALID_PARAMETER;
break;
}
/* Get the pointer corresponding to the offset */
CurrentOffset += (ULONG_PTR)ApiMessage;
/* Validate the bounds of the current pointed pointer */
if ( (*(PULONG_PTR)CurrentOffset >= ((ULONG_PTR)ClientCaptureBuffer +
SizeOfBufferThroughOffsetsArray)) &&
(*(PULONG_PTR)CurrentOffset <= (EndOfClientBuffer - sizeof(PVOID))) )
{
/* Modify the pointed pointer to take into account its new position */
*(PULONG_PTR)CurrentOffset += BufferDistance;
}
else
{
#ifdef CSR_DBG
DPRINT1("*** CSRSS: CaptureBuffer MessagePointer outside of ClientView\n");
if (NtCurrentPeb()->BeingDebugged) DbgBreakPoint();
#endif
/* Invalid pointer, fail */
ApiMessage->Status = STATUS_INVALID_PARAMETER;
break;
}
}
++OffsetPointer;
}
/* Check if we got success */
if (ApiMessage->Status != STATUS_SUCCESS)
{
/* Failure, free the buffer and return */
RtlFreeHeap(CsrHeap, 0, ServerCaptureBuffer);
return FALSE;
}
else
{
/* Success, save the previous buffer and use the server capture buffer */
ServerCaptureBuffer->PreviousCaptureBuffer = ClientCaptureBuffer;
ApiMessage->CsrCaptureData = ServerCaptureBuffer;
}
/* Success */
return TRUE;
}
/*++
* @name CsrReleaseCapturedArguments
* @implemented NT5.1
*
* The CsrReleaseCapturedArguments routine releases a Capture Buffer
* that was previously captured with CsrCaptureArguments.
*
* @param ApiMessage
* Pointer to the CSR API Message containing the Capture Buffer
* that needs to be released.
*
* @return None.
*
* @remarks None.
*
*--*/
VOID
NTAPI
CsrReleaseCapturedArguments(IN PCSR_API_MESSAGE ApiMessage)
{
PCSR_CAPTURE_BUFFER ServerCaptureBuffer, ClientCaptureBuffer;
SIZE_T BufferDistance;
ULONG PointerCount;
PULONG_PTR OffsetPointer;
ULONG_PTR CurrentOffset;
/* Get the server capture buffer */
ServerCaptureBuffer = ApiMessage->CsrCaptureData;
/* Do not continue if there is no captured buffer */
if (!ServerCaptureBuffer) return;
/* If there is one, get the corresponding client capture buffer */
ClientCaptureBuffer = ServerCaptureBuffer->PreviousCaptureBuffer;
/* Free the previous one and use again the client capture buffer */
ServerCaptureBuffer->PreviousCaptureBuffer = NULL;
ApiMessage->CsrCaptureData = ClientCaptureBuffer;
/* Calculate the difference between our buffer and the client's */
BufferDistance = (ULONG_PTR)ServerCaptureBuffer - (ULONG_PTR)ClientCaptureBuffer;
/*
* All the pointer offsets correspond to pointers that point
* to the client data buffer instead of the server one (reverse
* the logic of CsrCaptureArguments()).
*/
PointerCount = ServerCaptureBuffer->PointerCount;
OffsetPointer = ServerCaptureBuffer->PointerOffsetsArray;
while (PointerCount--)
{
CurrentOffset = *OffsetPointer;
if (CurrentOffset != 0)
{
/* Get the pointer corresponding to the offset */
CurrentOffset += (ULONG_PTR)ApiMessage;
/* Modify the pointed pointer to take into account its new position */
*(PULONG_PTR)CurrentOffset -= BufferDistance;
}
++OffsetPointer;
}
/* Copy the data back into the client buffer */
_SEH2_TRY
{
RtlMoveMemory(ClientCaptureBuffer, ServerCaptureBuffer, ServerCaptureBuffer->Size);
}
_SEH2_EXCEPT(EXCEPTION_EXECUTE_HANDLER)
{
#ifdef CSR_DBG
DPRINT1("*** CSRSS: Took exception during release %x\n", _SEH2_GetExceptionCode());
if (NtCurrentPeb()->BeingDebugged) DbgBreakPoint();
#endif
/* Return failure */
ApiMessage->Status = _SEH2_GetExceptionCode();
}
_SEH2_END;
/* Free our allocated buffer */
RtlFreeHeap(CsrHeap, 0, ServerCaptureBuffer);
}
/*++
* @name CsrValidateMessageBuffer
* @implemented NT5.1
*
* The CsrValidateMessageBuffer routine validates a captured message buffer
* present in the CSR Api Message
*
* @param ApiMessage
* Pointer to the CSR API Message containing the CSR Capture Buffer.
*
* @param Buffer
* Pointer to the message buffer to validate.
*
* @param ElementCount
* Number of elements contained in the message buffer.
*
* @param ElementSize
* Size of each element.
*
* @return TRUE if validation succeeded, FALSE otherwise.
*
* @remarks None.
*
*--*/
BOOLEAN
NTAPI
CsrValidateMessageBuffer(IN PCSR_API_MESSAGE ApiMessage,
IN PVOID *Buffer,
IN ULONG ElementCount,
IN ULONG ElementSize)
{
PCSR_CAPTURE_BUFFER CaptureBuffer = ApiMessage->CsrCaptureData;
SIZE_T BufferDistance = (ULONG_PTR)Buffer - (ULONG_PTR)ApiMessage;
ULONG PointerCount;
PULONG_PTR OffsetPointer;
/*
* Check whether we have a valid buffer pointer, elements
* of non-trivial size and that we don't overflow.
*/
if (!Buffer || ElementSize == 0 ||
(ULONGLONG)ElementCount * ElementSize > (ULONGLONG)MAXULONG)
{
return FALSE;
}
/* Check if didn't get a buffer and there aren't any arguments to check */
// if (!*Buffer && (ElementCount * ElementSize == 0))
if (!*Buffer && ElementCount == 0) // Here ElementSize != 0 therefore only ElementCount can be == 0
return TRUE;
/* Check if we have no capture buffer */
if (!CaptureBuffer)
{
/* In this case, succeed only if the caller is CSRSS */
if (NtCurrentTeb()->ClientId.UniqueProcess ==
ApiMessage->Header.ClientId.UniqueProcess)
{
return TRUE;
}
}
else
{
/* Make sure that there is still space left in the capture buffer */
if ((CaptureBuffer->Size - (ULONG_PTR)*Buffer + (ULONG_PTR)CaptureBuffer) >=
(ElementCount * ElementSize))
{
/* Perform the validation test */
PointerCount = CaptureBuffer->PointerCount;
OffsetPointer = CaptureBuffer->PointerOffsetsArray;
while (PointerCount--)
{
/*
* Find in the array, the pointer offset (from the
* API message) that corresponds to the buffer.
*/
if (*OffsetPointer == BufferDistance)
{
return TRUE;
}
++OffsetPointer;
}
}
}
/* Failure */
#ifdef CSR_DBG
DPRINT1("CSRSRV: Bad message buffer %p\n", ApiMessage);
if (NtCurrentPeb()->BeingDebugged) DbgBreakPoint();
#endif
return FALSE;
}
/*++
* @name CsrValidateMessageString
* @implemented NT5.1
*
* The CsrValidateMessageString validates a captured Wide-Character String
* present in a CSR API Message.
*
* @param ApiMessage
* Pointer to the CSR API Message containing the CSR Capture Buffer.
*
* @param MessageString
* Pointer to the buffer containing the string to validate.
*
* @return TRUE if validation succeeded, FALSE otherwise.
*
* @remarks None.
*
*--*/
BOOLEAN
NTAPI
CsrValidateMessageString(IN PCSR_API_MESSAGE ApiMessage,
IN PWSTR *MessageString)
{
if (MessageString)
{
return CsrValidateMessageBuffer(ApiMessage,
(PVOID*)MessageString,
wcslen(*MessageString) + 1,
sizeof(WCHAR));
}
else
{
return FALSE;
}
}
/* EOF */