BOOLEAN ObDupHandleProcedure( PEPROCESS Process, PVOID HandleTableEntry ) { NTSTATUS Status; POBJECT_TABLE_ENTRY ObjectTableEntry = HandleTableEntry; POBJECT_HEADER ObjectHeader; PVOID Object; ACCESS_STATE AccessState; if (!(ObjectTableEntry->Attributes & OBJ_INHERIT)) { return( FALSE ); } ObjectHeader = (POBJECT_HEADER) (ObjectTableEntry->Attributes & ~OBJ_HANDLE_ATTRIBUTES); Object = &ObjectHeader->Body; #if i386 && !FPO if (NtGlobalFlag & FLG_KERNEL_STACK_TRACE_DB) { AccessState.PreviouslyGrantedAccess = ObpTranslateGrantedAccessIndex( ObjectTableEntry->GrantedAccessIndex ); } else #endif // i386 && !FPO AccessState.PreviouslyGrantedAccess = ObjectTableEntry->GrantedAccess; Status = ObpIncrementHandleCount( ObInheritHandle, Process, Object, ObjectHeader->Type, &AccessState, KernelMode, // BUGBUG this is probably wrong 0 ); if (!NT_SUCCESS( Status )) { return( FALSE ); } ObpIncrPointerCount( ObjectHeader ); return( TRUE ); }
BOOLEAN ObpEnumFindHandleProcedure( PVOID HandleTableEntry, PVOID HandleId, PVOID EnumParameter ) /*++ Routine Description: Call back routine when enumerating an object table to find a handle for a particular object and/or Arguments: argument-name - Supplies | Returns description of argument. . . Return Value: Returns TRUE if a match is found and the enumeration should stop. Returns FALSE otherwise, so the enumeration will continue. --*/ { POBJECT_TABLE_ENTRY ObjectTableEntry = HandleTableEntry; POBJECT_HEADER ObjectHeader; ACCESS_MASK GrantedAccess; ULONG HandleAttributes; POBP_FIND_HANDLE_DATA MatchCriteria = EnumParameter; ObjectHeader = (POBJECT_HEADER)((ULONG)ObjectTableEntry->ObjectHeader & ~OBJ_HANDLE_ATTRIBUTES); if (MatchCriteria->ObjectHeader != NULL && MatchCriteria->ObjectHeader != ObjectHeader ) { return FALSE; } if (MatchCriteria->ObjectType != NULL && MatchCriteria->ObjectType != ObjectHeader->Type ) { return FALSE; } if (ARGUMENT_PRESENT( MatchCriteria->HandleInformation )) { #if i386 && !FPO if (NtGlobalFlag & FLG_KERNEL_STACK_TRACE_DB) { GrantedAccess = ObpTranslateGrantedAccessIndex( ObjectTableEntry->GrantedAccessIndex ); } else #endif // i386 && !FPO GrantedAccess = ObjectTableEntry->GrantedAccess; HandleAttributes = (ULONG)ObjectTableEntry->ObjectHeader & OBJ_HANDLE_ATTRIBUTES; if (MatchCriteria->HandleInformation->HandleAttributes != HandleAttributes || MatchCriteria->HandleInformation->GrantedAccess != GrantedAccess ) { return FALSE; } } return TRUE; }
NTSTATUS NtClose ( IN HANDLE Handle ) /*++ Routine Description: This function is used to close access to the specified handle Arguments: Handle - Supplies the handle being closed Return Value: An appropriate status value --*/ { PHANDLE_TABLE ObjectTable; PHANDLE_TABLE_ENTRY ObjectTableEntry; PVOID Object; ULONG CapturedGrantedAccess; ULONG CapturedAttributes; POBJECT_HEADER ObjectHeader; POBJECT_TYPE ObjectType; NTSTATUS Status; BOOLEAN AttachedToProcess = FALSE; KAPC_STATE ApcState; // // Protect ourselves from being interrupted while we hold a handle table // entry lock // KeEnterCriticalRegion(); try { #if DBG KIRQL SaveIrql; #endif // DBG ObpValidateIrql( "NtClose" ); ObpBeginTypeSpecificCallOut( SaveIrql ); #if DBG // // On checked builds, check that if the Kernel handle bit is set, then // we're coming from Kernel mode. We should probably fail the call if // bit set && !Kmode // if ((Handle != NtCurrentThread()) && (Handle != NtCurrentProcess())) { ASSERT((Handle < 0 ) ? (KeGetPreviousMode() == KernelMode) : TRUE); } #endif // // For the current process we will grab its handle/object table and // translate the handle to its corresponding table entry. If the // call is successful it also lock down the handle table. But first // check for a kernel handle and attach and use that table if so. // if (IsKernelHandle( Handle, KeGetPreviousMode() )) { Handle = DecodeKernelHandle( Handle ); ObjectTable = ObpKernelHandleTable; // // Go to the system process if we have to // if (PsGetCurrentProcess() != PsInitialSystemProcess) { KeStackAttachProcess (&PsInitialSystemProcess->Pcb, &ApcState); AttachedToProcess = TRUE; } } else { ObjectTable = ObpGetObjectTable(); } ObjectTableEntry = ExMapHandleToPointer( ObjectTable, Handle ); // // Check that the specified handle is legitimate otherwise we can // assume the caller just passed in some bogus handle value // if (ObjectTableEntry != NULL) { // // From the object table entry we can grab a pointer to the object // header, get its type and its body // ObjectHeader = (POBJECT_HEADER)(((ULONG_PTR)(ObjectTableEntry->Object)) & ~OBJ_HANDLE_ATTRIBUTES); ObjectType = ObjectHeader->Type; Object = &ObjectHeader->Body; // // If the object type specifies an okay to close procedure then we // need to invoke that callback. If the callback doesn't want us to // close handle then unlock the object table and return the error // to our caller // if (ObjectType->TypeInfo.OkayToCloseProcedure != NULL) { if (!(*ObjectType->TypeInfo.OkayToCloseProcedure)( PsGetCurrentProcess(), Object, Handle )) { ObpEndTypeSpecificCallOut( SaveIrql, "NtClose", ObjectType, Object ); ExUnlockHandleTableEntry( ObjectTable, ObjectTableEntry ); // // If we are attached to the system process then return // back to our caller // if (AttachedToProcess) { KeUnstackDetachProcess(&ApcState); AttachedToProcess = FALSE; } Status = STATUS_HANDLE_NOT_CLOSABLE; leave; } } CapturedAttributes = ObjectTableEntry->ObAttributes; // // If the previous mode was user and the handle is protected from // being closed, then we'll either raise or return an error depending // on the global flags and debugger port situation. // if ((CapturedAttributes & OBJ_PROTECT_CLOSE) != 0) { if (KeGetPreviousMode() != KernelMode) { ExUnlockHandleTableEntry( ObjectTable, ObjectTableEntry ); if ((NtGlobalFlag & FLG_ENABLE_CLOSE_EXCEPTIONS) || (PsGetCurrentProcess()->DebugPort != NULL)) { // // If we are attached to the system process then return // back to our caller // if (AttachedToProcess) { KeUnstackDetachProcess(&ApcState); AttachedToProcess = FALSE; } Status = KeRaiseUserException(STATUS_HANDLE_NOT_CLOSABLE); leave; } else { // // If we are attached to the system process then return // back to our caller // if (AttachedToProcess) { KeUnstackDetachProcess(&ApcState); AttachedToProcess = FALSE; } Status = STATUS_HANDLE_NOT_CLOSABLE; leave; } } else { if ((!PsIsThreadTerminating(PsGetCurrentThread())) && (PsGetCurrentProcess()->Peb != NULL)) { ExUnlockHandleTableEntry( ObjectTable, ObjectTableEntry ); #if DBG // // bugcheck here on checked builds if kernel mode code is // closing a protected handle and process is not exiting. // Ignore if no PEB as this occurs if process is killed // before really starting. // KeBugCheckEx(INVALID_KERNEL_HANDLE, (ULONG_PTR)Handle, 0, 0, 0); #else // // If we are attached to the system process then return // back to our caller // if (AttachedToProcess) { KeUnstackDetachProcess(&ApcState); AttachedToProcess = FALSE; } Status = STATUS_HANDLE_NOT_CLOSABLE; leave; #endif // DBG } } } // // Get the granted access for the handle // #if defined(_X86_) && !FPO if (NtGlobalFlag & FLG_KERNEL_STACK_TRACE_DB) { CapturedGrantedAccess = ObpTranslateGrantedAccessIndex( ObjectTableEntry->GrantedAccessIndex ); } else { CapturedGrantedAccess = ObjectTableEntry->GrantedAccess; } #else CapturedGrantedAccess = ObjectTableEntry->GrantedAccess; #endif // _X86_ && !FPO // // Now remove the handle from the handle table // ExDestroyHandle( ObjectTable, Handle, ObjectTableEntry ); // // perform any auditing required // // // Extract the value of the GenerateOnClose bit stored // after object open auditing is performed. This value // was stored by a call to ObSetGenerateOnClosed. // if (CapturedAttributes & OBJ_AUDIT_OBJECT_CLOSE) { if ( SepAdtAuditingEnabled ) { SeCloseObjectAuditAlarm( Object, (HANDLE)((ULONG_PTR)Handle & ~OBJ_HANDLE_TAGBITS), // Mask off the tagbits defined for OB objects. TRUE ); } } // // Since we took the handle away we need to decrement the objects // handle count, and remove a reference // ObpDecrementHandleCount( PsGetCurrentProcess(), ObjectHeader, ObjectHeader->Type, CapturedGrantedAccess ); ObDereferenceObject( Object ); ObpEndTypeSpecificCallOut( SaveIrql, "NtClose", ObjectType, Object ); // // If we are attached to the system process then return // back to our caller // if (AttachedToProcess) { KeUnstackDetachProcess(&ApcState); AttachedToProcess = FALSE; } // // And return to our caller // Status = STATUS_SUCCESS; leave; } else { // // At this point the input handle did not translate to a valid // object table entry // ObpEndTypeSpecificCallOut( SaveIrql, "NtClose", ObpTypeObjectType, Handle ); // // If we are attached to the system process then return // back to our caller // if (AttachedToProcess) { KeUnstackDetachProcess(&ApcState); AttachedToProcess = FALSE; } // // Now if the handle is not null and it does not represent the // current thread or process then if we're user mode we either raise // or return an error // if ((Handle != NULL) && (Handle != NtCurrentThread()) && (Handle != NtCurrentProcess())) { if (KeGetPreviousMode() != KernelMode) { if ((NtGlobalFlag & FLG_ENABLE_CLOSE_EXCEPTIONS) || (PsGetCurrentProcess()->DebugPort != NULL)) { Status = KeRaiseUserException(STATUS_INVALID_HANDLE); leave; } else { Status = STATUS_INVALID_HANDLE; leave; } } else { // // bugcheck here if kernel debugger is enabled and if kernel mode code is // closing a bogus handle and process is not exiting. Ignore // if no PEB as this occurs if process is killed before // really starting. // if (( !PsIsThreadTerminating(PsGetCurrentThread())) && (PsGetCurrentProcess()->Peb != NULL)) { if (KdDebuggerEnabled) { KeBugCheckEx(INVALID_KERNEL_HANDLE, (ULONG_PTR)Handle, 1, 0, 0); } } } } Status = STATUS_INVALID_HANDLE; leave; } } finally { KeLeaveCriticalRegion(); } return Status; }