implement shareaccess @marinkobabic

dokan-dev · Aug 19, 2015 · ac016e9 · ac016e9
1 parent e6e9964
commit ac016e9
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Showing 4 changed files with 68 additions and 19 deletions.
diff --git a/sys/cleanup.c b/sys/cleanup.c
@@ -166,6 +166,11 @@ DokanCompleteCleanup(
 		FsRtlNotifyCleanup(vcb->NotifySync, &vcb->DirNotifyList, ccb);
 	}
 
+	InterlockedDecrement(&fcb->OpenHandleCount);
+	IoRemoveShareAccess(irpSp->FileObject, &fcb->ShareAccess);
+
+	DDbgPrint("    OpenHandleCount:%d ReferenceCount:%d\n", fcb->OpenHandleCount, fcb->ReferenceCount);
+
     DokanCompleteIrpRequest(irp, status, 0);
 
 	DDbgPrint("<== DokanCompleteCleanup\n");

diff --git a/sys/close.c b/sys/close.c
@@ -115,7 +115,7 @@ Return Value:
 		}
 
 		eventContext->Context = ccb->UserContext;
-		DDbgPrint("   UserContext:%X\n", (ULONG)ccb->UserContext);
+		DDbgPrint("   UserContext:%X RefereceCount:%d OpenHandleCount:%d\n", (ULONG)ccb->UserContext, fcb->ReferenceCount, fcb->OpenHandleCount);
 
 		// copy the file name to be closed
 		eventContext->Operation.Close.FileNameLength = fcb->FileName.Length;

diff --git a/sys/create.c b/sys/create.c
@@ -149,7 +149,7 @@ DokanGetFCB(
 		ExFreePool(FileName);
 	}
 
-	InterlockedIncrement(&fcb->FileCount);
+	InterlockedIncrement(&fcb->ReferenceCount);
 
 	ExReleaseResourceLite(&Vcb->Resource);
 	KeLeaveCriticalRegion();
@@ -174,9 +174,9 @@ DokanFreeFCB(
 	ExAcquireResourceExclusiveLite(&vcb->Resource, TRUE);
 	ExAcquireResourceExclusiveLite(&Fcb->Resource, TRUE);
 
-	InterlockedDecrement(&Fcb->FileCount);
+	InterlockedDecrement(&Fcb->ReferenceCount);
 
-	if (Fcb->FileCount == 0) {
+	if (Fcb->ReferenceCount == 0) {
 
 		RemoveEntryList(&Fcb->NextFCB);
 
@@ -502,14 +502,6 @@ Return Value:
 			fcb->AdvancedFCBHeader.Flags2 &= ~FSRTL_FLAG2_SUPPORTS_FILTER_CONTEXTS;
 		}
 
-		ccb = DokanAllocateCCB(dcb, fcb);
-		if (ccb == NULL) {
-            DDbgPrint("    Was not able to allocate CCB\n");
-			DokanFreeFCB(fcb); // FileName is freed here
-			status = STATUS_INSUFFICIENT_RESOURCES;
-			__leave;
-		}
-
 		//remember FILE_DELETE_ON_CLOSE so than the file can be deleted in close for windows 8
 		if (irpSp->Parameters.Create.Options & FILE_DELETE_ON_CLOSE) {
 			fcb->Flags |= DOKAN_DELETE_ON_CLOSE;
@@ -518,6 +510,34 @@ Return Value:
 			fcb->Flags &= ~DOKAN_DELETE_ON_CLOSE;
 		}
 
+		if (fcb->OpenHandleCount > 0) {
+				/* check the share access conflicts */
+				status = IoCheckShareAccess(irpSp->Parameters.Create.SecurityContext->DesiredAccess,
+				irpSp->Parameters.Create.ShareAccess,
+				irpSp->FileObject,
+				&(fcb->ShareAccess),
+				TRUE);
+			if (!NT_SUCCESS(status)) {
+				DokanFreeFCB(fcb);
+				__leave;
+			}		
+		}
+		else {
+			/* set share access rights */
+			IoSetShareAccess(irpSp->Parameters.Create.SecurityContext->DesiredAccess,
+				irpSp->Parameters.Create.ShareAccess,
+				irpSp->FileObject,
+				&(fcb->ShareAccess));
+		}
+
+		ccb = DokanAllocateCCB(dcb, fcb);
+		if (ccb == NULL) {
+			DDbgPrint("    Was not able to allocate CCB");
+			DokanFreeFCB(fcb); // FileName is freed here
+			status = STATUS_INSUFFICIENT_RESOURCES;
+			__leave;
+		}
+
 		fileObject->FsContext = &fcb->AdvancedFCBHeader;
 		fileObject->FsContext2 = ccb;
 		fileObject->PrivateCacheMap = NULL;
@@ -529,10 +549,19 @@ Return Value:
 
 		if (eventContext == NULL) {
             DDbgPrint("    Was not able to allocate eventContext\n");
+			IoRemoveShareAccess(irpSp->FileObject, &fcb->ShareAccess);
+			fileObject->FsContext = NULL;
+			fileObject->FsContext2 = NULL;
+			fileObject->PrivateCacheMap = NULL;
+			fileObject->SectionObjectPointer = NULL;
+			DokanFreeFCB(fcb);
+			DokanFreeCCB(ccb);
 			status = STATUS_INSUFFICIENT_RESOURCES;
 			__leave;
 		}
 
+		InterlockedIncrement(&fcb->OpenHandleCount);
+
 		eventContext->Context = 0;
 		eventContext->FileFlags |= fcb->Flags;
 
@@ -650,6 +679,8 @@ DokanCompleteCreate(
 		}
 	} else {
 		DDbgPrint("   IRP_MJ_CREATE failed. Free CCB:%X\n", ccb);
+		InterlockedDecrement(&fcb->OpenHandleCount);
+		IoRemoveShareAccess(irpSp->FileObject, &fcb->ShareAccess);
 		DokanFreeCCB(ccb);
 		DokanFreeFCB(fcb);
 	}

diff --git a/sys/dokan.h b/sys/dokan.h
@@ -232,6 +232,12 @@ typedef struct _DokanVolumeControlBlock {
 } DokanVCB, *PDokanVCB;
 
 
+//
+// File Control Block
+//
+// Data that represents an open file
+// There is a single instance of the FCB for every open file
+//
 typedef struct _DokanFileControlBlock
 {
 	FSD_IDENTIFIER				Identifier;
@@ -249,18 +255,27 @@ typedef struct _DokanFileControlBlock
 	ERESOURCE				Resource;
 	LIST_ENTRY				NextCCB;
 
-	LONG					FileCount;
-
 	ULONG					Flags;
 
 	UNICODE_STRING			FileName;
 
-	//uint32 ReferenceCount;
-	//uint32 OpenHandleCount;
-} DokanFCB, *PDokanFCB;
+	// Share Access for the file object
+	SHARE_ACCESS            ShareAccess;
 
+	// Incremented on IRP_MJ_CREATE, decremented on IRP_MJ_CLEANUP
+	LONG                  OpenHandleCount;
 
+	// Incremented on IRP_MJ_CREATE, decremented on IRP_MJ_CLOSE
+	LONG                  ReferenceCount;
+} DokanFCB, *PDokanFCB;
 
+
+//
+// Context Control Block
+//
+// Data that represents one instance of an open file
+// There is one instance of the CCB for every instance of an open file
+//
 typedef struct _DokanContextControlBlock
 {
 	FSD_IDENTIFIER		Identifier;
@@ -274,8 +289,6 @@ typedef struct _DokanContextControlBlock
 	ULONG				SearchPatternLength;
 
 	ULONG				Flags;
-
-	int					FileCount;
 	ULONG				MountId;
 } DokanCCB, *PDokanCCB;