From: Pierre Schweitzer <pierre@reactos.org>
Date: Wed, 25 Dec 2013 22:47:30 +0000 (+0000)
Subject: [MOUNTMGR]
X-Git-Tag: ReactOS-0.3.16~432
X-Git-Url: https://git.reactos.org/?p=reactos.git;a=commitdiff_plain;h=3c03b26a4fba3abef944193bd8a28d2e58f31661;hp=ad8fe5ab9516c561f04cfee8ba667a0cbc943081

[MOUNTMGR]
Implement MountMgrQueryDosVolumePath

svn path=/trunk/; revision=61421
---

diff --git a/reactos/drivers/filters/mountmgr/device.c b/reactos/drivers/filters/mountmgr/device.c
index 9efdf076e41..8d069c95fd7 100644
--- a/reactos/drivers/filters/mountmgr/device.c
+++ b/reactos/drivers/filters/mountmgr/device.c
@@ -27,6 +27,8 @@
 
 #include "mntmgr.h"
 
+#define MAX_DEVICES 0x3E8 /* Matches 1000 devices */
+
 #define NDEBUG
 #include <debug.h>
 
@@ -833,9 +835,224 @@ NTSTATUS
 MountMgrQueryDosVolumePath(IN PDEVICE_EXTENSION DeviceExtension,
                            IN PIRP Irp)
 {
-    UNREFERENCED_PARAMETER(DeviceExtension);
-    UNREFERENCED_PARAMETER(Irp);
-    return STATUS_NOT_IMPLEMENTED;
+    NTSTATUS Status;
+    ULONG DevicesFound;
+    PIO_STACK_LOCATION Stack;
+    PLIST_ENTRY SymlinksEntry;
+    UNICODE_STRING SymbolicName;
+    PMOUNTMGR_TARGET_NAME Target;
+    PWSTR DeviceString, OldBuffer;
+    USHORT DeviceLength, OldLength;
+    PDEVICE_INFORMATION DeviceInformation;
+    PSYMLINK_INFORMATION SymlinkInformation;
+    PASSOCIATED_DEVICE_ENTRY AssociatedDevice;
+
+    Stack = IoGetNextIrpStackLocation(Irp);
+
+    /* Validate input size */
+    if (Stack->Parameters.DeviceIoControl.InputBufferLength < sizeof(MOUNTMGR_TARGET_NAME))
+    {
+        return STATUS_INVALID_PARAMETER;
+    }
+
+    /* Ensure we have received UNICODE_STRING */
+    Target = (PMOUNTMGR_TARGET_NAME)Irp->AssociatedIrp.SystemBuffer;
+    if (Target->DeviceNameLength & 1)
+    {
+        return STATUS_INVALID_PARAMETER;
+    }
+
+    /* Validate the entry structure size */
+    if (Target->DeviceNameLength + sizeof(UNICODE_NULL) > Stack->Parameters.DeviceIoControl.InputBufferLength)
+    {
+        return STATUS_INVALID_PARAMETER;
+    }
+
+    /* Ensure we can at least return needed size */
+    if (Stack->Parameters.DeviceIoControl.OutputBufferLength < sizeof(ULONG))
+    {
+        return STATUS_INVALID_PARAMETER;
+    }
+
+    /* Construct string for query */
+    SymbolicName.Length = Target->DeviceNameLength;
+    SymbolicName.MaximumLength = Target->DeviceNameLength + sizeof(UNICODE_NULL);
+    SymbolicName.Buffer = Target->DeviceName;
+
+    /* Find device with our info */
+    Status = FindDeviceInfo(DeviceExtension, &SymbolicName, FALSE, &DeviceInformation);
+    if (!NT_SUCCESS(Status))
+    {
+        return Status;
+    }
+
+    DeviceLength = 0;
+    DeviceString = NULL;
+    DevicesFound = 0;
+
+    /* Try to find associated device info */
+    while (TRUE)
+    {
+        for (SymlinksEntry = DeviceInformation->SymbolicLinksListHead.Flink;
+             SymlinksEntry != &(DeviceInformation->SymbolicLinksListHead);
+             SymlinksEntry = SymlinksEntry->Flink)
+        {
+            SymlinkInformation = CONTAINING_RECORD(SymlinksEntry, SYMLINK_INFORMATION, SymbolicLinksListEntry);
+
+            /* Try to find with drive letter */
+            if (MOUNTMGR_IS_DRIVE_LETTER(&SymlinkInformation->Name) && SymlinkInformation->Online)
+            {
+                break;
+            }
+        }
+
+        /* We didn't find, break */
+        if (SymlinksEntry == &(DeviceInformation->SymbolicLinksListHead))
+        {
+            break;
+        }
+
+        /* It doesn't have associated device, go to fallback method */
+        if (IsListEmpty(&DeviceInformation->AssociatedDevicesHead))
+        {
+            goto TryWithVolumeName;
+        }
+
+        /* Create a string with the information about the device */
+        AssociatedDevice = CONTAINING_RECORD(&(DeviceInformation->SymbolicLinksListHead), ASSOCIATED_DEVICE_ENTRY, AssociatedDevicesEntry);
+        OldLength = DeviceLength;
+        OldBuffer = DeviceString;
+        DeviceLength += AssociatedDevice->String.Length;
+        DeviceString = AllocatePool(DeviceLength);
+        if (!DeviceString)
+        {
+            if (OldBuffer)
+            {
+                FreePool(OldBuffer);
+            }
+
+            return STATUS_INSUFFICIENT_RESOURCES;
+        }
+
+        /* Store our info and previous if any */
+        RtlCopyMemory(DeviceString, AssociatedDevice->String.Buffer, AssociatedDevice->String.Length);
+        if (OldBuffer)
+        {
+            RtlCopyMemory(&DeviceString[AssociatedDevice->String.Length / sizeof(WCHAR)], OldBuffer, OldLength);
+            FreePool(OldBuffer);
+        }
+
+        /* Count and continue looking */
+        ++DevicesFound;
+        DeviceInformation = AssociatedDevice->DeviceInformation;
+
+        /* If too many devices, try another way */
+        if (DevicesFound > MAX_DEVICES) /*  1000 */
+        {
+            goto TryWithVolumeName;
+        }
+    }
+
+    /* Reallocate our string, so that we can prepend disk letter */
+    OldBuffer = DeviceString;
+    OldLength = DeviceLength;
+    DeviceLength += 2 * sizeof(WCHAR);
+    DeviceString = AllocatePool(DeviceLength);
+    if (!DeviceString)
+    {
+        if (OldBuffer)
+        {
+            FreePool(OldBuffer);
+        }
+
+        return STATUS_INSUFFICIENT_RESOURCES;
+    }
+
+    /* Get the letter */
+    DeviceString[0] = SymlinkInformation->Name.Buffer[12];
+    DeviceString[1] = L':';
+
+    /* And copy the rest */
+    if (OldBuffer)
+    {
+        RtlCopyMemory(&DeviceString[2], OldBuffer, OldLength);
+        FreePool(OldBuffer);
+    }
+
+TryWithVolumeName:
+    /* If we didn't find anything, try differently */
+    if (DeviceLength < 2 * sizeof(WCHAR) || DeviceString[2] != L':')
+    {
+        if (DeviceString)
+        {
+            FreePool(DeviceString);
+            DeviceLength = 0;
+        }
+
+        /* Try to find a volume name matching */
+        for (SymlinksEntry = DeviceInformation->SymbolicLinksListHead.Flink;
+             SymlinksEntry != &(DeviceInformation->SymbolicLinksListHead);
+             SymlinksEntry = SymlinksEntry->Flink)
+        {
+            SymlinkInformation = CONTAINING_RECORD(SymlinksEntry, SYMLINK_INFORMATION, SymbolicLinksListEntry);
+
+            if (MOUNTMGR_IS_VOLUME_NAME(&SymlinkInformation->Name))
+            {
+                break;
+            }
+        }
+
+        /* If found copy */
+        if (SymlinksEntry != &(DeviceInformation->SymbolicLinksListHead))
+        {
+            DeviceLength = SymlinkInformation->Name.Length;
+            DeviceString = AllocatePool(DeviceLength);
+            if (!DeviceString)
+            {
+                return STATUS_INSUFFICIENT_RESOURCES;
+            }
+
+            RtlCopyMemory(DeviceString, SymlinkInformation->Name.Buffer, DeviceLength);
+            /* Ensure we are in the right namespace; [1] can be ? */
+            DeviceString[1] = L'\\';
+        }
+    }
+
+    /* If we found something */
+    if (DeviceString)
+    {
+        /* At least, we will return our length */
+        ((PMOUNTMGR_VOLUME_PATHS)Irp->AssociatedIrp.SystemBuffer)->MultiSzLength = DeviceLength;
+        /* MOUNTMGR_VOLUME_PATHS is a string + a ULONG */
+        Irp->IoStatus.Information = DeviceLength + sizeof(ULONG);
+
+        /* If we have enough room for copying the string */
+        if (sizeof(ULONG) + DeviceLength <= Stack->Parameters.DeviceIoControl.OutputBufferLength)
+        {
+            /* Copy it */
+            if (DeviceLength)
+            {
+                RtlCopyMemory(((PMOUNTMGR_VOLUME_PATHS)Irp->AssociatedIrp.SystemBuffer)->MultiSz, DeviceString, DeviceLength);
+            }
+
+            /* And double zero at its end - this is needed in case of multiple paths which are separated by a single 0 */
+            FreePool(DeviceString);
+            ((PMOUNTMGR_VOLUME_PATHS)Irp->AssociatedIrp.SystemBuffer)->MultiSz[DeviceLength / sizeof(WCHAR)] = 0;
+            ((PMOUNTMGR_VOLUME_PATHS)Irp->AssociatedIrp.SystemBuffer)->MultiSz[DeviceLength / sizeof(WCHAR) + 1] = 0;
+
+            return STATUS_SUCCESS;
+        }
+        else
+        {
+            /* Just return appropriate size and leave */
+            FreePool(DeviceString);
+            Irp->IoStatus.Information = sizeof(ULONG);
+            return STATUS_BUFFER_OVERFLOW;
+        }
+    }
+
+    /* Fail */
+    return STATUS_NOT_FOUND;
 }
 
 NTSTATUS
diff --git a/reactos/drivers/filters/mountmgr/mountmgr.c b/reactos/drivers/filters/mountmgr/mountmgr.c
index 2e78d4e3cbc..d955453ed1d 100644
--- a/reactos/drivers/filters/mountmgr/mountmgr.c
+++ b/reactos/drivers/filters/mountmgr/mountmgr.c
@@ -42,7 +42,6 @@ static const WCHAR Cunc[] = L"\\??\\C:";
 
 /*
  * TODO:
- * - MountMgrQueryDosVolumePath
  * - MountMgrQueryDosVolumePaths
  * - MountMgrQueryVolumePaths
  * - MountMgrValidateBackPointer