modules/rosapps/drivers/vfd/vfdlink.c

   1 /*
   2         vfdlink.c
   3
   4         Virtual Floppy Drive for Windows NT platform
   5         Kernel mode driver: persistent drive letter functions
   6
   7         Copyright (C) 2003-2005 Ken Kato
   8 */
   9
  10 #include "imports.h"
  11 #include "vfddrv.h"
  12 #include "vfddbg.h"
  13
  14 #ifdef ALLOC_PRAGMA
  15 #pragma alloc_text(PAGE, VfdSetLink)
  16 #pragma alloc_text(PAGE, VfdLoadLink)
  17 #pragma alloc_text(PAGE, VfdStoreLink)
  18 #endif  // ALLOC_PRAGMA
  19
  20 //
  21 //      create or remove the persistent drive letter (Windows NT)
  22 //
  23 NTSTATUS
  24 VfdSetLink(
  25         IN      PDEVICE_EXTENSION               DeviceExtension,
  26         IN      CHAR                                    DriveLetter)
  27 {
  28         UNICODE_STRING                          unicode_name;
  29         WCHAR                                           name_buf[15];
  30         NTSTATUS                                        status = STATUS_SUCCESS;
  31
  32         VFDTRACE(VFDINFO, ("[VFD] VfdSetLink - IN\n"));
  33
  34         //      convert lower case into upper case
  35
  36         if (DriveLetter >= 'a' && DriveLetter <= 'z') {
  37                 DriveLetter -= ('a' - 'A');
  38         }
  39
  40         //      check the drive letter range
  41
  42         if (DriveLetter != 0 &&
  43                 (DriveLetter < 'A' || DriveLetter > 'Z')) {
  44                 return STATUS_INVALID_PARAMETER;
  45         }
  46
  47         if (DeviceExtension->DriveLetter &&
  48                 DeviceExtension->DriveLetter != DriveLetter) {
  49                 //
  50                 //      Delete the old drive letter
  51                 //
  52                 name_buf[sizeof(name_buf) - 1] = UNICODE_NULL;
  53
  54                 _snwprintf(name_buf, sizeof(name_buf) - 1,
  55                         L"\\??\\%wc:", DeviceExtension->DriveLetter);
  56
  57                 RtlInitUnicodeString(&unicode_name, name_buf);
  58
  59                 status = IoDeleteSymbolicLink(&unicode_name);
  60
  61                 if (NT_SUCCESS(status)) {
  62                         VFDTRACE(VFDINFO,
  63                                 ("[VFD] Link %ws deleted\n", name_buf));
  64
  65                         DeviceExtension->DriveLetter = 0;
  66                 }
  67                 else if (status != STATUS_OBJECT_NAME_NOT_FOUND) {
  68                         //      the driver letter did not exist in the first place
  69
  70                         VFDTRACE(VFDINFO,
  71                                 ("[VFD] Link %ws not found\n", name_buf));
  72
  73                         DeviceExtension->DriveLetter = 0;
  74                         status = STATUS_SUCCESS;
  75                 }
  76                 else {
  77                         VFDTRACE(VFDWARN,
  78                                 ("[VFD] IoDeleteSymbolicLink %ws - %s\n",
  79                                 name_buf, GetStatusName(status)));
  80                 }
  81         }
  82
  83         if (NT_SUCCESS(status) && DriveLetter) {
  84                 //
  85                 //      Create a new drive letter
  86                 //
  87
  88                 name_buf[sizeof(name_buf) - 1] = UNICODE_NULL;
  89
  90                 _snwprintf(name_buf, sizeof(name_buf) - 1,
  91                         (OsMajorVersion >= 5) ?
  92                         L"\\??\\Global\\%wc:" : L"\\??\\%wc:",
  93                         DriveLetter);
  94
  95                 RtlInitUnicodeString(&unicode_name, name_buf);
  96
  97                 status = IoCreateSymbolicLink(
  98                         &unicode_name, &(DeviceExtension->DeviceName));
  99
 100                 if (NT_SUCCESS(status)) {
 101                         VFDTRACE(VFDINFO, ("[VFD] Link %ws created\n", name_buf));
 102
 103                         DeviceExtension->DriveLetter = DriveLetter;
 104                 }
 105                 else {
 106                         VFDTRACE(VFDWARN,
 107                                 ("[VFD] IoCreateSymbolicLink %ws - %s\n",
 108                                 name_buf, GetStatusName(status)));
 109                 }
 110         }
 111
 112         VFDTRACE(VFDINFO,
 113                 ("[VFD] VfdSetLink - %s\n", GetStatusName(status)));
 114
 115         return status;
 116 }
 117
 118 //
 119 //      load the persistent drive letter from the registry
 120 //
 121 NTSTATUS
 122 VfdLoadLink(
 123         IN      PDEVICE_EXTENSION               DeviceExtension,
 124         IN      PWSTR                                   RegistryPath)
 125 {
 126         RTL_QUERY_REGISTRY_TABLE        params[2];
 127         WCHAR                                           name_buf[20];
 128         ULONG                                           letter;
 129         ULONG                                           zero    = 0;
 130         NTSTATUS                                        status;
 131
 132         VFDTRACE(VFDINFO, ("[VFD] VfdLoadLink - IN\n"));
 133
 134         RtlZeroMemory(params, sizeof(params));
 135
 136         name_buf[sizeof(name_buf) - 1] = UNICODE_NULL;
 137
 138         _snwprintf(name_buf, sizeof(name_buf) - 1,
 139                 VFD_REG_DRIVE_LETTER L"%lu",
 140                 DeviceExtension->DeviceNumber);
 141
 142         params[0].Flags                 = RTL_QUERY_REGISTRY_DIRECT;
 143         params[0].Name                  = name_buf;
 144         params[0].EntryContext  = &letter;
 145         params[0].DefaultType   = REG_DWORD;
 146         params[0].DefaultData   = &zero;
 147         params[0].DefaultLength = sizeof(ULONG);
 148
 149         status = RtlQueryRegistryValues(
 150                 RTL_REGISTRY_ABSOLUTE | RTL_REGISTRY_OPTIONAL,
 151                 RegistryPath, &params[0], NULL, NULL);
 152
 153         VFDTRACE(VFDINFO,
 154                 ("[VFD] Drive letter '%wc' loaded from the registry\n",
 155                 letter ? letter : ' '));
 156
 157         DeviceExtension->DriveLetter = (CHAR)letter;
 158
 159         VFDTRACE(VFDINFO,
 160                 ("[VFD] VfdLoadLink - %s\n", GetStatusName(status)));
 161
 162         return status;
 163 }
 164
 165 //
 166 //      store the persistent drive letter into the registry
 167 //
 168 NTSTATUS
 169 VfdStoreLink(
 170         IN      PDEVICE_EXTENSION               DeviceExtension)
 171 {
 172         PVFD_DRIVER_EXTENSION           driver_extension;
 173         WCHAR                                           name_buf[20];
 174         ULONG                                           letter;
 175         NTSTATUS                                        status;
 176
 177         VFDTRACE(VFDINFO, ("[VFD] VfdStoreLink - IN\n"));
 178
 179 #ifdef VFD_PNP
 180         driver_extension = IoGetDriverObjectExtension(
 181                 DeviceExtension->device_object->DriverObject,
 182                 VFD_DRIVER_EXTENSION_ID);
 183 #else   // VFD_PNP
 184         driver_extension = DeviceExtension->DriverExtension;
 185 #endif  // VFD_PNP
 186
 187         if (!driver_extension ||
 188                 !driver_extension->RegistryPath.Buffer) {
 189
 190                 VFDTRACE(VFDWARN, ("[VFD] Registry Path not present.\n"));
 191                 VFDTRACE(VFDINFO, ("[VFD] VfdStoreLinks - OUT\n"));
 192                 return STATUS_DRIVER_INTERNAL_ERROR;
 193         }
 194
 195         name_buf[sizeof(name_buf) - 1] = UNICODE_NULL;
 196
 197         _snwprintf(name_buf, sizeof(name_buf) - 1,
 198                 VFD_REG_DRIVE_LETTER L"%lu",
 199                 DeviceExtension->DeviceNumber);
 200
 201         letter = DeviceExtension->DriveLetter;
 202
 203         status = RtlWriteRegistryValue(
 204                 RTL_REGISTRY_ABSOLUTE,
 205                 driver_extension->RegistryPath.Buffer,
 206                 name_buf,
 207                 REG_DWORD,
 208                 &letter,
 209                 sizeof(ULONG));
 210
 211         if (!NT_SUCCESS(status)) {
 212                 VFDTRACE(VFDWARN,
 213                         ("[VFD] RtlWriteRegistryValue - %s\n",
 214                         GetStatusName(status)));
 215         }
 216         else {
 217                 VFDTRACE(VFDINFO,
 218                         ("[VFD] Drive letter '%wc' stored into the registry\n",
 219                         letter ? letter : L' '));
 220         }
 221
 222         VFDTRACE(VFDINFO,
 223                 ("[VFD] VfdStoreLink - %s\n", GetStatusName(status)));
 224
 225         return status;
 226 }