commit 344417eda5adda1c2efde884e94368a7a4c77034
author Ben Chan <benchan@chromium.org> Fri Feb 14 07:21:17 2014
committer chrome-internal-fetch <chrome-internal-fetch@google.com> Fri Feb 14 22:30:02 2014
tree adc58f92e19d56532d29e736b9e031a3d6238d57
parent 851ebba926dd0a6459d60b662ab44bce09ffc0cd

Hide special partitions on Chrome OS recovery media.

This CL changes cros-disks to use partition type UUIDs, instead of
filesystem labels, to identify and hide the following special partitions
on Chrome OS recovery media:
  - EFI system partition
  - Chrome OS kernel
  - Chrome OS root filesystem
  - Chrome OS firmware
  - Chrome OS reserved

BUG=chromium:260961
TEST=Tested the following:
1. Build and run unit tests.
2. Run platform_CrosDisksFilesystem test.
3. Insert a Chrome OS recovery USB drive and verify that the special
   partitions on the drive are not mounted by the Files app.

Change-Id: Idc6e120745fbd58373970645dd24481cc5411c5a
Reviewed-on: https://chromium-review.googlesource.com/186484
Tested-by: Ben Chan <benchan@chromium.org>
Reviewed-by: Toni Barzic <tbarzic@chromium.org>
Commit-Queue: Ben Chan <benchan@chromium.org>

udev_device.cc

diff --git a/udev_device.cc b/udev_device.cc
index fa588aa..c80a2b7 100644
--- a/udev_device.cc
+++ b/udev_device.cc
@@ -46,6 +46,7 @@
 const char kPropertyFilesystemUsage[] = "ID_FS_USAGE";
 const char kPropertyMistSupportedDevice[] = "MIST_SUPPORTED_DEVICE";
 const char kPropertyModel[] = "ID_MODEL";
+const char kPropertyPartitionEntryType[] = "ID_PART_ENTRY_TYPE";
 const char kPropertyPartitionSize[] = "UDISKS_PARTITION_SIZE";
 const char kPropertyPresentationHide[] = "UDISKS_PRESENTATION_HIDE";
 const char kPropertyRotationRate[] = "ID_ATA_ROTATION_RATE_RPM";
@@ -55,8 +56,12 @@
 const char kLoopDevicePathPrefix[] = "/sys/devices/virtual/block/loop";
 const char kUSBDeviceInfoFile[] = "/opt/google/cros-disks/usb-device-info";
 const char kUSBIdentifierDatabase[] = "/usr/share/misc/usb.ids";
-const char* kNonAutoMountableFilesystemLabels[] = {
-  "C-ROOT", "C-STATE", NULL
+const char* kPartitionTypesToHide[] = {
+  "c12a7328-f81f-11d2-ba4b-00a0c93ec93b",  // EFI system partition
+  "fe3a2a5d-4f32-41a7-b725-accc3285a309",  // Chrome OS kernel
+  "3cb8e202-3b7e-47dd-8a3c-7ff2a13cfcec",  // Chrome OS root filesystem
+  "cab6e88e-abf3-4102-a07a-d4bb9be3c1d3",  // Chrome OS firmware
+  "2e0a753d-9e48-43b0-8337-b15192cb1b5e",  // Chrome OS reserved
 };
 
 }  // namespace
@@ -301,16 +306,12 @@
       (GetPartitionCount() > 0))
     return true;
 
-  // TODO(benchan): Find a better way to filter out Chrome OS specific
-  // partitions instead of excluding partitions with certain labels
-  // (e.g. C-ROOT, C-STATE).
-  string filesystem_label = GetPropertyFromBlkId(kPropertyBlkIdFilesystemLabel);
-  if (!filesystem_label.empty()) {
-    for (const char** label = kNonAutoMountableFilesystemLabels;
-        *label; ++label) {
-      if (strcmp(*label, filesystem_label.c_str()) == 0) {
+  // Hide special partitions based on partition type.
+  string partition_type = GetProperty(kPropertyPartitionEntryType);
+  if (!partition_type.empty()) {
+    for (size_t i = 0; i < arraysize(kPartitionTypesToHide); ++i) {
+      if (partition_type == kPartitionTypesToHide[i])
         return true;
-      }
     }
   }
   return false;