Clean up handling of invalid HWID when running ChromeOS in VMs

chromeos/system/statistics_provider.cc

Index: chromeos/system/statistics_provider.cc
diff --git a/chromeos/system/statistics_provider.cc b/chromeos/system/statistics_provider.cc
index 18c697681aa5e6ff66a2578d14a6db441b2bcc91..70d2232f9844581d369bb7f98ea9efc7e339ae22 100644
--- a/chromeos/system/statistics_provider.cc
+++ b/chromeos/system/statistics_provider.cc
@@ -17,6 +17,7 @@
 #include "base/memory/singleton.h"
 #include "base/path_service.h"
 #include "base/strings/string_number_conversions.h"
+#include "base/strings/string_util.h"
 #include "base/synchronization/cancellation_flag.h"
 #include "base/synchronization/waitable_event.h"
 #include "base/sys_info.h"
@@ -41,13 +42,16 @@ const char* kCrosSystemTool[] = { "/usr/bin/crossystem" };
 const char kCrosSystemEq[] = "=";
 const char kCrosSystemDelim[] = "\n";
 const char kCrosSystemCommentDelim[] = "#";
-const char kCrosSystemUnknownValue[] = "(error)";
+const char kCrosSystemValueError[] = "(error)";
 
 const char kHardwareClassCrosSystemKey[] = "hwid";
-const char kUnknownHardwareClass[] = "unknown";
+const char kHardwareClassValueUnknown[] = "unknown";
 
-// File to get system vendor information from.
+const char kIsVmCrosSystemKey[] = "inside_vm";
+
+// File to get system vendor information from. (x86-only)
 const char kSystemVendorFile[] = "/sys/class/dmi/id/sys_vendor";
+const char kSystemVendorValueUnknown[] = "unknown";
 
 // Key/value delimiters of machine hardware info file. machine-info is generated
 // only for OOBE and enterprise enrollment and may not be present. See
@@ -158,6 +162,9 @@ const char kFirmwareTypeValueDeveloper[] = "developer";
 const char kFirmwareTypeValueNonchrome[] = "nonchrome";
 const char kFirmwareTypeValueNormal[] = "normal";
 const char kHardwareClassKey[] = "hardware_class";
+const char kIsCrosVmKey[] = "inside_cros_vm";

[Daniel Erat, 2016/08/10 16:32:28]

this code is only built for chrome os, so including "cros" here (in both the
constant names and in this value) seems a bit redundant. mind switching to just
something like:

  const char kIsVmKey[] = "is_vm";

?

[norvez, 2016/08/11 17:10:34]

Done.

+const char kIsCrosVmValueTrue[] = "1";
+const char kIsCrosVmValueFalse[] = "0";
 const char kSystemVendorKey[] = "system_vendor";
 const char kOffersCouponCodeKey[] = "ubind_attribute";
 const char kOffersGroupCodeKey[] = "gbind_attribute";
@@ -192,6 +199,10 @@ class StatisticsProviderImpl : public StatisticsProvider {
   bool GetMachineFlag(const std::string& name, bool* result) override;
   void Shutdown() override;
 
+  // Returns true when Chrome OS is running in a VM. NOTE: if crossystem is not
+  // installed it will return false even if Chrome OS is running in a VM.
+  bool IsRunningOnVm() override;
+
   static StatisticsProviderImpl* GetInstance();
 
  protected:
@@ -375,6 +386,14 @@ void StatisticsProviderImpl::Shutdown() {
   cancellation_flag_.Set();  // Cancel any pending loads
 }
 
+bool StatisticsProviderImpl::IsRunningOnVm() {
+  if (!base::SysInfo::IsRunningOnChromeOS())
+    return false;
+  std::string is_vm;
+  return GetMachineStatistic(kIsCrosVmKey, &is_vm) &&
+         is_vm == kIsCrosVmValueTrue;
+}
+
 StatisticsProviderImpl::StatisticsProviderImpl()
     : load_statistics_started_(false),
       on_statistics_loaded_(base::WaitableEvent::ResetPolicy::MANUAL,
@@ -447,12 +466,6 @@ void StatisticsProviderImpl::LoadMachineStatistics(bool load_oem_manifest) {
     }
   }
 
-  if (base::SysInfo::IsRunningOnChromeOS()) {
-    std::string system_vendor;
-    base::ReadFileToString(base::FilePath(kSystemVendorFile), &system_vendor);
-    machine_info_[kSystemVendorKey] = system_vendor;
-  }
-
   parser.GetNameValuePairsFromFile(machine_info_path,
                                    kMachineHardwareInfoEq,
                                    kMachineHardwareInfoDelim);
@@ -466,10 +479,34 @@ void StatisticsProviderImpl::LoadMachineStatistics(bool load_oem_manifest) {
   // Ensure that the hardware class key is present with the expected
   // key name, and if it couldn't be retrieved, that the value is "unknown".
   std::string hardware_class = machine_info_[kHardwareClassCrosSystemKey];
-  if (hardware_class.empty() || hardware_class == kCrosSystemUnknownValue)
-    machine_info_[kHardwareClassKey] = kUnknownHardwareClass;
-  else
+  if (hardware_class.empty() || hardware_class == kCrosSystemValueError) {
+    machine_info_[kHardwareClassKey] = kHardwareClassValueUnknown;
+  } else {
     machine_info_[kHardwareClassKey] = hardware_class;
+  }
+
+  if (base::SysInfo::IsRunningOnChromeOS()) {
+    // By default, assume that this is *not* a VM. If crossystem is not present,
+    // report that we are not in a VM.
+    machine_info_[kIsCrosVmKey] = kIsCrosVmValueFalse;
+    const auto is_vm_iter = machine_info_.find(kIsVmCrosSystemKey);
+    if (is_vm_iter != machine_info_.end() &&
+        is_vm_iter->second == kIsCrosVmValueTrue) {
+      machine_info_[kIsCrosVmKey] = kIsCrosVmValueTrue;
+    }
+
+    // Ensure that the system vendor key is present, in particular it is
+    // potentially useful for VM environments from different vendors.
+    // On non-x86 architectures the value will be "unknown".
+    machine_info_[kSystemVendorKey] = kSystemVendorValueUnknown;
+    std::string system_vendor;
+    if (base::ReadFileToString(base::FilePath(kSystemVendorFile),
+                               &system_vendor)) {
+      base::TrimWhitespaceASCII(system_vendor, base::TRIM_ALL, &system_vendor);
+      if (!system_vendor.empty())
+        machine_info_[kSystemVendorKey] = system_vendor;

[achuithb, 2016/08/10 18:24:58]

Do we actually care about this?

[norvez, 2016/08/11 17:10:34]

Removed system_vendor altogether

+    }
+  }
 
   if (load_oem_manifest) {
     // If kAppOemManifestFile switch is specified, load OEM Manifest file.