Refactor getting a serial number on mac to all use a common utility function.

Change-Id: I5eb6b0d6b6d333a705294a3334547268cb4fdd70
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1954640
Reviewed-by: Nico Weber <thakis@chromium.org>
Reviewed-by: Robert Sesek <rsesek@chromium.org>
Reviewed-by: Julian Pastarmov <pastarmovj@chromium.org>
Reviewed-by: Roger Tawa <rogerta@chromium.org>
Commit-Queue: Tim Song <tengs@chromium.org>
Cr-Commit-Position: refs/heads/master@{#723557}

base/mac/mac_util.h

@@ -198,6 +198,9 @@ BASE_EXPORT bool ParseModelIdentifier(const std::string& ident,
 // displaying to the user.
 BASE_EXPORT std::string GetOSDisplayName();
 
+// Returns the serial number of the macOS device.
+BASE_EXPORT std::string GetPlatformSerialNumber();
+
 }  // namespace mac
 }  // namespace base
 

base/mac/mac_util.mm

@@ -493,5 +493,28 @@ std::string GetOSDisplayName() {
   return os_name + " " + version_string;
 }
 
+std::string GetPlatformSerialNumber() {
+  base::mac::ScopedIOObject<io_service_t> expert_device(
+      IOServiceGetMatchingService(kIOMasterPortDefault,
+                                  IOServiceMatching("IOPlatformExpertDevice")));
+  if (!expert_device) {
+    DLOG(ERROR) << "Error retrieving the machine serial number.";
+    return std::string();
+  }
+
+  base::ScopedCFTypeRef<CFTypeRef> serial_number(
+      IORegistryEntryCreateCFProperty(expert_device,
+                                      CFSTR(kIOPlatformSerialNumberKey),
+                                      kCFAllocatorDefault, 0));
+  CFStringRef serial_number_cfstring =
+      base::mac::CFCast<CFStringRef>(serial_number);
+  if (!serial_number_cfstring) {
+    DLOG(ERROR) << "Error retrieving the machine serial number.";
+    return std::string();
+  }
+
+  return base::SysCFStringRefToUTF8(serial_number_cfstring);
+}
+
 }  // namespace mac
 }  // namespace base

chrome/browser/extensions/api/enterprise_reporting_private/device_info_fetcher_mac.mm

@@ -5,12 +5,14 @@
 #include "chrome/browser/extensions/api/enterprise_reporting_private/device_info_fetcher_mac.h"
 
 #import <Foundation/Foundation.h>
-#import <IOKit/IOKitLib.h>
-#import <sys/sysctl.h>
+
+#include <IOKit/IOKitLib.h>
+#include <sys/sysctl.h>
 
 #include "base/files/file_util.h"
 #include "base/logging.h"
 #include "base/mac/foundation_util.h"
+#include "base/mac/mac_util.h"
 #include "base/mac/scoped_cftyperef.h"
 #include "base/mac/scoped_ioobject.h"
 #include "base/process/launch.h"
@@ -38,26 +40,8 @@ std::string GetDeviceHostName() {
   return net::GetHostName();
 }
 
-// This approach was described here:
-// https://developer.apple.com/library/content/technotes/tn1103/_index.html
 std::string GetSerialNumber() {
-  std::string serial_number;
-  base::mac::ScopedIOObject<io_service_t> platform_expert(
-      IOServiceGetMatchingService(kIOMasterPortDefault,
-                                  IOServiceMatching("IOPlatformExpertDevice")));
-
-  if (platform_expert) {
-    base::ScopedCFTypeRef<CFTypeRef> serial_number_cf_string(
-        IORegistryEntryCreateCFProperty(platform_expert,
-                                        CFSTR(kIOPlatformSerialNumberKey),
-                                        kCFAllocatorDefault, 0));
-    if (serial_number_cf_string) {
-      serial_number = base::SysCFStringRefToUTF8(
-          base::mac::CFCastStrict<CFStringRef>(serial_number_cf_string));
-    }
-  }
-
-  return serial_number;
+  return base::mac::GetPlatformSerialNumber();
 }
 
 enterprise_reporting_private::SettingValue GetScreenlockSecured() {

chrome/browser/policy/browser_dm_token_storage_mac.mm

@@ -15,6 +15,7 @@
 #include "base/hash/sha1.h"
 #include "base/logging.h"
 #include "base/mac/foundation_util.h"
+#include "base/mac/mac_util.h"
 #include "base/mac/scoped_cftyperef.h"
 #include "base/mac/scoped_ioobject.h"
 #include "base/no_destructor.h"
@@ -179,27 +180,7 @@ BrowserDMTokenStorageMac::BrowserDMTokenStorageMac()
 BrowserDMTokenStorageMac::~BrowserDMTokenStorageMac() {}
 
 std::string BrowserDMTokenStorageMac::InitClientId() {
-  // Returns the device s/n.
-  base::mac::ScopedIOObject<io_service_t> expert_device(
-      IOServiceGetMatchingService(kIOMasterPortDefault,
-                                  IOServiceMatching("IOPlatformExpertDevice")));
-  if (!expert_device) {
-    SYSLOG(ERROR) << "Error retrieving the machine serial number.";
-    return std::string();
-  }
-
-  base::ScopedCFTypeRef<CFTypeRef> serial_number(
-      IORegistryEntryCreateCFProperty(expert_device,
-                                      CFSTR(kIOPlatformSerialNumberKey),
-                                      kCFAllocatorDefault, 0));
-  CFStringRef serial_number_cfstring =
-      base::mac::CFCast<CFStringRef>(serial_number);
-  if (!serial_number_cfstring) {
-    SYSLOG(ERROR) << "Error retrieving the machine serial number.";
-    return std::string();
-  }
-
-  return base::SysCFStringRefToUTF8(serial_number_cfstring);
+  return base::mac::GetPlatformSerialNumber();
 }
 
 std::string BrowserDMTokenStorageMac::InitEnrollmentToken() {

rlz/mac/lib/machine_id_mac.cc

@@ -12,11 +12,11 @@
 
 #include "base/logging.h"
 #include "base/mac/foundation_util.h"
+#include "base/mac/mac_util.h"
 #include "base/mac/scoped_cftyperef.h"
 #include "base/mac/scoped_ioobject.h"
 #include "base/strings/string16.h"
 #include "base/strings/stringprintf.h"
-#include "base/strings/sys_string_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 
 namespace rlz_lib {
@@ -97,27 +97,6 @@ bool GetMacAddress(unsigned char* buffer, size_t size) {
   return result;
 }
 
-CFStringRef CopySerialNumber() {
-  base::mac::ScopedIOObject<io_service_t> expert_device(
-      IOServiceGetMatchingService(kIOMasterPortDefault,
-          IOServiceMatching("IOPlatformExpertDevice")));
-  if (!expert_device)
-    return NULL;
-
-  base::ScopedCFTypeRef<CFTypeRef> serial_number(
-      IORegistryEntryCreateCFProperty(expert_device,
-                                      CFSTR(kIOPlatformSerialNumberKey),
-                                      kCFAllocatorDefault,
-                                      0));
-  CFStringRef serial_number_cfstring =
-      base::mac::CFCast<CFStringRef>(serial_number);
-  if (!serial_number_cfstring)
-    return NULL;
-
-  ignore_result(serial_number.release());
-  return serial_number_cfstring;
-}
-
 }  // namespace
 
 bool GetRawMachineId(base::string16* data, int* more_data) {
@@ -134,12 +113,11 @@ bool GetRawMachineId(base::string16* data, int* more_data) {
   // A MAC address is enough to uniquely identify a machine, but it's only 6
   // bytes, 3 of which are manufacturer-determined. To make brute-forcing the
   // SHA1 of this harder, also append the system's serial number.
-  CFStringRef serial = CopySerialNumber();
-  if (serial) {
+  std::string serial = base::mac::GetPlatformSerialNumber();
+  if (!serial.empty()) {
     if (!data->empty())
       *data += base::UTF8ToUTF16(" ");
-    *data += base::UTF8ToUTF16("serial:") + base::SysCFStringRefToUTF16(serial);
-    CFRelease(serial);
+    *data += base::UTF8ToUTF16("serial:") + base::UTF8ToUTF16(serial);
   }
 
   // On windows, this is set to the volume id. Since it's not scrambled before