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-rw-r--r--onlineupdate/source/update/common/updatehelper.cxx807
1 files changed, 807 insertions, 0 deletions
diff --git a/onlineupdate/source/update/common/updatehelper.cxx b/onlineupdate/source/update/common/updatehelper.cxx
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+++ b/onlineupdate/source/update/common/updatehelper.cxx
@@ -0,0 +1,807 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifdef _WIN32
+#include <windows.h>
+
+// Needed for CreateToolhelp32Snapshot
+#include <tlhelp32.h>
+#ifndef ONLY_SERVICE_LAUNCHING
+
+#include <stdio.h>
+#include "shlobj.h"
+#include "updatehelper.h"
+#include "uachelper.h"
+#include "pathhash.h"
+
+#include <memory>
+
+// Needed for PathAppendW
+#include <shlwapi.h>
+
+BOOL PathAppendSafe(LPWSTR base, LPCWSTR extra);
+
+/**
+ * Obtains the path of a file in the same directory as the specified file.
+ *
+ * @param destinationBuffer A buffer of size MAX_PATH + 1 to store the result.
+ * @param siblingFIlePath The path of another file in the same directory
+ * @param newFileName The filename of another file in the same directory
+ * @return TRUE if successful
+ */
+BOOL
+PathGetSiblingFilePath(LPWSTR destinationBuffer,
+ LPCWSTR siblingFilePath,
+ LPCWSTR newFileName)
+{
+ if (wcslen(siblingFilePath) >= MAX_PATH)
+ {
+ return FALSE;
+ }
+
+ wcsncpy(destinationBuffer, siblingFilePath, MAX_PATH);
+ if (!PathRemoveFileSpecW(destinationBuffer))
+ {
+ return FALSE;
+ }
+
+ if (wcslen(destinationBuffer) + wcslen(newFileName) >= MAX_PATH)
+ {
+ return FALSE;
+ }
+
+ return PathAppendSafe(destinationBuffer, newFileName);
+}
+
+/**
+ * Launch the post update application as the specified user (helper.exe).
+ * It takes in the path of the callback application to calculate the path
+ * of helper.exe. For service updates this is called from both the system
+ * account and the current user account.
+ *
+ * @param installationDir The path to the callback application binary.
+ * @param updateInfoDir The directory where update info is stored.
+ * @param forceSync If true even if the ini file specifies async, the
+ * process will wait for termination of PostUpdate.
+ * @param userToken The user token to run as, if nullptr the current
+ * user will be used.
+ * @return TRUE if there was no error starting the process.
+ */
+BOOL
+LaunchWinPostProcess(const WCHAR *installationDir,
+ const WCHAR *updateInfoDir,
+ bool forceSync,
+ HANDLE userToken)
+{
+ WCHAR workingDirectory[MAX_PATH + 1] = { L'\0' };
+ wcsncpy(workingDirectory, installationDir, MAX_PATH);
+
+ // Launch helper.exe to perform post processing (e.g. registry and log file
+ // modifications) for the update.
+ WCHAR inifile[MAX_PATH + 1] = { L'\0' };
+ wcsncpy(inifile, installationDir, MAX_PATH);
+ if (!PathAppendSafe(inifile, L"updater.ini"))
+ {
+ return FALSE;
+ }
+
+ WCHAR exefile[MAX_PATH + 1];
+ WCHAR exearg[MAX_PATH + 1];
+ WCHAR exeasync[10];
+ bool async = true;
+ if (!GetPrivateProfileStringW(L"PostUpdateWin", L"ExeRelPath", nullptr,
+ exefile, MAX_PATH + 1, inifile))
+ {
+ return FALSE;
+ }
+
+ if (!GetPrivateProfileStringW(L"PostUpdateWin", L"ExeArg", nullptr, exearg,
+ MAX_PATH + 1, inifile))
+ {
+ return FALSE;
+ }
+
+ if (!GetPrivateProfileStringW(L"PostUpdateWin", L"ExeAsync", L"TRUE",
+ exeasync,
+ sizeof(exeasync)/sizeof(exeasync[0]),
+ inifile))
+ {
+ return FALSE;
+ }
+
+ WCHAR exefullpath[MAX_PATH + 1] = { L'\0' };
+ wcsncpy(exefullpath, installationDir, MAX_PATH);
+ if (!PathAppendSafe(exefullpath, exefile))
+ {
+ return false;
+ }
+
+ WCHAR dlogFile[MAX_PATH + 1];
+ if (!PathGetSiblingFilePath(dlogFile, exefullpath, L"uninstall.update"))
+ {
+ return FALSE;
+ }
+
+ WCHAR slogFile[MAX_PATH + 1] = { L'\0' };
+ wcsncpy(slogFile, updateInfoDir, MAX_PATH);
+ if (!PathAppendSafe(slogFile, L"update.log"))
+ {
+ return FALSE;
+ }
+
+ WCHAR dummyArg[14] = { L'\0' };
+ wcsncpy(dummyArg, L"argv0ignored ", sizeof(dummyArg) / sizeof(dummyArg[0]) - 1);
+
+ size_t len = wcslen(exearg) + wcslen(dummyArg);
+ WCHAR *cmdline = (WCHAR *) malloc((len + 1) * sizeof(WCHAR));
+ if (!cmdline)
+ {
+ return FALSE;
+ }
+
+ wcsncpy(cmdline, dummyArg, len);
+ wcscat(cmdline, exearg);
+
+ if (forceSync ||
+ !_wcsnicmp(exeasync, L"false", 6) ||
+ !_wcsnicmp(exeasync, L"0", 2))
+ {
+ async = false;
+ }
+
+ // We want to launch the post update helper app to update the Windows
+ // registry even if there is a failure with removing the uninstall.update
+ // file or copying the update.log file.
+ CopyFileW(slogFile, dlogFile, false);
+
+ STARTUPINFOW si = {sizeof(si), 0};
+ si.lpDesktop = L"";
+ PROCESS_INFORMATION pi = {0};
+
+ bool ok;
+ if (userToken)
+ {
+ ok = CreateProcessAsUserW(userToken,
+ exefullpath,
+ cmdline,
+ nullptr, // no special security attributes
+ nullptr, // no special thread attributes
+ false, // don't inherit filehandles
+ 0, // No special process creation flags
+ nullptr, // inherit my environment
+ workingDirectory,
+ &si,
+ &pi);
+ }
+ else
+ {
+ ok = CreateProcessW(exefullpath,
+ cmdline,
+ nullptr, // no special security attributes
+ nullptr, // no special thread attributes
+ false, // don't inherit filehandles
+ 0, // No special process creation flags
+ nullptr, // inherit my environment
+ workingDirectory,
+ &si,
+ &pi);
+ }
+ free(cmdline);
+ if (ok)
+ {
+ if (!async)
+ WaitForSingleObject(pi.hProcess, INFINITE);
+ CloseHandle(pi.hProcess);
+ CloseHandle(pi.hThread);
+ }
+ return ok;
+}
+
+/**
+ * Starts the upgrade process for update of the service if it is
+ * already installed.
+ *
+ * @param installDir the installation directory where
+ * maintenanceservice_installer.exe is located.
+ * @return TRUE if successful
+ */
+BOOL
+StartServiceUpdate(LPCWSTR installDir)
+{
+ // Get a handle to the local computer SCM database
+ SC_HANDLE manager = OpenSCManager(nullptr, nullptr,
+ SC_MANAGER_ALL_ACCESS);
+ if (!manager)
+ {
+ return FALSE;
+ }
+
+ // Open the service
+ SC_HANDLE svc = OpenServiceW(manager, SVC_NAME,
+ SERVICE_ALL_ACCESS);
+ if (!svc)
+ {
+ CloseServiceHandle(manager);
+ return FALSE;
+ }
+
+ // If we reach here, then the service is installed, so
+ // proceed with upgrading it.
+
+ CloseServiceHandle(manager);
+
+ // The service exists and we opened it, get the config bytes needed
+ DWORD bytesNeeded;
+ if (!QueryServiceConfigW(svc, nullptr, 0, &bytesNeeded) &&
+ GetLastError() != ERROR_INSUFFICIENT_BUFFER)
+ {
+ CloseServiceHandle(svc);
+ return FALSE;
+ }
+
+ // Get the service config information, in particular we want the binary
+ // path of the service.
+ std::unique_ptr<char[]> serviceConfigBuffer = std::make_unique<char[]>(bytesNeeded);
+ if (!QueryServiceConfigW(svc,
+ reinterpret_cast<QUERY_SERVICE_CONFIGW*>(serviceConfigBuffer.get()),
+ bytesNeeded, &bytesNeeded))
+ {
+ CloseServiceHandle(svc);
+ return FALSE;
+ }
+
+ CloseServiceHandle(svc);
+
+ QUERY_SERVICE_CONFIGW &serviceConfig =
+ *reinterpret_cast<QUERY_SERVICE_CONFIGW*>(serviceConfigBuffer.get());
+
+ PathUnquoteSpacesW(serviceConfig.lpBinaryPathName);
+
+ // Obtain the temp path of the maintenance service binary
+ WCHAR tmpService[MAX_PATH + 1] = { L'\0' };
+ if (!PathGetSiblingFilePath(tmpService, serviceConfig.lpBinaryPathName,
+ L"maintenanceservice_tmp.exe"))
+ {
+ return FALSE;
+ }
+
+ // Get the new maintenance service path from the install dir
+ WCHAR newMaintServicePath[MAX_PATH + 1] = { L'\0' };
+ wcsncpy(newMaintServicePath, installDir, MAX_PATH);
+ PathAppendSafe(newMaintServicePath,
+ L"maintenanceservice.exe");
+
+ // Copy the temp file in alongside the maintenance service.
+ // This is a requirement for maintenance service upgrades.
+ if (!CopyFileW(newMaintServicePath, tmpService, FALSE))
+ {
+ return FALSE;
+ }
+
+ // Start the upgrade comparison process
+ STARTUPINFOW si = {0};
+ si.cb = sizeof(STARTUPINFOW);
+ // No particular desktop because no UI
+ si.lpDesktop = L"";
+ PROCESS_INFORMATION pi = {0};
+ WCHAR cmdLine[64] = { '\0' };
+ wcsncpy(cmdLine, L"dummyparam.exe upgrade",
+ sizeof(cmdLine) / sizeof(cmdLine[0]) - 1);
+ BOOL svcUpdateProcessStarted = CreateProcessW(tmpService,
+ cmdLine,
+ nullptr, nullptr, FALSE,
+ 0,
+ nullptr, installDir, &si, &pi);
+ if (svcUpdateProcessStarted)
+ {
+ CloseHandle(pi.hProcess);
+ CloseHandle(pi.hThread);
+ }
+ return svcUpdateProcessStarted;
+}
+
+#endif
+
+/**
+ * Executes a maintenance service command
+ *
+ * @param argc The total number of arguments in argv
+ * @param argv An array of null terminated strings to pass to the service,
+ * @return ERROR_SUCCESS if the service command was started.
+ * Less than 16000, a windows system error code from StartServiceW
+ * More than 20000, 20000 + the last state of the service constant if
+ * the last state is something other than stopped.
+ * 17001 if the SCM could not be opened
+ * 17002 if the service could not be opened
+*/
+DWORD
+StartServiceCommand(int argc, LPCWSTR* argv)
+{
+ DWORD lastState = WaitForServiceStop(SVC_NAME, 5);
+ if (lastState != SERVICE_STOPPED)
+ {
+ return 20000 + lastState;
+ }
+
+ // Get a handle to the SCM database.
+ SC_HANDLE serviceManager = OpenSCManager(nullptr, nullptr,
+ SC_MANAGER_CONNECT |
+ SC_MANAGER_ENUMERATE_SERVICE);
+ if (!serviceManager)
+ {
+ return 17001;
+ }
+
+ // Get a handle to the service.
+ SC_HANDLE service = OpenServiceW(serviceManager,
+ SVC_NAME,
+ SERVICE_START);
+ if (!service)
+ {
+ CloseServiceHandle(serviceManager);
+ return 17002;
+ }
+
+ // Wait at most 5 seconds trying to start the service in case of errors
+ // like ERROR_SERVICE_DATABASE_LOCKED or ERROR_SERVICE_REQUEST_TIMEOUT.
+ const DWORD maxWaitMS = 5000;
+ DWORD currentWaitMS = 0;
+ DWORD lastError = ERROR_SUCCESS;
+ while (currentWaitMS < maxWaitMS)
+ {
+ BOOL result = StartServiceW(service, argc, argv);
+ if (result)
+ {
+ lastError = ERROR_SUCCESS;
+ break;
+ }
+ else
+ {
+ lastError = GetLastError();
+ }
+ Sleep(100);
+ currentWaitMS += 100;
+ }
+ CloseServiceHandle(service);
+ CloseServiceHandle(serviceManager);
+ return lastError;
+}
+
+#ifndef ONLY_SERVICE_LAUNCHING
+
+/**
+ * Launch a service initiated action for a software update with the
+ * specified arguments.
+ *
+ * @param exePath The path of the executable to run
+ * @param argc The total number of arguments in argv
+ * @param argv An array of null terminated strings to pass to the exePath,
+ * argv[0] must be the path to the updater.exe
+ * @return ERROR_SUCCESS if successful
+ */
+DWORD
+LaunchServiceSoftwareUpdateCommand(int argc, LPCWSTR* argv)
+{
+ // The service command is the same as the updater.exe command line except
+ // it has 2 extra args: 1) The Path to updater.exe, and 2) the command
+ // being executed which is "software-update"
+ LPCWSTR *updaterServiceArgv = new LPCWSTR[argc + 2];
+ updaterServiceArgv[0] = L"MozillaMaintenance";
+ updaterServiceArgv[1] = L"software-update";
+
+ for (int i = 0; i < argc; ++i)
+ {
+ updaterServiceArgv[i + 2] = argv[i];
+ }
+
+ // Execute the service command by starting the service with
+ // the passed in arguments.
+ DWORD ret = StartServiceCommand(argc + 2, updaterServiceArgv);
+ delete[] updaterServiceArgv;
+ return ret;
+}
+
+/**
+ * Joins a base directory path with a filename.
+ *
+ * @param base The base directory path of size MAX_PATH + 1
+ * @param extra The filename to append
+ * @return TRUE if the file name was successful appended to base
+ */
+BOOL
+PathAppendSafe(LPWSTR base, LPCWSTR extra)
+{
+ if (wcslen(base) + wcslen(extra) >= MAX_PATH)
+ {
+ return FALSE;
+ }
+
+ return PathAppendW(base, extra);
+}
+
+/**
+ * Sets update.status to pending so that the next startup will not use
+ * the service and instead will attempt an update the with a UAC prompt.
+ *
+ * @param updateDirPath The path of the update directory
+ * @return TRUE if successful
+ */
+BOOL
+WriteStatusPending(LPCWSTR updateDirPath)
+{
+ WCHAR updateStatusFilePath[MAX_PATH + 1] = { L'\0' };
+ wcsncpy(updateStatusFilePath, updateDirPath, MAX_PATH);
+ if (!PathAppendSafe(updateStatusFilePath, L"update.status"))
+ {
+ return FALSE;
+ }
+
+ const char pending[] = "pending";
+ HANDLE statusFile = CreateFileW(updateStatusFilePath, GENERIC_WRITE, 0,
+ nullptr, CREATE_ALWAYS, 0, nullptr);
+ if (statusFile == INVALID_HANDLE_VALUE)
+ {
+ return FALSE;
+ }
+
+ DWORD wrote;
+ BOOL ok = WriteFile(statusFile, pending,
+ sizeof(pending) - 1, &wrote, nullptr);
+ CloseHandle(statusFile);
+ return ok && (wrote == sizeof(pending) - 1);
+}
+
+/**
+ * Sets update.status to a specific failure code
+ *
+ * @param updateDirPath The path of the update directory
+ * @return TRUE if successful
+ */
+BOOL
+WriteStatusFailure(LPCWSTR updateDirPath, int errorCode)
+{
+ WCHAR updateStatusFilePath[MAX_PATH + 1] = { L'\0' };
+ wcsncpy(updateStatusFilePath, updateDirPath, MAX_PATH);
+ if (!PathAppendSafe(updateStatusFilePath, L"update.status"))
+ {
+ return FALSE;
+ }
+
+ HANDLE statusFile = CreateFileW(updateStatusFilePath, GENERIC_WRITE, 0,
+ nullptr, CREATE_ALWAYS, 0, nullptr);
+ if (statusFile == INVALID_HANDLE_VALUE)
+ {
+ return FALSE;
+ }
+ char failure[32];
+ sprintf(failure, "failed: %d", errorCode);
+
+ DWORD toWrite = strlen(failure);
+ DWORD wrote;
+ BOOL ok = WriteFile(statusFile, failure,
+ toWrite, &wrote, nullptr);
+ CloseHandle(statusFile);
+ return ok && wrote == toWrite;
+}
+
+#endif
+
+/**
+ * Waits for a service to enter a stopped state.
+ * This function does not stop the service, it just blocks until the service
+ * is stopped.
+ *
+ * @param serviceName The service to wait for.
+ * @param maxWaitSeconds The maximum number of seconds to wait
+ * @return state of the service after a timeout or when stopped.
+ * A value of 255 is returned for an error. Typical values are:
+ * SERVICE_STOPPED 0x00000001
+ * SERVICE_START_PENDING 0x00000002
+ * SERVICE_STOP_PENDING 0x00000003
+ * SERVICE_RUNNING 0x00000004
+ * SERVICE_CONTINUE_PENDING 0x00000005
+ * SERVICE_PAUSE_PENDING 0x00000006
+ * SERVICE_PAUSED 0x00000007
+ * last status not set 0x000000CF
+ * Could no query status 0x000000DF
+ * Could not open service, access denied 0x000000EB
+ * Could not open service, invalid handle 0x000000EC
+ * Could not open service, invalid name 0x000000ED
+ * Could not open service, does not exist 0x000000EE
+ * Could not open service, other error 0x000000EF
+ * Could not open SCM, access denied 0x000000FD
+ * Could not open SCM, database does not exist 0x000000FE;
+ * Could not open SCM, other error 0x000000FF;
+ * Note: The strange choice of error codes above SERVICE_PAUSED are chosen
+ * in case Windows comes out with other service stats higher than 7, they
+ * would likely call it 8 and above. JS code that uses this in TestAUSHelper
+ * only handles values up to 255 so that's why we don't use GetLastError
+ * directly.
+ */
+DWORD
+WaitForServiceStop(LPCWSTR serviceName, DWORD maxWaitSeconds)
+{
+ // 0x000000CF is defined above to be not set
+ DWORD lastServiceState = 0x000000CF;
+
+ // Get a handle to the SCM database.
+ SC_HANDLE serviceManager = OpenSCManager(nullptr, nullptr,
+ SC_MANAGER_CONNECT |
+ SC_MANAGER_ENUMERATE_SERVICE);
+ if (!serviceManager)
+ {
+ DWORD lastError = GetLastError();
+ switch (lastError)
+ {
+ case ERROR_ACCESS_DENIED:
+ return 0x000000FD;
+ case ERROR_DATABASE_DOES_NOT_EXIST:
+ return 0x000000FE;
+ default:
+ return 0x000000FF;
+ }
+ }
+
+ // Get a handle to the service.
+ SC_HANDLE service = OpenServiceW(serviceManager,
+ serviceName,
+ SERVICE_QUERY_STATUS);
+ if (!service)
+ {
+ DWORD lastError = GetLastError();
+ CloseServiceHandle(serviceManager);
+ switch (lastError)
+ {
+ case ERROR_ACCESS_DENIED:
+ return 0x000000EB;
+ case ERROR_INVALID_HANDLE:
+ return 0x000000EC;
+ case ERROR_INVALID_NAME:
+ return 0x000000ED;
+ case ERROR_SERVICE_DOES_NOT_EXIST:
+ return 0x000000EE;
+ default:
+ return 0x000000EF;
+ }
+ }
+
+ DWORD currentWaitMS = 0;
+ SERVICE_STATUS_PROCESS ssp;
+ ssp.dwCurrentState = lastServiceState;
+ while (currentWaitMS < maxWaitSeconds * 1000)
+ {
+ DWORD bytesNeeded;
+ if (!QueryServiceStatusEx(service, SC_STATUS_PROCESS_INFO, (LPBYTE)&ssp,
+ sizeof(SERVICE_STATUS_PROCESS), &bytesNeeded))
+ {
+ DWORD lastError = GetLastError();
+ switch (lastError)
+ {
+ case ERROR_INVALID_HANDLE:
+ ssp.dwCurrentState = 0x000000D9;
+ break;
+ case ERROR_ACCESS_DENIED:
+ ssp.dwCurrentState = 0x000000DA;
+ break;
+ case ERROR_INSUFFICIENT_BUFFER:
+ ssp.dwCurrentState = 0x000000DB;
+ break;
+ case ERROR_INVALID_PARAMETER:
+ ssp.dwCurrentState = 0x000000DC;
+ break;
+ case ERROR_INVALID_LEVEL:
+ ssp.dwCurrentState = 0x000000DD;
+ break;
+ case ERROR_SHUTDOWN_IN_PROGRESS:
+ ssp.dwCurrentState = 0x000000DE;
+ break;
+ // These 3 errors can occur when the service is not yet stopped but
+ // it is stopping.
+ case ERROR_INVALID_SERVICE_CONTROL:
+ case ERROR_SERVICE_CANNOT_ACCEPT_CTRL:
+ case ERROR_SERVICE_NOT_ACTIVE:
+ currentWaitMS += 50;
+ Sleep(50);
+ continue;
+ default:
+ ssp.dwCurrentState = 0x000000DF;
+ }
+
+ // We couldn't query the status so just break out
+ break;
+ }
+
+ // The service is already in use.
+ if (ssp.dwCurrentState == SERVICE_STOPPED)
+ {
+ break;
+ }
+ currentWaitMS += 50;
+ Sleep(50);
+ }
+
+ lastServiceState = ssp.dwCurrentState;
+ CloseServiceHandle(service);
+ CloseServiceHandle(serviceManager);
+ return lastServiceState;
+}
+
+#ifndef ONLY_SERVICE_LAUNCHING
+
+/**
+ * Determines if there is at least one process running for the specified
+ * application. A match will be found across any session for any user.
+ *
+ * @param process The process to check for existence
+ * @return ERROR_NOT_FOUND if the process was not found
+ * ERROR_SUCCESS if the process was found and there were no errors
+ * Other Win32 system error code for other errors
+**/
+DWORD
+IsProcessRunning(LPCWSTR filename)
+{
+ // Take a snapshot of all processes in the system.
+ HANDLE snapshot = CreateToolhelp32Snapshot(TH32CS_SNAPPROCESS, 0);
+ if (INVALID_HANDLE_VALUE == snapshot)
+ {
+ return GetLastError();
+ }
+
+ PROCESSENTRY32W processEntry;
+ processEntry.dwSize = sizeof(PROCESSENTRY32W);
+ if (!Process32FirstW(snapshot, &processEntry))
+ {
+ DWORD lastError = GetLastError();
+ CloseHandle(snapshot);
+ return lastError;
+ }
+
+ do
+ {
+ if (wcsicmp(filename, processEntry.szExeFile) == 0)
+ {
+ CloseHandle(snapshot);
+ return ERROR_SUCCESS;
+ }
+ }
+ while (Process32NextW(snapshot, &processEntry));
+ CloseHandle(snapshot);
+ return ERROR_NOT_FOUND;
+}
+
+/**
+ * Waits for the specified application to exit.
+ *
+ * @param filename The application to wait for.
+ * @param maxSeconds The maximum amount of seconds to wait for all
+ * instances of the application to exit.
+ * @return ERROR_SUCCESS if no instances of the application exist
+ * WAIT_TIMEOUT if the process is still running after maxSeconds.
+ * Any other Win32 system error code.
+*/
+DWORD
+WaitForProcessExit(LPCWSTR filename, DWORD maxSeconds)
+{
+ DWORD applicationRunningError = WAIT_TIMEOUT;
+ for (DWORD i = 0; i < maxSeconds; i++)
+ {
+ applicationRunningError = IsProcessRunning(filename);
+ if (ERROR_NOT_FOUND == applicationRunningError)
+ {
+ return ERROR_SUCCESS;
+ }
+ Sleep(1000);
+ }
+
+ if (ERROR_SUCCESS == applicationRunningError)
+ {
+ return WAIT_TIMEOUT;
+ }
+
+ return applicationRunningError;
+}
+
+/**
+ * Determines if the fallback key exists or not
+ *
+ * @return TRUE if the fallback key exists and there was no error checking
+*/
+BOOL
+DoesFallbackKeyExist()
+{
+ HKEY testOnlyFallbackKey;
+ if (RegOpenKeyExW(HKEY_LOCAL_MACHINE,
+ TEST_ONLY_FALLBACK_KEY_PATH, 0,
+ KEY_READ | KEY_WOW64_64KEY,
+ &testOnlyFallbackKey) != ERROR_SUCCESS)
+ {
+ return FALSE;
+ }
+
+ RegCloseKey(testOnlyFallbackKey);
+ return TRUE;
+}
+
+#endif
+
+/**
+ * Determines if the file system for the specified file handle is local
+ * @param file path to check the filesystem type for, must be at most MAX_PATH
+ * @param isLocal out parameter which will hold TRUE if the drive is local
+ * @return TRUE if the call succeeded
+*/
+BOOL
+IsLocalFile(LPCWSTR file, BOOL &isLocal)
+{
+ WCHAR rootPath[MAX_PATH + 1] = { L'\0' };
+ if (wcslen(file) > MAX_PATH)
+ {
+ return FALSE;
+ }
+
+ wcsncpy(rootPath, file, MAX_PATH);
+ PathStripToRootW(rootPath);
+ isLocal = GetDriveTypeW(rootPath) == DRIVE_FIXED;
+ return TRUE;
+}
+
+
+/**
+ * Determines the DWORD value of a registry key value
+ *
+ * @param key The base key to where the value name exists
+ * @param valueName The name of the value
+ * @param retValue Out parameter which will hold the value
+ * @return TRUE on success
+*/
+static BOOL
+GetDWORDValue(HKEY key, LPCWSTR valueName, DWORD &retValue)
+{
+ DWORD regDWORDValueSize = sizeof(DWORD);
+ LONG retCode = RegQueryValueExW(key, valueName, 0, nullptr,
+ reinterpret_cast<LPBYTE>(&retValue),
+ &regDWORDValueSize);
+ return ERROR_SUCCESS == retCode;
+}
+
+/**
+ * Determines if the system's elevation type allows
+ * unprompted elevation.
+ *
+ * @param isUnpromptedElevation Out parameter which specifies if unprompted
+ * elevation is allowed.
+ * @return TRUE if the user can actually elevate and the value was obtained
+ * successfully.
+*/
+BOOL
+IsUnpromptedElevation(BOOL &isUnpromptedElevation)
+{
+ if (!UACHelper::CanUserElevate())
+ {
+ return FALSE;
+ }
+
+ LPCWSTR UACBaseRegKey =
+ L"SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Policies\\System";
+ HKEY baseKey;
+ LONG retCode = RegOpenKeyExW(HKEY_LOCAL_MACHINE,
+ UACBaseRegKey, 0,
+ KEY_READ, &baseKey);
+ if (retCode != ERROR_SUCCESS)
+ {
+ return FALSE;
+ }
+
+ DWORD consent;
+ DWORD secureDesktop = 0;
+ BOOL success = GetDWORDValue(baseKey, L"ConsentPromptBehaviorAdmin",
+ consent);
+ success = success &&
+ GetDWORDValue(baseKey, L"PromptOnSecureDesktop", secureDesktop);
+ isUnpromptedElevation = !consent && !secureDesktop;
+
+ RegCloseKey(baseKey);
+ return success;
+}
+#endif