Adding upstream version 86.0.1.upstream/86.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 763 insertions, 0 deletions

diff --git a/toolkit/mozapps/update/common/updatehelper.cpp b/toolkit/mozapps/update/common/updatehelper.cpp
new file mode 100644
index 0000000000..b094d9eb75
--- /dev/null
+++ b/toolkit/mozapps/update/common/updatehelper.cpp
@@ -0,0 +1,763 @@
+/* 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/. */
+
+#include <windows.h>
+
+// Needed for CreateToolhelp32Snapshot
+#include <tlhelp32.h>
+
+#include <stdio.h>
+#include <direct.h>
+#include "shlobj.h"
+
+// Needed for PathAppendW
+#include <shlwapi.h>
+
+#include "updatehelper.h"
+#include "updateutils_win.h"
+
+#ifdef MOZ_MAINTENANCE_SERVICE
+#  include "mozilla/UniquePtr.h"
+#  include "pathhash.h"
+#  include "registrycertificates.h"
+#  include "uachelper.h"
+
+using mozilla::MakeUnique;
+using mozilla::UniquePtr;
+#endif
+
+BOOL PathGetSiblingFilePath(LPWSTR destinationBuffer, LPCWSTR siblingFilePath,
+                            LPCWSTR newFileName);
+
+/**
+ * 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 + 1);
+  if (!PathRemoveFileSpecW(destinationBuffer)) {
+    return FALSE;
+  }
+
+  return PathAppendSafe(destinationBuffer, newFileName);
+}
+
+/**
+ * Obtains the path of the secure directory used to write the status and log
+ * files for updates applied with an elevated updater or an updater that is
+ * launched using the maintenance service.
+ *
+ * Example
+ * Destination buffer value:
+ *   C:\Program Files (x86)\Mozilla Maintenance Service\UpdateLogs
+ *
+ * @param  outBuf
+ *         A buffer of size MAX_PATH + 1 to store the result.
+ * @return TRUE if successful
+ */
+BOOL GetSecureOutputDirectoryPath(LPWSTR outBuf) {
+  PWSTR progFilesX86;
+  if (FAILED(SHGetKnownFolderPath(FOLDERID_ProgramFilesX86, KF_FLAG_CREATE,
+                                  nullptr, &progFilesX86))) {
+    return FALSE;
+  }
+  if (wcslen(progFilesX86) > MAX_PATH) {
+    CoTaskMemFree(progFilesX86);
+    return FALSE;
+  }
+  wcsncpy(outBuf, progFilesX86, MAX_PATH + 1);
+  CoTaskMemFree(progFilesX86);
+
+  if (!PathAppendSafe(outBuf, L"Mozilla Maintenance Service")) {
+    return FALSE;
+  }
+
+  // Create the Maintenance Service directory in case it doesn't exist.
+  if (!CreateDirectoryW(outBuf, nullptr) &&
+      GetLastError() != ERROR_ALREADY_EXISTS) {
+    return FALSE;
+  }
+
+  if (!PathAppendSafe(outBuf, L"UpdateLogs")) {
+    return FALSE;
+  }
+
+  // Create the secure update output directory in case it doesn't exist.
+  if (!CreateDirectoryW(outBuf, nullptr) &&
+      GetLastError() != ERROR_ALREADY_EXISTS) {
+    return FALSE;
+  }
+
+  return TRUE;
+}
+
+/**
+ * Obtains the name of the update output file using the update patch directory
+ * path and file extension (must include the '.' separator) passed to this
+ * function.
+ *
+ * Example
+ * Patch directory path parameter:
+ *   C:\ProgramData\Mozilla\updates\0123456789ABCDEF\updates\0
+ * File extension parameter:
+ *   .status
+ * Destination buffer value:
+ *   0123456789ABCDEF.status
+ *
+ * @param  patchDirPath
+ *         The path to the update patch directory.
+ * @param  fileExt
+ *         The file extension for the file including the '.' separator.
+ * @param  outBuf
+ *         A buffer of size MAX_PATH + 1 to store the result.
+ * @return TRUE if successful
+ */
+BOOL GetSecureOutputFileName(LPCWSTR patchDirPath, LPCWSTR fileExt,
+                             LPWSTR outBuf) {
+  size_t fullPathLen = wcslen(patchDirPath);
+  if (fullPathLen > MAX_PATH) {
+    return FALSE;
+  }
+
+  size_t relPathLen = wcslen(PATCH_DIR_PATH);
+  if (relPathLen > fullPathLen) {
+    return FALSE;
+  }
+
+  // The patch directory path must end with updates\0 for updates applied with
+  // an elevated updater or an updater that is launched using the maintenance
+  // service.
+  if (_wcsnicmp(patchDirPath + fullPathLen - relPathLen, PATCH_DIR_PATH,
+                relPathLen) != 0) {
+    return FALSE;
+  }
+
+  wcsncpy(outBuf, patchDirPath, MAX_PATH + 1);
+  if (!PathRemoveFileSpecW(outBuf)) {
+    return FALSE;
+  }
+
+  if (!PathRemoveFileSpecW(outBuf)) {
+    return FALSE;
+  }
+
+  PathStripPathW(outBuf);
+
+  size_t outBufLen = wcslen(outBuf);
+  size_t fileExtLen = wcslen(fileExt);
+  if (outBufLen + fileExtLen > MAX_PATH) {
+    return FALSE;
+  }
+
+  wcsncat(outBuf, fileExt, fileExtLen);
+
+  return TRUE;
+}
+
+/**
+ * Obtains the full path of the secure update output file using the update patch
+ * directory path and file extension (must include the '.' separator) passed to
+ * this function.
+ *
+ * Example
+ * Patch directory path parameter:
+ *   C:\ProgramData\Mozilla\updates\0123456789ABCDEF\updates\0
+ * File extension parameter:
+ *   .status
+ * Destination buffer value:
+ *   C:\Program Files (x86)\Mozilla Maintenance
+ *     Service\UpdateLogs\0123456789ABCDEF.status
+ *
+ * @param  patchDirPath
+ *         The path to the update patch directory.
+ * @param  fileExt
+ *         The file extension for the file including the '.' separator.
+ * @param  outBuf
+ *         A buffer of size MAX_PATH + 1 to store the result.
+ * @return TRUE if successful
+ */
+BOOL GetSecureOutputFilePath(LPCWSTR patchDirPath, LPCWSTR fileExt,
+                             LPWSTR outBuf) {
+  if (!GetSecureOutputDirectoryPath(outBuf)) {
+    return FALSE;
+  }
+
+  WCHAR statusFileName[MAX_PATH + 1] = {L'\0'};
+  if (!GetSecureOutputFileName(patchDirPath, fileExt, statusFileName)) {
+    return FALSE;
+  }
+
+  return PathAppendSafe(outBuf, statusFileName);
+}
+
+/**
+ * Writes a UUID to the ID file in the secure output directory. This is used by
+ * the unelevated updater to determine whether an existing update status file in
+ * the secure output directory has been updated.
+ *
+ * @param  patchDirPath
+ *         The path to the update patch directory.
+ * @return TRUE if successful
+ */
+BOOL WriteSecureIDFile(LPCWSTR patchDirPath) {
+  WCHAR uuidString[MAX_PATH + 1] = {L'\0'};
+  if (!GetUUIDString(uuidString)) {
+    return FALSE;
+  }
+
+  WCHAR idFilePath[MAX_PATH + 1] = {L'\0'};
+  if (!GetSecureOutputFilePath(patchDirPath, L".id", idFilePath)) {
+    return FALSE;
+  }
+
+  FILE* idFile = _wfopen(idFilePath, L"wb+");
+  if (idFile == nullptr) {
+    return FALSE;
+  }
+
+  if (fprintf(idFile, "%ls\n", uuidString) == -1) {
+    fclose(idFile);
+    return FALSE;
+  }
+
+  fclose(idFile);
+
+  return TRUE;
+}
+
+/**
+ * Removes the update status and log files from the secure output directory.
+ *
+ * @param  patchDirPath
+ *         The path to the update patch directory.
+ */
+void RemoveSecureOutputFiles(LPCWSTR patchDirPath) {
+  WCHAR filePath[MAX_PATH + 1] = {L'\0'};
+  if (GetSecureOutputFilePath(patchDirPath, L".id", filePath)) {
+    (void)_wremove(filePath);
+  }
+  if (GetSecureOutputFilePath(patchDirPath, L".status", filePath)) {
+    (void)_wremove(filePath);
+  }
+  if (GetSecureOutputFilePath(patchDirPath, L".log", filePath)) {
+    (void)_wremove(filePath);
+  }
+}
+
+#ifdef MOZ_MAINTENANCE_SERVICE
+/**
+ * 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.
+  UniquePtr<char[]> serviceConfigBuffer = MakeUnique<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;
+  }
+
+  if (wcslen(installDir) > MAX_PATH) {
+    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 maintenace service.
+  // This is a requirement for maintenance service upgrades.
+  if (!CopyFileW(newMaintServicePath, tmpService, FALSE)) {
+    return FALSE;
+  }
+
+  // Check that the copied file's certificate matches the expected name and
+  // issuer stored in the registry for this installation and that the
+  // certificate is trusted by the system's certificate store.
+  if (!DoesBinaryMatchAllowedCertificates(installDir, tmpService)) {
+    DeleteFileW(tmpService);
+    return FALSE;
+  }
+
+  // Start the upgrade comparison process
+  STARTUPINFOW si = {0};
+  si.cb = sizeof(STARTUPINFOW);
+  // No particular desktop because no UI
+  si.lpDesktop = const_cast<LPWSTR>(L"");  // -Wwritable-strings
+  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;
+}
+
+/**
+ * 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;
+}
+
+/**
+ * Launch a service initiated action for a software update with the
+ * specified arguments.
+ *
+ * @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 4 extra args:
+  // 0) The name of the service, automatically added by Windows
+  // 1) "MozillaMaintenance" (I think this is redundant with 0)
+  // 2) The command being executed, which is "software-update"
+  // 3) The path to updater.exe (from argv[0])
+  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;
+}
+
+/**
+ * Writes a specific failure code for the update status to a file in the secure
+ * output directory. The status file's name without the '.' separator and
+ * extension is the same as the update directory name.
+ *
+ * @param  patchDirPath
+ *         The path of the update patch directory.
+ * @param  errorCode
+ *         Error code to set
+ * @return TRUE if successful
+ */
+BOOL WriteStatusFailure(LPCWSTR patchDirPath, int errorCode) {
+  WCHAR statusFilePath[MAX_PATH + 1] = {L'\0'};
+  if (!GetSecureOutputFilePath(patchDirPath, L".status", statusFilePath)) {
+    return FALSE;
+  }
+
+  HANDLE hStatusFile = CreateFileW(statusFilePath, GENERIC_WRITE, 0, nullptr,
+                                   CREATE_ALWAYS, 0, nullptr);
+  if (hStatusFile == INVALID_HANDLE_VALUE) {
+    return FALSE;
+  }
+
+  char failure[32];
+  sprintf(failure, "failed: %d", errorCode);
+  DWORD toWrite = strlen(failure);
+  DWORD wrote;
+  BOOL ok = WriteFile(hStatusFile, failure, toWrite, &wrote, nullptr);
+  CloseHandle(hStatusFile);
+
+  if (!ok || wrote != toWrite) {
+    return FALSE;
+  }
+
+  return TRUE;
+}
+
+/**
+ * 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;
+}
+#endif
+
+/**
+ * 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 existance
+ * @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++) {
+    DWORD applicationRunningError = IsProcessRunning(filename);
+    if (ERROR_NOT_FOUND == applicationRunningError) {
+      return ERROR_SUCCESS;
+    }
+    Sleep(1000);
+  }
+
+  if (ERROR_SUCCESS == applicationRunningError) {
+    return WAIT_TIMEOUT;
+  }
+
+  return applicationRunningError;
+}
+
+#ifdef MOZ_MAINTENANCE_SERVICE
+/**
+ *  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;
+}
+
+/**
+ * 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 the system's elevation type allows
+ * unprmopted 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, secureDesktop;
+  BOOL success = GetDWORDValue(baseKey, L"ConsentPromptBehaviorAdmin", consent);
+  success = success &&
+            GetDWORDValue(baseKey, L"PromptOnSecureDesktop", secureDesktop);
+
+  RegCloseKey(baseKey);
+  if (success) {
+    isUnpromptedElevation = !consent && !secureDesktop;
+  }
+
+  return success;
+}
+#endif