Adding upstream version 124.0.1.upstream/124.0.1

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

20 files changed, 3094 insertions, 0 deletions

diff --git a/security/sandbox/win/SandboxInitialization.cpp b/security/sandbox/win/SandboxInitialization.cpp
new file mode 100644
index 0000000000..8ba8b4e69a
--- /dev/null
+++ b/security/sandbox/win/SandboxInitialization.cpp
@@ -0,0 +1,202 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* 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 "SandboxInitialization.h"
+
+#include "base/memory/ref_counted.h"
+#include "nsWindowsDllInterceptor.h"
+#include "sandbox/win/src/process_mitigations.h"
+#include "sandbox/win/src/sandbox_factory.h"
+#include "mozilla/DebugOnly.h"
+#include "mozilla/WindowsProcessMitigations.h"
+
+namespace mozilla {
+namespace sandboxing {
+
+typedef BOOL(WINAPI* CloseHandle_func)(HANDLE hObject);
+static WindowsDllInterceptor::FuncHookType<CloseHandle_func> stub_CloseHandle;
+
+typedef BOOL(WINAPI* DuplicateHandle_func)(
+    HANDLE hSourceProcessHandle, HANDLE hSourceHandle,
+    HANDLE hTargetProcessHandle, LPHANDLE lpTargetHandle, DWORD dwDesiredAccess,
+    BOOL bInheritHandle, DWORD dwOptions);
+static WindowsDllInterceptor::FuncHookType<DuplicateHandle_func>
+    stub_DuplicateHandle;
+
+static BOOL WINAPI patched_CloseHandle(HANDLE hObject) {
+  // Check all handles being closed against the sandbox's tracked handles.
+  base::win::OnHandleBeingClosed(hObject);
+  return stub_CloseHandle(hObject);
+}
+
+static BOOL WINAPI patched_DuplicateHandle(
+    HANDLE hSourceProcessHandle, HANDLE hSourceHandle,
+    HANDLE hTargetProcessHandle, LPHANDLE lpTargetHandle, DWORD dwDesiredAccess,
+    BOOL bInheritHandle, DWORD dwOptions) {
+  // If closing a source handle from our process check it against the sandbox's
+  // tracked handles.
+  if ((dwOptions & DUPLICATE_CLOSE_SOURCE) &&
+      (GetProcessId(hSourceProcessHandle) == ::GetCurrentProcessId())) {
+    base::win::OnHandleBeingClosed(hSourceHandle);
+  }
+
+  return stub_DuplicateHandle(hSourceProcessHandle, hSourceHandle,
+                              hTargetProcessHandle, lpTargetHandle,
+                              dwDesiredAccess, bInheritHandle, dwOptions);
+}
+
+typedef BOOL(WINAPI* ApiSetQueryApiSetPresence_func)(PCUNICODE_STRING,
+                                                     PBOOLEAN);
+static WindowsDllInterceptor::FuncHookType<ApiSetQueryApiSetPresence_func>
+    stub_ApiSetQueryApiSetPresence;
+
+static const WCHAR gApiSetNtUserWindowStation[] =
+    L"ext-ms-win-ntuser-windowstation-l1-1-0";
+
+static BOOL WINAPI patched_ApiSetQueryApiSetPresence(
+    PCUNICODE_STRING aNamespace, PBOOLEAN aPresent) {
+  if (aNamespace && aPresent &&
+      !wcsncmp(aNamespace->Buffer, gApiSetNtUserWindowStation,
+               aNamespace->Length / sizeof(WCHAR))) {
+    *aPresent = FALSE;
+    return TRUE;
+  }
+
+  return stub_ApiSetQueryApiSetPresence(aNamespace, aPresent);
+}
+
+static WindowsDllInterceptor Kernel32Intercept;
+static WindowsDllInterceptor gApiQueryIntercept;
+
+static bool EnableHandleCloseMonitoring() {
+  Kernel32Intercept.Init("kernel32.dll");
+  bool hooked = stub_CloseHandle.Set(Kernel32Intercept, "CloseHandle",
+                                     &patched_CloseHandle);
+  if (!hooked) {
+    return false;
+  }
+
+  hooked = stub_DuplicateHandle.Set(Kernel32Intercept, "DuplicateHandle",
+                                    &patched_DuplicateHandle);
+  if (!hooked) {
+    return false;
+  }
+
+  return true;
+}
+
+/**
+ * There is a bug in COM that causes its initialization to fail when user32.dll
+ * is loaded but Win32k lockdown is enabled. COM uses ApiSetQueryApiSetPresence
+ * to make this check. When we are under Win32k lockdown, we hook
+ * ApiSetQueryApiSetPresence and force it to tell the caller that the DLL of
+ * interest is not present.
+ */
+static void EnableApiQueryInterception() {
+  if (!IsWin32kLockedDown()) {
+    return;
+  }
+
+  gApiQueryIntercept.Init(L"Api-ms-win-core-apiquery-l1-1-0.dll");
+  DebugOnly<bool> hookSetOk = stub_ApiSetQueryApiSetPresence.Set(
+      gApiQueryIntercept, "ApiSetQueryApiSetPresence",
+      &patched_ApiSetQueryApiSetPresence);
+  MOZ_ASSERT(hookSetOk);
+}
+
+static bool ShouldDisableHandleVerifier() {
+#if defined(_X86_) && (defined(EARLY_BETA_OR_EARLIER) || defined(DEBUG))
+  // Chromium only has the verifier enabled for 32-bit and our close monitoring
+  // hooks cause debug assertions for 64-bit anyway.
+  // For x86 keep the verifier enabled by default only for Nightly or debug.
+  return false;
+#else
+  return !getenv("MOZ_ENABLE_HANDLE_VERIFIER");
+#endif
+}
+
+static void InitializeHandleVerifier() {
+  // Disable the handle verifier if we don't want it or can't enable the close
+  // monitoring hooks.
+  if (ShouldDisableHandleVerifier() || !EnableHandleCloseMonitoring()) {
+    base::win::DisableHandleVerifier();
+  }
+}
+
+static sandbox::TargetServices* InitializeTargetServices() {
+  // This might disable the verifier, so we want to do it before it is used.
+  InitializeHandleVerifier();
+
+  EnableApiQueryInterception();
+
+  sandbox::TargetServices* targetServices =
+      sandbox::SandboxFactory::GetTargetServices();
+  if (!targetServices) {
+    return nullptr;
+  }
+
+  if (targetServices->Init() != sandbox::SBOX_ALL_OK) {
+    return nullptr;
+  }
+
+  return targetServices;
+}
+
+sandbox::TargetServices* GetInitializedTargetServices() {
+  static sandbox::TargetServices* sInitializedTargetServices =
+      InitializeTargetServices();
+
+  return sInitializedTargetServices;
+}
+
+void LowerSandbox() { GetInitializedTargetServices()->LowerToken(); }
+
+static sandbox::BrokerServices* InitializeBrokerServices() {
+  // This might disable the verifier, so we want to do it before it is used.
+  InitializeHandleVerifier();
+
+  sandbox::BrokerServices* brokerServices =
+      sandbox::SandboxFactory::GetBrokerServices();
+  if (!brokerServices) {
+    return nullptr;
+  }
+
+  if (brokerServices->Init() != sandbox::SBOX_ALL_OK) {
+    return nullptr;
+  }
+
+  // Comment below copied from Chromium code.
+  // Precreate the desktop and window station used by the renderers.
+  // IMPORTANT: This piece of code needs to run as early as possible in the
+  // process because it will initialize the sandbox broker, which requires
+  // the process to swap its window station. During this time all the UI
+  // will be broken. This has to run before threads and windows are created.
+  scoped_refptr<sandbox::TargetPolicy> policy = brokerServices->CreatePolicy();
+  policy->CreateAlternateDesktop(true);
+
+  // Ensure the relevant mitigations are enforced.
+  mozilla::sandboxing::ApplyParentProcessMitigations();
+
+  return brokerServices;
+}
+
+sandbox::BrokerServices* GetInitializedBrokerServices() {
+  static sandbox::BrokerServices* sInitializedBrokerServices =
+      InitializeBrokerServices();
+
+  return sInitializedBrokerServices;
+}
+
+void ApplyParentProcessMitigations() {
+  // The main reason for this call is for the token hardening, but chromium code
+  // also ensures DEP without ATL thunk so we do the same.
+  sandbox::ApplyProcessMitigationsToCurrentProcess(
+      sandbox::MITIGATION_DEP | sandbox::MITIGATION_DEP_NO_ATL_THUNK |
+      sandbox::MITIGATION_HARDEN_TOKEN_IL_POLICY);
+}
+
+}  // namespace sandboxing
+}  // namespace mozilla
diff --git a/security/sandbox/win/SandboxInitialization.h b/security/sandbox/win/SandboxInitialization.h
new file mode 100644
index 0000000000..1d49c0d899
--- /dev/null
+++ b/security/sandbox/win/SandboxInitialization.h
@@ -0,0 +1,52 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#ifndef mozilla_sandboxing_SandboxInitialization_h
+#define mozilla_sandboxing_SandboxInitialization_h
+
+namespace sandbox {
+class BrokerServices;
+class TargetServices;
+}  // namespace sandbox
+
+// Things that use this file will probably want access to the IsSandboxedProcess
+// function defined in one of the Chromium sandbox cc files.
+extern "C" bool IsSandboxedProcess();
+
+namespace mozilla {
+// Note the Chromium code just uses a bare sandbox namespace, which makes using
+// sandbox for our namespace painful.
+namespace sandboxing {
+
+/**
+ * Initializes (if required) and returns the Chromium sandbox TargetServices.
+ *
+ * @return the TargetServices or null if the creation or initialization failed.
+ */
+sandbox::TargetServices* GetInitializedTargetServices();
+
+/**
+ * Lowers the permissions on the process sandbox.
+ * Provided because the GMP sandbox needs to be lowered from the executable.
+ */
+void LowerSandbox();
+
+/**
+ * Initializes (if required) and returns the Chromium sandbox BrokerServices.
+ *
+ * @return the BrokerServices or null if the creation or initialization failed.
+ */
+sandbox::BrokerServices* GetInitializedBrokerServices();
+
+/**
+ * Apply mitigations for parent processes.
+ */
+void ApplyParentProcessMitigations();
+
+}  // namespace sandboxing
+}  // namespace mozilla
+
+#endif  // mozilla_sandboxing_SandboxInitialization_h
diff --git a/security/sandbox/win/src/remotesandboxbroker/PRemoteSandboxBroker.ipdl b/security/sandbox/win/src/remotesandboxbroker/PRemoteSandboxBroker.ipdl
new file mode 100644
index 0000000000..139380259f
--- /dev/null
+++ b/security/sandbox/win/src/remotesandboxbroker/PRemoteSandboxBroker.ipdl
@@ -0,0 +1,36 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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/. */
+
+using mozilla::dom::NativeThreadId from "mozilla/dom/NativeThreadId.h";
+
+namespace mozilla {
+
+struct EnvVar {
+  nsString name;
+  nsString value;
+};
+
+struct LaunchParameters {
+  nsString path;
+  nsString args;
+  EnvVar[] env;
+  uint32_t processType;
+  uint32_t sandboxLevel;
+  nsString[] allowedReadFiles;
+  uint64_t[] shareHandles;
+  bool enableLogging;
+};
+
+[NeedsOtherPid, NestedUpTo=inside_sync, ChildProc=RemoteSandboxBroker]
+sync protocol PRemoteSandboxBroker
+{
+parent:
+  async InitCrashReporter(NativeThreadId threadId);
+child:
+  [Nested=inside_sync] sync LaunchApp(LaunchParameters params)
+    returns (bool ok, uint64_t handle);
+};
+
+} // namespace mozilla
diff --git a/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerChild.cpp b/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerChild.cpp
new file mode 100644
index 0000000000..9d6b146d52
--- /dev/null
+++ b/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerChild.cpp
@@ -0,0 +1,87 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 https://mozilla.org/MPL/2.0/. */
+
+#include "RemoteSandboxBrokerChild.h"
+#include "chrome/common/ipc_channel.h"
+#include "mozilla/ipc/CrashReporterClient.h"
+#include "nsDebugImpl.h"
+#include "mozilla/ipc/CrashReporterClient.h"
+#include "RemoteSandboxBrokerProcessChild.h"
+
+using namespace mozilla::ipc;
+
+namespace mozilla {
+
+RemoteSandboxBrokerChild::RemoteSandboxBrokerChild() {
+  nsDebugImpl::SetMultiprocessMode("RemoteSandboxBroker");
+}
+
+RemoteSandboxBrokerChild::~RemoteSandboxBrokerChild() {}
+
+bool RemoteSandboxBrokerChild::Init(mozilla::ipc::UntypedEndpoint&& aEndpoint) {
+  if (NS_WARN_IF(!aEndpoint.Bind(this))) {
+    return false;
+  }
+  CrashReporterClient::InitSingleton(this);
+  return true;
+}
+
+void RemoteSandboxBrokerChild::ActorDestroy(ActorDestroyReason aWhy) {
+  if (AbnormalShutdown == aWhy) {
+    NS_WARNING("Abnormal shutdown of GMP process!");
+    ipc::ProcessChild::QuickExit();
+  }
+  CrashReporterClient::DestroySingleton();
+  XRE_ShutdownChildProcess();
+}
+
+mozilla::ipc::IPCResult RemoteSandboxBrokerChild::RecvLaunchApp(
+    LaunchParameters&& aParams, bool* aOutOk, uint64_t* aOutHandle) {
+  auto towstring = [](const nsString& s) {
+    return std::wstring(s.get(), s.Length());
+  };
+
+  base::EnvironmentMap envmap;
+  for (const EnvVar& env : aParams.env()) {
+    envmap[towstring(env.name())] = towstring(env.value());
+  }
+
+  if (!mSandboxBroker.SetSecurityLevelForGMPlugin(
+          AbstractSandboxBroker::SandboxLevel(aParams.sandboxLevel()),
+          /* aIsRemoteLaunch */ true)) {
+    *aOutOk = false;
+    return IPC_OK();
+  }
+
+  for (const auto& path : aParams.allowedReadFiles()) {
+    if (!mSandboxBroker.AllowReadFile(path.get())) {
+      *aOutOk = false;
+      return IPC_OK();
+    }
+  }
+
+  for (const auto& handle : aParams.shareHandles()) {
+    mSandboxBroker.AddHandleToShare(HANDLE(handle));
+  }
+
+  HANDLE p;
+  mozilla::Result<mozilla::Ok, LaunchError> err =
+      mSandboxBroker.LaunchApp(aParams.path().get(), aParams.args().get(),
+                               envmap, GeckoProcessType(aParams.processType()),
+                               aParams.enableLogging(), nullptr, (void**)&p);
+  *aOutOk = err.isOk();
+  if (*aOutOk) {
+    *aOutHandle = uint64_t(p);
+  }
+
+  for (const auto& handle : aParams.shareHandles()) {
+    CloseHandle(HANDLE(handle));
+  }
+
+  return IPC_OK();
+}
+
+}  // namespace mozilla
diff --git a/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerChild.h b/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerChild.h
new file mode 100644
index 0000000000..cc707609df
--- /dev/null
+++ b/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerChild.h
@@ -0,0 +1,35 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 https://mozilla.org/MPL/2.0/. */
+
+#ifndef RemoteSandboxBrokerChild_h_
+#define RemoteSandboxBrokerChild_h_
+
+#include "mozilla/PRemoteSandboxBrokerChild.h"
+#include "sandboxBroker.h"
+
+namespace mozilla {
+
+class RemoteSandboxBrokerChild : public PRemoteSandboxBrokerChild {
+  friend class PRemoteSandboxBrokerChild;
+
+ public:
+  NS_INLINE_DECL_REFCOUNTING(RemoteSandboxBrokerChild, override)
+
+  RemoteSandboxBrokerChild();
+  bool Init(mozilla::ipc::UntypedEndpoint&& aEndpoint);
+
+ private:
+  virtual ~RemoteSandboxBrokerChild();
+  mozilla::ipc::IPCResult RecvLaunchApp(LaunchParameters&& aParams,
+                                        bool* aOutOk, uint64_t* aOutHandle);
+
+  void ActorDestroy(ActorDestroyReason aWhy);
+  SandboxBroker mSandboxBroker;
+};
+
+}  // namespace mozilla
+
+#endif
diff --git a/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerParent.cpp b/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerParent.cpp
new file mode 100644
index 0000000000..7306f4f7bf
--- /dev/null
+++ b/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerParent.cpp
@@ -0,0 +1,83 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 https://mozilla.org/MPL/2.0/. */
+
+#include "RemoteSandboxBrokerParent.h"
+#include "RemoteSandboxBrokerProcessParent.h"
+#include "mozilla/Telemetry.h"
+#include <windows.h>
+
+namespace mozilla {
+
+RefPtr<GenericPromise> RemoteSandboxBrokerParent::Launch(
+    uint32_t aLaunchArch, const nsTArray<uint64_t>& aHandlesToShare,
+    nsISerialEventTarget* aThread) {
+  MOZ_ASSERT(!mProcess);
+  if (mProcess) {
+    // Don't re-init.
+    return GenericPromise::CreateAndReject(NS_ERROR_FAILURE, __func__);
+  }
+
+  mProcess = new RemoteSandboxBrokerProcessParent();
+#ifdef ALLOW_GECKO_CHILD_PROCESS_ARCH
+  mProcess->SetLaunchArchitecture(aLaunchArch);
+#endif
+  for (uint64_t handle : aHandlesToShare) {
+    mProcess->AddHandleToShare(HANDLE(handle));
+  }
+
+  auto resolve = [self = RefPtr{this}](base::ProcessHandle handle) {
+    self->mOpened = self->mProcess->TakeInitialEndpoint().Bind(self);
+    if (!self->mOpened) {
+      self->mProcess->Destroy();
+      self->mProcess = nullptr;
+      return GenericPromise::CreateAndReject(NS_ERROR_FAILURE, __func__);
+    }
+    return GenericPromise::CreateAndResolve(true, __func__);
+  };
+
+  auto reject = [self = RefPtr{this}]() {
+    NS_ERROR("failed to launch child in the parent");
+    if (self->mProcess) {
+      self->mProcess->Destroy();
+      self->mProcess = nullptr;
+    }
+    return GenericPromise::CreateAndReject(NS_ERROR_FAILURE, __func__);
+  };
+
+  return mProcess->AsyncLaunch()->Then(aThread, __func__, std::move(resolve),
+                                       std::move(reject));
+}
+
+bool RemoteSandboxBrokerParent::DuplicateFromLauncher(HANDLE aLauncherHandle,
+                                                      LPHANDLE aOurHandle) {
+  return ::DuplicateHandle(mProcess->GetChildProcessHandle(), aLauncherHandle,
+                           ::GetCurrentProcess(), aOurHandle, 0, false,
+                           DUPLICATE_SAME_ACCESS | DUPLICATE_CLOSE_SOURCE);
+}
+
+void RemoteSandboxBrokerParent::ActorDestroy(ActorDestroyReason aWhy) {
+  if (AbnormalShutdown == aWhy) {
+    Telemetry::Accumulate(Telemetry::SUBPROCESS_ABNORMAL_ABORT,
+                          nsDependentCString(XRE_GeckoProcessTypeToString(
+                              GeckoProcessType_RemoteSandboxBroker)),
+                          1);
+    GenerateCrashReport(OtherPid());
+  }
+  Shutdown();
+}
+
+void RemoteSandboxBrokerParent::Shutdown() {
+  if (mOpened) {
+    mOpened = false;
+    Close();
+  }
+  if (mProcess) {
+    mProcess->Destroy();
+    mProcess = nullptr;
+  }
+}
+
+}  // namespace mozilla
diff --git a/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerParent.h b/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerParent.h
new file mode 100644
index 0000000000..7645b68923
--- /dev/null
+++ b/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerParent.h
@@ -0,0 +1,48 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 https://mozilla.org/MPL/2.0/. */
+
+#ifndef RemoteSandboxBrokerParent_h_
+#define RemoteSandboxBrokerParent_h_
+
+#include "mozilla/PRemoteSandboxBrokerParent.h"
+#include "RemoteSandboxBrokerProcessParent.h"
+#include "mozilla/ipc/CrashReporterHelper.h"
+
+namespace mozilla {
+
+class RemoteSandboxBrokerParent
+    : public PRemoteSandboxBrokerParent,
+      public ipc::CrashReporterHelper<GeckoProcessType_RemoteSandboxBroker> {
+  friend class PRemoteSandboxBrokerParent;
+
+ public:
+  NS_INLINE_DECL_REFCOUNTING(RemoteSandboxBrokerParent, override)
+
+  bool DuplicateFromLauncher(HANDLE aLauncherHandle, LPHANDLE aOurHandle);
+
+  void Shutdown();
+
+  // Asynchronously launches the launcher process.
+  // Note: we rely on the caller to keep this instance alive
+  // until this promise resolves.
+  // aThread is the thread to use to resolve the promise on if needed.
+  RefPtr<GenericPromise> Launch(uint32_t aLaunchArch,
+                                const nsTArray<uint64_t>& aHandlesToShare,
+                                nsISerialEventTarget* aThread);
+
+ private:
+  ~RemoteSandboxBrokerParent() = default;
+
+  void ActorDestroy(ActorDestroyReason aWhy) override;
+
+  RemoteSandboxBrokerProcessParent* mProcess = nullptr;
+
+  bool mOpened = false;
+};
+
+}  // namespace mozilla
+
+#endif  // RemoteSandboxBrokerParent_h_
diff --git a/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerProcessChild.cpp b/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerProcessChild.cpp
new file mode 100644
index 0000000000..32e7d3b1f4
--- /dev/null
+++ b/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerProcessChild.cpp
@@ -0,0 +1,27 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 https://mozilla.org/MPL/2.0/. */
+
+#include "RemoteSandboxBrokerProcessChild.h"
+
+#include "mozilla/ipc/IOThreadChild.h"
+#include "mozilla/BackgroundHangMonitor.h"
+
+using mozilla::ipc::IOThreadChild;
+
+namespace mozilla {
+
+RemoteSandboxBrokerProcessChild::~RemoteSandboxBrokerProcessChild() {}
+
+bool RemoteSandboxBrokerProcessChild::Init(int aArgc, char* aArgv[]) {
+  BackgroundHangMonitor::Startup();
+  return mSandboxBrokerChild->Init(TakeInitialEndpoint());
+}
+
+void RemoteSandboxBrokerProcessChild::CleanUp() {
+  BackgroundHangMonitor::Shutdown();
+}
+
+}  // namespace mozilla
diff --git a/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerProcessChild.h b/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerProcessChild.h
new file mode 100644
index 0000000000..7b47f1e828
--- /dev/null
+++ b/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerProcessChild.h
@@ -0,0 +1,33 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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/. */
+
+#ifndef RemoteSandboxBrokerProcessChild_h_
+#define RemoteSandboxBrokerProcessChild_h_
+
+#include "mozilla/ipc/ProcessChild.h"
+#include "RemoteSandboxBrokerChild.h"
+
+namespace mozilla {
+
+class RemoteSandboxBrokerProcessChild final
+    : public mozilla::ipc::ProcessChild {
+ protected:
+  typedef mozilla::ipc::ProcessChild ProcessChild;
+
+ public:
+  using ProcessChild::ProcessChild;
+  ~RemoteSandboxBrokerProcessChild();
+
+  bool Init(int aArgc, char* aArgv[]) override;
+  void CleanUp() override;
+
+ private:
+  RefPtr<RemoteSandboxBrokerChild> mSandboxBrokerChild =
+      new RemoteSandboxBrokerChild;
+};
+
+}  // namespace mozilla
+
+#endif  // GMPProcessChild_h_
diff --git a/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerProcessParent.cpp b/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerProcessParent.cpp
new file mode 100644
index 0000000000..218753bb52
--- /dev/null
+++ b/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerProcessParent.cpp
@@ -0,0 +1,35 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 https://mozilla.org/MPL/2.0/. */
+
+#include "RemoteSandboxBrokerProcessParent.h"
+#include <windows.h>
+
+#include "mozilla/ipc/LaunchError.h"
+
+using mozilla::ipc::GeckoChildProcessHost;
+using mozilla::ipc::LaunchError;
+using mozilla::ipc::ProcessHandlePromise;
+
+namespace mozilla {
+
+RemoteSandboxBrokerProcessParent::RemoteSandboxBrokerProcessParent()
+    : GeckoChildProcessHost(GeckoProcessType_RemoteSandboxBroker) {
+  MOZ_COUNT_CTOR(RemoteSandboxBrokerProcessParent);
+}
+
+RemoteSandboxBrokerProcessParent::~RemoteSandboxBrokerProcessParent() {
+  MOZ_COUNT_DTOR(RemoteSandboxBrokerProcessParent);
+}
+
+RefPtr<ProcessHandlePromise> RemoteSandboxBrokerProcessParent::AsyncLaunch() {
+  if (!GeckoChildProcessHost::AsyncLaunch()) {
+    return ProcessHandlePromise::CreateAndReject(
+        LaunchError("RSBPP::AsyncLaunch"), __func__);
+  }
+  return WhenProcessHandleReady();
+}
+
+}  // namespace mozilla
diff --git a/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerProcessParent.h b/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerProcessParent.h
new file mode 100644
index 0000000000..fc22ff77b7
--- /dev/null
+++ b/security/sandbox/win/src/remotesandboxbroker/RemoteSandboxBrokerProcessParent.h
@@ -0,0 +1,39 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: sw=2 ts=4 et :
+ * 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/. */
+
+#ifndef RemoteSandboxBrokerProcessParent_h_
+#define RemoteSandboxBrokerProcessParent_h_
+
+#include "mozilla/Attributes.h"
+#include "base/basictypes.h"
+#include "base/file_path.h"
+#include "base/thread.h"
+#include "mozilla/ipc/GeckoChildProcessHost.h"
+
+class nsIRunnable;
+
+namespace mozilla {
+
+class RemoteSandboxBrokerProcessParent final
+    : public mozilla::ipc::GeckoChildProcessHost {
+ public:
+  RemoteSandboxBrokerProcessParent();
+
+  RefPtr<ipc::ProcessHandlePromise> AsyncLaunch();
+
+  bool CanShutdown() override { return true; }
+
+  using mozilla::ipc::GeckoChildProcessHost::GetChildProcessHandle;
+
+ private:
+  ~RemoteSandboxBrokerProcessParent();
+
+  DISALLOW_COPY_AND_ASSIGN(RemoteSandboxBrokerProcessParent);
+};
+
+}  // namespace mozilla
+
+#endif  // ifndef GMPProcessParent_h
diff --git a/security/sandbox/win/src/remotesandboxbroker/moz.build b/security/sandbox/win/src/remotesandboxbroker/moz.build
new file mode 100644
index 0000000000..6d661ace4c
--- /dev/null
+++ b/security/sandbox/win/src/remotesandboxbroker/moz.build
@@ -0,0 +1,30 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# 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/.
+
+SOURCES += [
+    "remoteSandboxBroker.cpp",
+    "RemoteSandboxBrokerChild.cpp",
+    "RemoteSandboxBrokerParent.cpp",
+    "RemoteSandboxBrokerProcessChild.cpp",
+    "RemoteSandboxBrokerProcessParent.cpp",
+]
+
+EXPORTS.mozilla += [
+    "remoteSandboxBroker.h",
+    "RemoteSandboxBrokerChild.h",
+    "RemoteSandboxBrokerParent.h",
+    "RemoteSandboxBrokerProcessChild.h",
+    "RemoteSandboxBrokerProcessParent.h",
+]
+
+for var in ("UNICODE", "_UNICODE"):
+    DEFINES[var] = True
+
+FINAL_LIBRARY = "xul"
+
+IPDL_SOURCES += ["PRemoteSandboxBroker.ipdl"]
+
+include("/ipc/chromium/chromium-config.mozbuild")
diff --git a/security/sandbox/win/src/remotesandboxbroker/remoteSandboxBroker.cpp b/security/sandbox/win/src/remotesandboxbroker/remoteSandboxBroker.cpp
new file mode 100644
index 0000000000..f898251d72
--- /dev/null
+++ b/security/sandbox/win/src/remotesandboxbroker/remoteSandboxBroker.cpp
@@ -0,0 +1,167 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 https://mozilla.org/MPL/2.0/. */
+
+#include "remoteSandboxBroker.h"
+
+#include "RemoteSandboxBrokerParent.h"
+#include "mozilla/SpinEventLoopUntil.h"
+#include "nsIThread.h"
+
+namespace mozilla {
+
+RemoteSandboxBroker::RemoteSandboxBroker(uint32_t aLaunchArch)
+    : mParent(new RemoteSandboxBrokerParent), mLaunchArch(aLaunchArch) {}
+
+RemoteSandboxBroker::~RemoteSandboxBroker() {
+  MOZ_ASSERT(
+      mShutdown,
+      "Shutdown must be called on RemoteSandboxBroker before destruction!");
+}
+
+void RemoteSandboxBroker::Shutdown() {
+  MOZ_ASSERT(!mShutdown, "Don't call Shutdown() twice!");
+  mShutdown = true;
+
+  if (!mIPCLaunchThread) {
+    // Can't have launched child process, nothing to shutdown.
+    return;
+  }
+
+  RefPtr<RemoteSandboxBroker> self = this;
+  mIPCLaunchThread->Dispatch(
+      NS_NewRunnableFunction("Remote Sandbox Launch", [self, this]() {
+        // Note: `self` here should be the last reference to this instance.
+        mParent->Shutdown();
+        mIPCLaunchThread = nullptr;
+      }));
+}
+
+Result<Ok, mozilla::ipc::LaunchError> RemoteSandboxBroker::LaunchApp(
+    const wchar_t* aPath, const wchar_t* aArguments,
+    base::EnvironmentMap& aEnvironment, GeckoProcessType aProcessType,
+    const bool aEnableLogging, const IMAGE_THUNK_DATA*, void** aProcessHandle) {
+  // Note: we expect to be called on the IPC launch thread from
+  // GeckoChildProcesHost while it's launching a child process. The IPC launch
+  // thread is a TaskQueue. We can't run a synchronous launch here as that
+  // blocks the calling thread while it dispatches a task to the IPC launch
+  // thread to spawn the process. Since our calling thread is the IPC launch
+  // thread, we'd then be deadlocked. So instead we do an async launch, and spin
+  // the event loop until the process launch succeeds.
+
+  // We should be on the IPC launch thread. We're shutdown on the IO thread,
+  // so save a ref to the IPC launch thread here, so we can close the channel
+  // on the IPC launch thread on shutdown.
+  mIPCLaunchThread = GetCurrentSerialEventTarget();
+
+  mParameters.path() = nsDependentString(aPath);
+  mParameters.args() = nsDependentString(aArguments);
+
+  auto toNsString = [](const std::wstring& s) {
+    return nsDependentString(s.c_str());
+  };
+  for (auto itr : aEnvironment) {
+    mParameters.env().AppendElement(
+        EnvVar(toNsString(itr.first), toNsString(itr.second)));
+  }
+
+  mParameters.processType() = uint32_t(aProcessType);
+  mParameters.enableLogging() = aEnableLogging;
+
+  enum Result { Pending, Succeeded, Failed };
+  Result res = Pending;
+  auto resolve = [&](bool ok) {
+    res = Succeeded;
+    return GenericPromise::CreateAndResolve(ok, __func__);
+  };
+
+  auto reject = [&](nsresult) {
+    res = Failed;
+    return GenericPromise::CreateAndReject(NS_ERROR_FAILURE, __func__);
+  };
+
+  // We need to wait on the current thread for the process to launch which will
+  // block the running IPC Launch taskqueue. We cannot use
+  // GetCurrentSerialEventTarget() (as this returns the currently running
+  // TaskQueue) to resolve our promise as it will be blocked until we return
+  // from this function.
+  nsCOMPtr<nsISerialEventTarget> target = NS_GetCurrentThread();
+  mParent->Launch(mLaunchArch, mParameters.shareHandles(), target)
+      ->Then(target, __func__, std::move(resolve), std::move(reject));
+
+  // Spin the event loop while the sandbox launcher process launches.
+  SpinEventLoopUntil("RemoteSandboxBroker::LaunchApp"_ns,
+                     [&]() { return res != Pending; });
+
+  if (res == Failed) {
+    return Err(mozilla::ipc::LaunchError("RSB::LaunchApp"));
+  }
+
+  uint64_t handle = 0;
+  bool ok = false;
+  bool rv = mParent->SendLaunchApp(std::move(mParameters), &ok, &handle) && ok;
+  mParameters.shareHandles().Clear();
+  if (!rv) {
+    mParent->Shutdown();
+    return Err(mozilla::ipc::LaunchError("RSB::SendLaunchApp"));
+  }
+
+  // Duplicate the handle of the child process that the launcher launched from
+  // the launcher process's space into this process' space.
+  HANDLE ourChildHandle = 0;
+  bool dh = mParent->DuplicateFromLauncher((HANDLE)handle, &ourChildHandle);
+  if (!dh) {
+    mParent->Shutdown();
+    return Err(mozilla::ipc::LaunchError("RSB::DuplicateFromLauncher"));
+  }
+
+  *aProcessHandle = (void**)(ourChildHandle);
+
+  return Ok();
+}
+
+bool RemoteSandboxBroker::SetSecurityLevelForGMPlugin(SandboxLevel aLevel,
+                                                      bool aIsRemoteLaunch) {
+  mParameters.sandboxLevel() = uint32_t(aLevel);
+  return true;
+}
+
+bool RemoteSandboxBroker::AllowReadFile(wchar_t const* aFile) {
+  mParameters.allowedReadFiles().AppendElement(nsDependentString(aFile));
+  return true;
+}
+
+void RemoteSandboxBroker::AddHandleToShare(HANDLE aHandle) {
+  mParameters.shareHandles().AppendElement(uint64_t(aHandle));
+}
+
+void RemoteSandboxBroker::SetSecurityLevelForContentProcess(
+    int32_t aSandboxLevel, bool aIsFileProcess) {
+  MOZ_CRASH(
+      "RemoteSandboxBroker::SetSecurityLevelForContentProcess not Implemented");
+}
+
+void RemoteSandboxBroker::SetSecurityLevelForGPUProcess(int32_t aSandboxLevel) {
+  MOZ_CRASH(
+      "RemoteSandboxBroker::SetSecurityLevelForGPUProcess not Implemented");
+}
+
+bool RemoteSandboxBroker::SetSecurityLevelForRDDProcess() {
+  MOZ_CRASH(
+      "RemoteSandboxBroker::SetSecurityLevelForRDDProcess not Implemented");
+}
+
+bool RemoteSandboxBroker::SetSecurityLevelForSocketProcess() {
+  MOZ_CRASH(
+      "RemoteSandboxBroker::SetSecurityLevelForSocketProcess not Implemented");
+}
+
+bool RemoteSandboxBroker::SetSecurityLevelForUtilityProcess(
+    mozilla::ipc::SandboxingKind aSandbox) {
+  MOZ_CRASH(
+      "RemoteSandboxBroker::SetSecurityLevelForUtilityProcess not Implemented");
+}
+
+}  // namespace mozilla
diff --git a/security/sandbox/win/src/remotesandboxbroker/remoteSandboxBroker.h b/security/sandbox/win/src/remotesandboxbroker/remoteSandboxBroker.h
new file mode 100644
index 0000000000..bb02470e0e
--- /dev/null
+++ b/security/sandbox/win/src/remotesandboxbroker/remoteSandboxBroker.h
@@ -0,0 +1,75 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 https://mozilla.org/MPL/2.0/. */
+
+#ifndef __REMOTE_SANDBOXBROKER_H__
+#define __REMOTE_SANDBOXBROKER_H__
+
+#include "sandboxBroker.h"
+#include "RemoteSandboxBrokerParent.h"
+
+#include "mozilla/Result.h"
+#include "mozilla/ipc/LaunchError.h"
+
+namespace mozilla {
+
+// To make sandboxing an x86 plugin-container process on Windows on ARM64,
+// we launch an x86 child process which in turn launches and sandboxes the x86
+// plugin-container child. This means the sandbox broker (in the remote
+// x86 sandbox launcher process) can be same-arch with the process that it's
+// sandboxing, which means all the sandbox's assumptions about things being
+// same arch still hold.
+class RemoteSandboxBroker : public AbstractSandboxBroker {
+ public:
+  explicit RemoteSandboxBroker(uint32_t aLaunchArch);
+
+  void Shutdown() override;
+
+  // Note: This should be called on the IPC launch thread, and this spins
+  // the event loop. So this means potentially another IPC launch could occur
+  // re-entrantly while calling this.
+  Result<Ok, mozilla::ipc::LaunchError> LaunchApp(
+      const wchar_t* aPath, const wchar_t* aArguments,
+      base::EnvironmentMap& aEnvironment, GeckoProcessType aProcessType,
+      const bool aEnableLogging, const IMAGE_THUNK_DATA*,
+      void** aProcessHandle) override;
+
+  // Security levels for different types of processes
+  void SetSecurityLevelForContentProcess(int32_t aSandboxLevel,
+                                         bool aIsFileProcess) override;
+  void SetSecurityLevelForGPUProcess(int32_t aSandboxLevel) override;
+  bool SetSecurityLevelForRDDProcess() override;
+  bool SetSecurityLevelForSocketProcess() override;
+  bool SetSecurityLevelForGMPlugin(SandboxLevel aLevel,
+                                   bool aIsRemoteLaunch = false) override;
+  bool SetSecurityLevelForUtilityProcess(
+      mozilla::ipc::SandboxingKind aSandbox) override;
+  bool AllowReadFile(wchar_t const* file) override;
+  void AddHandleToShare(HANDLE aHandle) override;
+
+  bool IsWin32kLockedDown() final { return false; };
+
+ private:
+  virtual ~RemoteSandboxBroker();
+
+  // Parameters that we use to launch the child process.
+  LaunchParameters mParameters;
+
+  RefPtr<RemoteSandboxBrokerParent> mParent;
+
+  // We bind the RemoteSandboxBrokerParent to the IPC launch thread.
+  // As such, we must close its channel on the same thread. So we save
+  // a reference to the IPC launch thread here.
+  nsCOMPtr<nsISerialEventTarget> mIPCLaunchThread;
+
+  // True if we've been shutdown.
+  bool mShutdown = false;
+
+  uint32_t mLaunchArch;
+};
+
+}  // namespace mozilla
+
+#endif  // __REMOTE_SANDBOXBROKER_H__
diff --git a/security/sandbox/win/src/sandboxbroker/moz.build b/security/sandbox/win/src/sandboxbroker/moz.build
new file mode 100644
index 0000000000..5eaf0de937
--- /dev/null
+++ b/security/sandbox/win/src/sandboxbroker/moz.build
@@ -0,0 +1,21 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# 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/.
+
+SOURCES += [
+    "sandboxBroker.cpp",
+]
+
+EXPORTS += [
+    "sandboxBroker.h",
+]
+
+for var in ("UNICODE", "_UNICODE"):
+    DEFINES[var] = True
+
+LOCAL_INCLUDES += ["/security/sandbox/chromium-shim"]
+LOCAL_INCLUDES += ["/security/sandbox/chromium"]
+
+FINAL_LIBRARY = "xul"
diff --git a/security/sandbox/win/src/sandboxbroker/sandboxBroker.cpp b/security/sandbox/win/src/sandboxbroker/sandboxBroker.cpp
new file mode 100644
index 0000000000..9b9ed97262
--- /dev/null
+++ b/security/sandbox/win/src/sandboxbroker/sandboxBroker.cpp
@@ -0,0 +1,1847 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#define MOZ_USE_LAUNCHER_ERROR
+
+#include "sandboxBroker.h"
+
+#include <aclapi.h>
+#include <shlobj.h>
+#include <string>
+
+#include "base/win/windows_version.h"
+#include "mozilla/Assertions.h"
+#include "mozilla/ClearOnShutdown.h"
+#include "mozilla/ImportDir.h"
+#include "mozilla/Logging.h"
+#include "mozilla/NSPRLogModulesParser.h"
+#include "mozilla/Omnijar.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/SandboxSettings.h"
+#include "mozilla/SHA1.h"
+#include "mozilla/StaticPrefs_network.h"
+#include "mozilla/StaticPrefs_security.h"
+#include "mozilla/StaticPrefs_widget.h"
+#include "mozilla/StaticPtr.h"
+#include "mozilla/UniquePtr.h"
+#include "mozilla/Telemetry.h"
+#include "mozilla/WinDllServices.h"
+#include "mozilla/WindowsVersion.h"
+#include "mozilla/WinHeaderOnlyUtils.h"
+#include "mozilla/ipc/LaunchError.h"
+#include "nsAppDirectoryServiceDefs.h"
+#include "nsCOMPtr.h"
+#include "nsDirectoryServiceDefs.h"
+#include "nsIFile.h"
+#include "nsIProperties.h"
+#include "nsIXULRuntime.h"
+#include "nsServiceManagerUtils.h"
+#include "nsString.h"
+#include "nsTArray.h"
+#include "nsTHashtable.h"
+#include "sandbox/win/src/app_container_profile.h"
+#include "sandbox/win/src/sandbox.h"
+#include "sandbox/win/src/security_level.h"
+#include "WinUtils.h"
+
+#define SANDBOX_SUCCEED_OR_CRASH(x)                                   \
+  do {                                                                \
+    sandbox::ResultCode result = (x);                                 \
+    MOZ_RELEASE_ASSERT(result == sandbox::SBOX_ALL_OK, #x " failed"); \
+  } while (0)
+
+namespace mozilla {
+
+constexpr wchar_t kLpacFirefoxInstallFiles[] = L"lpacFirefoxInstallFiles";
+
+sandbox::BrokerServices* sBrokerService = nullptr;
+
+// This is set to true in Initialize when our exe file name has a drive type of
+// DRIVE_REMOTE, so that we can tailor the sandbox policy as some settings break
+// fundamental things when running from a network drive. We default to false in
+// case those checks fail as that gives us the strongest policy.
+bool SandboxBroker::sRunningFromNetworkDrive = false;
+
+// Cached special directories used for adding policy rules.
+static StaticAutoPtr<nsString> sBinDir;
+static StaticAutoPtr<nsString> sProfileDir;
+static StaticAutoPtr<nsString> sLocalAppDataDir;
+#ifdef ENABLE_SYSTEM_EXTENSION_DIRS
+static StaticAutoPtr<nsString> sUserExtensionsDir;
+#endif
+
+static LazyLogModule sSandboxBrokerLog("SandboxBroker");
+
+#define LOG_E(...) MOZ_LOG(sSandboxBrokerLog, LogLevel::Error, (__VA_ARGS__))
+#define LOG_W(...) MOZ_LOG(sSandboxBrokerLog, LogLevel::Warning, (__VA_ARGS__))
+#define LOG_D(...) MOZ_LOG(sSandboxBrokerLog, LogLevel::Debug, (__VA_ARGS__))
+
+// Used to store whether we have accumulated an error combination for this
+// session.
+static StaticAutoPtr<nsTHashtable<nsCStringHashKey>> sLaunchErrors;
+
+// This helper function is our version of SandboxWin::AddWin32kLockdownPolicy
+// of Chromium, making sure the MITIGATION_WIN32K_DISABLE flag is set before
+// adding the SUBSYS_WIN32K_LOCKDOWN rule which is required by
+// PolicyBase::AddRuleInternal.
+static sandbox::ResultCode AddWin32kLockdownPolicy(
+    sandbox::TargetPolicy* aPolicy, bool aEnableOpm) {
+  sandbox::MitigationFlags flags = aPolicy->GetProcessMitigations();
+  MOZ_ASSERT(flags,
+             "Mitigations should be set before AddWin32kLockdownPolicy.");
+  MOZ_ASSERT(!(flags & sandbox::MITIGATION_WIN32K_DISABLE),
+             "Check not enabling twice.  Should not happen.");
+
+  flags |= sandbox::MITIGATION_WIN32K_DISABLE;
+  sandbox::ResultCode result = aPolicy->SetProcessMitigations(flags);
+  if (result != sandbox::SBOX_ALL_OK) {
+    return result;
+  }
+
+  result =
+      aPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_WIN32K_LOCKDOWN,
+                       aEnableOpm ? sandbox::TargetPolicy::IMPLEMENT_OPM_APIS
+                                  : sandbox::TargetPolicy::FAKE_USER_GDI_INIT,
+                       nullptr);
+  if (result != sandbox::SBOX_ALL_OK) {
+    return result;
+  }
+  if (aEnableOpm) {
+    aPolicy->SetEnableOPMRedirection();
+  }
+
+  return result;
+}
+
+/* static */
+void SandboxBroker::Initialize(sandbox::BrokerServices* aBrokerServices) {
+  sBrokerService = aBrokerServices;
+
+  sRunningFromNetworkDrive = widget::WinUtils::RunningFromANetworkDrive();
+}
+
+static void CacheDirAndAutoClear(nsIProperties* aDirSvc, const char* aDirKey,
+                                 StaticAutoPtr<nsString>* cacheVar) {
+  nsCOMPtr<nsIFile> dirToCache;
+  nsresult rv =
+      aDirSvc->Get(aDirKey, NS_GET_IID(nsIFile), getter_AddRefs(dirToCache));
+  if (NS_FAILED(rv)) {
+    // This can only be an NS_WARNING, because it can fail for xpcshell tests.
+    NS_WARNING("Failed to get directory to cache.");
+    LOG_E("Failed to get directory to cache, key: %s.", aDirKey);
+    return;
+  }
+
+  *cacheVar = new nsString();
+  ClearOnShutdown(cacheVar);
+  MOZ_ALWAYS_SUCCEEDS(dirToCache->GetPath(**cacheVar));
+
+  // Convert network share path to format for sandbox policy.
+  if (Substring(**cacheVar, 0, 2).Equals(u"\\\\"_ns)) {
+    (*cacheVar)->InsertLiteral(u"??\\UNC", 1);
+  }
+}
+
+/* static */
+void SandboxBroker::GeckoDependentInitialize() {
+  MOZ_ASSERT(NS_IsMainThread());
+
+  bool haveXPCOM = XRE_GetProcessType() != GeckoProcessType_RemoteSandboxBroker;
+  if (haveXPCOM) {
+    // Cache directory paths for use in policy rules, because the directory
+    // service must be called on the main thread.
+    nsresult rv;
+    nsCOMPtr<nsIProperties> dirSvc =
+        do_GetService(NS_DIRECTORY_SERVICE_CONTRACTID, &rv);
+    if (NS_FAILED(rv)) {
+      MOZ_ASSERT(false,
+                 "Failed to get directory service, cannot cache directories "
+                 "for rules.");
+      LOG_E(
+          "Failed to get directory service, cannot cache directories for "
+          "rules.");
+      return;
+    }
+
+    CacheDirAndAutoClear(dirSvc, NS_GRE_DIR, &sBinDir);
+    CacheDirAndAutoClear(dirSvc, NS_APP_USER_PROFILE_50_DIR, &sProfileDir);
+    CacheDirAndAutoClear(dirSvc, NS_WIN_LOCAL_APPDATA_DIR, &sLocalAppDataDir);
+#ifdef ENABLE_SYSTEM_EXTENSION_DIRS
+    CacheDirAndAutoClear(dirSvc, XRE_USER_SYS_EXTENSION_DIR,
+                         &sUserExtensionsDir);
+#endif
+  }
+
+  // Create sLaunchErrors up front because ClearOnShutdown must be called on the
+  // main thread.
+  sLaunchErrors = new nsTHashtable<nsCStringHashKey>();
+  ClearOnShutdown(&sLaunchErrors);
+}
+
+SandboxBroker::SandboxBroker() {
+  if (sBrokerService) {
+    scoped_refptr<sandbox::TargetPolicy> policy =
+        sBrokerService->CreatePolicy();
+    mPolicy = policy.get();
+    mPolicy->AddRef();
+    if (sRunningFromNetworkDrive) {
+      mPolicy->SetDoNotUseRestrictingSIDs();
+    }
+  } else {
+    mPolicy = nullptr;
+  }
+}
+
+#define WSTRING(STRING) L"" STRING
+
+static void AddMozLogRulesToPolicy(sandbox::TargetPolicy* aPolicy,
+                                   const base::EnvironmentMap& aEnvironment) {
+  auto it = aEnvironment.find(ENVIRONMENT_LITERAL("MOZ_LOG_FILE"));
+  if (it == aEnvironment.end()) {
+    it = aEnvironment.find(ENVIRONMENT_LITERAL("NSPR_LOG_FILE"));
+  }
+  if (it == aEnvironment.end()) {
+    return;
+  }
+
+  char const* logFileModules = getenv("MOZ_LOG");
+  if (!logFileModules) {
+    return;
+  }
+
+  // MOZ_LOG files have a standard file extension appended.
+  std::wstring logFileName(it->second);
+  logFileName.append(WSTRING(MOZ_LOG_FILE_EXTENSION));
+
+  // Allow for rotation number if rotate is on in the MOZ_LOG settings.
+  bool rotate = false;
+  NSPRLogModulesParser(
+      logFileModules,
+      [&rotate](const char* aName, LogLevel aLevel, int32_t aValue) {
+        if (strcmp(aName, "rotate") == 0) {
+          // Less or eq zero means to turn rotate off.
+          rotate = aValue > 0;
+        }
+      });
+  if (rotate) {
+    logFileName.append(L".?");
+  }
+
+  // Allow for %PID token in the filename. We don't allow it in the dir path, if
+  // specified, because we have to use a wildcard as we don't know the PID yet.
+  auto pidPos = logFileName.find(WSTRING(MOZ_LOG_PID_TOKEN));
+  auto lastSlash = logFileName.find_last_of(L"/\\");
+  if (pidPos != std::wstring::npos &&
+      (lastSlash == std::wstring::npos || lastSlash < pidPos)) {
+    logFileName.replace(pidPos, strlen(MOZ_LOG_PID_TOKEN), L"*");
+  }
+
+  aPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                   sandbox::TargetPolicy::FILES_ALLOW_ANY, logFileName.c_str());
+}
+
+static void AddDeveloperRepoDirToPolicy(sandbox::TargetPolicy* aPolicy) {
+  const wchar_t* developer_repo_dir =
+      _wgetenv(WSTRING("MOZ_DEVELOPER_REPO_DIR"));
+  if (!developer_repo_dir) {
+    return;
+  }
+
+  std::wstring repoPath(developer_repo_dir);
+  std::replace(repoPath.begin(), repoPath.end(), '/', '\\');
+  repoPath.append(WSTRING("\\*"));
+
+  aPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                   sandbox::TargetPolicy::FILES_ALLOW_READONLY,
+                   repoPath.c_str());
+}
+
+#undef WSTRING
+
+Result<Ok, mozilla::ipc::LaunchError> SandboxBroker::LaunchApp(
+    const wchar_t* aPath, const wchar_t* aArguments,
+    base::EnvironmentMap& aEnvironment, GeckoProcessType aProcessType,
+    const bool aEnableLogging, const IMAGE_THUNK_DATA* aCachedNtdllThunk,
+    void** aProcessHandle) {
+  if (!sBrokerService) {
+    return Err(mozilla::ipc::LaunchError("SB::LA::sBrokerService"));
+  }
+
+  if (!mPolicy) {
+    return Err(mozilla::ipc::LaunchError("SB::LA::mPolicy"));
+  }
+
+  // Set stdout and stderr, to allow inheritance for logging.
+  mPolicy->SetStdoutHandle(::GetStdHandle(STD_OUTPUT_HANDLE));
+  mPolicy->SetStderrHandle(::GetStdHandle(STD_ERROR_HANDLE));
+
+  // If we're running from a network drive then we can't block loading from
+  // remote locations. Strangely using MITIGATION_IMAGE_LOAD_NO_LOW_LABEL in
+  // this situation also means the process fails to start (bug 1423296).
+  if (sRunningFromNetworkDrive) {
+    sandbox::MitigationFlags mitigations = mPolicy->GetProcessMitigations();
+    mitigations &= ~(sandbox::MITIGATION_IMAGE_LOAD_NO_REMOTE |
+                     sandbox::MITIGATION_IMAGE_LOAD_NO_LOW_LABEL);
+    MOZ_RELEASE_ASSERT(
+        mPolicy->SetProcessMitigations(mitigations) == sandbox::SBOX_ALL_OK,
+        "Setting the reduced set of flags should always succeed");
+  }
+
+  // If logging enabled, set up the policy.
+  if (aEnableLogging) {
+    ApplyLoggingPolicy();
+  }
+
+#if defined(DEBUG)
+  // Allow write access to TEMP directory in debug builds for logging purposes.
+  // The path from GetTempPathW can have a length up to MAX_PATH + 1, including
+  // the null, so we need MAX_PATH + 2, so we can add an * to the end.
+  wchar_t tempPath[MAX_PATH + 2];
+  uint32_t pathLen = ::GetTempPathW(MAX_PATH + 1, tempPath);
+  if (pathLen > 0) {
+    // GetTempPath path ends with \ and returns the length without the null.
+    tempPath[pathLen] = L'*';
+    tempPath[pathLen + 1] = L'\0';
+    mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                     sandbox::TargetPolicy::FILES_ALLOW_ANY, tempPath);
+  }
+#endif
+
+  // Enable the child process to write log files when setup
+  AddMozLogRulesToPolicy(mPolicy, aEnvironment);
+
+  if (!mozilla::IsPackagedBuild()) {
+    AddDeveloperRepoDirToPolicy(mPolicy);
+  }
+
+  // Create the sandboxed process
+  PROCESS_INFORMATION targetInfo = {0};
+  sandbox::ResultCode result;
+  sandbox::ResultCode last_warning = sandbox::SBOX_ALL_OK;
+  DWORD last_error = ERROR_SUCCESS;
+  result = sBrokerService->SpawnTarget(aPath, aArguments, aEnvironment, mPolicy,
+                                       &last_warning, &last_error, &targetInfo);
+  if (sandbox::SBOX_ALL_OK != result) {
+    nsAutoCString key;
+    key.AppendASCII(XRE_GeckoProcessTypeToString(aProcessType));
+    key.AppendLiteral("/0x");
+    key.AppendInt(static_cast<uint32_t>(last_error), 16);
+
+    // Only accumulate for each combination once per session.
+    if (sLaunchErrors) {
+      if (!sLaunchErrors->Contains(key)) {
+        Telemetry::Accumulate(Telemetry::SANDBOX_FAILED_LAUNCH_KEYED, key,
+                              result);
+        sLaunchErrors->PutEntry(key);
+      }
+    } else {
+      // If sLaunchErrors not created yet then always accumulate.
+      Telemetry::Accumulate(Telemetry::SANDBOX_FAILED_LAUNCH_KEYED, key,
+                            result);
+    }
+
+    LOG_E(
+        "Failed (ResultCode %d) to SpawnTarget with last_error=%lu, "
+        "last_warning=%d",
+        result, last_error, last_warning);
+
+    return Err(mozilla::ipc::LaunchError("SB::LA::SpawnTarget", last_error));
+  } else if (sandbox::SBOX_ALL_OK != last_warning) {
+    // If there was a warning (but the result was still ok), log it and proceed.
+    LOG_W("Warning on SpawnTarget with last_error=%lu, last_warning=%d",
+          last_error, last_warning);
+  }
+
+#ifdef MOZ_THUNDERBIRD
+  // In Thunderbird, mInitDllBlocklistOOP is null, so InitDllBlocklistOOP would
+  // hit MOZ_RELEASE_ASSERT.
+  constexpr bool isThunderbird = true;
+#else
+  constexpr bool isThunderbird = false;
+#endif
+
+  if (!isThunderbird &&
+      XRE_GetChildProcBinPathType(aProcessType) == BinPathType::Self) {
+    RefPtr<DllServices> dllSvc(DllServices::Get());
+    LauncherVoidResultWithLineInfo blocklistInitOk =
+        dllSvc->InitDllBlocklistOOP(aPath, targetInfo.hProcess,
+                                    aCachedNtdllThunk, aProcessType);
+    if (blocklistInitOk.isErr()) {
+      dllSvc->HandleLauncherError(blocklistInitOk.unwrapErr(),
+                                  XRE_GeckoProcessTypeToString(aProcessType));
+      LOG_E("InitDllBlocklistOOP failed at %s:%d with HRESULT 0x%08lX",
+            blocklistInitOk.unwrapErr().mFile,
+            blocklistInitOk.unwrapErr().mLine,
+            blocklistInitOk.unwrapErr().mError.AsHResult());
+      TerminateProcess(targetInfo.hProcess, 1);
+      CloseHandle(targetInfo.hThread);
+      CloseHandle(targetInfo.hProcess);
+      return Err(mozilla::ipc::LaunchError(
+          "InitDllBlocklistOOP",
+          blocklistInitOk.unwrapErr().mError.AsHResult()));
+    }
+  } else {
+    // Load the child executable as a datafile so that we can examine its
+    // headers without doing a full load with dependencies and such.
+    nsModuleHandle moduleHandle(
+        ::LoadLibraryExW(aPath, nullptr, LOAD_LIBRARY_AS_DATAFILE));
+    if (moduleHandle) {
+      nt::CrossExecTransferManager transferMgr(targetInfo.hProcess,
+                                               moduleHandle);
+      if (!!transferMgr) {
+        LauncherVoidResult importsRestored =
+            RestoreImportDirectory(aPath, transferMgr);
+        if (importsRestored.isErr()) {
+          RefPtr<DllServices> dllSvc(DllServices::Get());
+          dllSvc->HandleLauncherError(
+              importsRestored.unwrapErr(),
+              XRE_GeckoProcessTypeToString(aProcessType));
+          LOG_E("Failed to restore import directory with HRESULT 0x%08lX",
+                importsRestored.unwrapErr().mError.AsHResult());
+          TerminateProcess(targetInfo.hProcess, 1);
+          CloseHandle(targetInfo.hThread);
+          CloseHandle(targetInfo.hProcess);
+          return Err(mozilla::ipc::LaunchError(
+              "RestoreImportDirectory",
+              importsRestored.unwrapErr().mError.AsHResult()));
+        }
+      }
+    }
+  }
+
+  // The sandboxed process is started in a suspended state, resume it now that
+  // we've set things up.
+  ResumeThread(targetInfo.hThread);
+  CloseHandle(targetInfo.hThread);
+
+  // Return the process handle to the caller
+  *aProcessHandle = targetInfo.hProcess;
+
+  return Ok();
+}
+
+static void AddCachedDirRule(sandbox::TargetPolicy* aPolicy,
+                             sandbox::TargetPolicy::Semantics aAccess,
+                             const StaticAutoPtr<nsString>& aBaseDir,
+                             const nsLiteralString& aRelativePath) {
+  if (!aBaseDir) {
+    // This can only be an NS_WARNING, because it can null for xpcshell tests.
+    NS_WARNING("Tried to add rule with null base dir.");
+    LOG_E("Tried to add rule with null base dir. Relative path: %S, Access: %d",
+          static_cast<const wchar_t*>(aRelativePath.get()), aAccess);
+    return;
+  }
+
+  nsAutoString rulePath(*aBaseDir);
+  rulePath.Append(aRelativePath);
+
+  sandbox::ResultCode result = aPolicy->AddRule(
+      sandbox::TargetPolicy::SUBSYS_FILES, aAccess, rulePath.get());
+  if (sandbox::SBOX_ALL_OK != result) {
+    NS_ERROR("Failed to add file policy rule.");
+    LOG_E("Failed (ResultCode %d) to add %d access to: %S", result, aAccess,
+          static_cast<const wchar_t*>(rulePath.get()));
+  }
+}
+
+// This function caches and returns an array of NT paths of the executable's
+// dependent modules.
+// If this returns Nothing(), it means the retrieval of the modules failed
+// (e.g. when the launcher process is disabled), so the process should not
+// enable pre-spawn CIG.
+static const Maybe<Vector<const wchar_t*>>& GetPrespawnCigExceptionModules() {
+  // We enable pre-spawn CIG only in Nightly for now
+  // because it caused a compat issue (bug 1682304 and 1704373).
+#if defined(NIGHTLY_BUILD)
+  // The shared section contains a list of dependent modules as a
+  // null-delimited string.  We convert it to a string vector and
+  // cache it to avoid converting the same data every time.
+  static Maybe<Vector<const wchar_t*>> sDependentModules =
+      []() -> Maybe<Vector<const wchar_t*>> {
+    RefPtr<DllServices> dllSvc(DllServices::Get());
+    auto sharedSection = dllSvc->GetSharedSection();
+    if (!sharedSection) {
+      return Nothing();
+    }
+
+    return sharedSection->GetDependentModules();
+  }();
+
+  return sDependentModules;
+#else
+  static const Maybe<Vector<const wchar_t*>> sNothing = Nothing();
+  return sNothing;
+#endif
+}
+
+static sandbox::ResultCode AllowProxyLoadFromBinDir(
+    sandbox::TargetPolicy* aPolicy) {
+  // Allow modules in the directory containing the executable such as
+  // mozglue.dll, nss3.dll, etc.
+  static UniquePtr<nsString> sInstallDir;
+  if (!sInstallDir) {
+    // Since this function can be called before sBinDir is initialized,
+    // we cache the install path by ourselves.
+    UniquePtr<wchar_t[]> appDirStr;
+    if (GetInstallDirectory(appDirStr)) {
+      sInstallDir = MakeUnique<nsString>(appDirStr.get());
+      sInstallDir->Append(u"\\*");
+
+      auto setClearOnShutdown = [ptr = &sInstallDir]() -> void {
+        ClearOnShutdown(ptr);
+      };
+      if (NS_IsMainThread()) {
+        setClearOnShutdown();
+      } else {
+        SchedulerGroup::Dispatch(NS_NewRunnableFunction(
+            "InitSignedPolicyRulesToBypassCig", std::move(setClearOnShutdown)));
+      }
+    }
+
+    if (!sInstallDir) {
+      return sandbox::SBOX_ERROR_GENERIC;
+    }
+  }
+  return aPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_SIGNED_BINARY,
+                          sandbox::TargetPolicy::SIGNED_ALLOW_LOAD,
+                          sInstallDir->get());
+}
+
+static sandbox::ResultCode AddCigToPolicy(
+    sandbox::TargetPolicy* aPolicy, bool aAlwaysProxyBinDirLoading = false) {
+  const Maybe<Vector<const wchar_t*>>& exceptionModules =
+      GetPrespawnCigExceptionModules();
+  if (exceptionModules.isNothing()) {
+    sandbox::MitigationFlags delayedMitigations =
+        aPolicy->GetDelayedProcessMitigations();
+    MOZ_ASSERT(delayedMitigations,
+               "Delayed mitigations should be set before AddCigToPolicy.");
+    MOZ_ASSERT(!(delayedMitigations & sandbox::MITIGATION_FORCE_MS_SIGNED_BINS),
+               "AddCigToPolicy should not be called twice.");
+
+    delayedMitigations |= sandbox::MITIGATION_FORCE_MS_SIGNED_BINS;
+    sandbox::ResultCode result =
+        aPolicy->SetDelayedProcessMitigations(delayedMitigations);
+    if (result != sandbox::SBOX_ALL_OK) {
+      return result;
+    }
+
+    if (aAlwaysProxyBinDirLoading) {
+      result = AllowProxyLoadFromBinDir(aPolicy);
+    }
+    return result;
+  }
+
+  sandbox::MitigationFlags mitigations = aPolicy->GetProcessMitigations();
+  MOZ_ASSERT(mitigations, "Mitigations should be set before AddCigToPolicy.");
+  MOZ_ASSERT(!(mitigations & sandbox::MITIGATION_FORCE_MS_SIGNED_BINS),
+             "AddCigToPolicy should not be called twice.");
+
+  mitigations |= sandbox::MITIGATION_FORCE_MS_SIGNED_BINS;
+  sandbox::ResultCode result = aPolicy->SetProcessMitigations(mitigations);
+  if (result != sandbox::SBOX_ALL_OK) {
+    return result;
+  }
+
+  result = AllowProxyLoadFromBinDir(aPolicy);
+  if (result != sandbox::SBOX_ALL_OK) {
+    return result;
+  }
+
+  for (const wchar_t* path : exceptionModules.ref()) {
+    result = aPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_SIGNED_BINARY,
+                              sandbox::TargetPolicy::SIGNED_ALLOW_LOAD, path);
+    if (result != sandbox::SBOX_ALL_OK) {
+      return result;
+    }
+  }
+
+  return sandbox::SBOX_ALL_OK;
+}
+
+// Returns the most strict dynamic code mitigation flag that is compatible with
+// system libraries MSAudDecMFT.dll and msmpeg2vdec.dll. This depends on the
+// Windows version and the architecture. See bug 1783223 comment 27.
+//
+// Use the result with SetDelayedProcessMitigations. Using non-delayed ACG
+// results in incompatibility with third-party antivirus software, the Windows
+// internal Shim Engine mechanism, parts of our own DLL blocklist code, and
+// AddressSanitizer initialization code. See bug 1783223.
+static sandbox::MitigationFlags DynamicCodeFlagForSystemMediaLibraries() {
+  static auto dynamicCodeFlag = []() {
+#ifdef _M_X64
+    if (IsWin10CreatorsUpdateOrLater()) {
+      return sandbox::MITIGATION_DYNAMIC_CODE_DISABLE;
+    }
+#endif  // _M_X64
+
+    if (IsWin10AnniversaryUpdateOrLater()) {
+      return sandbox::MITIGATION_DYNAMIC_CODE_DISABLE_WITH_OPT_OUT;
+    }
+
+    return sandbox::MitigationFlags{};
+  }();
+  return dynamicCodeFlag;
+}
+
+// Process fails to start in LPAC with ASan build
+#if !defined(MOZ_ASAN)
+static void HexEncode(const Span<const uint8_t>& aBytes, nsACString& aEncoded) {
+  static const char kHexChars[] = "0123456789abcdef";
+
+  // Each input byte creates two output hex characters.
+  char* encodedPtr;
+  aEncoded.GetMutableData(&encodedPtr, aBytes.size() * 2);
+
+  for (auto byte : aBytes) {
+    *(encodedPtr++) = kHexChars[byte >> 4];
+    *(encodedPtr++) = kHexChars[byte & 0xf];
+  }
+}
+
+// This is left as a void because we might fail to set the permission for some
+// reason and yet the LPAC permission is already granted. So returning success
+// or failure isn't really that useful.
+/* static */
+void SandboxBroker::EnsureLpacPermsissionsOnDir(const nsString& aDir) {
+  // For MSIX packages we get access through the packageContents capability and
+  // we probably won't have access to add the permission either way.
+  if (widget::WinUtils::HasPackageIdentity()) {
+    return;
+  }
+
+  BYTE sidBytes[SECURITY_MAX_SID_SIZE];
+  PSID lpacFirefoxInstallFilesSid = static_cast<PSID>(sidBytes);
+  if (!sBrokerService->DeriveCapabilitySidFromName(kLpacFirefoxInstallFiles,
+                                                   lpacFirefoxInstallFilesSid,
+                                                   sizeof(sidBytes))) {
+    LOG_E("Failed to derive Firefox install files capability SID.");
+    return;
+  }
+
+  HANDLE hDir = ::CreateFileW(aDir.get(), WRITE_DAC | READ_CONTROL, 0, NULL,
+                              OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, NULL);
+  if (hDir == INVALID_HANDLE_VALUE) {
+    LOG_W("Unable to get directory handle for %s",
+          NS_ConvertUTF16toUTF8(aDir).get());
+    return;
+  }
+
+  UniquePtr<HANDLE, CloseHandleDeleter> autoHandleCloser(hDir);
+  PACL pBinDirAcl = nullptr;
+  PSECURITY_DESCRIPTOR pSD = nullptr;
+  DWORD result =
+      ::GetSecurityInfo(hDir, SE_FILE_OBJECT, DACL_SECURITY_INFORMATION,
+                        nullptr, nullptr, &pBinDirAcl, nullptr, &pSD);
+  if (result != ERROR_SUCCESS) {
+    LOG_E("Failed to get DACL for %s", NS_ConvertUTF16toUTF8(aDir).get());
+    return;
+  }
+
+  UniquePtr<VOID, LocalFreeDeleter> autoFreeSecDesc(pSD);
+  if (!pBinDirAcl) {
+    LOG_E("DACL was null for %s", NS_ConvertUTF16toUTF8(aDir).get());
+    return;
+  }
+
+  for (DWORD i = 0; i < pBinDirAcl->AceCount; ++i) {
+    VOID* pAce = nullptr;
+    if (!::GetAce(pBinDirAcl, i, &pAce) ||
+        static_cast<PACE_HEADER>(pAce)->AceType != ACCESS_ALLOWED_ACE_TYPE) {
+      continue;
+    }
+
+    auto* pAllowedAce = static_cast<ACCESS_ALLOWED_ACE*>(pAce);
+    if ((pAllowedAce->Mask & (GENERIC_READ | GENERIC_EXECUTE)) !=
+        (GENERIC_READ | GENERIC_EXECUTE)) {
+      continue;
+    }
+
+    PSID aceSID = reinterpret_cast<PSID>(&(pAllowedAce->SidStart));
+    if (::EqualSid(aceSID, lpacFirefoxInstallFilesSid)) {
+      LOG_D("Firefox install files permission found on %s",
+            NS_ConvertUTF16toUTF8(aDir).get());
+      return;
+    }
+  }
+
+  EXPLICIT_ACCESS_W newAccess = {0};
+  newAccess.grfAccessMode = GRANT_ACCESS;
+  newAccess.grfAccessPermissions = GENERIC_READ | GENERIC_EXECUTE;
+  newAccess.grfInheritance = SUB_CONTAINERS_AND_OBJECTS_INHERIT;
+  ::BuildTrusteeWithSidW(&newAccess.Trustee, lpacFirefoxInstallFilesSid);
+  PACL newDacl = nullptr;
+  if (ERROR_SUCCESS !=
+      ::SetEntriesInAclW(1, &newAccess, pBinDirAcl, &newDacl)) {
+    LOG_E("Failed to create new DACL with Firefox install files SID.");
+    return;
+  }
+
+  UniquePtr<ACL, LocalFreeDeleter> autoFreeAcl(newDacl);
+  if (ERROR_SUCCESS != ::SetSecurityInfo(hDir, SE_FILE_OBJECT,
+                                         DACL_SECURITY_INFORMATION, nullptr,
+                                         nullptr, newDacl, nullptr)) {
+    LOG_E("Failed to set new DACL on %s", NS_ConvertUTF16toUTF8(aDir).get());
+  }
+
+  LOG_D("Firefox install files permission granted on %s",
+        NS_ConvertUTF16toUTF8(aDir).get());
+}
+
+static bool IsLowPrivilegedAppContainerSupported() {
+  // Chromium doesn't support adding an LPAC before this version due to
+  // incompatibility with some process mitigations.
+  return IsWin10Sep2018UpdateOrLater();
+}
+
+// AddAndConfigureAppContainerProfile deliberately fails if it is called on an
+// unsupported version. This is because for some process types the LPAC is
+// required to provide a sufficiently strong sandbox. Processes where the use of
+// an LPAC is an optional extra should use IsLowPrivilegedAppContainerSupported
+// to check support first.
+static sandbox::ResultCode AddAndConfigureAppContainerProfile(
+    sandbox::TargetPolicy* aPolicy, const nsAString& aPackagePrefix,
+    const nsTArray<sandbox::WellKnownCapabilities>& aWellKnownCapabilites,
+    const nsTArray<const wchar_t*>& aNamedCapabilites) {
+  // CreateAppContainerProfile requires that the profile name is at most 64
+  // characters but 50 on WCOS systems. The size of sha1 is a constant 40,
+  // so validate that the base names are sufficiently short that the total
+  // length is valid on all systems.
+  MOZ_ASSERT(aPackagePrefix.Length() <= 10U,
+             "AppContainer Package prefix too long.");
+
+  if (!IsLowPrivilegedAppContainerSupported()) {
+    return sandbox::SBOX_ERROR_UNSUPPORTED;
+  }
+
+  static nsAutoString uniquePackageStr = []() {
+    // userenv.dll may not have been loaded and some of the chromium sandbox
+    // AppContainer code assumes that it is. Done here to load once.
+    ::LoadLibraryW(L"userenv.dll");
+
+    // Done during the package string initialization so we only do it once.
+    SandboxBroker::EnsureLpacPermsissionsOnDir(*sBinDir.get());
+
+    // This mirrors Edge's use of the exe path for the SHA1 hash to give a
+    // machine unique name per install.
+    nsAutoString ret;
+    char exePathBuf[MAX_PATH];
+    DWORD pathSize = ::GetModuleFileNameA(nullptr, exePathBuf, MAX_PATH);
+    if (!pathSize) {
+      return ret;
+    }
+
+    SHA1Sum sha1Sum;
+    SHA1Sum::Hash sha1Hash;
+    sha1Sum.update(exePathBuf, pathSize);
+    sha1Sum.finish(sha1Hash);
+
+    nsAutoCString hexEncoded;
+    HexEncode(sha1Hash, hexEncoded);
+    ret = NS_ConvertUTF8toUTF16(hexEncoded);
+    return ret;
+  }();
+
+  if (uniquePackageStr.IsEmpty()) {
+    return sandbox::SBOX_ERROR_CREATE_APPCONTAINER_PROFILE;
+  }
+
+  // The bool parameter is called create_profile, but in fact it tries to create
+  // and then opens if it already exists. So always passing true is fine.
+  bool createOrOpenProfile = true;
+  nsAutoString packageName = aPackagePrefix + uniquePackageStr;
+  sandbox::ResultCode result =
+      aPolicy->AddAppContainerProfile(packageName.get(), createOrOpenProfile);
+  if (result != sandbox::SBOX_ALL_OK) {
+    return result;
+  }
+
+  // This looks odd, but unfortunately holding a scoped_refptr and
+  // dereferencing has DCHECKs that cause a linking problem.
+  sandbox::AppContainerProfile* profile =
+      aPolicy->GetAppContainerProfile().get();
+  profile->SetEnableLowPrivilegeAppContainer(true);
+
+  for (auto wkCap : aWellKnownCapabilites) {
+    if (!profile->AddCapability(wkCap)) {
+      return sandbox::SBOX_ERROR_CREATE_APPCONTAINER_PROFILE_CAPABILITY;
+    }
+  }
+
+  for (auto namedCap : aNamedCapabilites) {
+    if (!profile->AddCapability(namedCap)) {
+      return sandbox::SBOX_ERROR_CREATE_APPCONTAINER_PROFILE_CAPABILITY;
+    }
+  }
+
+  return sandbox::SBOX_ALL_OK;
+}
+#endif
+
+void SandboxBroker::SetSecurityLevelForContentProcess(int32_t aSandboxLevel,
+                                                      bool aIsFileProcess) {
+  MOZ_RELEASE_ASSERT(mPolicy, "mPolicy must be set before this call.");
+
+  sandbox::JobLevel jobLevel;
+  sandbox::TokenLevel accessTokenLevel;
+  sandbox::IntegrityLevel initialIntegrityLevel;
+  sandbox::IntegrityLevel delayedIntegrityLevel;
+
+  // The setting of these levels is pretty arbitrary, but they are a useful (if
+  // crude) tool while we are tightening the policy. Gaps are left to try and
+  // avoid changing their meaning.
+  MOZ_RELEASE_ASSERT(aSandboxLevel >= 1,
+                     "Should not be called with aSandboxLevel < 1");
+  if (aSandboxLevel >= 20) {
+    jobLevel = sandbox::JOB_LOCKDOWN;
+    accessTokenLevel = sandbox::USER_LOCKDOWN;
+    initialIntegrityLevel = sandbox::INTEGRITY_LEVEL_LOW;
+    delayedIntegrityLevel = sandbox::INTEGRITY_LEVEL_UNTRUSTED;
+  } else if (aSandboxLevel >= 7) {
+    jobLevel = sandbox::JOB_LOCKDOWN;
+    accessTokenLevel = sandbox::USER_LIMITED;
+    initialIntegrityLevel = sandbox::INTEGRITY_LEVEL_LOW;
+    delayedIntegrityLevel = sandbox::INTEGRITY_LEVEL_UNTRUSTED;
+  } else if (aSandboxLevel >= 4) {
+    jobLevel = sandbox::JOB_LOCKDOWN;
+    accessTokenLevel = sandbox::USER_LIMITED;
+    initialIntegrityLevel = sandbox::INTEGRITY_LEVEL_LOW;
+    delayedIntegrityLevel = sandbox::INTEGRITY_LEVEL_LOW;
+  } else if (aSandboxLevel >= 3) {
+    jobLevel = sandbox::JOB_RESTRICTED;
+    accessTokenLevel = sandbox::USER_LIMITED;
+    initialIntegrityLevel = sandbox::INTEGRITY_LEVEL_LOW;
+    delayedIntegrityLevel = sandbox::INTEGRITY_LEVEL_LOW;
+  } else if (aSandboxLevel == 2) {
+    jobLevel = sandbox::JOB_INTERACTIVE;
+    accessTokenLevel = sandbox::USER_INTERACTIVE;
+    initialIntegrityLevel = sandbox::INTEGRITY_LEVEL_LOW;
+    delayedIntegrityLevel = sandbox::INTEGRITY_LEVEL_LOW;
+  } else {
+    MOZ_ASSERT(aSandboxLevel == 1);
+
+    jobLevel = sandbox::JOB_NONE;
+    accessTokenLevel = sandbox::USER_NON_ADMIN;
+    initialIntegrityLevel = sandbox::INTEGRITY_LEVEL_LOW;
+    delayedIntegrityLevel = sandbox::INTEGRITY_LEVEL_LOW;
+  }
+
+  // If the process will handle file: URLs, don't allow settings that
+  // block reads.
+  if (aIsFileProcess) {
+    if (accessTokenLevel < sandbox::USER_NON_ADMIN) {
+      accessTokenLevel = sandbox::USER_NON_ADMIN;
+    }
+    if (delayedIntegrityLevel > sandbox::INTEGRITY_LEVEL_LOW) {
+      delayedIntegrityLevel = sandbox::INTEGRITY_LEVEL_LOW;
+    }
+  }
+
+#if defined(DEBUG)
+  // This is required for a MOZ_ASSERT check in WindowsMessageLoop.cpp
+  // WinEventHook, see bug 1366694 for details.
+  DWORD uiExceptions = JOB_OBJECT_UILIMIT_HANDLES;
+#else
+  DWORD uiExceptions = 0;
+#endif
+  sandbox::ResultCode result = mPolicy->SetJobLevel(jobLevel, uiExceptions);
+  MOZ_RELEASE_ASSERT(sandbox::SBOX_ALL_OK == result,
+                     "Setting job level failed, have you set memory limit when "
+                     "jobLevel == JOB_NONE?");
+
+  // If the delayed access token is not restricted we don't want the initial one
+  // to be either, because it can interfere with running from a network drive.
+  sandbox::TokenLevel initialAccessTokenLevel =
+      (accessTokenLevel == sandbox::USER_UNPROTECTED ||
+       accessTokenLevel == sandbox::USER_NON_ADMIN)
+          ? sandbox::USER_UNPROTECTED
+          : sandbox::USER_RESTRICTED_SAME_ACCESS;
+
+  result = mPolicy->SetTokenLevel(initialAccessTokenLevel, accessTokenLevel);
+  MOZ_RELEASE_ASSERT(sandbox::SBOX_ALL_OK == result,
+                     "Lockdown level cannot be USER_UNPROTECTED or USER_LAST "
+                     "if initial level was USER_RESTRICTED_SAME_ACCESS");
+
+  result = mPolicy->SetIntegrityLevel(initialIntegrityLevel);
+  MOZ_RELEASE_ASSERT(sandbox::SBOX_ALL_OK == result,
+                     "SetIntegrityLevel should never fail, what happened?");
+  result = mPolicy->SetDelayedIntegrityLevel(delayedIntegrityLevel);
+  MOZ_RELEASE_ASSERT(
+      sandbox::SBOX_ALL_OK == result,
+      "SetDelayedIntegrityLevel should never fail, what happened?");
+
+  if (aSandboxLevel > 5) {
+    mPolicy->SetLockdownDefaultDacl();
+    mPolicy->AddRestrictingRandomSid();
+  }
+
+  if (aSandboxLevel > 4) {
+    // Alternate winstation breaks native theming.
+    bool useAlternateWinstation =
+        StaticPrefs::widget_non_native_theme_enabled();
+    result = mPolicy->SetAlternateDesktop(useAlternateWinstation);
+    if (NS_WARN_IF(result != sandbox::SBOX_ALL_OK)) {
+      LOG_W("SetAlternateDesktop failed, result: %i, last error: %lx", result,
+            ::GetLastError());
+    }
+  }
+
+  sandbox::MitigationFlags mitigations =
+      sandbox::MITIGATION_BOTTOM_UP_ASLR | sandbox::MITIGATION_HEAP_TERMINATE |
+      sandbox::MITIGATION_SEHOP | sandbox::MITIGATION_DEP_NO_ATL_THUNK |
+      sandbox::MITIGATION_DEP | sandbox::MITIGATION_EXTENSION_POINT_DISABLE |
+      sandbox::MITIGATION_IMAGE_LOAD_NO_REMOTE |
+      sandbox::MITIGATION_IMAGE_LOAD_NO_LOW_LABEL |
+      sandbox::MITIGATION_IMAGE_LOAD_PREFER_SYS32;
+
+#if defined(_M_ARM64)
+  // Disable CFG on older versions of ARM64 Windows to avoid a crash in COM.
+  if (!IsWin10Sep2018UpdateOrLater()) {
+    mitigations |= sandbox::MITIGATION_CONTROL_FLOW_GUARD_DISABLE;
+  }
+#endif
+
+  if (StaticPrefs::security_sandbox_content_shadow_stack_enabled()) {
+    mitigations |= sandbox::MITIGATION_CET_COMPAT_MODE;
+  }
+
+  result = mPolicy->SetProcessMitigations(mitigations);
+  MOZ_RELEASE_ASSERT(sandbox::SBOX_ALL_OK == result,
+                     "Invalid flags for SetProcessMitigations.");
+
+  nsIXULRuntime::ContentWin32kLockdownState win32kLockdownState =
+      GetContentWin32kLockdownState();
+
+  LOG_W("Win32k Lockdown State: '%s'",
+        ContentWin32kLockdownStateToString(win32kLockdownState));
+
+  if (GetContentWin32kLockdownEnabled()) {
+    result = AddWin32kLockdownPolicy(mPolicy, false);
+    MOZ_RELEASE_ASSERT(result == sandbox::SBOX_ALL_OK,
+                       "Failed to add the win32k lockdown policy");
+  }
+
+  mitigations = sandbox::MITIGATION_STRICT_HANDLE_CHECKS |
+                sandbox::MITIGATION_DLL_SEARCH_ORDER;
+
+  result = mPolicy->SetDelayedProcessMitigations(mitigations);
+  MOZ_RELEASE_ASSERT(sandbox::SBOX_ALL_OK == result,
+                     "Invalid flags for SetDelayedProcessMitigations.");
+
+  // We still have edge cases where the child at low integrity can't read some
+  // files, so add a rule to allow read access to everything when required.
+  if (aSandboxLevel == 1 || aIsFileProcess) {
+    result =
+        mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                         sandbox::TargetPolicy::FILES_ALLOW_READONLY, L"*");
+    MOZ_RELEASE_ASSERT(sandbox::SBOX_ALL_OK == result,
+                       "With these static arguments AddRule should never fail, "
+                       "what happened?");
+  } else {
+    // Add rule to allow access to user specific fonts.
+    AddCachedDirRule(mPolicy, sandbox::TargetPolicy::FILES_ALLOW_READONLY,
+                     sLocalAppDataDir, u"\\Microsoft\\Windows\\Fonts\\*"_ns);
+
+    // Add rule to allow read access to installation directory.
+    AddCachedDirRule(mPolicy, sandbox::TargetPolicy::FILES_ALLOW_READONLY,
+                     sBinDir, u"\\*"_ns);
+
+    // Add rule to allow read access to the chrome directory within profile.
+    AddCachedDirRule(mPolicy, sandbox::TargetPolicy::FILES_ALLOW_READONLY,
+                     sProfileDir, u"\\chrome\\*"_ns);
+
+    // Add rule to allow read access to the extensions directory within profile.
+    AddCachedDirRule(mPolicy, sandbox::TargetPolicy::FILES_ALLOW_READONLY,
+                     sProfileDir, u"\\extensions\\*"_ns);
+
+#ifdef ENABLE_SYSTEM_EXTENSION_DIRS
+    // Add rule to allow read access to the per-user extensions directory.
+    AddCachedDirRule(mPolicy, sandbox::TargetPolicy::FILES_ALLOW_READONLY,
+                     sUserExtensionsDir, u"\\*"_ns);
+#endif
+  }
+
+  // Add the policy for the client side of a pipe. It is just a file
+  // in the \pipe\ namespace. We restrict it to pipes that start with
+  // "chrome." so the sandboxed process cannot connect to system services.
+  result = mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                            sandbox::TargetPolicy::FILES_ALLOW_ANY,
+                            L"\\??\\pipe\\chrome.*");
+  MOZ_RELEASE_ASSERT(
+      sandbox::SBOX_ALL_OK == result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  // Add the policy for the client side of the crash server pipe.
+  result = mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                            sandbox::TargetPolicy::FILES_ALLOW_ANY,
+                            L"\\??\\pipe\\gecko-crash-server-pipe.*");
+  MOZ_RELEASE_ASSERT(
+      sandbox::SBOX_ALL_OK == result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  // Allow content processes to use complex line breaking brokering.
+  result = mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_LINE_BREAK,
+                            sandbox::TargetPolicy::LINE_BREAK_ALLOW, nullptr);
+  MOZ_RELEASE_ASSERT(
+      sandbox::SBOX_ALL_OK == result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  if (aSandboxLevel >= 20) {
+    // Content process still needs to be able to read fonts.
+    wchar_t* fontsPath;
+    if (SUCCEEDED(
+            ::SHGetKnownFolderPath(FOLDERID_Fonts, 0, nullptr, &fontsPath))) {
+      std::wstring fontsStr = fontsPath;
+      ::CoTaskMemFree(fontsPath);
+      result = mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                                sandbox::TargetPolicy::FILES_ALLOW_READONLY,
+                                fontsStr.c_str());
+      if (sandbox::SBOX_ALL_OK != result) {
+        NS_ERROR("Failed to add fonts dir read access policy rule.");
+        LOG_E("Failed (ResultCode %d) to add read access to: %S", result,
+              fontsStr.c_str());
+      }
+
+      fontsStr += L"\\*";
+      result = mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                                sandbox::TargetPolicy::FILES_ALLOW_READONLY,
+                                fontsStr.c_str());
+      if (sandbox::SBOX_ALL_OK != result) {
+        NS_ERROR("Failed to add fonts read access policy rule.");
+        LOG_E("Failed (ResultCode %d) to add read access to: %S", result,
+              fontsStr.c_str());
+      }
+    }
+
+    // We still currently create IPC named pipes in the content process.
+    result = mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_NAMED_PIPES,
+                              sandbox::TargetPolicy::NAMEDPIPES_ALLOW_ANY,
+                              L"\\\\.\\pipe\\chrome.*");
+    MOZ_RELEASE_ASSERT(
+        sandbox::SBOX_ALL_OK == result,
+        "With these static arguments AddRule should never fail.");
+  }
+}
+
+void SandboxBroker::SetSecurityLevelForGPUProcess(int32_t aSandboxLevel) {
+  MOZ_RELEASE_ASSERT(mPolicy, "mPolicy must be set before this call.");
+  MOZ_RELEASE_ASSERT(aSandboxLevel >= 1);
+
+  sandbox::TokenLevel initialTokenLevel = sandbox::USER_RESTRICTED_SAME_ACCESS;
+  sandbox::TokenLevel lockdownTokenLevel =
+      (aSandboxLevel >= 2) ? sandbox::USER_LIMITED
+                           : sandbox::USER_RESTRICTED_NON_ADMIN;
+
+  sandbox::IntegrityLevel initialIntegrityLevel = sandbox::INTEGRITY_LEVEL_LOW;
+  sandbox::IntegrityLevel delayedIntegrityLevel = sandbox::INTEGRITY_LEVEL_LOW;
+
+  sandbox::JobLevel jobLevel = sandbox::JOB_LIMITED_USER;
+
+  uint32_t uiExceptions =
+      JOB_OBJECT_UILIMIT_SYSTEMPARAMETERS | JOB_OBJECT_UILIMIT_DESKTOP |
+      JOB_OBJECT_UILIMIT_EXITWINDOWS | JOB_OBJECT_UILIMIT_DISPLAYSETTINGS;
+
+  sandbox::MitigationFlags initialMitigations =
+      sandbox::MITIGATION_BOTTOM_UP_ASLR | sandbox::MITIGATION_HEAP_TERMINATE |
+      sandbox::MITIGATION_SEHOP | sandbox::MITIGATION_DEP_NO_ATL_THUNK |
+      sandbox::MITIGATION_IMAGE_LOAD_NO_REMOTE |
+      sandbox::MITIGATION_IMAGE_LOAD_NO_LOW_LABEL | sandbox::MITIGATION_DEP;
+
+  if (StaticPrefs::security_sandbox_gpu_shadow_stack_enabled()) {
+    initialMitigations |= sandbox::MITIGATION_CET_COMPAT_MODE;
+  }
+
+  sandbox::MitigationFlags delayedMitigations =
+      sandbox::MITIGATION_STRICT_HANDLE_CHECKS |
+      sandbox::MITIGATION_DLL_SEARCH_ORDER;
+
+  SANDBOX_SUCCEED_OR_CRASH(mPolicy->SetJobLevel(jobLevel, uiExceptions));
+  SANDBOX_SUCCEED_OR_CRASH(
+      mPolicy->SetTokenLevel(initialTokenLevel, lockdownTokenLevel));
+  SANDBOX_SUCCEED_OR_CRASH(mPolicy->SetIntegrityLevel(initialIntegrityLevel));
+  SANDBOX_SUCCEED_OR_CRASH(
+      mPolicy->SetDelayedIntegrityLevel(delayedIntegrityLevel));
+  SANDBOX_SUCCEED_OR_CRASH(mPolicy->SetProcessMitigations(initialMitigations));
+  SANDBOX_SUCCEED_OR_CRASH(
+      mPolicy->SetDelayedProcessMitigations(delayedMitigations));
+
+  mPolicy->SetLockdownDefaultDacl();
+  mPolicy->AddRestrictingRandomSid();
+
+  // Add the policy for the client side of a pipe. It is just a file
+  // in the \pipe\ namespace. We restrict it to pipes that start with
+  // "chrome." so the sandboxed process cannot connect to system services.
+  SANDBOX_SUCCEED_OR_CRASH(mPolicy->AddRule(
+      sandbox::TargetPolicy::SUBSYS_FILES,
+      sandbox::TargetPolicy::FILES_ALLOW_ANY, L"\\??\\pipe\\chrome.*"));
+
+  // Add the policy for the client side of the crash server pipe.
+  SANDBOX_SUCCEED_OR_CRASH(
+      mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                       sandbox::TargetPolicy::FILES_ALLOW_ANY,
+                       L"\\??\\pipe\\gecko-crash-server-pipe.*"));
+
+  // The GPU process needs to write to a shader cache for performance reasons
+  if (sProfileDir) {
+    AddCachedDirRule(mPolicy, sandbox::TargetPolicy::FILES_ALLOW_DIR_ANY,
+                     sProfileDir, u"\\shader-cache"_ns);
+
+    AddCachedDirRule(mPolicy, sandbox::TargetPolicy::FILES_ALLOW_ANY,
+                     sProfileDir, u"\\shader-cache\\*"_ns);
+  }
+}
+
+#define SANDBOX_ENSURE_SUCCESS(result, message)          \
+  do {                                                   \
+    MOZ_ASSERT(sandbox::SBOX_ALL_OK == result, message); \
+    if (sandbox::SBOX_ALL_OK != result) return false;    \
+  } while (0)
+
+bool SandboxBroker::SetSecurityLevelForRDDProcess() {
+  if (!mPolicy) {
+    return false;
+  }
+
+  auto result =
+      mPolicy->SetJobLevel(sandbox::JOB_LOCKDOWN, 0 /* ui_exceptions */);
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "SetJobLevel should never fail with these arguments, what happened?");
+
+  result = mPolicy->SetTokenLevel(sandbox::USER_RESTRICTED_SAME_ACCESS,
+                                  sandbox::USER_LIMITED);
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "SetTokenLevel should never fail with these arguments, what happened?");
+
+  result = mPolicy->SetAlternateDesktop(true);
+  if (NS_WARN_IF(result != sandbox::SBOX_ALL_OK)) {
+    LOG_W("SetAlternateDesktop failed, result: %i, last error: %lx", result,
+          ::GetLastError());
+  }
+
+  result = mPolicy->SetIntegrityLevel(sandbox::INTEGRITY_LEVEL_LOW);
+  SANDBOX_ENSURE_SUCCESS(result,
+                         "SetIntegrityLevel should never fail with these "
+                         "arguments, what happened?");
+
+  result = mPolicy->SetDelayedIntegrityLevel(sandbox::INTEGRITY_LEVEL_LOW);
+  SANDBOX_ENSURE_SUCCESS(result,
+                         "SetDelayedIntegrityLevel should never fail with "
+                         "these arguments, what happened?");
+
+  mPolicy->SetLockdownDefaultDacl();
+  mPolicy->AddRestrictingRandomSid();
+
+  sandbox::MitigationFlags mitigations =
+      sandbox::MITIGATION_BOTTOM_UP_ASLR | sandbox::MITIGATION_HEAP_TERMINATE |
+      sandbox::MITIGATION_SEHOP | sandbox::MITIGATION_EXTENSION_POINT_DISABLE |
+      sandbox::MITIGATION_DEP_NO_ATL_THUNK | sandbox::MITIGATION_DEP |
+      sandbox::MITIGATION_NONSYSTEM_FONT_DISABLE |
+      sandbox::MITIGATION_IMAGE_LOAD_NO_REMOTE |
+      sandbox::MITIGATION_IMAGE_LOAD_NO_LOW_LABEL |
+      sandbox::MITIGATION_IMAGE_LOAD_PREFER_SYS32;
+
+  if (StaticPrefs::security_sandbox_rdd_shadow_stack_enabled()) {
+    mitigations |= sandbox::MITIGATION_CET_COMPAT_MODE;
+  }
+
+  result = mPolicy->SetProcessMitigations(mitigations);
+  SANDBOX_ENSURE_SUCCESS(result, "Invalid flags for SetProcessMitigations.");
+
+  mitigations = sandbox::MITIGATION_STRICT_HANDLE_CHECKS |
+                sandbox::MITIGATION_DLL_SEARCH_ORDER;
+
+  if (StaticPrefs::security_sandbox_rdd_acg_enabled()) {
+    // The RDD process depends on msmpeg2vdec.dll.
+    mitigations |= DynamicCodeFlagForSystemMediaLibraries();
+  }
+
+  result = mPolicy->SetDelayedProcessMitigations(mitigations);
+  SANDBOX_ENSURE_SUCCESS(result,
+                         "Invalid flags for SetDelayedProcessMitigations.");
+
+  result = AddCigToPolicy(mPolicy);
+  SANDBOX_ENSURE_SUCCESS(result, "Failed to initialize signed policy rules.");
+
+  // Add the policy for the client side of a pipe. It is just a file
+  // in the \pipe\ namespace. We restrict it to pipes that start with
+  // "chrome." so the sandboxed process cannot connect to system services.
+  result = mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                            sandbox::TargetPolicy::FILES_ALLOW_ANY,
+                            L"\\??\\pipe\\chrome.*");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  // Add the policy for the client side of the crash server pipe.
+  result = mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                            sandbox::TargetPolicy::FILES_ALLOW_ANY,
+                            L"\\??\\pipe\\gecko-crash-server-pipe.*");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  return true;
+}
+
+bool SandboxBroker::SetSecurityLevelForSocketProcess() {
+  if (!mPolicy) {
+    return false;
+  }
+
+  auto result =
+      mPolicy->SetJobLevel(sandbox::JOB_LOCKDOWN, 0 /* ui_exceptions */);
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "SetJobLevel should never fail with these arguments, what happened?");
+
+  result = mPolicy->SetTokenLevel(sandbox::USER_RESTRICTED_SAME_ACCESS,
+                                  sandbox::USER_LIMITED);
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "SetTokenLevel should never fail with these arguments, what happened?");
+
+  result = mPolicy->SetAlternateDesktop(true);
+  if (NS_WARN_IF(result != sandbox::SBOX_ALL_OK)) {
+    LOG_W("SetAlternateDesktop failed, result: %i, last error: %lx", result,
+          ::GetLastError());
+  }
+
+  result = mPolicy->SetIntegrityLevel(sandbox::INTEGRITY_LEVEL_LOW);
+  SANDBOX_ENSURE_SUCCESS(result,
+                         "SetIntegrityLevel should never fail with these "
+                         "arguments, what happened?");
+
+  result =
+      mPolicy->SetDelayedIntegrityLevel(sandbox::INTEGRITY_LEVEL_UNTRUSTED);
+  SANDBOX_ENSURE_SUCCESS(result,
+                         "SetDelayedIntegrityLevel should never fail with "
+                         "these arguments, what happened?");
+
+  mPolicy->SetLockdownDefaultDacl();
+  mPolicy->AddRestrictingRandomSid();
+
+  sandbox::MitigationFlags mitigations =
+      sandbox::MITIGATION_BOTTOM_UP_ASLR | sandbox::MITIGATION_HEAP_TERMINATE |
+      sandbox::MITIGATION_SEHOP | sandbox::MITIGATION_EXTENSION_POINT_DISABLE |
+      sandbox::MITIGATION_DEP_NO_ATL_THUNK | sandbox::MITIGATION_DEP |
+      sandbox::MITIGATION_NONSYSTEM_FONT_DISABLE |
+      sandbox::MITIGATION_IMAGE_LOAD_NO_REMOTE |
+      sandbox::MITIGATION_IMAGE_LOAD_NO_LOW_LABEL |
+      sandbox::MITIGATION_IMAGE_LOAD_PREFER_SYS32;
+
+  if (StaticPrefs::security_sandbox_socket_shadow_stack_enabled()) {
+    mitigations |= sandbox::MITIGATION_CET_COMPAT_MODE;
+  }
+
+  result = mPolicy->SetProcessMitigations(mitigations);
+  SANDBOX_ENSURE_SUCCESS(result, "Invalid flags for SetProcessMitigations.");
+
+  if (StaticPrefs::security_sandbox_socket_win32k_disable()) {
+    result = AddWin32kLockdownPolicy(mPolicy, false);
+    SANDBOX_ENSURE_SUCCESS(result, "Failed to add the win32k lockdown policy");
+  }
+
+  mitigations = sandbox::MITIGATION_STRICT_HANDLE_CHECKS |
+                sandbox::MITIGATION_DLL_SEARCH_ORDER |
+                sandbox::MITIGATION_DYNAMIC_CODE_DISABLE;
+
+  result = mPolicy->SetDelayedProcessMitigations(mitigations);
+  SANDBOX_ENSURE_SUCCESS(result,
+                         "Invalid flags for SetDelayedProcessMitigations.");
+
+  result = AddCigToPolicy(mPolicy);
+  SANDBOX_ENSURE_SUCCESS(result, "Failed to initialize signed policy rules.");
+
+  // Add the policy for the client side of a pipe. It is just a file
+  // in the \pipe\ namespace. We restrict it to pipes that start with
+  // "chrome." so the sandboxed process cannot connect to system services.
+  result = mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                            sandbox::TargetPolicy::FILES_ALLOW_ANY,
+                            L"\\??\\pipe\\chrome.*");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  // Add the policy for the client side of the crash server pipe.
+  result = mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                            sandbox::TargetPolicy::FILES_ALLOW_ANY,
+                            L"\\??\\pipe\\gecko-crash-server-pipe.*");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  return true;
+}
+
+// A strict base sandbox for utility sandboxes to adapt.
+struct UtilitySandboxProps {
+  sandbox::JobLevel mJobLevel = sandbox::JOB_LOCKDOWN;
+
+  sandbox::TokenLevel mInitialTokenLevel = sandbox::USER_RESTRICTED_SAME_ACCESS;
+  sandbox::TokenLevel mDelayedTokenLevel = sandbox::USER_LOCKDOWN;
+
+  sandbox::IntegrityLevel mInitialIntegrityLevel =  // before lockdown
+      sandbox::INTEGRITY_LEVEL_LOW;
+  sandbox::IntegrityLevel mDelayedIntegrityLevel =  // after lockdown
+      sandbox::INTEGRITY_LEVEL_UNTRUSTED;
+
+  bool mUseAlternateWindowStation = true;
+  bool mUseAlternateDesktop = true;
+  bool mLockdownDefaultDacl = true;
+  bool mAddRestrictingRandomSid = true;
+  bool mUseWin32kLockdown = true;
+  bool mUseCig = true;
+
+  sandbox::MitigationFlags mInitialMitigations =
+      sandbox::MITIGATION_BOTTOM_UP_ASLR | sandbox::MITIGATION_HEAP_TERMINATE |
+      sandbox::MITIGATION_SEHOP | sandbox::MITIGATION_EXTENSION_POINT_DISABLE |
+      sandbox::MITIGATION_DEP_NO_ATL_THUNK | sandbox::MITIGATION_DEP |
+      sandbox::MITIGATION_NONSYSTEM_FONT_DISABLE |
+      sandbox::MITIGATION_IMAGE_LOAD_NO_REMOTE |
+      sandbox::MITIGATION_IMAGE_LOAD_NO_LOW_LABEL |
+      sandbox::MITIGATION_IMAGE_LOAD_PREFER_SYS32 |
+      sandbox::MITIGATION_CET_COMPAT_MODE;
+
+  sandbox::MitigationFlags mDelayedMitigations =
+      sandbox::MITIGATION_STRICT_HANDLE_CHECKS |
+      sandbox::MITIGATION_DLL_SEARCH_ORDER |
+      sandbox::MITIGATION_DYNAMIC_CODE_DISABLE;
+
+  // Low Privileged Application Container settings;
+  nsString mPackagePrefix;
+  nsTArray<sandbox::WellKnownCapabilities> mWellKnownCapabilites;
+  nsTArray<const wchar_t*> mNamedCapabilites;
+};
+
+struct GenericUtilitySandboxProps : public UtilitySandboxProps {};
+
+struct UtilityAudioDecodingWmfSandboxProps : public UtilitySandboxProps {
+  UtilityAudioDecodingWmfSandboxProps() {
+    mDelayedTokenLevel = sandbox::USER_LIMITED;
+    mDelayedMitigations = sandbox::MITIGATION_STRICT_HANDLE_CHECKS |
+                          sandbox::MITIGATION_DLL_SEARCH_ORDER;
+#ifdef MOZ_WMF
+    if (StaticPrefs::security_sandbox_utility_wmf_acg_enabled()) {
+      mDelayedMitigations |= DynamicCodeFlagForSystemMediaLibraries();
+    }
+#else
+    mDelayedMitigations |= sandbox::MITIGATION_DYNAMIC_CODE_DISABLE;
+#endif  // MOZ_WMF
+  }
+};
+
+#ifdef MOZ_WMF_MEDIA_ENGINE
+struct UtilityMfMediaEngineCdmSandboxProps : public UtilitySandboxProps {
+  UtilityMfMediaEngineCdmSandboxProps() {
+    mJobLevel = sandbox::JOB_INTERACTIVE;
+    mInitialTokenLevel = sandbox::USER_UNPROTECTED;
+    mDelayedTokenLevel = sandbox::USER_UNPROTECTED;
+    mUseAlternateDesktop = false;
+    mUseAlternateWindowStation = false;
+    mLockdownDefaultDacl = false;
+    mAddRestrictingRandomSid = false;
+    mUseCig = false;
+
+    // When we have an LPAC we can't set an integrity level and the process will
+    // default to low integrity anyway. Without an LPAC using low integrity
+    // causes problems with the CDMs.
+    mInitialIntegrityLevel = sandbox::INTEGRITY_LEVEL_LAST;
+    mDelayedIntegrityLevel = sandbox::INTEGRITY_LEVEL_LAST;
+
+    if (StaticPrefs::security_sandbox_utility_wmf_cdm_lpac_enabled()) {
+      mPackagePrefix = u"fx.sb.cdm"_ns;
+      mWellKnownCapabilites = {
+          sandbox::WellKnownCapabilities::kPrivateNetworkClientServer,
+          sandbox::WellKnownCapabilities::kInternetClient,
+      };
+      mNamedCapabilites = {
+          L"lpacCom",
+          L"lpacIdentityServices",
+          L"lpacMedia",
+          L"lpacPnPNotifications",
+          L"lpacServicesManagement",
+          L"lpacSessionManagement",
+          L"lpacAppExperience",
+          L"lpacInstrumentation",
+          L"lpacCryptoServices",
+          L"lpacEnterprisePolicyChangeNotifications",
+          L"mediaFoundationCdmFiles",
+          L"lpacMediaFoundationCdmData",
+          L"registryRead",
+          kLpacFirefoxInstallFiles,
+          L"lpacDeviceAccess",
+      };
+
+      // For MSIX packages we need access to the package contents.
+      if (widget::WinUtils::HasPackageIdentity()) {
+        mNamedCapabilites.AppendElement(L"packageContents");
+      }
+    }
+    mUseWin32kLockdown = false;
+    mDelayedMitigations = sandbox::MITIGATION_DLL_SEARCH_ORDER;
+  }
+};
+#endif
+
+struct WindowsUtilitySandboxProps : public UtilitySandboxProps {
+  WindowsUtilitySandboxProps() {
+    mJobLevel = sandbox::JOB_INTERACTIVE;
+    mDelayedTokenLevel = sandbox::USER_RESTRICTED_SAME_ACCESS;
+    mUseAlternateWindowStation = false;
+    mInitialIntegrityLevel = sandbox::INTEGRITY_LEVEL_MEDIUM;
+    mDelayedIntegrityLevel = sandbox::INTEGRITY_LEVEL_MEDIUM;
+    mUseWin32kLockdown = false;
+    mUseCig = false;
+    mDelayedMitigations = sandbox::MITIGATION_STRICT_HANDLE_CHECKS |
+                          sandbox::MITIGATION_DLL_SEARCH_ORDER;
+  }
+};
+
+static const char* WellKnownCapabilityNames[] = {
+    "InternetClient",
+    "InternetClientServer",
+    "PrivateNetworkClientServer",
+    "PicturesLibrary",
+    "VideosLibrary",
+    "MusicLibrary",
+    "DocumentsLibrary",
+    "EnterpriseAuthentication",
+    "SharedUserCertificates",
+    "RemovableStorage",
+    "Appointments",
+    "Contacts",
+};
+
+void LogUtilitySandboxProps(const UtilitySandboxProps& us) {
+  if (!static_cast<LogModule*>(sSandboxBrokerLog)->ShouldLog(LogLevel::Debug)) {
+    return;
+  }
+
+  nsAutoCString logMsg;
+  logMsg.AppendPrintf("Building sandbox for utility process:\n");
+  logMsg.AppendPrintf("\tJob Level: %d\n", static_cast<int>(us.mJobLevel));
+  logMsg.AppendPrintf("\tInitial Token Level: %d\n",
+                      static_cast<int>(us.mInitialTokenLevel));
+  logMsg.AppendPrintf("\tDelayed Token Level: %d\n",
+                      static_cast<int>(us.mDelayedTokenLevel));
+  logMsg.AppendPrintf("\tInitial Integrity Level: %d\n",
+                      static_cast<int>(us.mInitialIntegrityLevel));
+  logMsg.AppendPrintf("\tDelayed Integrity Level: %d\n",
+                      static_cast<int>(us.mDelayedIntegrityLevel));
+  logMsg.AppendPrintf("\tUse Alternate Window Station: %s\n",
+                      us.mUseAlternateWindowStation ? "yes" : "no");
+  logMsg.AppendPrintf("\tUse Alternate Desktop: %s\n",
+                      us.mUseAlternateDesktop ? "yes" : "no");
+  logMsg.AppendPrintf("\tLockdown Default Dacl: %s\n",
+                      us.mLockdownDefaultDacl ? "yes" : "no");
+  logMsg.AppendPrintf("\tAdd Random Restricting SID: %s\n",
+                      us.mAddRestrictingRandomSid ? "yes" : "no");
+  logMsg.AppendPrintf("\tUse Win32k Lockdown: %s\n",
+                      us.mUseWin32kLockdown ? "yes" : "no");
+  logMsg.AppendPrintf("\tUse CIG: %s\n", us.mUseCig ? "yes" : "no");
+  logMsg.AppendPrintf("\tInitial mitigations: %016llx\n",
+                      static_cast<uint64_t>(us.mInitialMitigations));
+  logMsg.AppendPrintf("\tDelayed mitigations: %016llx\n",
+                      static_cast<uint64_t>(us.mDelayedMitigations));
+  if (us.mPackagePrefix.IsEmpty()) {
+    logMsg.AppendPrintf("\tNo Low Privileged Application Container\n");
+  } else {
+    logMsg.AppendPrintf("\tLow Privileged Application Container Settings:\n");
+    logMsg.AppendPrintf("\t\tPackage Name Prefix: %S\n",
+                        static_cast<wchar_t*>(us.mPackagePrefix.get()));
+    logMsg.AppendPrintf("\t\tWell Known Capabilities:\n");
+    for (auto wkCap : us.mWellKnownCapabilites) {
+      logMsg.AppendPrintf("\t\t\t%s\n", WellKnownCapabilityNames[wkCap]);
+    }
+    logMsg.AppendPrintf("\t\tNamed Capabilities:\n");
+    for (auto namedCap : us.mNamedCapabilites) {
+      logMsg.AppendPrintf("\t\t\t%S\n", namedCap);
+    }
+  }
+
+  LOG_D("%s", logMsg.get());
+}
+
+bool BuildUtilitySandbox(sandbox::TargetPolicy* policy,
+                         const UtilitySandboxProps& us) {
+  LogUtilitySandboxProps(us);
+
+  auto result = policy->SetJobLevel(us.mJobLevel, 0 /* ui_exceptions */);
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "SetJobLevel should never fail with these arguments, what happened?");
+
+  result = policy->SetTokenLevel(us.mInitialTokenLevel, us.mDelayedTokenLevel);
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "SetTokenLevel should never fail with these arguments, what happened?");
+
+  if (us.mInitialIntegrityLevel != sandbox::INTEGRITY_LEVEL_LAST) {
+    result = policy->SetIntegrityLevel(us.mInitialIntegrityLevel);
+    SANDBOX_ENSURE_SUCCESS(result,
+                           "SetIntegrityLevel should never fail with these "
+                           "arguments, what happened?");
+  }
+
+  if (us.mDelayedIntegrityLevel != sandbox::INTEGRITY_LEVEL_LAST) {
+    result = policy->SetDelayedIntegrityLevel(us.mDelayedIntegrityLevel);
+    SANDBOX_ENSURE_SUCCESS(result,
+                           "SetIntegrityLevel should never fail with these "
+                           "arguments, what happened?");
+  }
+
+  if (us.mUseAlternateDesktop) {
+    result = policy->SetAlternateDesktop(us.mUseAlternateWindowStation);
+    if (NS_WARN_IF(result != sandbox::SBOX_ALL_OK)) {
+      LOG_W("SetAlternateDesktop failed, result: %i, last error: %lx", result,
+            ::GetLastError());
+    }
+  }
+
+  if (us.mLockdownDefaultDacl) {
+    policy->SetLockdownDefaultDacl();
+  }
+  if (us.mAddRestrictingRandomSid) {
+    policy->AddRestrictingRandomSid();
+  }
+
+  result = policy->SetProcessMitigations(us.mInitialMitigations);
+  SANDBOX_ENSURE_SUCCESS(result, "Invalid flags for SetProcessMitigations.");
+
+  result = policy->SetDelayedProcessMitigations(us.mDelayedMitigations);
+  SANDBOX_ENSURE_SUCCESS(result,
+                         "Invalid flags for SetDelayedProcessMitigations.");
+
+  // Win32k lockdown might not work on earlier versions
+  // Bug 1719212, 1769992
+  if (us.mUseWin32kLockdown && IsWin10FallCreatorsUpdateOrLater()) {
+    result = AddWin32kLockdownPolicy(policy, false);
+    SANDBOX_ENSURE_SUCCESS(result, "Failed to add the win32k lockdown policy");
+  }
+
+  if (us.mUseCig) {
+    bool alwaysProxyBinDirLoading = mozilla::HasPackageIdentity();
+    result = AddCigToPolicy(policy, alwaysProxyBinDirLoading);
+    SANDBOX_ENSURE_SUCCESS(result, "Failed to initialize signed policy rules.");
+  }
+
+  // Process fails to start in LPAC with ASan build
+#if !defined(MOZ_ASAN)
+  if (!us.mPackagePrefix.IsEmpty()) {
+    MOZ_ASSERT(us.mInitialIntegrityLevel == sandbox::INTEGRITY_LEVEL_LAST,
+               "Initial integrity level cannot be specified if using an LPAC.");
+
+    result = AddAndConfigureAppContainerProfile(policy, us.mPackagePrefix,
+                                                us.mWellKnownCapabilites,
+                                                us.mNamedCapabilites);
+    SANDBOX_ENSURE_SUCCESS(result, "Failed to configure AppContainer profile.");
+  }
+#endif
+
+  // Add the policy for the client side of a pipe. It is just a file
+  // in the \pipe\ namespace. We restrict it to pipes that start with
+  // "chrome." so the sandboxed process cannot connect to system services.
+  result = policy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                           sandbox::TargetPolicy::FILES_ALLOW_ANY,
+                           L"\\??\\pipe\\chrome.*");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  // Add the policy for the client side of the crash server pipe.
+  result = policy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                           sandbox::TargetPolicy::FILES_ALLOW_ANY,
+                           L"\\??\\pipe\\gecko-crash-server-pipe.*");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  return true;
+}
+
+bool SandboxBroker::SetSecurityLevelForUtilityProcess(
+    mozilla::ipc::SandboxingKind aSandbox) {
+  if (!mPolicy) {
+    return false;
+  }
+
+  switch (aSandbox) {
+    case mozilla::ipc::SandboxingKind::GENERIC_UTILITY:
+      return BuildUtilitySandbox(mPolicy, GenericUtilitySandboxProps());
+    case mozilla::ipc::SandboxingKind::UTILITY_AUDIO_DECODING_WMF:
+      return BuildUtilitySandbox(mPolicy,
+                                 UtilityAudioDecodingWmfSandboxProps());
+#ifdef MOZ_WMF_MEDIA_ENGINE
+    case mozilla::ipc::SandboxingKind::MF_MEDIA_ENGINE_CDM:
+      return BuildUtilitySandbox(mPolicy,
+                                 UtilityMfMediaEngineCdmSandboxProps());
+#endif
+    case mozilla::ipc::SandboxingKind::WINDOWS_UTILS:
+      return BuildUtilitySandbox(mPolicy, WindowsUtilitySandboxProps());
+    case mozilla::ipc::SandboxingKind::WINDOWS_FILE_DIALOG:
+      // This process type is not sandboxed. (See commentary in
+      // `ipc::IsUtilitySandboxEnabled()`.)
+      MOZ_ASSERT_UNREACHABLE("No sandboxing for this process type");
+      return false;
+    default:
+      MOZ_ASSERT_UNREACHABLE("Unknown sandboxing value");
+      return false;
+  }
+}
+
+bool SandboxBroker::SetSecurityLevelForGMPlugin(SandboxLevel aLevel,
+                                                bool aIsRemoteLaunch) {
+  if (!mPolicy) {
+    return false;
+  }
+
+  auto result =
+      mPolicy->SetJobLevel(sandbox::JOB_LOCKDOWN, 0 /* ui_exceptions */);
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "SetJobLevel should never fail with these arguments, what happened?");
+  auto level = (aLevel == Restricted) ? sandbox::USER_RESTRICTED
+                                      : sandbox::USER_LOCKDOWN;
+  result = mPolicy->SetTokenLevel(sandbox::USER_RESTRICTED_SAME_ACCESS, level);
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "SetTokenLevel should never fail with these arguments, what happened?");
+
+  result = mPolicy->SetAlternateDesktop(true);
+  if (NS_WARN_IF(result != sandbox::SBOX_ALL_OK)) {
+    LOG_W("SetAlternateDesktop failed, result: %i, last error: %lx", result,
+          ::GetLastError());
+  }
+
+  result = mPolicy->SetIntegrityLevel(sandbox::INTEGRITY_LEVEL_LOW);
+  MOZ_ASSERT(sandbox::SBOX_ALL_OK == result,
+             "SetIntegrityLevel should never fail with these arguments, what "
+             "happened?");
+
+  result =
+      mPolicy->SetDelayedIntegrityLevel(sandbox::INTEGRITY_LEVEL_UNTRUSTED);
+  SANDBOX_ENSURE_SUCCESS(result,
+                         "SetIntegrityLevel should never fail with these "
+                         "arguments, what happened?");
+
+  mPolicy->SetLockdownDefaultDacl();
+  mPolicy->AddRestrictingRandomSid();
+
+  sandbox::MitigationFlags mitigations =
+      sandbox::MITIGATION_BOTTOM_UP_ASLR | sandbox::MITIGATION_HEAP_TERMINATE |
+      sandbox::MITIGATION_SEHOP | sandbox::MITIGATION_EXTENSION_POINT_DISABLE |
+      sandbox::MITIGATION_NONSYSTEM_FONT_DISABLE |
+      sandbox::MITIGATION_IMAGE_LOAD_NO_REMOTE |
+      sandbox::MITIGATION_IMAGE_LOAD_NO_LOW_LABEL |
+      sandbox::MITIGATION_DEP_NO_ATL_THUNK | sandbox::MITIGATION_DEP;
+
+  if (StaticPrefs::security_sandbox_gmp_shadow_stack_enabled()) {
+    mitigations |= sandbox::MITIGATION_CET_COMPAT_MODE;
+  }
+
+  result = mPolicy->SetProcessMitigations(mitigations);
+  SANDBOX_ENSURE_SUCCESS(result, "Invalid flags for SetProcessMitigations.");
+
+  if (StaticPrefs::security_sandbox_gmp_win32k_disable()) {
+    result = AddWin32kLockdownPolicy(mPolicy, true);
+    SANDBOX_ENSURE_SUCCESS(result, "Failed to add the win32k lockdown policy");
+  }
+
+  mitigations = sandbox::MITIGATION_STRICT_HANDLE_CHECKS |
+                sandbox::MITIGATION_DLL_SEARCH_ORDER;
+
+  result = mPolicy->SetDelayedProcessMitigations(mitigations);
+  SANDBOX_ENSURE_SUCCESS(result,
+                         "Invalid flags for SetDelayedProcessMitigations.");
+
+  // Add the policy for the client side of a pipe. It is just a file
+  // in the \pipe\ namespace. We restrict it to pipes that start with
+  // "chrome." so the sandboxed process cannot connect to system services.
+  result = mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                            sandbox::TargetPolicy::FILES_ALLOW_ANY,
+                            L"\\??\\pipe\\chrome.*");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  // Add the policy for the client side of the crash server pipe.
+  result = mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                            sandbox::TargetPolicy::FILES_ALLOW_ANY,
+                            L"\\??\\pipe\\gecko-crash-server-pipe.*");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+#ifdef DEBUG
+  // The plugin process can't create named events, but we'll
+  // make an exception for the events used in logging. Removing
+  // this will break EME in debug builds.
+  result = mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_SYNC,
+                            sandbox::TargetPolicy::EVENTS_ALLOW_ANY,
+                            L"ChromeIPCLog.*");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+#endif
+
+  // The following rules were added because, during analysis of an EME
+  // plugin during development, these registry keys were accessed when
+  // loading the plugin. Commenting out these policy exceptions caused
+  // plugin loading to fail, so they are necessary for proper functioning
+  // of at least one EME plugin.
+  result = mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_REGISTRY,
+                            sandbox::TargetPolicy::REG_ALLOW_READONLY,
+                            L"HKEY_CURRENT_USER");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  result = mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_REGISTRY,
+                            sandbox::TargetPolicy::REG_ALLOW_READONLY,
+                            L"HKEY_CURRENT_USER\\Control Panel\\Desktop");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  result = mPolicy->AddRule(
+      sandbox::TargetPolicy::SUBSYS_REGISTRY,
+      sandbox::TargetPolicy::REG_ALLOW_READONLY,
+      L"HKEY_CURRENT_USER\\Control Panel\\Desktop\\LanguageConfiguration");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  result = mPolicy->AddRule(
+      sandbox::TargetPolicy::SUBSYS_REGISTRY,
+      sandbox::TargetPolicy::REG_ALLOW_READONLY,
+      L"HKEY_LOCAL_"
+      L"MACHINE\\SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\SideBySide");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  // The following rules were added because, during analysis of an EME
+  // plugin during development, these registry keys were accessed when
+  // loading the plugin. Commenting out these policy exceptions did not
+  // cause anything to break during initial testing, but might cause
+  // unforeseen issues down the road.
+  result = mPolicy->AddRule(
+      sandbox::TargetPolicy::SUBSYS_REGISTRY,
+      sandbox::TargetPolicy::REG_ALLOW_READONLY,
+      L"HKEY_LOCAL_MACHINE\\SOFTWARE\\Policies\\Microsoft\\MUI\\Settings");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  result = mPolicy->AddRule(
+      sandbox::TargetPolicy::SUBSYS_REGISTRY,
+      sandbox::TargetPolicy::REG_ALLOW_READONLY,
+      L"HKEY_CURRENT_USER\\Software\\Policies\\Microsoft\\Control "
+      L"Panel\\Desktop");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  result = mPolicy->AddRule(
+      sandbox::TargetPolicy::SUBSYS_REGISTRY,
+      sandbox::TargetPolicy::REG_ALLOW_READONLY,
+      L"HKEY_CURRENT_USER\\Control Panel\\Desktop\\PreferredUILanguages");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  result = mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_REGISTRY,
+                            sandbox::TargetPolicy::REG_ALLOW_READONLY,
+                            L"HKEY_LOCAL_"
+                            L"MACHINE\\SOFTWARE\\Microsoft\\Windows\\CurrentVer"
+                            L"sion\\SideBySide\\PreferExternalManifest");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  // The following rules were added to allow a GMP to be loaded when any
+  // AppLocker DLL rules are specified. If the rules specifically block the DLL
+  // then it will not load.
+  result = mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                            sandbox::TargetPolicy::FILES_ALLOW_READONLY,
+                            L"\\Device\\SrpDevice");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+  result = mPolicy->AddRule(
+      sandbox::TargetPolicy::SUBSYS_REGISTRY,
+      sandbox::TargetPolicy::REG_ALLOW_READONLY,
+      L"HKEY_LOCAL_MACHINE\\System\\CurrentControlSet\\Control\\Srp\\GP\\");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+  // On certain Windows versions there is a double slash before GP in the path.
+  result = mPolicy->AddRule(
+      sandbox::TargetPolicy::SUBSYS_REGISTRY,
+      sandbox::TargetPolicy::REG_ALLOW_READONLY,
+      L"HKEY_LOCAL_MACHINE\\System\\CurrentControlSet\\Control\\Srp\\\\GP\\");
+  SANDBOX_ENSURE_SUCCESS(
+      result,
+      "With these static arguments AddRule should never fail, what happened?");
+
+  return true;
+}
+#undef SANDBOX_ENSURE_SUCCESS
+
+bool SandboxBroker::AllowReadFile(wchar_t const* file) {
+  if (!mPolicy) {
+    return false;
+  }
+
+  auto result =
+      mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_FILES,
+                       sandbox::TargetPolicy::FILES_ALLOW_READONLY, file);
+  if (sandbox::SBOX_ALL_OK != result) {
+    LOG_E("Failed (ResultCode %d) to add read access to: %S", result, file);
+    return false;
+  }
+
+  return true;
+}
+
+void SandboxBroker::AddHandleToShare(HANDLE aHandle) {
+  mPolicy->AddHandleToShare(aHandle);
+}
+
+bool SandboxBroker::IsWin32kLockedDown() {
+  return mPolicy->GetProcessMitigations() & sandbox::MITIGATION_WIN32K_DISABLE;
+}
+
+void SandboxBroker::ApplyLoggingPolicy() {
+  MOZ_ASSERT(mPolicy);
+
+  // Add dummy rules, so that we can log in the interception code.
+  // We already have a file interception set up for the client side of pipes.
+  // Also, passing just "dummy" for file system policy causes win_utils.cc
+  // IsReparsePoint() to loop.
+  mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_NAMED_PIPES,
+                   sandbox::TargetPolicy::NAMEDPIPES_ALLOW_ANY, L"dummy");
+  mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_PROCESS,
+                   sandbox::TargetPolicy::PROCESS_MIN_EXEC, L"dummy");
+  mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_REGISTRY,
+                   sandbox::TargetPolicy::REG_ALLOW_READONLY,
+                   L"HKEY_CURRENT_USER\\dummy");
+  mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_SYNC,
+                   sandbox::TargetPolicy::EVENTS_ALLOW_READONLY, L"dummy");
+  mPolicy->AddRule(sandbox::TargetPolicy::SUBSYS_HANDLES,
+                   sandbox::TargetPolicy::HANDLES_DUP_BROKER, L"dummy");
+}
+
+SandboxBroker::~SandboxBroker() {
+  if (mPolicy) {
+    mPolicy->Release();
+    mPolicy = nullptr;
+  }
+}
+
+}  // namespace mozilla
diff --git a/security/sandbox/win/src/sandboxbroker/sandboxBroker.h b/security/sandbox/win/src/sandboxbroker/sandboxBroker.h
new file mode 100644
index 0000000000..45a0cbb38b
--- /dev/null
+++ b/security/sandbox/win/src/sandboxbroker/sandboxBroker.h
@@ -0,0 +1,132 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#ifndef __SECURITY_SANDBOX_SANDBOXBROKER_H__
+#define __SECURITY_SANDBOX_SANDBOXBROKER_H__
+
+#include <stdint.h>
+#include <windows.h>
+
+#include "mozilla/ipc/EnvironmentMap.h"
+#include "nsCOMPtr.h"
+#include "nsXULAppAPI.h"
+#include "nsISupportsImpl.h"
+
+#include "mozilla/ipc/UtilityProcessSandboxing.h"
+#include "mozilla/ipc/LaunchError.h"
+#include "mozilla/Result.h"
+
+namespace sandbox {
+class BrokerServices;
+class TargetPolicy;
+}  // namespace sandbox
+
+namespace mozilla {
+
+class AbstractSandboxBroker {
+ public:
+  NS_INLINE_DECL_THREADSAFE_REFCOUNTING(AbstractSandboxBroker)
+
+  virtual void Shutdown() = 0;
+  virtual Result<Ok, mozilla::ipc::LaunchError> LaunchApp(
+      const wchar_t* aPath, const wchar_t* aArguments,
+      base::EnvironmentMap& aEnvironment, GeckoProcessType aProcessType,
+      const bool aEnableLogging, const IMAGE_THUNK_DATA* aCachedNtdllThunk,
+      void** aProcessHandle) = 0;
+
+  // Security levels for different types of processes
+  virtual void SetSecurityLevelForContentProcess(int32_t aSandboxLevel,
+                                                 bool aIsFileProcess) = 0;
+
+  virtual void SetSecurityLevelForGPUProcess(int32_t aSandboxLevel) = 0;
+  virtual bool SetSecurityLevelForRDDProcess() = 0;
+  virtual bool SetSecurityLevelForSocketProcess() = 0;
+  virtual bool SetSecurityLevelForUtilityProcess(
+      mozilla::ipc::SandboxingKind aSandbox) = 0;
+
+  enum SandboxLevel { LockDown, Restricted };
+  virtual bool SetSecurityLevelForGMPlugin(SandboxLevel aLevel,
+                                           bool aIsRemoteLaunch = false) = 0;
+
+  // File system permissions
+  virtual bool AllowReadFile(wchar_t const* file) = 0;
+
+  /**
+   * Share a HANDLE with the child process. The HANDLE will be made available
+   * in the child process at the memory address
+   * |reinterpret_cast<uintptr_t>(aHandle)|. It is the caller's responsibility
+   * to communicate this address to the child.
+   */
+  virtual void AddHandleToShare(HANDLE aHandle) = 0;
+
+  /**
+   * @return true if policy has win32k locked down, otherwise false
+   */
+  virtual bool IsWin32kLockedDown() = 0;
+
+ protected:
+  virtual ~AbstractSandboxBroker() {}
+};
+
+class SandboxBroker : public AbstractSandboxBroker {
+ public:
+  SandboxBroker();
+
+  static void Initialize(sandbox::BrokerServices* aBrokerServices);
+
+  static void EnsureLpacPermsissionsOnDir(const nsString& aDir);
+
+  void Shutdown() override {}
+
+  /**
+   * Do initialization that depends on parts of the Gecko machinery having been
+   * created first.
+   */
+  static void GeckoDependentInitialize();
+
+  Result<Ok, mozilla::ipc::LaunchError> LaunchApp(
+      const wchar_t* aPath, const wchar_t* aArguments,
+      base::EnvironmentMap& aEnvironment, GeckoProcessType aProcessType,
+      const bool aEnableLogging, const IMAGE_THUNK_DATA* aCachedNtdllThunk,
+      void** aProcessHandle) override;
+  virtual ~SandboxBroker();
+
+  // Security levels for different types of processes
+  void SetSecurityLevelForContentProcess(int32_t aSandboxLevel,
+                                         bool aIsFileProcess) override;
+
+  void SetSecurityLevelForGPUProcess(int32_t aSandboxLevel) override;
+  bool SetSecurityLevelForRDDProcess() override;
+  bool SetSecurityLevelForSocketProcess() override;
+  bool SetSecurityLevelForGMPlugin(SandboxLevel aLevel,
+                                   bool aIsRemoteLaunch = false) override;
+  bool SetSecurityLevelForUtilityProcess(
+      mozilla::ipc::SandboxingKind aSandbox) override;
+
+  // File system permissions
+  bool AllowReadFile(wchar_t const* file) override;
+
+  /**
+   * Share a HANDLE with the child process. The HANDLE will be made available
+   * in the child process at the memory address
+   * |reinterpret_cast<uintptr_t>(aHandle)|. It is the caller's responsibility
+   * to communicate this address to the child.
+   */
+  void AddHandleToShare(HANDLE aHandle) override;
+
+  bool IsWin32kLockedDown() final;
+
+  // Set up dummy interceptions via the broker, so we can log calls.
+  void ApplyLoggingPolicy();
+
+ private:
+  static bool sRunningFromNetworkDrive;
+  sandbox::TargetPolicy* mPolicy;
+};
+
+}  // namespace mozilla
+
+#endif
diff --git a/security/sandbox/win/src/sandboxtarget/moz.build b/security/sandbox/win/src/sandboxtarget/moz.build
new file mode 100644
index 0000000000..3c28eebba2
--- /dev/null
+++ b/security/sandbox/win/src/sandboxtarget/moz.build
@@ -0,0 +1,22 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# 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/.
+
+EXPORTS.mozilla += [
+    "sandboxTarget.h",
+]
+
+SOURCES += [
+    "sandboxTarget.cpp",
+]
+
+LOCAL_INCLUDES += [
+    "/security/sandbox/chromium",
+    "/security/sandbox/chromium-shim",
+]
+
+DEFINES["UNICODE"] = True
+
+FINAL_LIBRARY = "xul"
diff --git a/security/sandbox/win/src/sandboxtarget/sandboxTarget.cpp b/security/sandbox/win/src/sandboxtarget/sandboxTarget.cpp
new file mode 100644
index 0000000000..66497ce65d
--- /dev/null
+++ b/security/sandbox/win/src/sandboxtarget/sandboxTarget.cpp
@@ -0,0 +1,51 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 "sandboxTarget.h"
+
+#include "sandbox/win/src/sandbox.h"
+
+namespace mozilla {
+
+// We need to define this function out of line so that clang-cl doesn't inline
+// it.
+/* static */
+SandboxTarget* SandboxTarget::Instance() {
+  static SandboxTarget sb;
+  return &sb;
+}
+
+void SandboxTarget::StartSandbox() {
+  if (mTargetServices) {
+    mTargetServices->LowerToken();
+    NotifyStartObservers();
+  }
+}
+
+void SandboxTarget::NotifyStartObservers() {
+  for (auto&& obs : mStartObservers) {
+    if (!obs) {
+      continue;
+    }
+
+    obs();
+  }
+
+  mStartObservers.clear();
+}
+
+bool SandboxTarget::GetComplexLineBreaks(const WCHAR* text, uint32_t length,
+                                         uint8_t* break_before) {
+  if (!mTargetServices) {
+    return false;
+  }
+
+  sandbox::ResultCode result =
+      mTargetServices->GetComplexLineBreaks(text, length, break_before);
+  return (sandbox::SBOX_ALL_OK == result);
+}
+
+}  // namespace mozilla
diff --git a/security/sandbox/win/src/sandboxtarget/sandboxTarget.h b/security/sandbox/win/src/sandboxtarget/sandboxTarget.h
new file mode 100644
index 0000000000..1aab1ef76a
--- /dev/null
+++ b/security/sandbox/win/src/sandboxtarget/sandboxTarget.h
@@ -0,0 +1,72 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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/. */
+
+#ifndef __SECURITY_SANDBOX_SANDBOXTARGET_H__
+#define __SECURITY_SANDBOX_SANDBOXTARGET_H__
+
+#include <windows.h>
+
+#include <functional>
+#include <list>
+#include <utility>
+
+#include "mozilla/Assertions.h"
+
+namespace sandbox {
+class TargetServices;
+}
+
+namespace mozilla {
+
+class SandboxTarget {
+ public:
+  /**
+   * Obtains a pointer to the singleton instance
+   */
+  static SandboxTarget* Instance();
+
+  /**
+   * Used by the application to pass in the target services that provide certain
+   * functions to the sandboxed code.
+   * The target services must already be initialized.
+   *
+   * @param aTargetServices The target services that will be used
+   */
+  void SetTargetServices(sandbox::TargetServices* aTargetServices) {
+    MOZ_ASSERT(aTargetServices);
+    MOZ_ASSERT(!mTargetServices,
+               "Sandbox TargetServices must only be set once.");
+
+    mTargetServices = aTargetServices;
+  }
+
+  template <typename CallbackT>
+  void RegisterSandboxStartCallback(CallbackT&& aCallback) {
+    mStartObservers.push_back(std::forward<CallbackT>(aCallback));
+  }
+
+  /**
+   * Called by the library that wants to "start" the sandbox, i.e. change to the
+   * more secure delayed / lockdown policy.
+   */
+  void StartSandbox();
+
+  bool GetComplexLineBreaks(const WCHAR* text, uint32_t length,
+                            uint8_t* break_before);
+
+ protected:
+  SandboxTarget() : mTargetServices(nullptr) {}
+
+  sandbox::TargetServices* mTargetServices;
+
+ private:
+  void NotifyStartObservers();
+  std::list<std::function<void()>> mStartObservers;
+};
+
+}  // namespace mozilla
+
+#endif