1 files changed, 127 insertions, 0 deletions
diff --git a/ipc/mscom/PassthruProxy.h b/ipc/mscom/PassthruProxy.h
new file mode 100644
index 0000000000..afdb5c648e
--- /dev/null
+++ b/ipc/mscom/PassthruProxy.h
@@ -0,0 +1,127 @@
+/* -*- 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 mozilla_mscom_PassthruProxy_h
+#define mozilla_mscom_PassthruProxy_h
+
+#include "mozilla/Atomics.h"
+#include "mozilla/mscom/ProxyStream.h"
+#include "mozilla/mscom/Ptr.h"
+#include "mozilla/NotNull.h"
+#if defined(MOZ_SANDBOX)
+#  include "mozilla/SandboxSettings.h"
+#endif  // defined(MOZ_SANDBOX)
+
+#include <objbase.h>
+
+namespace mozilla {
+namespace mscom {
+namespace detail {
+
+template <typename Iface>
+struct VTableSizer;
+
+template <>
+struct VTableSizer<IDispatch> {
+  enum { Size = 7 };
+};
+
+}  // namespace detail
+
+class PassthruProxy final : public IMarshal, public IClientSecurity {
+ public:
+  template <typename Iface>
+  static RefPtr<Iface> Wrap(NotNull<Iface*> aIn) {
+    static_assert(detail::VTableSizer<Iface>::Size >= 3, "VTable too small");
+
+#if defined(MOZ_SANDBOX)
+    if (mozilla::GetEffectiveContentSandboxLevel() < 3) {
+      // The sandbox isn't strong enough to be a problem; no wrapping required
+      return aIn.get();
+    }
+
+    typename detail::EnvironmentSelector<Iface>::Type env;
+
+    RefPtr<PassthruProxy> passthru(new PassthruProxy(
+        &env, __uuidof(Iface), detail::VTableSizer<Iface>::Size, aIn));
+
+    RefPtr<Iface> result;
+    if (FAILED(passthru->QueryProxyInterface(getter_AddRefs(result)))) {
+      return nullptr;
+    }
+
+    return result;
+#else
+    // No wrapping required
+    return aIn.get();
+#endif  // defined(MOZ_SANDBOX)
+  }
+
+  static HRESULT Register();
+
+  PassthruProxy();
+
+  // IUnknown
+  STDMETHODIMP QueryInterface(REFIID riid, void** ppv) override;
+  STDMETHODIMP_(ULONG) AddRef() override;
+  STDMETHODIMP_(ULONG) Release() override;
+
+  // IMarshal
+  STDMETHODIMP GetUnmarshalClass(REFIID riid, void* pv, DWORD dwDestContext,
+                                 void* pvDestContext, DWORD mshlflags,
+                                 CLSID* pCid) override;
+  STDMETHODIMP GetMarshalSizeMax(REFIID riid, void* pv, DWORD dwDestContext,
+                                 void* pvDestContext, DWORD mshlflags,
+                                 DWORD* pSize) override;
+  STDMETHODIMP MarshalInterface(IStream* pStm, REFIID riid, void* pv,
+                                DWORD dwDestContext, void* pvDestContext,
+                                DWORD mshlflags) override;
+  STDMETHODIMP UnmarshalInterface(IStream* pStm, REFIID riid,
+                                  void** ppv) override;
+  STDMETHODIMP ReleaseMarshalData(IStream* pStm) override;
+  STDMETHODIMP DisconnectObject(DWORD dwReserved) override;
+
+  // IClientSecurity - we don't actually implement this interface, but its
+  // presence signals to mscom::IsProxy() that we are a proxy.
+  STDMETHODIMP QueryBlanket(IUnknown* aProxy, DWORD* aAuthnSvc,
+                            DWORD* aAuthzSvc, OLECHAR** aSrvPrincName,
+                            DWORD* aAuthnLevel, DWORD* aImpLevel,
+                            void** aAuthInfo, DWORD* aCapabilities) override {
+    return E_NOTIMPL;
+  }
+
+  STDMETHODIMP SetBlanket(IUnknown* aProxy, DWORD aAuthnSvc, DWORD aAuthzSvc,
+                          OLECHAR* aSrvPrincName, DWORD aAuthnLevel,
+                          DWORD aImpLevel, void* aAuthInfo,
+                          DWORD aCapabilities) override {
+    return E_NOTIMPL;
+  }
+
+  STDMETHODIMP CopyProxy(IUnknown* aProxy, IUnknown** aOutCopy) override {
+    return E_NOTIMPL;
+  }
+
+ private:
+  PassthruProxy(ProxyStream::Environment* aEnv, REFIID aIidToWrap,
+                uint32_t aVTableSize, NotNull<IUnknown*> aObjToWrap);
+  ~PassthruProxy();
+
+  bool IsInitialMarshal() const { return !mStream; }
+  HRESULT QueryProxyInterface(void** aOutInterface);
+
+  Atomic<ULONG> mRefCnt;
+  IID mWrappedIid;
+  PreservedStreamPtr mPreservedStream;
+  RefPtr<IStream> mStream;
+  uint32_t mVTableSize;
+  IUnknown* mVTable;
+  bool mForgetPreservedStream;
+};
+
+}  // namespace mscom
+}  // namespace mozilla
+
+#endif  // mozilla_mscom_PassthruProxy_h