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diff --git a/brillo/namespaces/mount_namespace.h b/brillo/namespaces/mount_namespace.h
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+// Copyright 2020 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef LIBBRILLO_BRILLO_NAMESPACES_MOUNT_NAMESPACE_H_
+#define LIBBRILLO_BRILLO_NAMESPACES_MOUNT_NAMESPACE_H_
+
+#include "brillo/namespaces/platform.h"
+
+#include <base/files/file_path.h>
+#include <base/macros.h>
+#include <brillo/brillo_export.h>
+
+namespace brillo {
+
+class BRILLO_EXPORT MountNamespaceInterface {
+  // An interface declaring the basic functionality of a mount namespace bound
+  // to a specific path. This basic functionality consists of reporting the
+  // namespace path.
+ public:
+  virtual ~MountNamespaceInterface() = default;
+
+  virtual const base::FilePath& path() const = 0;
+};
+
+class BRILLO_EXPORT UnownedMountNamespace : public MountNamespaceInterface {
+  // A class to store and retrieve the path of a persistent namespace. This
+  // class doesn't create nor destroy the namespace.
+ public:
+  explicit UnownedMountNamespace(const base::FilePath& ns_path)
+      : ns_path_(ns_path) {}
+
+  ~UnownedMountNamespace() override;
+
+  const base::FilePath& path() const override { return ns_path_; }
+
+ private:
+  base::FilePath ns_path_;
+
+  DISALLOW_COPY_AND_ASSIGN(UnownedMountNamespace);
+};
+
+class BRILLO_EXPORT MountNamespace : public MountNamespaceInterface {
+  // A class to create a persistent mount namespace bound to a specific path.
+  // A new mount namespace is unshared from the mount namespace of the calling
+  // process when Create() is called; the namespace of the calling process
+  // remains unchanged. Recurring creation on a path is not allowed.
+  //
+  // Given that we cannot ensure that creation always succeeds this class is not
+  // fully RAII, but once the namespace is created (with Create()), it will be
+  // destroyed when the object goes out of scope.
+ public:
+  MountNamespace(const base::FilePath& ns_path, Platform* platform);
+  ~MountNamespace() override;
+
+  bool Create();
+  bool Destroy();
+  const base::FilePath& path() const override { return ns_path_; }
+
+ private:
+  base::FilePath ns_path_;
+  Platform* platform_;
+  bool exists_;
+
+  DISALLOW_COPY_AND_ASSIGN(MountNamespace);
+};
+
+}  // namespace brillo
+
+#endif  // LIBBRILLO_BRILLO_NAMESPACES_MOUNT_NAMESPACE_H_