1 files changed, 42 insertions, 0 deletions
diff --git a/sandbox/linux/services/proc_util.h b/sandbox/linux/services/proc_util.h
new file mode 100644
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+++ b/sandbox/linux/services/proc_util.h
@@ -0,0 +1,42 @@
+// Copyright 2014 The Chromium 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 SANDBOX_LINUX_SERVICES_PROC_UTIL_H_
+#define SANDBOX_LINUX_SERVICES_PROC_UTIL_H_
+
+#include "base/files/scoped_file.h"
+#include "base/macros.h"
+#include "sandbox/sandbox_export.h"
+
+namespace sandbox {
+
+class SANDBOX_EXPORT ProcUtil {
+ public:
+  // Returns the number of file descriptors in the current process's FD
+  // table, excluding |proc_fd|, which should be a file descriptor for
+  // /proc/.
+  static int CountOpenFds(int proc_fd);
+
+  // Checks whether the current process has any directory file descriptor open.
+  // Directory file descriptors are "capabilities" that would let a process use
+  // system calls such as openat() to bypass restrictions such as
+  // DropFileSystemAccess().
+  // Sometimes it's useful to call HasOpenDirectory() after file system access
+  // has been dropped. In this case, |proc_fd| should be a file descriptor to
+  // /proc/. The file descriptor in |proc_fd| will be ignored by
+  // HasOpenDirectory() and remains owned by the caller. It is very important
+  // for the caller to close it.
+  static bool HasOpenDirectory(int proc_fd) WARN_UNUSED_RESULT;
+  static bool HasOpenDirectory() WARN_UNUSED_RESULT;
+
+  // Open /proc/ or crash if not possible.
+  static base::ScopedFD OpenProc();
+
+ private:
+  DISALLOW_IMPLICIT_CONSTRUCTORS(ProcUtil);
+};
+
+}  // namespace sandbox
+
+#endif  // SANDBOX_LINUX_SERVICES_PROC_UTIL_H_