Index: sandbox/linux/services/proc_util.h |
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 |
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+// 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/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. |
+ // If /proc is available, |proc_fd| can be passed as -1. |
+ // If |proc_fd| is -1 and /proc is not available, this function will return |
+ // false. |
+ static bool HasOpenDirectory(int proc_fd); |
+ |
+ private: |
+ DISALLOW_IMPLICIT_CONSTRUCTORS(ProcUtil); |
+}; |
+ |
+} // namespace sandbox |
+ |
+#endif // SANDBOX_LINUX_SERVICES_PROC_UTIL_H_ |