| // 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_ |