| // 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. |
| |
| #include "sandbox/linux/services/proc_util.h" |
| |
| #include <dirent.h> |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <string.h> |
| #include <sys/stat.h> |
| #include <sys/types.h> |
| |
| #include <memory> |
| |
| #include "base/logging.h" |
| #include "base/posix/eintr_wrapper.h" |
| #include "base/strings/string_number_conversions.h" |
| |
| namespace sandbox { |
| namespace { |
| |
| struct DIRCloser { |
| void operator()(DIR* d) const { |
| DCHECK(d); |
| PCHECK(0 == closedir(d)); |
| } |
| }; |
| |
| typedef std::unique_ptr<DIR, DIRCloser> ScopedDIR; |
| |
| base::ScopedFD OpenDirectory(const char* path) { |
| DCHECK(path); |
| base::ScopedFD directory_fd( |
| HANDLE_EINTR(open(path, O_RDONLY | O_DIRECTORY | O_CLOEXEC))); |
| PCHECK(directory_fd.is_valid()); |
| return directory_fd; |
| } |
| |
| } // namespace |
| |
| int ProcUtil::CountOpenFds(int proc_fd) { |
| DCHECK_LE(0, proc_fd); |
| int proc_self_fd = HANDLE_EINTR( |
| openat(proc_fd, "self/fd/", O_DIRECTORY | O_RDONLY | O_CLOEXEC)); |
| PCHECK(0 <= proc_self_fd); |
| |
| // Ownership of proc_self_fd is transferred here, it must not be closed |
| // or modified afterwards except via dir. |
| ScopedDIR dir(fdopendir(proc_self_fd)); |
| CHECK(dir); |
| |
| int count = 0; |
| struct dirent* de; |
| while ((de = readdir(dir.get()))) { |
| if (strcmp(de->d_name, ".") == 0 || strcmp(de->d_name, "..") == 0) { |
| continue; |
| } |
| |
| int fd_num; |
| CHECK(base::StringToInt(de->d_name, &fd_num)); |
| if (fd_num == proc_fd || fd_num == proc_self_fd) { |
| continue; |
| } |
| |
| ++count; |
| } |
| return count; |
| } |
| |
| bool ProcUtil::HasOpenDirectory(int proc_fd) { |
| DCHECK_LE(0, proc_fd); |
| int proc_self_fd = |
| openat(proc_fd, "self/fd/", O_DIRECTORY | O_RDONLY | O_CLOEXEC); |
| |
| PCHECK(0 <= proc_self_fd); |
| |
| // Ownership of proc_self_fd is transferred here, it must not be closed |
| // or modified afterwards except via dir. |
| ScopedDIR dir(fdopendir(proc_self_fd)); |
| CHECK(dir); |
| |
| struct dirent* de; |
| while ((de = readdir(dir.get()))) { |
| if (strcmp(de->d_name, ".") == 0 || strcmp(de->d_name, "..") == 0) { |
| continue; |
| } |
| |
| int fd_num; |
| CHECK(base::StringToInt(de->d_name, &fd_num)); |
| if (fd_num == proc_fd || fd_num == proc_self_fd) { |
| continue; |
| } |
| |
| struct stat s; |
| // It's OK to use proc_self_fd here, fstatat won't modify it. |
| CHECK(fstatat(proc_self_fd, de->d_name, &s, 0) == 0); |
| if (S_ISDIR(s.st_mode)) { |
| return true; |
| } |
| } |
| |
| // No open unmanaged directories found. |
| return false; |
| } |
| |
| bool ProcUtil::HasOpenDirectory() { |
| base::ScopedFD proc_fd( |
| HANDLE_EINTR(open("/proc/", O_DIRECTORY | O_RDONLY | O_CLOEXEC))); |
| return HasOpenDirectory(proc_fd.get()); |
| } |
| |
| // static |
| base::ScopedFD ProcUtil::OpenProc() { |
| return OpenDirectory("/proc/"); |
| } |
| |
| } // namespace sandbox |