diff --git a/common/hash_calculator_unittest.cc b/common/hash_calculator_unittest.cc
index e8f73d5..fe7d543 100644
--- a/common/hash_calculator_unittest.cc
+++ b/common/hash_calculator_unittest.cc
@@ -104,7 +104,7 @@
 }
 
 TEST_F(HashCalculatorTest, UpdateFileSimpleTest) {
-  test_utils::ScopedTempFile data_file("data.XXXXXX");
+  ScopedTempFile data_file("data.XXXXXX");
   ASSERT_TRUE(test_utils::WriteFileString(data_file.path(), "hi"));
 
   for (const int length : {-1, 2, 10}) {
@@ -126,7 +126,7 @@
 }
 
 TEST_F(HashCalculatorTest, RawHashOfFileSimpleTest) {
-  test_utils::ScopedTempFile data_file("data.XXXXXX");
+  ScopedTempFile data_file("data.XXXXXX");
   ASSERT_TRUE(test_utils::WriteFileString(data_file.path(), "hi"));
 
   for (const int length : {-1, 2, 10}) {
diff --git a/common/http_fetcher_unittest.cc b/common/http_fetcher_unittest.cc
index 1ead681..99ea99b 100644
--- a/common/http_fetcher_unittest.cc
+++ b/common/http_fetcher_unittest.cc
@@ -369,7 +369,7 @@
   HttpServer* CreateServer() override { return new NullHttpServer; }
 
  private:
-  test_utils::ScopedTempFile temp_file_{"ue_file_fetcher.XXXXXX"};
+  ScopedTempFile temp_file_{"ue_file_fetcher.XXXXXX"};
 };
 
 class MultiRangeHttpFetcherOverFileFetcherTest : public FileFetcherTest {
diff --git a/common/test_utils.h b/common/test_utils.h
index 63ea749..bb5a678 100644
--- a/common/test_utils.h
+++ b/common/test_utils.h
@@ -138,22 +138,6 @@
   DISALLOW_COPY_AND_ASSIGN(ScopedLoopbackDeviceBinder);
 };
 
-class ScopedTempFile {
- public:
-  ScopedTempFile() : ScopedTempFile("update_engine_test_temp_file.XXXXXX") {}
-
-  explicit ScopedTempFile(const std::string& pattern) {
-    EXPECT_TRUE(utils::MakeTempFile(pattern, &path_, nullptr));
-    unlinker_.reset(new ScopedPathUnlinker(path_));
-  }
-
-  const std::string& path() const { return path_; }
-
- private:
-  std::string path_;
-  std::unique_ptr<ScopedPathUnlinker> unlinker_;
-};
-
 class ScopedLoopMounter {
  public:
   explicit ScopedLoopMounter(const std::string& file_path,
diff --git a/common/utils.h b/common/utils.h
index f364bfd..05a92be 100644
--- a/common/utils.h
+++ b/common/utils.h
@@ -370,6 +370,42 @@
   DISALLOW_COPY_AND_ASSIGN(ScopedPathUnlinker);
 };
 
+class ScopedTempFile {
+ public:
+  ScopedTempFile() : ScopedTempFile("update_engine_temp.XXXXXX") {}
+
+  // If |open_fd| is true, a writable file descriptor will be opened for this
+  // file.
+  explicit ScopedTempFile(const std::string& pattern, bool open_fd = false) {
+    CHECK(utils::MakeTempFile(pattern, &path_, open_fd ? &fd_ : nullptr));
+    unlinker_.reset(new ScopedPathUnlinker(path_));
+    if (open_fd) {
+      CHECK_GE(fd_, 0);
+      fd_closer_.reset(new ScopedFdCloser(&fd_));
+    }
+  }
+  virtual ~ScopedTempFile() = default;
+
+  const std::string& path() const { return path_; }
+  int fd() const {
+    CHECK(fd_closer_);
+    return fd_;
+  }
+  void CloseFd() {
+    CHECK(fd_closer_);
+    fd_closer_.reset();
+  }
+
+ private:
+  std::string path_;
+  std::unique_ptr<ScopedPathUnlinker> unlinker_;
+
+  int fd_{-1};
+  std::unique_ptr<ScopedFdCloser> fd_closer_;
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedTempFile);
+};
+
 // A little object to call ActionComplete on the ActionProcessor when
 // it's destructed.
 class ScopedActionCompleter {
diff --git a/common/utils_unittest.cc b/common/utils_unittest.cc
index bc5c3b0..20c6b84 100644
--- a/common/utils_unittest.cc
+++ b/common/utils_unittest.cc
@@ -46,7 +46,7 @@
 }
 
 TEST(UtilsTest, WriteFileReadFile) {
-  test_utils::ScopedTempFile file;
+  ScopedTempFile file;
   EXPECT_TRUE(utils::WriteFile(file.path().c_str(), "hello", 5));
 
   brillo::Blob readback;
@@ -60,7 +60,7 @@
 }
 
 TEST(UtilsTest, ReadFileChunk) {
-  test_utils::ScopedTempFile file;
+  ScopedTempFile file;
   brillo::Blob data;
   const size_t kSize = 1024 * 1024;
   for (size_t i = 0; i < kSize; i++) {
@@ -149,7 +149,7 @@
 namespace {
 void GetFileFormatTester(const string& expected,
                          const vector<uint8_t>& contents) {
-  test_utils::ScopedTempFile file;
+  ScopedTempFile file;
   ASSERT_TRUE(utils::WriteFile(file.path().c_str(),
                                reinterpret_cast<const char*>(contents.data()),
                                contents.size()));
@@ -378,7 +378,7 @@
 }
 
 TEST(UtilsTest, RunAsRootUnmountFilesystemBusyFailureTest) {
-  test_utils::ScopedTempFile tmp_image("img.XXXXXX");
+  ScopedTempFile tmp_image("img.XXXXXX");
 
   EXPECT_TRUE(base::CopyFile(
       test_utils::GetBuildArtifactsPath().Append("gen/disk_ext2_4k.img"),
@@ -418,7 +418,7 @@
   EXPECT_TRUE(mnt_dir.CreateUniqueTempDir());
   EXPECT_FALSE(utils::IsMountpoint(mnt_dir.GetPath().value()));
 
-  test_utils::ScopedTempFile file;
+  ScopedTempFile file;
   EXPECT_FALSE(utils::IsMountpoint(file.path()));
 }
 
@@ -460,7 +460,7 @@
 }
 
 TEST(UtilsTest, GetFilePathTest) {
-  test_utils::ScopedTempFile file;
+  ScopedTempFile file;
   int fd = HANDLE_EINTR(open(file.path().c_str(), O_RDONLY));
   EXPECT_GE(fd, 0);
   EXPECT_EQ(file.path(), utils::GetFilePath(fd));