Implement gnome-keyring for OSCrypt

components/os_crypt/key_storage_keyring.cc

+// Copyright 2016 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 "components/os_crypt/key_storage_keyring.h"
+
+#include <gnome-keyring.h>
+
+#include "base/base64.h"
+#include "base/bind.h"
+#include "base/rand_util.h"
+#include "base/single_thread_task_runner.h"
+#include "base/strings/string_number_conversions.h"
+#include "base/synchronization/waitable_event.h"
+#include "base/threading/thread.h"
+#include "components/os_crypt/keyring_util_linux.h"
+
+namespace {
+
+#if defined(GOOGLE_CHROME_BUILD)
+const char kApplicationName[] = "chrome";
+#else
+const char kApplicationName[] = "chromium";
+#endif
+
+const GnomeKeyringPasswordSchema kSchema = {
+    GNOME_KEYRING_ITEM_GENERIC_SECRET,
+    {{"application", GNOME_KEYRING_ATTRIBUTE_TYPE_STRING}, {nullptr}}};
+
+}  // namespace
+
+KeyStorageKeyring::KeyStorageKeyring(
+    scoped_refptr<base::SingleThreadTaskRunner> main_thread_runner)
+    : main_thread_runner_(main_thread_runner) {
+  thread_checker_.DetachFromThread();
+}
+
+KeyStorageKeyring::~KeyStorageKeyring() {}
+
+bool KeyStorageKeyring::Init() {
+  return GnomeKeyringLoader::LoadGnomeKeyring();
+}
+
+std::string KeyStorageKeyring::GetKey() {
+  std::string password;
+
+  // Ensure GetKeyDelegate() is executed on the main thread.
+  if (main_thread_runner_->BelongsToCurrentThread()) {
+    GetKeyDelegate(&password, nullptr);
+  } else {
+    base::WaitableEvent password_loaded(
+        base::WaitableEvent::ResetPolicy::MANUAL,
+        base::WaitableEvent::InitialState::NOT_SIGNALED);
+    main_thread_runner_->PostTask(
+        FROM_HERE,
+        base::Bind(&KeyStorageKeyring::GetKeyDelegate, base::Unretained(this),
+                   &password, &password_loaded));
+    password_loaded.Wait();
+  }
+
+  return password;
+}
+
+void KeyStorageKeyring::GetKeyDelegate(

[Lei Zhang, 2016/09/01 07:56:31]

Can these be inside an anonymous namespace, instead of (formerly) being static
class methods?

[cfroussios, 2016/09/01 10:58:16]

AddRandomPasswordInKeyring() needs access to protected fields of
KeyStorageLinux. GetKeyDelegate() needs to call AddRandomPasswordInKeyring(),
which is private.

We could make KeyStorageLinux' stuff public, but making stuff public so that the
children can use them smells to me.

+    std::string* password_ptr,
+    base::WaitableEvent* password_loaded_ptr) {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  gchar* password = nullptr;
+  GnomeKeyringResult result =
+      GnomeKeyringLoader::gnome_keyring_find_password_sync_ptr(
+          &kSchema, &password, "application", kApplicationName, nullptr);
+  if (result == GNOME_KEYRING_RESULT_OK) {
+    *password_ptr = password;
+    GnomeKeyringLoader::gnome_keyring_free_password_ptr(password);
+  } else if (result == GNOME_KEYRING_RESULT_NO_MATCH) {
+    *password_ptr = KeyStorageKeyring::AddRandomPasswordInKeyring();
+    VLOG(1) << "OSCrypt generated a new password";
+  } else {
+    password_ptr->clear();
+    VLOG(1) << "OSCrypt failed to use gnome-keyring";
+  }
+
+  if (password_loaded_ptr)

[Lei Zhang, 2016/09/01 07:56:31]

Is this ever false?

[cfroussios, 2016/09/01 10:58:16]

When GetKey() is called on the main thread.

[Lei Zhang, 2016/09/01 17:16:40]

Right, that's what I get for doing late night reviews.

+    password_loaded_ptr->Signal();
+}
+
+std::string KeyStorageKeyring::AddRandomPasswordInKeyring() {
+  DCHECK(thread_checker_.CalledOnValidThread());
+
+  // Generate password
+  std::string password;
+  base::Base64Encode(base::RandBytesAsString(16), &password);
+
+  // Store generated password
+  GnomeKeyringResult result =
+      GnomeKeyringLoader::gnome_keyring_store_password_sync_ptr(
+          &kSchema, nullptr /* default keyring */, KeyStorageLinux::kKey,
+          password.c_str(), "application", kApplicationName, nullptr);
+  if (result != GNOME_KEYRING_RESULT_OK) {
+    VLOG(1) << "Failed to store generated password to gnome-keyring";
+    return std::string();
+  }
+
+  return password;
+}