OSCrypt supports encryption with KWallet

components/os_crypt/key_storage_kwallet.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_kwallet.h"
+
+#include <utility>
+
+#include "base/base64.h"
+#include "base/rand_util.h"
+#include "components/os_crypt/kwallet_dbus.h"
+#include "dbus/bus.h"
+
+KeyStorageKWallet::KeyStorageKWallet(base::nix::DesktopEnvironment desktop_env,
+                                     std::string app_name)
+    : desktop_env_(desktop_env), handle_(-1), app_name_(std::move(app_name)) {}
+
+KeyStorageKWallet::~KeyStorageKWallet() {
+  // The handle is shared between programs that are using the same wallet.
+  // Closing the wallet is a nop in the typical case.
+  bool success = true;
+  ignore_result(kwallet_dbus_->Close(handle_, false, app_name_, &success));
+  kwallet_dbus_->GetSessionBus()->ShutdownAndBlock();
+}
+
+bool KeyStorageKWallet::Init() {
+  // Initialize using the production KWalletDBus.
+  return InitWithKWalletDBus(nullptr);
+}
+
+bool KeyStorageKWallet::InitWithKWalletDBus(
+    std::unique_ptr<KWalletDBus> optional_kwallet_dbus_ptr) {
+  if (optional_kwallet_dbus_ptr) {
+    kwallet_dbus_ = std::move(optional_kwallet_dbus_ptr);
+  } else {
+    // Initializing with production KWalletDBus
+    kwallet_dbus_.reset(new KWalletDBus(desktop_env_));
+    dbus::Bus::Options options;
+    options.bus_type = dbus::Bus::SESSION;
+    options.connection_type = dbus::Bus::PRIVATE;
+    kwallet_dbus_->SetSessionBus(new dbus::Bus(options));
+  }
+
+  InitResult result = InitWallet();
+  // If KWallet might not have started, attempt to start it and retry.
+  if (result == InitResult::TEMPORARY_FAIL && kwallet_dbus_->StartKWalletd())
+    result = InitWallet();
+
+  return result == InitResult::SUCCESS;
+}
+
+KeyStorageKWallet::InitResult KeyStorageKWallet::InitWallet() {
+  // Check that KWallet is enabled.
+  bool enabled = false;
+  KWalletDBus::Error error = kwallet_dbus_->IsEnabled(&enabled);
+  switch (error) {
+    case KWalletDBus::Error::CANNOT_CONTACT:
+      return InitResult::TEMPORARY_FAIL;
+    case KWalletDBus::Error::CANNOT_READ:
+      return InitResult::PERMANENT_FAIL;
+    case KWalletDBus::Error::SUCCESS:
+      break;
+  }
+  if (!enabled)
+    return InitResult::PERMANENT_FAIL;
+
+  // Get the wallet name.
+  error = kwallet_dbus_->NetworkWallet(&wallet_name_);
+  switch (error) {
+    case KWalletDBus::Error::CANNOT_CONTACT:
+      return InitResult::TEMPORARY_FAIL;
+    case KWalletDBus::Error::CANNOT_READ:
+      return InitResult::PERMANENT_FAIL;
+    case KWalletDBus::Error::SUCCESS:
+      return InitResult::SUCCESS;
+  }
+
+  NOTREACHED();
+  return InitResult::PERMANENT_FAIL;
+}
+
+std::string KeyStorageKWallet::GetKey() {
+  // Get handle
+  KWalletDBus::Error error =
+      kwallet_dbus_->Open(wallet_name_, app_name_, &handle_);
+  if (error || handle_ == -1)
+    return std::string();
+
+  // Create folder
+  if (!InitFolder())
+    return std::string();
+
+  // Read password
+  std::string password;
+  error =
+      kwallet_dbus_->ReadPassword(handle_, KeyStorageLinux::kFolderName,
+                                  KeyStorageLinux::kKey, app_name_, &password);
+  if (error)
+    return std::string();
+
+  // If there is no entry, generate and write a new password.
+  if (password.empty()) {
+    base::Base64Encode(base::RandBytesAsString(16), &password);
+    bool success;
+    error = kwallet_dbus_->WritePassword(handle_, KeyStorageLinux::kFolderName,
+                                         KeyStorageLinux::kKey, password,
+                                         app_name_, &success);
+    if (error || !success)
+      return std::string();
+  }
+
+  return password;
+}
+
+bool KeyStorageKWallet::InitFolder() {
+  bool has_folder = false;
+  KWalletDBus::Error error = kwallet_dbus_->HasFolder(
+      handle_, KeyStorageLinux::kFolderName, app_name_, &has_folder);
+  if (error)
+    return false;
+
+  if (!has_folder) {
+    bool success = false;
+    error = kwallet_dbus_->CreateFolder(handle_, KeyStorageLinux::kFolderName,
+                                        app_name_, &success);
+    if (error || !success)
+      return false;
+  }
+
+  return true;
+}