// 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 <string>

#include "base/logging.h"
#include "base/macros.h"
#include "components/os_crypt/key_storage_libsecret.h"
#include "components/os_crypt/libsecret_util_linux.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace {

// Mock functions expect MockSecretValue, where SecretValue appears, and cast it
// to the mock type. We can reduce SecretValue to an std::string, because we
// don't use anything else from it.
using MockSecretValue = std::string;
// Likewise, we only need a SecretValue from SecretItem.
using MockSecretItem = MockSecretValue;

const SecretSchema kKeystoreSchemaV1 = {
    "chrome_libsecret_os_crypt_password",
    SECRET_SCHEMA_NONE,
    {
        {nullptr, SECRET_SCHEMA_ATTRIBUTE_STRING},
    }};

const SecretSchema kKeystoreSchemaV2 = {
    "chrome_libsecret_os_crypt_password_v2",
    SECRET_SCHEMA_DONT_MATCH_NAME,
    {
        {"application", SECRET_SCHEMA_ATTRIBUTE_STRING},
        {nullptr, SECRET_SCHEMA_ATTRIBUTE_STRING},
    }};

// Replaces some of LibsecretLoader's methods with mocked ones.
class MockLibsecretLoader : public LibsecretLoader {
 public:
  // Sets up the minimum mock implementation necessary for OSCrypt to work
  // with Libsecret. Also resets the state to mock a clean database.
  static bool ResetForOSCrypt();

  // Sets OSCrypt's password in the libsecret mock to a specific value
  static void SetOSCryptPassword(const char*);

  // Releases memory and restores LibsecretLoader to an uninitialized state.
  static void TearDown();

  // Set whether there is an old password that needs to be migrated from the
  // deprecated schema. Null means no such password. See crbug.com/639298
  static void SetDeprecatedOSCryptPassword(const char* value);

 private:
  // These methods are used to redirect calls through LibsecretLoader
  static const gchar* mock_secret_value_get_text(SecretValue* value);

  static gboolean mock_secret_password_store_sync(const SecretSchema* schema,
                                                  const gchar* collection,
                                                  const gchar* label,
                                                  const gchar* password,
                                                  GCancellable* cancellable,
                                                  GError** error,
                                                  ...);

  static void mock_secret_value_unref(gpointer value);

  static GList* mock_secret_service_search_sync(SecretService* service,
                                                const SecretSchema* schema,
                                                GHashTable* attributes,
                                                SecretSearchFlags flags,
                                                GCancellable* cancellable,
                                                GError** error);

  static gboolean mock_secret_password_clear_sync(const SecretSchema* schema,
                                                  GCancellable* cancellable,
                                                  GError** error,
                                                  ...);

  static SecretValue* mock_secret_item_get_secret(SecretItem* item);

  // MockLibsecretLoader owns these objects.
  static MockSecretValue* stored_password_mock_ptr_;
  static MockSecretValue* deprecated_password_mock_ptr_;
};

MockSecretValue* MockLibsecretLoader::stored_password_mock_ptr_ = nullptr;
MockSecretValue* MockLibsecretLoader::deprecated_password_mock_ptr_ = nullptr;

const gchar* MockLibsecretLoader::mock_secret_value_get_text(
    SecretValue* value) {
  MockSecretValue* mock_value = reinterpret_cast<MockSecretValue*>(value);
  return mock_value->c_str();
}

// static
gboolean MockLibsecretLoader::mock_secret_password_store_sync(
    const SecretSchema* schema,
    const gchar* collection,
    const gchar* label,
    const gchar* password,
    GCancellable* cancellable,
    GError** error,
    ...) {
  // TODO(crbug.com/660005) We don't read the dummy we store to unlock keyring.
  if (strcmp("_chrome_dummy_schema_for_unlocking", schema->name) == 0)
    return true;

  EXPECT_STREQ(kKeystoreSchemaV2.name, schema->name);
  delete stored_password_mock_ptr_;
  stored_password_mock_ptr_ = new MockSecretValue(password);
  return true;
}

// static
void MockLibsecretLoader::mock_secret_value_unref(gpointer value) {}

// static
GList* MockLibsecretLoader::mock_secret_service_search_sync(
    SecretService* service,
    const SecretSchema* schema,
    GHashTable* attributes,
    SecretSearchFlags flags,
    GCancellable* cancellable,
    GError** error) {
  bool is_known_schema = strcmp(schema->name, kKeystoreSchemaV2.name) == 0 ||
                         strcmp(schema->name, kKeystoreSchemaV1.name) == 0;
  EXPECT_TRUE(is_known_schema);

  EXPECT_TRUE(flags & SECRET_SEARCH_UNLOCK);
  EXPECT_TRUE(flags & SECRET_SEARCH_LOAD_SECRETS);

  MockSecretItem* item = nullptr;
  if (strcmp(schema->name, kKeystoreSchemaV2.name) == 0)
    item = stored_password_mock_ptr_;
  else if (strcmp(schema->name, kKeystoreSchemaV1.name) == 0)
    item = deprecated_password_mock_ptr_;

  GList* result = nullptr;
  result = g_list_append(result, item);
  g_clear_error(error);
  return result;
}

// static
gboolean MockLibsecretLoader::mock_secret_password_clear_sync(
    const SecretSchema* schema,
    GCancellable* cancellable,
    GError** error,
    ...) {
  // We would only delete entries in the deprecated schema.
  EXPECT_STREQ(kKeystoreSchemaV1.name, schema->name);
  delete deprecated_password_mock_ptr_;
  deprecated_password_mock_ptr_ = nullptr;
  return true;
}

// static
SecretValue* MockLibsecretLoader::mock_secret_item_get_secret(
    SecretItem* item) {
  static_assert(std::is_same<MockSecretValue, MockSecretItem>::value,
                "mock_secret_item_get_secret() assumes that the only thing we "
                "need from MockSercetItem is the MockSecretValue");
  return reinterpret_cast<SecretValue*>(item);
}

// static
bool MockLibsecretLoader::ResetForOSCrypt() {
  // Methods used by KeyStorageLibsecret
  secret_password_store_sync =
      &MockLibsecretLoader::mock_secret_password_store_sync;
  secret_value_get_text = &MockLibsecretLoader::mock_secret_value_get_text;
  secret_value_unref = &MockLibsecretLoader::mock_secret_value_unref;
  secret_service_search_sync =
      &MockLibsecretLoader::mock_secret_service_search_sync;
  secret_item_get_secret = &MockLibsecretLoader::mock_secret_item_get_secret;
  // Used by Migrate()
  secret_password_clear_sync =
      &MockLibsecretLoader::mock_secret_password_clear_sync;

  delete stored_password_mock_ptr_;
  stored_password_mock_ptr_ = nullptr;
  libsecret_loaded_ = true;

  return true;
}

// static
void MockLibsecretLoader::SetOSCryptPassword(const char* value) {
  delete stored_password_mock_ptr_;
  stored_password_mock_ptr_ = new MockSecretValue(value);
}

// static
void MockLibsecretLoader::SetDeprecatedOSCryptPassword(const char* value) {
  delete deprecated_password_mock_ptr_;
  deprecated_password_mock_ptr_ = new MockSecretValue(value);
}

// static
void MockLibsecretLoader::TearDown() {
  delete stored_password_mock_ptr_;
  stored_password_mock_ptr_ = nullptr;
  libsecret_loaded_ =
      false;  // Function pointers will be restored when loading.
}

class LibsecretTest : public testing::Test {
 public:
  LibsecretTest() = default;
  ~LibsecretTest() override = default;

  void SetUp() override { MockLibsecretLoader::ResetForOSCrypt(); }

  void TearDown() override { MockLibsecretLoader::TearDown(); }

 private:
  DISALLOW_COPY_AND_ASSIGN(LibsecretTest);
};

TEST_F(LibsecretTest, LibsecretRepeats) {
  KeyStorageLibsecret libsecret;
  MockLibsecretLoader::ResetForOSCrypt();
  std::string password = libsecret.GetKey();
  EXPECT_FALSE(password.empty());
  std::string password_repeat = libsecret.GetKey();
  EXPECT_EQ(password, password_repeat);
}

TEST_F(LibsecretTest, LibsecretCreatesRandomised) {
  KeyStorageLibsecret libsecret;
  MockLibsecretLoader::ResetForOSCrypt();
  std::string password = libsecret.GetKey();
  MockLibsecretLoader::ResetForOSCrypt();
  std::string password_new = libsecret.GetKey();
  EXPECT_NE(password, password_new);
}

TEST_F(LibsecretTest, LibsecretMigratesFromSchemaV1ToV2) {
  KeyStorageLibsecret libsecret;
  MockLibsecretLoader::ResetForOSCrypt();
  MockLibsecretLoader::SetDeprecatedOSCryptPassword("swallow");
  std::string password = libsecret.GetKey();
  EXPECT_EQ("swallow", password);
}

}  // namespace