Store/Retrieve CrOS user policy in session_manager.

chrome/browser/policy/cros_user_policy_cache.cc

+// Copyright (c) 2012 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 "chrome/browser/policy/cros_user_policy_cache.h"
+
+#include <string>
+#include <vector>
+
+#include "base/bind.h"
+#include "base/callback.h"
+#include "base/file_path.h"
+#include "base/file_util.h"
+#include "chrome/browser/policy/proto/cloud_policy.pb.h"
+#include "chrome/browser/policy/proto/device_management_backend.pb.h"
+#include "chrome/browser/policy/proto/device_management_local.pb.h"
+#include "chromeos/dbus/session_manager_client.h"
+#include "content/public/browser/browser_thread.h"
+
+using content::BrowserThread;
+
+namespace em = enterprise_management;
+
+namespace policy {
+
+// Decodes a CloudPolicySettings object into a policy map. The implementation is
+// generated code in policy/cloud_policy_generated.cc.
+void DecodePolicy(const em::CloudPolicySettings& policy,
+                  PolicyMap* policies);
+
+// Takes care of sending a new policy blob to session manager and reports back
+// the status through a callback.
+class CrosUserPolicyCache::StorePolicyOperation {
+ public:
+  typedef base::Callback<void(bool)> StatusCallback;
+
+  StorePolicyOperation(
+      const em::PolicyFetchResponse& policy,
+      chromeos::SessionManagerClient* session_manager_client,
+      const StatusCallback& callback);
+
+  // Executes the operation.
+  void Run();
+
+  // Cancels a pending callback.
+  void Cancel();
+
+  const em::PolicyFetchResponse& policy() { return policy_; }
+
+ private:
+  // StorePolicyOperation manages its own lifetime.
+  ~StorePolicyOperation() {}
+
+  // A callback function suitable for passing to session_manager_client.
+  void OnPolicyStored(bool result);
+
+  em::PolicyFetchResponse policy_;
+  chromeos::SessionManagerClient* session_manager_client_;
+  StatusCallback callback_;
+
+  DISALLOW_COPY_AND_ASSIGN(StorePolicyOperation);
+};
+
+CrosUserPolicyCache::StorePolicyOperation::StorePolicyOperation(
+    const em::PolicyFetchResponse& policy,
+    chromeos::SessionManagerClient* session_manager_client,
+    const StatusCallback& callback)
+    : policy_(policy),
+      session_manager_client_(session_manager_client),
+      callback_(callback) {}
+
+void CrosUserPolicyCache::StorePolicyOperation::Run() {
+  std::string serialized;
+  if (!policy_.SerializeToString(&serialized)) {
+    LOG(ERROR) << "Failed to serialize policy protobuf!";
+    callback_.Run(false);
+    delete this;
+  }
+  session_manager_client_->StoreUserPolicy(
+      serialized,
+      base::Bind(&CrosUserPolicyCache::StorePolicyOperation::OnPolicyStored,
+                 base::Unretained(this)));
+}
+
+void CrosUserPolicyCache::StorePolicyOperation::Cancel() {
+  callback_.Reset();
+}
+
+void CrosUserPolicyCache::StorePolicyOperation::OnPolicyStored(bool result) {
+  if (!callback_.is_null())
+    callback_.Run(result);
+  delete this;
+}
+
+class CrosUserPolicyCache::RetrievePolicyOperation {
+ public:
+  typedef base::Callback<void(bool, const em::PolicyFetchResponse&)>
+      ResultCallback;
+
+  RetrievePolicyOperation(
+      chromeos::SessionManagerClient* session_manager_client,
+      const ResultCallback& callback);
+
+  // Executes the operation.
+  void Run();
+
+  // Cancels a pending callback.
+  void Cancel();
+
+ private:
+  // RetrievePolicyOperation manages its own lifetime.
+  ~RetrievePolicyOperation() {}
+
+  // Decodes the policy data and triggers a signature check.
+  void OnPolicyRetrieved(const std::string& policy_blob);
+
+  chromeos::SessionManagerClient* session_manager_client_;
+  ResultCallback callback_;
+
+  DISALLOW_COPY_AND_ASSIGN(RetrievePolicyOperation);
+};
+
+CrosUserPolicyCache::RetrievePolicyOperation::RetrievePolicyOperation(
+    chromeos::SessionManagerClient* session_manager_client,
+    const ResultCallback& callback)
+    : session_manager_client_(session_manager_client),
+      callback_(callback) {}
+
+void CrosUserPolicyCache::RetrievePolicyOperation::Run() {
+  session_manager_client_->RetrieveUserPolicy(
+      base::Bind(
+          &CrosUserPolicyCache::RetrievePolicyOperation::OnPolicyRetrieved,
+          base::Unretained(this)));
+}
+
+void CrosUserPolicyCache::RetrievePolicyOperation::Cancel() {
+  callback_.Reset();
+}
+
+void CrosUserPolicyCache::RetrievePolicyOperation::OnPolicyRetrieved(
+    const std::string& policy_blob) {
+  bool status = true;
+  em::PolicyFetchResponse policy;
+  if (!policy.ParseFromString(policy_blob) ||
+      !policy.has_policy_data() ||
+      !policy.has_policy_data_signature()) {
+    LOG(ERROR) << "Failed to decode policy";
+    status = false;
+  }
+
+  if (!callback_.is_null())
+    callback_.Run(status, policy);
+  delete this;
+}
+
+CrosUserPolicyCache::CrosUserPolicyCache(
+    chromeos::SessionManagerClient* session_manager_client,
+    CloudPolicyDataStore* data_store,
+    bool wait_for_policy_fetch,
+    const FilePath& legacy_token_cache_file,
+    const FilePath& legacy_policy_cache_file)
+    : session_manager_client_(session_manager_client),
+      data_store_(data_store),
+      pending_policy_fetch_(wait_for_policy_fetch),
+      pending_disk_cache_load_(true),
+      store_operation_(NULL),
+      retrieve_operation_(NULL),
+      legacy_cache_dir_(legacy_token_cache_file.DirName()),
+      ALLOW_THIS_IN_INITIALIZER_LIST(
+          legacy_token_cache_delegate_factory_(this)),
+      ALLOW_THIS_IN_INITIALIZER_LIST(
+          legacy_policy_cache_delegate_factory_(this)) {
+  DCHECK_EQ(legacy_token_cache_file.DirName().value(),
+            legacy_policy_cache_file.DirName().value());
+
+  legacy_token_loader_ =
+      new UserPolicyTokenLoader(
+          legacy_token_cache_delegate_factory_.GetWeakPtr(),
+          legacy_token_cache_file);
+  legacy_policy_cache_ =
+      new UserPolicyDiskCache(
+          legacy_policy_cache_delegate_factory_.GetWeakPtr(),
+          legacy_policy_cache_file);
+}
+
+CrosUserPolicyCache::~CrosUserPolicyCache() {
+  CancelStore();
+  CancelRetrieve();
+}
+
+void CrosUserPolicyCache::Load() {
+  retrieve_operation_ =
+      new RetrievePolicyOperation(
+          session_manager_client_,
+          base::Bind(&CrosUserPolicyCache::OnPolicyLoadDone,
+                     base::Unretained(this)));
+  retrieve_operation_->Run();
+}
+
+bool CrosUserPolicyCache::SetPolicy(const em::PolicyFetchResponse& policy) {
+  CancelStore();
+  set_last_policy_refresh_time(base::Time::NowFromSystemTime());
+  pending_policy_fetch_ = true;
+  store_operation_ =
+      new StorePolicyOperation(policy,
+                               session_manager_client_,
+                               base::Bind(&CrosUserPolicyCache::OnPolicyStored,
+                                          base::Unretained(this)));
+  store_operation_->Run();
+  return true;
+}
+
+void CrosUserPolicyCache::SetUnmanaged() {
+  base::Time now(base::Time::NowFromSystemTime());
+  SetUnmanagedInternal(now);
+
+  // Construct a policy blob with unmanaged state.
+  em::PolicyData policy_data;
+  policy_data.set_policy_type(data_store_->policy_type());
+  policy_data.set_timestamp((now - base::Time::UnixEpoch()).InMilliseconds());
+  policy_data.set_state(em::PolicyData::UNMANAGED);
+
+  em::PolicyFetchResponse policy;
+  if (!policy_data.SerializeToString(policy.mutable_policy_data())) {
+    LOG(ERROR) << "Failed to serialize policy_data";
+    return;
+  }
+
+  SetPolicy(policy);
+}
+
+void CrosUserPolicyCache::SetFetchingDone() {
+  // If there is a pending policy store or reload, wait for that to complete
+  // before reporting fetching done.
+  if (store_operation_ || retrieve_operation_)
+    return;
+
+  pending_policy_fetch_ = false;
+  CheckIfDone();
+}
+
+bool CrosUserPolicyCache::DecodePolicyData(const em::PolicyData& policy_data,
+                                           PolicyMap* policies) {
+  em::CloudPolicySettings policy;
+  if (!policy.ParseFromString(policy_data.policy_value())) {
+    LOG(WARNING) << "Failed to parse CloudPolicySettings protobuf.";
+    return false;
+  }
+  DecodePolicy(policy, policies);
+  return true;
+}
+
+void CrosUserPolicyCache::OnTokenLoaded(const std::string& token,
+                                        const std::string& device_id) {
+  if (token.empty())
+    LOG(WARNING) << "Failed to load legacy token cache";
+
+  data_store_->set_device_id(device_id);
+  data_store_->SetDeviceToken(token, true);
+}
+
+void CrosUserPolicyCache::OnDiskCacheLoaded(
+    UserPolicyDiskCache::LoadResult result,
+    const em::CachedCloudPolicyResponse& policy) {
+  if (result == UserPolicyDiskCache::LOAD_RESULT_SUCCESS) {
+    if (policy.unmanaged())
+      SetUnmanagedInternal(base::Time::FromTimeT(policy.timestamp()));
+    else if (policy.has_cloud_policy())
+      InstallLegacyPolicy(policy.cloud_policy());
+  } else {
+    LOG(WARNING) << "Failed to load legacy policy cache: " << result;
+  }
+
+  pending_disk_cache_load_ = false;
+  CheckIfDone();
+}
+
+void CrosUserPolicyCache::OnPolicyStored(bool result) {
+  DCHECK(store_operation_);
+  CancelStore();
+  if (result) {
+    // Policy is stored successfully, reload from session_manager and apply.
+    // This helps us making sure we only use policy that session_manager has
+    // checked and confirmed to be good.
+    CancelRetrieve();
+    retrieve_operation_ =
+        new RetrievePolicyOperation(
+            session_manager_client_,
+            base::Bind(&CrosUserPolicyCache::OnPolicyReloadDone,
+                       base::Unretained(this)));
+    retrieve_operation_->Run();
+
+    // Now that the new policy blob is installed, remove the old cache dir.
+    if (!legacy_cache_dir_.empty()) {
+      BrowserThread::PostTask(BrowserThread::FILE, FROM_HERE,
+                              base::Bind(&RemoveLegacyCacheDir,
+                                         legacy_cache_dir_));
+    }
+  } else {
+    LOG(ERROR) << "Failed to store user policy.";
+    InformNotifier(CloudPolicySubsystem::LOCAL_ERROR,
+                   CloudPolicySubsystem::POLICY_LOCAL_ERROR);
+    pending_policy_fetch_ = false;
+    CheckIfDone();
+  }
+}
+
+void CrosUserPolicyCache::OnPolicyLoadDone(
+    bool result,
+    const em::PolicyFetchResponse& policy) {
+  DCHECK(retrieve_operation_);
+  CancelRetrieve();
+  if (!result) {
+    LOG(WARNING) << "No user policy present, trying legacy caches.";
+    legacy_token_loader_->Load();
+    legacy_policy_cache_->Load();
+    return;
+  }
+
+  // We have new-style policy, no need to clean up.
+  legacy_cache_dir_.clear();
+
+  em::PolicyData policy_data;
+  if (!policy_data.ParseFromString(policy.policy_data())) {
+    LOG(WARNING) << "Failed to parse PolicyData protobuf.";
+    InformNotifier(CloudPolicySubsystem::LOCAL_ERROR,
+                   CloudPolicySubsystem::POLICY_LOCAL_ERROR);
+    data_store_->SetDeviceToken(std::string(), true);
+  } else if (policy_data.request_token().empty() ||
+             policy_data.username().empty() ||
+             policy_data.device_id().empty()) {
+    LOG(WARNING) << "Policy protobuf is missing credentials";
+    InformNotifier(CloudPolicySubsystem::LOCAL_ERROR,
+                   CloudPolicySubsystem::POLICY_LOCAL_ERROR);
+    data_store_->SetDeviceToken(std::string(), true);
+  } else {
+    data_store_->set_device_id(policy_data.device_id());
+    data_store_->SetDeviceToken(policy_data.request_token(), true);
+    if (SetPolicyInternal(policy, NULL, true))
+      set_last_policy_refresh_time(base::Time::NowFromSystemTime());
+  }
+
+  pending_disk_cache_load_ = false;
+  CheckIfDone();
+}
+
+void CrosUserPolicyCache::OnPolicyReloadDone(
+    bool result,
+    const em::PolicyFetchResponse& policy) {
+  DCHECK(retrieve_operation_);
+  CancelRetrieve();
+  if (result) {
+    if (SetPolicyInternal(policy, NULL, false))
+      set_last_policy_refresh_time(base::Time::NowFromSystemTime());
+  } else {
+    InformNotifier(CloudPolicySubsystem::LOCAL_ERROR,
+                   CloudPolicySubsystem::POLICY_LOCAL_ERROR);
+  }
+  pending_policy_fetch_ = false;
+  CheckIfDone();
+}
+
+void CrosUserPolicyCache::CancelStore() {
+  if (store_operation_) {
+    store_operation_->Cancel();
+    store_operation_ = NULL;
+  }
+}
+
+void CrosUserPolicyCache::CancelRetrieve() {
+  if (retrieve_operation_) {
+    retrieve_operation_->Cancel();
+    retrieve_operation_ = NULL;
+  }
+}
+
+void CrosUserPolicyCache::CheckIfDone() {
+  if (!pending_policy_fetch_ && !pending_disk_cache_load_) {
+    if (!IsReady())
+      SetReady();
+    CloudPolicyCacheBase::SetFetchingDone();
+  }
+}
+
+void CrosUserPolicyCache::InstallLegacyPolicy(
+    const em::PolicyFetchResponse& policy) {
+  em::PolicyFetchResponse mutable_policy(policy);
+  mutable_policy.clear_policy_data_signature();
+  mutable_policy.clear_new_public_key();
+  mutable_policy.clear_new_public_key_signature();
+  em::PolicyData policy_data;
+  if (!policy_data.ParseFromString(mutable_policy.policy_data())) {
+    LOG(ERROR) << "Failed to parse policy data.";
+    return;
+  }
+
+  policy_data.clear_public_key_version();
+  if (!policy_data.SerializeToString(mutable_policy.mutable_policy_data())) {
+    LOG(ERROR) << "Failed to serialize policy data.";
+    return;
+  }
+
+  base::Time timestamp;
+  if (SetPolicyInternal(mutable_policy, &timestamp, true))
+    set_last_policy_refresh_time(timestamp);
+}
+
+// static
+void CrosUserPolicyCache::RemoveLegacyCacheDir(const FilePath& dir) {
+  if (!file_util::Delete(dir, true))
+    PLOG(ERROR) << "Failed to remove " << dir.value();
+}
+
+}  // namespace policy