Separate cert loading code from CertLibrary and move to src/chromeos.

The intention of this CL is to move certificate loading code without chrome/i18n dependencies into src/chromeos. This is so that networking code that needs access to certificates can also be moved to src/chromeos.

This also extracts CertLibrary from CrosLibrary.

BUG=133752
R=gspencer@chromium.org, pneubeck@chromium.org

Review URL: https://codereview.chromium.org/14522013

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@198511 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 399 insertions, 0 deletions

diff --git a/chromeos/network/cert_loader.cc b/chromeos/network/cert_loader.cc
new file mode 100644
index 0000000..1198acc
--- /dev/null
+++ b/chromeos/network/cert_loader.cc
@@ -0,0 +1,260 @@
+// Copyright (c) 2013 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 "chromeos/network/cert_loader.h"
+
+#include <algorithm>
+
+#include "base/chromeos/chromeos_version.h"
+#include "base/observer_list.h"
+#include "base/task_runner_util.h"
+#include "base/threading/worker_pool.h"
+#include "chromeos/dbus/cryptohome_client.h"
+#include "chromeos/dbus/dbus_thread_manager.h"
+#include "crypto/encryptor.h"
+#include "crypto/nss_util.h"
+#include "crypto/sha2.h"
+#include "crypto/symmetric_key.h"
+#include "net/cert/nss_cert_database.h"
+
+namespace chromeos {
+
+namespace {
+
+// Delay between certificate requests while waiting for TPM/PKCS#11 init.
+const int kRequestDelayMs = 500;
+
+net::CertificateList* LoadNSSCertificates() {
+  net::CertificateList* cert_list(new net::CertificateList());
+  net::NSSCertDatabase::GetInstance()->ListCerts(cert_list);
+  return cert_list;
+}
+
+}  // namespace
+
+static CertLoader* g_cert_loader = NULL;
+
+// static
+void CertLoader::Initialize() {
+  CHECK(!g_cert_loader);
+  g_cert_loader = new CertLoader();
+}
+
+// static
+void CertLoader::Shutdown() {
+  CHECK(g_cert_loader);
+  delete g_cert_loader;
+  g_cert_loader = NULL;
+}
+
+// static
+CertLoader* CertLoader::Get() {
+  CHECK(g_cert_loader) << "CertLoader::Get() called before Initialize()";
+  return g_cert_loader;
+}
+
+// static
+bool CertLoader::IsInitialized() {
+  return g_cert_loader;
+}
+
+CertLoader::CertLoader()
+    : tpm_token_ready_(false),
+      certificates_requested_(false),
+      certificates_loaded_(false),
+      key_store_loaded_(false),
+      weak_ptr_factory_(this) {
+  net::CertDatabase::GetInstance()->AddObserver(this);
+  LoginState::Get()->AddObserver(this);
+  if (LoginState::Get()->IsUserLoggedIn())
+    RequestCertificates();
+}
+
+CertLoader::~CertLoader() {
+  request_task_.Reset();
+  net::CertDatabase::GetInstance()->RemoveObserver(this);
+  LoginState::Get()->RemoveObserver(this);
+}
+
+void CertLoader::AddObserver(CertLoader::Observer* observer) {
+  observers_.AddObserver(observer);
+}
+
+void CertLoader::RemoveObserver(CertLoader::Observer* observer) {
+  observers_.RemoveObserver(observer);
+}
+
+bool CertLoader::CertificatesLoading() const {
+  return certificates_requested_ && !certificates_loaded_;
+}
+
+bool CertLoader::IsHardwareBacked() const {
+  return !tpm_token_name_.empty();
+}
+
+void CertLoader::RequestCertificates() {
+  CHECK(thread_checker_.CalledOnValidThread());
+  VLOG(1) << "RequestCertificates: " << LoginState::Get()->IsUserLoggedIn();
+  if (!LoginState::Get()->IsUserLoggedIn())
+    return;  // Certificates will be requested on login.
+
+  if (!key_store_loaded_) {
+    // Ensure we've opened the real user's key/certificate database.
+    crypto::OpenPersistentNSSDB();
+
+    if (base::chromeos::IsRunningOnChromeOS())
+      crypto::EnableTPMTokenForNSS();
+
+    key_store_loaded_ = true;
+  }
+
+  certificates_requested_ = true;
+
+  VLOG(1) << "Requesting Certificates.";
+  DBusThreadManager::Get()->GetCryptohomeClient()->TpmIsEnabled(
+      base::Bind(&CertLoader::OnTpmIsEnabled,
+                 weak_ptr_factory_.GetWeakPtr()));
+
+  return;
+}
+
+void CertLoader::OnTpmIsEnabled(DBusMethodCallStatus call_status,
+                                bool tpm_is_enabled) {
+  VLOG(1) << "OnTpmIsEnabled: " << tpm_is_enabled;
+  if (call_status != DBUS_METHOD_CALL_SUCCESS || !tpm_is_enabled) {
+    // TPM is not enabled, so proceed with empty tpm token name.
+    VLOG(1) << "TPM not available.";
+    StartLoadCertificates();
+  } else if (tpm_token_ready_) {
+    // Once the TPM token is ready, initialize it.
+    InitializeTPMToken();
+  } else {
+    DBusThreadManager::Get()->GetCryptohomeClient()->Pkcs11IsTpmTokenReady(
+        base::Bind(&CertLoader::OnPkcs11IsTpmTokenReady,
+                   weak_ptr_factory_.GetWeakPtr()));
+  }
+}
+
+void CertLoader::OnPkcs11IsTpmTokenReady(DBusMethodCallStatus call_status,
+                                         bool is_tpm_token_ready) {
+  VLOG(1) << "OnPkcs11IsTpmTokenReady: " << is_tpm_token_ready;
+  if (call_status != DBUS_METHOD_CALL_SUCCESS || !is_tpm_token_ready) {
+    MaybeRetryRequestCertificates();
+    return;
+  }
+
+  // Retrieve token_name_ and user_pin_ here since they will never change
+  // and CryptohomeClient calls are not thread safe.
+  DBusThreadManager::Get()->GetCryptohomeClient()->Pkcs11GetTpmTokenInfo(
+      base::Bind(&CertLoader::OnPkcs11GetTpmTokenInfo,
+                 weak_ptr_factory_.GetWeakPtr()));
+}
+
+void CertLoader::OnPkcs11GetTpmTokenInfo(DBusMethodCallStatus call_status,
+                                         const std::string& token_name,
+                                         const std::string& user_pin) {
+  VLOG(1) << "OnPkcs11GetTpmTokenInfo: " << token_name;
+  if (call_status != DBUS_METHOD_CALL_SUCCESS) {
+    MaybeRetryRequestCertificates();
+    return;
+  }
+  tpm_token_name_ = token_name;
+  // TODO(stevenjb): The network code expects a slot ID, not a label. See
+  // crbug.com/201101. For now, use a hard coded, well known slot instead.
+  const char kHardcodedTpmSlot[] = "0";
+  tpm_token_slot_ = kHardcodedTpmSlot;
+  tpm_user_pin_ = user_pin;
+  tpm_token_ready_ = true;
+
+  InitializeTPMToken();
+}
+
+void CertLoader::InitializeTPMToken() {
+  VLOG(1) << "InitializeTPMToken";
+  if (!crypto::InitializeTPMToken(tpm_token_name_, tpm_user_pin_)) {
+    MaybeRetryRequestCertificates();
+    return;
+  }
+  StartLoadCertificates();
+}
+
+void CertLoader::StartLoadCertificates() {
+  VLOG(1) << "Start Load Certificates";
+  base::PostTaskAndReplyWithResult(
+      base::WorkerPool::GetTaskRunner(true /* task_is_slow */),
+      FROM_HERE,
+      base::Bind(LoadNSSCertificates),
+      base::Bind(&CertLoader::UpdateCertificates,
+                 weak_ptr_factory_.GetWeakPtr()));
+}
+
+void CertLoader::UpdateCertificates(net::CertificateList* cert_list) {
+  CHECK(thread_checker_.CalledOnValidThread());
+  DCHECK(cert_list);
+  VLOG(1) << "Update Certificates: " << cert_list->size();
+
+  // Clear any existing certificates.
+  cert_list_.swap(*cert_list);
+
+  // cert_list is constructed in LoadCertificates.
+  delete cert_list;
+
+  // Set loaded state and notify observers.
+  if (!certificates_loaded_) {
+    certificates_loaded_ = true;
+    NotifyCertificatesLoaded(true);
+  } else {
+    NotifyCertificatesLoaded(false);
+  }
+}
+
+void CertLoader::MaybeRetryRequestCertificates() {
+  if (!request_task_.is_null())
+    return;
+
+  // Cryptohome does not notify us when the token is ready, so call
+  // this again after a delay.
+  request_task_ = base::Bind(&CertLoader::RequestCertificatesTask,
+                             weak_ptr_factory_.GetWeakPtr());
+  MessageLoop::current()->PostDelayedTask(
+      FROM_HERE,
+      request_task_,
+      base::TimeDelta::FromMilliseconds(kRequestDelayMs));
+}
+
+void CertLoader::RequestCertificatesTask() {
+  // Reset the task to the initial state so is_null() returns true.
+  request_task_.Reset();
+  RequestCertificates();
+}
+
+void CertLoader::NotifyCertificatesLoaded(bool initial_load) {
+  FOR_EACH_OBSERVER(Observer, observers_,
+                    OnCertificatesLoaded(cert_list_, initial_load));
+}
+
+void CertLoader::OnCertTrustChanged(const net::X509Certificate* cert) {
+}
+
+void CertLoader::OnCertAdded(const net::X509Certificate* cert) {
+  // Only load certificates if we have completed an initial request.
+  if (!certificates_loaded_)
+    return;
+  StartLoadCertificates();
+}
+
+void CertLoader::OnCertRemoved(const net::X509Certificate* cert) {
+  // Only load certificates if we have completed an initial request.
+  if (!certificates_loaded_)
+    return;
+  StartLoadCertificates();
+}
+
+void CertLoader::LoggedInStateChanged(LoginState::LoggedInState state) {
+  VLOG(1) << "LoggedInStateChanged: " << state;
+  if (LoginState::Get()->IsUserLoggedIn() && !certificates_requested_)
+    RequestCertificates();
+}
+
+}  // namespace chromeos
diff --git a/chromeos/network/cert_loader.h b/chromeos/network/cert_loader.h
new file mode 100644
index 0000000..f3b69ae
--- /dev/null
+++ b/chromeos/network/cert_loader.h
@@ -0,0 +1,139 @@
+// Copyright (c) 2013 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.
+
+#ifndef CHROMEOS_NETWORK_CERT_LOADER_H_
+#define CHROMEOS_NETWORK_CERT_LOADER_H_
+
+#include <string>
+
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+#include "base/memory/weak_ptr.h"
+#include "base/observer_list_threadsafe.h"
+#include "base/threading/thread_checker.h"
+#include "chromeos/chromeos_export.h"
+#include "chromeos/dbus/dbus_method_call_status.h"
+#include "chromeos/login/login_state.h"
+#include "net/cert/cert_database.h"
+#include "net/cert/x509_certificate.h"
+
+namespace crypto {
+class SymmetricKey;
+}
+
+namespace chromeos {
+
+// This class is responsible for initializing the TPM token and loading
+// certificates once the TPM is initialized. It is expected to be constructed
+// on the UI thread and public methods should all be called from the UI thread.
+// When certificates have been loaded (after login completes), or the cert
+// database changes, observers are called with OnCertificatesLoaded().
+class CHROMEOS_EXPORT CertLoader : public net::CertDatabase::Observer,
+                                   public LoginState::Observer {
+ public:
+  class Observer {
+   public:
+    virtual ~Observer() {}
+
+    // Called when the certificates, passed for convenience as |cert_list|,
+    // have completed loading. |initial_load| is true the first time this
+    // is called.
+    virtual void OnCertificatesLoaded(const net::CertificateList& cert_list,
+                                      bool initial_load) = 0;
+
+   protected:
+    Observer() {}
+
+   private:
+    DISALLOW_COPY_AND_ASSIGN(Observer);
+  };
+
+  // Manage the global instance.
+  static void Initialize();
+  static void Shutdown();
+  static CertLoader* Get();
+  static bool IsInitialized();
+
+  void AddObserver(CertLoader::Observer* observer);
+  void RemoveObserver(CertLoader::Observer* observer);
+
+  // Returns true when the certificate list has been requested but not loaded.
+  bool CertificatesLoading() const;
+
+  // Returns true if the TPM is available for hardware-backed certificates.
+  bool IsHardwareBacked() const;
+
+  bool certificates_loaded() const { return certificates_loaded_; }
+
+  // TPM info is only valid once the TPM is available (IsHardwareBacked is
+  // true). Otherwise empty strings will be returned.
+  const std::string& tpm_token_name() const { return tpm_token_name_; }
+  const std::string& tpm_token_slot() const { return tpm_token_slot_; }
+  const std::string& tpm_user_pin() const { return tpm_user_pin_; }
+
+  // This will be empty until certificates_loaded() is true.
+  const net::CertificateList& cert_list() const { return cert_list_; }
+
+ private:
+  CertLoader();
+  virtual ~CertLoader();
+
+  void RequestCertificates();
+
+  void OnTpmIsEnabled(DBusMethodCallStatus call_status,
+                      bool tpm_is_enabled);
+  void OnPkcs11IsTpmTokenReady(DBusMethodCallStatus call_status,
+                               bool is_tpm_token_ready);
+  void OnPkcs11GetTpmTokenInfo(DBusMethodCallStatus call_status,
+                               const std::string& token_name,
+                               const std::string& user_pin);
+  void InitializeTPMToken();
+  void StartLoadCertificates();
+  void UpdateCertificates(net::CertificateList* cert_list);
+  void MaybeRetryRequestCertificates();
+  void RequestCertificatesTask();
+
+  void NotifyCertificatesLoaded(bool initial_load);
+
+  // net::CertDatabase::Observer
+  virtual void OnCertTrustChanged(const net::X509Certificate* cert) OVERRIDE;
+  virtual void OnCertAdded(const net::X509Certificate* cert) OVERRIDE;
+  virtual void OnCertRemoved(const net::X509Certificate* cert) OVERRIDE;
+
+  // LoginState::Observer
+  virtual void LoggedInStateChanged(LoginState::LoggedInState state) OVERRIDE;
+
+  ObserverList<Observer> observers_;
+
+  // Active request task for re-requests while waiting for TPM init.
+  base::Closure request_task_;
+
+  // Local state.
+  bool tpm_token_ready_;
+  bool certificates_requested_;
+  bool certificates_loaded_;
+  // The key store for the current user has been loaded. This flag is needed to
+  // ensure that the key store will not be loaded twice in the policy recovery
+  // "safe-mode".
+  bool key_store_loaded_;
+
+  // Cached TPM token info.
+  std::string tpm_token_name_;
+  std::string tpm_token_slot_;
+  std::string tpm_user_pin_;
+
+  // Cached Certificates.
+  net::CertificateList cert_list_;
+
+  base::ThreadChecker thread_checker_;
+
+  // TODO(stevenjb): Use multiple factories to track callback chains.
+  base::WeakPtrFactory<CertLoader> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(CertLoader);
+};
+
+}  // namespace chromeos
+
+#endif  // CHROMEOS_NETWORK_CERT_LOADER_H_