chromeos/cert_loader.h

   1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #ifndef CHROMEOS_CERT_LOADER_H_
   6 #define CHROMEOS_CERT_LOADER_H_
   7
   8 #include <string>
   9 #include <vector>
  10
  11 #include "base/basictypes.h"
  12 #include "base/compiler_specific.h"
  13 #include "base/memory/ref_counted.h"
  14 #include "base/memory/weak_ptr.h"
  15 #include "base/observer_list.h"
  16 #include "base/threading/thread_checker.h"
  17 #include "chromeos/chromeos_export.h"
  18 #include "net/cert/cert_database.h"
  19
  20 namespace net {
  21 class NSSCertDatabase;
  22 class X509Certificate;
  23 typedef std::vector<scoped_refptr<X509Certificate> > CertificateList;
  24 }
  25
  26 namespace chromeos {
  27
  28 // This class is responsible for loading certificates once the TPM is
  29 // initialized. It is expected to be constructed on the UI thread and public
  30 // methods should all be called from the UI thread.
  31 // When certificates have been loaded (after login completes and tpm token is
  32 // initialized), or the cert database changes, observers are called with
  33 // OnCertificatesLoaded().
  34 class CHROMEOS_EXPORT CertLoader : public net::CertDatabase::Observer {
  35  public:
  36   class Observer {
  37    public:
  38     // Called when the certificates, passed for convenience as |cert_list|,
  39     // have completed loading. |initial_load| is true the first time this
  40     // is called.
  41     virtual void OnCertificatesLoaded(const net::CertificateList& cert_list,
  42                                       bool initial_load) = 0;
  43
  44    protected:
  45     virtual ~Observer() {}
  46   };
  47
  48   // Sets the global instance. Must be called before any calls to Get().
  49   static void Initialize();
  50
  51   // Destroys the global instance.
  52   static void Shutdown();
  53
  54   // Gets the global instance. Initialize() must be called first.
  55   static CertLoader* Get();
  56
  57   // Returns true if the global instance has been initialized.
  58   static bool IsInitialized();
  59
  60   static std::string GetPkcs11IdForCert(const net::X509Certificate& cert);
  61
  62   // Starts the CertLoader with the NSS cert database.
  63   // The CertLoader will _not_ take the ownership of the database, but it
  64   // expects it to stay alive at least until the shutdown starts on the main
  65   // thread. This assumes that |StartWithNSSDB| and other methods directly
  66   // using |database_| are not called during shutdown.
  67   void StartWithNSSDB(net::NSSCertDatabase* database);
  68
  69   void AddObserver(CertLoader::Observer* observer);
  70   void RemoveObserver(CertLoader::Observer* observer);
  71
  72   int TPMTokenSlotID() const;
  73   bool IsHardwareBacked() const;
  74
  75   // Whether the certificate is hardware backed. Returns false if the CertLoader
  76   // was not yet started (both |CertificatesLoading()| and
  77   // |certificates_loaded()| are false).
  78   bool IsCertificateHardwareBacked(const net::X509Certificate* cert) const;
  79
  80   // Returns true when the certificate list has been requested but not loaded.
  81   bool CertificatesLoading() const;
  82
  83   bool certificates_loaded() const { return certificates_loaded_; }
  84
  85   // This will be empty until certificates_loaded() is true.
  86   const net::CertificateList& cert_list() const { return *cert_list_; }
  87
  88   void force_hardware_backed_for_test() {
  89     force_hardware_backed_for_test_ = true;
  90   }
  91
  92  private:
  93   CertLoader();
  94   virtual ~CertLoader();
  95
  96   // Trigger a certificate load. If a certificate loading task is already in
  97   // progress, will start a reload once the current task is finished.
  98   void LoadCertificates();
  99
 100   // Called if a certificate load task is finished.
 101   void UpdateCertificates(scoped_ptr<net::CertificateList> cert_list);
 102
 103   void NotifyCertificatesLoaded(bool initial_load);
 104
 105   // net::CertDatabase::Observer
 106   virtual void OnCACertChanged(const net::X509Certificate* cert) OVERRIDE;
 107   virtual void OnCertAdded(const net::X509Certificate* cert) OVERRIDE;
 108   virtual void OnCertRemoved(const net::X509Certificate* cert) OVERRIDE;
 109
 110   ObserverList<Observer> observers_;
 111
 112   // Flags describing current CertLoader state.
 113   bool certificates_loaded_;
 114   bool certificates_update_required_;
 115   bool certificates_update_running_;
 116
 117   // The user-specific NSS certificate database from which the certificates
 118   // should be loaded.
 119   net::NSSCertDatabase* database_;
 120
 121   // Set during tests if |IsHardwareBacked()| should always return true.
 122   bool force_hardware_backed_for_test_;
 123
 124   // Cached Certificates loaded from the database.
 125   scoped_ptr<net::CertificateList> cert_list_;
 126
 127   base::ThreadChecker thread_checker_;
 128
 129   base::WeakPtrFactory<CertLoader> weak_factory_;
 130
 131   DISALLOW_COPY_AND_ASSIGN(CertLoader);
 132 };
 133
 134 }  // namespace chromeos
 135
 136 #endif  // CHROMEOS_CERT_LOADER_H_