blob: 851b5624cf7b5ed67ea5bf9a51a63d4a36b9bade [file] [log] [blame]
// Copyright 2018 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 <vector>
#include "base/compiler_specific.h"
#include "base/macros.h"
#include "base/memory/ref_counted.h"
#include "base/memory/weak_ptr.h"
#include "base/observer_list.h"
#include "base/threading/thread_checker.h"
#include "chromeos/chromeos_export.h"
#include "chromeos/policy_certificate_provider.h"
#include "net/cert/scoped_nss_types.h"
namespace net {
class NSSCertDatabase;
namespace chromeos {
// This class is responsible for 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 and tpm token is
// initialized), or the cert database changes, observers are called with
// OnCertificatesLoaded().
// This class supports using one or two cert databases. The expected usage is
// that NetworkCertLoader is used with a NSSCertDatabase backed by the system
// token before user sign-in, and additionally with a user-specific
// NSSCertDatabase after user sign-in. When both NSSCertDatabase are used,
// NetworkCertLoader combines certificates from both into |all_certs()|.
class CHROMEOS_EXPORT NetworkCertLoader
: public PolicyCertificateProvider::Observer {
class Observer {
// Called when the certificates, passed for convenience as |all_certs|,
// have completed loading.
virtual void OnCertificatesLoaded(
const net::ScopedCERTCertificateList& all_certs) = 0;
virtual ~Observer() {}
// Sets the global instance. Must be called before any calls to Get().
static void Initialize();
// Destroys the global instance.
static void Shutdown();
// Gets the global instance. Initialize() must be called first.
static NetworkCertLoader* Get();
// Returns true if the global instance has been initialized.
static bool IsInitialized();
// Returns the PKCS#11 attribute CKA_ID for a certificate as an upper-case
// hex string and sets |slot_id| to the id of the containing slot, or returns
// an empty string and doesn't modify |slot_id| if the PKCS#11 id could not be
// determined.
static std::string GetPkcs11IdAndSlotForCert(CERTCertificate* cert,
int* slot_id);
// When this is called, |NetworkCertLoader| stops sending out updates to its
// observers. This is a workaround for, where a crash
// is suspected to happen due to updates sent out during the shutdown
// procedure. TODO( Remove this when the root cause
// is found.
void set_is_shutting_down() { is_shutting_down_ = true; }
// Sets the NSS cert database which NetworkCertLoader should use to access
// system slot certificates. The NetworkCertLoader will _not_ take ownership
// of the database - see comment on SetUserNSSDB. NetworkCertLoader supports
// working with only one database or with both (system and user) databases.
void SetSystemNSSDB(net::NSSCertDatabase* system_slot_database);
// Sets the NSS cert database which NetworkCertLoader should use to access
// user slot certificates. NetworkCertLoader understands the edge case that
// this database could also give access to system slot certificates (e.g. for
// affiliated users). The NetworkCertLoader will _not_ take the ownership of
// the database, but it expects it to stay alive at least until the shutdown
// starts on the main thread. This assumes that SetUserNSSDB and other methods
// directly using |database_| are not called during shutdown.
// NetworkCertLoader supports working with only one database or with both
// (system and user) databases.
void SetUserNSSDB(net::NSSCertDatabase* user_database);
// Adds the passed |PolicyCertificateProvider| and starts using the authority
// certificates provided by it. NetworkCertLoader registers itself as Observer
// on |policy_certificate_provider|, so the caller must ensure to call
// |RemovePolicyCertificateProvider| before |policy_certificate_provider| is
// destroyed or before |NetworkCertLoader| is shut down.
void AddPolicyCertificateProvider(
PolicyCertificateProvider* policy_certificate_provider);
// Removes the passed |PolicyCertificateProvider| and stops using authority
// certificates provided by it. |policy_certificate_provider| must have been
// added using |AddPolicyCertificateProvider| before.
void RemovePolicyCertificateProvider(
PolicyCertificateProvider* policy_certificate_provider);
void AddObserver(NetworkCertLoader::Observer* observer);
void RemoveObserver(NetworkCertLoader::Observer* observer);
// Returns true if |cert| is hardware backed. See also
// ForceHardwareBackedForTesting().
static bool IsCertificateHardwareBacked(CERTCertificate* cert);
// Returns true when the certificate list has been requested but not loaded.
// When two databases are in use (SetSystemNSSDB and SetUserNSSDB have both
// been called), this returns true when at least one of them is currently
// loading certificates.
// Note that this method poses an exception in the NetworkCertLoader
// interface: While most of NetworkCertLoader's interface treats the initial
// load of a second database the same way as an update in the first database,
// this method does not. The reason is that it's targeted at displaying a
// message in the GUI, so the user knows that (more) certificates will be
// available soon.
bool initial_load_of_any_database_running() const;
// Returns true if any certificates have been loaded. If NetworkCertLoader
// uses a system and a user NSS database, this returns true after the
// certificates from the first (usually system) database have been loaded.
bool initial_load_finished() const;
// Returns true if certificates from a user NSS database have been loaded.
bool user_cert_database_load_finished() const;
// Returns all certificates. This will be empty until certificates_loaded() is
// true.
const net::ScopedCERTCertificateList& all_certs() const {
return all_certs_;
// Returns certificates from the system token. This will be empty until
// certificates_loaded() is true.
const net::ScopedCERTCertificateList& system_token_client_certs() const {
return system_token_client_certs_;
// Called in tests if |IsCertificateHardwareBacked()| should always return
// true.
static void ForceHardwareBackedForTesting();
class CertCache;
~NetworkCertLoader() override;
// Called when |system_cert_cache_| or |user_cert_cache| certificates have
// potentially changed.
void OnCertCacheUpdated();
// Called as a result of |OnCertCacheUpdated|. This is a separate function,
// because |OnCertCacheUpdated| may trigger a background task for filtering
// certificates.
void StoreCertsFromCache(
net::ScopedCERTCertificateList all_certs,
net::ScopedCERTCertificateList system_token_client_certs);
// Called when policy-provided certificates or cache-based certificates (see
// |all_certs_from_cache_|) have potentially changed.
void UpdateCertificates();
void NotifyCertificatesLoaded();
// PolicyCertificateProvider::Observer
void OnPolicyProvidedCertsChanged(
const net::CertificateList& all_server_and_authority_certs,
const net::CertificateList& trust_anchors) override;
// If this is true, |NetworkCertLoader| does not send out notifications to its
// observers anymore.
bool is_shutting_down_ = false;
base::ObserverList<Observer>::Unchecked observers_;
// Cache for certificates from the system-token NSSCertDatabase.
std::unique_ptr<CertCache> system_cert_cache_;
// Cache for certificates from the user-specific NSSCertDatabase.
std::unique_ptr<CertCache> user_cert_cache_;
// Cached certificates loaded from the database(s) and policy-pushed Authority
// certificates.
net::ScopedCERTCertificateList all_certs_;
// Cached certificates loaded from the database(s).
net::ScopedCERTCertificateList all_certs_from_cache_;
// Cached certificates from system token.
net::ScopedCERTCertificateList system_token_client_certs_;
// True if |StoreCertsFromCache()| was called before.
bool certs_from_cache_loaded_ = false;
std::vector<const PolicyCertificateProvider*> policy_certificate_providers_;
base::WeakPtrFactory<NetworkCertLoader> weak_factory_;
} // namespace chromeos