components/policy/core/common/proxy_policy_provider.h

   1 // Copyright 2014 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 COMPONENTS_POLICY_CORE_COMMON_PROXY_POLICY_PROVIDER_H_
   6 #define COMPONENTS_POLICY_CORE_COMMON_PROXY_POLICY_PROVIDER_H_
   7
   8 #include "base/basictypes.h"
   9 #include "components/policy/core/common/configuration_policy_provider.h"
  10 #include "components/policy/policy_export.h"
  11
  12 namespace policy {
  13
  14 // A policy provider implementation that acts as a proxy for another policy
  15 // provider, swappable at any point.
  16 //
  17 // Note that ProxyPolicyProvider correctly forwards RefreshPolicies() calls to
  18 // the delegate if present. If there is no delegate, the refresh results in an
  19 // immediate (empty) policy update.
  20 //
  21 // Furthermore, IsInitializationComplete() is implemented trivially - it always
  22 // returns true. Given that the delegate may be swapped at any point, there's no
  23 // point in trying to carry over initialization status from the delegate.
  24 //
  25 // This policy provider implementation is used to inject browser-global policy
  26 // originating from the user policy configured on the primary Chrome OS user
  27 // (i.e. the user logging in from the login screen). This way, policy settings
  28 // on the primary user propagate into g_browser_process->local_state_().
  29 //
  30 // The bizarre situation of user-scoped policy settings which are implemented
  31 // browser-global wouldn't exist in an ideal world. However, for historic
  32 // and technical reasons there are policy settings that are scoped to the user
  33 // but are implemented to take effect for the entire browser instance. A good
  34 // example for this are policies that affect the Chrome network stack in areas
  35 // where there's no profile-specific context. The meta data in
  36 // policy_templates.json allows to identify the policies in this bucket; they'll
  37 // have per_profile set to False, supported_on including chrome_os, and
  38 // dynamic_refresh set to True.
  39 class POLICY_EXPORT ProxyPolicyProvider
  40     : public ConfigurationPolicyProvider,
  41       public ConfigurationPolicyProvider::Observer {
  42  public:
  43   ProxyPolicyProvider();
  44   ~ProxyPolicyProvider() override;
  45
  46   // Updates the provider this proxy delegates to.
  47   void SetDelegate(ConfigurationPolicyProvider* delegate);
  48
  49   // ConfigurationPolicyProvider:
  50   void Shutdown() override;
  51   void RefreshPolicies() override;
  52
  53   // ConfigurationPolicyProvider::Observer:
  54   void OnUpdatePolicy(ConfigurationPolicyProvider* provider) override;
  55
  56  private:
  57   ConfigurationPolicyProvider* delegate_;
  58
  59   DISALLOW_COPY_AND_ASSIGN(ProxyPolicyProvider);
  60 };
  61
  62 }  // namespace policy
  63
  64 #endif  // COMPONENTS_POLICY_CORE_COMMON_PROXY_POLICY_PROVIDER_H_