1c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)// Copyright (c) 2013 The Chromium Authors. All rights reserved. 2c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)// Use of this source code is governed by a BSD-style license that can be 3c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)// found in the LICENSE file. 4c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 5a3f6a49ab37290eeeb8db0f41ec0f1cb74a68be7Torne (Richard Coles)#ifndef COMPONENTS_POLICY_CORE_COMMON_CLOUD_EXTERNAL_POLICY_DATA_UPDATER_H_ 6a3f6a49ab37290eeeb8db0f41ec0f1cb74a68be7Torne (Richard Coles)#define COMPONENTS_POLICY_CORE_COMMON_CLOUD_EXTERNAL_POLICY_DATA_UPDATER_H_ 7c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 8c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)#include <map> 9c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)#include <queue> 10c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)#include <string> 11c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 12c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)#include "base/basictypes.h" 13c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)#include "base/callback_forward.h" 14c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)#include "base/memory/ref_counted.h" 1558537e28ecd584eab876aee8be7156509866d23aTorne (Richard Coles)#include "base/memory/scoped_ptr.h" 16c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)#include "base/memory/weak_ptr.h" 17a3f6a49ab37290eeeb8db0f41ec0f1cb74a68be7Torne (Richard Coles)#include "components/policy/policy_export.h" 18c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 19c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)namespace base { 20c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)class SequencedTaskRunner; 21c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)} 22c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 23c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)namespace policy { 24c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 2558537e28ecd584eab876aee8be7156509866d23aTorne (Richard Coles)class ExternalPolicyDataFetcher; 2658537e28ecd584eab876aee8be7156509866d23aTorne (Richard Coles) 27c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)// This class downloads external policy data. Given a |Request|, data is fetched 28c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)// from the |url|, verified to not exceed |max_size| and to match the expected 29c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)// |hash| and then handed to a callback that can do further verification before 30c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)// finally deciding whether the fetched data is valid. 31c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)// If a fetch is not successful or retrieves invalid data, retries are scheduled 32c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)// with exponential backoff. 3358537e28ecd584eab876aee8be7156509866d23aTorne (Richard Coles)// The actual fetching is handled by an ExternalPolicyDataFetcher, allowing this 3458537e28ecd584eab876aee8be7156509866d23aTorne (Richard Coles)// class to run on a background thread where network I/O is not possible. 35a3f6a49ab37290eeeb8db0f41ec0f1cb74a68be7Torne (Richard Coles)class POLICY_EXPORT ExternalPolicyDataUpdater { 36c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) public: 37a3f6a49ab37290eeeb8db0f41ec0f1cb74a68be7Torne (Richard Coles) struct POLICY_EXPORT Request { 38c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) public: 39c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) Request(); 40c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) Request(const std::string& url, const std::string& hash, int64 max_size); 41c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 42c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) bool operator==(const Request& other) const; 43c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 44c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) std::string url; 45c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) std::string hash; 46c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) int64 max_size; 47c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) }; 48c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 49c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // This callback is invoked when a fetch has successfully retrieved |data| 50c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // that does not exceed |max_size| and matches the expected |hash|. The 51c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // callback can do further verification to decide whether the fetched data is 52c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // valid. 53c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // If the callback returns |true|, the data is accepted and the |Request| is 54c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // finished. If the callback returns |false|, the data is rejected and the 55c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // fetch is retried after a long backoff. Note that in this case, the callback 56c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // may be invoked multiple times as the fetch is repeated. Make sure to not 57c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // bind base::Passed() scoped_ptrs to the callback in such cases as these 58c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // become invalid after a callback has been run once. base::Owned() can be 59c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // used in all cases. 60c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) typedef base::Callback<bool(const std::string&)> FetchSuccessCallback; 61c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 6258537e28ecd584eab876aee8be7156509866d23aTorne (Richard Coles) // This class runs on the background thread represented by |task_runner|, 6358537e28ecd584eab876aee8be7156509866d23aTorne (Richard Coles) // which must support file I/O. All network I/O is forwarded to a different 6458537e28ecd584eab876aee8be7156509866d23aTorne (Richard Coles) // thread by the |external_policy_data_fetcher|. 65c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) ExternalPolicyDataUpdater( 66c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) scoped_refptr<base::SequencedTaskRunner> task_runner, 6758537e28ecd584eab876aee8be7156509866d23aTorne (Richard Coles) scoped_ptr<ExternalPolicyDataFetcher> external_policy_data_fetcher, 68c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) size_t max_parallel_fetches); 69c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) ~ExternalPolicyDataUpdater(); 70c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 71c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // Fetches the external data specified in the |request|. The |key| is an 72c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // opaque identifier. If another request for the same |key| is still pending, 73c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // it will be canceled and replaced with the new |request|. The callback will 74c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // be invoked after a successful fetch. See the documentation of 75c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // |FetchSuccessCallback| for more details. 76c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) void FetchExternalData(const std::string key, 77c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) const Request& request, 78c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) const FetchSuccessCallback& callback); 79c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 80c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // Cancels the pending request identified by |key|. If no such request is 81c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // pending, does nothing. 82c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) void CancelExternalDataFetch(const std::string& key); 83c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 84c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) private: 85c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) class FetchJob; 86c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 87c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // Starts jobs from the |job_queue_| until |max_parallel_jobs_| are running or 88c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // the queue is depleted. 89c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) void StartNextJobs(); 90c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 91c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // Appends |job| to the |job_queue_| and starts it immediately if less than 92c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // |max_parallel_jobs_| are running. 93c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) void ScheduleJob(FetchJob* job); 94c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 95c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // Callback for jobs that succeeded. 96c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) void OnJobSucceeded(FetchJob* job); 97c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 98c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // Callback for jobs that failed. 99c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) void OnJobFailed(FetchJob* job); 100c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 101c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) scoped_refptr<base::SequencedTaskRunner> task_runner_; 10258537e28ecd584eab876aee8be7156509866d23aTorne (Richard Coles) scoped_ptr<ExternalPolicyDataFetcher> external_policy_data_fetcher_; 103c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 104c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // The maximum number of jobs to run in parallel. 105c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) size_t max_parallel_jobs_; 106c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 107c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // The number of jobs currently running. 108c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) size_t running_jobs_; 109c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 110c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // Queue of jobs waiting to be run. Jobs are taken off the queue and started 111c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // by StartNextJobs(). 112c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) std::queue<base::WeakPtr<FetchJob> > job_queue_; 113c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 114c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // Map that owns all existing jobs, regardless of whether they are currently 115c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // queued, running or waiting for a retry. 116c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) std::map<std::string, FetchJob*> job_map_; 117c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 118c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // |True| once the destructor starts. Prevents jobs from being started during 119c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) // shutdown. 120c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) bool shutting_down_; 121c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 122c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) DISALLOW_COPY_AND_ASSIGN(ExternalPolicyDataUpdater); 123c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)}; 124c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 125c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles)} // namespace policy 126c2e0dbddbe15c98d52c4786dac06cb8952a8ae6dTorne (Richard Coles) 127a3f6a49ab37290eeeb8db0f41ec0f1cb74a68be7Torne (Richard Coles)#endif // COMPONENTS_POLICY_CORE_COMMON_CLOUD_EXTERNAL_POLICY_DATA_UPDATER_H_ 128