// Copyright (c) 2011 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. // PacFileFetcher is an async interface for fetching a proxy auto config // script. It is specific to fetching a PAC script; enforces timeout, max-size, // status code. #ifndef NET_PROXY_RESOLUTION_PAC_FILE_FETCHER_H_ #define NET_PROXY_RESOLUTION_PAC_FILE_FETCHER_H_ #include #include "net/base/completion_once_callback.h" #include "net/base/isolation_info.h" #include "net/base/net_export.h" #include "net/traffic_annotation/network_traffic_annotation.h" class GURL; namespace net { class URLRequestContext; // Interface for downloading a PAC script. Implementations can enforce // timeouts, maximum size constraints, content encoding, etc.. class NET_EXPORT_PRIVATE PacFileFetcher { public: PacFileFetcher(); PacFileFetcher(const PacFileFetcher&) = delete; PacFileFetcher& operator=(const PacFileFetcher&) = delete; // Destruction should cancel any outstanding requests. virtual ~PacFileFetcher(); // Downloads the given PAC URL, and invokes |callback| on completion. // Returns OK on success, otherwise the error code. If the return code is // ERR_IO_PENDING, then the request completes asynchronously, and |callback| // will be invoked later with the final error code. // After synchronous or asynchronous completion with a result code of OK, // |*utf16_text| is filled with the response. On failure, the result text is // an empty string, and the result code is a network error. Some special // network errors that may occur are: // // ERR_TIMED_OUT -- the fetch took too long to complete. // ERR_FILE_TOO_BIG -- the response's body was too large. // ERR_HTTP_RESPONSE_CODE_FAILURE -- non-200 HTTP status code. // ERR_NOT_IMPLEMENTED -- the response required authentication. // // If the request is cancelled (either using the "Cancel()" method or by // deleting |this|), then no callback is invoked. // // Only one fetch is allowed to be outstanding at a time. virtual int Fetch(const GURL& url, std::u16string* utf16_text, CompletionOnceCallback callback, const NetworkTrafficAnnotationTag traffic_annotation) = 0; // Aborts the in-progress fetch (if any). virtual void Cancel() = 0; // Returns the request context that this fetcher uses to issue downloads, // or NULL. virtual URLRequestContext* GetRequestContext() const = 0; // Fails the in-progress fetch (if any) and future requests will fail // immediately. GetRequestContext() will always return nullptr after this is // called. Must be called before the URLRequestContext the fetcher was // created with is torn down. virtual void OnShutdown() = 0; const IsolationInfo& isolation_info() const { return isolation_info_; } private: // Transient IsolationInfo used to fetch PAC scripts and resolve hostnames. // Safe to reuse because delays for WPAD fetches don't provide information // to the web platform useful to attackers, and WPAD fetches uniformly // block all network requests. const IsolationInfo isolation_info_ = IsolationInfo::CreateTransient(); }; } // namespace net #endif // NET_PROXY_RESOLUTION_PAC_FILE_FETCHER_H_