| // Copyright (c) 2012 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. |
| |
| #ifndef CONTENT_BROWSER_LOADER_MIME_SNIFFING_RESOURCE_HANDLER_H_ |
| #define CONTENT_BROWSER_LOADER_MIME_SNIFFING_RESOURCE_HANDLER_H_ |
| |
| #include <string> |
| #include <vector> |
| |
| #include "base/auto_reset.h" |
| #include "base/macros.h" |
| #include "base/memory/weak_ptr.h" |
| #include "content/browser/loader/layered_resource_handler.h" |
| #include "content/browser/loader/resource_controller.h" |
| #include "content/common/content_export.h" |
| #include "ppapi/buildflags/buildflags.h" |
| #include "third_party/blink/public/mojom/fetch/fetch_api_request.mojom.h" |
| |
| namespace net { |
| class URLRequest; |
| } |
| |
| namespace content { |
| class InterceptingResourceHandler; |
| class PluginService; |
| class ResourceController; |
| class ResourceDispatcherHostImpl; |
| struct WebPluginInfo; |
| |
| // ResourceHandler that, if necessary, buffers a response body without passing |
| // it to the next ResourceHandler until it can perform mime sniffing on it. |
| // |
| // Uses the buffer provided by the original event handler for buffering, and |
| // continues to reuses it until it can determine the MIME type |
| // subsequent reads until it's done buffering. As a result, the buffer |
| // returned by the next ResourceHandler must have a capacity of at least |
| // net::kMaxBytesToSniff * 2. |
| // |
| // Before a request is sent, this ResourceHandler will also set an appropriate |
| // Accept header on the request based on its ResourceType, if one isn't already |
| // present. |
| class CONTENT_EXPORT MimeSniffingResourceHandler |
| : public LayeredResourceHandler { |
| public: |
| MimeSniffingResourceHandler( |
| std::unique_ptr<ResourceHandler> next_handler, |
| ResourceDispatcherHostImpl* host, |
| PluginService* plugin_service, |
| InterceptingResourceHandler* intercepting_handler, |
| net::URLRequest* request, |
| blink::mojom::RequestContextType request_context_type); |
| ~MimeSniffingResourceHandler() override; |
| |
| private: |
| class Controller; |
| |
| friend class MimeSniffingResourceHandlerTest; |
| enum State { |
| // Starting state of the MimeSniffingResourceHandler. In this state, it is |
| // acting as a blind pass-through ResourceHandler until the response is |
| // received. |
| STATE_STARTING, |
| |
| // In this state, the MimeSniffingResourceHandler is buffering the response |
| // data in read_buffer_, waiting to sniff the mime type and make a choice |
| // about request interception. |
| STATE_BUFFERING, |
| |
| // In these states, the MimeSniffingResourceHandler is calling OnWillRead on |
| // the downstream ResourceHandler and then waiting for the response. |
| STATE_CALLING_ON_WILL_READ, |
| STATE_WAITING_FOR_BUFFER, |
| |
| // In this state, the MimeSniffingResourceHandler has identified the mime |
| // type and made a decision on whether the request should be intercepted or |
| // not. It is nows attempting to replay the response to downstream |
| // handlers. |
| STATE_INTERCEPTION_CHECK_DONE, |
| |
| // In this state, the MimeSniffingResourceHandler is replaying the buffered |
| // OnResponseStarted event to the downstream ResourceHandlers. |
| STATE_REPLAYING_RESPONSE_RECEIVED, |
| |
| // In these states, the MimeSniffingResourceHandler is replaying the pair of |
| // OnWillRead + OnReadCompleted(0) calls that indicates end of the response |
| // body. See also |need_to_replay_extra_eof_packet_|. |
| STATE_REPLAYING_EOF_WILL_READ, |
| STATE_REPLAYING_EOF_READ_COMPLETED, |
| |
| // In this state, the MimeSniffingResourceHandler is just a blind |
| // pass-through |
| // ResourceHandler. |
| STATE_STREAMING, |
| }; |
| |
| // ResourceHandler implementation: |
| void OnWillStart(const GURL&, |
| std::unique_ptr<ResourceController> controller) override; |
| void OnResponseStarted( |
| network::ResourceResponse* response, |
| std::unique_ptr<ResourceController> controller) override; |
| void OnWillRead(scoped_refptr<net::IOBuffer>* buf, |
| int* buf_size, |
| std::unique_ptr<ResourceController> controller) override; |
| void OnReadCompleted(int bytes_read, |
| std::unique_ptr<ResourceController> controller) override; |
| void OnResponseCompleted( |
| const net::URLRequestStatus& status, |
| std::unique_ptr<ResourceController> controller) override; |
| |
| void ResumeInternal(); |
| |
| // -------------------------------------------------------------------------- |
| // The following methods replay the buffered data to the downstream |
| // ResourceHandlers. They return false if the request should be cancelled, |
| // true otherwise. Each of them will set |defer| to true if the request will |
| // proceed to the next stage asynchronously. |
| |
| // Used to advance through the states of the state machine. |
| void AdvanceState(); |
| |
| // Intercepts the request as a stream/download if needed. |
| void MaybeIntercept(); |
| |
| // Calls OnWillRead on the downstream handlers. |
| void CallOnWillRead(); |
| |
| // Copies received buffer to parent. |
| void BufferReceived(); |
| |
| // Replays OnResponseStarted on the downstream handlers. |
| void ReplayResponseReceived(); |
| |
| // Replays OnReadCompleted on the downstreams handlers. |
| void ReplayReadCompleted(); |
| |
| // Replays OnWillRead if needed to notify the downstream handler about EOF. |
| void ReplayWillReadEof(); |
| |
| // Replays OnReadCompleted(0) if needed to notify the downstream handler about |
| // EOF. |
| void ReplayReadCompletedEof(); |
| |
| // -------------------------------------------------------------------------- |
| |
| // Checks whether this request should be intercepted as a stream or a |
| // download. If this is the case, sets up the new ResourceHandler that will be |
| // used for interception. |
| // |
| // Returns true on synchronous success, false if the operation will need to |
| // complete asynchronously or failure. On failure, also cancels the request. |
| bool MaybeStartInterception(); |
| |
| // Determines whether a plugin will handle the current request. Returns false |
| // if there is an error and the request should be cancelled and true |
| // otherwise. If the request is directed to a plugin, |handled_by_plugin| is |
| // set to true. |
| // |
| // Returns true on synchronous success, false if the operation will need to |
| // complete asynchronously or failure. On failure, also cancels the request. |
| bool CheckForPluginHandler(bool* handled_by_plugin); |
| |
| // Whether this request is allowed to be intercepted as a download or a |
| // stream. |
| bool CanBeIntercepted(); |
| |
| // Whether the response we received is not provisional. |
| bool CheckResponseIsNotProvisional(); |
| |
| bool MustDownload(); |
| |
| // Called on the IO thread once the list of plugins has been loaded. |
| void OnPluginsLoaded(const std::vector<WebPluginInfo>& plugins); |
| |
| State state_; |
| |
| ResourceDispatcherHostImpl* host_; |
| #if BUILDFLAG(ENABLE_PLUGINS) |
| PluginService* plugin_service_; |
| #endif |
| |
| bool must_download_; |
| bool must_download_is_set_; |
| |
| // Used to buffer the response received until replay. |
| scoped_refptr<network::ResourceResponse> response_; |
| scoped_refptr<net::IOBuffer> read_buffer_; |
| int read_buffer_size_; |
| int bytes_read_; |
| bool need_to_replay_extra_eof_packet_; |
| |
| // Pointers to parent-owned read buffer and its size. Only used for first |
| // OnWillRead call. |
| scoped_refptr<net::IOBuffer>* parent_read_buffer_; |
| int* parent_read_buffer_size_; |
| |
| // The InterceptingResourceHandler that will perform ResourceHandler swap if |
| // needed. |
| InterceptingResourceHandler* intercepting_handler_; |
| |
| blink::mojom::RequestContextType request_context_type_; |
| |
| // True if current in an AdvanceState loop. Used to prevent re-entrancy and |
| // avoid an extra PostTask. |
| bool in_state_loop_; |
| // Set to true if Resume() is called while |in_state_loop_| is true. When |
| // returning to the parent AdvanceState loop, will synchronously advance to |
| // the next state when control returns to the AdvanceState loop. |
| bool advance_state_; |
| |
| base::WeakPtrFactory<MimeSniffingResourceHandler> weak_ptr_factory_{this}; |
| |
| DISALLOW_COPY_AND_ASSIGN(MimeSniffingResourceHandler); |
| }; |
| |
| } // namespace content |
| |
| #endif // CONTENT_BROWSER_LOADER_MIME_SNIFFING_RESOURCE_HANDLER_H_ |