net/websockets/websocket_channel.cc

   1 // Copyright 2013 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 #include "net/websockets/websocket_channel.h"
   6
   7 #include <limits.h>  // for INT_MAX
   8
   9 #include <algorithm>
  10 #include <deque>
  11
  12 #include "base/basictypes.h"  // for size_t
  13 #include "base/big_endian.h"
  14 #include "base/bind.h"
  15 #include "base/compiler_specific.h"
  16 #include "base/memory/ref_counted.h"
  17 #include "base/memory/weak_ptr.h"
  18 #include "base/message_loop/message_loop.h"
  19 #include "base/metrics/histogram.h"
  20 #include "base/numerics/safe_conversions.h"
  21 #include "base/stl_util.h"
  22 #include "base/strings/stringprintf.h"
  23 #include "base/time/time.h"
  24 #include "net/base/io_buffer.h"
  25 #include "net/base/net_log.h"
  26 #include "net/http/http_request_headers.h"
  27 #include "net/http/http_response_headers.h"
  28 #include "net/http/http_util.h"
  29 #include "net/websockets/websocket_errors.h"
  30 #include "net/websockets/websocket_event_interface.h"
  31 #include "net/websockets/websocket_frame.h"
  32 #include "net/websockets/websocket_handshake_request_info.h"
  33 #include "net/websockets/websocket_handshake_response_info.h"
  34 #include "net/websockets/websocket_mux.h"
  35 #include "net/websockets/websocket_stream.h"
  36 #include "url/origin.h"
  37
  38 namespace net {
  39
  40 namespace {
  41
  42 using base::StreamingUtf8Validator;
  43
  44 const int kDefaultSendQuotaLowWaterMark = 1 << 16;
  45 const int kDefaultSendQuotaHighWaterMark = 1 << 17;
  46 const size_t kWebSocketCloseCodeLength = 2;
  47 // This timeout is based on TCPMaximumSegmentLifetime * 2 from
  48 // MainThreadWebSocketChannel.cpp in Blink.
  49 const int kClosingHandshakeTimeoutSeconds = 2 * 2 * 60;
  50
  51 typedef WebSocketEventInterface::ChannelState ChannelState;
  52 const ChannelState CHANNEL_ALIVE = WebSocketEventInterface::CHANNEL_ALIVE;
  53 const ChannelState CHANNEL_DELETED = WebSocketEventInterface::CHANNEL_DELETED;
  54
  55 // Maximum close reason length = max control frame payload -
  56 //                               status code length
  57 //                             = 125 - 2
  58 const size_t kMaximumCloseReasonLength = 125 - kWebSocketCloseCodeLength;
  59
  60 // Check a close status code for strict compliance with RFC6455. This is only
  61 // used for close codes received from a renderer that we are intending to send
  62 // out over the network. See ParseClose() for the restrictions on incoming close
  63 // codes. The |code| parameter is type int for convenience of implementation;
  64 // the real type is uint16. Code 1005 is treated specially; it cannot be set
  65 // explicitly by Javascript but the renderer uses it to indicate we should send
  66 // a Close frame with no payload.
  67 bool IsStrictlyValidCloseStatusCode(int code) {
  68   static const int kInvalidRanges[] = {
  69       // [BAD, OK)
  70       0,    1000,   // 1000 is the first valid code
  71       1006, 1007,   // 1006 MUST NOT be set.
  72       1014, 3000,   // 1014 unassigned; 1015 up to 2999 are reserved.
  73       5000, 65536,  // Codes above 5000 are invalid.
  74   };
  75   const int* const kInvalidRangesEnd =
  76       kInvalidRanges + arraysize(kInvalidRanges);
  77
  78   DCHECK_GE(code, 0);
  79   DCHECK_LT(code, 65536);
  80   const int* upper = std::upper_bound(kInvalidRanges, kInvalidRangesEnd, code);
  81   DCHECK_NE(kInvalidRangesEnd, upper);
  82   DCHECK_GT(upper, kInvalidRanges);
  83   DCHECK_GT(*upper, code);
  84   DCHECK_LE(*(upper - 1), code);
  85   return ((upper - kInvalidRanges) % 2) == 0;
  86 }
  87
  88 // This function avoids a bunch of boilerplate code.
  89 void AllowUnused(ChannelState ALLOW_UNUSED unused) {}
  90
  91 // Sets |name| to the name of the frame type for the given |opcode|. Note that
  92 // for all of Text, Binary and Continuation opcode, this method returns
  93 // "Data frame".
  94 void GetFrameTypeForOpcode(WebSocketFrameHeader::OpCode opcode,
  95                            std::string* name) {
  96   switch (opcode) {
  97     case WebSocketFrameHeader::kOpCodeText:    // fall-thru
  98     case WebSocketFrameHeader::kOpCodeBinary:  // fall-thru
  99     case WebSocketFrameHeader::kOpCodeContinuation:
 100       *name = "Data frame";
 101       break;
 102
 103     case WebSocketFrameHeader::kOpCodePing:
 104       *name = "Ping";
 105       break;
 106
 107     case WebSocketFrameHeader::kOpCodePong:
 108       *name = "Pong";
 109       break;
 110
 111     case WebSocketFrameHeader::kOpCodeClose:
 112       *name = "Close";
 113       break;
 114
 115     default:
 116       *name = "Unknown frame type";
 117       break;
 118   }
 119
 120   return;
 121 }
 122
 123 }  // namespace
 124
 125 // A class to encapsulate a set of frames and information about the size of
 126 // those frames.
 127 class WebSocketChannel::SendBuffer {
 128  public:
 129   SendBuffer() : total_bytes_(0) {}
 130
 131   // Add a WebSocketFrame to the buffer and increase total_bytes_.
 132   void AddFrame(scoped_ptr<WebSocketFrame> chunk);
 133
 134   // Return a pointer to the frames_ for write purposes.
 135   ScopedVector<WebSocketFrame>* frames() { return &frames_; }
 136
 137  private:
 138   // The frames_ that will be sent in the next call to WriteFrames().
 139   ScopedVector<WebSocketFrame> frames_;
 140
 141   // The total size of the payload data in |frames_|. This will be used to
 142   // measure the throughput of the link.
 143   // TODO(ricea): Measure the throughput of the link.
 144   size_t total_bytes_;
 145 };
 146
 147 void WebSocketChannel::SendBuffer::AddFrame(scoped_ptr<WebSocketFrame> frame) {
 148   total_bytes_ += frame->header.payload_length;
 149   frames_.push_back(frame.release());
 150 }
 151
 152 // Implementation of WebSocketStream::ConnectDelegate that simply forwards the
 153 // calls on to the WebSocketChannel that created it.
 154 class WebSocketChannel::ConnectDelegate
 155     : public WebSocketStream::ConnectDelegate {
 156  public:
 157   explicit ConnectDelegate(WebSocketChannel* creator) : creator_(creator) {}
 158
 159   virtual void OnSuccess(scoped_ptr<WebSocketStream> stream) OVERRIDE {
 160     creator_->OnConnectSuccess(stream.Pass());
 161     // |this| may have been deleted.
 162   }
 163
 164   virtual void OnFailure(const std::string& message) OVERRIDE {
 165     creator_->OnConnectFailure(message);
 166     // |this| has been deleted.
 167   }
 168
 169   virtual void OnStartOpeningHandshake(
 170       scoped_ptr<WebSocketHandshakeRequestInfo> request) OVERRIDE {
 171     creator_->OnStartOpeningHandshake(request.Pass());
 172   }
 173
 174   virtual void OnFinishOpeningHandshake(
 175       scoped_ptr<WebSocketHandshakeResponseInfo> response) OVERRIDE {
 176     creator_->OnFinishOpeningHandshake(response.Pass());
 177   }
 178
 179   virtual void OnSSLCertificateError(
 180       scoped_ptr<WebSocketEventInterface::SSLErrorCallbacks>
 181           ssl_error_callbacks,
 182       const SSLInfo& ssl_info,
 183       bool fatal) OVERRIDE {
 184     creator_->OnSSLCertificateError(
 185         ssl_error_callbacks.Pass(), ssl_info, fatal);
 186   }
 187
 188  private:
 189   // A pointer to the WebSocketChannel that created this object. There is no
 190   // danger of this pointer being stale, because deleting the WebSocketChannel
 191   // cancels the connect process, deleting this object and preventing its
 192   // callbacks from being called.
 193   WebSocketChannel* const creator_;
 194
 195   DISALLOW_COPY_AND_ASSIGN(ConnectDelegate);
 196 };
 197
 198 class WebSocketChannel::HandshakeNotificationSender
 199     : public base::SupportsWeakPtr<HandshakeNotificationSender> {
 200  public:
 201   explicit HandshakeNotificationSender(WebSocketChannel* channel);
 202   ~HandshakeNotificationSender();
 203
 204   static void Send(base::WeakPtr<HandshakeNotificationSender> sender);
 205
 206   ChannelState SendImmediately(WebSocketEventInterface* event_interface);
 207
 208   const WebSocketHandshakeRequestInfo* handshake_request_info() const {
 209     return handshake_request_info_.get();
 210   }
 211
 212   void set_handshake_request_info(
 213       scoped_ptr<WebSocketHandshakeRequestInfo> request_info) {
 214     handshake_request_info_ = request_info.Pass();
 215   }
 216
 217   const WebSocketHandshakeResponseInfo* handshake_response_info() const {
 218     return handshake_response_info_.get();
 219   }
 220
 221   void set_handshake_response_info(
 222       scoped_ptr<WebSocketHandshakeResponseInfo> response_info) {
 223     handshake_response_info_ = response_info.Pass();
 224   }
 225
 226  private:
 227   WebSocketChannel* owner_;
 228   scoped_ptr<WebSocketHandshakeRequestInfo> handshake_request_info_;
 229   scoped_ptr<WebSocketHandshakeResponseInfo> handshake_response_info_;
 230 };
 231
 232 WebSocketChannel::HandshakeNotificationSender::HandshakeNotificationSender(
 233     WebSocketChannel* channel)
 234     : owner_(channel) {}
 235
 236 WebSocketChannel::HandshakeNotificationSender::~HandshakeNotificationSender() {}
 237
 238 void WebSocketChannel::HandshakeNotificationSender::Send(
 239     base::WeakPtr<HandshakeNotificationSender> sender) {
 240   // Do nothing if |sender| is already destructed.
 241   if (sender) {
 242     WebSocketChannel* channel = sender->owner_;
 243     AllowUnused(sender->SendImmediately(channel->event_interface_.get()));
 244   }
 245 }
 246
 247 ChannelState WebSocketChannel::HandshakeNotificationSender::SendImmediately(
 248     WebSocketEventInterface* event_interface) {
 249
 250   if (handshake_request_info_.get()) {
 251     if (CHANNEL_DELETED == event_interface->OnStartOpeningHandshake(
 252                                handshake_request_info_.Pass()))
 253       return CHANNEL_DELETED;
 254   }
 255
 256   if (handshake_response_info_.get()) {
 257     if (CHANNEL_DELETED == event_interface->OnFinishOpeningHandshake(
 258                                handshake_response_info_.Pass()))
 259       return CHANNEL_DELETED;
 260
 261     // TODO(yhirano): We can release |this| to save memory because
 262     // there will be no more opening handshake notification.
 263   }
 264
 265   return CHANNEL_ALIVE;
 266 }
 267
 268 WebSocketChannel::PendingReceivedFrame::PendingReceivedFrame(
 269     bool final,
 270     WebSocketFrameHeader::OpCode opcode,
 271     const scoped_refptr<IOBuffer>& data,
 272     size_t offset,
 273     size_t size)
 274     : final_(final),
 275       opcode_(opcode),
 276       data_(data),
 277       offset_(offset),
 278       size_(size) {}
 279
 280 WebSocketChannel::PendingReceivedFrame::~PendingReceivedFrame() {}
 281
 282 void WebSocketChannel::PendingReceivedFrame::ResetOpcode() {
 283   DCHECK(WebSocketFrameHeader::IsKnownDataOpCode(opcode_));
 284   opcode_ = WebSocketFrameHeader::kOpCodeContinuation;
 285 }
 286
 287 void WebSocketChannel::PendingReceivedFrame::DidConsume(size_t bytes) {
 288   DCHECK_LE(offset_, size_);
 289   DCHECK_LE(bytes, size_ - offset_);
 290   offset_ += bytes;
 291 }
 292
 293 WebSocketChannel::WebSocketChannel(
 294     scoped_ptr<WebSocketEventInterface> event_interface,
 295     URLRequestContext* url_request_context)
 296     : event_interface_(event_interface.Pass()),
 297       url_request_context_(url_request_context),
 298       send_quota_low_water_mark_(kDefaultSendQuotaLowWaterMark),
 299       send_quota_high_water_mark_(kDefaultSendQuotaHighWaterMark),
 300       current_send_quota_(0),
 301       current_receive_quota_(0),
 302       timeout_(base::TimeDelta::FromSeconds(kClosingHandshakeTimeoutSeconds)),
 303       received_close_code_(0),
 304       state_(FRESHLY_CONSTRUCTED),
 305       notification_sender_(new HandshakeNotificationSender(this)),
 306       sending_text_message_(false),
 307       receiving_text_message_(false),
 308       expecting_to_handle_continuation_(false),
 309       initial_frame_forwarded_(false) {}
 310
 311 WebSocketChannel::~WebSocketChannel() {
 312   // The stream may hold a pointer to read_frames_, and so it needs to be
 313   // destroyed first.
 314   stream_.reset();
 315   // The timer may have a callback pointing back to us, so stop it just in case
 316   // someone decides to run the event loop from their destructor.
 317   timer_.Stop();
 318 }
 319
 320 void WebSocketChannel::SendAddChannelRequest(
 321     const GURL& socket_url,
 322     const std::vector<std::string>& requested_subprotocols,
 323     const url::Origin& origin) {
 324   // Delegate to the tested version.
 325   SendAddChannelRequestWithSuppliedCreator(
 326       socket_url,
 327       requested_subprotocols,
 328       origin,
 329       base::Bind(&WebSocketStream::CreateAndConnectStream));
 330 }
 331
 332 void WebSocketChannel::SetState(State new_state) {
 333   DCHECK_NE(state_, new_state);
 334
 335   if (new_state == CONNECTED)
 336     established_on_ = base::TimeTicks::Now();
 337   if (state_ == CONNECTED && !established_on_.is_null()) {
 338     UMA_HISTOGRAM_LONG_TIMES(
 339         "Net.WebSocket.Duration", base::TimeTicks::Now() - established_on_);
 340   }
 341
 342   state_ = new_state;
 343 }
 344
 345 bool WebSocketChannel::InClosingState() const {
 346   // The state RECV_CLOSED is not supported here, because it is only used in one
 347   // code path and should not leak into the code in general.
 348   DCHECK_NE(RECV_CLOSED, state_)
 349       << "InClosingState called with state_ == RECV_CLOSED";
 350   return state_ == SEND_CLOSED || state_ == CLOSE_WAIT || state_ == CLOSED;
 351 }
 352
 353 void WebSocketChannel::SendFrame(bool fin,
 354                                  WebSocketFrameHeader::OpCode op_code,
 355                                  const std::vector<char>& data) {
 356   if (data.size() > INT_MAX) {
 357     NOTREACHED() << "Frame size sanity check failed";
 358     return;
 359   }
 360   if (stream_ == NULL) {
 361     LOG(DFATAL) << "Got SendFrame without a connection established; "
 362                 << "misbehaving renderer? fin=" << fin << " op_code=" << op_code
 363                 << " data.size()=" << data.size();
 364     return;
 365   }
 366   if (InClosingState()) {
 367     DVLOG(1) << "SendFrame called in state " << state_
 368              << ". This may be a bug, or a harmless race.";
 369     return;
 370   }
 371   if (state_ != CONNECTED) {
 372     NOTREACHED() << "SendFrame() called in state " << state_;
 373     return;
 374   }
 375   if (data.size() > base::checked_cast<size_t>(current_send_quota_)) {
 376     // TODO(ricea): Kill renderer.
 377     AllowUnused(
 378         FailChannel("Send quota exceeded", kWebSocketErrorGoingAway, ""));
 379     // |this| has been deleted.
 380     return;
 381   }
 382   if (!WebSocketFrameHeader::IsKnownDataOpCode(op_code)) {
 383     LOG(DFATAL) << "Got SendFrame with bogus op_code " << op_code
 384                 << "; misbehaving renderer? fin=" << fin
 385                 << " data.size()=" << data.size();
 386     return;
 387   }
 388   if (op_code == WebSocketFrameHeader::kOpCodeText ||
 389       (op_code == WebSocketFrameHeader::kOpCodeContinuation &&
 390        sending_text_message_)) {
 391     StreamingUtf8Validator::State state =
 392         outgoing_utf8_validator_.AddBytes(vector_as_array(&data), data.size());
 393     if (state == StreamingUtf8Validator::INVALID ||
 394         (state == StreamingUtf8Validator::VALID_MIDPOINT && fin)) {
 395       // TODO(ricea): Kill renderer.
 396       AllowUnused(
 397           FailChannel("Browser sent a text frame containing invalid UTF-8",
 398                       kWebSocketErrorGoingAway,
 399                       ""));
 400       // |this| has been deleted.
 401       return;
 402     }
 403     sending_text_message_ = !fin;
 404     DCHECK(!fin || state == StreamingUtf8Validator::VALID_ENDPOINT);
 405   }
 406   current_send_quota_ -= data.size();
 407   // TODO(ricea): If current_send_quota_ has dropped below
 408   // send_quota_low_water_mark_, it might be good to increase the "low
 409   // water mark" and "high water mark", but only if the link to the WebSocket
 410   // server is not saturated.
 411   scoped_refptr<IOBuffer> buffer(new IOBuffer(data.size()));
 412   std::copy(data.begin(), data.end(), buffer->data());
 413   AllowUnused(SendFrameFromIOBuffer(fin, op_code, buffer, data.size()));
 414   // |this| may have been deleted.
 415 }
 416
 417 void WebSocketChannel::SendFlowControl(int64 quota) {
 418   DCHECK(state_ == CONNECTING || state_ == CONNECTED || state_ == SEND_CLOSED ||
 419          state_ == CLOSE_WAIT);
 420   // TODO(ricea): Kill the renderer if it tries to send us a negative quota
 421   // value or > INT_MAX.
 422   DCHECK_GE(quota, 0);
 423   DCHECK_LE(quota, INT_MAX);
 424   if (!pending_received_frames_.empty()) {
 425     DCHECK_EQ(0, current_receive_quota_);
 426   }
 427   while (!pending_received_frames_.empty() && quota > 0) {
 428     PendingReceivedFrame& front = pending_received_frames_.front();
 429     const size_t data_size = front.size() - front.offset();
 430     const size_t bytes_to_send =
 431         std::min(base::checked_cast<size_t>(quota), data_size);
 432     const bool final = front.final() && data_size == bytes_to_send;
 433     const char* data = front.data() ?
 434         front.data()->data() + front.offset() : NULL;
 435     DCHECK(!bytes_to_send || data) << "Non empty data should not be null.";
 436     const std::vector<char> data_vector(data, data + bytes_to_send);
 437     DVLOG(3) << "Sending frame previously split due to quota to the "
 438              << "renderer: quota=" << quota << " data_size=" << data_size
 439              << " bytes_to_send=" << bytes_to_send;
 440     if (event_interface_->OnDataFrame(final, front.opcode(), data_vector) ==
 441         CHANNEL_DELETED)
 442       return;
 443     if (bytes_to_send < data_size) {
 444       front.DidConsume(bytes_to_send);
 445       front.ResetOpcode();
 446       return;
 447     }
 448     const int64 signed_bytes_to_send = base::checked_cast<int64>(bytes_to_send);
 449     DCHECK_GE(quota, signed_bytes_to_send);
 450     quota -= signed_bytes_to_send;
 451
 452     pending_received_frames_.pop();
 453   }
 454   // If current_receive_quota_ == 0 then there is no pending ReadFrames()
 455   // operation.
 456   const bool start_read =
 457       current_receive_quota_ == 0 && quota > 0 &&
 458       (state_ == CONNECTED || state_ == SEND_CLOSED || state_ == CLOSE_WAIT);
 459   current_receive_quota_ += base::checked_cast<int>(quota);
 460   if (start_read)
 461     AllowUnused(ReadFrames());
 462   // |this| may have been deleted.
 463 }
 464
 465 void WebSocketChannel::StartClosingHandshake(uint16 code,
 466                                              const std::string& reason) {
 467   if (InClosingState()) {
 468     DVLOG(1) << "StartClosingHandshake called in state " << state_
 469              << ". This may be a bug, or a harmless race.";
 470     return;
 471   }
 472   if (state_ == CONNECTING) {
 473     // Abort the in-progress handshake and drop the connection immediately.
 474     stream_request_.reset();
 475     SetState(CLOSED);
 476     AllowUnused(DoDropChannel(false, kWebSocketErrorAbnormalClosure, ""));
 477     return;
 478   }
 479   if (state_ != CONNECTED) {
 480     NOTREACHED() << "StartClosingHandshake() called in state " << state_;
 481     return;
 482   }
 483   // Javascript actually only permits 1000 and 3000-4999, but the implementation
 484   // itself may produce different codes. The length of |reason| is also checked
 485   // by Javascript.
 486   if (!IsStrictlyValidCloseStatusCode(code) ||
 487       reason.size() > kMaximumCloseReasonLength) {
 488     // "InternalServerError" is actually used for errors from any endpoint, per
 489     // errata 3227 to RFC6455. If the renderer is sending us an invalid code or
 490     // reason it must be malfunctioning in some way, and based on that we
 491     // interpret this as an internal error.
 492     if (SendClose(kWebSocketErrorInternalServerError, "") != CHANNEL_DELETED) {
 493       DCHECK_EQ(CONNECTED, state_);
 494       SetState(SEND_CLOSED);
 495     }
 496     return;
 497   }
 498   if (SendClose(
 499           code,
 500           StreamingUtf8Validator::Validate(reason) ? reason : std::string()) ==
 501       CHANNEL_DELETED)
 502     return;
 503   DCHECK_EQ(CONNECTED, state_);
 504   SetState(SEND_CLOSED);
 505 }
 506
 507 void WebSocketChannel::SendAddChannelRequestForTesting(
 508     const GURL& socket_url,
 509     const std::vector<std::string>& requested_subprotocols,
 510     const url::Origin& origin,
 511     const WebSocketStreamCreator& creator) {
 512   SendAddChannelRequestWithSuppliedCreator(
 513       socket_url, requested_subprotocols, origin, creator);
 514 }
 515
 516 void WebSocketChannel::SetClosingHandshakeTimeoutForTesting(
 517     base::TimeDelta delay) {
 518   timeout_ = delay;
 519 }
 520
 521 void WebSocketChannel::SendAddChannelRequestWithSuppliedCreator(
 522     const GURL& socket_url,
 523     const std::vector<std::string>& requested_subprotocols,
 524     const url::Origin& origin,
 525     const WebSocketStreamCreator& creator) {
 526   DCHECK_EQ(FRESHLY_CONSTRUCTED, state_);
 527   if (!socket_url.SchemeIsWSOrWSS()) {
 528     // TODO(ricea): Kill the renderer (this error should have been caught by
 529     // Javascript).
 530     AllowUnused(event_interface_->OnAddChannelResponse(true, "", ""));
 531     // |this| is deleted here.
 532     return;
 533   }
 534   socket_url_ = socket_url;
 535   scoped_ptr<WebSocketStream::ConnectDelegate> connect_delegate(
 536       new ConnectDelegate(this));
 537   stream_request_ = creator.Run(socket_url_,
 538                                 requested_subprotocols,
 539                                 origin,
 540                                 url_request_context_,
 541                                 BoundNetLog(),
 542                                 connect_delegate.Pass());
 543   SetState(CONNECTING);
 544 }
 545
 546 void WebSocketChannel::OnConnectSuccess(scoped_ptr<WebSocketStream> stream) {
 547   DCHECK(stream);
 548   DCHECK_EQ(CONNECTING, state_);
 549
 550   stream_ = stream.Pass();
 551
 552   SetState(CONNECTED);
 553
 554   if (event_interface_->OnAddChannelResponse(
 555           false, stream_->GetSubProtocol(), stream_->GetExtensions()) ==
 556       CHANNEL_DELETED)
 557     return;
 558
 559   // TODO(ricea): Get flow control information from the WebSocketStream once we
 560   // have a multiplexing WebSocketStream.
 561   current_send_quota_ = send_quota_high_water_mark_;
 562   if (event_interface_->OnFlowControl(send_quota_high_water_mark_) ==
 563       CHANNEL_DELETED)
 564     return;
 565
 566   // |stream_request_| is not used once the connection has succeeded.
 567   stream_request_.reset();
 568
 569   AllowUnused(ReadFrames());
 570   // |this| may have been deleted.
 571 }
 572
 573 void WebSocketChannel::OnConnectFailure(const std::string& message) {
 574   DCHECK_EQ(CONNECTING, state_);
 575
 576   // Copy the message before we delete its owner.
 577   std::string message_copy = message;
 578
 579   SetState(CLOSED);
 580   stream_request_.reset();
 581
 582   if (CHANNEL_DELETED ==
 583       notification_sender_->SendImmediately(event_interface_.get())) {
 584     // |this| has been deleted.
 585     return;
 586   }
 587   AllowUnused(event_interface_->OnFailChannel(message_copy));
 588   // |this| has been deleted.
 589 }
 590
 591 void WebSocketChannel::OnSSLCertificateError(
 592     scoped_ptr<WebSocketEventInterface::SSLErrorCallbacks> ssl_error_callbacks,
 593     const SSLInfo& ssl_info,
 594     bool fatal) {
 595   AllowUnused(event_interface_->OnSSLCertificateError(
 596       ssl_error_callbacks.Pass(), socket_url_, ssl_info, fatal));
 597 }
 598
 599 void WebSocketChannel::OnStartOpeningHandshake(
 600     scoped_ptr<WebSocketHandshakeRequestInfo> request) {
 601   DCHECK(!notification_sender_->handshake_request_info());
 602
 603   // Because it is hard to handle an IPC error synchronously is difficult,
 604   // we asynchronously notify the information.
 605   notification_sender_->set_handshake_request_info(request.Pass());
 606   ScheduleOpeningHandshakeNotification();
 607 }
 608
 609 void WebSocketChannel::OnFinishOpeningHandshake(
 610     scoped_ptr<WebSocketHandshakeResponseInfo> response) {
 611   DCHECK(!notification_sender_->handshake_response_info());
 612
 613   // Because it is hard to handle an IPC error synchronously is difficult,
 614   // we asynchronously notify the information.
 615   notification_sender_->set_handshake_response_info(response.Pass());
 616   ScheduleOpeningHandshakeNotification();
 617 }
 618
 619 void WebSocketChannel::ScheduleOpeningHandshakeNotification() {
 620   base::MessageLoop::current()->PostTask(
 621       FROM_HERE,
 622       base::Bind(HandshakeNotificationSender::Send,
 623                  notification_sender_->AsWeakPtr()));
 624 }
 625
 626 ChannelState WebSocketChannel::WriteFrames() {
 627   int result = OK;
 628   do {
 629     // This use of base::Unretained is safe because this object owns the
 630     // WebSocketStream and destroying it cancels all callbacks.
 631     result = stream_->WriteFrames(
 632         data_being_sent_->frames(),
 633         base::Bind(base::IgnoreResult(&WebSocketChannel::OnWriteDone),
 634                    base::Unretained(this),
 635                    false));
 636     if (result != ERR_IO_PENDING) {
 637       if (OnWriteDone(true, result) == CHANNEL_DELETED)
 638         return CHANNEL_DELETED;
 639       // OnWriteDone() returns CHANNEL_DELETED on error. Here |state_| is
 640       // guaranteed to be the same as before OnWriteDone() call.
 641     }
 642   } while (result == OK && data_being_sent_);
 643   return CHANNEL_ALIVE;
 644 }
 645
 646 ChannelState WebSocketChannel::OnWriteDone(bool synchronous, int result) {
 647   DCHECK_NE(FRESHLY_CONSTRUCTED, state_);
 648   DCHECK_NE(CONNECTING, state_);
 649   DCHECK_NE(ERR_IO_PENDING, result);
 650   DCHECK(data_being_sent_);
 651   switch (result) {
 652     case OK:
 653       if (data_to_send_next_) {
 654         data_being_sent_ = data_to_send_next_.Pass();
 655         if (!synchronous)
 656           return WriteFrames();
 657       } else {
 658         data_being_sent_.reset();
 659         if (current_send_quota_ < send_quota_low_water_mark_) {
 660           // TODO(ricea): Increase low_water_mark and high_water_mark if
 661           // throughput is high, reduce them if throughput is low.  Low water
 662           // mark needs to be >= the bandwidth delay product *of the IPC
 663           // channel*. Because factors like context-switch time, thread wake-up
 664           // time, and bus speed come into play it is complex and probably needs
 665           // to be determined empirically.
 666           DCHECK_LE(send_quota_low_water_mark_, send_quota_high_water_mark_);
 667           // TODO(ricea): Truncate quota by the quota specified by the remote
 668           // server, if the protocol in use supports quota.
 669           int fresh_quota = send_quota_high_water_mark_ - current_send_quota_;
 670           current_send_quota_ += fresh_quota;
 671           return event_interface_->OnFlowControl(fresh_quota);
 672         }
 673       }
 674       return CHANNEL_ALIVE;
 675
 676     // If a recoverable error condition existed, it would go here.
 677
 678     default:
 679       DCHECK_LT(result, 0)
 680           << "WriteFrames() should only return OK or ERR_ codes";
 681
 682       stream_->Close();
 683       SetState(CLOSED);
 684       return DoDropChannel(false, kWebSocketErrorAbnormalClosure, "");
 685   }
 686 }
 687
 688 ChannelState WebSocketChannel::ReadFrames() {
 689   int result = OK;
 690   while (result == OK && current_receive_quota_ > 0) {
 691     // This use of base::Unretained is safe because this object owns the
 692     // WebSocketStream, and any pending reads will be cancelled when it is
 693     // destroyed.
 694     result = stream_->ReadFrames(
 695         &read_frames_,
 696         base::Bind(base::IgnoreResult(&WebSocketChannel::OnReadDone),
 697                    base::Unretained(this),
 698                    false));
 699     if (result != ERR_IO_PENDING) {
 700       if (OnReadDone(true, result) == CHANNEL_DELETED)
 701         return CHANNEL_DELETED;
 702     }
 703     DCHECK_NE(CLOSED, state_);
 704   }
 705   return CHANNEL_ALIVE;
 706 }
 707
 708 ChannelState WebSocketChannel::OnReadDone(bool synchronous, int result) {
 709   DCHECK_NE(FRESHLY_CONSTRUCTED, state_);
 710   DCHECK_NE(CONNECTING, state_);
 711   DCHECK_NE(ERR_IO_PENDING, result);
 712   switch (result) {
 713     case OK:
 714       // ReadFrames() must use ERR_CONNECTION_CLOSED for a closed connection
 715       // with no data read, not an empty response.
 716       DCHECK(!read_frames_.empty())
 717           << "ReadFrames() returned OK, but nothing was read.";
 718       for (size_t i = 0; i < read_frames_.size(); ++i) {
 719         scoped_ptr<WebSocketFrame> frame(read_frames_[i]);
 720         read_frames_[i] = NULL;
 721         if (HandleFrame(frame.Pass()) == CHANNEL_DELETED)
 722           return CHANNEL_DELETED;
 723       }
 724       read_frames_.clear();
 725       // There should always be a call to ReadFrames pending.
 726       // TODO(ricea): Unless we are out of quota.
 727       DCHECK_NE(CLOSED, state_);
 728       if (!synchronous)
 729         return ReadFrames();
 730       return CHANNEL_ALIVE;
 731
 732     case ERR_WS_PROTOCOL_ERROR:
 733       // This could be kWebSocketErrorProtocolError (specifically, non-minimal
 734       // encoding of payload length) or kWebSocketErrorMessageTooBig, or an
 735       // extension-specific error.
 736       return FailChannel("Invalid frame header",
 737                          kWebSocketErrorProtocolError,
 738                          "WebSocket Protocol Error");
 739
 740     default:
 741       DCHECK_LT(result, 0)
 742           << "ReadFrames() should only return OK or ERR_ codes";
 743
 744       stream_->Close();
 745       SetState(CLOSED);
 746
 747       uint16 code = kWebSocketErrorAbnormalClosure;
 748       std::string reason = "";
 749       bool was_clean = false;
 750       if (received_close_code_ != 0) {
 751         code = received_close_code_;
 752         reason = received_close_reason_;
 753         was_clean = (result == ERR_CONNECTION_CLOSED);
 754       }
 755
 756       return DoDropChannel(was_clean, code, reason);
 757   }
 758 }
 759
 760 ChannelState WebSocketChannel::HandleFrame(scoped_ptr<WebSocketFrame> frame) {
 761   if (frame->header.masked) {
 762     // RFC6455 Section 5.1 "A client MUST close a connection if it detects a
 763     // masked frame."
 764     return FailChannel(
 765         "A server must not mask any frames that it sends to the "
 766         "client.",
 767         kWebSocketErrorProtocolError,
 768         "Masked frame from server");
 769   }
 770   const WebSocketFrameHeader::OpCode opcode = frame->header.opcode;
 771   DCHECK(!WebSocketFrameHeader::IsKnownControlOpCode(opcode) ||
 772          frame->header.final);
 773   if (frame->header.reserved1 || frame->header.reserved2 ||
 774       frame->header.reserved3) {
 775     return FailChannel(base::StringPrintf(
 776                            "One or more reserved bits are on: reserved1 = %d, "
 777                            "reserved2 = %d, reserved3 = %d",
 778                            static_cast<int>(frame->header.reserved1),
 779                            static_cast<int>(frame->header.reserved2),
 780                            static_cast<int>(frame->header.reserved3)),
 781                        kWebSocketErrorProtocolError,
 782                        "Invalid reserved bit");
 783   }
 784
 785   // Respond to the frame appropriately to its type.
 786   return HandleFrameByState(
 787       opcode, frame->header.final, frame->data, frame->header.payload_length);
 788 }
 789
 790 ChannelState WebSocketChannel::HandleFrameByState(
 791     const WebSocketFrameHeader::OpCode opcode,
 792     bool final,
 793     const scoped_refptr<IOBuffer>& data_buffer,
 794     size_t size) {
 795   DCHECK_NE(RECV_CLOSED, state_)
 796       << "HandleFrame() does not support being called re-entrantly from within "
 797          "SendClose()";
 798   DCHECK_NE(CLOSED, state_);
 799   if (state_ == CLOSE_WAIT) {
 800     std::string frame_name;
 801     GetFrameTypeForOpcode(opcode, &frame_name);
 802
 803     // FailChannel() won't send another Close frame.
 804     return FailChannel(
 805         frame_name + " received after close", kWebSocketErrorProtocolError, "");
 806   }
 807   switch (opcode) {
 808     case WebSocketFrameHeader::kOpCodeText:  // fall-thru
 809     case WebSocketFrameHeader::kOpCodeBinary:
 810     case WebSocketFrameHeader::kOpCodeContinuation:
 811       return HandleDataFrame(opcode, final, data_buffer, size);
 812
 813     case WebSocketFrameHeader::kOpCodePing:
 814       DVLOG(1) << "Got Ping of size " << size;
 815       if (state_ == CONNECTED)
 816         return SendFrameFromIOBuffer(
 817             true, WebSocketFrameHeader::kOpCodePong, data_buffer, size);
 818       DVLOG(3) << "Ignored ping in state " << state_;
 819       return CHANNEL_ALIVE;
 820
 821     case WebSocketFrameHeader::kOpCodePong:
 822       DVLOG(1) << "Got Pong of size " << size;
 823       // There is no need to do anything with pong messages.
 824       return CHANNEL_ALIVE;
 825
 826     case WebSocketFrameHeader::kOpCodeClose: {
 827       // TODO(ricea): If there is a message which is queued for transmission to
 828       // the renderer, then the renderer should not receive an
 829       // OnClosingHandshake or OnDropChannel IPC until the queued message has
 830       // been completedly transmitted.
 831       uint16 code = kWebSocketNormalClosure;
 832       std::string reason;
 833       std::string message;
 834       if (!ParseClose(data_buffer, size, &code, &reason, &message)) {
 835         return FailChannel(message, code, reason);
 836       }
 837       // TODO(ricea): Find a way to safely log the message from the close
 838       // message (escape control codes and so on).
 839       DVLOG(1) << "Got Close with code " << code;
 840       switch (state_) {
 841         case CONNECTED:
 842           SetState(RECV_CLOSED);
 843           if (SendClose(code, reason) == CHANNEL_DELETED)
 844             return CHANNEL_DELETED;
 845           DCHECK_EQ(RECV_CLOSED, state_);
 846           SetState(CLOSE_WAIT);
 847
 848           if (event_interface_->OnClosingHandshake() == CHANNEL_DELETED)
 849             return CHANNEL_DELETED;
 850           received_close_code_ = code;
 851           received_close_reason_ = reason;
 852           break;
 853
 854         case SEND_CLOSED:
 855           SetState(CLOSE_WAIT);
 856           // From RFC6455 section 7.1.5: "Each endpoint
 857           // will see the status code sent by the other end as _The WebSocket
 858           // Connection Close Code_."
 859           received_close_code_ = code;
 860           received_close_reason_ = reason;
 861           break;
 862
 863         default:
 864           LOG(DFATAL) << "Got Close in unexpected state " << state_;
 865           break;
 866       }
 867       return CHANNEL_ALIVE;
 868     }
 869
 870     default:
 871       return FailChannel(
 872           base::StringPrintf("Unrecognized frame opcode: %d", opcode),
 873           kWebSocketErrorProtocolError,
 874           "Unknown opcode");
 875   }
 876 }
 877
 878 ChannelState WebSocketChannel::HandleDataFrame(
 879     WebSocketFrameHeader::OpCode opcode,
 880     bool final,
 881     const scoped_refptr<IOBuffer>& data_buffer,
 882     size_t size) {
 883   if (state_ != CONNECTED) {
 884     DVLOG(3) << "Ignored data packet received in state " << state_;
 885     return CHANNEL_ALIVE;
 886   }
 887   DCHECK(opcode == WebSocketFrameHeader::kOpCodeContinuation ||
 888          opcode == WebSocketFrameHeader::kOpCodeText ||
 889          opcode == WebSocketFrameHeader::kOpCodeBinary);
 890   const bool got_continuation =
 891       (opcode == WebSocketFrameHeader::kOpCodeContinuation);
 892   if (got_continuation != expecting_to_handle_continuation_) {
 893     const std::string console_log = got_continuation
 894         ? "Received unexpected continuation frame."
 895         : "Received start of new message but previous message is unfinished.";
 896     const std::string reason = got_continuation
 897         ? "Unexpected continuation"
 898         : "Previous data frame unfinished";
 899     return FailChannel(console_log, kWebSocketErrorProtocolError, reason);
 900   }
 901   expecting_to_handle_continuation_ = !final;
 902   WebSocketFrameHeader::OpCode opcode_to_send = opcode;
 903   if (!initial_frame_forwarded_ &&
 904       opcode == WebSocketFrameHeader::kOpCodeContinuation) {
 905     opcode_to_send = receiving_text_message_
 906                          ? WebSocketFrameHeader::kOpCodeText
 907                          : WebSocketFrameHeader::kOpCodeBinary;
 908   }
 909   if (opcode == WebSocketFrameHeader::kOpCodeText ||
 910       (opcode == WebSocketFrameHeader::kOpCodeContinuation &&
 911        receiving_text_message_)) {
 912     // This call is not redundant when size == 0 because it tells us what
 913     // the current state is.
 914     StreamingUtf8Validator::State state = incoming_utf8_validator_.AddBytes(
 915         size ? data_buffer->data() : NULL, size);
 916     if (state == StreamingUtf8Validator::INVALID ||
 917         (state == StreamingUtf8Validator::VALID_MIDPOINT && final)) {
 918       return FailChannel("Could not decode a text frame as UTF-8.",
 919                          kWebSocketErrorProtocolError,
 920                          "Invalid UTF-8 in text frame");
 921     }
 922     receiving_text_message_ = !final;
 923     DCHECK(!final || state == StreamingUtf8Validator::VALID_ENDPOINT);
 924   }
 925   if (size == 0U && !final)
 926     return CHANNEL_ALIVE;
 927
 928   initial_frame_forwarded_ = !final;
 929   if (size > base::checked_cast<size_t>(current_receive_quota_) ||
 930       !pending_received_frames_.empty()) {
 931     const bool no_quota = (current_receive_quota_ == 0);
 932     DCHECK(no_quota || pending_received_frames_.empty());
 933     DVLOG(3) << "Queueing frame to renderer due to quota. quota="
 934              << current_receive_quota_ << " size=" << size;
 935     WebSocketFrameHeader::OpCode opcode_to_queue =
 936         no_quota ? opcode_to_send : WebSocketFrameHeader::kOpCodeContinuation;
 937     pending_received_frames_.push(PendingReceivedFrame(
 938         final, opcode_to_queue, data_buffer, current_receive_quota_, size));
 939     if (no_quota)
 940       return CHANNEL_ALIVE;
 941     size = current_receive_quota_;
 942     final = false;
 943   }
 944
 945   // TODO(ricea): Can this copy be eliminated?
 946   const char* const data_begin = size ? data_buffer->data() : NULL;
 947   const char* const data_end = data_begin + size;
 948   const std::vector<char> data(data_begin, data_end);
 949   current_receive_quota_ -= size;
 950   DCHECK_GE(current_receive_quota_, 0);
 951
 952   // Sends the received frame to the renderer process.
 953   return event_interface_->OnDataFrame(final, opcode_to_send, data);
 954 }
 955
 956 ChannelState WebSocketChannel::SendFrameFromIOBuffer(
 957     bool fin,
 958     WebSocketFrameHeader::OpCode op_code,
 959     const scoped_refptr<IOBuffer>& buffer,
 960     size_t size) {
 961   DCHECK(state_ == CONNECTED || state_ == RECV_CLOSED);
 962   DCHECK(stream_);
 963
 964   scoped_ptr<WebSocketFrame> frame(new WebSocketFrame(op_code));
 965   WebSocketFrameHeader& header = frame->header;
 966   header.final = fin;
 967   header.masked = true;
 968   header.payload_length = size;
 969   frame->data = buffer;
 970
 971   if (data_being_sent_) {
 972     // Either the link to the WebSocket server is saturated, or several messages
 973     // are being sent in a batch.
 974     // TODO(ricea): Keep some statistics to work out the situation and adjust
 975     // quota appropriately.
 976     if (!data_to_send_next_)
 977       data_to_send_next_.reset(new SendBuffer);
 978     data_to_send_next_->AddFrame(frame.Pass());
 979     return CHANNEL_ALIVE;
 980   }
 981
 982   data_being_sent_.reset(new SendBuffer);
 983   data_being_sent_->AddFrame(frame.Pass());
 984   return WriteFrames();
 985 }
 986
 987 ChannelState WebSocketChannel::FailChannel(const std::string& message,
 988                                            uint16 code,
 989                                            const std::string& reason) {
 990   DCHECK_NE(FRESHLY_CONSTRUCTED, state_);
 991   DCHECK_NE(CONNECTING, state_);
 992   DCHECK_NE(CLOSED, state_);
 993
 994   // TODO(ricea): Logging.
 995   if (state_ == CONNECTED) {
 996     if (SendClose(code, reason) == CHANNEL_DELETED)
 997       return CHANNEL_DELETED;
 998   }
 999
1000   // Careful study of RFC6455 section 7.1.7 and 7.1.1 indicates the browser
1001   // should close the connection itself without waiting for the closing
1002   // handshake.
1003   stream_->Close();
1004   SetState(CLOSED);
1005   return event_interface_->OnFailChannel(message);
1006 }
1007
1008 ChannelState WebSocketChannel::SendClose(uint16 code,
1009                                          const std::string& reason) {
1010   DCHECK(state_ == CONNECTED || state_ == RECV_CLOSED);
1011   DCHECK_LE(reason.size(), kMaximumCloseReasonLength);
1012   scoped_refptr<IOBuffer> body;
1013   size_t size = 0;
1014   if (code == kWebSocketErrorNoStatusReceived) {
1015     // Special case: translate kWebSocketErrorNoStatusReceived into a Close
1016     // frame with no payload.
1017     DCHECK(reason.empty());
1018     body = new IOBuffer(0);
1019   } else {
1020     const size_t payload_length = kWebSocketCloseCodeLength + reason.length();
1021     body = new IOBuffer(payload_length);
1022     size = payload_length;
1023     base::WriteBigEndian(body->data(), code);
1024     COMPILE_ASSERT(sizeof(code) == kWebSocketCloseCodeLength,
1025                    they_should_both_be_two);
1026     std::copy(
1027         reason.begin(), reason.end(), body->data() + kWebSocketCloseCodeLength);
1028   }
1029   // This use of base::Unretained() is safe because we stop the timer in the
1030   // destructor.
1031   timer_.Start(
1032       FROM_HERE,
1033       timeout_,
1034       base::Bind(&WebSocketChannel::CloseTimeout, base::Unretained(this)));
1035   if (SendFrameFromIOBuffer(
1036           true, WebSocketFrameHeader::kOpCodeClose, body, size) ==
1037       CHANNEL_DELETED)
1038     return CHANNEL_DELETED;
1039   return CHANNEL_ALIVE;
1040 }
1041
1042 bool WebSocketChannel::ParseClose(const scoped_refptr<IOBuffer>& buffer,
1043                                   size_t size,
1044                                   uint16* code,
1045                                   std::string* reason,
1046                                   std::string* message) {
1047   reason->clear();
1048   if (size < kWebSocketCloseCodeLength) {
1049     if (size == 0U) {
1050       *code = kWebSocketErrorNoStatusReceived;
1051       return true;
1052     }
1053
1054     DVLOG(1) << "Close frame with payload size " << size << " received "
1055              << "(the first byte is " << std::hex
1056              << static_cast<int>(buffer->data()[0]) << ")";
1057     *code = kWebSocketErrorProtocolError;
1058     *message =
1059         "Received a broken close frame containing an invalid size body.";
1060     return false;
1061   }
1062
1063   const char* data = buffer->data();
1064   uint16 unchecked_code = 0;
1065   base::ReadBigEndian(data, &unchecked_code);
1066   COMPILE_ASSERT(sizeof(unchecked_code) == kWebSocketCloseCodeLength,
1067                  they_should_both_be_two_bytes);
1068
1069   switch (unchecked_code) {
1070     case kWebSocketErrorNoStatusReceived:
1071     case kWebSocketErrorAbnormalClosure:
1072     case kWebSocketErrorTlsHandshake:
1073       *code = kWebSocketErrorProtocolError;
1074       *message =
1075           "Received a broken close frame containing a reserved status code.";
1076       return false;
1077
1078     default:
1079       *code = unchecked_code;
1080       break;
1081   }
1082
1083   std::string text(data + kWebSocketCloseCodeLength, data + size);
1084   if (StreamingUtf8Validator::Validate(text)) {
1085     reason->swap(text);
1086     return true;
1087   }
1088
1089   *code = kWebSocketErrorProtocolError;
1090   *reason = "Invalid UTF-8 in Close frame";
1091   *message = "Received a broken close frame containing invalid UTF-8.";
1092   return false;
1093 }
1094
1095 ChannelState WebSocketChannel::DoDropChannel(bool was_clean,
1096                                              uint16 code,
1097                                              const std::string& reason) {
1098   if (CHANNEL_DELETED ==
1099       notification_sender_->SendImmediately(event_interface_.get()))
1100     return CHANNEL_DELETED;
1101   ChannelState result =
1102       event_interface_->OnDropChannel(was_clean, code, reason);
1103   DCHECK_EQ(CHANNEL_DELETED, result);
1104   return result;
1105 }
1106
1107 void WebSocketChannel::CloseTimeout() {
1108   stream_->Close();
1109   SetState(CLOSED);
1110   AllowUnused(DoDropChannel(false, kWebSocketErrorAbnormalClosure, ""));
1111   // |this| has been deleted.
1112 }
1113
1114 }  // namespace net