1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
|
// 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.
#include "net/quic/reliable_quic_stream.h"
#include "base/logging.h"
#include "net/quic/iovector.h"
#include "net/quic/quic_bug_tracker.h"
#include "net/quic/quic_flags.h"
#include "net/quic/quic_flow_controller.h"
#include "net/quic/quic_session.h"
#include "net/quic/quic_write_blocked_list.h"
using base::StringPiece;
using std::min;
using std::string;
namespace net {
#define ENDPOINT \
(perspective_ == Perspective::IS_SERVER ? "Server: " : "Client: ")
namespace {
struct iovec MakeIovec(StringPiece data) {
struct iovec iov = {const_cast<char*>(data.data()),
static_cast<size_t>(data.size())};
return iov;
}
size_t GetInitialStreamFlowControlWindowToSend(QuicSession* session) {
return session->config()->GetInitialStreamFlowControlWindowToSend();
}
size_t GetReceivedFlowControlWindow(QuicSession* session) {
if (session->config()->HasReceivedInitialStreamFlowControlWindowBytes()) {
return session->config()->ReceivedInitialStreamFlowControlWindowBytes();
}
return kMinimumFlowControlSendWindow;
}
} // namespace
ReliableQuicStream::PendingData::PendingData(
string data_in,
QuicAckListenerInterface* ack_listener_in)
: data(data_in), offset(0), ack_listener(ack_listener_in) {}
ReliableQuicStream::PendingData::~PendingData() {}
ReliableQuicStream::ReliableQuicStream(QuicStreamId id, QuicSession* session)
: queued_data_bytes_(0),
sequencer_(this, session->connection()->clock()),
id_(id),
session_(session),
stream_bytes_read_(0),
stream_bytes_written_(0),
stream_error_(QUIC_STREAM_NO_ERROR),
connection_error_(QUIC_NO_ERROR),
read_side_closed_(false),
write_side_closed_(false),
fin_buffered_(false),
fin_sent_(false),
fin_received_(false),
rst_sent_(false),
rst_received_(false),
perspective_(session_->perspective()),
flow_controller_(session_->connection(),
id_,
perspective_,
GetReceivedFlowControlWindow(session),
GetInitialStreamFlowControlWindowToSend(session),
session_->flow_controller()->auto_tune_receive_window()),
connection_flow_controller_(session_->flow_controller()),
stream_contributes_to_connection_flow_control_(true) {
SetFromConfig();
}
ReliableQuicStream::~ReliableQuicStream() {}
void ReliableQuicStream::SetFromConfig() {}
void ReliableQuicStream::OnStreamFrame(const QuicStreamFrame& frame) {
DCHECK_EQ(frame.stream_id, id_);
DCHECK(!(read_side_closed_ && write_side_closed_));
if (frame.fin) {
fin_received_ = true;
if (fin_sent_) {
session_->StreamDraining(id_);
}
}
if (read_side_closed_) {
DVLOG(1) << ENDPOINT << "Ignoring data in frame " << frame.stream_id;
// The subclass does not want to read data: blackhole the data.
return;
}
// This count includes duplicate data received.
size_t frame_payload_size = frame.frame_length;
stream_bytes_read_ += frame_payload_size;
// Flow control is interested in tracking highest received offset.
if (MaybeIncreaseHighestReceivedOffset(frame.offset + frame_payload_size)) {
// As the highest received offset has changed, check to see if this is a
// violation of flow control.
if (flow_controller_.FlowControlViolation() ||
connection_flow_controller_->FlowControlViolation()) {
session_->connection()->SendConnectionCloseWithDetails(
QUIC_FLOW_CONTROL_RECEIVED_TOO_MUCH_DATA,
"Flow control violation after increasing offset");
return;
}
}
sequencer_.OnStreamFrame(frame);
}
int ReliableQuicStream::num_frames_received() const {
return sequencer_.num_frames_received();
}
int ReliableQuicStream::num_early_frames_received() const {
return sequencer_.num_early_frames_received();
}
int ReliableQuicStream::num_duplicate_frames_received() const {
return sequencer_.num_duplicate_frames_received();
}
void ReliableQuicStream::OnStreamReset(const QuicRstStreamFrame& frame) {
rst_received_ = true;
MaybeIncreaseHighestReceivedOffset(frame.byte_offset);
stream_error_ = frame.error_code;
CloseWriteSide();
CloseReadSide();
}
void ReliableQuicStream::OnConnectionClosed(QuicErrorCode error,
ConnectionCloseSource /*source*/) {
if (read_side_closed_ && write_side_closed_) {
return;
}
if (error != QUIC_NO_ERROR) {
stream_error_ = QUIC_STREAM_CONNECTION_ERROR;
connection_error_ = error;
}
CloseWriteSide();
CloseReadSide();
}
void ReliableQuicStream::OnFinRead() {
DCHECK(sequencer_.IsClosed());
// OnFinRead can be called due to a FIN flag in a headers block, so there may
// have been no OnStreamFrame call with a FIN in the frame.
fin_received_ = true;
// If fin_sent_ is true, then CloseWriteSide has already been called, and the
// stream will be destroyed by CloseReadSide, so don't need to call
// StreamDraining.
CloseReadSide();
}
void ReliableQuicStream::Reset(QuicRstStreamErrorCode error) {
stream_error_ = error;
// Sending a RstStream results in calling CloseStream.
session()->SendRstStream(id(), error, stream_bytes_written_);
rst_sent_ = true;
}
void ReliableQuicStream::CloseConnectionWithDetails(QuicErrorCode error,
const string& details) {
session()->connection()->SendConnectionCloseWithDetails(error, details);
}
void ReliableQuicStream::WriteOrBufferData(
StringPiece data,
bool fin,
QuicAckListenerInterface* ack_listener) {
if (data.empty() && !fin) {
QUIC_BUG << "data.empty() && !fin";
return;
}
if (fin_buffered_) {
QUIC_BUG << "Fin already buffered";
return;
}
if (write_side_closed_) {
DLOG(ERROR) << ENDPOINT << "Attempt to write when the write side is closed";
return;
}
QuicConsumedData consumed_data(0, false);
fin_buffered_ = fin;
if (queued_data_.empty()) {
struct iovec iov(MakeIovec(data));
consumed_data = WritevData(&iov, 1, fin, ack_listener);
DCHECK_LE(consumed_data.bytes_consumed, data.length());
}
// If there's unconsumed data or an unconsumed fin, queue it.
if (consumed_data.bytes_consumed < data.length() ||
(fin && !consumed_data.fin_consumed)) {
StringPiece remainder(data.substr(consumed_data.bytes_consumed));
queued_data_bytes_ += remainder.size();
queued_data_.emplace_back(remainder.as_string(), ack_listener);
}
}
void ReliableQuicStream::OnCanWrite() {
bool fin = false;
while (!queued_data_.empty()) {
PendingData* pending_data = &queued_data_.front();
QuicAckListenerInterface* ack_listener = pending_data->ack_listener.get();
if (queued_data_.size() == 1 && fin_buffered_) {
fin = true;
}
if (pending_data->offset > 0 &&
pending_data->offset >= pending_data->data.size()) {
// This should be impossible because offset tracks the amount of
// pending_data written thus far.
QUIC_BUG << "Pending offset is beyond available data. offset: "
<< pending_data->offset << " vs: " << pending_data->data.size();
return;
}
size_t remaining_len = pending_data->data.size() - pending_data->offset;
struct iovec iov = {
const_cast<char*>(pending_data->data.data()) + pending_data->offset,
remaining_len};
QuicConsumedData consumed_data = WritevData(&iov, 1, fin, ack_listener);
queued_data_bytes_ -= consumed_data.bytes_consumed;
if (consumed_data.bytes_consumed == remaining_len &&
fin == consumed_data.fin_consumed) {
queued_data_.pop_front();
} else {
if (consumed_data.bytes_consumed > 0) {
pending_data->offset += consumed_data.bytes_consumed;
}
break;
}
}
}
void ReliableQuicStream::MaybeSendBlocked() {
flow_controller_.MaybeSendBlocked();
if (!stream_contributes_to_connection_flow_control_) {
return;
}
connection_flow_controller_->MaybeSendBlocked();
// If the stream is blocked by connection-level flow control but not by
// stream-level flow control, add the stream to the write blocked list so that
// the stream will be given a chance to write when a connection-level
// WINDOW_UPDATE arrives.
if (connection_flow_controller_->IsBlocked() &&
!flow_controller_.IsBlocked()) {
session_->MarkConnectionLevelWriteBlocked(id());
}
}
QuicConsumedData ReliableQuicStream::WritevData(
const struct iovec* iov,
int iov_count,
bool fin,
QuicAckListenerInterface* ack_listener) {
if (write_side_closed_) {
DLOG(ERROR) << ENDPOINT << "Attempt to write when the write side is closed";
return QuicConsumedData(0, false);
}
// How much data was provided.
size_t write_length = TotalIovecLength(iov, iov_count);
// A FIN with zero data payload should not be flow control blocked.
bool fin_with_zero_data = (fin && write_length == 0);
// How much data flow control permits to be written.
QuicByteCount send_window = flow_controller_.SendWindowSize();
if (stream_contributes_to_connection_flow_control_) {
send_window =
min(send_window, connection_flow_controller_->SendWindowSize());
}
if (FLAGS_quic_cede_correctly && session_->ShouldYield(id())) {
session_->MarkConnectionLevelWriteBlocked(id());
return QuicConsumedData(0, false);
}
if (send_window == 0 && !fin_with_zero_data) {
// Quick return if nothing can be sent.
MaybeSendBlocked();
return QuicConsumedData(0, false);
}
if (write_length > send_window) {
// Don't send the FIN unless all the data will be sent.
fin = false;
// Writing more data would be a violation of flow control.
write_length = static_cast<size_t>(send_window);
}
QuicConsumedData consumed_data =
session()->WritevData(id(), QuicIOVector(iov, iov_count, write_length),
stream_bytes_written_, fin, ack_listener);
stream_bytes_written_ += consumed_data.bytes_consumed;
AddBytesSent(consumed_data.bytes_consumed);
// The write may have generated a write error causing this stream to be
// closed. If so, simply return without marking the stream write blocked.
if (write_side_closed_) {
return consumed_data;
}
if (consumed_data.bytes_consumed == write_length) {
if (!fin_with_zero_data) {
MaybeSendBlocked();
}
if (fin && consumed_data.fin_consumed) {
fin_sent_ = true;
if (fin_received_) {
session_->StreamDraining(id_);
}
CloseWriteSide();
} else if (fin && !consumed_data.fin_consumed) {
session_->MarkConnectionLevelWriteBlocked(id());
}
} else {
session_->MarkConnectionLevelWriteBlocked(id());
}
return consumed_data;
}
void ReliableQuicStream::CloseReadSide() {
if (read_side_closed_) {
return;
}
DVLOG(1) << ENDPOINT << "Done reading from stream " << id();
read_side_closed_ = true;
if (write_side_closed_) {
DVLOG(1) << ENDPOINT << "Closing stream: " << id();
session_->CloseStream(id());
}
}
void ReliableQuicStream::CloseWriteSide() {
if (write_side_closed_) {
return;
}
DVLOG(1) << ENDPOINT << "Done writing to stream " << id();
write_side_closed_ = true;
if (read_side_closed_) {
DVLOG(1) << ENDPOINT << "Closing stream: " << id();
session_->CloseStream(id());
}
}
bool ReliableQuicStream::HasBufferedData() const {
return !queued_data_.empty();
}
QuicVersion ReliableQuicStream::version() const {
return session_->connection()->version();
}
void ReliableQuicStream::StopReading() {
DVLOG(1) << ENDPOINT << "Stop reading from stream " << id();
sequencer_.StopReading();
}
void ReliableQuicStream::OnClose() {
CloseReadSide();
CloseWriteSide();
if (!fin_sent_ && !rst_sent_) {
// For flow control accounting, tell the peer how many bytes have been
// written on this stream before termination. Done here if needed, using a
// RST_STREAM frame.
DVLOG(1) << ENDPOINT << "Sending RST_STREAM in OnClose: " << id();
session_->SendRstStream(id(), QUIC_RST_ACKNOWLEDGEMENT,
stream_bytes_written_);
rst_sent_ = true;
}
// The stream is being closed and will not process any further incoming bytes.
// As there may be more bytes in flight, to ensure that both endpoints have
// the same connection level flow control state, mark all unreceived or
// buffered bytes as consumed.
QuicByteCount bytes_to_consume =
flow_controller_.highest_received_byte_offset() -
flow_controller_.bytes_consumed();
AddBytesConsumed(bytes_to_consume);
}
void ReliableQuicStream::OnWindowUpdateFrame(
const QuicWindowUpdateFrame& frame) {
if (flow_controller_.UpdateSendWindowOffset(frame.byte_offset)) {
// Writing can be done again!
// TODO(rjshade): This does not respect priorities (e.g. multiple
// outstanding POSTs are unblocked on arrival of
// SHLO with initial window).
// As long as the connection is not flow control blocked, write on!
OnCanWrite();
}
}
bool ReliableQuicStream::MaybeIncreaseHighestReceivedOffset(
QuicStreamOffset new_offset) {
uint64_t increment =
new_offset - flow_controller_.highest_received_byte_offset();
if (!flow_controller_.UpdateHighestReceivedOffset(new_offset)) {
return false;
}
// If |new_offset| increased the stream flow controller's highest received
// offset, increase the connection flow controller's value by the incremental
// difference.
if (stream_contributes_to_connection_flow_control_) {
connection_flow_controller_->UpdateHighestReceivedOffset(
connection_flow_controller_->highest_received_byte_offset() +
increment);
}
return true;
}
void ReliableQuicStream::AddBytesSent(QuicByteCount bytes) {
flow_controller_.AddBytesSent(bytes);
if (stream_contributes_to_connection_flow_control_) {
connection_flow_controller_->AddBytesSent(bytes);
}
}
void ReliableQuicStream::AddBytesConsumed(QuicByteCount bytes) {
// Only adjust stream level flow controller if still reading.
if (!read_side_closed_) {
flow_controller_.AddBytesConsumed(bytes);
}
if (stream_contributes_to_connection_flow_control_) {
connection_flow_controller_->AddBytesConsumed(bytes);
}
}
void ReliableQuicStream::UpdateSendWindowOffset(QuicStreamOffset new_window) {
if (flow_controller_.UpdateSendWindowOffset(new_window)) {
OnCanWrite();
}
}
} // namespace net
|