| OLD | NEW |
|---|
| (Empty) |
| 1 // Copyright (c) 2012 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/quic/quic_packet_creator.h" | |
| 6 | |
| 7 #include "base/basictypes.h" | |
| 8 #include "base/logging.h" | |
| 9 #include "net/quic/crypto/quic_random.h" | |
| 10 #include "net/quic/quic_ack_notifier.h" | |
| 11 #include "net/quic/quic_data_writer.h" | |
| 12 #include "net/quic/quic_fec_group.h" | |
| 13 #include "net/quic/quic_utils.h" | |
| 14 | |
| 15 using base::StringPiece; | |
| 16 using std::make_pair; | |
| 17 using std::max; | |
| 18 using std::min; | |
| 19 using std::pair; | |
| 20 using std::vector; | |
| 21 | |
| 22 namespace net { | |
| 23 | |
| 24 namespace { | |
| 25 | |
| 26 // Default max packets in an FEC group. | |
| 27 static const size_t kDefaultMaxPacketsPerFecGroup = 10; | |
| 28 // Lowest max packets in an FEC group. | |
| 29 static const size_t kLowestMaxPacketsPerFecGroup = 2; | |
| 30 | |
| 31 } // namespace | |
| 32 | |
| 33 // A QuicRandom wrapper that gets a bucket of entropy and distributes it | |
| 34 // bit-by-bit. Replenishes the bucket as needed. Not thread-safe. Expose this | |
| 35 // class if single bit randomness is needed elsewhere. | |
| 36 class QuicRandomBoolSource { | |
| 37 public: | |
| 38 // random: Source of entropy. Not owned. | |
| 39 explicit QuicRandomBoolSource(QuicRandom* random) | |
| 40 : random_(random), | |
| 41 bit_bucket_(0), | |
| 42 bit_mask_(0) {} | |
| 43 | |
| 44 ~QuicRandomBoolSource() {} | |
| 45 | |
| 46 // Returns the next random bit from the bucket. | |
| 47 bool RandBool() { | |
| 48 if (bit_mask_ == 0) { | |
| 49 bit_bucket_ = random_->RandUint64(); | |
| 50 bit_mask_ = 1; | |
| 51 } | |
| 52 bool result = ((bit_bucket_ & bit_mask_) != 0); | |
| 53 bit_mask_ <<= 1; | |
| 54 return result; | |
| 55 } | |
| 56 | |
| 57 private: | |
| 58 // Source of entropy. | |
| 59 QuicRandom* random_; | |
| 60 // Stored random bits. | |
| 61 uint64 bit_bucket_; | |
| 62 // The next available bit has "1" in the mask. Zero means empty bucket. | |
| 63 uint64 bit_mask_; | |
| 64 | |
| 65 DISALLOW_COPY_AND_ASSIGN(QuicRandomBoolSource); | |
| 66 }; | |
| 67 | |
| 68 QuicPacketCreator::QuicPacketCreator(QuicConnectionId connection_id, | |
| 69 QuicFramer* framer, | |
| 70 QuicRandom* random_generator) | |
| 71 : connection_id_(connection_id), | |
| 72 encryption_level_(ENCRYPTION_NONE), | |
| 73 framer_(framer), | |
| 74 random_bool_source_(new QuicRandomBoolSource(random_generator)), | |
| 75 sequence_number_(0), | |
| 76 should_fec_protect_(false), | |
| 77 fec_group_number_(0), | |
| 78 send_version_in_packet_(!framer->is_server()), | |
| 79 max_packet_length_(kDefaultMaxPacketSize), | |
| 80 max_packets_per_fec_group_(kDefaultMaxPacketsPerFecGroup), | |
| 81 connection_id_length_(PACKET_8BYTE_CONNECTION_ID), | |
| 82 next_sequence_number_length_(PACKET_1BYTE_SEQUENCE_NUMBER), | |
| 83 sequence_number_length_(next_sequence_number_length_), | |
| 84 packet_size_(0) { | |
| 85 framer_->set_fec_builder(this); | |
| 86 } | |
| 87 | |
| 88 QuicPacketCreator::~QuicPacketCreator() { | |
| 89 } | |
| 90 | |
| 91 void QuicPacketCreator::OnBuiltFecProtectedPayload( | |
| 92 const QuicPacketHeader& header, StringPiece payload) { | |
| 93 if (fec_group_.get()) { | |
| 94 DCHECK_NE(0u, header.fec_group); | |
| 95 fec_group_->Update(encryption_level_, header, payload); | |
| 96 } | |
| 97 } | |
| 98 | |
| 99 void QuicPacketCreator::set_max_packets_per_fec_group( | |
| 100 size_t max_packets_per_fec_group) { | |
| 101 max_packets_per_fec_group_ = max(kLowestMaxPacketsPerFecGroup, | |
| 102 max_packets_per_fec_group); | |
| 103 DCHECK_LT(0u, max_packets_per_fec_group_); | |
| 104 } | |
| 105 | |
| 106 bool QuicPacketCreator::ShouldSendFec(bool force_close) const { | |
| 107 DCHECK(!HasPendingFrames()); | |
| 108 return fec_group_.get() != nullptr && fec_group_->NumReceivedPackets() > 0 && | |
| 109 (force_close || | |
| 110 fec_group_->NumReceivedPackets() >= max_packets_per_fec_group_); | |
| 111 } | |
| 112 | |
| 113 bool QuicPacketCreator::IsFecGroupOpen() const { | |
| 114 return fec_group_.get() != nullptr; | |
| 115 } | |
| 116 | |
| 117 void QuicPacketCreator::StartFecProtectingPackets() { | |
| 118 if (!IsFecEnabled()) { | |
| 119 LOG(DFATAL) << "Cannot start FEC protection when FEC is not enabled."; | |
| 120 return; | |
| 121 } | |
| 122 // TODO(jri): This currently requires that the generator flush out any | |
| 123 // pending frames when FEC protection is turned on. If current packet can be | |
| 124 // converted to an FEC protected packet, do it. This will require the | |
| 125 // generator to check if the resulting expansion still allows the incoming | |
| 126 // frame to be added to the packet. | |
| 127 if (HasPendingFrames()) { | |
| 128 LOG(DFATAL) << "Cannot start FEC protection with pending frames."; | |
| 129 return; | |
| 130 } | |
| 131 DCHECK(!should_fec_protect_); | |
| 132 should_fec_protect_ = true; | |
| 133 } | |
| 134 | |
| 135 void QuicPacketCreator::StopFecProtectingPackets() { | |
| 136 if (fec_group_.get() != nullptr) { | |
| 137 LOG(DFATAL) << "Cannot stop FEC protection with open FEC group."; | |
| 138 return; | |
| 139 } | |
| 140 DCHECK(should_fec_protect_); | |
| 141 should_fec_protect_ = false; | |
| 142 fec_group_number_ = 0; | |
| 143 } | |
| 144 | |
| 145 bool QuicPacketCreator::IsFecProtected() const { | |
| 146 return should_fec_protect_; | |
| 147 } | |
| 148 | |
| 149 bool QuicPacketCreator::IsFecEnabled() const { | |
| 150 return max_packets_per_fec_group_ > 0; | |
| 151 } | |
| 152 | |
| 153 InFecGroup QuicPacketCreator::MaybeUpdateLengthsAndStartFec() { | |
| 154 if (fec_group_.get() != nullptr) { | |
| 155 // Don't update any lengths when an FEC group is open, to ensure same | |
| 156 // packet header size in all packets within a group. | |
| 157 return IN_FEC_GROUP; | |
| 158 } | |
| 159 if (!queued_frames_.empty()) { | |
| 160 // Don't change creator state if there are frames queued. | |
| 161 return fec_group_.get() == nullptr ? NOT_IN_FEC_GROUP : IN_FEC_GROUP; | |
| 162 } | |
| 163 | |
| 164 // Update sequence number length only on packet and FEC group boundaries. | |
| 165 sequence_number_length_ = next_sequence_number_length_; | |
| 166 | |
| 167 if (!should_fec_protect_) { | |
| 168 return NOT_IN_FEC_GROUP; | |
| 169 } | |
| 170 // Start a new FEC group since protection is on. Set the fec group number to | |
| 171 // the sequence number of the next packet. | |
| 172 fec_group_number_ = sequence_number() + 1; | |
| 173 fec_group_.reset(new QuicFecGroup()); | |
| 174 return IN_FEC_GROUP; | |
| 175 } | |
| 176 | |
| 177 // Stops serializing version of the protocol in packets sent after this call. | |
| 178 // A packet that is already open might send kQuicVersionSize bytes less than the | |
| 179 // maximum packet size if we stop sending version before it is serialized. | |
| 180 void QuicPacketCreator::StopSendingVersion() { | |
| 181 DCHECK(send_version_in_packet_); | |
| 182 send_version_in_packet_ = false; | |
| 183 if (packet_size_ > 0) { | |
| 184 DCHECK_LT(kQuicVersionSize, packet_size_); | |
| 185 packet_size_ -= kQuicVersionSize; | |
| 186 } | |
| 187 } | |
| 188 | |
| 189 void QuicPacketCreator::UpdateSequenceNumberLength( | |
| 190 QuicPacketSequenceNumber least_packet_awaited_by_peer, | |
| 191 QuicPacketCount max_packets_in_flight) { | |
| 192 DCHECK_LE(least_packet_awaited_by_peer, sequence_number_ + 1); | |
| 193 // Since the packet creator will not change sequence number length mid FEC | |
| 194 // group, include the size of an FEC group to be safe. | |
| 195 const QuicPacketSequenceNumber current_delta = | |
| 196 max_packets_per_fec_group_ + sequence_number_ + 1 | |
| 197 - least_packet_awaited_by_peer; | |
| 198 const uint64 delta = max(current_delta, max_packets_in_flight); | |
| 199 next_sequence_number_length_ = | |
| 200 QuicFramer::GetMinSequenceNumberLength(delta * 4); | |
| 201 } | |
| 202 | |
| 203 bool QuicPacketCreator::HasRoomForStreamFrame(QuicStreamId id, | |
| 204 QuicStreamOffset offset) const { | |
| 205 // TODO(jri): This is a simple safe decision for now, but make | |
| 206 // is_in_fec_group a parameter. Same as with all public methods in | |
| 207 // QuicPacketCreator. | |
| 208 return BytesFree() > | |
| 209 QuicFramer::GetMinStreamFrameSize(id, offset, true, | |
| 210 should_fec_protect_ ? IN_FEC_GROUP : | |
| 211 NOT_IN_FEC_GROUP); | |
| 212 } | |
| 213 | |
| 214 // static | |
| 215 size_t QuicPacketCreator::StreamFramePacketOverhead( | |
| 216 QuicConnectionIdLength connection_id_length, | |
| 217 bool include_version, | |
| 218 QuicSequenceNumberLength sequence_number_length, | |
| 219 QuicStreamOffset offset, | |
| 220 InFecGroup is_in_fec_group) { | |
| 221 return GetPacketHeaderSize(connection_id_length, include_version, | |
| 222 sequence_number_length, is_in_fec_group) + | |
| 223 // Assumes this is a stream with a single lone packet. | |
| 224 QuicFramer::GetMinStreamFrameSize(1u, offset, true, is_in_fec_group); | |
| 225 } | |
| 226 | |
| 227 size_t QuicPacketCreator::CreateStreamFrame(QuicStreamId id, | |
| 228 const IOVector& data, | |
| 229 QuicStreamOffset offset, | |
| 230 bool fin, | |
| 231 QuicFrame* frame) { | |
| 232 DCHECK_GT(max_packet_length_, StreamFramePacketOverhead( | |
| 233 connection_id_length_, kIncludeVersion, | |
| 234 PACKET_6BYTE_SEQUENCE_NUMBER, offset, IN_FEC_GROUP)); | |
| 235 | |
| 236 InFecGroup is_in_fec_group = MaybeUpdateLengthsAndStartFec(); | |
| 237 | |
| 238 LOG_IF(DFATAL, !HasRoomForStreamFrame(id, offset)) | |
| 239 << "No room for Stream frame, BytesFree: " << BytesFree() | |
| 240 << " MinStreamFrameSize: " | |
| 241 << QuicFramer::GetMinStreamFrameSize(id, offset, true, is_in_fec_group); | |
| 242 | |
| 243 if (data.Empty()) { | |
| 244 LOG_IF(DFATAL, !fin) | |
| 245 << "Creating a stream frame with no data or fin."; | |
| 246 // Create a new packet for the fin, if necessary. | |
| 247 *frame = QuicFrame(new QuicStreamFrame(id, true, offset, data)); | |
| 248 return 0; | |
| 249 } | |
| 250 | |
| 251 const size_t data_size = data.TotalBufferSize(); | |
| 252 size_t min_frame_size = QuicFramer::GetMinStreamFrameSize( | |
| 253 id, offset, /* last_frame_in_packet= */ true, is_in_fec_group); | |
| 254 size_t bytes_consumed = min<size_t>(BytesFree() - min_frame_size, data_size); | |
| 255 | |
| 256 bool set_fin = fin && bytes_consumed == data_size; // Last frame. | |
| 257 IOVector frame_data; | |
| 258 frame_data.AppendIovecAtMostBytes(data.iovec(), data.Size(), | |
| 259 bytes_consumed); | |
| 260 DCHECK_EQ(frame_data.TotalBufferSize(), bytes_consumed); | |
| 261 *frame = QuicFrame(new QuicStreamFrame(id, set_fin, offset, frame_data)); | |
| 262 return bytes_consumed; | |
| 263 } | |
| 264 | |
| 265 SerializedPacket QuicPacketCreator::ReserializeAllFrames( | |
| 266 const RetransmittableFrames& frames, | |
| 267 QuicSequenceNumberLength original_length) { | |
| 268 DCHECK(fec_group_.get() == nullptr); | |
| 269 const QuicSequenceNumberLength saved_length = sequence_number_length_; | |
| 270 const QuicSequenceNumberLength saved_next_length = | |
| 271 next_sequence_number_length_; | |
| 272 const bool saved_should_fec_protect = should_fec_protect_; | |
| 273 const EncryptionLevel default_encryption_level = encryption_level_; | |
| 274 | |
| 275 // Temporarily set the sequence number length, stop FEC protection, | |
| 276 // and change the encryption level. | |
| 277 sequence_number_length_ = original_length; | |
| 278 next_sequence_number_length_ = original_length; | |
| 279 should_fec_protect_ = false; | |
| 280 encryption_level_ = frames.encryption_level(); | |
| 281 | |
| 282 // Serialize the packet and restore the FEC and sequence number length state. | |
| 283 SerializedPacket serialized_packet = SerializeAllFrames(frames.frames()); | |
| 284 sequence_number_length_ = saved_length; | |
| 285 next_sequence_number_length_ = saved_next_length; | |
| 286 should_fec_protect_ = saved_should_fec_protect; | |
| 287 encryption_level_ = default_encryption_level; | |
| 288 | |
| 289 return serialized_packet; | |
| 290 } | |
| 291 | |
| 292 // TODO(ianswett): Remove this method, because it's test only. | |
| 293 SerializedPacket QuicPacketCreator::SerializeAllFrames( | |
| 294 const QuicFrames& frames) { | |
| 295 // TODO(satyamshekhar): Verify that this DCHECK won't fail. What about queued | |
| 296 // frames from SendStreamData()[send_stream_should_flush_ == false && | |
| 297 // data.empty() == true] and retransmit due to RTO. | |
| 298 DCHECK_EQ(0u, queued_frames_.size()); | |
| 299 LOG_IF(DFATAL, frames.empty()) | |
| 300 << "Attempt to serialize empty packet"; | |
| 301 for (const QuicFrame& frame : frames) { | |
| 302 bool success = AddFrame(frame, false); | |
| 303 DCHECK(success); | |
| 304 } | |
| 305 SerializedPacket packet = SerializePacket(); | |
| 306 DCHECK(packet.retransmittable_frames == nullptr); | |
| 307 return packet; | |
| 308 } | |
| 309 | |
| 310 bool QuicPacketCreator::HasPendingFrames() const { | |
| 311 return !queued_frames_.empty(); | |
| 312 } | |
| 313 | |
| 314 bool QuicPacketCreator::HasPendingRetransmittableFrames() const { | |
| 315 return queued_retransmittable_frames_.get() != nullptr && | |
| 316 !queued_retransmittable_frames_->frames().empty(); | |
| 317 } | |
| 318 | |
| 319 size_t QuicPacketCreator::ExpansionOnNewFrame() const { | |
| 320 // If packet is FEC protected, there's no expansion. | |
| 321 if (should_fec_protect_) { | |
| 322 return 0; | |
| 323 } | |
| 324 // If the last frame in the packet is a stream frame, then it will expand to | |
| 325 // include the stream_length field when a new frame is added. | |
| 326 bool has_trailing_stream_frame = | |
| 327 !queued_frames_.empty() && queued_frames_.back().type == STREAM_FRAME; | |
| 328 return has_trailing_stream_frame ? kQuicStreamPayloadLengthSize : 0; | |
| 329 } | |
| 330 | |
| 331 size_t QuicPacketCreator::BytesFree() const { | |
| 332 const size_t max_plaintext_size = | |
| 333 framer_->GetMaxPlaintextSize(max_packet_length_); | |
| 334 DCHECK_GE(max_plaintext_size, PacketSize()); | |
| 335 return max_plaintext_size - min(max_plaintext_size, PacketSize() | |
| 336 + ExpansionOnNewFrame()); | |
| 337 } | |
| 338 | |
| 339 size_t QuicPacketCreator::PacketSize() const { | |
| 340 if (!queued_frames_.empty()) { | |
| 341 return packet_size_; | |
| 342 } | |
| 343 if (fec_group_.get() == nullptr) { | |
| 344 // Update sequence number length on packet and FEC boundary. | |
| 345 sequence_number_length_ = next_sequence_number_length_; | |
| 346 } | |
| 347 packet_size_ = GetPacketHeaderSize( | |
| 348 connection_id_length_, send_version_in_packet_, sequence_number_length_, | |
| 349 should_fec_protect_ ? IN_FEC_GROUP : NOT_IN_FEC_GROUP); | |
| 350 return packet_size_; | |
| 351 } | |
| 352 | |
| 353 bool QuicPacketCreator::AddSavedFrame(const QuicFrame& frame) { | |
| 354 return AddFrame(frame, true); | |
| 355 } | |
| 356 | |
| 357 SerializedPacket QuicPacketCreator::SerializePacket() { | |
| 358 LOG_IF(DFATAL, queued_frames_.empty()) | |
| 359 << "Attempt to serialize empty packet"; | |
| 360 DCHECK_GE(sequence_number_ + 1, fec_group_number_); | |
| 361 QuicPacketHeader header; | |
| 362 FillPacketHeader(should_fec_protect_ ? fec_group_number_ : 0, false, &header); | |
| 363 | |
| 364 MaybeAddPadding(); | |
| 365 | |
| 366 size_t max_plaintext_size = | |
| 367 framer_->GetMaxPlaintextSize(max_packet_length_); | |
| 368 DCHECK_GE(max_plaintext_size, packet_size_); | |
| 369 // ACK Frames will be truncated due to length only if they're the only frame | |
| 370 // in the packet, and if packet_size_ was set to max_plaintext_size. If | |
| 371 // truncation due to length occurred, then GetSerializedFrameLength will have | |
| 372 // returned all bytes free. | |
| 373 bool possibly_truncated_by_length = packet_size_ == max_plaintext_size && | |
| 374 queued_frames_.size() == 1 && | |
| 375 queued_frames_.back().type == ACK_FRAME; | |
| 376 char buffer[kMaxPacketSize]; | |
| 377 scoped_ptr<QuicPacket> packet; | |
| 378 // Use the packet_size_ instead of the buffer size to ensure smaller | |
| 379 // packet sizes are properly used. | |
| 380 scoped_ptr<char[]> large_buffer; | |
| 381 if (packet_size_ <= kMaxPacketSize) { | |
| 382 packet.reset( | |
| 383 framer_->BuildDataPacket(header, queued_frames_, buffer, packet_size_)); | |
| 384 } else { | |
| 385 large_buffer.reset(new char[packet_size_]); | |
| 386 packet.reset(framer_->BuildDataPacket(header, queued_frames_, | |
| 387 large_buffer.get(), packet_size_)); | |
| 388 } | |
| 389 LOG_IF(DFATAL, packet == nullptr) << "Failed to serialize " | |
| 390 << queued_frames_.size() << " frames."; | |
| 391 // Because of possible truncation, we can't be confident that our | |
| 392 // packet size calculation worked correctly. | |
| 393 if (!possibly_truncated_by_length) { | |
| 394 DCHECK_EQ(packet_size_, packet->length()); | |
| 395 } | |
| 396 // Immediately encrypt the packet, to ensure we don't encrypt the same packet | |
| 397 // sequence number multiple times. | |
| 398 QuicEncryptedPacket* encrypted = | |
| 399 framer_->EncryptPacket(encryption_level_, sequence_number_, *packet); | |
| 400 if (encrypted == nullptr) { | |
| 401 LOG(DFATAL) << "Failed to encrypt packet number " << sequence_number_; | |
| 402 SerializedPacket kNoPacket(0, PACKET_1BYTE_SEQUENCE_NUMBER, nullptr, 0, | |
| 403 nullptr); | |
| 404 return kNoPacket; | |
| 405 } | |
| 406 | |
| 407 packet_size_ = 0; | |
| 408 queued_frames_.clear(); | |
| 409 return SerializedPacket(header.packet_sequence_number, | |
| 410 header.public_header.sequence_number_length, | |
| 411 encrypted, QuicFramer::GetPacketEntropyHash(header), | |
| 412 queued_retransmittable_frames_.release()); | |
| 413 } | |
| 414 | |
| 415 SerializedPacket QuicPacketCreator::SerializeFec() { | |
| 416 if (fec_group_.get() == nullptr || fec_group_->NumReceivedPackets() <= 0) { | |
| 417 LOG(DFATAL) << "SerializeFEC called but no group or zero packets in group."; | |
| 418 // TODO(jri): Make this a public method of framer? | |
| 419 SerializedPacket kNoPacket(0, PACKET_1BYTE_SEQUENCE_NUMBER, nullptr, 0, | |
| 420 nullptr); | |
| 421 return kNoPacket; | |
| 422 } | |
| 423 DCHECK_EQ(0u, queued_frames_.size()); | |
| 424 QuicPacketHeader header; | |
| 425 FillPacketHeader(fec_group_number_, true, &header); | |
| 426 QuicFecData fec_data; | |
| 427 fec_data.fec_group = fec_group_->min_protected_packet(); | |
| 428 fec_data.redundancy = fec_group_->payload_parity(); | |
| 429 scoped_ptr<QuicPacket> packet(framer_->BuildFecPacket(header, fec_data)); | |
| 430 fec_group_.reset(nullptr); | |
| 431 packet_size_ = 0; | |
| 432 LOG_IF(DFATAL, packet == nullptr) | |
| 433 << "Failed to serialize fec packet for group:" << fec_data.fec_group; | |
| 434 DCHECK_GE(max_packet_length_, packet->length()); | |
| 435 // Immediately encrypt the packet, to ensure we don't encrypt the same packet | |
| 436 // sequence number multiple times. | |
| 437 QuicEncryptedPacket* encrypted = | |
| 438 framer_->EncryptPacket(encryption_level_, sequence_number_, *packet); | |
| 439 if (encrypted == nullptr) { | |
| 440 LOG(DFATAL) << "Failed to encrypt packet number " << sequence_number_; | |
| 441 SerializedPacket kNoPacket(0, PACKET_1BYTE_SEQUENCE_NUMBER, nullptr, 0, | |
| 442 nullptr); | |
| 443 return kNoPacket; | |
| 444 } | |
| 445 SerializedPacket serialized( | |
| 446 header.packet_sequence_number, | |
| 447 header.public_header.sequence_number_length, encrypted, | |
| 448 QuicFramer::GetPacketEntropyHash(header), nullptr); | |
| 449 serialized.is_fec_packet = true; | |
| 450 return serialized; | |
| 451 } | |
| 452 | |
| 453 SerializedPacket QuicPacketCreator::SerializeConnectionClose( | |
| 454 QuicConnectionCloseFrame* close_frame) { | |
| 455 QuicFrames frames; | |
| 456 frames.push_back(QuicFrame(close_frame)); | |
| 457 return SerializeAllFrames(frames); | |
| 458 } | |
| 459 | |
| 460 QuicEncryptedPacket* QuicPacketCreator::SerializeVersionNegotiationPacket( | |
| 461 const QuicVersionVector& supported_versions) { | |
| 462 DCHECK(framer_->is_server()); | |
| 463 QuicPacketPublicHeader header; | |
| 464 header.connection_id = connection_id_; | |
| 465 header.reset_flag = false; | |
| 466 header.version_flag = true; | |
| 467 header.versions = supported_versions; | |
| 468 QuicEncryptedPacket* encrypted = | |
| 469 framer_->BuildVersionNegotiationPacket(header, supported_versions); | |
| 470 DCHECK(encrypted); | |
| 471 DCHECK_GE(max_packet_length_, encrypted->length()); | |
| 472 return encrypted; | |
| 473 } | |
| 474 | |
| 475 void QuicPacketCreator::FillPacketHeader(QuicFecGroupNumber fec_group, | |
| 476 bool fec_flag, | |
| 477 QuicPacketHeader* header) { | |
| 478 header->public_header.connection_id = connection_id_; | |
| 479 header->public_header.connection_id_length = connection_id_length_; | |
| 480 header->public_header.reset_flag = false; | |
| 481 header->public_header.version_flag = send_version_in_packet_; | |
| 482 header->fec_flag = fec_flag; | |
| 483 header->packet_sequence_number = ++sequence_number_; | |
| 484 header->public_header.sequence_number_length = sequence_number_length_; | |
| 485 header->entropy_flag = random_bool_source_->RandBool(); | |
| 486 header->is_in_fec_group = fec_group == 0 ? NOT_IN_FEC_GROUP : IN_FEC_GROUP; | |
| 487 header->fec_group = fec_group; | |
| 488 } | |
| 489 | |
| 490 bool QuicPacketCreator::ShouldRetransmit(const QuicFrame& frame) { | |
| 491 switch (frame.type) { | |
| 492 case ACK_FRAME: | |
| 493 case PADDING_FRAME: | |
| 494 case STOP_WAITING_FRAME: | |
| 495 return false; | |
| 496 default: | |
| 497 return true; | |
| 498 } | |
| 499 } | |
| 500 | |
| 501 bool QuicPacketCreator::AddFrame(const QuicFrame& frame, | |
| 502 bool save_retransmittable_frames) { | |
| 503 DVLOG(1) << "Adding frame: " << frame; | |
| 504 InFecGroup is_in_fec_group = MaybeUpdateLengthsAndStartFec(); | |
| 505 | |
| 506 size_t frame_len = framer_->GetSerializedFrameLength( | |
| 507 frame, BytesFree(), queued_frames_.empty(), true, is_in_fec_group, | |
| 508 sequence_number_length_); | |
| 509 if (frame_len == 0) { | |
| 510 return false; | |
| 511 } | |
| 512 DCHECK_LT(0u, packet_size_); | |
| 513 packet_size_ += ExpansionOnNewFrame() + frame_len; | |
| 514 | |
| 515 if (save_retransmittable_frames && ShouldRetransmit(frame)) { | |
| 516 if (queued_retransmittable_frames_.get() == nullptr) { | |
| 517 queued_retransmittable_frames_.reset(new RetransmittableFrames()); | |
| 518 } | |
| 519 if (frame.type == STREAM_FRAME) { | |
| 520 queued_frames_.push_back( | |
| 521 queued_retransmittable_frames_->AddStreamFrame(frame.stream_frame)); | |
| 522 } else { | |
| 523 queued_frames_.push_back( | |
| 524 queued_retransmittable_frames_->AddNonStreamFrame(frame)); | |
| 525 } | |
| 526 } else { | |
| 527 queued_frames_.push_back(frame); | |
| 528 } | |
| 529 return true; | |
| 530 } | |
| 531 | |
| 532 void QuicPacketCreator::MaybeAddPadding() { | |
| 533 if (BytesFree() == 0) { | |
| 534 // Don't pad full packets. | |
| 535 return; | |
| 536 } | |
| 537 | |
| 538 // Since ReserializeAllFrames does not populate queued_retransmittable_frames_ | |
| 539 // it's not sufficient to simply call | |
| 540 // queued_retransmittable_frames_->HasCryptoHandshake(). | |
| 541 // TODO(rch): we should really make ReserializeAllFrames not be a special | |
| 542 // case! | |
| 543 | |
| 544 // If any of the frames in the current packet are on the crypto stream | |
| 545 // then they contain handshake messagses, and we should pad them. | |
| 546 bool is_handshake = false; | |
| 547 for (const QuicFrame& frame : queued_frames_) { | |
| 548 if (frame.type == STREAM_FRAME && | |
| 549 frame.stream_frame->stream_id == kCryptoStreamId) { | |
| 550 is_handshake = true; | |
| 551 break; | |
| 552 } | |
| 553 } | |
| 554 if (!is_handshake) { | |
| 555 return; | |
| 556 } | |
| 557 | |
| 558 QuicPaddingFrame padding; | |
| 559 bool success = AddFrame(QuicFrame(&padding), false); | |
| 560 DCHECK(success); | |
| 561 } | |
| 562 | |
| 563 } // namespace net | |
| OLD | NEW |
|---|
Chromium Code Reviews
Issue 992733002:
Remove //net (except for Android test stuff) and sdch (Closed)
Base URL: git@github.com:domokit/mojo.git@master