| // Copyright (c) 2018 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 "quiche/quic/core/qpack/qpack_decoder.h" |
| |
| #include <utility> |
| |
| #include "absl/strings/string_view.h" |
| #include "quiche/quic/core/qpack/qpack_index_conversions.h" |
| #include "quiche/quic/platform/api/quic_flag_utils.h" |
| #include "quiche/quic/platform/api/quic_flags.h" |
| #include "quiche/quic/platform/api/quic_logging.h" |
| |
| namespace quic { |
| |
| QpackDecoder::QpackDecoder( |
| uint64_t maximum_dynamic_table_capacity, uint64_t maximum_blocked_streams, |
| EncoderStreamErrorDelegate* encoder_stream_error_delegate) |
| : encoder_stream_error_delegate_(encoder_stream_error_delegate), |
| encoder_stream_receiver_(this), |
| maximum_blocked_streams_(maximum_blocked_streams), |
| known_received_count_(0) { |
| QUICHE_DCHECK(encoder_stream_error_delegate_); |
| |
| header_table_.SetMaximumDynamicTableCapacity(maximum_dynamic_table_capacity); |
| } |
| |
| QpackDecoder::~QpackDecoder() {} |
| |
| void QpackDecoder::OnStreamReset(QuicStreamId stream_id) { |
| if (header_table_.maximum_dynamic_table_capacity() > 0) { |
| decoder_stream_sender_.SendStreamCancellation(stream_id); |
| decoder_stream_sender_.Flush(); |
| } |
| } |
| |
| bool QpackDecoder::OnStreamBlocked(QuicStreamId stream_id) { |
| auto result = blocked_streams_.insert(stream_id); |
| QUICHE_DCHECK(result.second); |
| return blocked_streams_.size() <= maximum_blocked_streams_; |
| } |
| |
| void QpackDecoder::OnStreamUnblocked(QuicStreamId stream_id) { |
| size_t result = blocked_streams_.erase(stream_id); |
| QUICHE_DCHECK_EQ(1u, result); |
| } |
| |
| void QpackDecoder::OnDecodingCompleted(QuicStreamId stream_id, |
| uint64_t required_insert_count) { |
| if (required_insert_count > 0) { |
| decoder_stream_sender_.SendHeaderAcknowledgement(stream_id); |
| |
| if (known_received_count_ < required_insert_count) { |
| known_received_count_ = required_insert_count; |
| } |
| } |
| |
| // Send an Insert Count Increment instruction if not all dynamic table entries |
| // have been acknowledged yet. This is necessary for efficient compression in |
| // case the encoder chooses not to reference unacknowledged dynamic table |
| // entries, otherwise inserted entries would never be acknowledged. |
| if (known_received_count_ < header_table_.inserted_entry_count()) { |
| decoder_stream_sender_.SendInsertCountIncrement( |
| header_table_.inserted_entry_count() - known_received_count_); |
| known_received_count_ = header_table_.inserted_entry_count(); |
| } |
| |
| decoder_stream_sender_.Flush(); |
| } |
| |
| void QpackDecoder::OnInsertWithNameReference(bool is_static, |
| uint64_t name_index, |
| absl::string_view value) { |
| if (is_static) { |
| auto entry = header_table_.LookupEntry(/* is_static = */ true, name_index); |
| if (!entry) { |
| OnErrorDetected(QUIC_QPACK_ENCODER_STREAM_INVALID_STATIC_ENTRY, |
| "Invalid static table entry."); |
| return; |
| } |
| |
| if (!header_table_.EntryFitsDynamicTableCapacity(entry->name(), value)) { |
| OnErrorDetected(QUIC_QPACK_ENCODER_STREAM_ERROR_INSERTING_STATIC, |
| "Error inserting entry with name reference."); |
| return; |
| } |
| header_table_.InsertEntry(entry->name(), value); |
| return; |
| } |
| |
| uint64_t absolute_index; |
| if (!QpackEncoderStreamRelativeIndexToAbsoluteIndex( |
| name_index, header_table_.inserted_entry_count(), &absolute_index)) { |
| OnErrorDetected(QUIC_QPACK_ENCODER_STREAM_INSERTION_INVALID_RELATIVE_INDEX, |
| "Invalid relative index."); |
| return; |
| } |
| |
| const QpackEntry* entry = |
| header_table_.LookupEntry(/* is_static = */ false, absolute_index); |
| if (!entry) { |
| OnErrorDetected(QUIC_QPACK_ENCODER_STREAM_INSERTION_DYNAMIC_ENTRY_NOT_FOUND, |
| "Dynamic table entry not found."); |
| return; |
| } |
| if (!header_table_.EntryFitsDynamicTableCapacity(entry->name(), value)) { |
| OnErrorDetected(QUIC_QPACK_ENCODER_STREAM_ERROR_INSERTING_DYNAMIC, |
| "Error inserting entry with name reference."); |
| return; |
| } |
| header_table_.InsertEntry(entry->name(), value); |
| } |
| |
| void QpackDecoder::OnInsertWithoutNameReference(absl::string_view name, |
| absl::string_view value) { |
| if (!header_table_.EntryFitsDynamicTableCapacity(name, value)) { |
| OnErrorDetected(QUIC_QPACK_ENCODER_STREAM_ERROR_INSERTING_LITERAL, |
| "Error inserting literal entry."); |
| return; |
| } |
| header_table_.InsertEntry(name, value); |
| } |
| |
| void QpackDecoder::OnDuplicate(uint64_t index) { |
| uint64_t absolute_index; |
| if (!QpackEncoderStreamRelativeIndexToAbsoluteIndex( |
| index, header_table_.inserted_entry_count(), &absolute_index)) { |
| OnErrorDetected(QUIC_QPACK_ENCODER_STREAM_DUPLICATE_INVALID_RELATIVE_INDEX, |
| "Invalid relative index."); |
| return; |
| } |
| |
| const QpackEntry* entry = |
| header_table_.LookupEntry(/* is_static = */ false, absolute_index); |
| if (!entry) { |
| OnErrorDetected(QUIC_QPACK_ENCODER_STREAM_DUPLICATE_DYNAMIC_ENTRY_NOT_FOUND, |
| "Dynamic table entry not found."); |
| return; |
| } |
| if (!header_table_.EntryFitsDynamicTableCapacity(entry->name(), |
| entry->value())) { |
| // This is impossible since entry was retrieved from the dynamic table. |
| OnErrorDetected(QUIC_INTERNAL_ERROR, "Error inserting duplicate entry."); |
| return; |
| } |
| header_table_.InsertEntry(entry->name(), entry->value()); |
| } |
| |
| void QpackDecoder::OnSetDynamicTableCapacity(uint64_t capacity) { |
| if (!header_table_.SetDynamicTableCapacity(capacity)) { |
| OnErrorDetected(QUIC_QPACK_ENCODER_STREAM_SET_DYNAMIC_TABLE_CAPACITY, |
| "Error updating dynamic table capacity."); |
| } |
| } |
| |
| void QpackDecoder::OnErrorDetected(QuicErrorCode error_code, |
| absl::string_view error_message) { |
| encoder_stream_error_delegate_->OnEncoderStreamError(error_code, |
| error_message); |
| } |
| |
| std::unique_ptr<QpackProgressiveDecoder> QpackDecoder::CreateProgressiveDecoder( |
| QuicStreamId stream_id, |
| QpackProgressiveDecoder::HeadersHandlerInterface* handler) { |
| return std::make_unique<QpackProgressiveDecoder>(stream_id, this, this, |
| &header_table_, handler); |
| } |
| |
| } // namespace quic |