| // Copyright 2016 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/spdy/hpack/hpack_decoder2.h" |
| |
| #include <list> |
| #include <utility> |
| |
| #include "base/logging.h" |
| #include "base/strings/string_piece.h" |
| #include "net/http2/decoder/decode_buffer.h" |
| #include "net/http2/decoder/decode_status.h" |
| #include "net/spdy/hpack/hpack_entry.h" |
| #include "net/spdy/platform/api/spdy_estimate_memory_usage.h" |
| |
| using base::StringPiece; |
| |
| namespace net { |
| |
| HpackDecoder2::HpackDecoder2() : hpack_block_decoder_(this) { |
| Reset(); |
| } |
| |
| HpackDecoder2::~HpackDecoder2() {} |
| |
| void HpackDecoder2::Reset() { |
| DVLOG(2) << "HpackDecoder2::Reset"; |
| handler_ = nullptr; |
| |
| hpack_block_decoder_.Reset(); |
| hpack_block_decoder_.set_listener(this); |
| |
| total_hpack_bytes_ = 0; |
| total_header_bytes_ = 0; |
| size_update_count_ = 0; |
| header_seen_ = false; |
| in_progress_ = false; |
| error_detected_ = false; |
| header_block_started_ = false; |
| |
| name_.Reset(); |
| value_.Reset(); |
| } |
| |
| void HpackDecoder2::SetErrorDetected() { |
| if (!error_detected_) { |
| DVLOG(2) << "HpackDecoder2::SetErrorDetected"; |
| hpack_block_decoder_.set_listener(&no_op_listener_); |
| error_detected_ = true; |
| } |
| } |
| |
| void HpackDecoder2::ApplyHeaderTableSizeSetting(size_t size_setting) { |
| DVLOG(2) << "HpackDecoder2::ApplyHeaderTableSizeSetting"; |
| header_table_.SetSettingsHeaderTableSize(size_setting); |
| } |
| |
| // If a SpdyHeadersHandlerInterface is provided, the decoder will emit |
| // headers to it rather than accumulating them in a SpdyHeaderBlock. |
| void HpackDecoder2::HandleControlFrameHeadersStart( |
| SpdyHeadersHandlerInterface* handler) { |
| DVLOG(2) << "HpackDecoder2::HandleControlFrameHeadersStart"; |
| DCHECK(!header_block_started_); |
| handler_ = handler; |
| } |
| |
| // Called as HPACK block fragments arrive. Returns false |
| // if an error occurred while decoding the block. |
| bool HpackDecoder2::HandleControlFrameHeadersData(const char* headers_data, |
| size_t headers_data_length) { |
| DVLOG(2) << "HpackDecoder2::HandleControlFrameHeadersData: len=" |
| << headers_data_length; |
| if (!header_block_started_) { |
| DCHECK_EQ(total_hpack_bytes_, 0u); |
| // Clear the SpdyHeaderBlock here rather than in Reset so that it is NOT |
| // cleared in HandleControlFrameHeadersComplete, which would be before it |
| // could be used. |
| decoded_block_.clear(); |
| header_block_started_ = true; |
| if (handler_ != nullptr) { |
| handler_->OnHeaderBlockStart(); |
| } |
| } |
| |
| // Sometimes we get a call with headers_data==nullptr and |
| // headers_data_length==0, in which case we need to avoid creating |
| // a DecodeBuffer, which would otherwise complain. |
| if (headers_data_length > 0) { |
| DCHECK_NE(headers_data, nullptr); |
| total_hpack_bytes_ += headers_data_length; |
| DecodeBuffer db(headers_data, headers_data_length); |
| DecodeStatus status = hpack_block_decoder_.Decode(&db); |
| switch (status) { |
| case DecodeStatus::kDecodeDone: |
| // We've completed the decoding of headers_data, and it ended at the |
| // boundary between two HPACK block entries, so name_ and value_ are |
| // currently reset. |
| DCHECK_EQ(0u, db.Remaining()); |
| in_progress_ = false; |
| break; |
| |
| case DecodeStatus::kDecodeInProgress: |
| DCHECK_EQ(0u, db.Remaining()); |
| in_progress_ = true; |
| if (!error_detected_) { |
| name_.BufferStringIfUnbuffered(); |
| value_.BufferStringIfUnbuffered(); |
| EnforceMaxDecodeBufferSize(); |
| } |
| break; |
| |
| case DecodeStatus::kDecodeError: |
| SetErrorDetected(); |
| break; |
| } |
| } |
| return !error_detected_; |
| } |
| |
| // Called after a HPACK block has been completely delivered via |
| // HandleControlFrameHeadersData(). Returns false if an error occurred. |
| // |compressed_len| if non-null will be set to the size of the encoded |
| // buffered block that was accumulated in HandleControlFrameHeadersData(), |
| // to support subsequent calculation of compression percentage. |
| // Discards the handler supplied at the start of decoding the block. |
| // TODO(jamessynge): Determine if compressed_len is needed; it is used to |
| // produce UUMA stat Net.SpdyHpackDecompressionPercentage, but only for |
| // SPDY3, not HTTP2. |
| bool HpackDecoder2::HandleControlFrameHeadersComplete(size_t* compressed_len) { |
| DVLOG(2) << "HpackDecoder2::HandleControlFrameHeadersComplete"; |
| if (error_detected_ || in_progress_) { |
| DVLOG(2) << "error_detected_=" << error_detected_ |
| << ", in_progress_=" << in_progress_; |
| return false; |
| } |
| if (compressed_len != nullptr) { |
| *compressed_len = total_hpack_bytes_; |
| } |
| if (handler_ != nullptr) { |
| handler_->OnHeaderBlockEnd(total_header_bytes_); |
| } |
| Reset(); |
| return true; |
| } |
| |
| const SpdyHeaderBlock& HpackDecoder2::decoded_block() const { |
| return decoded_block_; |
| } |
| |
| void HpackDecoder2::SetHeaderTableDebugVisitor( |
| std::unique_ptr<HpackHeaderTable::DebugVisitorInterface> visitor) { |
| DVLOG(2) << "HpackDecoder2::SetHeaderTableDebugVisitor"; |
| header_table_.set_debug_visitor(std::move(visitor)); |
| } |
| |
| void HpackDecoder2::set_max_decode_buffer_size_bytes( |
| size_t max_decode_buffer_size_bytes) { |
| DVLOG(2) << "HpackDecoder2::set_max_decode_buffer_size_bytes"; |
| max_decode_buffer_size_bytes_ = max_decode_buffer_size_bytes; |
| } |
| |
| size_t HpackDecoder2::EstimateMemoryUsage() const { |
| return SpdyEstimateMemoryUsage(header_table_) + |
| SpdyEstimateMemoryUsage(decoded_block_) + |
| SpdyEstimateMemoryUsage(name_) + SpdyEstimateMemoryUsage(value_); |
| } |
| |
| void HpackDecoder2::OnIndexedHeader(size_t index) { |
| DVLOG(2) << "HpackDecoder2::OnIndexedHeader: index=" << index; |
| DCHECK(!error_detected_); |
| const HpackEntry* entry = header_table_.GetByIndex(index); |
| if (entry == nullptr) { |
| SetErrorDetected(); |
| return; |
| } |
| HandleHeaderRepresentation(entry->name(), entry->value()); |
| } |
| |
| void HpackDecoder2::OnStartLiteralHeader(HpackEntryType entry_type, |
| size_t maybe_name_index) { |
| DVLOG(2) << "HpackDecoder2::OnStartLiteralHeader: entry_type=" << entry_type |
| << ", maybe_name_index=" << maybe_name_index; |
| DCHECK(!error_detected_); |
| entry_type_ = entry_type; |
| if (maybe_name_index > 0) { |
| const HpackEntry* entry = header_table_.GetByIndex(maybe_name_index); |
| if (entry == nullptr) { |
| SetErrorDetected(); |
| return; |
| } else { |
| // Non-static entries could be evicted, leaving us with a dangling |
| // pointer, so we preemptively copy. This could be avoided if |
| // TryAddEntry would copy the strings prior to performing eviction. |
| name_.Set(entry->name(), entry->IsStatic()); |
| name_.BufferStringIfUnbuffered(); |
| } |
| } |
| } |
| |
| void HpackDecoder2::OnNameStart(bool huffman_encoded, size_t len) { |
| DVLOG(2) << "HpackDecoder2::OnNameStart: huffman_encoded=" |
| << (huffman_encoded ? "true" : "false") << ", len=" << len; |
| if (len > max_decode_buffer_size_bytes_) { |
| DVLOG(1) << "Name length (" << len << ") is longer than permitted (" |
| << max_decode_buffer_size_bytes_ << ")"; |
| SetErrorDetected(); |
| return; |
| } |
| name_.OnStart(huffman_encoded, len); |
| } |
| |
| void HpackDecoder2::OnNameData(const char* data, size_t len) { |
| DVLOG(2) << "HpackDecoder2::OnNameData: len=" << len |
| << "\n data: " << StringPiece(data, len); |
| if (error_detected_) { |
| return; |
| } |
| if (!name_.OnData(data, len)) { |
| SetErrorDetected(); |
| } |
| } |
| |
| void HpackDecoder2::OnNameEnd() { |
| DVLOG(2) << "HpackDecoder2::OnNameEnd"; |
| if (error_detected_) { |
| return; |
| } |
| if (!name_.OnEnd()) { |
| SetErrorDetected(); |
| } |
| } |
| |
| void HpackDecoder2::OnValueStart(bool huffman_encoded, size_t len) { |
| DVLOG(2) << "HpackDecoder2::OnValueStart: huffman_encoded=" |
| << (huffman_encoded ? "true" : "false") << ", len=" << len; |
| if (len > max_decode_buffer_size_bytes_) { |
| DVLOG(1) << "Value length (" << len << ") is longer than permitted (" |
| << max_decode_buffer_size_bytes_ << ")"; |
| SetErrorDetected(); |
| return; |
| } |
| value_.OnStart(huffman_encoded, len); |
| } |
| |
| void HpackDecoder2::OnValueData(const char* data, size_t len) { |
| DVLOG(2) << "HpackDecoder2::OnValueData: len=" << len |
| << "\n data: " << StringPiece(data, len); |
| if (error_detected_) { |
| return; |
| } |
| if (!value_.OnData(data, len)) { |
| SetErrorDetected(); |
| } |
| } |
| |
| void HpackDecoder2::OnValueEnd() { |
| DVLOG(2) << "HpackDecoder2::OnValueEnd"; |
| if (error_detected_) { |
| return; |
| } |
| if (!value_.OnEnd()) { |
| SetErrorDetected(); |
| return; |
| } |
| if (EnforceMaxDecodeBufferSize()) { |
| // All is well. |
| HandleHeaderRepresentation(name_.str(), value_.str()); |
| if (entry_type_ == HpackEntryType::kIndexedLiteralHeader) { |
| header_table_.TryAddEntry(name_.str(), value_.str()); |
| } |
| name_.Reset(); |
| value_.Reset(); |
| } |
| } |
| |
| void HpackDecoder2::OnDynamicTableSizeUpdate(size_t size) { |
| DVLOG(2) << "HpackDecoder2::OnDynamicTableSizeUpdate: size=" << size; |
| if (error_detected_) { |
| return; |
| } |
| if (size > header_table_.settings_size_bound()) { |
| DVLOG(1) << "Dynamic Table Size Update with too large a size: " << size |
| << " > " << header_table_.settings_size_bound(); |
| SetErrorDetected(); |
| return; |
| } |
| if (header_seen_) { |
| DVLOG(1) << "Dynamic Table Size Update seen after a Header"; |
| SetErrorDetected(); |
| return; |
| } |
| ++size_update_count_; |
| if (size_update_count_ > 2) { |
| DVLOG(1) << "Too many (" << size_update_count_ |
| << ") Dynamic Table Size Updates"; |
| SetErrorDetected(); |
| return; |
| } |
| header_table_.SetMaxSize(size); |
| return; |
| } |
| |
| bool HpackDecoder2::EnforceMaxDecodeBufferSize() { |
| if (!error_detected_) { |
| size_t buffered_length = name_.BufferedLength() + value_.BufferedLength(); |
| DVLOG(2) << "buffered_length=" << buffered_length |
| << "; max=" << max_decode_buffer_size_bytes_; |
| if (buffered_length > max_decode_buffer_size_bytes_) { |
| DVLOG(1) << "Header length (" << buffered_length |
| << ") is longer than permitted (" |
| << max_decode_buffer_size_bytes_ << ")"; |
| SetErrorDetected(); |
| } |
| } |
| return !error_detected_; |
| } |
| |
| void HpackDecoder2::HandleHeaderRepresentation(StringPiece name, |
| StringPiece value) { |
| DVLOG(2) << "HpackDecoder2::HandleHeaderRepresentation:\n name: " << name |
| << "\n value: " << value; |
| total_header_bytes_ += name.size() + value.size(); |
| header_seen_ = true; |
| if (handler_ == nullptr) { |
| DVLOG(3) << "HpackDecoder2::HandleHeaderRepresentation " |
| << "adding to decoded_block"; |
| decoded_block_.AppendValueOrAddHeader(name, value); |
| } else { |
| DVLOG(3) << "HpackDecoder2::HandleHeaderRepresentation " |
| << "passing to handler"; |
| DCHECK(decoded_block_.empty()); |
| handler_->OnHeader(name, value); |
| } |
| } |
| |
| } // namespace net |