Migrate weave-related classes from proximity_auth/ble to cryptauth/ble.

components/proximity_auth/ble/bluetooth_low_energy_weave_packet_generator.cc

-// 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 "components/proximity_auth/ble/bluetooth_low_energy_weave_packet_generator.h"
-
-#ifdef OS_WIN
-#include <winsock2.h>
-#else
-#include <netinet/in.h>
-#endif
-
-#include <string.h>
-
-#include <algorithm>
-
-#include "base/logging.h"
-
-namespace proximity_auth {
-namespace weave {
-
-// static.
-std::shared_ptr<BluetoothLowEnergyWeavePacketGenerator::Factory>
-    BluetoothLowEnergyWeavePacketGenerator::Factory::factory_instance_ =
-        nullptr;
-
-// static.
-std::unique_ptr<BluetoothLowEnergyWeavePacketGenerator>
-BluetoothLowEnergyWeavePacketGenerator::Factory::NewInstance() {
-  if (!factory_instance_) {
-    factory_instance_.reset(new Factory());
-  }
-  return factory_instance_->BuildInstance();
-}
-
-// static.
-void BluetoothLowEnergyWeavePacketGenerator::Factory::SetInstanceForTesting(
-    std::shared_ptr<Factory> factory) {
-  factory_instance_ = factory;
-}
-
-std::unique_ptr<BluetoothLowEnergyWeavePacketGenerator>
-BluetoothLowEnergyWeavePacketGenerator::Factory::BuildInstance() {
-  return std::unique_ptr<BluetoothLowEnergyWeavePacketGenerator>(
-      new BluetoothLowEnergyWeavePacketGenerator());
-}
-
-BluetoothLowEnergyWeavePacketGenerator::BluetoothLowEnergyWeavePacketGenerator()
-    : max_packet_size_(kDefaultMaxPacketSize), next_packet_counter_(0) {}
-
-Packet BluetoothLowEnergyWeavePacketGenerator::CreateConnectionRequest() {
-  Packet packet(kMinConnectionRequestSize, 0);
-
-  SetPacketTypeBit(PacketType::CONTROL, &packet);
-  // Since it only make sense for connection request to be the 0th packet,
-  // resets the packet counter.
-  next_packet_counter_ = 1;
-  SetControlCommand(ControlCommand::CONNECTION_REQUEST, &packet);
-  SetShortField(1, kWeaveVersion, &packet);
-  SetShortField(3, kWeaveVersion, &packet);
-  SetShortField(5, kSelectMaxPacketSize, &packet);
-
-  return packet;
-}
-
-Packet BluetoothLowEnergyWeavePacketGenerator::CreateConnectionResponse() {
-  Packet packet(kMinConnectionResponseSize, 0);
-
-  SetPacketTypeBit(PacketType::CONTROL, &packet);
-  // Since it only make sense for connection response to be the 0th packet,
-  // resets the next packet counter.
-  next_packet_counter_ = 1;
-  SetControlCommand(ControlCommand::CONNECTION_RESPONSE, &packet);
-  SetShortField(1, kWeaveVersion, &packet);
-  SetShortField(3, max_packet_size_, &packet);
-
-  return packet;
-}
-
-Packet BluetoothLowEnergyWeavePacketGenerator::CreateConnectionClose(
-    ReasonForClose reason_for_close) {
-  Packet packet(kMaxConnectionCloseSize, 0);
-
-  SetPacketTypeBit(PacketType::CONTROL, &packet);
-  SetPacketCounter(&packet);
-  SetControlCommand(ControlCommand::CONNECTION_CLOSE, &packet);
-  SetShortField(1, reason_for_close, &packet);
-
-  return packet;
-}
-
-void BluetoothLowEnergyWeavePacketGenerator::SetMaxPacketSize(uint16_t size) {
-  DCHECK(size >= kDefaultMaxPacketSize);
-  max_packet_size_ = size;
-}
-
-std::vector<Packet> BluetoothLowEnergyWeavePacketGenerator::EncodeDataMessage(
-    std::string message) {
-  DCHECK(!message.empty());
-
-  // The first byte of a packet is used by the uWeave protocol,
-  // hence the payload is 1 byte smaller than the packet size.
-  uint32_t packet_payload_size = max_packet_size_ - 1;
-
-  uint32_t message_length = message.length();
-  // (packet_payload_size - 1) is used to enforce rounding up.
-  uint32_t num_packets =
-      (message_length + (packet_payload_size - 1)) / packet_payload_size;
-
-  std::vector<Packet> weave_message(num_packets);
-
-  const char* byte_message = message.c_str();
-
-  for (uint32_t i = 0; i < num_packets; ++i) {
-    Packet* packet = &weave_message[i];
-    uint32_t begin = packet_payload_size * i;
-    uint32_t end = std::min(begin + packet_payload_size, message_length);
-
-    packet->push_back(0);
-
-    SetPacketTypeBit(PacketType::DATA, packet);
-    SetPacketCounter(packet);
-
-    for (uint32_t j = begin; j < end; ++j) {
-      packet->push_back(byte_message[j]);
-    }
-  }
-
-  // Guaranteed to have at least one packet since message is not empty.
-  SetDataFirstBit(&weave_message[0]);
-  SetDataLastBit(&weave_message[num_packets - 1]);
-
-  return weave_message;
-}
-
-void BluetoothLowEnergyWeavePacketGenerator::SetShortField(uint32_t byte_offset,
-                                                           uint16_t val,
-                                                           Packet* packet) {
-  DCHECK(packet);
-  DCHECK_LT(byte_offset, packet->size());
-  DCHECK_LT(byte_offset + 1, packet->size());
-
-  uint16_t network_val = htons(val);
-  uint8_t* network_val_ptr = reinterpret_cast<uint8_t*>(&network_val);
-
-  packet->at(byte_offset) = network_val_ptr[0];
-  packet->at(byte_offset + 1) = network_val_ptr[1];
-}
-
-void BluetoothLowEnergyWeavePacketGenerator::SetPacketTypeBit(PacketType type,
-                                                              Packet* packet) {
-  DCHECK(packet);
-  DCHECK(!packet->empty());
-
-  // Type bit is the highest bit of the first byte of the packet.
-  // So clear the highest bit and set it according to val.
-  packet->at(0) = (packet->at(0) & 0x7F) | (type << 7);
-}
-
-void BluetoothLowEnergyWeavePacketGenerator::SetControlCommand(
-    ControlCommand command,
-    Packet* packet) {
-  DCHECK(packet);
-  DCHECK(!packet->empty());
-
-  // Control Command is the lower 4 bits of the packet's first byte.
-  // So clear the lower 4 bites and set it according to val.
-  packet->at(0) = (packet->at(0) & 0xF0) | command;
-}
-
-void BluetoothLowEnergyWeavePacketGenerator::SetPacketCounter(Packet* packet) {
-  DCHECK(packet);
-  DCHECK(!packet->empty());
-  uint8_t counter = next_packet_counter_ % kMaxPacketCounter;
-
-  // Packet counter is the bits 4, 5, and 6 of the packet's first byte.
-  // So clear those bits and set them according to current packet counter
-  // modular max packet counter.
-  packet->at(0) = (packet->at(0) & 0x8F) | (counter << 4);
-  next_packet_counter_++;
-}
-
-void BluetoothLowEnergyWeavePacketGenerator::SetDataFirstBit(Packet* packet) {
-  DCHECK(packet);
-  DCHECK(!packet->empty());
-
-  // First bit is bit 3 of the packet's first byte and set it to 1.
-  packet->at(0) = packet->at(0) | (1 << 3);
-}
-
-void BluetoothLowEnergyWeavePacketGenerator::SetDataLastBit(Packet* packet) {
-  DCHECK(packet);
-  DCHECK(!packet->empty());
-
-  // Last bit is the bit 2 of the packet's first byte and set it to 1.
-  packet->at(0) = packet->at(0) | (1 << 2);
-}
-
-}  // namespace weave
-
-}  // namespace proximity_auth