mirror of
https://github.com/kidfromjupiter/nearby.git
synced 2026-09-14 14:46:12 -04:00
82 lines
2.6 KiB
C++
82 lines
2.6 KiB
C++
// Copyright 2025 Google LLC
|
|
//
|
|
// Licensed under the Apache License, Version 2.0 (the "License");
|
|
// you may not use this file except in compliance with the License.
|
|
// You may obtain a copy of the License at
|
|
//
|
|
// https://www.apache.org/licenses/LICENSE-2.0
|
|
//
|
|
// Unless required by applicable law or agreed to in writing, software
|
|
// distributed under the License is distributed on an "AS IS" BASIS,
|
|
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
|
|
// See the License for the specific language governing permissions and
|
|
// limitations under the License.
|
|
|
|
#include "connections/implementation/mediums/advertisements/advertisement_util.h"
|
|
|
|
#include <cstdint>
|
|
#include <optional>
|
|
#include <string>
|
|
|
|
#include "absl/strings/string_view.h"
|
|
#include "internal/platform/byte_array.h"
|
|
#include "internal/platform/stream_reader.h"
|
|
|
|
namespace nearby::connections::advertisements {
|
|
namespace {
|
|
constexpr uint8_t kFakeEncryptionSize = 16;
|
|
constexpr absl::string_view kFakeEncryptionKey =
|
|
"\x00\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f";
|
|
} // namespace
|
|
|
|
// Should always match the protocol implementation to read device name.
|
|
// LINT.IfChange
|
|
std::optional<std::string> ReadDeviceName(const ByteArray& endpoint_info) {
|
|
StreamReader reader(&endpoint_info);
|
|
std::optional<uint8_t> version = reader.ReadBits(3);
|
|
if (!version.has_value() || *version > 1) {
|
|
return std::nullopt;
|
|
}
|
|
|
|
std::optional<uint8_t> has_device_name = reader.ReadBits(1);
|
|
if (!has_device_name.has_value() || *has_device_name == 1) {
|
|
return std::nullopt;
|
|
}
|
|
|
|
std::optional<uint8_t> device_type = reader.ReadBits(4);
|
|
if (!device_type.has_value()) {
|
|
return std::nullopt;
|
|
}
|
|
|
|
if (!reader.ReadBytes(16).has_value()) {
|
|
return std::nullopt;
|
|
}
|
|
|
|
std::optional<uint8_t> device_length = reader.ReadUint8();
|
|
if (!device_length.has_value() || *device_length == 0) {
|
|
return std::nullopt;
|
|
}
|
|
|
|
std::optional<ByteArray> device_name = reader.ReadBytes(*device_length);
|
|
if (!device_name.has_value()) {
|
|
return std::nullopt;
|
|
}
|
|
|
|
return std::string(*device_name);
|
|
}
|
|
|
|
std::string BuildEndpointInfo(const std::string& device_name) {
|
|
std::string endpoint_info;
|
|
endpoint_info.reserve(18 + device_name.size());
|
|
// VERSION | HAS_DEVICE_NAME | DEVICE_TYPE
|
|
endpoint_info.push_back(0x22);
|
|
// salt and encrypted_metadata_key
|
|
endpoint_info.append(kFakeEncryptionKey.data(), kFakeEncryptionSize);
|
|
endpoint_info.push_back(device_name.size());
|
|
endpoint_info.append(device_name);
|
|
return endpoint_info;
|
|
}
|
|
// LINT.ThenChange(//depot/google3/third_party/nearby/sharing/advertisement.cc)
|
|
|
|
} // namespace nearby::connections::advertisements
|