Source/WebCore/Modules/webauthn/fido/FidoHidMessage.cpp

// Copyright 2017 The Chromium Authors. All rights reserved.
// Copyright (C) 2018 Apple Inc. All rights reserved.
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#include "config.h"
#include "FidoHidMessage.h"

#if ENABLE(WEB_AUTHN)

#include "FidoParsingUtils.h"
#include <wtf/Optional.h>
#include <wtf/Vector.h>

namespace fido {

// static
Optional<FidoHidMessage> FidoHidMessage::create(uint32_t channelId, FidoHidDeviceCommand type, const Vector<uint8_t>& data)
{
    if (data.size() > kHidMaxMessageSize)
        return WTF::nullopt;

    switch (type) {
    case FidoHidDeviceCommand::kPing:
        break;
    case FidoHidDeviceCommand::kMsg:
    case FidoHidDeviceCommand::kCbor: {
        if (data.isEmpty())
            return WTF::nullopt;
        break;
    }

    case FidoHidDeviceCommand::kCancel:
    case FidoHidDeviceCommand::kWink: {
        if (!data.isEmpty())
            return WTF::nullopt;
        break;
    }
    case FidoHidDeviceCommand::kLock: {
        if (data.size() != 1 || data[0] > kHidMaxLockSeconds)
            return WTF::nullopt;
        break;
    }
    case FidoHidDeviceCommand::kInit: {
        if (data.size() != 8)
            return WTF::nullopt;
        break;
    }
    case FidoHidDeviceCommand::kKeepAlive:
    case FidoHidDeviceCommand::kError:
        if (data.size() != 1)
            return WTF::nullopt;
    }

    return FidoHidMessage(channelId, type, data);
}

// static
Optional<FidoHidMessage> FidoHidMessage::createFromSerializedData(const Vector<uint8_t>& serializedData)
{
    size_t remainingSize = 0;
    if (serializedData.size() > kHidPacketSize || serializedData.size() < kHidInitPacketHeaderSize)
        return WTF::nullopt;

    auto initPacket = FidoHidInitPacket::createFromSerializedData(serializedData, &remainingSize);

    if (!initPacket)
        return WTF::nullopt;

    return FidoHidMessage(WTFMove(initPacket), remainingSize);
}

bool FidoHidMessage::messageComplete() const
{
    return !m_remainingSize;
}

Vector<uint8_t> FidoHidMessage::getMessagePayload() const
{
    Vector<uint8_t> data;
    size_t dataSize = 0;
    for (const auto& packet : m_packets)
        dataSize += packet->getPacketPayload().size();
    data.reserveInitialCapacity(dataSize);

    for (const auto& packet : m_packets) {
        const auto& packet_data = packet->getPacketPayload();
        data.appendVector(packet_data);
    }

    return data;
}

Vector<uint8_t> FidoHidMessage::popNextPacket()
{
    if (m_packets.isEmpty())
        return { };

    Vector<uint8_t> data = m_packets.first()->getSerializedData();
    m_packets.removeFirst();
    return data;
}

bool FidoHidMessage::addContinuationPacket(const Vector<uint8_t>& buf)
{
    size_t remainingSize = m_remainingSize;
    auto contPacket = FidoHidContinuationPacket::createFromSerializedData(buf, &remainingSize);

    // Reject packets with a different channel id.
    if (!contPacket || m_channelId != contPacket->channelId())
        return false;

    m_remainingSize = remainingSize;
    m_packets.append(WTFMove(contPacket));
    return true;
}

size_t FidoHidMessage::numPackets() const
{
    return m_packets.size();
}

FidoHidMessage::FidoHidMessage(uint32_t channelId, FidoHidDeviceCommand type, const Vector<uint8_t>& data)
    : m_channelId(channelId)
    , m_cmd(type)
{
    uint8_t sequence = 0;

    size_t pos = data.size() > kHidInitPacketDataSize ? kHidInitPacketDataSize : data.size();
    m_packets.append(makeUnique<FidoHidInitPacket>(channelId, type, getInitPacketData(data), data.size()));
    for (; pos < data.size(); pos += kHidContinuationPacketDataSize)
        m_packets.append(makeUnique<FidoHidContinuationPacket>(channelId, sequence++, getContinuationPacketData(data, pos)));
}

FidoHidMessage::FidoHidMessage(std::unique_ptr<FidoHidInitPacket> initPacket, size_t remainingSize)
    : m_remainingSize(remainingSize)
{
    m_channelId = initPacket->channelId();
    m_cmd = initPacket->command();
    m_packets.append(WTFMove(initPacket));
}

} // namespace fido

#endif // ENABLE(WEB_AUTHN)