src/core/meshcop/meshcop_tlvs.cpp

/*
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 *     notice, this list of conditions and the following disclaimer in the
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 *     derived from this software without specific prior written permission.
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/**
 * @file
 *   This file implements MechCop TLV helper functions.
 */

#include "meshcop_tlvs.hpp"

#include "common/debug.hpp"

namespace ot {
namespace MeshCoP {

bool Tlv::IsValid(const Tlv &aTlv)
{
    bool rval = true;

    switch (aTlv.GetType())
    {
    case Tlv::kChannel:
        rval = static_cast<const ChannelTlv &>(aTlv).IsValid();
        break;

    case Tlv::kPanId:
        rval = static_cast<const PanIdTlv &>(aTlv).IsValid();
        break;

    case Tlv::kExtendedPanId:
        rval = static_cast<const ExtendedPanIdTlv &>(aTlv).IsValid();
        break;

    case Tlv::kNetworkName:
        rval = static_cast<const NetworkNameTlv &>(aTlv).IsValid();
        break;

    case Tlv::kNetworkMasterKey:
        rval = static_cast<const NetworkMasterKeyTlv &>(aTlv).IsValid();
        break;

    case Tlv::kPSKc:
        rval = static_cast<const PSKcTlv &>(aTlv).IsValid();
        break;

    case Tlv::kMeshLocalPrefix:
        rval = static_cast<const MeshLocalPrefixTlv &>(aTlv).IsValid();
        break;

    case Tlv::kSecurityPolicy:
        rval = static_cast<const SecurityPolicyTlv &>(aTlv).IsValid();
        break;

    default:
        break;
    }

    return rval;
}

bool SteeringDataTlv::IsCleared(void) const
{
    bool rval = true;

    for (uint8_t i = 0; i < GetLength(); i++)
    {
        if (mSteeringData[i] != 0)
        {
            rval = false;
            break;
        }
    }

    return rval;
}

void SteeringDataTlv::ComputeBloomFilter(const otExtAddress &aJoinerId)
{
    Crc16 ccitt(Crc16::kCcitt);
    Crc16 ansi(Crc16::kAnsi);

    for (size_t j = 0; j < sizeof(otExtAddress); j++)
    {
        uint8_t byte = aJoinerId.m8[j];
        ccitt.Update(byte);
        ansi.Update(byte);
    }

    SetBit(ccitt.Get() % GetNumBits());
    SetBit(ansi.Get() % GetNumBits());
}

bool ChannelTlv::IsValid(void) const
{
    bool ret = false;

    VerifyOrExit(GetLength() == sizeof(*this) - sizeof(Tlv));
    VerifyOrExit(mChannelPage <= OT_RADIO_CHANNEL_PAGE_MAX);
    VerifyOrExit((1U << mChannelPage) & Radio::kSupportedChannelPages);
    VerifyOrExit(Radio::kChannelMin <= GetChannel() && GetChannel() <= Radio::kChannelMax);
    ret = true;

exit:
    return ret;
}

void ChannelTlv::SetChannel(uint16_t aChannel)
{
    uint8_t channelPage = OT_RADIO_CHANNEL_PAGE_0;

#if OPENTHREAD_CONFIG_RADIO_2P4GHZ_OQPSK_SUPPORT
    if ((OT_RADIO_2P4GHZ_OQPSK_CHANNEL_MIN <= aChannel) && (aChannel <= OT_RADIO_2P4GHZ_OQPSK_CHANNEL_MAX))
    {
        channelPage = OT_RADIO_CHANNEL_PAGE_0;
    }
#endif

#if OPENTHREAD_CONFIG_RADIO_915MHZ_OQPSK_SUPPORT
    if ((OT_RADIO_915MHZ_OQPSK_CHANNEL_MIN <= aChannel) && (aChannel <= OT_RADIO_915MHZ_OQPSK_CHANNEL_MAX))
    {
        channelPage = OT_RADIO_CHANNEL_PAGE_2;
    }
#endif

    SetChannelPage(channelPage);
    mChannel = HostSwap16(aChannel);
}

const ChannelMaskEntryBase *ChannelMaskBaseTlv::GetFirstEntry(void) const
{
    const ChannelMaskEntryBase *entry = NULL;

    VerifyOrExit(GetLength() >= sizeof(ChannelMaskEntryBase));

    entry = reinterpret_cast<const ChannelMaskEntryBase *>(GetValue());
    VerifyOrExit(GetLength() >= entry->GetEntrySize(), entry = NULL);

exit:
    return entry;
}

ChannelMaskEntryBase *ChannelMaskBaseTlv::GetFirstEntry(void)
{
    return const_cast<ChannelMaskEntryBase *>(static_cast<const ChannelMaskBaseTlv *>(this)->GetFirstEntry());
}

void ChannelMaskTlv::SetChannelMask(uint32_t aChannelMask)
{
    uint8_t           length = 0;
    ChannelMaskEntry *entry;

    entry = static_cast<ChannelMaskEntry *>(GetFirstEntry());

#if OPENTHREAD_CONFIG_RADIO_915MHZ_OQPSK_SUPPORT
    if (aChannelMask & OT_RADIO_915MHZ_OQPSK_CHANNEL_MASK)
    {
        assert(entry != NULL);
        entry->Init();
        entry->SetChannelPage(OT_RADIO_CHANNEL_PAGE_2);
        entry->SetMask(aChannelMask & OT_RADIO_915MHZ_OQPSK_CHANNEL_MASK);

        length += sizeof(MeshCoP::ChannelMaskEntry);

        entry = static_cast<MeshCoP::ChannelMaskEntry *>(entry->GetNext());
    }
#endif

#if OPENTHREAD_CONFIG_RADIO_2P4GHZ_OQPSK_SUPPORT
    if (aChannelMask & OT_RADIO_2P4GHZ_OQPSK_CHANNEL_MASK)
    {
        assert(entry != NULL);
        entry->Init();
        entry->SetChannelPage(OT_RADIO_CHANNEL_PAGE_0);
        entry->SetMask(aChannelMask & OT_RADIO_2P4GHZ_OQPSK_CHANNEL_MASK);

        length += sizeof(MeshCoP::ChannelMaskEntry);
    }
#endif

    SetLength(length);
}

uint32_t ChannelMaskTlv::GetChannelMask(void) const
{
    uint32_t                mask = 0;
    const ChannelMaskEntry *cur  = static_cast<const ChannelMaskEntry *>(GetFirstEntry());
    const ChannelMaskEntry *end  = reinterpret_cast<const ChannelMaskEntry *>(GetValue() + GetLength());

    for (; cur < end; cur = static_cast<const ChannelMaskEntry *>(cur->GetNext()))
    {
        VerifyOrExit((cur + 1) <= end && cur->GetNext() <= end);

#if OPENTHREAD_CONFIG_RADIO_915MHZ_OQPSK_SUPPORT
        if (cur->GetChannelPage() == OT_RADIO_CHANNEL_PAGE_2)
        {
            mask |= cur->GetMask() & OT_RADIO_915MHZ_OQPSK_CHANNEL_MASK;
        }
#endif

#if OPENTHREAD_CONFIG_RADIO_2P4GHZ_OQPSK_SUPPORT
        if (cur->GetChannelPage() == OT_RADIO_CHANNEL_PAGE_0)
        {
            mask |= cur->GetMask() & OT_RADIO_2P4GHZ_OQPSK_CHANNEL_MASK;
        }
#endif
    }

exit:
    return mask;
}

uint32_t ChannelMaskTlv::GetChannelMask(const Message &aMessage)
{
    uint32_t mask = 0;
    uint16_t offset;
    uint16_t end;

    SuccessOrExit(GetValueOffset(aMessage, kChannelMask, offset, end));
    end += offset;

    while (offset + sizeof(ChannelMaskEntryBase) <= end)
    {
        ChannelMaskEntry entry;

        aMessage.Read(offset, sizeof(ChannelMaskEntryBase), &entry);
        VerifyOrExit(offset + entry.GetEntrySize() <= end);

        switch (entry.GetChannelPage())
        {
#if OPENTHREAD_CONFIG_RADIO_2P4GHZ_OQPSK_SUPPORT
        case OT_RADIO_CHANNEL_PAGE_0:
            aMessage.Read(offset, sizeof(entry), &entry);
            mask |= entry.GetMask() & OT_RADIO_2P4GHZ_OQPSK_CHANNEL_MASK;
            break;
#endif

#if OPENTHREAD_CONFIG_RADIO_915MHZ_OQPSK_SUPPORT
        case OT_RADIO_CHANNEL_PAGE_2:
            aMessage.Read(offset, sizeof(entry), &entry);
            mask |= entry.GetMask() & OT_RADIO_915MHZ_OQPSK_CHANNEL_MASK;
            break;
#endif
        }

        offset += entry.GetEntrySize();
    }

exit:
    return mask;
}

} // namespace MeshCoP
} // namespace ot