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 *     notice, this list of conditions and the following disclaimer in the

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 *  3. Neither the name of the copyright holder nor the

 *     names of its contributors may be used to endorse or promote products

 *     derived from this software without specific prior written permission.

 *

 *  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

 *  AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

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 */

#include <stdarg.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include "platform/nexus_core.hpp"

#include "platform/nexus_node.hpp"

namespace ot {

namespace Nexus {

class FuzzDataProvider

{

public:

    FuzzDataProvider(const uint8_t *aData, size_t aSize)

        : mData(aData)

        , mSize(aSize)

    {

    }

    void ConsumeData(void *aBuf, size_t aLength)

    {

        assert(aLength <= mSize);

        memcpy(aBuf, mData, aLength);

        mData += aLength;

        mSize -= aLength;

    }

    uint8_t *ConsumeRemainingBytes(void)

    {

        uint8_t *buf = static_cast<uint8_t *>(malloc(mSize));

        memcpy(buf, mData, mSize);

        mSize = 0;

        return buf;

    }

    uint8_t ConsumeIntegralInRange(uint8_t aMin, uint8_t aMax)

    {

        assert(aMin < aMax);

        uint16_t range = aMax - aMin;

        uint8_t  result;

        ConsumeData(&result, sizeof(result));

        result = result % (range + 1);

        return result + aMin;

    }

    size_t RemainingBytes(void) { return mSize; }

private:

    const uint8_t *mData;

    size_t         mSize;

};

extern "C" int LLVMFuzzerTestOneInput(const uint8_t *data, size_t size)

{

    FuzzDataProvider fdp(data, size);

    unsigned int seed;

    otRadioFrame frame;

    otError      error;

    if (size < sizeof(seed) + sizeof(error) + sizeof(frame))

    {

        return 0;

    }

    if (size > sizeof(seed) + sizeof(error) + sizeof(frame) + OT_RADIO_FRAME_MAX_SIZE)

    {

        return 0;

    }

    fdp.ConsumeData(&seed, sizeof(seed));

    srand(seed);

    Core nexus;

    Node &node = nexus.CreateNode();

    node.GetInstance().SetLogLevel(kLogLevelInfo);

    node.GetInstance().Get<BorderRouter::RoutingManager>().Init(/* aInfraIfIndex */ 1, /* aInfraIfIsRunning */ true);

    node.GetInstance().Get<BorderRouter::RoutingManager>().SetEnabled(true);

    node.GetInstance().Get<Srp::Server>().SetAutoEnableMode(true);

    node.GetInstance().Get<BorderRouter::RoutingManager>().SetDhcp6PdEnabled(true);

    node.GetInstance().Get<BorderRouter::RoutingManager>().SetNat64PrefixManagerEnabled(true);

    node.GetInstance().Get<Nat64::Translator>().SetEnabled(true);

    Log("---------------------------------------------------------------------------------------");

    Log("Form network");

    node.Form();

    nexus.AdvanceTime(60 * 1000);

    VerifyOrQuit(node.Get<Mle::Mle>().IsLeader());

    VerifyOrQuit(node.Get<Srp::Server>().GetState() == Srp::Server::kStateRunning);

    Log("---------------------------------------------------------------------------------------");

    Log("Fuzz");

    error = static_cast<otError>(fdp.ConsumeIntegralInRange(OT_ERROR_NONE, OT_NUM_ERRORS - 1));

    fdp.ConsumeData(&frame, sizeof(frame));

    frame.mLength = fdp.RemainingBytes();

    if (frame.mLength == 0)

    {

        frame.mPsdu = NULL;

    }

    else

    {

        frame.mPsdu = fdp.ConsumeRemainingBytes();

    }

    otPlatRadioReceiveDone(&node.GetInstance(), &frame, error);

    nexus.AdvanceTime(10 * 1000);

    if (frame.mPsdu)

    {

        free(frame.mPsdu);

    }

exit:

    return 0;

}

} // namespace Nexus

} // namespace ot