src/core/api/crypto_api.cpp

/*
 *  Copyright (c) 2016, The OpenThread Authors.
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 *
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 *  modification, are permitted provided that the following conditions are met:
 *  1. Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 *  2. Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution.
 *  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
 *  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 *  ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 *  LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
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 *  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *  POSSIBILITY OF SUCH DAMAGE.
 */

/**
 * @file
 *   This file implements the OpenThread Crypto API.
 */

#include <openthread/config.h>
#include <openthread/crypto.h>

#include "common/code_utils.hpp"
#include "common/debug.hpp"
#include "crypto/aes_ccm.hpp"
#include "crypto/hmac_sha256.hpp"

using namespace ot::Crypto;

void otCryptoHmacSha256(
    const uint8_t *aKey, uint16_t aKeyLength,
    const uint8_t *aBuf, uint16_t aBufLength,
    uint8_t *aHash)
{
    HmacSha256 hmac;

    assert((aKey != NULL) && (aBuf != NULL) && (aHash != NULL));

    hmac.Start(aKey, aKeyLength);
    hmac.Update(aBuf, aBufLength);
    hmac.Finish(aHash);
}

void otCryptoAesCcm(
    const uint8_t *aKey, uint16_t aKeyLength,
    uint8_t aTagLength,
    const void *aNonce, uint8_t aNonceLength,
    const void *aHeader, uint32_t aHeaderLength,
    void *aPlainText, void *aCipherText, uint32_t aLength, bool aEncrypt,
    void *aTag)
{
    AesCcm aesCcm;
    uint8_t tagLength;

    assert((aKey != NULL) && (aNonce != NULL) && (aPlainText != NULL) && (aCipherText != NULL) && (aTag != NULL));

    SuccessOrExit(aesCcm.SetKey(aKey, aKeyLength));
    aesCcm.Init(aHeaderLength, aLength, aTagLength, aNonce, aNonceLength);

    if (aHeaderLength != 0)
    {
        assert(aHeader != NULL);
        aesCcm.Header(aHeader, aHeaderLength);
    }

    aesCcm.Payload(aPlainText, aCipherText, aLength, aEncrypt);
    aesCcm.Finalize(aTag, &tagLength);

    assert(aTagLength == tagLength);

exit:
    return;
}