src/core/crypto/hkdf_sha256.cpp

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/**
 * @file
 *   This file implements HMAC-based Extract-and-Expand Key Derivation Function (HKDF) using SHA-256.
 */

#include "hkdf_sha256.hpp"

#include <string.h>

#include "common/code_utils.hpp"
#include "common/debug.hpp"
#include "common/error.hpp"
#include "openthread/platform/crypto.h"

namespace ot {
namespace Crypto {

HkdfSha256::HkdfSha256(void)
{
    mContext.mContext     = mContextStorage;
    mContext.mContextSize = sizeof(mContextStorage);
    SuccessOrAssert(otPlatCryptoHkdfInit(&mContext));
}

HkdfSha256::~HkdfSha256(void)
{
    SuccessOrAssert(otPlatCryptoHkdfDeinit(&mContext));
}

void HkdfSha256::Extract(const uint8_t *aSalt, uint16_t aSaltLength, const Key &aInputKey)
{
    SuccessOrAssert(otPlatCryptoHkdfExtract(&mContext, aSalt, aSaltLength, &aInputKey));
}

void HkdfSha256::Expand(const uint8_t *aInfo, uint16_t aInfoLength, uint8_t *aOutputKey, uint16_t aOutputKeyLength)
{
    SuccessOrAssert(otPlatCryptoHkdfExpand(&mContext, aInfo, aInfoLength, aOutputKey, aOutputKeyLength));
}

} // namespace Crypto
} // namespace ot