src/core/crypto/hmac_sha256.cpp

/*
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/**
 * @file
 *   This file implements HMAC SHA-256.
 */

#include "hmac_sha256.hpp"
#include "common/debug.hpp"
#include "common/error.hpp"
#include "common/message.hpp"

namespace ot {
namespace Crypto {

HmacSha256::HmacSha256(void)
{
    mContext.mContext     = mContextStorage;
    mContext.mContextSize = sizeof(mContextStorage);

    SuccessOrAssert(otPlatCryptoHmacSha256Init(&mContext));
}

HmacSha256::~HmacSha256(void)
{
    SuccessOrAssert(otPlatCryptoHmacSha256Deinit(&mContext));
}

void HmacSha256::Start(const Key &aKey)
{
    SuccessOrAssert(otPlatCryptoHmacSha256Start(&mContext, &aKey));
}

void HmacSha256::Update(const void *aBuf, uint16_t aBufLength)
{
    SuccessOrAssert(otPlatCryptoHmacSha256Update(&mContext, aBuf, aBufLength));
}

void HmacSha256::Finish(Hash &aHash)
{
    SuccessOrAssert(otPlatCryptoHmacSha256Finish(&mContext, aHash.m8, Hash::kSize));
}

void HmacSha256::Update(const Message &aMessage, uint16_t aOffset, uint16_t aLength)
{
    Message::Chunk chunk;

    aMessage.GetFirstChunk(aOffset, aLength, chunk);

    while (chunk.GetLength() > 0)
    {
        Update(chunk.GetBytes(), chunk.GetLength());
        aMessage.GetNextChunk(aLength, chunk);
    }
}

} // namespace Crypto
} // namespace ot