File content as of revision 0:33d4e66780c0:

/*******************************************************************************
* Copyright (C) 2017 Maxim Integrated Products, Inc., All Rights Reserved.
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*
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* OTHER DEALINGS IN THE SOFTWARE.
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* Products, Inc. Branding Policy.
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#include <I2C.h>
#include <wait_api.h>
#include "DS2476.hpp"

// DS2476 additional commands.
enum Command
{
    GenerateEcdsaSignature = 0x1E,
    ComputeSha2UniqueSecret = 0x55,
    ComputeSha2Hmac = 0x2D
};

DS2476::CmdResult DS2476::generateEcdsaSignature(KeyNum keyNum, Signature & signature)
{
    if (keyNum == KeyNumS)
    {
        return InvalidParameterError;
    }
    
    Buffer buffer;
    buffer.push_back(keyNum);
    CmdResult result = writeCommand(GenerateEcdsaSignature, buffer);
    if (result == Success)
    {
        wait_ms(generateEcdsaSignatureTimeMs);
        result = readResponse(buffer);
        if (result == Success)
        {
            if (buffer.size() == (1 + signature.r.size() + signature.s.size()))
            {
                result = convertResultByte(buffer[0]);
                Buffer::const_iterator begin = buffer.begin() + 1;
                Buffer::const_iterator end = begin + signature.s.size();
                std::copy(begin, end, signature.s.begin());
                begin = end;
                end = begin + signature.r.size();
                std::copy(begin, end, signature.r.begin());
            }
            else
            {
                result = CommunicationError;
            }
        }
    }
    return result;
}

DS2476::CmdResult DS2476::computeSha2UniqueSecret(SecretNum msecretNum)
{
    Buffer buffer;
    buffer.push_back(msecretNum << 4);
    CmdResult result = writeCommand(ComputeSha2UniqueSecret, buffer);
    if (result == Success)
    {
        wait_ms(sha256ComputationTimeMs);
        result = readResponse(buffer);
        if (result == Success)
        {
            if (buffer.size() == 1)
            {
                convertResultByte(buffer[0]);
            }
            else
            {
                result = CommunicationError;
            }
        }
    }
    return result;
}

DS2476::CmdResult DS2476::computeSha2Hmac(HMAC & hmac)
{
    Buffer buffer;
    CmdResult result = writeCommand(ComputeSha2Hmac, buffer);
    if (result == Success)
    {
        wait_ms(sha256ComputationTimeMs);
        result = readResponse(buffer);
        if (result == Success)
        {
            if (buffer.size() == (1 + hmac.size()))
            {
                result = convertResultByte(buffer[0]);
                std::copy(buffer.begin() + 1, buffer.end(), hmac.begin());
            }
            else
            {
                result = CommunicationError;
            }
        }
    }
    return result;
}