package sega.a7;

import javacard.security.MessageDigest;

/**
 * Replaces the RSA private exponent. Both the modulus and the exponent must be
 * written before the new key becomes active; the update is staged in RAM.
 */
public class PrikeyExponentWrite extends AuthCommand {

    public PrikeyExponentWrite(short cmd, AppData data, MakePacket packet,
                               MessageDigest sha1, HmacSha1 hmacSha1, Crypt crypt) {
        super(cmd, (short) 302, (short) 46, AppConfig.LEVEL_AUTH,
                data, packet, sha1, hmacSha1, crypt);
    }

    public short core(byte[] data, short dataOffset, short dataLength) {
        if (m_ee_data.getSflag_ee()) {
            return AppConfig.EEPWRITE_DISABLE;
        }

        byte[] buffer = m_ee_data.getGeneralBuffer_ramD();
        if (buffer.length < AppConfig.RSA_KEY_SIZE) {
            return AppConfig.FAIL;
        }

        short decSize = decData(data,
                (short) (dataOffset + AppConfig.HEADER_SIZE),
                AppConfig.RSA_KEY_SIZE, buffer, (short) 0);
        if (decSize < AppConfig.RSA_KEY_SIZE) {
            return AppConfig.FAIL;
        }

        if (!m_ee_data.setRsaPriKeyExponent_ee(buffer, (short) 0,
                AppConfig.RSA_KEY_SIZE)) {
            return AppConfig.EEP_WRITEFAIL;
        }
        m_ee_data.activeRsaExponentUpdate_ramD();

        if (m_ee_data.getRsaModulusUpdate_ramD()) {
            byte[] modulus = m_ee_data.getRsaPriModulus_ee();
            byte[] exponent = m_ee_data.getRsaPriExponent_ee();
            if (!changeRsaKey_ee(modulus, (short) 0, (short) modulus.length,
                    exponent, (short) 0, (short) exponent.length)) {
                return AppConfig.FAIL;
            }
        }
        return AppConfig.SUCCESS;
    }
}