source: chevmsgr/trunk/crypto.cpp@ 13

#include "crypto.h"

#include "KISA_SHA256.h"

#define ARIA_BLOCKSIZE  16

crypto::crypto()
{
}

void crypto::setKey(cf::bin & key)
{
    ::CHEV_ARIA_Initialize(&info, CHEV_ARIA_256, key.buffer(), key.size());
}

cf::bin crypto::sha256(cf::bin & input)
{
    cf::bin out;

    out.resize(SHA256_DIGEST_VALUELEN);

    ::SHA256_Encrpyt(input.buffer(), input.size(), out.buffer());

    return out;
}

cf::bin crypto::encrypt(cf::bin & input)
{
    cf::bin plain;
    cf::bin out;
    int outSize;

    plain = input + getPaddingBytes(ARIA_BLOCKSIZE, input.size());

    out.resize(plain.size());

    ::CHEV_ARIA_Encrypt(&info, plain.buffer(), plain.size(), out.buffer(), &outSize);

    return out;
}

cf::bin crypto::decrypt(cf::bin & input)
{
    int plainSize;
    int paddingSize;
    cf::bin out;
    int outSize;

    out.resize(input.size());

    ::CHEV_ARIA_Decrypt(&info, input.buffer(), input.size(), out.buffer(), &outSize);

    paddingSize = out[outSize - 1];

    plainSize = outSize - paddingSize;
    out.resize(plainSize);

    return out;
}

cf::bin crypto::getPaddingBytes(int blockSize, int inputSize)
{
    int paddingSize = blockSize - (inputSize % blockSize);
    cf::bin result;

    result.resize(paddingSize);

    memset(result.buffer(), paddingSize, paddingSize);

    return result;
}