static void mega_aes_key_get_property(GObject *object, guint property_id, GValue *value, GParamSpec *pspec)
{
MegaAesKey *aes_key = MEGA_AES_KEY(object);
switch (property_id)
{
default:
G_OBJECT_WARN_INVALID_PROPERTY_ID(object, property_id, pspec);
}
}
/**
* mega_aes_ctr_encryptor_set_mac:
* @aes_ctr_encryptor: a #MegaAesCtrEncryptor
* @mac: a #MegaChunkedCbcMac calculator
*
* Add calculator for mac's.
*/
void mega_aes_ctr_encryptor_set_mac(MegaAesCtrEncryptor* aes_ctr_encryptor, MegaChunkedCbcMac* mac, MegaAesCtrEncryptorDirection dir)
{
MegaAesCtrEncryptorPrivate* priv;
guchar mac_iv[16];
g_return_if_fail(MEGA_IS_AES_CTR_ENCRYPTOR(aes_ctr_encryptor));
g_return_if_fail(MEGA_IS_CHUNKED_CBC_MAC(mac));
g_return_if_fail(aes_ctr_encryptor->priv->key != NULL);
priv = aes_ctr_encryptor->priv;
priv->direction = dir;
g_clear_object(&priv->mac);
priv->mac = g_object_ref(mac);
// mac iv is nonce + nonce
mega_file_key_get_nonce(priv->key, mac_iv);
mega_file_key_get_nonce(priv->key, mac_iv + 8);
mega_chunked_cbc_mac_setup(mac, MEGA_AES_KEY(priv->key), mac_iv);
}
static GConverterResult convert(GConverter *converter, const void *inbuf, gsize inbuf_size, void *outbuf, gsize outbuf_size, GConverterFlags flags, gsize *bytes_read, gsize *bytes_written, GError **error)
{
MegaAesCtrEncryptor *encryptor = MEGA_AES_CTR_ENCRYPTOR(converter);
MegaAesCtrEncryptorPrivate* priv = encryptor->priv;
guchar nonce[8];
if (!priv->key || !mega_aes_key_is_loaded(MEGA_AES_KEY(priv->key)))
{
g_set_error(error, 1, 0, "No key is set for AES-CTR decryption/encryption!");
return G_CONVERTER_ERROR;
}
if (outbuf_size < inbuf_size)
{
g_set_error(error, G_IO_ERROR, G_IO_ERROR_NO_SPACE, "No space");
return G_CONVERTER_ERROR;
}
*bytes_written = *bytes_read = 0;
mega_file_key_get_nonce(priv->key, nonce);
// if input is not aligned, align it
if (inbuf_size > 0 && priv->position % 16 != 0)
{
gsize offset = priv->position % 16;;
gsize to_align = MIN(inbuf_size, 16 - offset);
guchar align_buf[16];
if (priv->direction == MEGA_AES_CTR_ENCRYPTOR_DIRECTION_ENCRYPT && priv->mac)
mega_chunked_cbc_mac_update(priv->mac, align_buf + offset, to_align);
memcpy(align_buf + offset, inbuf, to_align);
mega_aes_key_encrypt_ctr(MEGA_AES_KEY(priv->key), nonce, priv->position / 16, align_buf, align_buf, 16);
memcpy(outbuf, align_buf + offset, to_align);
if (priv->direction == MEGA_AES_CTR_ENCRYPTOR_DIRECTION_DECRYPT)
mega_chunked_cbc_mac_update(priv->mac, outbuf, to_align);
*bytes_written = *bytes_read = to_align;
priv->position += to_align;
outbuf += to_align; inbuf += to_align;
inbuf_size -= to_align; outbuf_size -= to_align;
}
// we are aligned, and there are more data on the input
if (inbuf_size > 0)
{
if (priv->direction == MEGA_AES_CTR_ENCRYPTOR_DIRECTION_ENCRYPT && priv->mac)
mega_chunked_cbc_mac_update(priv->mac, inbuf, inbuf_size);
mega_aes_key_encrypt_ctr(MEGA_AES_KEY(priv->key), nonce, priv->position / 16, inbuf, outbuf, inbuf_size);
if (priv->direction == MEGA_AES_CTR_ENCRYPTOR_DIRECTION_DECRYPT && priv->mac)
mega_chunked_cbc_mac_update(priv->mac, outbuf, inbuf_size);
*bytes_written = *bytes_read = *bytes_read + inbuf_size;
priv->position += inbuf_size;
}
if (flags & G_CONVERTER_INPUT_AT_END)
return G_CONVERTER_FINISHED;
if (flags & G_CONVERTER_FLUSH)
return G_CONVERTER_FLUSHED;
return G_CONVERTER_CONVERTED;
}
