/*

 * Copyright (C) 2017 Red Hat, Inc.

 *

 * Author: Nikos Mavrogiannopoulos

 *

 * This file is part of GnuTLS.

 *

 * The GnuTLS is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public License

 * as published by the Free Software Foundation; either version 2.1 of

 * the License, or (at your option) any later version.

 *

 * This library is distributed in the hope that it will be useful, but

 * WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public License

 * along with this program.  If not, see <https://www.gnu.org/licenses/>

 *

 */

/* Internal API functions to be used by extension handlers.

 */

#include "gnutls_int.h"

#include "hello_ext.h"

#include "hello_ext_lib.h"

void _gnutls_hello_ext_default_deinit(gnutls_ext_priv_data_t priv)

{

	gnutls_free(priv);

}

/* When this is used, the deinitialization function must be set to default:

 * _gnutls_hello_ext_default_deinit.

 *

 * This also prevents and errors on duplicate entries.

 */

int

_gnutls_hello_ext_set_datum(gnutls_session_t session,

			    extensions_t id, const gnutls_datum_t *data)

{

	gnutls_ext_priv_data_t epriv;

	if (_gnutls_hello_ext_get_priv(session, id, &epriv) >= 0)

		return gnutls_assert_val(GNUTLS_E_RECEIVED_ILLEGAL_PARAMETER);

	if (data->size >= UINT16_MAX)

		return gnutls_assert_val(GNUTLS_E_RECEIVED_ILLEGAL_PARAMETER);

	epriv = gnutls_malloc(data->size+2);

	if (epriv == NULL)

		return gnutls_assert_val(GNUTLS_E_MEMORY_ERROR);

	_gnutls_write_uint16(data->size, epriv);

	memcpy(((uint8_t*)epriv)+2, data->data, data->size);

	_gnutls_hello_ext_set_priv(session, id, epriv);

	return 0;

}

int

_gnutls_hello_ext_get_datum(gnutls_session_t session,

			    extensions_t id, gnutls_datum_t *data /* constant contents */)

{

	gnutls_ext_priv_data_t epriv;

	int ret;

	ret = _gnutls_hello_ext_get_priv(session, id, &epriv);

	if (ret < 0 || epriv == NULL)

		return GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE;

	data->size = _gnutls_read_uint16(epriv);

	data->data = ((uint8_t*)epriv)+2;

	return 0;

}

int

_gnutls_hello_ext_get_resumed_datum(gnutls_session_t session,

				    extensions_t id, gnutls_datum_t *data /* constant contents */)

{

	gnutls_ext_priv_data_t epriv;

	int ret;

	ret = _gnutls_hello_ext_get_resumed_priv(session, id, &epriv);

	if (ret < 0 || epriv == NULL)

		return GNUTLS_E_REQUESTED_DATA_NOT_AVAILABLE;

	data->size = _gnutls_read_uint16(epriv);

	data->data = ((uint8_t*)epriv)+2;

	return 0;

}

int

_gnutls_hello_ext_default_pack(gnutls_ext_priv_data_t epriv, gnutls_buffer_st *ps)

{

	size_t size;

	size = _gnutls_read_uint16(epriv);

	return _gnutls_buffer_append_data(ps, epriv, size+2);

}

int

_gnutls_hello_ext_default_unpack(gnutls_buffer_st *ps, gnutls_ext_priv_data_t *epriv)

{

	gnutls_datum_t data;

	uint8_t *store;

	int ret;

	ret = _gnutls_buffer_pop_datum_prefix16(ps, &data);

	if (ret < 0)

		return gnutls_assert_val(ret);

	store = gnutls_calloc(1, data.size+2);

	if (store == NULL)

		return gnutls_assert_val(GNUTLS_E_MEMORY_ERROR);

	_gnutls_write_uint16(data.size, store);

	memcpy(store+2, data.data, data.size);

	*epriv = store;

	return 0;

}