/*

 * 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 <http://www.gnu.org/licenses/>

 *

 */

#include "gnutls_int.h"

#include <algorithms.h>

#include "errors.h"

#include <x509/common.h>

#include <pk.h>

/* Supported ECC curves

 */

static const gnutls_group_entry_st supported_groups[] = {

	{

	 .name = "SECP192R1",

	 .id = GNUTLS_GROUP_SECP192R1,

	 .curve = GNUTLS_ECC_CURVE_SECP192R1,

	 .tls_id = 19,

	 .pk = GNUTLS_PK_ECDSA,

	},

	{

	 .name = "SECP224R1",

	 .id = GNUTLS_GROUP_SECP224R1,

	 .curve = GNUTLS_ECC_CURVE_SECP224R1,

	 .tls_id = 21,

	 .pk = GNUTLS_PK_ECDSA,

	},

	{

	 .name = "SECP256R1",

	 .id = GNUTLS_GROUP_SECP256R1,

	 .curve = GNUTLS_ECC_CURVE_SECP256R1,

	 .tls_id = 23,

	 .pk = GNUTLS_PK_ECDSA,

	},

	{

	 .name = "SECP384R1",

	 .id = GNUTLS_GROUP_SECP384R1,

	 .curve = GNUTLS_ECC_CURVE_SECP384R1,

	 .tls_id = 24,

	 .pk = GNUTLS_PK_ECDSA,

	},

	{

	 .name = "SECP521R1",

	 .id = GNUTLS_GROUP_SECP521R1,

	 .curve = GNUTLS_ECC_CURVE_SECP521R1,

	 .tls_id = 25,

	 .pk = GNUTLS_PK_ECDSA,

	},

	{

	 .name = "X25519",

	 .id = GNUTLS_GROUP_X25519,

	 .curve = GNUTLS_ECC_CURVE_X25519,

	 .tls_id = 29,

	 .pk = GNUTLS_PK_ECDH_X25519

	},

#ifdef ENABLE_DHE

	{

	 .name = "FFDHE2048",

	 .id = GNUTLS_GROUP_FFDHE2048,

	 .generator = &gnutls_ffdhe_2048_group_generator,

	 .prime = &gnutls_ffdhe_2048_group_prime,

	 .q_bits = &gnutls_ffdhe_2048_key_bits,

	 .pk = GNUTLS_PK_DH,

	 .tls_id = 0x100

	},

	{

	 .name = "FFDHE3072",

	 .id = GNUTLS_GROUP_FFDHE3072,

	 .generator = &gnutls_ffdhe_3072_group_generator,

	 .prime = &gnutls_ffdhe_3072_group_prime,

	 .q_bits = &gnutls_ffdhe_3072_key_bits,

	 .pk = GNUTLS_PK_DH,

	 .tls_id = 0x101

	},

	{

	 .name = "FFDHE4096",

	 .id = GNUTLS_GROUP_FFDHE4096,

	 .generator = &gnutls_ffdhe_4096_group_generator,

	 .prime = &gnutls_ffdhe_4096_group_prime,

	 .q_bits = &gnutls_ffdhe_4096_key_bits,

	 .pk = GNUTLS_PK_DH,

	 .tls_id = 0x102

	},

	{

	 .name = "FFDHE8192",

	 .id = GNUTLS_GROUP_FFDHE8192,

	 .generator = &gnutls_ffdhe_8192_group_generator,

	 .prime = &gnutls_ffdhe_8192_group_prime,

	 .q_bits = &gnutls_ffdhe_8192_key_bits,

	 .pk = GNUTLS_PK_DH,

	 .tls_id = 0x104

	},

#endif

	{0, 0, 0}

};

#define GNUTLS_GROUP_LOOP(b) \

	{ const gnutls_group_entry_st *p; \

		for(p = supported_groups; p->name != NULL; p++) { b ; } }

/* Returns the TLS id of the given curve

 */

const gnutls_group_entry_st * _gnutls_tls_id_to_group(unsigned num)

{

	GNUTLS_GROUP_LOOP(

		if (p->tls_id == num &&

		    (p->curve == 0 || _gnutls_pk_curve_exists(p->curve))) {

			return p;

		}

	);

	return NULL;

}

const gnutls_group_entry_st * _gnutls_id_to_group(unsigned id)

{

	if (id == 0)

		return NULL;

	GNUTLS_GROUP_LOOP(

		if (p->id == id &&

		    (p->curve == 0 || _gnutls_pk_curve_exists(p->curve))) {

			return p;

		}

	);

	return NULL;

}

/**

 * gnutls_group_list:

 *

 * Get the list of supported elliptic curves.

 *

 * This function is not thread safe.

 *

 * Returns: Return a (0)-terminated list of #gnutls_group_t

 *   integers indicating the available groups.

 *

 * Since: 3.6.0

 **/

const gnutls_group_t *gnutls_group_list(void)

{

	static gnutls_group_t groups[MAX_ALGOS] = { 0 };

	if (groups[0] == 0) {

		int i = 0;

		GNUTLS_GROUP_LOOP(

			if (p->curve == 0 || _gnutls_pk_curve_exists(p->curve)) 

				groups[i++] = p->id;

		);

		groups[i++] = 0;

	}

	return groups;

}

/**

 * gnutls_group_get_id:

 * @name: is a group name

 *

 * The names are compared in a case insensitive way.

 *

 * Returns: return a #gnutls_group_t value corresponding to

 *   the specified group, or %GNUTLS_GROUP_INVALID on error.

 *

 * Since: 3.6.0

 **/

gnutls_group_t gnutls_group_get_id(const char *name)

{

	gnutls_group_t ret = GNUTLS_GROUP_INVALID;

	GNUTLS_GROUP_LOOP(

		if (strcasecmp(p->name, name) == 0 && (

		    p->curve == 0 ||_gnutls_pk_curve_exists(p->curve))) {

			ret = p->id;

			break;

		}

	);

	return ret;

}

/**

 * gnutls_group_get_name:

 * @group: is an element from %gnutls_group_t

 *

 * Convert a #gnutls_group_t value to a string.

 *

 * Returns: a string that contains the name of the specified

 *   group or %NULL.

 *

 * Since: 3.6.0

 **/

const char *gnutls_group_get_name(gnutls_group_t group)

{

	GNUTLS_GROUP_LOOP(

		if (p->id == group) {

			return p->name;

		}

	);

	return NULL;

}