/*
 * Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005 Free Software Foundation
 *
 * Author: Nikos Mavroyanopoulos
 *
 * This file is part of GNUTLS.
 *
 * The GNUTLS library 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 library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
 * USA
 *
 */

/* This file contains the Anonymous Diffie Hellman key exchange part of
 * the anonymous authentication. The functions here are used in the
 * handshake.
 */

#include <gnutls_int.h>

#ifdef ENABLE_ANON

#include "gnutls_auth_int.h"
#include "gnutls_errors.h"
#include "gnutls_dh.h"
#include "auth_anon.h"
#include "gnutls_num.h"
#include "gnutls_mpi.h"
#include <gnutls_state.h>
#include <auth_dh_common.h>

static int gen_anon_server_kx(gnutls_session_t, opaque **);
static int proc_anon_client_kx(gnutls_session_t, opaque *, size_t);
static int proc_anon_server_kx(gnutls_session_t, opaque *, size_t);

const mod_auth_st anon_auth_struct = {
    "ANON",
    NULL,
    NULL,
    gen_anon_server_kx,
    _gnutls_gen_dh_common_client_kx,	/* this can be shared */
    NULL,
    NULL,

    NULL,
    NULL,			/* certificate */
    proc_anon_server_kx,
    proc_anon_client_kx,
    NULL,
    NULL
};

static int gen_anon_server_kx(gnutls_session_t session, opaque ** data)
{
    mpi_t g, p;
    const mpi_t *mpis;
    int ret;
    gnutls_dh_params_t dh_params;
    gnutls_anon_server_credentials_t cred;

    cred = (gnutls_anon_server_credentials_t)
        _gnutls_get_cred(session->key, GNUTLS_CRD_ANON, NULL);
    if (cred == NULL) {
	gnutls_assert();
	return GNUTLS_E_INSUFFICIENT_CREDENTIALS;
    }

    dh_params = _gnutls_anon_get_dh_params(cred, session);
    mpis = _gnutls_get_dh_params(dh_params);
    if (mpis == NULL) {
	gnutls_assert();
	return GNUTLS_E_NO_TEMPORARY_DH_PARAMS;
    }

    p = mpis[0];
    g = mpis[1];

    if ((ret =
	 _gnutls_auth_info_set(session, GNUTLS_CRD_ANON,
			       sizeof(anon_server_auth_info_st), 1)) < 0) {
	gnutls_assert();
	return ret;
    }

    _gnutls_dh_set_group(session, g, p);

    ret = _gnutls_dh_common_print_server_kx(session, g, p, data);
    if (ret < 0) {
	gnutls_assert();
    }

    return ret;
}


static int proc_anon_client_kx(gnutls_session_t session, opaque * data,
			       size_t _data_size)
{
    gnutls_anon_server_credentials_t cred;
    int bits;
    int ret;
    mpi_t p, g;
    gnutls_dh_params_t dh_params;
    const mpi_t *mpis;

    bits = _gnutls_dh_get_allowed_prime_bits(session);

    cred = (gnutls_anon_server_credentials_t)
        _gnutls_get_cred(session->key, GNUTLS_CRD_ANON, NULL);
    if (cred == NULL) {
	gnutls_assert();
	return GNUTLS_E_INSUFFICIENT_CREDENTIALS;
    }

    dh_params = _gnutls_anon_get_dh_params(cred, session);
    mpis = _gnutls_get_dh_params(dh_params);
    if (mpis == NULL) {
	gnutls_assert();
	return GNUTLS_E_NO_TEMPORARY_DH_PARAMS;
    }

    p = mpis[0];
    g = mpis[1];

    ret =
	_gnutls_proc_dh_common_client_kx(session, data, _data_size, g, p);

    return ret;

}

int proc_anon_server_kx(gnutls_session_t session, opaque * data,
			size_t _data_size)
{

    int ret;

    /* set auth_info */
    if ((ret =
	 _gnutls_auth_info_set(session, GNUTLS_CRD_ANON,
			       sizeof(anon_client_auth_info_st), 1)) < 0) {
	gnutls_assert();
	return ret;
    }

    ret = _gnutls_proc_dh_common_server_kx(session, data, _data_size);
    if (ret < 0) {
	gnutls_assert();
	return ret;
    }

    return 0;
}

#endif				/* ENABLE_ANON */