/*

 * This file is part of the SSH Library

 *

 * Copyright (c) 2009 by Aris Adamantiadis

 *

 * This 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

 */

#ifndef DH_H_

#define DH_H_

#include "config.h"

#include "libssh/crypto.h"

struct dh_ctx;

#define DH_CLIENT_KEYPAIR 0

#define DH_SERVER_KEYPAIR 1

/* functions implemented by crypto backends */

int ssh_dh_init_common(struct ssh_crypto_struct *crypto);

void ssh_dh_cleanup(struct ssh_crypto_struct *crypto);

int ssh_dh_get_parameters(struct dh_ctx *ctx,

                          const_bignum *modulus, const_bignum *generator);

int ssh_dh_set_parameters(struct dh_ctx *ctx,

                          const bignum modulus, const bignum generator);

int ssh_dh_keypair_gen_keys(struct dh_ctx *ctx, int peer);

int ssh_dh_keypair_get_keys(struct dh_ctx *ctx, int peer,

                            const_bignum *priv, const_bignum *pub);

int ssh_dh_keypair_set_keys(struct dh_ctx *ctx, int peer,

                            const bignum priv, const bignum pub);

int ssh_dh_compute_shared_secret(struct dh_ctx *ctx, int local, int remote,

                                 bignum *dest);

void ssh_dh_debug_crypto(struct ssh_crypto_struct *c);

/* common functions */

int ssh_dh_init(void);

void ssh_dh_finalize(void);

int ssh_dh_import_next_pubkey_blob(ssh_session session,

                                   ssh_string pubkey_blob);

ssh_key ssh_dh_get_current_server_publickey(ssh_session session);

int ssh_dh_get_current_server_publickey_blob(ssh_session session,

                                             ssh_string *pubkey_blob);

ssh_key ssh_dh_get_next_server_publickey(ssh_session session);

int ssh_dh_get_next_server_publickey_blob(ssh_session session,

                                          ssh_string *pubkey_blob);

int ssh_client_dh_init(ssh_session session);

#ifdef WITH_SERVER

void ssh_server_dh_init(ssh_session session);

#endif /* WITH_SERVER */

int ssh_server_dh_process_init(ssh_session session, ssh_buffer packet);

int ssh_fallback_group(uint32_t pmax, bignum *p, bignum *g);

bool ssh_dh_is_known_group(bignum modulus, bignum generator);

#endif /* DH_H_ */