/*

 * Copyright 2001-2018 The OpenSSL Project Authors. All Rights Reserved.

 *

 * Licensed under the OpenSSL license (the "License").  You may not use

 * this file except in compliance with the License.  You can obtain a copy

 * in the file LICENSE in the source distribution or at

 * https://www.openssl.org/source/license.html

 */

#include "eng_int.h"

static ENGINE_TABLE *dh_table = NULL;

static const int dummy_nid = 1;

void ENGINE_unregister_DH(ENGINE *e)

{

    engine_table_unregister(&dh_table, e);

}

static void engine_unregister_all_DH(void)

{

    engine_table_cleanup(&dh_table);

}

int ENGINE_register_DH(ENGINE *e)

{

    if (e->dh_meth)

        return engine_table_register(&dh_table,

                                     engine_unregister_all_DH, e, &dummy_nid,

                                     1, 0);

    return 1;

}

void ENGINE_register_all_DH(void)

{

    ENGINE *e;

    for (e = ENGINE_get_first(); e; e = ENGINE_get_next(e))

        ENGINE_register_DH(e);

}

int ENGINE_set_default_DH(ENGINE *e)

{

    if (e->dh_meth)

        return engine_table_register(&dh_table,

                                     engine_unregister_all_DH, e, &dummy_nid,

                                     1, 1);

    return 1;

}

/*

 * Exposed API function to get a functional reference from the implementation

 * table (ie. try to get a functional reference from the tabled structural

 * references).

 */

ENGINE *ENGINE_get_default_DH(void)

{

    return engine_table_select(&dh_table, dummy_nid);

}

/* Obtains an DH implementation from an ENGINE functional reference */

const DH_METHOD *ENGINE_get_DH(const ENGINE *e)

{

    return e->dh_meth;

}

/* Sets an DH implementation in an ENGINE structure */

int ENGINE_set_DH(ENGINE *e, const DH_METHOD *dh_meth)

{

    e->dh_meth = dh_meth;

    return 1;

}