/* crypto/dh/dh_lib.c */

/* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)

 * All rights reserved.

 *

 * This package is an SSL implementation written

 * by Eric Young (eay@cryptsoft.com).

 * The implementation was written so as to conform with Netscapes SSL.

 * 

 * This library is free for commercial and non-commercial use as long as

 * the following conditions are aheared to.  The following conditions

 * apply to all code found in this distribution, be it the RC4, RSA,

 * lhash, DES, etc., code; not just the SSL code.  The SSL documentation

 * included with this distribution is covered by the same copyright terms

 * except that the holder is Tim Hudson (tjh@cryptsoft.com).

 * 

 * Copyright remains Eric Young's, and as such any Copyright notices in

 * the code are not to be removed.

 * If this package is used in a product, Eric Young should be given attribution

 * as the author of the parts of the library used.

 * This can be in the form of a textual message at program startup or

 * in documentation (online or textual) provided with the package.

 * 

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in the

 *    documentation and/or other materials provided with the distribution.

 * 3. All advertising materials mentioning features or use of this software

 *    must display the following acknowledgement:

 *    "This product includes cryptographic software written by

 *     Eric Young (eay@cryptsoft.com)"

 *    The word 'cryptographic' can be left out if the rouines from the library

 *    being used are not cryptographic related :-).

 * 4. If you include any Windows specific code (or a derivative thereof) from 

 *    the apps directory (application code) you must include an acknowledgement:

 *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"

 * 

 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 * 

 * The licence and distribution terms for any publically available version or

 * derivative of this code cannot be changed.  i.e. this code cannot simply be

 * copied and put under another distribution licence

 * [including the GNU Public Licence.]

 */

/*

 © Portions copyright (c) 2006 Nokia Corporation.  All rights reserved.

 */

#include <stdio.h>

#include "cryptlib.h"

#include <openssl/bn.h>

#include <openssl/dh.h>

#ifndef OPENSSL_NO_ENGINE

#include <openssl/engine.h>

#endif

#if (defined(SYMBIAN) && (defined(__WINSCW__) || defined(__WINS__)))

#include "libcrypto_wsd_macros.h"

#include "libcrypto_wsd.h"

#endif

const char DH_version[]="Diffie-Hellman" OPENSSL_VERSION_PTEXT;

#ifndef EMULATOR

static const DH_METHOD *default_DH_method = NULL;

#else

GET_STATIC_VAR_FROM_TLS(default_DH_method,dh_lib,const DH_METHOD *)

#define default_DH_method (*GET_WSD_VAR_NAME(default_DH_method,dh_lib, s)())

#endif

EXPORT_C void DH_set_default_method(const DH_METHOD *meth)

	{

	default_DH_method = meth;

	}

EXPORT_C const DH_METHOD *DH_get_default_method(void)

	{

	if(!default_DH_method)

		default_DH_method = DH_OpenSSL();

	return default_DH_method;

	}

EXPORT_C int DH_set_method(DH *dh, const DH_METHOD *meth)

	{

	/* NB: The caller is specifically setting a method, so it's not up to us

	 * to deal with which ENGINE it comes from. */

        const DH_METHOD *mtmp;

        mtmp = dh->meth;

        if (mtmp->finish) mtmp->finish(dh);

#ifndef OPENSSL_NO_ENGINE

	if (dh->engine)

		{

		ENGINE_finish(dh->engine);

		dh->engine = NULL;

		}

#endif

        dh->meth = meth;

        if (meth->init) meth->init(dh);

        return 1;

	}

EXPORT_C DH *DH_new(void)

	{

	return DH_new_method(NULL);

	}

EXPORT_C DH *DH_new_method(ENGINE *engine)

	{

	DH *ret;

	ret=(DH *)OPENSSL_malloc(sizeof(DH));

	if (ret == NULL)

		{

		DHerr(DH_F_DH_NEW_METHOD,ERR_R_MALLOC_FAILURE);

		return(NULL);

		}

	ret->meth = DH_get_default_method();

#ifndef OPENSSL_NO_ENGINE

	if (engine)

		{

		if (!ENGINE_init(engine))

			{

			DHerr(DH_F_DH_NEW_METHOD, ERR_R_ENGINE_LIB);

			OPENSSL_free(ret);

			return NULL;

			}

		ret->engine = engine;

		}

	else

		ret->engine = ENGINE_get_default_DH();

	if(ret->engine)

		{

		ret->meth = ENGINE_get_DH(ret->engine);

		if(!ret->meth)

			{

			DHerr(DH_F_DH_NEW_METHOD,ERR_R_ENGINE_LIB);

			ENGINE_finish(ret->engine);

			OPENSSL_free(ret);

			return NULL;

			}

		}

#endif

	ret->pad=0;

	ret->version=0;

	ret->p=NULL;

	ret->g=NULL;

	ret->length=0;

	ret->pub_key=NULL;

	ret->priv_key=NULL;

	ret->q=NULL;

	ret->j=NULL;

	ret->seed = NULL;

	ret->seedlen = 0;

	ret->counter = NULL;

	ret->method_mont_p=NULL;

	ret->references = 1;

	ret->flags=ret->meth->flags;

	CRYPTO_new_ex_data(CRYPTO_EX_INDEX_DH, ret, &ret->ex_data);

	if ((ret->meth->init != NULL) && !ret->meth->init(ret))

		{

#ifndef OPENSSL_NO_ENGINE

		if (ret->engine)

			ENGINE_finish(ret->engine);

#endif

		CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, ret, &ret->ex_data);

		OPENSSL_free(ret);

		ret=NULL;

		}

	return(ret);

	}

EXPORT_C void DH_free(DH *r)

	{

	int i;

	if(r == NULL) return;

	i = CRYPTO_add(&r->references, -1, CRYPTO_LOCK_DH);

#ifdef REF_PRINT

	REF_PRINT("DH",r);

#endif

	if (i > 0) return;

#ifdef REF_CHECK

	if (i < 0)

		{

		fprintf(stderr,"DH_free, bad reference count\n");

		abort();

	}

#endif

	if (r->meth->finish)

		r->meth->finish(r);

#ifndef OPENSSL_NO_ENGINE

	if (r->engine)

		ENGINE_finish(r->engine);

#endif

	CRYPTO_free_ex_data(CRYPTO_EX_INDEX_DH, r, &r->ex_data);

	if (r->p != NULL) BN_clear_free(r->p);

	if (r->g != NULL) BN_clear_free(r->g);

	if (r->q != NULL) BN_clear_free(r->q);

	if (r->j != NULL) BN_clear_free(r->j);

	if (r->seed) OPENSSL_free(r->seed);

	if (r->counter != NULL) BN_clear_free(r->counter);

	if (r->pub_key != NULL) BN_clear_free(r->pub_key);

	if (r->priv_key != NULL) BN_clear_free(r->priv_key);

	OPENSSL_free(r);

	}

EXPORT_C int DH_up_ref(DH *r)

	{

	int i = CRYPTO_add(&r->references, 1, CRYPTO_LOCK_DH);

#ifdef REF_PRINT

	REF_PRINT("DH",r);

#endif

#ifdef REF_CHECK

	if (i < 2)

		{

		fprintf(stderr, "DH_up, bad reference count\n");

		abort();

		}

#endif

	return ((i > 1) ? 1 : 0);

	}

EXPORT_C int DH_get_ex_new_index(long argl, void *argp, CRYPTO_EX_new *new_func,

	     CRYPTO_EX_dup *dup_func, CRYPTO_EX_free *free_func)

        {

	return CRYPTO_get_ex_new_index(CRYPTO_EX_INDEX_DH, argl, argp,

				new_func, dup_func, free_func);

        }

EXPORT_C int DH_set_ex_data(DH *d, int idx, void *arg)

	{

	return(CRYPTO_set_ex_data(&d->ex_data,idx,arg));

	}

EXPORT_C void *DH_get_ex_data(DH *d, int idx)

	{

	return(CRYPTO_get_ex_data(&d->ex_data,idx));

	}

EXPORT_C int DH_size(const DH *dh)

	{

	return(BN_num_bytes(dh->p));

	}