/* 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.] */#include <stdio.h>#include "cryptlib.h"#include <openssl/bn.h>#include <openssl/dh.h>#ifndef OPENSSL_NO_ENGINE#include <openssl/engine.h>#endifconst char *DH_version="Diffie-Hellman" OPENSSL_VERSION_PTEXT;static const DH_METHOD *default_DH_method = NULL;void DH_set_default_method(const DH_METHOD *meth)	{	default_DH_method = meth;	}const DH_METHOD *DH_get_default_method(void)	{	if(!default_DH_method)		default_DH_method = DH_OpenSSL();	return default_DH_method;	}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;	}DH *DH_new(void)	{	return DH_new_method(NULL);	}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);	}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);	}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);	}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);        }int DH_set_ex_data(DH *d, int idx, void *arg)	{	return(CRYPTO_set_ex_data(&d->ex_data,idx,arg));	}void *DH_get_ex_data(DH *d, int idx)	{	return(CRYPTO_get_ex_data(&d->ex_data,idx));	}int DH_size(const DH *dh)	{	return(BN_num_bytes(dh->p));	}