/* apps/gendh.c */

/* obsoleted by dhparam.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 <openssl/opensslconf.h>

/* Until the key-gen callbacks are modified to use newer prototypes, we allow

 * deprecated functions for openssl-internal code */

#ifdef OPENSSL_NO_DEPRECATED

#undef OPENSSL_NO_DEPRECATED

#endif

#ifndef OPENSSL_NO_DH

#include <stdio.h>

#include <string.h>

#include <sys/types.h>

#include <sys/stat.h>

#include "apps.h"

#include <openssl/bio.h>

#include <openssl/rand.h>

#include <openssl/err.h>

#include <openssl/bn.h>

#include <openssl/dh.h>

#include <openssl/x509.h>

#include <openssl/pem.h>

#define DEFBITS	512

#undef PROG

#define PROG gendh_main

static int MS_CALLBACK dh_cb(int p, int n, BN_GENCB *cb);

int MAIN(int, char **);

int MAIN(int argc, char **argv)

	{

	BN_GENCB cb;

#ifndef OPENSSL_NO_ENGINE

	ENGINE *e = NULL;

#endif

	DH *dh=NULL;

	int ret=1,num=DEFBITS;

	int g=2;

	char *outfile=NULL;

	char *inrand=NULL;

#ifndef OPENSSL_NO_ENGINE

	char *engine=NULL;

#endif

	BIO *out=NULL;

	apps_startup();

	BN_GENCB_set(&cb, dh_cb, bio_err);

	if (bio_err == NULL)

		if ((bio_err=BIO_new(BIO_s_file())) != NULL)

			BIO_set_fp(bio_err,stderr,BIO_NOCLOSE|BIO_FP_TEXT);

	if (!load_config(bio_err, NULL))

		goto end;

	argv++;

	argc--;

	for (;;)

		{

		if (argc <= 0) break;

		if (strcmp(*argv,"-out") == 0)

			{

			if (--argc < 1) goto bad;

			outfile= *(++argv);

			}

		else if (strcmp(*argv,"-2") == 0)

			g=2;

	/*	else if (strcmp(*argv,"-3") == 0)

			g=3; */

		else if (strcmp(*argv,"-5") == 0)

			g=5;

#ifndef OPENSSL_NO_ENGINE

		else if (strcmp(*argv,"-engine") == 0)

			{

			if (--argc < 1) goto bad;

			engine= *(++argv);

			}

#endif

		else if (strcmp(*argv,"-rand") == 0)

			{

			if (--argc < 1) goto bad;

			inrand= *(++argv);

			}

		else

			break;

		argv++;

		argc--;

		}

	if ((argc >= 1) && ((sscanf(*argv,"%d",&num) == 0) || (num < 0)))

		{

bad:

		BIO_printf(bio_err,"usage: gendh [args] [numbits]\n");

		BIO_printf(bio_err," -out file - output the key to 'file\n");

		BIO_printf(bio_err," -2        - use 2 as the generator value\n");

	/*	BIO_printf(bio_err," -3        - use 3 as the generator value\n"); */

		BIO_printf(bio_err," -5        - use 5 as the generator value\n");

#ifndef OPENSSL_NO_ENGINE

		BIO_printf(bio_err," -engine e - use engine e, possibly a hardware device.\n");

#endif

		BIO_printf(bio_err," -rand file%cfile%c...\n", LIST_SEPARATOR_CHAR, LIST_SEPARATOR_CHAR);

		BIO_printf(bio_err,"           - load the file (or the files in the directory) into\n");

		BIO_printf(bio_err,"             the random number generator\n");

		goto end;

		}

#ifndef OPENSSL_NO_ENGINE

        e = setup_engine(bio_err, engine, 0);

#endif

	out=BIO_new(BIO_s_file());

	if (out == NULL)

		{

		ERR_print_errors(bio_err);

		goto end;

		}

	if (outfile == NULL)

		{

		BIO_set_fp(out,stdout,BIO_NOCLOSE);

#ifdef OPENSSL_SYS_VMS

		{

		BIO *tmpbio = BIO_new(BIO_f_linebuffer());

		out = BIO_push(tmpbio, out);

		}

#endif

		}

	else

		{

		if (BIO_write_filename(out,outfile) <= 0)

			{

			perror(outfile);

			goto end;

			}

		}

	if (!app_RAND_load_file(NULL, bio_err, 1) && inrand == NULL)

		{

		BIO_printf(bio_err,"warning, not much extra random data, consider using the -rand option\n");

		}

	if (inrand != NULL)

		BIO_printf(bio_err,"%ld semi-random bytes loaded\n",

			app_RAND_load_files(inrand));

	BIO_printf(bio_err,"Generating DH parameters, %d bit long safe prime, generator %d\n",num,g);

	BIO_printf(bio_err,"This is going to take a long time\n");

	if(((dh = DH_new()) == NULL) || !DH_generate_parameters_ex(dh, num, g, &cb))

		goto end;

	app_RAND_write_file(NULL, bio_err);

	if (!PEM_write_bio_DHparams(out,dh))

		goto end;

	ret=0;

end:

	if (ret != 0)

		ERR_print_errors(bio_err);

	if (out != NULL) BIO_free_all(out);

	if (dh != NULL) DH_free(dh);

	apps_shutdown();

	OPENSSL_EXIT(ret);

	}

static int MS_CALLBACK dh_cb(int p, int n, BN_GENCB *cb)

	{

	char c='*';

	if (p == 0) c='.';

	if (p == 1) c='+';

	if (p == 2) c='*';

	if (p == 3) c='\n';

	BIO_write(cb->arg,&c,1);

	(void)BIO_flush(cb->arg);

#ifdef LINT

	p=n;

#endif

	return 1;

	}

#endif