/* apps/dh.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>	/* for OPENSSL_NO_DH */

#ifndef OPENSSL_NO_DH

#include <stdio.h>

#include <stdlib.h>

#include <time.h>

#include <string.h>

#include "apps.h"

#include <openssl/bio.h>

#include <openssl/err.h>

#include <openssl/bn.h>

#include <openssl/dh.h>

#include <openssl/x509.h>

#include <openssl/pem.h>

#undef PROG

#define PROG	dh_main

/* -inform arg	- input format - default PEM (DER or PEM)

 * -outform arg - output format - default PEM

 * -in arg	- input file - default stdin

 * -out arg	- output file - default stdout

 * -check	- check the parameters are ok

 * -noout

 * -text

 * -C

 */

int MAIN(int, char **);

int MAIN(int argc, char **argv)

	{

#ifndef OPENSSL_NO_ENGINE

	ENGINE *e = NULL;

#endif

	DH *dh=NULL;

	int i,badops=0,text=0;

	BIO *in=NULL,*out=NULL;

	int informat,outformat,check=0,noout=0,C=0,ret=1;

	char *infile,*outfile,*prog;

#ifndef OPENSSL_NO_ENGINE

	char *engine;

#endif

	apps_startup();

	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;

#ifndef OPENSSL_NO_ENGINE

	engine=NULL;

#endif

	infile=NULL;

	outfile=NULL;

	informat=FORMAT_PEM;

	outformat=FORMAT_PEM;

	prog=argv[0];

	argc--;

	argv++;

	while (argc >= 1)

		{

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

			{

			if (--argc < 1) goto bad;

			informat=str2fmt(*(++argv));

			}

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

			{

			if (--argc < 1) goto bad;

			outformat=str2fmt(*(++argv));

			}

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

			{

			if (--argc < 1) goto bad;

			infile= *(++argv);

			}

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

			{

			if (--argc < 1) goto bad;

			outfile= *(++argv);

			}

#ifndef OPENSSL_NO_ENGINE

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

			{

			if (--argc < 1) goto bad;

			engine= *(++argv);

			}

#endif

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

			check=1;

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

			text=1;

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

			C=1;

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

			noout=1;

		else

			{

			BIO_printf(bio_err,"unknown option %s\n",*argv);

			badops=1;

			break;

			}

		argc--;

		argv++;

		}

	if (badops)

		{

bad:

		BIO_printf(bio_err,"%s [options] <infile >outfile\n",prog);

		BIO_printf(bio_err,"where options are\n");

		BIO_printf(bio_err," -inform arg   input format - one of DER PEM\n");

		BIO_printf(bio_err," -outform arg  output format - one of DER PEM\n");

		BIO_printf(bio_err," -in arg       input file\n");

		BIO_printf(bio_err," -out arg      output file\n");

		BIO_printf(bio_err," -check        check the DH parameters\n");

		BIO_printf(bio_err," -text         print a text form of the DH parameters\n");

		BIO_printf(bio_err," -C            Output C code\n");

		BIO_printf(bio_err," -noout        no output\n");

#ifndef OPENSSL_NO_ENGINE

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

#endif

		goto end;

		}

	ERR_load_crypto_strings();

#ifndef OPENSSL_NO_ENGINE

        e = setup_engine(bio_err, engine, 0);

#endif

	in=BIO_new(BIO_s_file());

	out=BIO_new(BIO_s_file());

	if ((in == NULL) || (out == NULL))

		{

		ERR_print_errors(bio_err);

		goto end;

		}

	if (infile == NULL)

		BIO_set_fp(in,stdin,BIO_NOCLOSE);

	else

		{

		if (BIO_read_filename(in,infile) <= 0)

			{

			perror(infile);

			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	(informat == FORMAT_ASN1)

		dh=d2i_DHparams_bio(in,NULL);

	else if (informat == FORMAT_PEM)

		dh=PEM_read_bio_DHparams(in,NULL,NULL,NULL);

	else

		{

		BIO_printf(bio_err,"bad input format specified\n");

		goto end;

		}

	if (dh == NULL)

		{

		BIO_printf(bio_err,"unable to load DH parameters\n");

		ERR_print_errors(bio_err);

		goto end;

		}

	if (text)

		{

		DHparams_print(out,dh);

#ifdef undef

		printf("p=");

		BN_print(stdout,dh->p);

		printf("\ng=");

		BN_print(stdout,dh->g);

		printf("\n");

		if (dh->length != 0)

			printf("recommended private length=%ld\n",dh->length);

#endif

		}

	if (check)

		{

		if (!DH_check(dh,&i))

			{

			ERR_print_errors(bio_err);

			goto end;

			}

		if (i & DH_CHECK_P_NOT_PRIME)

			printf("p value is not prime\n");

		if (i & DH_CHECK_P_NOT_SAFE_PRIME)

			printf("p value is not a safe prime\n");

		if (i & DH_UNABLE_TO_CHECK_GENERATOR)

			printf("unable to check the generator value\n");

		if (i & DH_NOT_SUITABLE_GENERATOR)

			printf("the g value is not a generator\n");

		if (i == 0)

			printf("DH parameters appear to be ok.\n");

		}

	if (C)

		{

		unsigned char *data;

		int len,l,bits;

		len=BN_num_bytes(dh->p);

		bits=BN_num_bits(dh->p);

		data=(unsigned char *)OPENSSL_malloc(len);

		if (data == NULL)

			{

			perror("OPENSSL_malloc");

			goto end;

			}

		l=BN_bn2bin(dh->p,data);

		printf("static unsigned char dh%d_p[]={",bits);

		for (i=0; i<l; i++)

			{

			if ((i%12) == 0) printf("\n\t");

			printf("0x%02X,",data[i]);

			}

		printf("\n\t};\n");

		l=BN_bn2bin(dh->g,data);

		printf("static unsigned char dh%d_g[]={",bits);

		for (i=0; i<l; i++)

			{

			if ((i%12) == 0) printf("\n\t");

			printf("0x%02X,",data[i]);

			}

		printf("\n\t};\n\n");

		printf("DH *get_dh%d()\n\t{\n",bits);

		printf("\tDH *dh;\n\n");

		printf("\tif ((dh=DH_new()) == NULL) return(NULL);\n");

		printf("\tdh->p=BN_bin2bn(dh%d_p,sizeof(dh%d_p),NULL);\n",

			bits,bits);

		printf("\tdh->g=BN_bin2bn(dh%d_g,sizeof(dh%d_g),NULL);\n",

			bits,bits);

		printf("\tif ((dh->p == NULL) || (dh->g == NULL))\n");

		printf("\t\treturn(NULL);\n");

		printf("\treturn(dh);\n\t}\n");

		OPENSSL_free(data);

		}

	if (!noout)

		{

		if 	(outformat == FORMAT_ASN1)

			i=i2d_DHparams_bio(out,dh);

		else if (outformat == FORMAT_PEM)

			i=PEM_write_bio_DHparams(out,dh);

		else	{

			BIO_printf(bio_err,"bad output format specified for outfile\n");

			goto end;

			}

		if (!i)

			{

			BIO_printf(bio_err,"unable to write DH parameters\n");

			ERR_print_errors(bio_err);

			goto end;

			}

		}

	ret=0;

end:

	if (in != NULL) BIO_free(in);

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

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

	apps_shutdown();

	OPENSSL_EXIT(ret);

	}

#endif