1 /* $OpenBSD: dhparam.c,v 1.7 2015/10/10 22:28:51 doug Exp $ */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3  * All rights reserved.
4  *
5  * This package is an SSL implementation written
6  * by Eric Young (eay@cryptsoft.com).
7  * The implementation was written so as to conform with Netscapes SSL.
8  *
9  * This library is free for commercial and non-commercial use as long as
10  * the following conditions are aheared to.  The following conditions
11  * apply to all code found in this distribution, be it the RC4, RSA,
12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13  * included with this distribution is covered by the same copyright terms
14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15  *
16  * Copyright remains Eric Young's, and as such any Copyright notices in
17  * the code are not to be removed.
18  * If this package is used in a product, Eric Young should be given attribution
19  * as the author of the parts of the library used.
20  * This can be in the form of a textual message at program startup or
21  * in documentation (online or textual) provided with the package.
22  *
23  * Redistribution and use in source and binary forms, with or without
24  * modification, are permitted provided that the following conditions
25  * are met:
26  * 1. Redistributions of source code must retain the copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 3. All advertising materials mentioning features or use of this software
32  *    must display the following acknowledgement:
33  *    "This product includes cryptographic software written by
34  *     Eric Young (eay@cryptsoft.com)"
35  *    The word 'cryptographic' can be left out if the rouines from the library
36  *    being used are not cryptographic related :-).
37  * 4. If you include any Windows specific code (or a derivative thereof) from
38  *    the apps directory (application code) you must include an acknowledgement:
39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40  *
41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51  * SUCH DAMAGE.
52  *
53  * The licence and distribution terms for any publically available version or
54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
55  * copied and put under another distribution licence
56  * [including the GNU Public Licence.]
57  */
58 /* ====================================================================
59  * Copyright (c) 1998-2000 The OpenSSL Project.  All rights reserved.
60  *
61  * Redistribution and use in source and binary forms, with or without
62  * modification, are permitted provided that the following conditions
63  * are met:
64  *
65  * 1. Redistributions of source code must retain the above copyright
66  *    notice, this list of conditions and the following disclaimer.
67  *
68  * 2. Redistributions in binary form must reproduce the above copyright
69  *    notice, this list of conditions and the following disclaimer in
70  *    the documentation and/or other materials provided with the
71  *    distribution.
72  *
73  * 3. All advertising materials mentioning features or use of this
74  *    software must display the following acknowledgment:
75  *    "This product includes software developed by the OpenSSL Project
76  *    for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
77  *
78  * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
79  *    endorse or promote products derived from this software without
80  *    prior written permission. For written permission, please contact
81  *    openssl-core@openssl.org.
82  *
83  * 5. Products derived from this software may not be called "OpenSSL"
84  *    nor may "OpenSSL" appear in their names without prior written
85  *    permission of the OpenSSL Project.
86  *
87  * 6. Redistributions of any form whatsoever must retain the following
88  *    acknowledgment:
89  *    "This product includes software developed by the OpenSSL Project
90  *    for use in the OpenSSL Toolkit (http://www.openssl.org/)"
91  *
92  * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
93  * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
94  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
95  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE OpenSSL PROJECT OR
96  * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
97  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
98  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
99  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
100  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
101  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
102  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
103  * OF THE POSSIBILITY OF SUCH DAMAGE.
104  * ====================================================================
105  *
106  * This product includes cryptographic software written by Eric Young
107  * (eay@cryptsoft.com).  This product includes software written by Tim
108  * Hudson (tjh@cryptsoft.com).
109  *
110  */
111 
112 #include <openssl/opensslconf.h>	/* for OPENSSL_NO_DH */
113 
114 #ifndef OPENSSL_NO_DH
115 
116 #include <stdio.h>
117 #include <stdlib.h>
118 #include <string.h>
119 #include <time.h>
120 
121 #include "apps.h"
122 
123 #include <openssl/bio.h>
124 #include <openssl/bn.h>
125 #include <openssl/err.h>
126 #include <openssl/dh.h>
127 #include <openssl/pem.h>
128 #include <openssl/x509.h>
129 
130 #include <openssl/dsa.h>
131 
132 #define DEFBITS	2048
133 
134 struct {
135 	int C;
136 	int check;
137 	int dsaparam;
138 	int g;
139 	char *infile;
140 	int informat;
141 	int noout;
142 	char *outfile;
143 	int outformat;
144 	int text;
145 } dhparam_config;
146 
147 struct option dhparam_options[] = {
148 	{
149 		.name = "2",
150 		.desc = "Generate DH parameters with a generator value of 2 "
151 		    "(default)",
152 		.type = OPTION_VALUE,
153 		.opt.value = &dhparam_config.g,
154 		.value = 2,
155 	},
156 	{
157 		.name = "5",
158 		.desc = "Generate DH parameters with a generator value of 5",
159 		.type = OPTION_VALUE,
160 		.opt.value = &dhparam_config.g,
161 		.value = 5,
162 	},
163 	{
164 		.name = "C",
165 		.desc = "Convert DH parameters into C code",
166 		.type = OPTION_FLAG,
167 		.opt.flag = &dhparam_config.C,
168 	},
169 	{
170 		.name = "check",
171 		.desc = "Check the DH parameters",
172 		.type = OPTION_FLAG,
173 		.opt.flag = &dhparam_config.check,
174 	},
175 	{
176 		.name = "dsaparam",
177 		.desc = "Read or generate DSA parameters and convert to DH",
178 		.type = OPTION_FLAG,
179 		.opt.flag = &dhparam_config.dsaparam,
180 	},
181 	{
182 		.name = "in",
183 		.argname = "file",
184 		.desc = "Input file (default stdin)",
185 		.type = OPTION_ARG,
186 		.opt.arg = &dhparam_config.infile,
187 	},
188 	{
189 		.name = "inform",
190 		.argname = "format",
191 		.desc = "Input format (DER or PEM (default))",
192 		.type = OPTION_ARG_FORMAT,
193 		.opt.value = &dhparam_config.informat,
194 	},
195 	{
196 		.name = "noout",
197 		.desc = "Do not output encoded version of DH parameters",
198 		.type = OPTION_FLAG,
199 		.opt.flag = &dhparam_config.noout,
200 	},
201 	{
202 		.name = "out",
203 		.argname = "file",
204 		.desc = "Output file (default stdout)",
205 		.type = OPTION_ARG,
206 		.opt.arg = &dhparam_config.outfile,
207 	},
208 	{
209 		.name = "outform",
210 		.argname = "format",
211 		.desc = "Output format (DER or PEM (default))",
212 		.type = OPTION_ARG_FORMAT,
213 		.opt.value = &dhparam_config.outformat,
214 	},
215 	{
216 		.name = "text",
217 		.desc = "Print DH parameters in plain text",
218 		.type = OPTION_FLAG,
219 		.opt.flag = &dhparam_config.text,
220 	},
221 	{ NULL },
222 };
223 
224 static void
225 dhparam_usage()
226 {
227 	fprintf(stderr,
228 	    "usage: dhparam [-2 | -5] [-C] [-check] [-dsaparam]\n"
229 	    "    [-in file] [-inform DER | PEM] [-noout] [-out file]\n"
230 	    "    [-outform DER | PEM] [-text] [numbits]\n\n");
231 	options_usage(dhparam_options);
232 }
233 
234 static int dh_cb(int p, int n, BN_GENCB * cb);
235 
236 int
237 dhparam_main(int argc, char **argv)
238 {
239 	BIO *in = NULL, *out = NULL;
240 	char *num_bits = NULL;
241 	DH *dh = NULL;
242 	int num = 0;
243 	int ret = 1;
244 	int i;
245 
246 	if (single_execution) {
247 		if (pledge("stdio rpath wpath cpath", NULL) == -1) {
248 			perror("pledge");
249 			exit(1);
250 		}
251 	}
252 
253 	memset(&dhparam_config, 0, sizeof(dhparam_config));
254 
255 	dhparam_config.informat = FORMAT_PEM;
256 	dhparam_config.outformat = FORMAT_PEM;
257 
258 	if (options_parse(argc, argv, dhparam_options, &num_bits, NULL) != 0) {
259 		dhparam_usage();
260 		return (1);
261 	}
262 
263 	if (num_bits != NULL) {
264 		if(sscanf(num_bits, "%d", &num) == 0 || num <= 0) {
265 			BIO_printf(bio_err, "invalid number of bits: %s\n",
266 			    num_bits);
267 			return (1);
268 		}
269 	}
270 
271 	if (dhparam_config.g && !num)
272 		num = DEFBITS;
273 
274 	if (dhparam_config.dsaparam) {
275 		if (dhparam_config.g) {
276 			BIO_printf(bio_err, "generator may not be chosen for DSA parameters\n");
277 			goto end;
278 		}
279 	} else {
280 		/* DH parameters */
281 		if (num && !dhparam_config.g)
282 			dhparam_config.g = 2;
283 	}
284 
285 	if (num) {
286 
287 		BN_GENCB cb;
288 		BN_GENCB_set(&cb, dh_cb, bio_err);
289 		if (dhparam_config.dsaparam) {
290 			DSA *dsa = DSA_new();
291 
292 			BIO_printf(bio_err, "Generating DSA parameters, %d bit long prime\n", num);
293 			if (!dsa || !DSA_generate_parameters_ex(dsa, num,
294 				NULL, 0, NULL, NULL, &cb)) {
295 				if (dsa)
296 					DSA_free(dsa);
297 				ERR_print_errors(bio_err);
298 				goto end;
299 			}
300 			dh = DSA_dup_DH(dsa);
301 			DSA_free(dsa);
302 			if (dh == NULL) {
303 				ERR_print_errors(bio_err);
304 				goto end;
305 			}
306 		} else {
307 			dh = DH_new();
308 			BIO_printf(bio_err, "Generating DH parameters, %d bit long safe prime, generator %d\n", num, dhparam_config.g);
309 			BIO_printf(bio_err, "This is going to take a long time\n");
310 			if (!dh || !DH_generate_parameters_ex(dh, num, dhparam_config.g, &cb)) {
311 				ERR_print_errors(bio_err);
312 				goto end;
313 			}
314 		}
315 	} else {
316 
317 		in = BIO_new(BIO_s_file());
318 		if (in == NULL) {
319 			ERR_print_errors(bio_err);
320 			goto end;
321 		}
322 		if (dhparam_config.infile == NULL)
323 			BIO_set_fp(in, stdin, BIO_NOCLOSE);
324 		else {
325 			if (BIO_read_filename(in, dhparam_config.infile) <= 0) {
326 				perror(dhparam_config.infile);
327 				goto end;
328 			}
329 		}
330 
331 		if (dhparam_config.informat != FORMAT_ASN1 &&
332 		    dhparam_config.informat != FORMAT_PEM) {
333 			BIO_printf(bio_err, "bad input format specified\n");
334 			goto end;
335 		}
336 		if (dhparam_config.dsaparam) {
337 			DSA *dsa;
338 
339 			if (dhparam_config.informat == FORMAT_ASN1)
340 				dsa = d2i_DSAparams_bio(in, NULL);
341 			else	/* informat == FORMAT_PEM */
342 				dsa = PEM_read_bio_DSAparams(in, NULL, NULL, NULL);
343 
344 			if (dsa == NULL) {
345 				BIO_printf(bio_err, "unable to load DSA parameters\n");
346 				ERR_print_errors(bio_err);
347 				goto end;
348 			}
349 			dh = DSA_dup_DH(dsa);
350 			DSA_free(dsa);
351 			if (dh == NULL) {
352 				ERR_print_errors(bio_err);
353 				goto end;
354 			}
355 		} else
356 		{
357 			if (dhparam_config.informat == FORMAT_ASN1)
358 				dh = d2i_DHparams_bio(in, NULL);
359 			else	/* informat == FORMAT_PEM */
360 				dh = PEM_read_bio_DHparams(in, NULL, NULL, NULL);
361 
362 			if (dh == NULL) {
363 				BIO_printf(bio_err, "unable to load DH parameters\n");
364 				ERR_print_errors(bio_err);
365 				goto end;
366 			}
367 		}
368 
369 		/* dh != NULL */
370 	}
371 
372 	out = BIO_new(BIO_s_file());
373 	if (out == NULL) {
374 		ERR_print_errors(bio_err);
375 		goto end;
376 	}
377 	if (dhparam_config.outfile == NULL) {
378 		BIO_set_fp(out, stdout, BIO_NOCLOSE);
379 	} else {
380 		if (BIO_write_filename(out, dhparam_config.outfile) <= 0) {
381 			perror(dhparam_config.outfile);
382 			goto end;
383 		}
384 	}
385 
386 
387 	if (dhparam_config.text) {
388 		DHparams_print(out, dh);
389 	}
390 	if (dhparam_config.check) {
391 		if (!DH_check(dh, &i)) {
392 			ERR_print_errors(bio_err);
393 			goto end;
394 		}
395 		if (i & DH_CHECK_P_NOT_PRIME)
396 			printf("p value is not prime\n");
397 		if (i & DH_CHECK_P_NOT_SAFE_PRIME)
398 			printf("p value is not a safe prime\n");
399 		if (i & DH_UNABLE_TO_CHECK_GENERATOR)
400 			printf("unable to check the generator value\n");
401 		if (i & DH_NOT_SUITABLE_GENERATOR)
402 			printf("the g value is not a generator\n");
403 		if (i == 0)
404 			printf("DH parameters appear to be ok.\n");
405 	}
406 	if (dhparam_config.C) {
407 		unsigned char *data;
408 		int len, l, bits;
409 
410 		len = BN_num_bytes(dh->p);
411 		bits = BN_num_bits(dh->p);
412 		data = malloc(len);
413 		if (data == NULL) {
414 			perror("malloc");
415 			goto end;
416 		}
417 		printf("#ifndef HEADER_DH_H\n"
418 		    "#include <openssl/dh.h>\n"
419 		    "#endif\n");
420 		printf("DH *get_dh%d()\n\t{\n", bits);
421 
422 		l = BN_bn2bin(dh->p, data);
423 		printf("\tstatic unsigned char dh%d_p[] = {", bits);
424 		for (i = 0; i < l; i++) {
425 			if ((i % 12) == 0)
426 				printf("\n\t\t");
427 			printf("0x%02X, ", data[i]);
428 		}
429 		printf("\n\t\t};\n");
430 
431 		l = BN_bn2bin(dh->g, data);
432 		printf("\tstatic unsigned char dh%d_g[] = {", bits);
433 		for (i = 0; i < l; i++) {
434 			if ((i % 12) == 0)
435 				printf("\n\t\t");
436 			printf("0x%02X, ", data[i]);
437 		}
438 		printf("\n\t\t};\n");
439 
440 		printf("\tDH *dh;\n\n");
441 		printf("\tif ((dh = DH_new()) == NULL) return(NULL);\n");
442 		printf("\tdh->p = BN_bin2bn(dh%d_p, sizeof(dh%d_p), NULL);\n",
443 		    bits, bits);
444 		printf("\tdh->g = BN_bin2bn(dh%d_g, sizeof(dh%d_g), NULL);\n",
445 		    bits, bits);
446 		printf("\tif ((dh->p == NULL) || (dh->g == NULL))\n");
447 		printf("\t\t{ DH_free(dh); return(NULL); }\n");
448 		if (dh->length)
449 			printf("\tdh->length = %ld;\n", dh->length);
450 		printf("\treturn(dh);\n\t}\n");
451 		free(data);
452 	}
453 	if (!dhparam_config.noout) {
454 		if (dhparam_config.outformat == FORMAT_ASN1)
455 			i = i2d_DHparams_bio(out, dh);
456 		else if (dhparam_config.outformat == FORMAT_PEM)
457 			i = PEM_write_bio_DHparams(out, dh);
458 		else {
459 			BIO_printf(bio_err, "bad output format specified for outfile\n");
460 			goto end;
461 		}
462 		if (!i) {
463 			BIO_printf(bio_err, "unable to write DH parameters\n");
464 			ERR_print_errors(bio_err);
465 			goto end;
466 		}
467 	}
468 	ret = 0;
469 
470 end:
471 	BIO_free(in);
472 	if (out != NULL)
473 		BIO_free_all(out);
474 	if (dh != NULL)
475 		DH_free(dh);
476 
477 	return (ret);
478 }
479 
480 /* dh_cb is identical to dsa_cb in apps/dsaparam.c */
481 static int
482 dh_cb(int p, int n, BN_GENCB * cb)
483 {
484 	char c = '*';
485 
486 	if (p == 0)
487 		c = '.';
488 	if (p == 1)
489 		c = '+';
490 	if (p == 2)
491 		c = '*';
492 	if (p == 3)
493 		c = '\n';
494 	BIO_write(cb->arg, &c, 1);
495 	(void) BIO_flush(cb->arg);
496 	return 1;
497 }
498 
499 #endif
500