1 /*
2 * Copyright 1995-2023 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10 #include <openssl/opensslconf.h>
11
12 #include <stdio.h>
13 #include <stdlib.h>
14 #include <time.h>
15 #include <string.h>
16 #include "apps.h"
17 #include "progs.h"
18 #include <openssl/bio.h>
19 #include <openssl/err.h>
20 #include <openssl/bn.h>
21 #include <openssl/dsa.h>
22 #include <openssl/dh.h>
23 #include <openssl/x509.h>
24 #include <openssl/pem.h>
25 #include <openssl/core_names.h>
26 #include <openssl/core_dispatch.h>
27 #include <openssl/param_build.h>
28 #include <openssl/encoder.h>
29 #include <openssl/decoder.h>
30
31 #define DEFBITS 2048
32
33 static EVP_PKEY *dsa_to_dh(EVP_PKEY *dh);
34
35 static int verbose = 1;
36
37 typedef enum OPTION_choice {
38 OPT_COMMON,
39 OPT_INFORM, OPT_OUTFORM, OPT_IN, OPT_OUT,
40 OPT_ENGINE, OPT_CHECK, OPT_TEXT, OPT_NOOUT,
41 OPT_DSAPARAM, OPT_2, OPT_3, OPT_5, OPT_VERBOSE, OPT_QUIET,
42 OPT_R_ENUM, OPT_PROV_ENUM
43 } OPTION_CHOICE;
44
45 const OPTIONS dhparam_options[] = {
46 {OPT_HELP_STR, 1, '-', "Usage: %s [options] [numbits]\n"},
47
48 OPT_SECTION("General"),
49 {"help", OPT_HELP, '-', "Display this summary"},
50 {"check", OPT_CHECK, '-', "Check the DH parameters"},
51 #if !defined(OPENSSL_NO_DSA) || !defined(OPENSSL_NO_DEPRECATED_3_0)
52 {"dsaparam", OPT_DSAPARAM, '-',
53 "Read or generate DSA parameters, convert to DH"},
54 #endif
55 #ifndef OPENSSL_NO_ENGINE
56 {"engine", OPT_ENGINE, 's', "Use engine e, possibly a hardware device"},
57 #endif
58
59 OPT_SECTION("Input"),
60 {"in", OPT_IN, '<', "Input file"},
61 {"inform", OPT_INFORM, 'F', "Input format, DER or PEM"},
62
63 OPT_SECTION("Output"),
64 {"out", OPT_OUT, '>', "Output file"},
65 {"outform", OPT_OUTFORM, 'F', "Output format, DER or PEM"},
66 {"text", OPT_TEXT, '-', "Print a text form of the DH parameters"},
67 {"noout", OPT_NOOUT, '-', "Don't output any DH parameters"},
68 {"2", OPT_2, '-', "Generate parameters using 2 as the generator value"},
69 {"3", OPT_3, '-', "Generate parameters using 3 as the generator value"},
70 {"5", OPT_5, '-', "Generate parameters using 5 as the generator value"},
71 {"verbose", OPT_VERBOSE, '-', "Verbose output"},
72 {"quiet", OPT_QUIET, '-', "Terse output"},
73
74 OPT_R_OPTIONS,
75 OPT_PROV_OPTIONS,
76
77 OPT_PARAMETERS(),
78 {"numbits", 0, 0, "Number of bits if generating parameters (optional)"},
79 {NULL}
80 };
81
dhparam_main(int argc,char ** argv)82 int dhparam_main(int argc, char **argv)
83 {
84 BIO *in = NULL, *out = NULL;
85 EVP_PKEY *pkey = NULL, *tmppkey = NULL;
86 EVP_PKEY_CTX *ctx = NULL;
87 char *infile = NULL, *outfile = NULL, *prog;
88 ENGINE *e = NULL;
89 int dsaparam = 0;
90 int text = 0, ret = 1, num = 0, g = 0;
91 int informat = FORMAT_PEM, outformat = FORMAT_PEM, check = 0, noout = 0;
92 OPTION_CHOICE o;
93
94 prog = opt_init(argc, argv, dhparam_options);
95 while ((o = opt_next()) != OPT_EOF) {
96 switch (o) {
97 case OPT_EOF:
98 case OPT_ERR:
99 opthelp:
100 BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
101 goto end;
102 case OPT_HELP:
103 opt_help(dhparam_options);
104 ret = 0;
105 goto end;
106 case OPT_INFORM:
107 if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &informat))
108 goto opthelp;
109 break;
110 case OPT_OUTFORM:
111 if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &outformat))
112 goto opthelp;
113 break;
114 case OPT_IN:
115 infile = opt_arg();
116 break;
117 case OPT_OUT:
118 outfile = opt_arg();
119 break;
120 case OPT_ENGINE:
121 e = setup_engine(opt_arg(), 0);
122 break;
123 case OPT_CHECK:
124 check = 1;
125 break;
126 case OPT_TEXT:
127 text = 1;
128 break;
129 case OPT_DSAPARAM:
130 dsaparam = 1;
131 break;
132 case OPT_2:
133 g = 2;
134 break;
135 case OPT_3:
136 g = 3;
137 break;
138 case OPT_5:
139 g = 5;
140 break;
141 case OPT_NOOUT:
142 noout = 1;
143 break;
144 case OPT_VERBOSE:
145 verbose = 1;
146 break;
147 case OPT_QUIET:
148 verbose = 0;
149 break;
150 case OPT_R_CASES:
151 if (!opt_rand(o))
152 goto end;
153 break;
154 case OPT_PROV_CASES:
155 if (!opt_provider(o))
156 goto end;
157 break;
158 }
159 }
160
161 /* One optional argument, bitsize to generate. */
162 argc = opt_num_rest();
163 argv = opt_rest();
164 if (argc == 1) {
165 if (!opt_int(argv[0], &num) || num <= 0)
166 goto opthelp;
167 } else if (!opt_check_rest_arg(NULL)) {
168 goto opthelp;
169 }
170 if (!app_RAND_load())
171 goto end;
172
173 if (g && !num)
174 num = DEFBITS;
175
176 if (dsaparam && g) {
177 BIO_printf(bio_err,
178 "Error, generator may not be chosen for DSA parameters\n");
179 goto end;
180 }
181
182 /* DH parameters */
183 if (num && !g)
184 g = 2;
185
186 if (num) {
187 const char *alg = dsaparam ? "DSA" : "DH";
188
189 if (infile != NULL) {
190 BIO_printf(bio_err, "Warning, input file %s ignored\n", infile);
191 }
192
193 ctx = EVP_PKEY_CTX_new_from_name(app_get0_libctx(), alg, app_get0_propq());
194 if (ctx == NULL) {
195 BIO_printf(bio_err,
196 "Error, %s param generation context allocation failed\n",
197 alg);
198 goto end;
199 }
200 EVP_PKEY_CTX_set_app_data(ctx, bio_err);
201 if (verbose) {
202 EVP_PKEY_CTX_set_cb(ctx, progress_cb);
203 BIO_printf(bio_err,
204 "Generating %s parameters, %d bit long %sprime\n",
205 alg, num, dsaparam ? "" : "safe ");
206 }
207
208 if (EVP_PKEY_paramgen_init(ctx) <= 0) {
209 BIO_printf(bio_err,
210 "Error, unable to initialise %s parameters\n",
211 alg);
212 goto end;
213 }
214
215 if (dsaparam) {
216 if (EVP_PKEY_CTX_set_dsa_paramgen_bits(ctx, num) <= 0) {
217 BIO_printf(bio_err, "Error, unable to set DSA prime length\n");
218 goto end;
219 }
220 } else {
221 if (EVP_PKEY_CTX_set_dh_paramgen_prime_len(ctx, num) <= 0) {
222 BIO_printf(bio_err, "Error, unable to set DH prime length\n");
223 goto end;
224 }
225 if (EVP_PKEY_CTX_set_dh_paramgen_generator(ctx, g) <= 0) {
226 BIO_printf(bio_err, "Error, unable to set generator\n");
227 goto end;
228 }
229 }
230
231 tmppkey = app_paramgen(ctx, alg);
232 if (tmppkey == NULL)
233 goto end;
234 EVP_PKEY_CTX_free(ctx);
235 ctx = NULL;
236 if (dsaparam) {
237 pkey = dsa_to_dh(tmppkey);
238 if (pkey == NULL)
239 goto end;
240 EVP_PKEY_free(tmppkey);
241 } else {
242 pkey = tmppkey;
243 }
244 tmppkey = NULL;
245 } else {
246 OSSL_DECODER_CTX *decoderctx = NULL;
247 const char *keytype = "DH";
248 int done;
249
250 in = bio_open_default(infile, 'r', informat);
251 if (in == NULL)
252 goto end;
253
254 do {
255 /*
256 * We assume we're done unless we explicitly want to retry and set
257 * this to 0 below.
258 */
259 done = 1;
260 /*
261 * We set NULL for the keytype to allow any key type. We don't know
262 * if we're going to get DH or DHX (or DSA in the event of dsaparam).
263 * We check that we got one of those key types afterwards.
264 */
265 decoderctx
266 = OSSL_DECODER_CTX_new_for_pkey(&tmppkey,
267 (informat == FORMAT_ASN1)
268 ? "DER" : "PEM",
269 NULL,
270 (informat == FORMAT_ASN1)
271 ? keytype : NULL,
272 OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS,
273 NULL, NULL);
274
275 if (decoderctx != NULL
276 && !OSSL_DECODER_from_bio(decoderctx, in)
277 && informat == FORMAT_ASN1
278 && strcmp(keytype, "DH") == 0) {
279 /*
280 * When reading DER we explicitly state the expected keytype
281 * because, unlike PEM, there is no header to declare what
282 * the contents of the DER file are. The decoders just try
283 * and guess. Unfortunately with DHX key types they may guess
284 * wrong and think we have a DSA keytype. Therefore, we try
285 * both DH and DHX sequentially.
286 */
287 keytype = "DHX";
288 /*
289 * BIO_reset() returns 0 for success for file BIOs only!!!
290 * This won't work for stdin (and never has done)
291 */
292 if (BIO_reset(in) == 0)
293 done = 0;
294 }
295 OSSL_DECODER_CTX_free(decoderctx);
296 } while (!done);
297 if (tmppkey == NULL) {
298 BIO_printf(bio_err, "Error, unable to load parameters\n");
299 goto end;
300 }
301
302 if (dsaparam) {
303 if (!EVP_PKEY_is_a(tmppkey, "DSA")) {
304 BIO_printf(bio_err, "Error, unable to load DSA parameters\n");
305 goto end;
306 }
307 pkey = dsa_to_dh(tmppkey);
308 if (pkey == NULL)
309 goto end;
310 } else {
311 if (!EVP_PKEY_is_a(tmppkey, "DH")
312 && !EVP_PKEY_is_a(tmppkey, "DHX")) {
313 BIO_printf(bio_err, "Error, unable to load DH parameters\n");
314 goto end;
315 }
316 pkey = tmppkey;
317 tmppkey = NULL;
318 }
319 }
320
321 out = bio_open_default(outfile, 'w', outformat);
322 if (out == NULL)
323 goto end;
324
325 if (text)
326 EVP_PKEY_print_params(out, pkey, 4, NULL);
327
328 if (check) {
329 ctx = EVP_PKEY_CTX_new_from_pkey(app_get0_libctx(), pkey, app_get0_propq());
330 if (ctx == NULL) {
331 BIO_printf(bio_err, "Error, failed to check DH parameters\n");
332 goto end;
333 }
334 if (EVP_PKEY_param_check(ctx) <= 0) {
335 BIO_printf(bio_err, "Error, invalid parameters generated\n");
336 goto end;
337 }
338 BIO_printf(bio_err, "DH parameters appear to be ok.\n");
339 }
340
341 if (!noout) {
342 OSSL_ENCODER_CTX *ectx =
343 OSSL_ENCODER_CTX_new_for_pkey(pkey,
344 OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS,
345 outformat == FORMAT_ASN1
346 ? "DER" : "PEM",
347 NULL, NULL);
348
349 if (ectx == NULL || !OSSL_ENCODER_to_bio(ectx, out)) {
350 OSSL_ENCODER_CTX_free(ectx);
351 BIO_printf(bio_err, "Error, unable to write DH parameters\n");
352 goto end;
353 }
354 OSSL_ENCODER_CTX_free(ectx);
355 }
356 ret = 0;
357 end:
358 if (ret != 0)
359 ERR_print_errors(bio_err);
360 BIO_free(in);
361 BIO_free_all(out);
362 EVP_PKEY_free(pkey);
363 EVP_PKEY_free(tmppkey);
364 EVP_PKEY_CTX_free(ctx);
365 release_engine(e);
366 return ret;
367 }
368
369 /*
370 * Historically we had the low-level call DSA_dup_DH() to do this.
371 * That is now deprecated with no replacement. Since we still need to do this
372 * for backwards compatibility reasons, we do it "manually".
373 */
dsa_to_dh(EVP_PKEY * dh)374 static EVP_PKEY *dsa_to_dh(EVP_PKEY *dh)
375 {
376 OSSL_PARAM_BLD *tmpl = NULL;
377 OSSL_PARAM *params = NULL;
378 BIGNUM *bn_p = NULL, *bn_q = NULL, *bn_g = NULL;
379 EVP_PKEY_CTX *ctx = NULL;
380 EVP_PKEY *pkey = NULL;
381
382 if (!EVP_PKEY_get_bn_param(dh, OSSL_PKEY_PARAM_FFC_P, &bn_p)
383 || !EVP_PKEY_get_bn_param(dh, OSSL_PKEY_PARAM_FFC_Q, &bn_q)
384 || !EVP_PKEY_get_bn_param(dh, OSSL_PKEY_PARAM_FFC_G, &bn_g)) {
385 BIO_printf(bio_err, "Error, failed to set DH parameters\n");
386 goto err;
387 }
388
389 if ((tmpl = OSSL_PARAM_BLD_new()) == NULL
390 || !OSSL_PARAM_BLD_push_BN(tmpl, OSSL_PKEY_PARAM_FFC_P,
391 bn_p)
392 || !OSSL_PARAM_BLD_push_BN(tmpl, OSSL_PKEY_PARAM_FFC_Q,
393 bn_q)
394 || !OSSL_PARAM_BLD_push_BN(tmpl, OSSL_PKEY_PARAM_FFC_G,
395 bn_g)
396 || (params = OSSL_PARAM_BLD_to_param(tmpl)) == NULL) {
397 BIO_printf(bio_err, "Error, failed to set DH parameters\n");
398 goto err;
399 }
400
401 ctx = EVP_PKEY_CTX_new_from_name(app_get0_libctx(), "DHX", app_get0_propq());
402 if (ctx == NULL
403 || EVP_PKEY_fromdata_init(ctx) <= 0
404 || EVP_PKEY_fromdata(ctx, &pkey, EVP_PKEY_KEY_PARAMETERS, params) <= 0) {
405 BIO_printf(bio_err, "Error, failed to set DH parameters\n");
406 goto err;
407 }
408
409 err:
410 EVP_PKEY_CTX_free(ctx);
411 OSSL_PARAM_free(params);
412 OSSL_PARAM_BLD_free(tmpl);
413 BN_free(bn_p);
414 BN_free(bn_q);
415 BN_free(bn_g);
416 return pkey;
417 }
418
419
