2 * Copyright 1995-2021 The OpenSSL Project Authors. All Rights Reserved.
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
10 #include <openssl/opensslconf.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>
33 static EVP_PKEY *dsa_to_dh(EVP_PKEY *dh);
35 typedef enum OPTION_choice {
37 OPT_INFORM, OPT_OUTFORM, OPT_IN, OPT_OUT,
38 OPT_ENGINE, OPT_CHECK, OPT_TEXT, OPT_NOOUT,
39 OPT_DSAPARAM, OPT_2, OPT_3, OPT_5,
40 OPT_R_ENUM, OPT_PROV_ENUM
43 const OPTIONS dhparam_options[] = {
44 {OPT_HELP_STR, 1, '-', "Usage: %s [options] [numbits]\n"},
46 OPT_SECTION("General"),
47 {"help", OPT_HELP, '-', "Display this summary"},
48 {"check", OPT_CHECK, '-', "Check the DH parameters"},
49 #if !defined(OPENSSL_NO_DSA) || !defined(OPENSSL_NO_DEPRECATED_3_0)
50 {"dsaparam", OPT_DSAPARAM, '-',
51 "Read or generate DSA parameters, convert to DH"},
53 #ifndef OPENSSL_NO_ENGINE
54 {"engine", OPT_ENGINE, 's', "Use engine e, possibly a hardware device"},
58 {"in", OPT_IN, '<', "Input file"},
59 {"inform", OPT_INFORM, 'F', "Input format, DER or PEM"},
61 OPT_SECTION("Output"),
62 {"out", OPT_OUT, '>', "Output file"},
63 {"outform", OPT_OUTFORM, 'F', "Output format, DER or PEM"},
64 {"text", OPT_TEXT, '-', "Print a text form of the DH parameters"},
65 {"noout", OPT_NOOUT, '-', "Don't output any DH parameters"},
66 {"2", OPT_2, '-', "Generate parameters using 2 as the generator value"},
67 {"3", OPT_3, '-', "Generate parameters using 3 as the generator value"},
68 {"5", OPT_5, '-', "Generate parameters using 5 as the generator value"},
74 {"numbits", 0, 0, "Number of bits if generating parameters (optional)"},
78 int dhparam_main(int argc, char **argv)
80 BIO *in = NULL, *out = NULL;
81 EVP_PKEY *pkey = NULL, *tmppkey = NULL;
82 EVP_PKEY_CTX *ctx = NULL;
83 char *infile = NULL, *outfile = NULL, *prog;
86 int text = 0, ret = 1, num = 0, g = 0;
87 int informat = FORMAT_PEM, outformat = FORMAT_PEM, check = 0, noout = 0;
90 prog = opt_init(argc, argv, dhparam_options);
91 while ((o = opt_next()) != OPT_EOF) {
96 BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
99 opt_help(dhparam_options);
103 if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &informat))
107 if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &outformat))
117 e = setup_engine(opt_arg(), 0);
145 if (!opt_provider(o))
151 /* One optional argument, bitsize to generate. */
152 argc = opt_num_rest();
155 if (!opt_int(argv[0], &num) || num <= 0)
157 } else if (!opt_check_rest_arg(NULL)) {
160 if (!app_RAND_load())
168 "Error, generator may not be chosen for DSA parameters\n");
172 out = bio_open_default(outfile, 'w', outformat);
181 const char *alg = dsaparam ? "DSA" : "DH";
183 ctx = EVP_PKEY_CTX_new_from_name(NULL, alg, NULL);
186 "Error, %s param generation context allocation failed\n",
190 EVP_PKEY_CTX_set_cb(ctx, progress_cb);
191 EVP_PKEY_CTX_set_app_data(ctx, bio_err);
193 "Generating %s parameters, %d bit long %sprime\n",
194 alg, num, dsaparam ? "" : "safe ");
196 if (EVP_PKEY_paramgen_init(ctx) <= 0) {
198 "Error, unable to initialise %s parameters\n",
204 if (!EVP_PKEY_CTX_set_dsa_paramgen_bits(ctx, num)) {
205 BIO_printf(bio_err, "Error, unable to set DSA prime length\n");
209 if (!EVP_PKEY_CTX_set_dh_paramgen_prime_len(ctx, num)) {
210 BIO_printf(bio_err, "Error, unable to set DH prime length\n");
213 if (!EVP_PKEY_CTX_set_dh_paramgen_generator(ctx, g)) {
214 BIO_printf(bio_err, "Error, unable to set generator\n");
219 tmppkey = app_paramgen(ctx, alg);
220 EVP_PKEY_CTX_free(ctx);
223 pkey = dsa_to_dh(tmppkey);
226 EVP_PKEY_free(tmppkey);
232 OSSL_DECODER_CTX *decoderctx = NULL;
233 const char *keytype = "DH";
236 in = bio_open_default(infile, 'r', informat);
242 * We assume we're done unless we explicitly want to retry and set
247 * We set NULL for the keytype to allow any key type. We don't know
248 * if we're going to get DH or DHX (or DSA in the event of dsaparam).
249 * We check that we got one of those key types afterwards.
252 = OSSL_DECODER_CTX_new_for_pkey(&tmppkey,
253 (informat == FORMAT_ASN1)
256 (informat == FORMAT_ASN1)
258 OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS,
261 if (decoderctx != NULL
262 && !OSSL_DECODER_from_bio(decoderctx, in)
263 && informat == FORMAT_ASN1
264 && strcmp(keytype, "DH") == 0) {
266 * When reading DER we explicitly state the expected keytype
267 * because, unlike PEM, there is no header to declare what
268 * the contents of the DER file are. The decoders just try
269 * and guess. Unfortunately with DHX key types they may guess
270 * wrong and think we have a DSA keytype. Therefore we try
271 * both DH and DHX sequentially.
275 * BIO_reset() returns 0 for success for file BIOs only!!!
276 * This won't work for stdin (and never has done)
278 if (BIO_reset(in) == 0)
281 OSSL_DECODER_CTX_free(decoderctx);
283 if (tmppkey == NULL) {
284 BIO_printf(bio_err, "Error, unable to load parameters\n");
289 if (!EVP_PKEY_is_a(tmppkey, "DSA")) {
290 BIO_printf(bio_err, "Error, unable to load DSA parameters\n");
293 pkey = dsa_to_dh(tmppkey);
297 if (!EVP_PKEY_is_a(tmppkey, "DH")
298 && !EVP_PKEY_is_a(tmppkey, "DHX")) {
299 BIO_printf(bio_err, "Error, unable to load DH parameters\n");
308 EVP_PKEY_print_params(out, pkey, 4, NULL);
311 ctx = EVP_PKEY_CTX_new_from_pkey(NULL, pkey, NULL);
313 BIO_printf(bio_err, "Error, failed to check DH parameters\n");
316 if (!EVP_PKEY_param_check(ctx)) {
317 BIO_printf(bio_err, "Error, invalid parameters generated\n");
320 BIO_printf(bio_err, "DH parameters appear to be ok.\n");
324 OSSL_ENCODER_CTX *ectx =
325 OSSL_ENCODER_CTX_new_for_pkey(pkey,
326 OSSL_KEYMGMT_SELECT_DOMAIN_PARAMETERS,
327 outformat == FORMAT_ASN1
331 if (ectx == NULL || !OSSL_ENCODER_to_bio(ectx, out)) {
332 OSSL_ENCODER_CTX_free(ectx);
333 BIO_printf(bio_err, "Error, unable to write DH parameters\n");
336 OSSL_ENCODER_CTX_free(ectx);
341 ERR_print_errors(bio_err);
345 EVP_PKEY_free(tmppkey);
346 EVP_PKEY_CTX_free(ctx);
352 * Historically we had the low level call DSA_dup_DH() to do this.
353 * That is now deprecated with no replacement. Since we still need to do this
354 * for backwards compatibility reasons, we do it "manually".
356 static EVP_PKEY *dsa_to_dh(EVP_PKEY *dh)
358 OSSL_PARAM_BLD *tmpl = NULL;
359 OSSL_PARAM *params = NULL;
360 BIGNUM *bn_p = NULL, *bn_q = NULL, *bn_g = NULL;
361 EVP_PKEY_CTX *ctx = NULL;
362 EVP_PKEY *pkey = NULL;
364 if (!EVP_PKEY_get_bn_param(dh, OSSL_PKEY_PARAM_FFC_P, &bn_p)
365 || !EVP_PKEY_get_bn_param(dh, OSSL_PKEY_PARAM_FFC_Q, &bn_q)
366 || !EVP_PKEY_get_bn_param(dh, OSSL_PKEY_PARAM_FFC_G, &bn_g)) {
367 BIO_printf(bio_err, "Error, failed to set DH parameters\n");
371 if ((tmpl = OSSL_PARAM_BLD_new()) == NULL
372 || !OSSL_PARAM_BLD_push_BN(tmpl, OSSL_PKEY_PARAM_FFC_P,
374 || !OSSL_PARAM_BLD_push_BN(tmpl, OSSL_PKEY_PARAM_FFC_Q,
376 || !OSSL_PARAM_BLD_push_BN(tmpl, OSSL_PKEY_PARAM_FFC_G,
378 || (params = OSSL_PARAM_BLD_to_param(tmpl)) == NULL) {
379 BIO_printf(bio_err, "Error, failed to set DH parameters\n");
383 ctx = EVP_PKEY_CTX_new_from_name(NULL, "DHX", NULL);
385 || EVP_PKEY_fromdata_init(ctx) <= 0
386 || EVP_PKEY_fromdata(ctx, &pkey, EVP_PKEY_KEY_PARAMETERS, params) <= 0) {
387 BIO_printf(bio_err, "Error, failed to set DH parameters\n");
392 EVP_PKEY_CTX_free(ctx);
393 OSSL_PARAM_free(params);
394 OSSL_PARAM_BLD_free(tmpl);