1 /* $OpenBSD: gendh.c,v 1.14 2023/03/06 14:32:06 tb 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 #include <openssl/opensslconf.h>
60
61 /* Until the key-gen callbacks are modified to use newer prototypes, we allow
62 * deprecated functions for openssl-internal code */
63 #ifdef OPENSSL_NO_DEPRECATED
64 #undef OPENSSL_NO_DEPRECATED
65 #endif
66
67 #ifndef OPENSSL_NO_DH
68
69 #include <sys/types.h>
70 #include <sys/stat.h>
71
72 #include <limits.h>
73 #include <stdio.h>
74 #include <string.h>
75
76 #include "apps.h"
77
78 #include <openssl/bio.h>
79 #include <openssl/bn.h>
80 #include <openssl/dh.h>
81 #include <openssl/err.h>
82 #include <openssl/pem.h>
83 #include <openssl/x509.h>
84
85 #define DEFBITS 512
86
87 static int dh_cb(int p, int n, BN_GENCB *cb);
88
89 static struct {
90 int g;
91 char *outfile;
92 } cfg;
93
94 static const struct option gendh_options[] = {
95 {
96 .name = "2",
97 .desc = "Generate DH parameters with a generator value of 2 "
98 "(default)",
99 .type = OPTION_VALUE,
100 .value = 2,
101 .opt.value = &cfg.g,
102 },
103 {
104 .name = "5",
105 .desc = "Generate DH parameters with a generator value of 5",
106 .type = OPTION_VALUE,
107 .value = 5,
108 .opt.value = &cfg.g,
109 },
110 {
111 .name = "out",
112 .argname = "file",
113 .desc = "Output file (default stdout)",
114 .type = OPTION_ARG,
115 .opt.arg = &cfg.outfile,
116 },
117 { NULL },
118 };
119
120 static void
gendh_usage(void)121 gendh_usage(void)
122 {
123 fprintf(stderr,
124 "usage: gendh [-2 | -5] [-out file] [numbits]\n\n");
125 options_usage(gendh_options);
126 }
127
128 int
gendh_main(int argc,char ** argv)129 gendh_main(int argc, char **argv)
130 {
131 BN_GENCB *cb = NULL;
132 DH *dh = NULL;
133 int ret = 1, numbits = DEFBITS;
134 BIO *out = NULL;
135 char *strbits = NULL;
136
137 if (pledge("stdio cpath wpath rpath", NULL) == -1) {
138 perror("pledge");
139 exit(1);
140 }
141
142 if ((cb = BN_GENCB_new()) == NULL) {
143 BIO_printf(bio_err, "Error allocating BN_GENCB object\n");
144 goto end;
145 }
146
147 BN_GENCB_set(cb, dh_cb, bio_err);
148
149 memset(&cfg, 0, sizeof(cfg));
150
151 cfg.g = 2;
152
153 if (options_parse(argc, argv, gendh_options, &strbits, NULL) != 0) {
154 gendh_usage();
155 goto end;
156 }
157
158 if (strbits != NULL) {
159 const char *errstr;
160 numbits = strtonum(strbits, 0, INT_MAX, &errstr);
161 if (errstr) {
162 fprintf(stderr, "Invalid number of bits: %s\n", errstr);
163 goto end;
164 }
165 }
166
167 out = BIO_new(BIO_s_file());
168 if (out == NULL) {
169 ERR_print_errors(bio_err);
170 goto end;
171 }
172 if (cfg.outfile == NULL) {
173 BIO_set_fp(out, stdout, BIO_NOCLOSE);
174 } else {
175 if (BIO_write_filename(out, cfg.outfile) <= 0) {
176 perror(cfg.outfile);
177 goto end;
178 }
179 }
180
181 BIO_printf(bio_err, "Generating DH parameters, %d bit long safe prime,"
182 " generator %d\n", numbits, cfg.g);
183 BIO_printf(bio_err, "This is going to take a long time\n");
184
185 if (((dh = DH_new()) == NULL) ||
186 !DH_generate_parameters_ex(dh, numbits, cfg.g, cb))
187 goto end;
188
189 if (!PEM_write_bio_DHparams(out, dh))
190 goto end;
191 ret = 0;
192 end:
193 if (ret != 0)
194 ERR_print_errors(bio_err);
195 BIO_free_all(out);
196 BN_GENCB_free(cb);
197 DH_free(dh);
198
199 return (ret);
200 }
201
202 static int
dh_cb(int p,int n,BN_GENCB * cb)203 dh_cb(int p, int n, BN_GENCB *cb)
204 {
205 char c = '*';
206
207 if (p == 0)
208 c = '.';
209 if (p == 1)
210 c = '+';
211 if (p == 2)
212 c = '*';
213 if (p == 3)
214 c = '\n';
215 BIO_write(BN_GENCB_get_arg(cb), &c, 1);
216 (void) BIO_flush(BN_GENCB_get_arg(cb));
217 return 1;
218 }
219 #endif
220