1 /* $OpenBSD: prime.c,v 1.18 2023/07/23 11:39:29 tb Exp $ */
2 /* ====================================================================
3 * Copyright (c) 2004 The OpenSSL Project. All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 *
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in
14 * the documentation and/or other materials provided with the
15 * distribution.
16 *
17 * 3. All advertising materials mentioning features or use of this
18 * software must display the following acknowledgment:
19 * "This product includes software developed by the OpenSSL Project
20 * for use in the OpenSSL Toolkit. (http://www.openssl.org/)"
21 *
22 * 4. The names "OpenSSL Toolkit" and "OpenSSL Project" must not be used to
23 * endorse or promote products derived from this software without
24 * prior written permission. For written permission, please contact
25 * openssl-core@openssl.org.
26 *
27 * 5. Products derived from this software may not be called "OpenSSL"
28 * nor may "OpenSSL" appear in their names without prior written
29 * permission of the OpenSSL Project.
30 *
31 * 6. Redistributions of any form whatsoever must retain the following
32 * acknowledgment:
33 * "This product includes software developed by the OpenSSL Project
34 * for use in the OpenSSL Toolkit (http://www.openssl.org/)"
35 *
36 * THIS SOFTWARE IS PROVIDED BY THE OpenSSL PROJECT ``AS IS'' AND ANY
37 * EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
38 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
39 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE OpenSSL PROJECT OR
40 * ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
41 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
42 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
43 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
44 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
45 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
46 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
47 * OF THE POSSIBILITY OF SUCH DAMAGE.
48 *
49 */
50
51 #include <string.h>
52 #include <limits.h>
53
54 #include "apps.h"
55
56 #include <openssl/bn.h>
57 #include <openssl/err.h>
58
59 static struct {
60 int bits;
61 int checks;
62 int generate;
63 int hex;
64 int safe;
65 } cfg;
66
67 static const struct option prime_options[] = {
68 {
69 .name = "bits",
70 .argname = "n",
71 .desc = "Number of bits in the generated prime number",
72 .type = OPTION_ARG_INT,
73 .opt.value = &cfg.bits,
74 },
75 {
76 .name = "checks",
77 .argname = "n",
78 .desc = "Miller-Rabin probabilistic primality test iterations",
79 .type = OPTION_ARG_INT,
80 .opt.value = &cfg.checks,
81 },
82 {
83 .name = "generate",
84 .desc = "Generate a pseudo-random prime number",
85 .type = OPTION_FLAG,
86 .opt.flag = &cfg.generate,
87 },
88 {
89 .name = "hex",
90 .desc = "Hexadecimal prime numbers",
91 .type = OPTION_FLAG,
92 .opt.flag = &cfg.hex,
93 },
94 {
95 .name = "safe",
96 .desc = "Generate only \"safe\" prime numbers",
97 .type = OPTION_FLAG,
98 .opt.flag = &cfg.safe,
99 },
100 {NULL},
101 };
102
103 static void
prime_usage(void)104 prime_usage(void)
105 {
106 fprintf(stderr,
107 "usage: prime [-bits n] [-checks n] [-generate] [-hex] [-safe] "
108 "p\n");
109 options_usage(prime_options);
110 }
111
112 int
prime_main(int argc,char ** argv)113 prime_main(int argc, char **argv)
114 {
115 BIGNUM *bn = NULL;
116 char *prime = NULL;
117 BIO *bio_out;
118 char *s;
119 int is_prime, ret = 1;
120
121 if (pledge("stdio rpath", NULL) == -1) {
122 perror("pledge");
123 exit(1);
124 }
125
126 memset(&cfg, 0, sizeof(cfg));
127
128 /* Default iterations for Miller-Rabin probabilistic primality test. */
129 cfg.checks = 20;
130
131 if (options_parse(argc, argv, prime_options, &prime, NULL) != 0) {
132 prime_usage();
133 return (1);
134 }
135
136 if (prime == NULL && cfg.generate == 0) {
137 BIO_printf(bio_err, "No prime specified.\n");
138 prime_usage();
139 return (1);
140 }
141
142 if ((bio_out = BIO_new(BIO_s_file())) == NULL) {
143 ERR_print_errors(bio_err);
144 return (1);
145 }
146 BIO_set_fp(bio_out, stdout, BIO_NOCLOSE);
147
148 if (cfg.generate != 0) {
149 if (cfg.bits == 0) {
150 BIO_printf(bio_err, "Specify the number of bits.\n");
151 goto end;
152 }
153 bn = BN_new();
154 if (!bn) {
155 BIO_printf(bio_err, "Out of memory.\n");
156 goto end;
157 }
158 if (!BN_generate_prime_ex(bn, cfg.bits,
159 cfg.safe, NULL, NULL, NULL)) {
160 BIO_printf(bio_err, "Prime generation error.\n");
161 goto end;
162 }
163 s = cfg.hex ? BN_bn2hex(bn) : BN_bn2dec(bn);
164 if (s == NULL) {
165 BIO_printf(bio_err, "Out of memory.\n");
166 goto end;
167 }
168 BIO_printf(bio_out, "%s\n", s);
169 free(s);
170 } else {
171 if (cfg.hex) {
172 if (!BN_hex2bn(&bn, prime)) {
173 BIO_printf(bio_err, "%s is an invalid hex "
174 "value.\n", prime);
175 goto end;
176 }
177 } else {
178 if (!BN_dec2bn(&bn, prime)) {
179 BIO_printf(bio_err, "%s is an invalid decimal "
180 "value.\n", prime);
181 goto end;
182 }
183 }
184
185 is_prime = BN_is_prime_ex(bn, cfg.checks, NULL, NULL);
186 if (is_prime < 0) {
187 BIO_printf(bio_err, "BN_is_prime_ex failed.\n");
188 goto end;
189 }
190 BIO_printf(bio_out, "%s is %sprime\n", prime,
191 is_prime == 1 ? "" : "not ");
192 }
193
194 ret = 0;
195
196 end:
197 BN_free(bn);
198 BIO_free_all(bio_out);
199
200 return (ret);
201 }
202