xref: /openbsd/usr.bin/openssl/prime.c (revision a7b8f3c1)
1 /* $OpenBSD: prime.c,v 1.6 2015/02/11 03:19:37 doug 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 struct {
60 	int bits;
61 	int checks;
62 	int generate;
63 	int hex;
64 	int safe;
65 } prime_config;
66 
67 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 = &prime_config.bits,
74 	},
75 	{
76 		.name = "checks",
77 		.argname = "n",
78 		.desc = "Miller-Rabin probablistic primality test iterations",
79 		.type = OPTION_ARG_INT,
80 		.opt.value = &prime_config.checks,
81 	},
82 	{
83 		.name = "generate",
84 		.desc = "Generate a pseudo-random prime number",
85 		.type = OPTION_FLAG,
86 		.opt.flag = &prime_config.generate,
87 	},
88 	{
89 		.name = "hex",
90 		.desc = "Hexadecimal prime numbers",
91 		.type = OPTION_FLAG,
92 		.opt.flag = &prime_config.hex,
93 	},
94 	{
95 		.name = "safe",
96 		.desc = "Generate only \"safe\" prime numbers",
97 		.type = OPTION_FLAG,
98 		.opt.flag = &prime_config.safe,
99 	},
100 	{NULL},
101 };
102 
103 static void
104 prime_usage()
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, char **);
113 
114 int
115 prime_main(int argc, char **argv)
116 {
117 	BIGNUM *bn = NULL;
118 	char *prime = NULL;
119 	BIO *bio_out;
120 	char *s;
121 	int ret = 1;
122 
123 	memset(&prime_config, 0, sizeof(prime_config));
124 
125 	/* Default iterations for Miller-Rabin probabilistic primality test. */
126 	prime_config.checks = 20;
127 
128 	if (options_parse(argc, argv, prime_options, &prime, NULL) != 0) {
129 		prime_usage();
130 		return (1);
131 	}
132 
133 	if (prime == NULL && prime_config.generate == 0) {
134 		BIO_printf(bio_err, "No prime specified.\n");
135 		prime_usage();
136 		return (1);
137 	}
138 
139 	if ((bio_out = BIO_new(BIO_s_file())) == NULL) {
140 		ERR_print_errors(bio_err);
141 		return (1);
142 	}
143 	BIO_set_fp(bio_out, stdout, BIO_NOCLOSE);
144 
145 	if (prime_config.generate != 0) {
146 		if (prime_config.bits == 0) {
147 			BIO_printf(bio_err, "Specify the number of bits.\n");
148 			goto end;
149 		}
150 		bn = BN_new();
151 		if (!bn) {
152 			BIO_printf(bio_err, "Out of memory.\n");
153 			goto end;
154 		}
155 		if (!BN_generate_prime_ex(bn, prime_config.bits,
156 		    prime_config.safe, NULL, NULL, NULL)) {
157 			BIO_printf(bio_err, "Prime generation error.\n");
158 			goto end;
159 		}
160 		s = prime_config.hex ? BN_bn2hex(bn) : BN_bn2dec(bn);
161 		if (s == NULL) {
162 			BIO_printf(bio_err, "Out of memory.\n");
163 			goto end;
164 		}
165 		BIO_printf(bio_out, "%s\n", s);
166 		free(s);
167 	} else {
168 		if (prime_config.hex) {
169 			if (!BN_hex2bn(&bn, prime)) {
170 				BIO_printf(bio_err, "%s is an invalid hex "
171 				    "value.\n", prime);
172 				goto end;
173 			}
174 		} else {
175 			if (!BN_dec2bn(&bn, prime)) {
176 				BIO_printf(bio_err, "%s is an invalid decimal "
177 				    "value.\n", prime);
178 				goto end;
179 			}
180 		}
181 
182 		BN_print(bio_out, bn);
183 		BIO_printf(bio_out, " is %sprime\n",
184 		    BN_is_prime_ex(bn, prime_config.checks,
185 			NULL, NULL) ? "" : "not ");
186 	}
187 
188 	ret = 0;
189 
190 end:
191 	BN_free(bn);
192 	BIO_free_all(bio_out);
193 
194 	return (ret);
195 }
196