1 /* $NetBSD: plainrsa-gen.c,v 1.7 2022/01/23 14:35:45 christos Exp $ */
2
3 /* Id: plainrsa-gen.c,v 1.6 2005/04/21 09:08:40 monas Exp */
4 /*
5 * Copyright (C) 2004 SuSE Linux AG, Nuernberg, Germany.
6 * Contributed by: Michal Ludvig <mludvig@suse.cz>, SUSE Labs
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 * 3. Neither the name of the project nor the names of its contributors
18 * may be used to endorse or promote products derived from this software
19 * without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 */
33
34 /* This file contains a generator for FreeS/WAN-style ipsec.secrets RSA keys. */
35
36 #include "config.h"
37
38 #include <stdio.h>
39 #include <string.h>
40 #include <errno.h>
41
42 #include <sys/types.h>
43 #include <sys/stat.h>
44 #include <sys/socket.h>
45 #include <unistd.h>
46 #include <fcntl.h>
47
48 #include <openssl/bio.h>
49 #include <openssl/bn.h>
50 #include <openssl/err.h>
51 #include <openssl/objects.h>
52 #include <openssl/pem.h>
53 #include <openssl/rsa.h>
54 #include <openssl/evp.h>
55 #ifdef HAVE_OPENSSL_ENGINE_H
56 #include <openssl/engine.h>
57 #endif
58
59 #include "misc.h"
60 #include "vmbuf.h"
61 #include "plog.h"
62 #include "crypto_openssl.h"
63
64 #include "package_version.h"
65
66 #define DEFAULT_PUBEXP RSA_F4
67
68 void
usage(char * argv0)69 usage (char *argv0)
70 {
71 fprintf(stderr, "Plain RSA key generator, part of %s\n", TOP_PACKAGE_STRING);
72 fprintf(stderr, "By Michal Ludvig (http://www.logix.cz/michal)\n");
73 fprintf(stderr, "\n");
74 fprintf(stderr, "Usage: %s [options]\n", argv0);
75 fprintf(stderr, "\n");
76 fprintf(stderr, " -b bits Generate <bits> long RSA key (default=1024)\n");
77 fprintf(stderr, " -e pubexp Public exponent to use (default=%#x)\n", DEFAULT_PUBEXP);
78 fprintf(stderr, " -f filename Filename to store the key to (default=stdout)\n");
79 fprintf(stderr, " -i filename Input source for format conversion\n");
80 fprintf(stderr, " -h Help\n");
81 fprintf(stderr, "\n");
82 fprintf(stderr, "Report bugs to <ipsec-tools-devel@lists.sourceforge.net>\n");
83 exit(1);
84 }
85
86 /*
87 * See RFC 2065, section 3.5 for details about the output format.
88 */
89 vchar_t *
mix_b64_pubkey(const RSA * key)90 mix_b64_pubkey(const RSA *key)
91 {
92 char *binbuf;
93 long binlen, ret;
94 vchar_t *res;
95
96 binlen = 1 + BN_num_bytes(RSA_get0_e(key)) + BN_num_bytes(RSA_get0_n(key));
97 binbuf = malloc(binlen);
98 memset(binbuf, 0, binlen);
99 binbuf[0] = BN_bn2bin(RSA_get0_e(key), (unsigned char *) &binbuf[1]);
100 ret = BN_bn2bin(RSA_get0_n(key), (unsigned char *) (&binbuf[binbuf[0] + 1]));
101 if (1 + binbuf[0] + ret != binlen) {
102 plog(LLV_ERROR, LOCATION, NULL,
103 "Pubkey generation failed. This is really strange...\n");
104 return NULL;
105 }
106
107 return base64_encode(binbuf, binlen);
108 }
109
110 char *
lowercase(char * input)111 lowercase(char *input)
112 {
113 char *ptr = input;
114 while (*ptr) {
115 if (*ptr >= 'A' && *ptr <= 'F')
116 *ptr -= 'A' - 'a';
117 *ptr++;
118 }
119
120 return input;
121 }
122
123 int
print_rsa_key(FILE * fp,const RSA * key)124 print_rsa_key(FILE *fp, const RSA *key)
125 {
126 vchar_t *pubkey64 = NULL;
127
128 pubkey64 = mix_b64_pubkey(key);
129 if (!pubkey64) {
130 fprintf(stderr, "mix_b64_pubkey(): %s\n", eay_strerror());
131 return -1;
132 }
133
134 fprintf(fp, "# : PUB 0s%s\n", pubkey64->v);
135 fprintf(fp, ": RSA\t{\n");
136 fprintf(fp, "\t# RSA %d bits\n", BN_num_bits(RSA_get0_n(key)));
137 fprintf(fp, "\t# pubkey=0s%s\n", pubkey64->v);
138 fprintf(fp, "\tModulus: 0x%s\n", lowercase(BN_bn2hex(RSA_get0_n(key))));
139 fprintf(fp, "\tPublicExponent: 0x%s\n", lowercase(BN_bn2hex(RSA_get0_e(key))));
140 fprintf(fp, "\tPrivateExponent: 0x%s\n", lowercase(BN_bn2hex(RSA_get0_d(key))));
141 fprintf(fp, "\tPrime1: 0x%s\n", lowercase(BN_bn2hex(RSA_get0_p(key))));
142 fprintf(fp, "\tPrime2: 0x%s\n", lowercase(BN_bn2hex(RSA_get0_q(key))));
143 fprintf(fp, "\tExponent1: 0x%s\n", lowercase(BN_bn2hex(RSA_get0_dmp1(key))));
144 fprintf(fp, "\tExponent2: 0x%s\n", lowercase(BN_bn2hex(RSA_get0_dmq1(key))));
145 fprintf(fp, "\tCoefficient: 0x%s\n", lowercase(BN_bn2hex(RSA_get0_iqmp(key))));
146 fprintf(fp, " }\n");
147
148 vfree(pubkey64);
149 return 0;
150 }
151
152 int
print_public_rsa_key(FILE * fp,const RSA * key)153 print_public_rsa_key(FILE *fp, const RSA *key)
154 {
155 vchar_t *pubkey64 = NULL;
156
157 pubkey64 = mix_b64_pubkey(key);
158 if (!pubkey64) {
159 fprintf(stderr, "mix_b64_pubkey(): %s\n", eay_strerror());
160 return -1;
161 }
162
163 fprintf(fp, ": PUB 0s%s\n", pubkey64->v);
164
165 vfree(pubkey64);
166 return 0;
167 }
168
169 int
convert_rsa_key(FILE * fpout,FILE * fpin)170 convert_rsa_key(FILE *fpout, FILE *fpin)
171 {
172 int ret;
173 RSA *key = NULL;
174
175 key = PEM_read_RSAPrivateKey(fpin, NULL, NULL, NULL);
176 if (key) {
177 ret = print_rsa_key(fpout, key);
178 RSA_free(key);
179
180 return ret;
181 }
182
183 rewind(fpin);
184
185 key = PEM_read_RSA_PUBKEY(fpin, NULL, NULL, NULL);
186 if (key) {
187 ret = print_public_rsa_key(fpout, key);
188 RSA_free(key);
189
190 return ret;
191 }
192
193 /* Implement parsing of input stream containing
194 * private or public "plainrsa" formatted text.
195 * Convert the result to PEM formatted output.
196 *
197 * This seemingly needs manual use of prsaparse().
198 * An expert ought to do this. */
199
200 fprintf(stderr, "convert_rsa_key: %s\n", "Only conversion from PEM at this time");
201 return -1;
202 }
203
204 int
gen_rsa_key(FILE * fp,size_t bits,unsigned long exp)205 gen_rsa_key(FILE *fp, size_t bits, unsigned long exp)
206 {
207 int ret;
208 RSA *key;
209 BIGNUM *e;
210
211 key = RSA_new();
212 e = BN_new();
213 BN_set_word(e, exp);
214
215 if (1 != RSA_generate_key_ex(key, bits, e, NULL)) {
216 fprintf(stderr, "RSA_generate_key(): %s\n", eay_strerror());
217 return -1;
218 }
219
220 ret = print_rsa_key(fp, key);
221 RSA_free(key);
222
223 return ret;
224 }
225
226 int
main(int argc,char * argv[])227 main (int argc, char *argv[])
228 {
229 FILE *fp = stdout, *fpin = NULL;
230 size_t bits = 1024;
231 unsigned int pubexp = DEFAULT_PUBEXP;
232 struct stat st;
233 extern char *optarg;
234 extern int optind;
235 int c, fd = -1, fdin = -1;
236 char *fname = NULL, *finput = NULL;
237
238 while ((c = getopt(argc, argv, "e:b:f:i:h")) != -1)
239 switch (c) {
240 case 'e':
241 pubexp = (unsigned int)strtoul(optarg, NULL, 0);
242 break;
243 case 'b':
244 bits = atoi(optarg);
245 break;
246 case 'f':
247 fname = optarg;
248 break;
249 case 'i':
250 finput = optarg;
251 break;
252 case 'h':
253 default:
254 usage(argv[0]);
255 }
256
257 if (fname) {
258 umask(0077);
259 /* Restrictive access due to private key material. */
260 fd = open(fname, O_WRONLY | O_CREAT | O_EXCL | O_NOFOLLOW, S_IRUSR | S_IWUSR);
261 if (fd < 0) {
262 if (errno == EEXIST)
263 fprintf(stderr, "%s: file exists! Please use a different name.\n", fname);
264 else
265 fprintf(stderr, "%s: %s\n", fname, strerror(errno));
266 exit(1);
267 }
268 fp = fdopen(fd, "w");
269 if (fp == NULL) {
270 fprintf(stderr, "%s: %s\n", fname, strerror(errno));
271 close(fd);
272 exit(1);
273 }
274 }
275
276 if (finput) {
277 /* Restrictive access once more. Do not be fooled by a link. */
278 fdin = open(finput, O_RDONLY | O_NOFOLLOW);
279 if (fdin < 0) {
280 if (errno == ELOOP)
281 fprintf(stderr, "%s: file is a link. Discarded for security.\n", fname);
282 if (fp)
283 fclose(fp);
284 exit(1);
285 }
286 fpin = fdopen(fdin, "r");
287 if (fpin == NULL) {
288 fprintf(stderr, "%s: %s\n", fname, strerror(errno));
289 close(fdin);
290 if (fp)
291 fclose(fp);
292 exit(1);
293 }
294
295 }
296
297 ploginit();
298 eay_init();
299
300 if (fpin)
301 convert_rsa_key(fp, fpin);
302 else
303 gen_rsa_key(fp, bits, pubexp);
304
305 fclose(fp);
306 if (fpin)
307 fclose(fpin);
308
309 return 0;
310 }
311