1 /*
2 * Copyright 1995-2023 The OpenSSL Project Authors. All Rights Reserved.
3 *
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
8 */
9
10 #include <openssl/opensslconf.h>
11
12 #include <stdio.h>
13 #include <string.h>
14 #include <sys/types.h>
15 #include <sys/stat.h>
16 #include "apps.h"
17 #include "progs.h"
18 #include <openssl/bio.h>
19 #include <openssl/err.h>
20 #include <openssl/bn.h>
21 #include <openssl/rsa.h>
22 #include <openssl/evp.h>
23 #include <openssl/x509.h>
24 #include <openssl/pem.h>
25 #include <openssl/rand.h>
26
27 #define DEFBITS 2048
28 #define DEFPRIMES 2
29
30 static int verbose = 0;
31
32 static int genrsa_cb(EVP_PKEY_CTX *ctx);
33
34 typedef enum OPTION_choice {
35 OPT_COMMON,
36 #ifndef OPENSSL_NO_DEPRECATED_3_0
37 OPT_3,
38 #endif
39 OPT_F4, OPT_ENGINE,
40 OPT_OUT, OPT_PASSOUT, OPT_CIPHER, OPT_PRIMES, OPT_VERBOSE,
41 OPT_R_ENUM, OPT_PROV_ENUM, OPT_TRADITIONAL
42 } OPTION_CHOICE;
43
44 const OPTIONS genrsa_options[] = {
45 {OPT_HELP_STR, 1, '-', "Usage: %s [options] numbits\n"},
46
47 OPT_SECTION("General"),
48 {"help", OPT_HELP, '-', "Display this summary"},
49 #ifndef OPENSSL_NO_ENGINE
50 {"engine", OPT_ENGINE, 's', "Use engine, possibly a hardware device"},
51 #endif
52
53 OPT_SECTION("Input"),
54 #ifndef OPENSSL_NO_DEPRECATED_3_0
55 {"3", OPT_3, '-', "(deprecated) Use 3 for the E value"},
56 #endif
57 {"F4", OPT_F4, '-', "Use the Fermat number F4 (0x10001) for the E value"},
58 {"f4", OPT_F4, '-', "Use the Fermat number F4 (0x10001) for the E value"},
59
60 OPT_SECTION("Output"),
61 {"out", OPT_OUT, '>', "Output the key to specified file"},
62 {"passout", OPT_PASSOUT, 's', "Output file pass phrase source"},
63 {"primes", OPT_PRIMES, 'p', "Specify number of primes"},
64 {"verbose", OPT_VERBOSE, '-', "Verbose output"},
65 {"traditional", OPT_TRADITIONAL, '-',
66 "Use traditional format for private keys"},
67 {"", OPT_CIPHER, '-', "Encrypt the output with any supported cipher"},
68
69 OPT_R_OPTIONS,
70 OPT_PROV_OPTIONS,
71
72 OPT_PARAMETERS(),
73 {"numbits", 0, 0, "Size of key in bits"},
74 {NULL}
75 };
76
genrsa_main(int argc,char ** argv)77 int genrsa_main(int argc, char **argv)
78 {
79 BN_GENCB *cb = BN_GENCB_new();
80 ENGINE *eng = NULL;
81 BIGNUM *bn = BN_new();
82 BIO *out = NULL;
83 EVP_PKEY *pkey = NULL;
84 EVP_PKEY_CTX *ctx = NULL;
85 EVP_CIPHER *enc = NULL;
86 int ret = 1, num = DEFBITS, private = 0, primes = DEFPRIMES;
87 unsigned long f4 = RSA_F4;
88 char *outfile = NULL, *passoutarg = NULL, *passout = NULL;
89 char *prog, *hexe, *dece, *ciphername = NULL;
90 OPTION_CHOICE o;
91 int traditional = 0;
92
93 if (bn == NULL || cb == NULL)
94 goto end;
95
96 prog = opt_init(argc, argv, genrsa_options);
97 while ((o = opt_next()) != OPT_EOF) {
98 switch (o) {
99 case OPT_EOF:
100 case OPT_ERR:
101 opthelp:
102 BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
103 goto end;
104 case OPT_HELP:
105 ret = 0;
106 opt_help(genrsa_options);
107 goto end;
108 #ifndef OPENSSL_NO_DEPRECATED_3_0
109 case OPT_3:
110 f4 = RSA_3;
111 break;
112 #endif
113 case OPT_F4:
114 f4 = RSA_F4;
115 break;
116 case OPT_OUT:
117 outfile = opt_arg();
118 break;
119 case OPT_ENGINE:
120 eng = setup_engine(opt_arg(), 0);
121 break;
122 case OPT_R_CASES:
123 if (!opt_rand(o))
124 goto end;
125 break;
126 case OPT_PROV_CASES:
127 if (!opt_provider(o))
128 goto end;
129 break;
130 case OPT_PASSOUT:
131 passoutarg = opt_arg();
132 break;
133 case OPT_CIPHER:
134 ciphername = opt_unknown();
135 break;
136 case OPT_PRIMES:
137 primes = opt_int_arg();
138 break;
139 case OPT_VERBOSE:
140 verbose = 1;
141 break;
142 case OPT_TRADITIONAL:
143 traditional = 1;
144 break;
145 }
146 }
147
148 /* One optional argument, the bitsize. */
149 argc = opt_num_rest();
150 argv = opt_rest();
151
152 if (argc == 1) {
153 if (!opt_int(argv[0], &num) || num <= 0)
154 goto end;
155 if (num > OPENSSL_RSA_MAX_MODULUS_BITS)
156 BIO_printf(bio_err,
157 "Warning: It is not recommended to use more than %d bit for RSA keys.\n"
158 " Your key size is %d! Larger key size may behave not as expected.\n",
159 OPENSSL_RSA_MAX_MODULUS_BITS, num);
160 } else if (argc > 0) {
161 BIO_printf(bio_err, "Extra arguments given.\n");
162 goto opthelp;
163 }
164
165 if (!app_RAND_load())
166 goto end;
167
168 private = 1;
169 if (ciphername != NULL) {
170 if (!opt_cipher(ciphername, &enc))
171 goto end;
172 }
173 if (!app_passwd(NULL, passoutarg, NULL, &passout)) {
174 BIO_printf(bio_err, "Error getting password\n");
175 goto end;
176 }
177
178 out = bio_open_owner(outfile, FORMAT_PEM, private);
179 if (out == NULL)
180 goto end;
181
182 if (!init_gen_str(&ctx, "RSA", eng, 0, app_get0_libctx(),
183 app_get0_propq()))
184 goto end;
185
186 EVP_PKEY_CTX_set_cb(ctx, genrsa_cb);
187 EVP_PKEY_CTX_set_app_data(ctx, bio_err);
188
189 if (EVP_PKEY_CTX_set_rsa_keygen_bits(ctx, num) <= 0) {
190 BIO_printf(bio_err, "Error setting RSA length\n");
191 goto end;
192 }
193 if (!BN_set_word(bn, f4)) {
194 BIO_printf(bio_err, "Error allocating RSA public exponent\n");
195 goto end;
196 }
197 if (EVP_PKEY_CTX_set1_rsa_keygen_pubexp(ctx, bn) <= 0) {
198 BIO_printf(bio_err, "Error setting RSA public exponent\n");
199 goto end;
200 }
201 if (EVP_PKEY_CTX_set_rsa_keygen_primes(ctx, primes) <= 0) {
202 BIO_printf(bio_err, "Error setting number of primes\n");
203 goto end;
204 }
205 pkey = app_keygen(ctx, "RSA", num, verbose);
206 if (pkey == NULL)
207 goto end;
208
209 if (verbose) {
210 BIGNUM *e = NULL;
211
212 /* Every RSA key has an 'e' */
213 EVP_PKEY_get_bn_param(pkey, "e", &e);
214 if (e == NULL) {
215 BIO_printf(bio_err, "Error cannot access RSA e\n");
216 goto end;
217 }
218 hexe = BN_bn2hex(e);
219 dece = BN_bn2dec(e);
220 if (hexe && dece) {
221 BIO_printf(bio_err, "e is %s (0x%s)\n", dece, hexe);
222 }
223 OPENSSL_free(hexe);
224 OPENSSL_free(dece);
225 BN_free(e);
226 }
227 if (traditional) {
228 if (!PEM_write_bio_PrivateKey_traditional(out, pkey, enc, NULL, 0,
229 NULL, passout))
230 goto end;
231 } else {
232 if (!PEM_write_bio_PrivateKey(out, pkey, enc, NULL, 0, NULL, passout))
233 goto end;
234 }
235
236 ret = 0;
237 end:
238 BN_free(bn);
239 BN_GENCB_free(cb);
240 EVP_PKEY_CTX_free(ctx);
241 EVP_PKEY_free(pkey);
242 EVP_CIPHER_free(enc);
243 BIO_free_all(out);
244 release_engine(eng);
245 OPENSSL_free(passout);
246 if (ret != 0)
247 ERR_print_errors(bio_err);
248 return ret;
249 }
250
genrsa_cb(EVP_PKEY_CTX * ctx)251 static int genrsa_cb(EVP_PKEY_CTX *ctx)
252 {
253 char c = '*';
254 BIO *b = EVP_PKEY_CTX_get_app_data(ctx);
255 int p = EVP_PKEY_CTX_get_keygen_info(ctx, 0);
256
257 if (!verbose)
258 return 1;
259
260 if (p == 0)
261 c = '.';
262 if (p == 1)
263 c = '+';
264 if (p == 2)
265 c = '*';
266 if (p == 3)
267 c = '\n';
268 BIO_write(b, &c, 1);
269 (void)BIO_flush(b);
270 return 1;
271 }
272