xref: /freebsd/crypto/openssl/apps/gendsa.c (revision 1da7f3f6f72b2245e458fc7195733268ae4a1136)
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/dsa.h>
22 #include <openssl/x509.h>
23 #include <openssl/pem.h>
24 
25 typedef enum OPTION_choice {
26     OPT_COMMON,
27     OPT_OUT, OPT_PASSOUT, OPT_ENGINE, OPT_CIPHER, OPT_VERBOSE,
28     OPT_R_ENUM, OPT_PROV_ENUM
29 } OPTION_CHOICE;
30 
31 const OPTIONS gendsa_options[] = {
32     {OPT_HELP_STR, 1, '-', "Usage: %s [options] dsaparam-file\n"},
33 
34     OPT_SECTION("General"),
35     {"help", OPT_HELP, '-', "Display this summary"},
36 #ifndef OPENSSL_NO_ENGINE
37     {"engine", OPT_ENGINE, 's', "Use engine, possibly a hardware device"},
38 #endif
39 
40     OPT_SECTION("Output"),
41     {"out", OPT_OUT, '>', "Output the key to the specified file"},
42     {"passout", OPT_PASSOUT, 's', "Output file pass phrase source"},
43     OPT_R_OPTIONS,
44     OPT_PROV_OPTIONS,
45     {"", OPT_CIPHER, '-', "Encrypt the output with any supported cipher"},
46     {"verbose", OPT_VERBOSE, '-', "Verbose output"},
47 
48     OPT_PARAMETERS(),
49     {"dsaparam-file", 0, 0, "File containing DSA parameters"},
50     {NULL}
51 };
52 
53 int gendsa_main(int argc, char **argv)
54 {
55     ENGINE *e = NULL;
56     BIO *out = NULL, *in = NULL;
57     EVP_PKEY *pkey = NULL;
58     EVP_PKEY_CTX *ctx = NULL;
59     EVP_CIPHER *enc = NULL;
60     char *dsaparams = NULL, *ciphername = NULL;
61     char *outfile = NULL, *passoutarg = NULL, *passout = NULL, *prog;
62     OPTION_CHOICE o;
63     int ret = 1, private = 0, verbose = 0, nbits;
64 
65     prog = opt_init(argc, argv, gendsa_options);
66     while ((o = opt_next()) != OPT_EOF) {
67         switch (o) {
68         case OPT_EOF:
69         case OPT_ERR:
70  opthelp:
71             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
72             goto end;
73         case OPT_HELP:
74             ret = 0;
75             opt_help(gendsa_options);
76             goto end;
77         case OPT_OUT:
78             outfile = opt_arg();
79             break;
80         case OPT_PASSOUT:
81             passoutarg = opt_arg();
82             break;
83         case OPT_ENGINE:
84             e = setup_engine(opt_arg(), 0);
85             break;
86         case OPT_R_CASES:
87             if (!opt_rand(o))
88                 goto end;
89             break;
90         case OPT_PROV_CASES:
91             if (!opt_provider(o))
92                 goto end;
93             break;
94         case OPT_CIPHER:
95             ciphername = opt_unknown();
96             break;
97         case OPT_VERBOSE:
98             verbose = 1;
99             break;
100         }
101     }
102 
103     /* One argument, the params file. */
104     argc = opt_num_rest();
105     argv = opt_rest();
106     if (argc != 1)
107         goto opthelp;
108     dsaparams = argv[0];
109 
110     if (!app_RAND_load())
111         goto end;
112 
113     if (ciphername != NULL) {
114         if (!opt_cipher(ciphername, &enc))
115             goto end;
116     }
117     private = 1;
118 
119     if (!app_passwd(NULL, passoutarg, NULL, &passout)) {
120         BIO_printf(bio_err, "Error getting password\n");
121         goto end;
122     }
123 
124     pkey = load_keyparams(dsaparams, FORMAT_UNDEF, 1, "DSA", "DSA parameters");
125 
126     out = bio_open_owner(outfile, FORMAT_PEM, private);
127     if (out == NULL)
128         goto end2;
129 
130     nbits = EVP_PKEY_get_bits(pkey);
131     if (nbits > OPENSSL_DSA_MAX_MODULUS_BITS)
132         BIO_printf(bio_err,
133                    "Warning: It is not recommended to use more than %d bit for DSA keys.\n"
134                    "         Your key size is %d! Larger key size may behave not as expected.\n",
135                    OPENSSL_DSA_MAX_MODULUS_BITS, EVP_PKEY_get_bits(pkey));
136 
137     ctx = EVP_PKEY_CTX_new_from_pkey(app_get0_libctx(), pkey, app_get0_propq());
138     if (ctx == NULL) {
139         BIO_printf(bio_err, "unable to create PKEY context\n");
140         goto end;
141     }
142     EVP_PKEY_free(pkey);
143     pkey = NULL;
144     if (EVP_PKEY_keygen_init(ctx) <= 0) {
145         BIO_printf(bio_err, "unable to set up for key generation\n");
146         goto end;
147     }
148     pkey = app_keygen(ctx, "DSA", nbits, verbose);
149     if (pkey == NULL)
150         goto end;
151 
152     assert(private);
153     if (!PEM_write_bio_PrivateKey(out, pkey, enc, NULL, 0, NULL, passout)) {
154         BIO_printf(bio_err, "unable to output generated key\n");
155         goto end;
156     }
157     ret = 0;
158  end:
159     if (ret != 0)
160         ERR_print_errors(bio_err);
161  end2:
162     BIO_free(in);
163     BIO_free_all(out);
164     EVP_PKEY_free(pkey);
165     EVP_PKEY_CTX_free(ctx);
166     EVP_CIPHER_free(enc);
167     release_engine(e);
168     OPENSSL_free(passout);
169     return ret;
170 }
171