apps/dsaparam.c

   1 /*
   2  * Copyright 1995-2021 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 <stdlib.h>
  14 #include <time.h>
  15 #include <string.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 static int verbose = 0;
  26
  27 static int gendsa_cb(EVP_PKEY_CTX *ctx);
  28
  29 typedef enum OPTION_choice {
  30     OPT_COMMON,
  31     OPT_INFORM, OPT_OUTFORM, OPT_IN, OPT_OUT, OPT_TEXT,
  32     OPT_NOOUT, OPT_GENKEY, OPT_ENGINE, OPT_VERBOSE,
  33     OPT_R_ENUM, OPT_PROV_ENUM
  34 } OPTION_CHOICE;
  35
  36 const OPTIONS dsaparam_options[] = {
  37     {OPT_HELP_STR, 1, '-', "Usage: %s [options] [numbits]\n"},
  38
  39     OPT_SECTION("General"),
  40     {"help", OPT_HELP, '-', "Display this summary"},
  41 #ifndef OPENSSL_NO_ENGINE
  42     {"engine", OPT_ENGINE, 's', "Use engine e, possibly a hardware device"},
  43 #endif
  44
  45     OPT_SECTION("Input"),
  46     {"in", OPT_IN, '<', "Input file"},
  47     {"inform", OPT_INFORM, 'F', "Input format - DER or PEM"},
  48
  49     OPT_SECTION("Output"),
  50     {"out", OPT_OUT, '>', "Output file"},
  51     {"outform", OPT_OUTFORM, 'F', "Output format - DER or PEM"},
  52     {"text", OPT_TEXT, '-', "Print as text"},
  53     {"noout", OPT_NOOUT, '-', "No output"},
  54     {"verbose", OPT_VERBOSE, '-', "Verbose output"},
  55     {"genkey", OPT_GENKEY, '-', "Generate a DSA key"},
  56
  57     OPT_R_OPTIONS,
  58     OPT_PROV_OPTIONS,
  59
  60     OPT_PARAMETERS(),
  61     {"numbits", 0, 0, "Number of bits if generating parameters (optional)"},
  62     {NULL}
  63 };
  64
  65 int dsaparam_main(int argc, char **argv)
  66 {
  67     ENGINE *e = NULL;
  68     BIO *out = NULL;
  69     EVP_PKEY *params = NULL, *pkey = NULL;
  70     EVP_PKEY_CTX *ctx = NULL;
  71     int numbits = -1, num = 0, genkey = 0;
  72     int informat = FORMAT_PEM, outformat = FORMAT_PEM, noout = 0;
  73     int ret = 1, i, text = 0, private = 0;
  74     char *infile = NULL, *outfile = NULL, *prog;
  75     OPTION_CHOICE o;
  76
  77     prog = opt_init(argc, argv, dsaparam_options);
  78     while ((o = opt_next()) != OPT_EOF) {
  79         switch (o) {
  80         case OPT_EOF:
  81         case OPT_ERR:
  82  opthelp:
  83             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
  84             goto end;
  85         case OPT_HELP:
  86             opt_help(dsaparam_options);
  87             ret = 0;
  88             goto end;
  89         case OPT_INFORM:
  90             if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &informat))
  91                 goto opthelp;
  92             break;
  93         case OPT_IN:
  94             infile = opt_arg();
  95             break;
  96         case OPT_OUTFORM:
  97             if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &outformat))
  98                 goto opthelp;
  99             break;
 100         case OPT_OUT:
 101             outfile = opt_arg();
 102             break;
 103         case OPT_ENGINE:
 104             e = setup_engine(opt_arg(), 0);
 105             break;
 106         case OPT_TEXT:
 107             text = 1;
 108             break;
 109         case OPT_GENKEY:
 110             genkey = 1;
 111             break;
 112         case OPT_R_CASES:
 113             if (!opt_rand(o))
 114                 goto end;
 115             break;
 116         case OPT_PROV_CASES:
 117             if (!opt_provider(o))
 118                 goto end;
 119             break;
 120         case OPT_NOOUT:
 121             noout = 1;
 122             break;
 123         case OPT_VERBOSE:
 124             verbose = 1;
 125             break;
 126         }
 127     }
 128
 129     /* Optional arg is bitsize. */
 130     argc = opt_num_rest();
 131     argv = opt_rest();
 132     if (argc == 1) {
 133         if (!opt_int(argv[0], &num) || num < 0)
 134             goto opthelp;
 135     } else if (argc != 0) {
 136         goto opthelp;
 137     }
 138     if (!app_RAND_load())
 139         goto end;
 140
 141     /* generate a key */
 142     numbits = num;
 143     private = genkey ? 1 : 0;
 144
 145     out = bio_open_owner(outfile, outformat, private);
 146     if (out == NULL)
 147         goto end;
 148
 149     ctx = EVP_PKEY_CTX_new_from_name(NULL, "DSA", NULL);
 150     if (ctx == NULL) {
 151         BIO_printf(bio_err,
 152                    "Error, DSA parameter generation context allocation failed\n");
 153         goto end;
 154     }
 155     if (numbits > 0) {
 156         if (numbits > OPENSSL_DSA_MAX_MODULUS_BITS)
 157             BIO_printf(bio_err,
 158                        "Warning: It is not recommended to use more than %d bit for DSA keys.\n"
 159                        "         Your key size is %d! Larger key size may behave not as expected.\n",
 160                        OPENSSL_DSA_MAX_MODULUS_BITS, numbits);
 161
 162         EVP_PKEY_CTX_set_cb(ctx, gendsa_cb);
 163         EVP_PKEY_CTX_set_app_data(ctx, bio_err);
 164         if (verbose) {
 165             BIO_printf(bio_err, "Generating DSA parameters, %d bit long prime\n",
 166                        num);
 167             BIO_printf(bio_err, "This could take some time\n");
 168         }
 169         if (EVP_PKEY_paramgen_init(ctx) <= 0) {
 170             BIO_printf(bio_err,
 171                        "Error, DSA key generation paramgen init failed\n");
 172             goto end;
 173         }
 174         if (!EVP_PKEY_CTX_set_dsa_paramgen_bits(ctx, num)) {
 175             BIO_printf(bio_err,
 176                        "Error, DSA key generation setting bit length failed\n");
 177             goto end;
 178         }
 179         if (EVP_PKEY_paramgen(ctx, &params) <= 0) {
 180             BIO_printf(bio_err, "Error, DSA key generation failed\n");
 181             goto end;
 182         }
 183     } else {
 184         params = load_keyparams(infile, 1, "DSA", "DSA parameters");
 185     }
 186     if (params == NULL) {
 187         /* Error message should already have been displayed */
 188         goto end;
 189     }
 190
 191     if (text) {
 192         EVP_PKEY_print_params(out, params, 0, NULL);
 193     }
 194
 195     if (outformat == FORMAT_ASN1 && genkey)
 196         noout = 1;
 197
 198     if (!noout) {
 199         if (outformat == FORMAT_ASN1)
 200             i = i2d_KeyParams_bio(out, params);
 201         else
 202             i = PEM_write_bio_Parameters(out, params);
 203         if (!i) {
 204             BIO_printf(bio_err, "Error, unable to write DSA parameters\n");
 205             goto end;
 206         }
 207     }
 208     if (genkey) {
 209         EVP_PKEY_CTX_free(ctx);
 210         ctx = EVP_PKEY_CTX_new(params, NULL);
 211         if (ctx == NULL) {
 212             BIO_printf(bio_err,
 213                        "Error, DSA key generation context allocation failed\n");
 214             goto end;
 215         }
 216         if (!EVP_PKEY_keygen_init(ctx)) {
 217             BIO_printf(bio_err,
 218                        "Error, unable to initialise for key generation\n");
 219             goto end;
 220         }
 221         if (!EVP_PKEY_keygen(ctx, &pkey)) {
 222             BIO_printf(bio_err, "Error, unable to generate key\n");
 223             goto end;
 224         }
 225         assert(private);
 226         if (outformat == FORMAT_ASN1)
 227             i = i2d_PrivateKey_bio(out, pkey);
 228         else
 229             i = PEM_write_bio_PrivateKey(out, pkey, NULL, NULL, 0, NULL, NULL);
 230     }
 231     ret = 0;
 232  end:
 233     if (ret != 0)
 234         ERR_print_errors(bio_err);
 235     BIO_free_all(out);
 236     EVP_PKEY_CTX_free(ctx);
 237     EVP_PKEY_free(pkey);
 238     EVP_PKEY_free(params);
 239     release_engine(e);
 240     return ret;
 241 }
 242
 243 static int gendsa_cb(EVP_PKEY_CTX *ctx)
 244 {
 245     static const char symbols[] = ".+*\n";
 246     int p;
 247     char c;
 248     BIO *b;
 249
 250     if (!verbose)
 251         return 1;
 252
 253     b = EVP_PKEY_CTX_get_app_data(ctx);
 254     p = EVP_PKEY_CTX_get_keygen_info(ctx, 0);
 255     c = (p >= 0 && (size_t)p < sizeof(symbols) - 1) ? symbols[p] : '?';
 256
 257     BIO_write(b, &c, 1);
 258     (void)BIO_flush(b);
 259     return 1;
 260 }