apps/dsaparam.c

   1 /*
   2  * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
   3  *
   4  * Licensed under the OpenSSL license (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 #ifdef OPENSSL_NO_DSA
  12 NON_EMPTY_TRANSLATION_UNIT
  13 #else
  14
  15 # include <stdio.h>
  16 # include <stdlib.h>
  17 # include <time.h>
  18 # include <string.h>
  19 # include "apps.h"
  20 # include "progs.h"
  21 # include <openssl/bio.h>
  22 # include <openssl/err.h>
  23 # include <openssl/bn.h>
  24 # include <openssl/dsa.h>
  25 # include <openssl/x509.h>
  26 # include <openssl/pem.h>
  27
  28 static int dsa_cb(int p, int n, BN_GENCB *cb);
  29
  30 typedef enum OPTION_choice {
  31     OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,
  32     OPT_INFORM, OPT_OUTFORM, OPT_IN, OPT_OUT, OPT_TEXT, OPT_C,
  33     OPT_NOOUT, OPT_GENKEY, OPT_ENGINE, OPT_R_ENUM
  34 } OPTION_CHOICE;
  35
  36 const OPTIONS dsaparam_options[] = {
  37     {"help", OPT_HELP, '-', "Display this summary"},
  38     {"inform", OPT_INFORM, 'F', "Input format - DER or PEM"},
  39     {"in", OPT_IN, '<', "Input file"},
  40     {"outform", OPT_OUTFORM, 'F', "Output format - DER or PEM"},
  41     {"out", OPT_OUT, '>', "Output file"},
  42     {"text", OPT_TEXT, '-', "Print as text"},
  43     {"C", OPT_C, '-', "Output C code"},
  44     {"noout", OPT_NOOUT, '-', "No output"},
  45     {"genkey", OPT_GENKEY, '-', "Generate a DSA key"},
  46     OPT_R_OPTIONS,
  47 # ifndef OPENSSL_NO_ENGINE
  48     {"engine", OPT_ENGINE, 's', "Use engine e, possibly a hardware device"},
  49 # endif
  50     {NULL}
  51 };
  52
  53 int dsaparam_main(int argc, char **argv)
  54 {
  55     ENGINE *e = NULL;
  56     DSA *dsa = NULL;
  57     BIO *in = NULL, *out = NULL;
  58     BN_GENCB *cb = NULL;
  59     int numbits = -1, num = 0, genkey = 0;
  60     int informat = FORMAT_PEM, outformat = FORMAT_PEM, noout = 0, C = 0;
  61     int ret = 1, i, text = 0, private = 0;
  62     char *infile = NULL, *outfile = NULL, *prog;
  63     OPTION_CHOICE o;
  64
  65     prog = opt_init(argc, argv, dsaparam_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             opt_help(dsaparam_options);
  75             ret = 0;
  76             goto end;
  77         case OPT_INFORM:
  78             if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &informat))
  79                 goto opthelp;
  80             break;
  81         case OPT_IN:
  82             infile = opt_arg();
  83             break;
  84         case OPT_OUTFORM:
  85             if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &outformat))
  86                 goto opthelp;
  87             break;
  88         case OPT_OUT:
  89             outfile = opt_arg();
  90             break;
  91         case OPT_ENGINE:
  92             e = setup_engine(opt_arg(), 0);
  93             break;
  94         case OPT_TEXT:
  95             text = 1;
  96             break;
  97         case OPT_C:
  98             C = 1;
  99             break;
 100         case OPT_GENKEY:
 101             genkey = 1;
 102             break;
 103         case OPT_R_CASES:
 104             if (!opt_rand(o))
 105                 goto end;
 106             break;
 107         case OPT_NOOUT:
 108             noout = 1;
 109             break;
 110         }
 111     }
 112     argc = opt_num_rest();
 113     argv = opt_rest();
 114
 115     if (argc == 1) {
 116         if (!opt_int(argv[0], &num) || num < 0)
 117             goto end;
 118         /* generate a key */
 119         numbits = num;
 120     }
 121     private = genkey ? 1 : 0;
 122
 123     in = bio_open_default(infile, 'r', informat);
 124     if (in == NULL)
 125         goto end;
 126     out = bio_open_owner(outfile, outformat, private);
 127     if (out == NULL)
 128         goto end;
 129
 130     if (numbits > 0) {
 131         if (numbits > 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, numbits);
 136
 137         cb = BN_GENCB_new();
 138         if (cb == NULL) {
 139             BIO_printf(bio_err, "Error allocating BN_GENCB object\n");
 140             goto end;
 141         }
 142         BN_GENCB_set(cb, dsa_cb, bio_err);
 143         dsa = DSA_new();
 144         if (dsa == NULL) {
 145             BIO_printf(bio_err, "Error allocating DSA object\n");
 146             goto end;
 147         }
 148         BIO_printf(bio_err, "Generating DSA parameters, %d bit long prime\n",
 149                    num);
 150         BIO_printf(bio_err, "This could take some time\n");
 151         if (!DSA_generate_parameters_ex(dsa, num, NULL, 0, NULL, NULL, cb)) {
 152             ERR_print_errors(bio_err);
 153             BIO_printf(bio_err, "Error, DSA key generation failed\n");
 154             goto end;
 155         }
 156     } else if (informat == FORMAT_ASN1) {
 157         dsa = d2i_DSAparams_bio(in, NULL);
 158     } else {
 159         dsa = PEM_read_bio_DSAparams(in, NULL, NULL, NULL);
 160     }
 161     if (dsa == NULL) {
 162         BIO_printf(bio_err, "unable to load DSA parameters\n");
 163         ERR_print_errors(bio_err);
 164         goto end;
 165     }
 166
 167     if (text) {
 168         DSAparams_print(out, dsa);
 169     }
 170
 171     if (C) {
 172         const BIGNUM *p = NULL, *q = NULL, *g = NULL;
 173         unsigned char *data;
 174         int len, bits_p;
 175
 176         DSA_get0_pqg(dsa, &p, &q, &g);
 177         len = BN_num_bytes(p);
 178         bits_p = BN_num_bits(p);
 179
 180         data = app_malloc(len + 20, "BN space");
 181
 182         BIO_printf(bio_out, "static DSA *get_dsa%d(void)\n{\n", bits_p);
 183         print_bignum_var(bio_out, p, "dsap", bits_p, data);
 184         print_bignum_var(bio_out, q, "dsaq", bits_p, data);
 185         print_bignum_var(bio_out, g, "dsag", bits_p, data);
 186         BIO_printf(bio_out, "    DSA *dsa = DSA_new();\n"
 187                             "    BIGNUM *p, *q, *g;\n"
 188                             "\n");
 189         BIO_printf(bio_out, "    if (dsa == NULL)\n"
 190                             "        return NULL;\n");
 191         BIO_printf(bio_out, "    if (!DSA_set0_pqg(dsa, p = BN_bin2bn(dsap_%d, sizeof(dsap_%d), NULL),\n",
 192                    bits_p, bits_p);
 193         BIO_printf(bio_out, "                           q = BN_bin2bn(dsaq_%d, sizeof(dsaq_%d), NULL),\n",
 194                    bits_p, bits_p);
 195         BIO_printf(bio_out, "                           g = BN_bin2bn(dsag_%d, sizeof(dsag_%d), NULL))) {\n",
 196                    bits_p, bits_p);
 197         BIO_printf(bio_out, "        DSA_free(dsa);\n"
 198                             "        BN_free(p);\n"
 199                             "        BN_free(q);\n"
 200                             "        BN_free(g);\n"
 201                             "        return NULL;\n"
 202                             "    }\n"
 203                             "    return dsa;\n}\n");
 204         OPENSSL_free(data);
 205     }
 206
 207     if (outformat == FORMAT_ASN1 && genkey)
 208         noout = 1;
 209
 210     if (!noout) {
 211         if (outformat == FORMAT_ASN1)
 212             i = i2d_DSAparams_bio(out, dsa);
 213         else
 214             i = PEM_write_bio_DSAparams(out, dsa);
 215         if (!i) {
 216             BIO_printf(bio_err, "unable to write DSA parameters\n");
 217             ERR_print_errors(bio_err);
 218             goto end;
 219         }
 220     }
 221     if (genkey) {
 222         DSA *dsakey;
 223
 224         if ((dsakey = DSAparams_dup(dsa)) == NULL)
 225             goto end;
 226         if (!DSA_generate_key(dsakey)) {
 227             ERR_print_errors(bio_err);
 228             DSA_free(dsakey);
 229             goto end;
 230         }
 231         assert(private);
 232         if (outformat == FORMAT_ASN1)
 233             i = i2d_DSAPrivateKey_bio(out, dsakey);
 234         else
 235             i = PEM_write_bio_DSAPrivateKey(out, dsakey, NULL, NULL, 0, NULL,
 236                                             NULL);
 237         DSA_free(dsakey);
 238     }
 239     ret = 0;
 240  end:
 241     BN_GENCB_free(cb);
 242     BIO_free(in);
 243     BIO_free_all(out);
 244     DSA_free(dsa);
 245     release_engine(e);
 246     return ret;
 247 }
 248
 249 static int dsa_cb(int p, int n, BN_GENCB *cb)
 250 {
 251     static const char symbols[] = ".+*\n";
 252     char c = (p >= 0 && (size_t)p < sizeof(symbols) - 1) ? symbols[p] : '?';
 253
 254     BIO_write(BN_GENCB_get_arg(cb), &c, 1);
 255     (void)BIO_flush(BN_GENCB_get_arg(cb));
 256     return 1;
 257 }
 258 #endif