apps/dsaparam.c

   1 /*
   2  * Copyright 1995-2018 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 #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 verbose = 0;
  29
  30 static int dsa_cb(int p, int n, BN_GENCB *cb);
  31
  32 typedef enum OPTION_choice {
  33     OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,
  34     OPT_INFORM, OPT_OUTFORM, OPT_IN, OPT_OUT, OPT_TEXT, OPT_C,
  35     OPT_NOOUT, OPT_GENKEY, OPT_ENGINE, OPT_VERBOSE,
  36     OPT_R_ENUM
  37 } OPTION_CHOICE;
  38
  39 const OPTIONS dsaparam_options[] = {
  40     {"help", OPT_HELP, '-', "Display this summary"},
  41     {"inform", OPT_INFORM, 'F', "Input format - DER or PEM"},
  42     {"in", OPT_IN, '<', "Input file"},
  43     {"outform", OPT_OUTFORM, 'F', "Output format - DER or PEM"},
  44     {"out", OPT_OUT, '>', "Output file"},
  45     {"text", OPT_TEXT, '-', "Print as text"},
  46     {"C", OPT_C, '-', "Output C code"},
  47     {"noout", OPT_NOOUT, '-', "No output"},
  48     {"genkey", OPT_GENKEY, '-', "Generate a DSA key"},
  49     OPT_R_OPTIONS,
  50 # ifndef OPENSSL_NO_ENGINE
  51     {"engine", OPT_ENGINE, 's', "Use engine e, possibly a hardware device"},
  52 # endif
  53     {"verbose", OPT_VERBOSE, '-', "Verbose output"},
  54     {NULL}
  55 };
  56
  57 int dsaparam_main(int argc, char **argv)
  58 {
  59     ENGINE *e = NULL;
  60     DSA *dsa = NULL;
  61     BIO *in = NULL, *out = NULL;
  62     BN_GENCB *cb = NULL;
  63     int numbits = -1, num = 0, genkey = 0;
  64     int informat = FORMAT_PEM, outformat = FORMAT_PEM, noout = 0, C = 0;
  65     int ret = 1, i, text = 0, private = 0;
  66     char *infile = NULL, *outfile = NULL, *prog;
  67     OPTION_CHOICE o;
  68
  69     prog = opt_init(argc, argv, dsaparam_options);
  70     while ((o = opt_next()) != OPT_EOF) {
  71         switch (o) {
  72         case OPT_EOF:
  73         case OPT_ERR:
  74  opthelp:
  75             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
  76             goto end;
  77         case OPT_HELP:
  78             opt_help(dsaparam_options);
  79             ret = 0;
  80             goto end;
  81         case OPT_INFORM:
  82             if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &informat))
  83                 goto opthelp;
  84             break;
  85         case OPT_IN:
  86             infile = opt_arg();
  87             break;
  88         case OPT_OUTFORM:
  89             if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &outformat))
  90                 goto opthelp;
  91             break;
  92         case OPT_OUT:
  93             outfile = opt_arg();
  94             break;
  95         case OPT_ENGINE:
  96             e = setup_engine(opt_arg(), 0);
  97             break;
  98         case OPT_TEXT:
  99             text = 1;
 100             break;
 101         case OPT_C:
 102             C = 1;
 103             break;
 104         case OPT_GENKEY:
 105             genkey = 1;
 106             break;
 107         case OPT_R_CASES:
 108             if (!opt_rand(o))
 109                 goto end;
 110             break;
 111         case OPT_NOOUT:
 112             noout = 1;
 113             break;
 114         case OPT_VERBOSE:
 115             verbose = 1;
 116             break;
 117         }
 118     }
 119     argc = opt_num_rest();
 120     argv = opt_rest();
 121
 122     if (argc == 1) {
 123         if (!opt_int(argv[0], &num) || num < 0)
 124             goto end;
 125         /* generate a key */
 126         numbits = num;
 127     }
 128     private = genkey ? 1 : 0;
 129
 130     in = bio_open_default(infile, 'r', informat);
 131     if (in == NULL)
 132         goto end;
 133     out = bio_open_owner(outfile, outformat, private);
 134     if (out == NULL)
 135         goto end;
 136
 137     if (numbits > 0) {
 138         if (numbits > OPENSSL_DSA_MAX_MODULUS_BITS)
 139             BIO_printf(bio_err,
 140                        "Warning: It is not recommended to use more than %d bit for DSA keys.\n"
 141                        "         Your key size is %d! Larger key size may behave not as expected.\n",
 142                        OPENSSL_DSA_MAX_MODULUS_BITS, numbits);
 143
 144         cb = BN_GENCB_new();
 145         if (cb == NULL) {
 146             BIO_printf(bio_err, "Error allocating BN_GENCB object\n");
 147             goto end;
 148         }
 149         BN_GENCB_set(cb, dsa_cb, bio_err);
 150         dsa = DSA_new();
 151         if (dsa == NULL) {
 152             BIO_printf(bio_err, "Error allocating DSA object\n");
 153             goto end;
 154         }
 155         if (verbose) {
 156             BIO_printf(bio_err, "Generating DSA parameters, %d bit long prime\n",
 157                        num);
 158             BIO_printf(bio_err, "This could take some time\n");
 159         }
 160         if (!DSA_generate_parameters_ex(dsa, num, NULL, 0, NULL, NULL, cb)) {
 161             ERR_print_errors(bio_err);
 162             BIO_printf(bio_err, "Error, DSA key generation failed\n");
 163             goto end;
 164         }
 165     } else if (informat == FORMAT_ASN1) {
 166         dsa = d2i_DSAparams_bio(in, NULL);
 167     } else {
 168         dsa = PEM_read_bio_DSAparams(in, NULL, NULL, NULL);
 169     }
 170     if (dsa == NULL) {
 171         BIO_printf(bio_err, "unable to load DSA parameters\n");
 172         ERR_print_errors(bio_err);
 173         goto end;
 174     }
 175
 176     if (text) {
 177         DSAparams_print(out, dsa);
 178     }
 179
 180     if (C) {
 181         const BIGNUM *p = NULL, *q = NULL, *g = NULL;
 182         unsigned char *data;
 183         int len, bits_p;
 184
 185         DSA_get0_pqg(dsa, &p, &q, &g);
 186         len = BN_num_bytes(p);
 187         bits_p = BN_num_bits(p);
 188
 189         data = app_malloc(len + 20, "BN space");
 190
 191         BIO_printf(bio_out, "static DSA *get_dsa%d(void)\n{\n", bits_p);
 192         print_bignum_var(bio_out, p, "dsap", bits_p, data);
 193         print_bignum_var(bio_out, q, "dsaq", bits_p, data);
 194         print_bignum_var(bio_out, g, "dsag", bits_p, data);
 195         BIO_printf(bio_out, "    DSA *dsa = DSA_new();\n"
 196                             "    BIGNUM *p, *q, *g;\n"
 197                             "\n");
 198         BIO_printf(bio_out, "    if (dsa == NULL)\n"
 199                             "        return NULL;\n");
 200         BIO_printf(bio_out, "    if (!DSA_set0_pqg(dsa, p = BN_bin2bn(dsap_%d, sizeof(dsap_%d), NULL),\n",
 201                    bits_p, bits_p);
 202         BIO_printf(bio_out, "                           q = BN_bin2bn(dsaq_%d, sizeof(dsaq_%d), NULL),\n",
 203                    bits_p, bits_p);
 204         BIO_printf(bio_out, "                           g = BN_bin2bn(dsag_%d, sizeof(dsag_%d), NULL))) {\n",
 205                    bits_p, bits_p);
 206         BIO_printf(bio_out, "        DSA_free(dsa);\n"
 207                             "        BN_free(p);\n"
 208                             "        BN_free(q);\n"
 209                             "        BN_free(g);\n"
 210                             "        return NULL;\n"
 211                             "    }\n"
 212                             "    return dsa;\n}\n");
 213         OPENSSL_free(data);
 214     }
 215
 216     if (outformat == FORMAT_ASN1 && genkey)
 217         noout = 1;
 218
 219     if (!noout) {
 220         if (outformat == FORMAT_ASN1)
 221             i = i2d_DSAparams_bio(out, dsa);
 222         else
 223             i = PEM_write_bio_DSAparams(out, dsa);
 224         if (!i) {
 225             BIO_printf(bio_err, "unable to write DSA parameters\n");
 226             ERR_print_errors(bio_err);
 227             goto end;
 228         }
 229     }
 230     if (genkey) {
 231         DSA *dsakey;
 232
 233         if ((dsakey = DSAparams_dup(dsa)) == NULL)
 234             goto end;
 235         if (!DSA_generate_key(dsakey)) {
 236             ERR_print_errors(bio_err);
 237             DSA_free(dsakey);
 238             goto end;
 239         }
 240         assert(private);
 241         if (outformat == FORMAT_ASN1)
 242             i = i2d_DSAPrivateKey_bio(out, dsakey);
 243         else
 244             i = PEM_write_bio_DSAPrivateKey(out, dsakey, NULL, NULL, 0, NULL,
 245                                             NULL);
 246         DSA_free(dsakey);
 247     }
 248     ret = 0;
 249  end:
 250     BN_GENCB_free(cb);
 251     BIO_free(in);
 252     BIO_free_all(out);
 253     DSA_free(dsa);
 254     release_engine(e);
 255     return ret;
 256 }
 257
 258 static int dsa_cb(int p, int n, BN_GENCB *cb)
 259 {
 260     static const char symbols[] = ".+*\n";
 261     char c = (p >= 0 && (size_t)p < sizeof(symbols) - 1) ? symbols[p] : '?';
 262
 263     if (!verbose)
 264         return 1;
 265
 266     BIO_write(BN_GENCB_get_arg(cb), &c, 1);
 267     (void)BIO_flush(BN_GENCB_get_arg(cb));
 268     return 1;
 269 }
 270 #endif