apps/dhparam.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_DH
  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/dh.h>
  25 # include <openssl/x509.h>
  26 # include <openssl/pem.h>
  27
  28 # ifndef OPENSSL_NO_DSA
  29 #  include <openssl/dsa.h>
  30 # endif
  31
  32 # define DEFBITS 2048
  33
  34 static int dh_cb(int p, int n, BN_GENCB *cb);
  35
  36 typedef enum OPTION_choice {
  37     OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,
  38     OPT_INFORM, OPT_OUTFORM, OPT_IN, OPT_OUT,
  39     OPT_ENGINE, OPT_CHECK, OPT_TEXT, OPT_NOOUT,
  40     OPT_DSAPARAM, OPT_C, OPT_2, OPT_3, OPT_5,
  41     OPT_R_ENUM
  42 } OPTION_CHOICE;
  43
  44 const OPTIONS dhparam_options[] = {
  45     {OPT_HELP_STR, 1, '-', "Usage: %s [options] [numbits]\n"},
  46
  47     OPT_SECTION("General"),
  48     {"help", OPT_HELP, '-', "Display this summary"},
  49     {"check", OPT_CHECK, '-', "Check the DH parameters"},
  50 # ifndef OPENSSL_NO_DSA
  51     {"dsaparam", OPT_DSAPARAM, '-',
  52      "Read or generate DSA parameters, convert to DH"},
  53 # endif
  54 # ifndef OPENSSL_NO_ENGINE
  55     {"engine", OPT_ENGINE, 's', "Use engine e, possibly a hardware device"},
  56 # endif
  57
  58     OPT_SECTION("Input"),
  59     {"in", OPT_IN, '<', "Input file"},
  60     {"inform", OPT_INFORM, 'F', "Input format, DER or PEM"},
  61
  62     OPT_SECTION("Output"),
  63     {"out", OPT_OUT, '>', "Output file"},
  64     {"outform", OPT_OUTFORM, 'F', "Output format, DER or PEM"},
  65     {"text", OPT_TEXT, '-', "Print a text form of the DH parameters"},
  66     {"noout", OPT_NOOUT, '-', "Don't output any DH parameters"},
  67     {"C", OPT_C, '-', "Print C code"},
  68     {"2", OPT_2, '-', "Generate parameters using 2 as the generator value"},
  69     {"3", OPT_3, '-', "Generate parameters using 3 as the generator value"},
  70     {"5", OPT_5, '-', "Generate parameters using 5 as the generator value"},
  71
  72     OPT_R_OPTIONS,
  73
  74     OPT_PARAMETERS(),
  75     {"numbits", 0, 0, "Number of bits if generating parameters (optional)"},
  76     {NULL}
  77 };
  78
  79 int dhparam_main(int argc, char **argv)
  80 {
  81     BIO *in = NULL, *out = NULL;
  82     DH *dh = NULL;
  83     char *infile = NULL, *outfile = NULL, *prog;
  84     ENGINE *e = NULL;
  85 #ifndef OPENSSL_NO_DSA
  86     int dsaparam = 0;
  87 #endif
  88     int i, text = 0, C = 0, ret = 1, num = 0, g = 0;
  89     int informat = FORMAT_PEM, outformat = FORMAT_PEM, check = 0, noout = 0;
  90     OPTION_CHOICE o;
  91
  92     prog = opt_init(argc, argv, dhparam_options);
  93     while ((o = opt_next()) != OPT_EOF) {
  94         switch (o) {
  95         case OPT_EOF:
  96         case OPT_ERR:
  97  opthelp:
  98             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
  99             goto end;
 100         case OPT_HELP:
 101             opt_help(dhparam_options);
 102             ret = 0;
 103             goto end;
 104         case OPT_INFORM:
 105             if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &informat))
 106                 goto opthelp;
 107             break;
 108         case OPT_OUTFORM:
 109             if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &outformat))
 110                 goto opthelp;
 111             break;
 112         case OPT_IN:
 113             infile = opt_arg();
 114             break;
 115         case OPT_OUT:
 116             outfile = opt_arg();
 117             break;
 118         case OPT_ENGINE:
 119             e = setup_engine(opt_arg(), 0);
 120             break;
 121         case OPT_CHECK:
 122             check = 1;
 123             break;
 124         case OPT_TEXT:
 125             text = 1;
 126             break;
 127         case OPT_DSAPARAM:
 128 #ifndef OPENSSL_NO_DSA
 129             dsaparam = 1;
 130 #endif
 131             break;
 132         case OPT_C:
 133             C = 1;
 134             break;
 135         case OPT_2:
 136             g = 2;
 137             break;
 138         case OPT_3:
 139             g = 3;
 140             break;
 141         case OPT_5:
 142             g = 5;
 143             break;
 144         case OPT_NOOUT:
 145             noout = 1;
 146             break;
 147         case OPT_R_CASES:
 148             if (!opt_rand(o))
 149                 goto end;
 150             break;
 151         }
 152     }
 153     argc = opt_num_rest();
 154     argv = opt_rest();
 155
 156     if (argv[0] != NULL && (!opt_int(argv[0], &num) || num <= 0))
 157         goto end;
 158
 159     if (g && !num)
 160         num = DEFBITS;
 161
 162 # ifndef OPENSSL_NO_DSA
 163     if (dsaparam && g) {
 164         BIO_printf(bio_err,
 165                    "generator may not be chosen for DSA parameters\n");
 166         goto end;
 167     }
 168 # endif
 169
 170     out = bio_open_default(outfile, 'w', outformat);
 171     if (out == NULL)
 172         goto end;
 173
 174     /* DH parameters */
 175     if (num && !g)
 176         g = 2;
 177
 178     if (num) {
 179
 180         BN_GENCB *cb;
 181         cb = BN_GENCB_new();
 182         if (cb == NULL) {
 183             ERR_print_errors(bio_err);
 184             goto end;
 185         }
 186
 187         BN_GENCB_set(cb, dh_cb, bio_err);
 188
 189 # ifndef OPENSSL_NO_DSA
 190         if (dsaparam) {
 191             DSA *dsa = DSA_new();
 192
 193             BIO_printf(bio_err,
 194                        "Generating DSA parameters, %d bit long prime\n", num);
 195             if (dsa == NULL
 196                 || !DSA_generate_parameters_ex(dsa, num, NULL, 0, NULL, NULL,
 197                                                cb)) {
 198                 DSA_free(dsa);
 199                 BN_GENCB_free(cb);
 200                 ERR_print_errors(bio_err);
 201                 goto end;
 202             }
 203
 204             dh = DSA_dup_DH(dsa);
 205             DSA_free(dsa);
 206             if (dh == NULL) {
 207                 BN_GENCB_free(cb);
 208                 ERR_print_errors(bio_err);
 209                 goto end;
 210             }
 211         } else
 212 # endif
 213         {
 214             dh = DH_new();
 215             BIO_printf(bio_err,
 216                        "Generating DH parameters, %d bit long safe prime, generator %d\n",
 217                        num, g);
 218             BIO_printf(bio_err, "This is going to take a long time\n");
 219             if (dh == NULL || !DH_generate_parameters_ex(dh, num, g, cb)) {
 220                 BN_GENCB_free(cb);
 221                 ERR_print_errors(bio_err);
 222                 goto end;
 223             }
 224         }
 225
 226         BN_GENCB_free(cb);
 227     } else {
 228
 229         in = bio_open_default(infile, 'r', informat);
 230         if (in == NULL)
 231             goto end;
 232
 233 # ifndef OPENSSL_NO_DSA
 234         if (dsaparam) {
 235             DSA *dsa;
 236
 237             if (informat == FORMAT_ASN1)
 238                 dsa = d2i_DSAparams_bio(in, NULL);
 239             else                /* informat == FORMAT_PEM */
 240                 dsa = PEM_read_bio_DSAparams(in, NULL, NULL, NULL);
 241
 242             if (dsa == NULL) {
 243                 BIO_printf(bio_err, "unable to load DSA parameters\n");
 244                 ERR_print_errors(bio_err);
 245                 goto end;
 246             }
 247
 248             dh = DSA_dup_DH(dsa);
 249             DSA_free(dsa);
 250             if (dh == NULL) {
 251                 ERR_print_errors(bio_err);
 252                 goto end;
 253             }
 254         } else
 255 # endif
 256         {
 257             if (informat == FORMAT_ASN1) {
 258                 /*
 259                  * We have no PEM header to determine what type of DH params it
 260                  * is. We'll just try both.
 261                  */
 262                 dh = d2i_DHparams_bio(in, NULL);
 263                 /* BIO_reset() returns 0 for success for file BIOs only!!! */
 264                 if (dh == NULL && BIO_reset(in) == 0)
 265                     dh = d2i_DHxparams_bio(in, NULL);
 266             } else {
 267                 /* informat == FORMAT_PEM */
 268                 dh = PEM_read_bio_DHparams(in, NULL, NULL, NULL);
 269             }
 270
 271             if (dh == NULL) {
 272                 BIO_printf(bio_err, "unable to load DH parameters\n");
 273                 ERR_print_errors(bio_err);
 274                 goto end;
 275             }
 276         }
 277
 278         /* dh != NULL */
 279     }
 280
 281     if (text) {
 282         DHparams_print(out, dh);
 283     }
 284
 285     if (check) {
 286         if (!DH_check(dh, &i)) {
 287             ERR_print_errors(bio_err);
 288             goto end;
 289         }
 290         if (i & DH_CHECK_P_NOT_PRIME)
 291             BIO_printf(bio_err, "WARNING: p value is not prime\n");
 292         if (i & DH_CHECK_P_NOT_SAFE_PRIME)
 293             BIO_printf(bio_err, "WARNING: p value is not a safe prime\n");
 294         if (i & DH_CHECK_Q_NOT_PRIME)
 295             BIO_printf(bio_err, "WARNING: q value is not a prime\n");
 296         if (i & DH_CHECK_INVALID_Q_VALUE)
 297             BIO_printf(bio_err, "WARNING: q value is invalid\n");
 298         if (i & DH_CHECK_INVALID_J_VALUE)
 299             BIO_printf(bio_err, "WARNING: j value is invalid\n");
 300         if (i & DH_UNABLE_TO_CHECK_GENERATOR)
 301             BIO_printf(bio_err,
 302                        "WARNING: unable to check the generator value\n");
 303         if (i & DH_NOT_SUITABLE_GENERATOR)
 304             BIO_printf(bio_err, "WARNING: the g value is not a generator\n");
 305         if (i == 0)
 306             BIO_printf(bio_err, "DH parameters appear to be ok.\n");
 307         if (num != 0 && i != 0) {
 308             /*
 309              * We have generated parameters but DH_check() indicates they are
 310              * invalid! This should never happen!
 311              */
 312             BIO_printf(bio_err, "ERROR: Invalid parameters generated\n");
 313             goto end;
 314         }
 315     }
 316     if (C) {
 317         unsigned char *data;
 318         int len, bits;
 319         const BIGNUM *pbn, *gbn;
 320
 321         len = DH_size(dh);
 322         bits = DH_bits(dh);
 323         DH_get0_pqg(dh, &pbn, NULL, &gbn);
 324         data = app_malloc(len, "print a BN");
 325
 326         BIO_printf(out, "static DH *get_dh%d(void)\n{\n", bits);
 327         print_bignum_var(out, pbn, "dhp", bits, data);
 328         print_bignum_var(out, gbn, "dhg", bits, data);
 329         BIO_printf(out, "    DH *dh = DH_new();\n"
 330                         "    BIGNUM *p, *g;\n"
 331                         "\n"
 332                         "    if (dh == NULL)\n"
 333                         "        return NULL;\n");
 334         BIO_printf(out, "    p = BN_bin2bn(dhp_%d, sizeof(dhp_%d), NULL);\n",
 335                    bits, bits);
 336         BIO_printf(out, "    g = BN_bin2bn(dhg_%d, sizeof(dhg_%d), NULL);\n",
 337                    bits, bits);
 338         BIO_printf(out, "    if (p == NULL || g == NULL\n"
 339                         "            || !DH_set0_pqg(dh, p, NULL, g)) {\n"
 340                         "        DH_free(dh);\n"
 341                         "        BN_free(p);\n"
 342                         "        BN_free(g);\n"
 343                         "        return NULL;\n"
 344                         "    }\n");
 345         if (DH_get_length(dh) > 0)
 346             BIO_printf(out,
 347                         "    if (!DH_set_length(dh, %ld)) {\n"
 348                         "        DH_free(dh);\n"
 349                         "        return NULL;\n"
 350                         "    }\n", DH_get_length(dh));
 351         BIO_printf(out, "    return dh;\n}\n");
 352         OPENSSL_free(data);
 353     }
 354
 355     if (!noout) {
 356         const BIGNUM *q;
 357         DH_get0_pqg(dh, NULL, &q, NULL);
 358         if (outformat == FORMAT_ASN1) {
 359             if (q != NULL)
 360                 i = i2d_DHxparams_bio(out, dh);
 361             else
 362                 i = i2d_DHparams_bio(out, dh);
 363         } else if (q != NULL) {
 364             i = PEM_write_bio_DHxparams(out, dh);
 365         } else {
 366             i = PEM_write_bio_DHparams(out, dh);
 367         }
 368         if (!i) {
 369             BIO_printf(bio_err, "unable to write DH parameters\n");
 370             ERR_print_errors(bio_err);
 371             goto end;
 372         }
 373     }
 374     ret = 0;
 375  end:
 376     BIO_free(in);
 377     BIO_free_all(out);
 378     DH_free(dh);
 379     release_engine(e);
 380     return ret;
 381 }
 382
 383 static int dh_cb(int p, int n, BN_GENCB *cb)
 384 {
 385     static const char symbols[] = ".+*\n";
 386     char c = (p >= 0 && (size_t)p < sizeof(symbols) - 1) ? symbols[p] : '?';
 387
 388     BIO_write(BN_GENCB_get_arg(cb), &c, 1);
 389     (void)BIO_flush(BN_GENCB_get_arg(cb));
 390     return 1;
 391 }
 392 #endif