apps/dhparam.c

   1 /*
   2  * Copyright 1995-2017 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_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 <openssl/bio.h>
  21 # include <openssl/err.h>
  22 # include <openssl/bn.h>
  23 # include <openssl/dh.h>
  24 # include <openssl/x509.h>
  25 # include <openssl/pem.h>
  26
  27 # ifndef OPENSSL_NO_DSA
  28 #  include <openssl/dsa.h>
  29 # endif
  30
  31 # define DEFBITS 2048
  32
  33 static int dh_cb(int p, int n, BN_GENCB *cb);
  34
  35 typedef enum OPTION_choice {
  36     OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,
  37     OPT_INFORM, OPT_OUTFORM, OPT_IN, OPT_OUT,
  38     OPT_ENGINE, OPT_CHECK, OPT_TEXT, OPT_NOOUT,
  39     OPT_RAND, OPT_DSAPARAM, OPT_C, OPT_2, OPT_5
  40 } OPTION_CHOICE;
  41
  42 const OPTIONS dhparam_options[] = {
  43     {OPT_HELP_STR, 1, '-', "Usage: %s [flags] [numbits]\n"},
  44     {OPT_HELP_STR, 1, '-', "Valid options are:\n"},
  45     {"help", OPT_HELP, '-', "Display this summary"},
  46     {"in", OPT_IN, '<', "Input file"},
  47     {"inform", OPT_INFORM, 'F', "Input format, DER or PEM"},
  48     {"outform", OPT_OUTFORM, 'F', "Output format, DER or PEM"},
  49     {"out", OPT_OUT, '>', "Output file"},
  50     {"check", OPT_CHECK, '-', "Check the DH parameters"},
  51     {"text", OPT_TEXT, '-', "Print a text form of the DH parameters"},
  52     {"noout", OPT_NOOUT, '-', "Don't output any DH parameters"},
  53     {"rand", OPT_RAND, 's',
  54      "Load the file(s) into the random number generator"},
  55     {"C", OPT_C, '-', "Print C code"},
  56     {"2", OPT_2, '-', "Generate parameters using 2 as the generator value"},
  57     {"5", OPT_5, '-', "Generate parameters using 5 as the generator value"},
  58 # ifndef OPENSSL_NO_DSA
  59     {"dsaparam", OPT_DSAPARAM, '-',
  60      "Read or generate DSA parameters, convert to DH"},
  61 # endif
  62 # ifndef OPENSSL_NO_ENGINE
  63     {"engine", OPT_ENGINE, 's', "Use engine e, possibly a hardware device"},
  64 # endif
  65     {NULL}
  66 };
  67
  68 int dhparam_main(int argc, char **argv)
  69 {
  70     BIO *in = NULL, *out = NULL;
  71     DH *dh = NULL;
  72     char *infile = NULL, *outfile = NULL, *prog, *inrand = NULL;
  73     ENGINE *e = NULL;
  74 #ifndef OPENSSL_NO_DSA
  75     int dsaparam = 0;
  76 #endif
  77     int i, text = 0, C = 0, ret = 1, num = 0, g = 0;
  78     int informat = FORMAT_PEM, outformat = FORMAT_PEM, check = 0, noout = 0;
  79     OPTION_CHOICE o;
  80
  81     prog = opt_init(argc, argv, dhparam_options);
  82     while ((o = opt_next()) != OPT_EOF) {
  83         switch (o) {
  84         case OPT_EOF:
  85         case OPT_ERR:
  86  opthelp:
  87             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
  88             goto end;
  89         case OPT_HELP:
  90             opt_help(dhparam_options);
  91             ret = 0;
  92             goto end;
  93         case OPT_INFORM:
  94             if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &informat))
  95                 goto opthelp;
  96             break;
  97         case OPT_OUTFORM:
  98             if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &outformat))
  99                 goto opthelp;
 100             break;
 101         case OPT_IN:
 102             infile = opt_arg();
 103             break;
 104         case OPT_OUT:
 105             outfile = opt_arg();
 106             break;
 107         case OPT_ENGINE:
 108             e = setup_engine(opt_arg(), 0);
 109             break;
 110         case OPT_CHECK:
 111             check = 1;
 112             break;
 113         case OPT_TEXT:
 114             text = 1;
 115             break;
 116         case OPT_DSAPARAM:
 117 #ifndef OPENSSL_NO_DSA
 118             dsaparam = 1;
 119 #endif
 120             break;
 121         case OPT_C:
 122             C = 1;
 123             break;
 124         case OPT_2:
 125             g = 2;
 126             break;
 127         case OPT_5:
 128             g = 5;
 129             break;
 130         case OPT_NOOUT:
 131             noout = 1;
 132             break;
 133         case OPT_RAND:
 134             inrand = opt_arg();
 135             break;
 136         }
 137     }
 138     argc = opt_num_rest();
 139     argv = opt_rest();
 140
 141     if (argv[0] != NULL && (!opt_int(argv[0], &num) || num <= 0))
 142         goto end;
 143
 144     if (g && !num)
 145         num = DEFBITS;
 146
 147 # ifndef OPENSSL_NO_DSA
 148     if (dsaparam && g) {
 149         BIO_printf(bio_err,
 150                    "generator may not be chosen for DSA parameters\n");
 151         goto end;
 152     }
 153 # endif
 154     /* DH parameters */
 155     if (num && !g)
 156         g = 2;
 157
 158     if (num) {
 159
 160         BN_GENCB *cb;
 161         cb = BN_GENCB_new();
 162         if (cb == NULL) {
 163             ERR_print_errors(bio_err);
 164             goto end;
 165         }
 166
 167         BN_GENCB_set(cb, dh_cb, bio_err);
 168         if (!app_RAND_load_file(NULL, 1) && inrand == NULL) {
 169             BIO_printf(bio_err,
 170                        "warning, not much extra random data, consider using the -rand option\n");
 171         }
 172         if (inrand != NULL)
 173             BIO_printf(bio_err, "%ld semi-random bytes loaded\n",
 174                        app_RAND_load_files(inrand));
 175
 176 # ifndef OPENSSL_NO_DSA
 177         if (dsaparam) {
 178             DSA *dsa = DSA_new();
 179
 180             BIO_printf(bio_err,
 181                        "Generating DSA parameters, %d bit long prime\n", num);
 182             if (dsa == NULL
 183                 || !DSA_generate_parameters_ex(dsa, num, NULL, 0, NULL, NULL,
 184                                                cb)) {
 185                 DSA_free(dsa);
 186                 BN_GENCB_free(cb);
 187                 ERR_print_errors(bio_err);
 188                 goto end;
 189             }
 190
 191             dh = DSA_dup_DH(dsa);
 192             DSA_free(dsa);
 193             if (dh == NULL) {
 194                 BN_GENCB_free(cb);
 195                 ERR_print_errors(bio_err);
 196                 goto end;
 197             }
 198         } else
 199 # endif
 200         {
 201             dh = DH_new();
 202             BIO_printf(bio_err,
 203                        "Generating DH parameters, %d bit long safe prime, generator %d\n",
 204                        num, g);
 205             BIO_printf(bio_err, "This is going to take a long time\n");
 206             if (dh == NULL || !DH_generate_parameters_ex(dh, num, g, cb)) {
 207                 BN_GENCB_free(cb);
 208                 ERR_print_errors(bio_err);
 209                 goto end;
 210             }
 211         }
 212
 213         BN_GENCB_free(cb);
 214         app_RAND_write_file(NULL);
 215     } else {
 216
 217         in = bio_open_default(infile, 'r', informat);
 218         if (in == NULL)
 219             goto end;
 220
 221 # ifndef OPENSSL_NO_DSA
 222         if (dsaparam) {
 223             DSA *dsa;
 224
 225             if (informat == FORMAT_ASN1)
 226                 dsa = d2i_DSAparams_bio(in, NULL);
 227             else                /* informat == FORMAT_PEM */
 228                 dsa = PEM_read_bio_DSAparams(in, NULL, NULL, NULL);
 229
 230             if (dsa == NULL) {
 231                 BIO_printf(bio_err, "unable to load DSA parameters\n");
 232                 ERR_print_errors(bio_err);
 233                 goto end;
 234             }
 235
 236             dh = DSA_dup_DH(dsa);
 237             DSA_free(dsa);
 238             if (dh == NULL) {
 239                 ERR_print_errors(bio_err);
 240                 goto end;
 241             }
 242         } else
 243 # endif
 244         {
 245             if (informat == FORMAT_ASN1) {
 246                 /*
 247                  * We have no PEM header to determine what type of DH params it
 248                  * is. We'll just try both.
 249                  */
 250                 dh = d2i_DHparams_bio(in, NULL);
 251                 /* BIO_reset() returns 0 for success for file BIOs only!!! */
 252                 if (dh == NULL && BIO_reset(in) == 0)
 253                     dh = d2i_DHxparams_bio(in, NULL);
 254             } else {
 255                 /* informat == FORMAT_PEM */
 256                 dh = PEM_read_bio_DHparams(in, NULL, NULL, NULL);
 257             }
 258
 259             if (dh == NULL) {
 260                 BIO_printf(bio_err, "unable to load DH parameters\n");
 261                 ERR_print_errors(bio_err);
 262                 goto end;
 263             }
 264         }
 265
 266         /* dh != NULL */
 267     }
 268
 269     out = bio_open_default(outfile, 'w', outformat);
 270     if (out == NULL)
 271         goto end;
 272
 273     if (text) {
 274         DHparams_print(out, dh);
 275     }
 276
 277     if (check) {
 278         if (!DH_check(dh, &i)) {
 279             ERR_print_errors(bio_err);
 280             goto end;
 281         }
 282         if (i & DH_CHECK_P_NOT_PRIME)
 283             BIO_printf(bio_err, "WARNING: p value is not prime\n");
 284         if (i & DH_CHECK_P_NOT_SAFE_PRIME)
 285             BIO_printf(bio_err, "WARNING: p value is not a safe prime\n");
 286         if (i & DH_CHECK_Q_NOT_PRIME)
 287             BIO_printf(bio_err, "WARNING: q value is not a prime\n");
 288         if (i & DH_CHECK_INVALID_Q_VALUE)
 289             BIO_printf(bio_err, "WARNING: q value is invalid\n");
 290         if (i & DH_CHECK_INVALID_J_VALUE)
 291             BIO_printf(bio_err, "WARNING: j value is invalid\n");
 292         if (i & DH_UNABLE_TO_CHECK_GENERATOR)
 293             BIO_printf(bio_err,
 294                        "WARNING: unable to check the generator value\n");
 295         if (i & DH_NOT_SUITABLE_GENERATOR)
 296             BIO_printf(bio_err, "WARNING: the g value is not a generator\n");
 297         if (i == 0)
 298             BIO_printf(bio_err, "DH parameters appear to be ok.\n");
 299         if (num != 0 && i != 0) {
 300             /*
 301              * We have generated parameters but DH_check() indicates they are
 302              * invalid! This should never happen!
 303              */
 304             BIO_printf(bio_err, "ERROR: Invalid parameters generated\n");
 305             goto end;
 306         }
 307     }
 308     if (C) {
 309         unsigned char *data;
 310         int len, bits;
 311         const BIGNUM *pbn, *gbn;
 312
 313         len = DH_size(dh);
 314         bits = DH_bits(dh);
 315         DH_get0_pqg(dh, &pbn, NULL, &gbn);
 316         data = app_malloc(len, "print a BN");
 317         BIO_printf(out, "#ifndef HEADER_DH_H\n"
 318                         "# include <openssl/dh.h>\n"
 319                         "#endif\n"
 320                         "\n");
 321         BIO_printf(out, "DH *get_dh%d()\n{\n", bits);
 322         print_bignum_var(out, pbn, "dhp", bits, data);
 323         print_bignum_var(out, gbn, "dhg", bits, data);
 324         BIO_printf(out, "    DH *dh = DH_new();\n"
 325                         "    BIGNUM *dhp_bn, *dhg_bn;\n"
 326                         "\n"
 327                         "    if (dh == NULL)\n"
 328                         "        return NULL;\n");
 329         BIO_printf(out, "    dhp_bn = BN_bin2bn(dhp_%d, sizeof (dhp_%d), NULL);\n",
 330                    bits, bits);
 331         BIO_printf(out, "    dhg_bn = BN_bin2bn(dhg_%d, sizeof (dhg_%d), NULL);\n",
 332                    bits, bits);
 333         BIO_printf(out, "    if (dhp_bn == NULL || dhg_bn == NULL\n"
 334                         "            || !DH_set0_pqg(dh, dhp_bn, NULL, dhg_bn)) {\n"
 335                         "        DH_free(dh);\n"
 336                         "        BN_free(dhp_bn);\n"
 337                         "        BN_free(dhg_bn);\n"
 338                         "        return NULL;\n"
 339                         "    }\n");
 340         if (DH_get_length(dh) > 0)
 341             BIO_printf(out,
 342                         "    if (!DH_set_length(dh, %ld)) {\n"
 343                         "        DH_free(dh);\n"
 344                         "    }\n", DH_get_length(dh));
 345         BIO_printf(out, "    return dh;\n}\n");
 346         OPENSSL_free(data);
 347     }
 348
 349     if (!noout) {
 350         const BIGNUM *q;
 351         DH_get0_pqg(dh, NULL, &q, NULL);
 352         if (outformat == FORMAT_ASN1) {
 353             if (q != NULL)
 354                 i = i2d_DHxparams_bio(out, dh);
 355             else
 356                 i = i2d_DHparams_bio(out, dh);
 357         } else if (q != NULL) {
 358             i = PEM_write_bio_DHxparams(out, dh);
 359         } else {
 360             i = PEM_write_bio_DHparams(out, dh);
 361         }
 362         if (!i) {
 363             BIO_printf(bio_err, "unable to write DH parameters\n");
 364             ERR_print_errors(bio_err);
 365             goto end;
 366         }
 367     }
 368     ret = 0;
 369  end:
 370     BIO_free(in);
 371     BIO_free_all(out);
 372     DH_free(dh);
 373     release_engine(e);
 374     return (ret);
 375 }
 376
 377 static int dh_cb(int p, int n, BN_GENCB *cb)
 378 {
 379     char c = '*';
 380
 381     if (p == 0)
 382         c = '.';
 383     if (p == 1)
 384         c = '+';
 385     if (p == 2)
 386         c = '*';
 387     if (p == 3)
 388         c = '\n';
 389     BIO_write(BN_GENCB_get_arg(cb), &c, 1);
 390     (void)BIO_flush(BN_GENCB_get_arg(cb));
 391     return 1;
 392 }
 393 #endif