text: /*
   * Copyright 1995-2018 The OpenSSL Project Authors. All Rights Reserved.
   *
   * Licensed under the OpenSSL license (the "License").  You may not use
   * this file except in compliance with the License.  You can obtain a copy
   * in the file LICENSE in the source distribution or at
   * https://www.openssl.org/source/license.html
   */
  
  #include <openssl/opensslconf.h>
  #ifdef OPENSSL_NO_DSA
  NON_EMPTY_TRANSLATION_UNIT
  #else
  
  # include <stdio.h>
  # include <stdlib.h>
  #if 0 /* No time by eunbin */
  # include <time.h>
  #endif
  # include <string.h>
  # include "apps.h"
  # include "progs.h"
  # include <openssl/bio.h>
  # include <openssl/err.h>
  # include <openssl/bn.h>
  # include <openssl/dsa.h>
  # include <openssl/x509.h>
  # include <openssl/pem.h>
  
  static int dsa_cb(int p, int n, BN_GENCB *cb);
  
  typedef enum OPTION_choice {
      OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,
      OPT_INFORM, OPT_OUTFORM, OPT_IN, OPT_OUT, OPT_TEXT, OPT_C,
      OPT_NOOUT, OPT_GENKEY, OPT_ENGINE, OPT_R_ENUM
  } OPTION_CHOICE;
  
  const OPTIONS dsaparam_options[] = {
      {"help", OPT_HELP, '-', "Display this summary"},
      {"inform", OPT_INFORM, 'F', "Input format - DER or PEM"},
      {"in", OPT_IN, '<', "Input file"},
      {"outform", OPT_OUTFORM, 'F', "Output format - DER or PEM"},
      {"out", OPT_OUT, '>', "Output file"},
      {"text", OPT_TEXT, '-', "Print as text"},
      {"C", OPT_C, '-', "Output C code"},
      {"noout", OPT_NOOUT, '-', "No output"},
      {"genkey", OPT_GENKEY, '-', "Generate a DSA key"},
      OPT_R_OPTIONS,
  # ifndef OPENSSL_NO_ENGINE
      {"engine", OPT_ENGINE, 's', "Use engine e, possibly a hardware device"},
  # endif
      {NULL}
  };
  
  int dsaparam_main(int argc, char **argv)
  {
      ENGINE *e = NULL;
      DSA *dsa = NULL;
      BIO *in = NULL, *out = NULL;
      BN_GENCB *cb = NULL;
      int numbits = -1, num = 0, genkey = 0;
      int informat = FORMAT_PEM, outformat = FORMAT_PEM, noout = 0, C = 0;
      int ret = 1, i, text = 0, private = 0;
      char *infile = NULL, *outfile = NULL, *prog;
      OPTION_CHOICE o;
  
      prog = opt_init(argc, argv, dsaparam_options);
      while ((o = opt_next()) != OPT_EOF) {
          switch (o) {
          case OPT_EOF:
          case OPT_ERR:
   opthelp:
              BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
              goto end;
          case OPT_HELP:
              opt_help(dsaparam_options);
              ret = 0;
              goto end;
          case OPT_INFORM:
              if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &informat))
                  goto opthelp;
              break;
          case OPT_IN:
              infile = opt_arg();
              break;
          case OPT_OUTFORM:
              if (!opt_format(opt_arg(), OPT_FMT_PEMDER, &outformat))
                  goto opthelp;
              break;
          case OPT_OUT:
              outfile = opt_arg();
              break;
          case OPT_ENGINE:
              e = setup_engine(opt_arg(), 0);
              break;
          case OPT_TEXT:
              text = 1;
              break;
          case OPT_C:
              C = 1;
              break;
          case OPT_GENKEY:
              genkey = 1;
              break;
          case OPT_R_CASES:
              if (!opt_rand(o))
                  goto end;
              break;
          case OPT_NOOUT:
              noout = 1;
              break;
          }
      }
      argc = opt_num_rest();
      argv = opt_rest();
  
      if (argc == 1) {
          if (!opt_int(argv[0], &num) || num < 0)
              goto end;
          /* generate a key */
          numbits = num;
      }
      private = genkey ? 1 : 0;
  
      in = bio_open_default(infile, 'r', informat);
      if (in == NULL)
          goto end;
      out = bio_open_owner(outfile, outformat, private);
      if (out == NULL)
          goto end;
  
      if (numbits > 0) {
          if (numbits > OPENSSL_DSA_MAX_MODULUS_BITS)
              BIO_printf(bio_err,
                         "Warning: It is not recommended to use more than %d bit for DSA keys.\n"
                         "         Your key size is %d! Larger key size may behave not as expected.\n",
                         OPENSSL_DSA_MAX_MODULUS_BITS, numbits);
  
          cb = BN_GENCB_new();
          if (cb == NULL) {
              BIO_printf(bio_err, "Error allocating BN_GENCB object\n");
              goto end;
          }
          BN_GENCB_set(cb, dsa_cb, bio_err);
          dsa = DSA_new();
          if (dsa == NULL) {
              BIO_printf(bio_err, "Error allocating DSA object\n");
              goto end;
          }
          BIO_printf(bio_err, "Generating DSA parameters, %d bit long prime\n",
                     num);
          BIO_printf(bio_err, "This could take some time\n");
          if (!DSA_generate_parameters_ex(dsa, num, NULL, 0, NULL, NULL, cb)) {
              ERR_print_errors(bio_err);
              BIO_printf(bio_err, "Error, DSA key generation failed\n");
              goto end;
          }
      } else if (informat == FORMAT_ASN1) {
          dsa = d2i_DSAparams_bio(in, NULL);
      } else {
          dsa = PEM_read_bio_DSAparams(in, NULL, NULL, NULL);
      }
      if (dsa == NULL) {
          BIO_printf(bio_err, "unable to load DSA parameters\n");
          ERR_print_errors(bio_err);
          goto end;
      }
  
      if (text) {
          DSAparams_print(out, dsa);
      }
  
      if (C) {
          const BIGNUM *p = NULL, *q = NULL, *g = NULL;
          unsigned char *data;
          int len, bits_p;
  
          DSA_get0_pqg(dsa, &p, &q, &g);
          len = BN_num_bytes(p);
          bits_p = BN_num_bits(p);
  
          data = app_malloc(len + 20, "BN space");
  
          BIO_printf(bio_out, "static DSA *get_dsa%d(void)\n{\n", bits_p);
          print_bignum_var(bio_out, p, "dsap", bits_p, data);
          print_bignum_var(bio_out, q, "dsaq", bits_p, data);
          print_bignum_var(bio_out, g, "dsag", bits_p, data);
          BIO_printf(bio_out, "    DSA *dsa = DSA_new();\n"
                              "    BIGNUM *p, *q, *g;\n"
                              "\n");
          BIO_printf(bio_out, "    if (dsa == NULL)\n"
                              "        return NULL;\n");
          BIO_printf(bio_out, "    if (!DSA_set0_pqg(dsa, p = BN_bin2bn(dsap_%d, sizeof(dsap_%d), NULL),\n",
                     bits_p, bits_p);
          BIO_printf(bio_out, "                           q = BN_bin2bn(dsaq_%d, sizeof(dsaq_%d), NULL),\n",
                     bits_p, bits_p);
          BIO_printf(bio_out, "                           g = BN_bin2bn(dsag_%d, sizeof(dsag_%d), NULL))) {\n",
                     bits_p, bits_p);
          BIO_printf(bio_out, "        DSA_free(dsa);\n"
                              "        BN_free(p);\n"
                              "        BN_free(q);\n"
                              "        BN_free(g);\n"
                              "        return NULL;\n"
                              "    }\n"
                              "    return dsa;\n}\n");
          OPENSSL_free(data);
      }
  
      if (outformat == FORMAT_ASN1 && genkey)
          noout = 1;
  
      if (!noout) {
          if (outformat == FORMAT_ASN1)
              i = i2d_DSAparams_bio(out, dsa);
          else
              i = PEM_write_bio_DSAparams(out, dsa);
          if (!i) {
              BIO_printf(bio_err, "unable to write DSA parameters\n");
              ERR_print_errors(bio_err);
              goto end;
          }
      }
      if (genkey) {
          DSA *dsakey;
  
          if ((dsakey = DSAparams_dup(dsa)) == NULL)
              goto end;
          if (!DSA_generate_key(dsakey)) {
              ERR_print_errors(bio_err);
              DSA_free(dsakey);
              goto end;
          }
          assert(private);
          if (outformat == FORMAT_ASN1)
              i = i2d_DSAPrivateKey_bio(out, dsakey);
          else
              i = PEM_write_bio_DSAPrivateKey(out, dsakey, NULL, NULL, 0, NULL,
                                              NULL);
          DSA_free(dsakey);
      }
      ret = 0;
   end:
      BN_GENCB_free(cb);
      BIO_free(in);
      BIO_free_all(out);
      DSA_free(dsa);
      release_engine(e);
      return ret;
  }
  
  static int dsa_cb(int p, int n, BN_GENCB *cb)
  {
      static const char symbols[] = ".+*\n";
      char c = (p >= 0 && (size_t)p < sizeof(symbols) - 1) ? symbols[p] : '?';
  
      BIO_write(BN_GENCB_get_arg(cb), &c, 1);
      (void)BIO_flush(BN_GENCB_get_arg(cb));
      return 1;
  }
  #endif
  