apps/genrsa.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_RSA
  12 NON_EMPTY_TRANSLATION_UNIT
  13 #else
  14
  15 # include <stdio.h>
  16 # include <string.h>
  17 # include <sys/types.h>
  18 # include <sys/stat.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/rsa.h>
  25 # include <openssl/evp.h>
  26 # include <openssl/x509.h>
  27 # include <openssl/pem.h>
  28 # include <openssl/rand.h>
  29
  30 # define DEFBITS 2048
  31 # define DEFPRIMES 2
  32
  33 static int genrsa_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_3, OPT_F4, OPT_ENGINE,
  38     OPT_OUT, OPT_PASSOUT, OPT_CIPHER, OPT_PRIMES,
  39     OPT_R_ENUM
  40 } OPTION_CHOICE;
  41
  42 const OPTIONS genrsa_options[] = {
  43     {"help", OPT_HELP, '-', "Display this summary"},
  44     {"3", OPT_3, '-', "Use 3 for the E value"},
  45     {"F4", OPT_F4, '-', "Use F4 (0x10001) for the E value"},
  46     {"f4", OPT_F4, '-', "Use F4 (0x10001) for the E value"},
  47     {"out", OPT_OUT, '>', "Output the key to specified file"},
  48     OPT_R_OPTIONS,
  49     {"passout", OPT_PASSOUT, 's', "Output file pass phrase source"},
  50     {"", OPT_CIPHER, '-', "Encrypt the output with any supported cipher"},
  51 # ifndef OPENSSL_NO_ENGINE
  52     {"engine", OPT_ENGINE, 's', "Use engine, possibly a hardware device"},
  53 # endif
  54     {"primes", OPT_PRIMES, 'p', "Specify number of primes"},
  55     {NULL}
  56 };
  57
  58 int genrsa_main(int argc, char **argv)
  59 {
  60     BN_GENCB *cb = BN_GENCB_new();
  61     PW_CB_DATA cb_data;
  62     ENGINE *eng = NULL;
  63     BIGNUM *bn = BN_new();
  64     BIO *out = NULL;
  65     const BIGNUM *e;
  66     RSA *rsa = NULL;
  67     const EVP_CIPHER *enc = NULL;
  68     int ret = 1, num = DEFBITS, private = 0, primes = DEFPRIMES;
  69     unsigned long f4 = RSA_F4;
  70     char *outfile = NULL, *passoutarg = NULL, *passout = NULL;
  71     char *prog, *hexe, *dece;
  72     OPTION_CHOICE o;
  73
  74     if (bn == NULL || cb == NULL)
  75         goto end;
  76
  77     BN_GENCB_set(cb, genrsa_cb, bio_err);
  78
  79     prog = opt_init(argc, argv, genrsa_options);
  80     while ((o = opt_next()) != OPT_EOF) {
  81         switch (o) {
  82         case OPT_EOF:
  83         case OPT_ERR:
  84 opthelp:
  85             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
  86             goto end;
  87         case OPT_HELP:
  88             ret = 0;
  89             opt_help(genrsa_options);
  90             goto end;
  91         case OPT_3:
  92             f4 = 3;
  93             break;
  94         case OPT_F4:
  95             f4 = RSA_F4;
  96             break;
  97         case OPT_OUT:
  98             outfile = opt_arg();
  99             break;
 100         case OPT_ENGINE:
 101             eng = setup_engine(opt_arg(), 0);
 102             break;
 103         case OPT_R_CASES:
 104             if (!opt_rand(o))
 105                 goto end;
 106             break;
 107         case OPT_PASSOUT:
 108             passoutarg = opt_arg();
 109             break;
 110         case OPT_CIPHER:
 111             if (!opt_cipher(opt_unknown(), &enc))
 112                 goto end;
 113             break;
 114         case OPT_PRIMES:
 115             if (!opt_int(opt_arg(), &primes))
 116                 goto end;
 117             break;
 118         }
 119     }
 120     argc = opt_num_rest();
 121     argv = opt_rest();
 122
 123     if (argc == 1) {
 124         if (!opt_int(argv[0], &num) || num <= 0)
 125             goto end;
 126         if (num > OPENSSL_RSA_MAX_MODULUS_BITS)
 127             BIO_printf(bio_err,
 128                        "Warning: It is not recommended to use more than %d bit for RSA keys.\n"
 129                        "         Your key size is %d! Larger key size may behave not as expected.\n",
 130                        OPENSSL_RSA_MAX_MODULUS_BITS, num);
 131     } else if (argc > 0) {
 132         BIO_printf(bio_err, "Extra arguments given.\n");
 133         goto opthelp;
 134     }
 135
 136     private = 1;
 137     if (!app_passwd(NULL, passoutarg, NULL, &passout)) {
 138         BIO_printf(bio_err, "Error getting password\n");
 139         goto end;
 140     }
 141
 142     out = bio_open_owner(outfile, FORMAT_PEM, private);
 143     if (out == NULL)
 144         goto end;
 145
 146     BIO_printf(bio_err, "Generating RSA private key, %d bit long modulus (%d primes)\n",
 147                num, primes);
 148     rsa = eng ? RSA_new_method(eng) : RSA_new();
 149     if (rsa == NULL)
 150         goto end;
 151
 152     if (!BN_set_word(bn, f4)
 153         || !RSA_generate_multi_prime_key(rsa, num, primes, bn, cb))
 154         goto end;
 155
 156     RSA_get0_key(rsa, NULL, &e, NULL);
 157     hexe = BN_bn2hex(e);
 158     dece = BN_bn2dec(e);
 159     if (hexe && dece) {
 160         BIO_printf(bio_err, "e is %s (0x%s)\n", dece, hexe);
 161     }
 162     OPENSSL_free(hexe);
 163     OPENSSL_free(dece);
 164     cb_data.password = passout;
 165     cb_data.prompt_info = outfile;
 166     assert(private);
 167     if (!PEM_write_bio_RSAPrivateKey(out, rsa, enc, NULL, 0,
 168                                      (pem_password_cb *)password_callback,
 169                                      &cb_data))
 170         goto end;
 171
 172     ret = 0;
 173  end:
 174     BN_free(bn);
 175     BN_GENCB_free(cb);
 176     RSA_free(rsa);
 177     BIO_free_all(out);
 178     release_engine(eng);
 179     OPENSSL_free(passout);
 180     if (ret != 0)
 181         ERR_print_errors(bio_err);
 182     return ret;
 183 }
 184
 185 static int genrsa_cb(int p, int n, BN_GENCB *cb)
 186 {
 187     char c = '*';
 188
 189     if (p == 0)
 190         c = '.';
 191     if (p == 1)
 192         c = '+';
 193     if (p == 2)
 194         c = '*';
 195     if (p == 3)
 196         c = '\n';
 197     BIO_write(BN_GENCB_get_arg(cb), &c, 1);
 198     (void)BIO_flush(BN_GENCB_get_arg(cb));
 199     return 1;
 200 }
 201 #endif