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 verbose = 0;
  34
  35 static int genrsa_cb(int p, int n, BN_GENCB *cb);
  36
  37 typedef enum OPTION_choice {
  38     OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,
  39     OPT_3, OPT_F4, OPT_ENGINE,
  40     OPT_OUT, OPT_PASSOUT, OPT_CIPHER, OPT_PRIMES, OPT_VERBOSE,
  41     OPT_R_ENUM
  42 } OPTION_CHOICE;
  43
  44 const OPTIONS genrsa_options[] = {
  45     {"help", OPT_HELP, '-', "Display this summary"},
  46     {"3", OPT_3, '-', "Use 3 for the E value"},
  47     {"F4", OPT_F4, '-', "Use F4 (0x10001) for the E value"},
  48     {"f4", OPT_F4, '-', "Use F4 (0x10001) for the E value"},
  49     {"out", OPT_OUT, '>', "Output the key to specified file"},
  50     OPT_R_OPTIONS,
  51     {"passout", OPT_PASSOUT, 's', "Output file pass phrase source"},
  52     {"", OPT_CIPHER, '-', "Encrypt the output with any supported cipher"},
  53 # ifndef OPENSSL_NO_ENGINE
  54     {"engine", OPT_ENGINE, 's', "Use engine, possibly a hardware device"},
  55 # endif
  56     {"primes", OPT_PRIMES, 'p', "Specify number of primes"},
  57     {"verbose", OPT_VERBOSE, '-', "Verbose output"},
  58     {NULL}
  59 };
  60
  61 int genrsa_main(int argc, char **argv)
  62 {
  63     BN_GENCB *cb = BN_GENCB_new();
  64     PW_CB_DATA cb_data;
  65     ENGINE *eng = NULL;
  66     BIGNUM *bn = BN_new();
  67     BIO *out = NULL;
  68     const BIGNUM *e;
  69     RSA *rsa = NULL;
  70     const EVP_CIPHER *enc = NULL;
  71     int ret = 1, num = DEFBITS, private = 0, primes = DEFPRIMES;
  72     unsigned long f4 = RSA_F4;
  73     char *outfile = NULL, *passoutarg = NULL, *passout = NULL;
  74     char *prog, *hexe, *dece;
  75     OPTION_CHOICE o;
  76
  77     if (bn == NULL || cb == NULL)
  78         goto end;
  79
  80     BN_GENCB_set(cb, genrsa_cb, bio_err);
  81
  82     prog = opt_init(argc, argv, genrsa_options);
  83     while ((o = opt_next()) != OPT_EOF) {
  84         switch (o) {
  85         case OPT_EOF:
  86         case OPT_ERR:
  87 opthelp:
  88             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
  89             goto end;
  90         case OPT_HELP:
  91             ret = 0;
  92             opt_help(genrsa_options);
  93             goto end;
  94         case OPT_3:
  95             f4 = 3;
  96             break;
  97         case OPT_F4:
  98             f4 = RSA_F4;
  99             break;
 100         case OPT_OUT:
 101             outfile = opt_arg();
 102             break;
 103         case OPT_ENGINE:
 104             eng = setup_engine(opt_arg(), 0);
 105             break;
 106         case OPT_R_CASES:
 107             if (!opt_rand(o))
 108                 goto end;
 109             break;
 110         case OPT_PASSOUT:
 111             passoutarg = opt_arg();
 112             break;
 113         case OPT_CIPHER:
 114             if (!opt_cipher(opt_unknown(), &enc))
 115                 goto end;
 116             break;
 117         case OPT_PRIMES:
 118             if (!opt_int(opt_arg(), &primes))
 119                 goto end;
 120             break;
 121         case OPT_VERBOSE:
 122             verbose = 1;
 123             break;
 124         }
 125     }
 126     argc = opt_num_rest();
 127     argv = opt_rest();
 128
 129     if (argc == 1) {
 130         if (!opt_int(argv[0], &num) || num <= 0)
 131             goto end;
 132         if (num > OPENSSL_RSA_MAX_MODULUS_BITS)
 133             BIO_printf(bio_err,
 134                        "Warning: It is not recommended to use more than %d bit for RSA keys.\n"
 135                        "         Your key size is %d! Larger key size may behave not as expected.\n",
 136                        OPENSSL_RSA_MAX_MODULUS_BITS, num);
 137     } else if (argc > 0) {
 138         BIO_printf(bio_err, "Extra arguments given.\n");
 139         goto opthelp;
 140     }
 141
 142     private = 1;
 143     if (!app_passwd(NULL, passoutarg, NULL, &passout)) {
 144         BIO_printf(bio_err, "Error getting password\n");
 145         goto end;
 146     }
 147
 148     out = bio_open_owner(outfile, FORMAT_PEM, private);
 149     if (out == NULL)
 150         goto end;
 151
 152     if (verbose)
 153         BIO_printf(bio_err, "Generating RSA private key, %d bit long modulus (%d primes)\n",
 154                    num, primes);
 155     rsa = eng ? RSA_new_method(eng) : RSA_new();
 156     if (rsa == NULL)
 157         goto end;
 158
 159     if (!BN_set_word(bn, f4)
 160         || !RSA_generate_multi_prime_key(rsa, num, primes, bn, cb))
 161         goto end;
 162
 163     RSA_get0_key(rsa, NULL, &e, NULL);
 164     hexe = BN_bn2hex(e);
 165     dece = BN_bn2dec(e);
 166     if (hexe && dece && verbose) {
 167         BIO_printf(bio_err, "e is %s (0x%s)\n", dece, hexe);
 168     }
 169     OPENSSL_free(hexe);
 170     OPENSSL_free(dece);
 171     cb_data.password = passout;
 172     cb_data.prompt_info = outfile;
 173     assert(private);
 174     if (!PEM_write_bio_RSAPrivateKey(out, rsa, enc, NULL, 0,
 175                                      (pem_password_cb *)password_callback,
 176                                      &cb_data))
 177         goto end;
 178
 179     ret = 0;
 180  end:
 181     BN_free(bn);
 182     BN_GENCB_free(cb);
 183     RSA_free(rsa);
 184     BIO_free_all(out);
 185     release_engine(eng);
 186     OPENSSL_free(passout);
 187     if (ret != 0)
 188         ERR_print_errors(bio_err);
 189     return ret;
 190 }
 191
 192 static int genrsa_cb(int p, int n, BN_GENCB *cb)
 193 {
 194     char c = '*';
 195
 196     if (!verbose)
 197         return 1;
 198
 199     if (p == 0)
 200         c = '.';
 201     if (p == 1)
 202         c = '+';
 203     if (p == 2)
 204         c = '*';
 205     if (p == 3)
 206         c = '\n';
 207     BIO_write(BN_GENCB_get_arg(cb), &c, 1);
 208     (void)BIO_flush(BN_GENCB_get_arg(cb));
 209     return 1;
 210 }
 211 #endif