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
  12 #include <stdio.h>
  13 #include <string.h>
  14 #include <sys/types.h>
  15 #include <sys/stat.h>
  16 #include "apps.h"
  17 #include "progs.h"
  18 #include <openssl/bio.h>
  19 #include <openssl/err.h>
  20 #include <openssl/bn.h>
  21 #include <openssl/rsa.h>
  22 #include <openssl/evp.h>
  23 #include <openssl/x509.h>
  24 #include <openssl/pem.h>
  25 #include <openssl/rand.h>
  26
  27 #define DEFBITS 2048
  28 #define DEFPRIMES 2
  29
  30 static int verbose = 0;
  31
  32 static int genrsa_cb(EVP_PKEY_CTX *ctx);
  33
  34 typedef enum OPTION_choice {
  35     OPT_ERR = -1, OPT_EOF = 0, OPT_HELP,
  36     OPT_3, OPT_F4, OPT_ENGINE,
  37     OPT_OUT, OPT_PASSOUT, OPT_CIPHER, OPT_PRIMES, OPT_VERBOSE,
  38     OPT_R_ENUM, OPT_PROV_ENUM
  39 } OPTION_CHOICE;
  40
  41 const OPTIONS genrsa_options[] = {
  42     {OPT_HELP_STR, 1, '-', "Usage: %s [options] numbits\n"},
  43
  44     OPT_SECTION("General"),
  45     {"help", OPT_HELP, '-', "Display this summary"},
  46 #ifndef OPENSSL_NO_ENGINE
  47     {"engine", OPT_ENGINE, 's', "Use engine, possibly a hardware device"},
  48 #endif
  49
  50     OPT_SECTION("Input"),
  51     {"3", OPT_3, '-', "Use 3 for the E value"},
  52     {"F4", OPT_F4, '-', "Use F4 (0x10001) for the E value"},
  53     {"f4", OPT_F4, '-', "Use F4 (0x10001) for the E value"},
  54
  55     OPT_SECTION("Output"),
  56     {"out", OPT_OUT, '>', "Output the key to specified file"},
  57     {"passout", OPT_PASSOUT, 's', "Output file pass phrase source"},
  58     {"primes", OPT_PRIMES, 'p', "Specify number of primes"},
  59     {"verbose", OPT_VERBOSE, '-', "Verbose output"},
  60     {"", OPT_CIPHER, '-', "Encrypt the output with any supported cipher"},
  61
  62     OPT_R_OPTIONS,
  63     OPT_PROV_OPTIONS,
  64
  65     OPT_PARAMETERS(),
  66     {"numbits", 0, 0, "Size of key in bits"},
  67     {NULL}
  68 };
  69
  70 int genrsa_main(int argc, char **argv)
  71 {
  72     BN_GENCB *cb = BN_GENCB_new();
  73     ENGINE *eng = NULL;
  74     BIGNUM *bn = BN_new();
  75     RSA *rsa;
  76     BIO *out = NULL;
  77     const BIGNUM *e;
  78     EVP_PKEY *pkey = NULL;
  79     EVP_PKEY_CTX *ctx = NULL;
  80     const EVP_CIPHER *enc = NULL;
  81     int ret = 1, num = DEFBITS, private = 0, primes = DEFPRIMES;
  82     unsigned long f4 = RSA_F4;
  83     char *outfile = NULL, *passoutarg = NULL, *passout = NULL;
  84     char *prog, *hexe, *dece;
  85     OPTION_CHOICE o;
  86     unsigned char *ebuf = NULL;
  87
  88     if (bn == NULL || cb == NULL)
  89         goto end;
  90
  91     prog = opt_init(argc, argv, genrsa_options);
  92     while ((o = opt_next()) != OPT_EOF) {
  93         switch (o) {
  94         case OPT_EOF:
  95         case OPT_ERR:
  96 opthelp:
  97             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
  98             goto end;
  99         case OPT_HELP:
 100             ret = 0;
 101             opt_help(genrsa_options);
 102             goto end;
 103         case OPT_3:
 104             f4 = RSA_3;
 105             break;
 106         case OPT_F4:
 107             f4 = RSA_F4;
 108             break;
 109         case OPT_OUT:
 110             outfile = opt_arg();
 111             break;
 112         case OPT_ENGINE:
 113             eng = setup_engine(opt_arg(), 0);
 114             break;
 115         case OPT_R_CASES:
 116             if (!opt_rand(o))
 117                 goto end;
 118             break;
 119         case OPT_PROV_CASES:
 120             if (!opt_provider(o))
 121                 goto end;
 122             break;
 123         case OPT_PASSOUT:
 124             passoutarg = opt_arg();
 125             break;
 126         case OPT_CIPHER:
 127             if (!opt_cipher(opt_unknown(), &enc))
 128                 goto end;
 129             break;
 130         case OPT_PRIMES:
 131             if (!opt_int(opt_arg(), &primes))
 132                 goto end;
 133             break;
 134         case OPT_VERBOSE:
 135             verbose = 1;
 136             break;
 137         }
 138     }
 139     argc = opt_num_rest();
 140     argv = opt_rest();
 141
 142     if (argc == 1) {
 143         if (!opt_int(argv[0], &num) || num <= 0)
 144             goto end;
 145         if (num > OPENSSL_RSA_MAX_MODULUS_BITS)
 146             BIO_printf(bio_err,
 147                        "Warning: It is not recommended to use more than %d bit for RSA keys.\n"
 148                        "         Your key size is %d! Larger key size may behave not as expected.\n",
 149                        OPENSSL_RSA_MAX_MODULUS_BITS, num);
 150     } else if (argc > 0) {
 151         BIO_printf(bio_err, "Extra arguments given.\n");
 152         goto opthelp;
 153     }
 154
 155     private = 1;
 156     if (!app_passwd(NULL, passoutarg, NULL, &passout)) {
 157         BIO_printf(bio_err, "Error getting password\n");
 158         goto end;
 159     }
 160
 161     out = bio_open_owner(outfile, FORMAT_PEM, private);
 162     if (out == NULL)
 163         goto end;
 164
 165     if (!init_gen_str(&ctx, "RSA", eng, 0))
 166         goto end;
 167
 168     EVP_PKEY_CTX_set_cb(ctx, genrsa_cb);
 169     EVP_PKEY_CTX_set_app_data(ctx, bio_err);
 170
 171     if (EVP_PKEY_CTX_set_rsa_keygen_bits(ctx, num) <= 0) {
 172         BIO_printf(bio_err, "Error setting RSA length\n");
 173         goto end;
 174     }
 175     if (!BN_set_word(bn, f4)) {
 176         BIO_printf(bio_err, "Error allocating RSA public exponent\n");
 177         goto end;
 178     }
 179     if (EVP_PKEY_CTX_set_rsa_keygen_pubexp(ctx, bn) <= 0) {
 180         BIO_printf(bio_err, "Error setting RSA public exponent\n");
 181         goto end;
 182     }
 183     if (EVP_PKEY_CTX_set_rsa_keygen_primes(ctx, primes) <= 0) {
 184         BIO_printf(bio_err, "Error setting number of primes\n");
 185         goto end;
 186     }
 187     if (verbose)
 188         BIO_printf(bio_err, "Generating RSA private key, %d bit long modulus (%d primes)\n",
 189                    num, primes);
 190     if (!EVP_PKEY_keygen(ctx, &pkey)) {
 191         BIO_printf(bio_err, "Error generating RSA key\n");
 192         goto end;
 193     }
 194
 195     if (verbose) {
 196         if ((rsa = EVP_PKEY_get0_RSA(pkey)) != NULL) {
 197             RSA_get0_key(rsa, NULL, &e, NULL);
 198         } else {
 199             BIO_printf(bio_err, "Error cannot access RSA e\n");
 200             goto end;
 201         }
 202         hexe = BN_bn2hex(e);
 203         dece = BN_bn2dec(e);
 204         if (hexe && dece) {
 205             BIO_printf(bio_err, "e is %s (0x%s)\n", dece, hexe);
 206         }
 207         OPENSSL_free(hexe);
 208         OPENSSL_free(dece);
 209     }
 210     if (!PEM_write_bio_PrivateKey(out, pkey, enc, NULL, 0, NULL, passout))
 211         goto end;
 212
 213     ret = 0;
 214  end:
 215     BN_free(bn);
 216     BN_GENCB_free(cb);
 217     EVP_PKEY_CTX_free(ctx);
 218     EVP_PKEY_free(pkey);
 219     BIO_free_all(out);
 220     release_engine(eng);
 221     OPENSSL_free(passout);
 222     OPENSSL_free(ebuf);
 223     if (ret != 0)
 224         ERR_print_errors(bio_err);
 225     return ret;
 226 }
 227
 228 static int genrsa_cb(EVP_PKEY_CTX *ctx)
 229 {
 230     char c = '*';
 231     BIO *b = EVP_PKEY_CTX_get_app_data(ctx);
 232     int p = EVP_PKEY_CTX_get_keygen_info(ctx, 0);
 233
 234     if (!verbose)
 235         return 1;
 236
 237     if (p == 0)
 238         c = '.';
 239     if (p == 1)
 240         c = '+';
 241     if (p == 2)
 242         c = '*';
 243     if (p == 3)
 244         c = '\n';
 245     BIO_write(b, &c, 1);
 246     (void)BIO_flush(b);
 247     return 1;
 248 }