apps/prime.c

   1 /*
   2  * Copyright 2004-2022 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 <string.h>
  11
  12 #include "apps.h"
  13 #include "progs.h"
  14 #include <openssl/bn.h>
  15
  16 typedef enum OPTION_choice {
  17     OPT_COMMON,
  18     OPT_HEX, OPT_GENERATE, OPT_BITS, OPT_SAFE, OPT_CHECKS,
  19     OPT_PROV_ENUM
  20 } OPTION_CHOICE;
  21
  22 static int check_num(const char *s, const int is_hex)
  23 {
  24     int i;
  25     /*
  26      * It would make sense to use ossl_isxdigit and ossl_isdigit here,
  27      * but ossl_ctype_check is a local symbol in libcrypto.so.
  28      */
  29     if (is_hex) {
  30         for (i = 0; ('0' <= s[i] && s[i] <= '9')
  31                     || ('A' <= s[i] && s[i] <= 'F')
  32                     || ('a' <= s[i] && s[i] <= 'f'); i++);
  33     } else {
  34         for (i = 0;  '0' <= s[i] && s[i] <= '9'; i++);
  35     }
  36     return s[i] == 0;
  37 }
  38
  39 const OPTIONS prime_options[] = {
  40     {OPT_HELP_STR, 1, '-', "Usage: %s [options] [number...]\n"},
  41
  42     OPT_SECTION("General"),
  43     {"help", OPT_HELP, '-', "Display this summary"},
  44     {"bits", OPT_BITS, 'p', "Size of number in bits"},
  45     {"checks", OPT_CHECKS, 'p', "Number of checks"},
  46
  47     OPT_SECTION("Output"),
  48     {"hex", OPT_HEX, '-', "Hex output"},
  49     {"generate", OPT_GENERATE, '-', "Generate a prime"},
  50     {"safe", OPT_SAFE, '-',
  51      "When used with -generate, generate a safe prime"},
  52
  53     OPT_PROV_OPTIONS,
  54
  55     OPT_PARAMETERS(),
  56     {"number", 0, 0, "Number(s) to check for primality if not generating"},
  57     {NULL}
  58 };
  59
  60 int prime_main(int argc, char **argv)
  61 {
  62     BIGNUM *bn = NULL;
  63     int hex = 0, generate = 0, bits = 0, safe = 0, ret = 1;
  64     char *prog;
  65     OPTION_CHOICE o;
  66
  67     prog = opt_init(argc, argv, prime_options);
  68     while ((o = opt_next()) != OPT_EOF) {
  69         switch (o) {
  70         case OPT_EOF:
  71         case OPT_ERR:
  72 opthelp:
  73             BIO_printf(bio_err, "%s: Use -help for summary.\n", prog);
  74             goto end;
  75         case OPT_HELP:
  76             opt_help(prime_options);
  77             ret = 0;
  78             goto end;
  79         case OPT_HEX:
  80             hex = 1;
  81             break;
  82         case OPT_GENERATE:
  83             generate = 1;
  84             break;
  85         case OPT_BITS:
  86             bits = atoi(opt_arg());
  87             break;
  88         case OPT_SAFE:
  89             safe = 1;
  90             break;
  91         case OPT_CHECKS:
  92             /* ignore parameter and argument */
  93             opt_arg();
  94             break;
  95         case OPT_PROV_CASES:
  96             if (!opt_provider(o))
  97                 goto end;
  98             break;
  99         }
 100     }
 101
 102     /* Optional arguments are numbers to check. */
 103     if (generate && !opt_check_rest_arg(NULL))
 104         goto opthelp;
 105     argc = opt_num_rest();
 106     argv = opt_rest();
 107     if (!generate && argc == 0) {
 108         BIO_printf(bio_err, "Missing number (s) to check\n");
 109         goto opthelp;
 110     }
 111
 112     if (generate) {
 113         char *s;
 114
 115         if (!bits) {
 116             BIO_printf(bio_err, "Specify the number of bits.\n");
 117             goto end;
 118         }
 119         bn = BN_new();
 120         if (bn == NULL) {
 121             BIO_printf(bio_err, "Out of memory.\n");
 122             goto end;
 123         }
 124         if (!BN_generate_prime_ex(bn, bits, safe, NULL, NULL, NULL)) {
 125             BIO_printf(bio_err, "Failed to generate prime.\n");
 126             goto end;
 127         }
 128         s = hex ? BN_bn2hex(bn) : BN_bn2dec(bn);
 129         if (s == NULL) {
 130             BIO_printf(bio_err, "Out of memory.\n");
 131             goto end;
 132         }
 133         BIO_printf(bio_out, "%s\n", s);
 134         OPENSSL_free(s);
 135     } else {
 136         for ( ; *argv; argv++) {
 137             int r = check_num(argv[0], hex);
 138
 139             if (r)
 140                 r = hex ? BN_hex2bn(&bn, argv[0]) : BN_dec2bn(&bn, argv[0]);
 141
 142             if (!r) {
 143                 BIO_printf(bio_err, "Failed to process value (%s)\n", argv[0]);
 144                 goto end;
 145             }
 146
 147             BN_print(bio_out, bn);
 148             BIO_printf(bio_out, " (%s) %s prime\n",
 149                        argv[0],
 150                        BN_check_prime(bn, NULL, NULL)
 151                            ? "is" : "is not");
 152         }
 153     }
 154
 155     ret = 0;
 156  end:
 157     BN_free(bn);
 158     return ret;
 159 }