quickjs-tart

quickjs-based runtime for wallet-core logic
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dh_genprime.c (4640B)

      1 /*
      2  *  Diffie-Hellman-Merkle key exchange (prime generation)
      3  *
      4  *  Copyright The Mbed TLS Contributors
      5  *  SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
      6  */
      7 
      8 #include "mbedtls/build_info.h"
      9 
     10 #include "mbedtls/platform.h"
     11 
     12 #if !defined(MBEDTLS_BIGNUM_C) || !defined(MBEDTLS_ENTROPY_C) ||   \
     13     !defined(MBEDTLS_FS_IO) || !defined(MBEDTLS_CTR_DRBG_C) ||     \
     14     !defined(MBEDTLS_GENPRIME)
     15 int main(void)
     16 {
     17     mbedtls_printf("MBEDTLS_BIGNUM_C and/or MBEDTLS_ENTROPY_C and/or "
     18                    "MBEDTLS_FS_IO and/or MBEDTLS_CTR_DRBG_C and/or "
     19                    "MBEDTLS_GENPRIME not defined.\n");
     20     mbedtls_exit(0);
     21 }
     22 #else
     23 
     24 #include "mbedtls/bignum.h"
     25 #include "mbedtls/entropy.h"
     26 #include "mbedtls/ctr_drbg.h"
     27 
     28 #include <stdio.h>
     29 #include <string.h>
     30 
     31 #define USAGE \
     32     "\n usage: dh_genprime param=<>...\n"                                   \
     33     "\n acceptable parameters:\n"                                           \
     34     "    bits=%%d           default: 2048\n"
     35 
     36 #define DFL_BITS    2048
     37 
     38 /*
     39  * Note: G = 4 is always a quadratic residue mod P,
     40  * so it is a generator of order Q (with P = 2*Q+1).
     41  */
     42 #define GENERATOR "4"
     43 
     44 
     45 int main(int argc, char **argv)
     46 {
     47     int ret = 1;
     48     int exit_code = MBEDTLS_EXIT_FAILURE;
     49     mbedtls_mpi G, P, Q;
     50     mbedtls_entropy_context entropy;
     51     mbedtls_ctr_drbg_context ctr_drbg;
     52     const char *pers = "dh_genprime";
     53     FILE *fout;
     54     int nbits = DFL_BITS;
     55     int i;
     56     char *p, *q;
     57 
     58     mbedtls_mpi_init(&G); mbedtls_mpi_init(&P); mbedtls_mpi_init(&Q);
     59     mbedtls_ctr_drbg_init(&ctr_drbg);
     60     mbedtls_entropy_init(&entropy);
     61 
     62     if (argc < 2) {
     63 usage:
     64         mbedtls_printf(USAGE);
     65         goto exit;
     66     }
     67 
     68     for (i = 1; i < argc; i++) {
     69         p = argv[i];
     70         if ((q = strchr(p, '=')) == NULL) {
     71             goto usage;
     72         }
     73         *q++ = '\0';
     74 
     75         if (strcmp(p, "bits") == 0) {
     76             nbits = atoi(q);
     77             if (nbits < 0 || nbits > MBEDTLS_MPI_MAX_BITS) {
     78                 goto usage;
     79             }
     80         } else {
     81             goto usage;
     82         }
     83     }
     84 
     85     if ((ret = mbedtls_mpi_read_string(&G, 10, GENERATOR)) != 0) {
     86         mbedtls_printf(" failed\n  ! mbedtls_mpi_read_string returned %d\n", ret);
     87         goto exit;
     88     }
     89 
     90     mbedtls_printf("  ! Generating large primes may take minutes!\n");
     91 
     92     mbedtls_printf("\n  . Seeding the random number generator...");
     93     fflush(stdout);
     94 
     95     if ((ret = mbedtls_ctr_drbg_seed(&ctr_drbg, mbedtls_entropy_func, &entropy,
     96                                      (const unsigned char *) pers,
     97                                      strlen(pers))) != 0) {
     98         mbedtls_printf(" failed\n  ! mbedtls_ctr_drbg_seed returned %d\n", ret);
     99         goto exit;
    100     }
    101 
    102     mbedtls_printf(" ok\n  . Generating the modulus, please wait...");
    103     fflush(stdout);
    104 
    105     /*
    106      * This can take a long time...
    107      */
    108     if ((ret = mbedtls_mpi_gen_prime(&P, nbits, 1,
    109                                      mbedtls_ctr_drbg_random, &ctr_drbg)) != 0) {
    110         mbedtls_printf(" failed\n  ! mbedtls_mpi_gen_prime returned %d\n\n", ret);
    111         goto exit;
    112     }
    113 
    114     mbedtls_printf(" ok\n  . Verifying that Q = (P-1)/2 is prime...");
    115     fflush(stdout);
    116 
    117     if ((ret = mbedtls_mpi_sub_int(&Q, &P, 1)) != 0) {
    118         mbedtls_printf(" failed\n  ! mbedtls_mpi_sub_int returned %d\n\n", ret);
    119         goto exit;
    120     }
    121 
    122     if ((ret = mbedtls_mpi_div_int(&Q, NULL, &Q, 2)) != 0) {
    123         mbedtls_printf(" failed\n  ! mbedtls_mpi_div_int returned %d\n\n", ret);
    124         goto exit;
    125     }
    126 
    127     if ((ret = mbedtls_mpi_is_prime_ext(&Q, 50, mbedtls_ctr_drbg_random, &ctr_drbg)) != 0) {
    128         mbedtls_printf(" failed\n  ! mbedtls_mpi_is_prime returned %d\n\n", ret);
    129         goto exit;
    130     }
    131 
    132     mbedtls_printf(" ok\n  . Exporting the value in dh_prime.txt...");
    133     fflush(stdout);
    134 
    135     if ((fout = fopen("dh_prime.txt", "wb+")) == NULL) {
    136         mbedtls_printf(" failed\n  ! Could not create dh_prime.txt\n\n");
    137         goto exit;
    138     }
    139 
    140     if (((ret = mbedtls_mpi_write_file("P = ", &P, 16, fout)) != 0) ||
    141         ((ret = mbedtls_mpi_write_file("G = ", &G, 16, fout)) != 0)) {
    142         mbedtls_printf(" failed\n  ! mbedtls_mpi_write_file returned %d\n\n", ret);
    143         fclose(fout);
    144         goto exit;
    145     }
    146 
    147     mbedtls_printf(" ok\n\n");
    148     fclose(fout);
    149 
    150     exit_code = MBEDTLS_EXIT_SUCCESS;
    151 
    152 exit:
    153 
    154     mbedtls_mpi_free(&G); mbedtls_mpi_free(&P); mbedtls_mpi_free(&Q);
    155     mbedtls_ctr_drbg_free(&ctr_drbg);
    156     mbedtls_entropy_free(&entropy);
    157 
    158     mbedtls_exit(exit_code);
    159 }
    160 #endif /* MBEDTLS_BIGNUM_C && MBEDTLS_ENTROPY_C && MBEDTLS_FS_IO &&
    161           MBEDTLS_CTR_DRBG_C && MBEDTLS_GENPRIME */