/* used by server */
int dh_generate_y(ssh_session session) {
session->next_crypto->y = bignum_new();
if (session->next_crypto->y == NULL) {
return -1;
}
#ifdef HAVE_LIBGCRYPT
bignum_rand(session->next_crypto->y, 128);
#elif defined HAVE_LIBCRYPTO
bignum_rand(session->next_crypto->y, 128, 0, -1);
#endif
/* not harder than this */
#ifdef DEBUG_CRYPTO
ssh_print_bignum("y", session->next_crypto->y);
#endif
return 0;
}
/** @brief generates a random integer between 0 and max
* @returns 1 in case of success, 0 otherwise
*/
int ssh_gcry_rand_range(bignum dest, bignum max)
{
size_t bits;
bignum rnd;
int rc;
bits = bignum_num_bits(max) + 64;
rnd = bignum_new();
if (rnd == NULL) {
return 0;
}
rc = bignum_rand(rnd, bits);
if (rc != 1) {
return rc;
}
gcry_mpi_mod(dest, rnd, max);
bignum_safe_free(rnd);
return 1;
}