wolfssl-examples/pk/srp/srp_gen.c

126 lines
3.1 KiB
C

/* srp_gen.c
*
* Copyright (C) 2006-2020 wolfSSL Inc.
*
* This file is part of wolfSSL. (formerly known as CyaSSL)
*
* wolfSSL is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* wolfSSL is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
*/
#ifndef WOLFSSL_USER_SETTINGS
#include <wolfssl/options.h>
#endif
#include <wolfssl/wolfcrypt/settings.h>
#include <wolfssl/wolfcrypt/srp.h>
#include <stdio.h>
#ifdef WOLFCRYPT_HAVE_SRP
#include "srp_params.h"
/* Generate a new random salt */
static int generate_random_salt(byte *buf, word32 size)
{
int ret;
WC_RNG rng;
ret = wc_InitRng(&rng);
if (ret == 0) {
ret = wc_RNG_GenerateBlock(&rng, (byte *)buf, size);
wc_FreeRng(&rng);
}
return ret;
}
/* Print out the buffer as a C variable */
static void print_buf(char *name, byte* buf, word32 sz)
{
int i;
printf("static const byte %s[%d] = {", name, sz);
for (i = 0; i < (int)sz; i++) {
if ((i % 12) == 0) {
printf("\n ");
}
printf("0x%02x,", buf[i]);
}
printf("\n};\n");
}
int main(int argc, char* argv[])
{
int ret;
Srp srp;
byte salt[20];
byte verifier[80];
word32 vSz = (word32)sizeof(verifier);
char* username;
char* password;
if (argc < 3) {
fprintf(stderr, "usage: %s <username> <password>\n", argv[0]);
return 1;
}
username = argv[1];
password = argv[2];
ret = generate_random_salt(salt, sizeof(salt));
if (ret == 0) {
ret = wc_SrpInit(&srp, SRP_TYPE_SHA, SRP_CLIENT_SIDE);
}
if (ret == 0) {
ret = wc_SrpSetUsername(&srp, (byte*)username, XSTRLEN(username));
if (ret == 0) {
ret = wc_SrpSetParams(&srp, srp_n_640, sizeof(srp_n_640),
srp_g_640, sizeof(srp_g_640),
salt, sizeof(salt));
}
if (ret == 0) {
ret = wc_SrpSetPassword(&srp, (byte*)password, XSTRLEN(password));
}
if (ret == 0) {
ret = wc_SrpGetVerifier(&srp, verifier, &vSz);
}
wc_SrpTerm(&srp);
}
/* Output the details to store on the server */
printf("static const char* srp_username = \"%s\";\n", username);
print_buf("salt", salt, sizeof(salt));
print_buf("verifier", verifier, vSz);
return (ret == 0) ? 0 : 1;
}
#else
int main(int argc, char* argv[])
{
(void)argc;
(void)argv;
fprintf(stderr, "Must build wolfSSL with SRP enabled for this example\n");
return 0;
}
#endif