wolfssl-examples/certfields/main.c

141 lines
4.4 KiB
C

/* main.c
*
* Copyright (C) 2006-2020 wolfSSL Inc.
*
* This file is part of wolfSSL.
*
* 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 02110-1335, USA
*/
/*
* Example of parsing a DER-encoded certificate and extracting
* public key and subject name information.
*
*/
#include <stdio.h>
#include <wolfssl/options.h>
#include <wolfssl/ssl.h>
#include <wolfssl/wolfcrypt/rsa.h>
#include <wolfssl/wolfcrypt/asn.h>
static void err_sys(const char* msg, int ret)
{
if (ret) {
printf("ERROR: %s, ret = %d\n", msg, ret);
} else {
printf("ERROR: %s\n", msg);
}
exit(EXIT_FAILURE);
}
int main(void)
{
int ret, i;
int sigType;
int nameSz;
int derCertSz;
byte derCert[4096];
word32 idx;
FILE* file;
RsaKey pubKey;
WOLFSSL_X509* cert;
WOLFSSL_EVP_PKEY* pubKeyTmp;
WOLFSSL_X509_NAME* name;
char commonName[80];
char countryName[80];
char localityName[80];
char stateName[80];
char orgName[80];
char orgUnit[80];
/* ------ PARSE ORIGINAL SELF-SIGNED CERTIFICATE ------ */
/* open and read DER-formatted cert into buffer */
file = fopen("../certs/client-cert.der", "rb");
if (!file)
err_sys("can't open client certificate", 0);
derCertSz = fread(derCert, 1, sizeof(derCert), file);
fclose(file);
/* convert cert from DER to internal WOLFSSL_X509 struct */
cert = wolfSSL_X509_d2i(&cert, derCert, derCertSz);
if (cert == NULL)
err_sys("Failed to convert DER to WOLFSSL_X509", 0);
/* ------ EXTRACT CERTIFICATE ELEMENTS ------ */
/* extract PUBLIC KEY from cert */
pubKeyTmp = wolfSSL_X509_get_pubkey(cert);
if (pubKeyTmp == NULL)
err_sys("wolfSSL_X509_get_pubkey failed", 0);
wc_InitRsaKey(&pubKey, 0);
idx = 0;
ret = wc_RsaPublicKeyDecode((byte*)pubKeyTmp->pkey.ptr, &idx, &pubKey,
pubKeyTmp->pkey_sz);
if (ret != 0)
err_sys("wc_RsaPublicKeyDecode failed", ret);
printf("PUBLIC KEY:\n");
for (i = 0; i < pubKeyTmp->pkey_sz; i++) {
printf("%02X", pubKeyTmp->pkey.ptr[i] & 0xFF);
} printf("\n");
/* extract signatureType */
sigType = wolfSSL_X509_get_signature_type(cert);
if (sigType == 0)
err_sys("wolfSSL_X509_get_signature_type failed", 0);
printf("SIG TYPE = %d\n", sigType);
/* extract subjectName info */
name = wolfSSL_X509_get_subject_name(cert);
if (name == NULL)
err_sys("wolfSSL_X509_get_subject_name failed", 0);
nameSz = wolfSSL_X509_NAME_get_text_by_NID(name, ASN_COMMON_NAME,
commonName, sizeof(commonName));
printf("CN = %s (%d)\n", commonName, nameSz);
nameSz = wolfSSL_X509_NAME_get_text_by_NID(name, ASN_COUNTRY_NAME,
countryName, sizeof(countryName));
printf("COUNTRY = %s (%d)\n", countryName, nameSz);
nameSz = wolfSSL_X509_NAME_get_text_by_NID(name, ASN_LOCALITY_NAME,
localityName, sizeof(localityName));
printf("LOCALITY = %s (%d)\n", localityName, nameSz);
nameSz = wolfSSL_X509_NAME_get_text_by_NID(name, ASN_STATE_NAME,
stateName, sizeof(stateName));
printf("STATE = %s (%d)\n", stateName, nameSz);
nameSz = wolfSSL_X509_NAME_get_text_by_NID(name, ASN_ORG_NAME,
orgName, sizeof(orgName));
printf("ORG = %s (%d)\n", orgName, nameSz);
nameSz = wolfSSL_X509_NAME_get_text_by_NID(name, ASN_ORGUNIT_NAME,
orgUnit, sizeof(orgUnit));
printf("ORG UNIT = %s (%d)\n", orgUnit, nameSz);
wolfSSL_EVP_PKEY_free(pubKeyTmp);
wolfSSL_X509_free(cert);
return 0;
}