wolfssl-examples/certgen/certgen_example.c

251 lines
8.3 KiB
C

#include <stdio.h>
#include <wolfssl/options.h>
#include <wolfssl/wolfcrypt/settings.h>
#include <wolfssl/wolfcrypt/ecc.h>
#include <wolfssl/wolfcrypt/asn_public.h>
#include <wolfssl/wolfcrypt/asn.h>
#include <wolfssl/wolfcrypt/error-crypt.h>
#define HEAP_HINT NULL
#define FOURK_SZ 4096
#if defined(WOLFSSL_CERT_REQ) && defined(WOLFSSL_CERT_GEN)
void free_things(byte** a, byte** b, byte** c, ecc_key* d, ecc_key* e,
WC_RNG* f);
#endif
int main(void) {
#if !defined(WOLFSSL_CERT_REQ) || !defined(WOLFSSL_CERT_GEN)
printf("Please compile wolfSSL with --enable-certreq --enable-certgen\n");
return 0;
#else
int ret = 0;
Cert newCert;
FILE* file;
char certToUse[] = "./ca-cert.der";
char caKeyFile[] = "./ca-key.der";
char newCertOutput[] = "./newCert.der";
int derBufSz;
int caKeySz;
byte* derBuf = NULL;
byte* pemBuf = NULL;
byte* caKeyBuf = NULL;
/* for MakeCert and SignCert */
WC_RNG rng;
ecc_key caKey;
ecc_key newKey;
word32 idx3 = 0;
/*---------------------------------------------------------------------------*/
/* open and read the der formatted certificate */
/*---------------------------------------------------------------------------*/
printf("Open and read in der formatted certificate\n");
derBuf = (byte*) XMALLOC(FOURK_SZ, HEAP_HINT, DYNAMIC_TYPE_TMP_BUFFER);
if (derBuf == NULL) goto fail;
XMEMSET(derBuf, 0, FOURK_SZ);
file = fopen(certToUse, "rb");
if (!file) {
printf("failed to find file: %s\n", certToUse);
goto fail;
}
derBufSz = fread(derBuf, 1, FOURK_SZ, file);
fclose(file);
printf("Successfully read %d bytes\n\n", derBufSz);
/*---------------------------------------------------------------------------*/
/* END */
/*---------------------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
/* open caKey file and get the caKey */
/*---------------------------------------------------------------------------*/
printf("Getting the caKey from %s\n", caKeyFile);
caKeyBuf = (byte*) XMALLOC(FOURK_SZ, HEAP_HINT, DYNAMIC_TYPE_TMP_BUFFER);
if (caKeyBuf == NULL) goto fail;
file = fopen(caKeyFile, "rb");
if (!file) {
printf("failed to open file: %s\n", caKeyFile);
goto fail;
}
caKeySz = fread(caKeyBuf, 1, FOURK_SZ, file);
if (caKeySz <= 0) {
printf("Failed to read caKey from file\n");
goto fail;
}
fclose(file);
printf("Successfully read %d bytes\n", caKeySz);
printf("Init ecc Key\n");
wc_ecc_init(&caKey);
printf("Decode the private key\n");
ret = wc_EccPrivateKeyDecode(caKeyBuf, &idx3, &caKey, (word32)caKeySz);
if (ret != 0) goto fail;
printf("Successfully retrieved caKey\n\n");
/*---------------------------------------------------------------------------*/
/* END */
/*---------------------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
/* Generate new ecc key */
/*---------------------------------------------------------------------------*/
printf("initializing the rng\n");
ret = wc_InitRng(&rng);
if (ret != 0) goto fail;
printf("Generating a new ecc key\n");
ret = wc_ecc_init(&newKey);
if (ret != 0) goto fail;
ret = wc_ecc_make_key(&rng, 32, &newKey);
if (ret != 0) goto fail;
printf("Successfully created new ecc key\n\n");
/*---------------------------------------------------------------------------*/
/* END */
/*---------------------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
/* Create a new certificate using header information from der cert */
/*---------------------------------------------------------------------------*/
printf("Setting new cert issuer to subject of signer\n");
wc_InitCert(&newCert);
strncpy(newCert.subject.country, "US", CTC_NAME_SIZE);
strncpy(newCert.subject.state, "MT", CTC_NAME_SIZE);
strncpy(newCert.subject.locality, "Bozeman", CTC_NAME_SIZE);
strncpy(newCert.subject.org, "yourOrgNameHere", CTC_NAME_SIZE);
strncpy(newCert.subject.unit, "yourUnitNameHere", CTC_NAME_SIZE);
strncpy(newCert.subject.commonName, "www.yourDomain.com", CTC_NAME_SIZE);
strncpy(newCert.subject.email, "yourEmail@yourDomain.com", CTC_NAME_SIZE);
newCert.isCA = 0;
newCert.sigType = CTC_SHA256wECDSA;
ret = wc_SetIssuerBuffer(&newCert, derBuf, derBufSz);
if (ret != 0) goto fail;
ret = wc_MakeCert(&newCert, derBuf, FOURK_SZ, NULL, &newKey, &rng); //ecc certificate
if (ret < 0) goto fail;
printf("MakeCert returned %d\n", ret);
ret = wc_SignCert(newCert.bodySz, newCert.sigType, derBuf, FOURK_SZ, NULL,
&caKey, &rng);
if (ret < 0) goto fail;
printf("SignCert returned %d\n", ret);
derBufSz = ret;
printf("Successfully created new certificate\n");
/*---------------------------------------------------------------------------*/
/* END */
/*---------------------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
/* write the new cert to file in der format */
/*---------------------------------------------------------------------------*/
printf("Writing newly generated certificate to file \"%s\"\n",
newCertOutput);
file = fopen(newCertOutput, "wb");
if (!file) {
printf("failed to open file: %s\n", newCertOutput);
goto fail;
}
ret = (int) fwrite(derBuf, 1, derBufSz, file);
fclose(file);
printf("Successfully output %d bytes\n", ret);
/*---------------------------------------------------------------------------*/
/* END */
/*---------------------------------------------------------------------------*/
/*---------------------------------------------------------------------------*/
/* convert the der to a pem and write it to a file */
/*---------------------------------------------------------------------------*/
{
char pemOutput[] = "./newCert.pem";
int pemBufSz;
printf("Convert the der cert to pem formatted cert\n");
pemBuf = (byte*) XMALLOC(FOURK_SZ, HEAP_HINT, DYNAMIC_TYPE_TMP_BUFFER);
if (pemBuf == NULL) goto fail;
XMEMSET(pemBuf, 0, FOURK_SZ);
pemBufSz = wc_DerToPem(derBuf, derBufSz, pemBuf, FOURK_SZ, CERT_TYPE);
if (pemBufSz < 0) goto fail;
printf("Resulting pem buffer is %d bytes\n", pemBufSz);
file = fopen(pemOutput, "wb");
if (!file) {
printf("failed to open file: %s\n", pemOutput);
goto fail;
}
fwrite(pemBuf, 1, pemBufSz, file);
fclose(file);
printf("Successfully converted the der to pem. Result is in: %s\n\n",
pemOutput);
}
/*---------------------------------------------------------------------------*/
/* END */
/*---------------------------------------------------------------------------*/
goto success;
fail:
free_things(&derBuf, &pemBuf, &caKeyBuf, &caKey, &newKey, &rng);
printf("Failure code was %d\n", ret);
return -1;
success:
free_things(&derBuf, &pemBuf, &caKeyBuf, &caKey, &newKey, &rng);
printf("Tests passed\n");
return 0;
}
void free_things(byte** a, byte** b, byte** c, ecc_key* d, ecc_key* e,
WC_RNG* f)
{
if (a != NULL) {
if (*a != NULL) {
XFREE(*a, HEAP_HINT, DYNAMIC_TYPE_TMP_BUFFER);
*a = NULL;
}
}
if (b != NULL) {
if (*b != NULL) {
XFREE(*b, HEAP_HINT, DYNAMIC_TYPE_TMP_BUFFER);
*b = NULL;
}
}
if (c != NULL) {
if (*c != NULL) {
XFREE(*c, HEAP_HINT, DYNAMIC_TYPE_TMP_BUFFER);
*c = NULL;
}
}
wc_ecc_free(d);
wc_ecc_free(e);
wc_FreeRng(f);
#endif
}