X509* certificate serialization and deserialization in C - c

Question

I have a certificate in 509* format and I want to serialize it into a char buffer and then later desserialize it in other to recover the certificate 509* again.
I am doing it like this to serialize:
int size_cert = 0;
unsigned char* data;
BIO* bio = BIO_new(BIO_s_mem());
PEM_write_bio_X509(bio,certificate);
size_cert = BIO_get_mem_data(bio, &data);
BIO_free(bio);
where data should have the certificate data!
To reconstruct the X509* certificate back from the data buffer I am doing this:
BIO* bio;
X509* cert;
bio = BIO_new(BIO_s_mem());
BIO_puts(bio, data);
cert = PEM_read_bio_X509(bio, NULL, NULL, NULL);
Where cert should get the certificate. This is not working properly, can some one give me a good example for this?

Answer 1

I have done it with the below code,
1 Load certificate to BIO using BIO_read_filename
2 convert it to x509 using PEM_read_bio_X509_AUX
3 convert it to unsigned char* using i2d_X509
4 reconstruct the x509 from unsigned char* using d2i_X509
int main()
{
X509 *x509,*x509ser;
BIO *certBio = BIO_new(BIO_s_file());
char * path = "E:\\share\TempCert.pem"; // certificate path
int len;
unsigned char *buf;
buf = NULL;
BIO_read_filename(certBio, path); // reading certificate to bio
x509 = PEM_read_bio_X509_AUX(certBio, NULL, 0, NULL); //converting to x509
len = i2d_X509(x509, &buf); // converting to unsigned char*
x509ser = d2i_X509(NULL, &buf, len); // converting back to x509 from unsigned char*
BIO_free_all(certBio);
return 0;
}