EVP_PKEY from char buffer in x509 (PKCS7)
- by sid
Hi All,
I have a DER certificate from which I am retrieving the Public key in unsigned char buffer as following, is it the right way of getting?
pStoredPublicKey = X509_get_pubkey(x509);
if(pStoredPublicKey == NULL)
{
printf(": publicKey is NULL\n");
}
if(pStoredPublicKey->type == EVP_PKEY_RSA) {
RSA *x = pStoredPublicKey->pkey.rsa;
bn = x->n;
}
else if(pStoredPublicKey->type == EVP_PKEY_DSA) {
}
else if(pStoredPublicKey->type == EVP_PKEY_EC) {
}
else {
printf(" : Unkown publicKey\n");
}
//extracts the bytes from public key & convert into unsigned char buffer
buf_len = (size_t) BN_num_bytes (bn);
key = (unsigned char *)malloc (buf_len);
n = BN_bn2bin (bn, (unsigned char *) key);
for (i = 0; i < n; i++)
{
printf("%02x\n", (unsigned char) key[i]);
}
keyLen = EVP_PKEY_size(pStoredPublicKey);
EVP_PKEY_free(pStoredPublicKey);
And, With this unsigned char buffer, How do I get back the EVP_PKEY for RSA?
OR Can I use following ???,
EVP_PKEY *d2i_PublicKey(int type, EVP_PKEY **a, unsigned char **pp, long length);
int i2d_PublicKey(EVP_PKEY *a, unsigned char **pp);
