Adding Server-Side TLS 1.0 Support - Implementing SSL/TLS Using Cryptography and PKI - page 402

Thus, the fi nal PKCS #8 structure looks like this:

OID_pbeWithMD5AndDES_CBC

salt

iteration count

bit string DES-Encrypted

OID_RSAPrivateKey

bit string

modulus (n)

public exponent (e)

private exponent (d)

prime1 (p)

prime2 (q)

exponent1 (d % p - 1)

exponent2 (e % q - 1)

coefficient (q^ - 1 %p)

Figure 7-2: PKCS #8-encoded private key file

To decode this, then, you must fi rst unwrap the top level structure and then
decrypt it to reveal the second level structure, and fi nally unwrap that to reveal
the key. Listing 7-17 illustrates this process for the case of an RSA private key
encrypted using PBE with DES/MD5.

Listing 7-17: “privkey.c” parse_pkcs8_private_key

static unsigned char OID_pbeWithMD5andDES_CBC[] =
{ 0x2a, 0x86, 0x48, 0x86, 0xf7, 0x0d, 0x01, 0x05, 0x03 };