How to derive a key with JCA/JCE and with an HSM

Question

I have a master key in an HSM and I want to derive it with a given diversifier. I am quite new to JCA/JCE, and a bit lost with KeyGenerator, SecretKeyFactory, ... especially since all parameters are strings. I want to use AES or HmacSha1. It seems I need to use a SecretKeyFactory, and provide a KeySpecs. But which type of KeySpecs?

(I have seen a post on that topic, but I didn't seem an HSM was used.)

Thanks.

Answer 1

You can derive key using:

• password-based derivation (PKCS#5) as described in Deriving a secret from a master key using JCE/JCA or
• emulate C_Derive from PKCS#11 using encryption as described in PKCS11 deriveKey() and encrypt() returning different results for 3DES

to use HSM from JCA/JCE APIs, you need to add the corresponding provider to the JCA/JCE APIs and then specify the the provider parameter to request for that specific provider implementation.

For example:

int slot = 0;
Provider provider = new au.com.safenet.crypto.provider.SAFENETProvider(slot);
Security.addProvider(provider);
final String PROVIDER = provider.getName(); // "SAFENET", "SAFENET.1", ...

KeyGenerator keyGen = KeyGenerator.getInstance("DESede", PROVIDER);
Key baseKey = keyGen.generateKey();

Cipher desCipher = Cipher.getInstance("DESede/CBC/PKCS5Padding", PROVIDER);
desCipher.init(Cipher.ENCRYPT_MODE, baseKey);

byte[] derived = desCipher.doFinal("diversification data".getBytes());

Note that if you need to do key derivation very often, you might consider to use your provider's PCKS#11 wrapper for Java (e.g. jcprov from SafeNet) or other APIs so that you can be more explicit about its session management and be more efficient about resource usage.