Trying to sign a hash like the C# method SignHash about pkcs11interop HOT 2 CLOSED

Addendum : I followed your sample code here : https://github.com/jariq/Pkcs11Interop.PDF/blob/8f7015ed4231344c02706fc1161f217fce961264/src/Pkcs11Interop.PDF/Pkcs11RsaSignature.cs

And I added this before signing :

byte[] digestInfo = null;
byte[] digest = null;
digest = ComputeDigest(new Sha256Digest(), btToSign);
digestInfo = CreateDigestInfo(digest, "2.16.840.1.101.3.4.2.1");
btResult = session.Sign(new Mechanism(CKM.CKM_RSA_PKCS), handlePrivateKey, digestInfo);

But this operation returns the following error CKR_FUNCTION_FAILED. Maybe the length of the digestInfo byte array (49 bytes) is not good for signing like this ?

from pkcs11interop.

I understand what happened. Regarding this thread :

http://stackoverflow.com/questions/33305800/difference-between-sha256withrsa-and-sha256-then-rsa?noredirect=1&lq=1

The method "CreateDigestInfo" should have a line containing the parameter DerNull.Instance instead of null, like this :

AlgorithmIdentifier algorithmIdentifier = new AlgorithmIdentifier(derObjectIdentifier, DerNull.Instance);

instead of this :

AlgorithmIdentifier algorithmIdentifier = new AlgorithmIdentifier(derObjectIdentifier, null);

This issue can be closed (maybe it will be useful for someone else).

from pkcs11interop.