Thread: Generate digital signature from a string

Can you post the code you are having problems with and describe what the problem is?

It's really long and complicated. Let me rephrase the question:
- I, the client, have generated a self-signed certificate with private key using openssl.
- The certificate has been imported to the server to which I need to do http Get and Post requests (which will be signed - with a signature parameter passed) - and the certificate will be used to verify the signature.
- I generated the signature from a message using the private key.

My question is, do I need to use the certificate from my side for generating the digital signature? or the private key is enough? How the server will recognize what certificate to use for verification? This is the first time I work with certificates.

Here's the simple code I use:

String message = 'some message'
//Load the private key from pem file
PrivateKey privateKey = loadPrivateKey()
//Sign the message
Signature signature = Signature.getInstance("SHA256withRSA")
signature.initSign(privateKey);
signature.update(message.getBytes());
byte[] signedMsg = signature.sign();

Thanks in advance

Sorry, I don't know anything about servers and certificates.