Custom Sign Callback for ECC TLS Handshake

["nocommercials@xxxxxxxxxxx" <nocommercials@xxxxxxxxxxx>]

Hey there,

 

I currently create a program that does a TLS handshake using ECC certificates.

The private key is not accessible to that program so that I could load it into openssl and hence the sign step during handshake has to be offloaded to another component in the system.

For that purpose I do not find a callback or something.

What would be the correct way to achive this?
The way to have the data signed is non-standard, so I cannot use some standard such as PKCS11 or something.

 

I am glad to get just pointed to where to start with, rest I can figure out.

Thanks!