From what I understand, in general, TLS consists of two protocols:
1 - Handshake protocol: uses public-key cryptography (ECDH, DH) to establish a shared secret between the client and server.
2 - Record protocol: uses the shared secret established in the handshake protocol to protect communication or application data between the client and server
Let's say I want to encrypt data and then use steganography to hide the encrypted data in an image, then I want to exchange the key used with the server using the handshake protocol BUT I do not want to send the steganographic image using the record protocol because it would defeat the purpose.
So, can I simply complete the handshake protocol and then drop the connection?