chrome.socket
doesn't provide built-in SSL support (yet anyways, see http://crbug.com/132896), you need to add the SSL encoding / decoding in your application. Once the TCP connection is established you can begin the SSL negotiation (i.e. after chrome.sockets.tcp.connect calls your callback function).
I recently added SSL support to CIRC using the forge javascript library which implements SSL in JS. You can see the complete wrapping of a chrome socket connection in CIRC here: https://github.com/flackr/circ/blob/master/package/bin/net/ssl_socket.js
Note, that I haven't actually added identity verification, see verify: options.verify || function() { return true }
, but this could be replaced with an appropriate verification function.