When an SSH session is rekeyed due to either the time limit or data limit for rekeying having passed, does the Diffie-Hellman exchange take place within the encrypted channel provided by the existing session, or does it take place "in the open" the way it does when the client first connects to the SSH server?
Looking at the RFC for SSH and having read the output from ssh with the -vvv
option during a rekey, I still can't figure out the answer.
For the sake of this question, I'm mainly thinking about openssh in version above 6, if that matters.