On 09/11/2015 08:44 AM, Chris Adams wrote:
Once upon a time, Alice Wonder alice@domblogger.net said:
They recommend setting the following:
KexAlgorithms curve25519-sha256@libssh.org
I don't even see that directive in my sshd config to set it, I suppose it may be one that is manually added when needed but I want to verify it actually means something in CentOS 7 ssh.
Also I'm a little worried that maybe curve25519 is one of the curves that Red Hat (and thus CentOS 7) doesn't support due to patent concerns.
That is supported in the CentOS 7 version of OpenSSH. Look at the man page for sshd_config and you'll see the KexAlgorithms option listed and its valid values. You can always see what your exact copy and config of OpenSSH are using by running "sshd -T".
However, if you set it as above, you would _only_ be able to connect with that algorithm, and not all SSH clients support that (even for example OpenSSH on CentOS 6).
Thanks - what I ended up doing is:
KexAlgorithms curve25519-sha256@libssh.org,diffie-hellman-group-exchange-sha256
Then I generated fresh 2048 and 4096 primes for the moduli file.
So far it seems all the ssh clients I have tried work.