Hi. On Mon, Jun 11, 2018 at 08:04:35AM -0400, Jim Popovitch wrote: > On Mon, 2018-06-11 at 14:51 +0300, Reco wrote: > > Hi. > > > > On Mon, Jun 11, 2018 at 07:12:32AM -0400, Jim Popovitch wrote: > > > On Sun, 2018-06-10 at 14:27 +0300, Reco wrote: > > > > > > > > Ciphers chacha20-poly1...@openssh.com,aes256-...@openssh.com > > > > > > What's your thoughts on extending that a bit by adding aes256-ctr > > > to > > > that list? > > > > Don't use it, unless compatibility with certain Windows SSH clients > > is > > required. [1] is a good read on this Cipher. > > What I can consider is ADEAD variety of AES, but - I'm uncertain > > whenever it made its way to OpenSSH at all. It's not in Stretch's > > version of openssh, that's for sure. > > > > Hmmm. I was reading [1] earlier and felt that "Don't use it" applied > to CBC but not CTR. I use ConnectBot (Android SSH client app) and it > has a limited set of ciphers.
I have two considerations on this then: 1) Abforementioned link says that (and that applies to aes256-ctr): * nonce reuse is catastrophic, confidentiality is completely lost * leaks somewhat more information about the size of the plaintext Second I can live with, but first is a big "no" in my book. 2) ConnectBot is nice, but I prefer Termux with a proper Debian chroot over it. That way I'm certain that all the deficiencies/vulnerabilities discovered in a foreseeable future receive a timely update. Reco