[Bug 1771359] Re: No matching cipher found even if client and server have matching cipher

[Joseph Maillardet]

It's not a bug !

** Changed in: openssh (Ubuntu)
       Status: Incomplete => Invalid

** Converted to question:
   https://answers.launchpad.net/ubuntu/+source/openssh/+question/669164

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Title:
  No matching cipher found even if client and server have matching
  cipher

Status in openssh package in Ubuntu:
  Invalid

Bug description:
  Since Bionic upgrade (from Artful) I encounter problem to call HP
  switch with SSH.

  After the upgrade, trying to ssh some switch give me this message :

  $ ssh 192.168.0.1
  Unable to negotiate with 192.168.0.1 port 22: no matching cipher found. Their offer: aes128-cbc,3des-cbc,des-cbc

  So, I look for supported cipher :

  $ ssh -Q cipher
  3des-cbc
  aes128-cbc
  aes192-cbc
  aes256-cbc
  rijndael-cbc at lysator.liu.se
  aes128-ctr
  aes192-ctr
  aes256-ctr
  aes128-gcm at openssh.com
  aes256-gcm at openssh.com
  chacha20-poly1305 at openssh.com

  I see that aes128-cbc seem both supported. So I try... :

  $ ssh -c aes128-cbc 192.168.0.1

  ...and It's work !

  Workaround :

  I've added “ciphers aes128-cbc” to ~/.ssh/config file for each switch
  I manage.

  The ssh-client should detect automatically the good cipher ? No ?

  Thank you for your attention.

  ProblemType: Bug
  DistroRelease: Ubuntu 18.04
  Package: openssh-client 1:7.6p1-4
  ProcVersionSignature: Ubuntu 4.15.0-20.21-generic 4.15.17
  Uname: Linux 4.15.0-20-generic x86_64
  ApportVersion: 2.20.9-0ubuntu7
  Architecture: amd64
  CurrentDesktop: GNOME
  Date: Tue May 15 15:39:00 2018
  EcryptfsInUse: Yes
  ProcEnviron:
   TERM=xterm-256color
   PATH=(custom, no user)
   XDG_RUNTIME_DIR=<set>
   LANG=fr_FR.UTF-8
   SHELL=/bin/bash
  RelatedPackageVersions:
   ssh-askpass       N/A
   libpam-ssh        N/A
   keychain          N/A
   ssh-askpass-gnome 1:7.6p1-4
  SSHClientVersion: OpenSSH_7.6p1 Ubuntu-4, OpenSSL 1.0.2n  7 Dec 2017
  SourcePackage: openssh
  UpgradeStatus: Upgraded to bionic on 2018-04-24 (21 days ago)

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