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  1. Jenkins
  2. JENKINS-33021

trilead ssh MAC and key exchange algorithms severely outdated


    • Type: Improvement
    • Status: Resolved (View Workflow)
    • Priority: Critical
    • Resolution: Fixed
    • Component/s: ssh-slaves-plugin
    • Labels:
    • Environment:
      Jenkins 1.647, ssh-slaves-plugin 1.10
    • Similar Issues:


      The supported macs and kex methods in trilead are severely outdated, resulting in connection issues with properly secured ssh daemons on target machines. For instance:

      sshd[9800]: fatal: no matching mac found: client hmac-sha1-96,hmac-sha1,hmac-md5-96,hmac-md5 server hmac-sha2-256,hmac-sha2-512,umac-64@openssh.com,hmac-ripemd160 [preauth]

      In JENKINS-14709 a suggestion is made to replace trilead with orion, but Orion is not being maintained either. Orion refers to Ganymed, but even that hasn't been looked at for almost 2 years: Ganymed commits. It does seem to support hmac-sha2 macs though.

      From JENKINS-36873 (dupe)

      The ssh credentials plugin is unable to connect to slaves that have newer algorithms

      The keys from Jenkins (client) and slave (server below) have:

      fatal: no matching mac found:
      client: hmac-sha1-96,hmac-sha1,hmac-md5-96,hmac-md5
      server: hmac-sha2-512-etm@openssh.com,hmac-sha2-256-etm@openssh.com,umac-128-etm@openssh.com,hmac-sha2-512,hmac-sha2-256,umac-128@openssh.com [preauth]

      Jenkins yields a trace:

      [06/22/15 14:49:05] [SSH] Opening SSH connection to
      Key exchange was not finished, connection is closed.
      ERROR: Unexpected error in launching a slave. This is probably a bug in Jenkins.
      java.lang.IllegalStateException: Connection is not established!
      	at com.trilead.ssh2.Connection.getRemainingAuthMethods(Connection.java:1030)
      	at com.cloudbees.jenkins.plugins.sshcredentials.impl.TrileadSSHPublicKeyAuthenticator.getRemainingAuthMethods(TrileadSSHPublicKeyAuthenticator.java:88)
      	at com.cloudbees.jenkins.plugins.sshcredentials.impl.TrileadSSHPublicKeyAuthenticator.canAuthenticate(TrileadSSHPublicKeyAuthenticator.java:80)
      	at com.cloudbees.jenkins.plugins.sshcredentials.SSHAuthenticator.newInstance(SSHAuthenticator.java:207)
      	at com.cloudbees.jenkins.plugins.sshcredentials.SSHAuthenticator.newInstance(SSHAuthenticator.java:169)
      	at hudson.plugins.sshslaves.SSHLauncher.openConnection(SSHLauncher.java:1173)
      	at hudson.plugins.sshslaves.SSHLauncher$2.call(SSHLauncher.java:701)
      	at hudson.plugins.sshslaves.SSHLauncher$2.call(SSHLauncher.java:696)
      	at java.util.concurrent.FutureTask.run(FutureTask.java:262)
      	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
      	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
      	at java.lang.Thread.run(Thread.java:745)
      [06/22/15 14:49:06] Launch failed - cleaning up connection
      [06/22/15 14:49:06] [SSH] Connection closed.

      On our slaves we would like to have hmac-sha2-512 / hmac-sha2-256 but that is not supported by Trilead SSH.


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              • Assignee:
                mc1arke Michael Clarke
                emma Emma Laurijssens
              • Votes:
                13 Vote for this issue
                21 Start watching this issue


                • Created: