SSH Algorithm Management

SSH algorithms on the VOSS-4-UC platform can be viewed, enabled, disabled or reset to the default list.

The available commands are:

  • system ssh algorithm default - Reset enabled and disabled algorithms to their default.

  • system ssh algorithm list < all | algorithm-type > - Display all or any of <cipher|mac|kex|key> SSH algorithms. The list will also show enabled and disabled algorithm types.

  • system ssh algorithm disable <algorithm-type> <algorithm-name> - Disable algorithms of a specific type <cipher|mac|kex|key>, by specifying a space separated list of algorithm names.

    Note that not all algorithms can be disabled.

    For example, to disable two of the cipher algorithms, the command would be:

    system ssh algorithm disable cipher aes128-ctr aes192-ctr

  • system ssh algorithm enable <algorithm-type> <algorithm-name> - Enable algorithms of a specific type <cipher|mac|kex|key>, by specifying a space separated list of algorithm names.

Command example to view status of all algorithms types:

platform@VOSS:~$ system ssh algorithm list all
    cipher:
        enabled:
            aes128-ctr
            aes192-ctr
            aes256-ctr
    kex:
        enabled:
            diffie-hellman-group1-sha1
            diffie-hellman-group14-sha1
            diffie-hellman-group-exchange-sha1
            diffie-hellman-group-exchange-sha256
            curve25519-sha256@libssh.org
    key:
        enabled:
            ssh-ed25519
            ssh-ed25519-cert-v01@openssh.com
            ssh-rsa
            ssh-dss
            ecdsa-sha2-nistp256
            ecdsa-sha2-nistp384
            ecdsa-sha2-nistp521
            ssh-rsa-cert-v01@openssh.com
            ssh-dss-cert-v01@openssh.com
            ecdsa-sha2-nistp256-cert-v01@openssh.com
            ecdsa-sha2-nistp384-cert-v01@openssh.com
            ecdsa-sha2-nistp521-cert-v01@openssh.com
    mac:
        enabled:
            hmac-sha1
            hmac-sha2-256
            hmac-sha2-512
            hmac-ripemd160
            hmac-ripemd160@openssh.com
            umac-128@openssh.com
            hmac-sha1-etm@openssh.com
            hmac-sha2-256-etm@openssh.com
            hmac-sha2-512-etm@openssh.com
            hmac-ripemd160-etm@openssh.com
            umac-128-etm@openssh.com