openssh
Install and configure an openssh server.
Table of Contents
General notes
See the full SaltStack Formulas installation and usage instructions.
If you are interested in writing or contributing to formulas, please pay attention to the Writing Formula Section.
If you want to use this formula, please pay attention to the FORMULA
file and/or git tag
,
which contains the currently released version. This formula is versioned according to Semantic Versioning.
See Formula Versioning Section for more details.
Contributing to this repo
Commit message formatting is significant!!
Please see :ref:`How to contribute <CONTRIBUTING>` for more details.
Available states
openssh
Installs the openssh
server package and service.
openssh.auth
Manages SSH certificates for users.
openssh.auth_map
Same functionality as openssh.auth but with a simplified Pillar syntax. Plays nicely with Pillarstack.
openssh.banner
Installs a banner that users see when SSH-ing in.
openssh.client
Installs the openssh client package.
openssh.config
Installs the ssh daemon configuration file included in this formula
(under "openssh/files"). This configuration file is populated
by values from pillar. pillar.example
results in the generation
of the default sshd_config
file on Debian Wheezy.
It is highly recommended PermitRootLogin
is added to pillar
so root login will be disabled.
openssh.config_ini
Version of managing sshd_config
that uses the
ini_managed.option_present
state module, so it enables to override only one or
multiple values and keeping the defaults shipped by your
distribution.
openssh.known_hosts
Manages /etc/ssh/ssh_known_hosts
and fills it with the
public SSH host keys of your minions (collected via the Salt mine)
and of hosts listed in you pillar data. It's possible to include
minions managed via salt-ssh
by using the known_hosts_salt_ssh
renderer.
You can restrict the set of minions
whose keys are listed by using the pillar data openssh:known_hosts:target
and openssh:known_hosts:tgt_type
(those fields map directly to the
corresponding attributes of the mine.get
function).
The Salt mine is used to share the public SSH host keys, you must thus
configure it accordingly on all hosts that must export their keys. Two
mine functions are required, one that exports the keys (one key per line,
as they are stored in /etc/ssh/ssh_host_*_key.pub
) and one that defines
the public hostname that the keys are associated to. Here's the way to
setup those functions through pillar:
# Required for openssh.known_hosts mine_functions: public_ssh_host_keys: mine_function: cmd.run cmd: cat /etc/ssh/ssh_host_*_key.pub python_shell: True public_ssh_hostname: mine_function: grains.get key: id
The above example assumes that the minion identifier is a valid DNS name
that can be used to connect to the host. If that's not the case, you might
want to use the fqdn
grain instead of the id
one. The above example
also uses the default mine function names used by this formula. If you have to
use other names, then you should indicate the names to use in pillar keys
openssh:known_hosts:mine_keys_function
and
openssh:known_hosts:mine_hostname_function
.
You can also integrate alternate DNS names of the various hosts in
/etc/ssh/ssh_known_hosts
. You just have to specify all the alternate DNS names as a
list in the openssh:known_hosts:aliases
pillar key. Whenever the IPv4 or
IPv6 behind one of those DNS entries matches an IPv4 or IPv6 behind the
official hostname of a minion, the alternate DNS name will be associated to the
minion's public SSH host key.
To include minions managed via salt-ssh install the known_hosts_salt_ssh
renderer:
# in pillar.top: '*': - openssh.known_hosts_salt_ssh # In your salt/ directory: # Link the pillar file: mkdir pillar/openssh ln -s ../../formulas/openssh-formula/_pillar/known_hosts_salt_ssh.sls pillar/openssh/known_hosts_salt_ssh.sls
You'll find the cached pubkeys in Pillar openssh:known_hosts:salt_ssh
.
It's possible to define aliases for certain hosts:
openssh: known_hosts: cache: public_ssh_host_names: minion.id: - minion.id - alias.of.minion.id
The cache is populated by applying openssh.gather_host_keys
to the salt master:
salt 'salt-master.example.test' state.apply openssh.gather_host_keys
The state tries to fetch the SSH host keys via salt-ssh
. It calls the command as user
salt-master
by default. The username can be changed via Pillar:
openssh: known_hosts: cache: user: salt-master
Use a cronjob to populate a host key cache:
# crontab -e -u salt-master 0 1 * * * salt 'salt-master.example.test' state.apply openssh.gather_host_keys
If you must have the latest pubkeys, run the state before all others:
# states/top.sls: base: salt: # slooooow! - openssh.gather_host_keys
You can also use a "golden" known hosts file. It overrides the keys fetched by the cronjob. This lets you re-use the trust estabished in the salt-ssh user's known_hosts file:
# In your salt/ directory: (Pillar expects the file here.) ln -s /home/salt-master/.ssh/known_hosts ./known_hosts # Test it: salt-ssh 'minion' pillar.get 'openssh:known_hosts:salt_ssh'
To add public keys of hosts not among your minions list them under the
pillar key openssh:known_hosts:static
:
openssh: known_hosts: static: github.com: 'ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAq[...]' gitlab.com: 'ssh-rsa AAAAB3NzaC1yc2EAAAADAQABAAABA[...]'
Pillar openssh:known_hosts:static
overrides openssh:known_hosts:salt_ssh
.
To include localhost and local IP addresses (127.0.0.1
and ::1
) use this Pillar:
openssh: known_hosts: include_localhost: True
openssh.moduli
Manages the system wide /etc/ssh/moduli
file.
Testing
Linux testing is done with kitchen-salt
.
Requirements
- Ruby
- Docker
$ gem install bundler
$ bundle install
$ bin/kitchen test [platform]
Where [platform]
is the platform name defined in kitchen.yml
,
e.g. debian-9-2019-2-py3
.
bin/kitchen converge
Creates the docker instance and runs the template
main state, ready for testing.
bin/kitchen verify
Runs the inspec
tests on the actual instance.
bin/kitchen destroy
Removes the docker instance.
bin/kitchen test
Runs all of the stages above in one go: i.e. destroy
+ converge
+ verify
+ destroy
.
bin/kitchen login
Gives you SSH access to the instance for manual testing.