Update Salt Master configuration template

[bastian-src]

• Add netapi_enable_clients explicitly due to 3006 changes https://docs.saltproject.io/en/master/topics/netapi/netapi-enable-clients.html#select-client-interfaces-to-enable

→ This is more of an pro-active change. I don't quite know where exactly we run into an issue with cherrypy-API permissions. So, I need a second opinion on this.

• Set user for running Salt Master service due to 3006 changes https://docs.saltproject.io/en/3006/topics/releases/3006.0.html#linux-packaging-salt-master-salt-user-and-group

→ This is motivated by the following change:

Since 3006, Salt installs with an explicit user that runs the Salt Master daemon in order to limit the daemon permissions. If that users differs from the user that we execute the salt ... commands with (when triggering Salt from Smart Proxy), we get some permission issues. More specifically, sudo -u foreman-proxy salt '*' test.ping runs into the following error:

[ERROR   ] Unable to connect to the salt master publisher at /var/run/salt/master
The salt master could not be contacted. Is master running?

When executing salt '*' test.ping, that comand wants to connect to the Salt Master whose PID is stored in /var/run/salt/master/*. But, with the 3006-explicit-user update, they limit access to the /var/run/salt folder to the same user which runs the Salt Master daemon.

Therefore, I see two options:

A) Make the Salt Master daemon run with the same user that we execute the salt ... commands with (currently implemented in this PR)
B) Take care that the foreman-proxy user has the necessary permissions/adapt the folder permissions that the foreman-proxy user can execute salt ... even if the daemon is started by a different user.

[ekohl]

I've often wondered if we shouldn't have code to fully manage the whole salt server, just like we can set up and manage the the configuration.

What I mean by that is to simplify the procedure. https://docs.theforeman.org/nightly/Managing_Configurations_Salt/index-katello.html now documents a lot of manual steps and that's generally not something we want.

For example, https://docs.theforeman.org/nightly/Managing_Configurations_Salt/index-katello.html#Authenticating_Salt_Minions_Using_Host_Names_managing-configurations-salt tells you to add foreman-proxy to the root group. IMHO that's extremely dangerous.

https://docs.theforeman.org/nightly/Managing_Configurations_Salt/index-katello.html#Configuring_the_Salt_API_managing-configurations-salt is also completely wrong because it must use installer options to persist.

I wrote up https://github.com/theforeman/puppet-foreman_proxy/blob/master/examples/salt.pp and https://github.com/theforeman/puppet-foreman_proxy/blob/master/spec/acceptance/salt_spec.rb as end-to-end testing, but as you can see it's still extremely basic. It would be nice if we actually had testing that verified some end-to-end workflow.

@maximiliankolb tagging you in because the Salt documentation must be reviewed. It can't be right.

[maximiliankolb]

Thanks for the ping. Making sure that the docs work after we've merged this is definitely on my plate!

@sbernhard Is there any use case to configure the interfaces? Or are these two simply required to make Salt+Foreman work?

docs: https://docs.saltproject.io/en/master/topics/netapi/netapi-enable-clients.html#enabling-netapi-client-interfaces

[maximiliankolb]

@sbernhard Friendly reminder.

[bastian-src]

Coming back to this, thanks @ekohl for the review and feedback!

I totally agree, we should re-think the user management and I think since Salt switches to a non-root user we can take this as reason to update ours too.

However, for this PR, I'd just update the master configuration. I'm currently testing which default config we should apply for netapi to guarantee that the salt-api works for Foreman.

[sbernhard]

LGTM

[bastian-src]

@ekohl I've rebased to latest master, I assume the failing Ubuntu tests are unrelated.

I'm addressing some of your concerns on how we should manage the salt service in my RFC: https://community.theforeman.org/t/rfc-running-salt-as-non-root-user/39820

From my side, this seems ready to be merged?