It includes the work over the state store, the PRC server, the HTTP server, the go API package and the CLI's command. To read more on the actuall functionality, refer to the RFCs [NMD-178] Locking with Nomad Variables and [NMD-179] Leader election using locking mechanism for the Autoscaler.
ACL policies can be associated with a job so that the job's Workload Identity
can have expanded access to other policy objects, including other
variables. Policies set on the variables the job automatically has access to
were ignored, but this includes policies with `deny` capabilities.
Additionally, when resolving claims for a workload identity without any attached
policies, the `ResolveClaims` method returned a `nil` ACL object, which is
treated similarly to a management token. While this was safe in Nomad 1.4.x,
when the workload identity token was exposed to the task via the `identity`
block, this allows a user with `submit-job` capabilities to escalate their
privileges.
We originally implemented automatic workload access to Variables as a separate
code path in the Variables RPC endpoint so that we don't have to generate
on-the-fly policies that blow up the ACL policy cache. This is fairly brittle
but also the behavior around wildcard paths in policies different from the rest
of our ACL polices, which is hard to reason about.
Add an `ACLClaim` parameter to the `AllowVariableOperation` method so that we
can push all this logic into the `acl` package and the behavior can be
consistent. This will allow a `deny` policy to override automatic access (and
probably speed up checks of non-automatic variable access).
* docs: clarify nomad vars vs vault
I think we should make the difference in root key management between
Nomad and Vault clear in the concept docs. I didn't see anywhere else in
the docs we compared it.
I also s/secrets/variables everywhere except the first sentence since
the feature is intended to be more generic than secrets. Right now it's
more of a compliment to Consul's kv than Vault due to root key handling
and featureset.
* Update website/content/docs/concepts/variables.mdx
Co-authored-by: Tim Gross <tgross@hashicorp.com>
