Services can have some of their string fields interpolated. The new Workload
Identity flow doesn't interpolate the services before requesting signed
identities or using those identities to get Consul tokens.
Add support for interpolation to the WID manager and the Consul tokens hook by
providing both with a taskenv builder. Add an "interpolate workload" field to
the WI handle to allow passing the original workload name to the server so the
server can find the correct service to sign.
This changeset also makes two related test improvements:
* Remove the mock WID manager, which was only used in the Consul hook tests and
isn't necessary so long as we provide the real WID manager with the mock
signer and never call `Run` on it. It wasn't feasible to exercise the correct
behavior without this refactor, as the mocks were bypassing the new code.
* Fixed swapped expect-vs-actual assertions on the `consul_hook` tests.
Fixes: https://github.com/hashicorp/nomad/issues/20025
The allocrunner's `identity_hook` implements the interface for TaskStop, but
this interface is only ever called for task-level hooks. This results in a
leaked goroutine that tries to periodically renew WIs until the client shuts
down gracefully.
Add an implementation for the allocrunner's `PreKill` and `Destroy` hooks, so
that whenever an allocation is stopped or garbage collected we stop renewing its
Workload Identities. This also requires making the `Shutdown` method of `WIDMgr`
safe to call multiple times.
Includes changes to WID Manager that make it request signed identities for
services, as well as a few improvements to WIHandle introduced in #18672.
---------
Co-authored-by: Piotr Kazmierczak <470696+pkazmierczak@users.noreply.github.com>
When clients are restarted and the identity hook runs when we restore
allocations, the running allocations are likely to have already-signed Workload
Identities that are unexpired. Save these to the client's local state DB so that
we can avoid a thundering herd of RPCs during client restart. When we restore,
we'll check if there's at least one expired signed WI before making any initial
signing request.
Included:
* Renames `getIdentities` to `getInitialIdentities` to make the workflow more clear.
* Renames the existing `widmgr_test.go` file of integration tests, which is in its
own package to avoid circular imports to `widmgr_int_test.go`
Any code that tracks workloads and their identities should not rely on string
comparisons, especially since we support 2 types of workload identities: those
that identify tasks and those that identify services. This means we cannot rely
on task.Name for workload-identity pairs.
The new type structs.WIHandle solves this problem by providing a uniform way of
identifying workloads and their identities.
This PR introduces a new allocrunner-level consul_hook which iterates over
services and tasks, if their provider is consul, fetches consul tokens for all of
them, stores them in AllocHookResources and in task secret dirs.
Ref: hashicorp/team-nomad#404
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Co-authored-by: Tim Gross <tgross@hashicorp.com>
Since the identity_hook is meant to be the central place that makes signed
identities available to other hooks, it should also expose the default identity
that is signed by the plan applier.
Ref: hashicorp/team-nomad#404
This commit splits identity_hook between the allocrunner and taskrunner. The
allocrunner-level part of the hook signs each task identity, and the
taskrunner-level part picks it up and stores secrets for each task.
The code revamps the WIDMgr, which is now split into 2 interfaces:
IdentityManager which manages renewals of signatures and handles sending
updates to subscribers via Watch method, and IdentitySigner which only does the
signing.
This work is necessary for having a unified Consul login workflow that comes
with the new Consul integration. A new, allocrunner-level consul_hook will now
be the only hook doing Consul authentication.
Allows for multiple `identity{}` blocks for tasks along with user-specified audiences. This is a building block to allow workload identities to be used with Consul, Vault and 3rd party JWT based auth methods.
Expiration is still unimplemented and is necessary for JWTs to be used securely, so that's up next.
---------
Co-authored-by: Tim Gross <tgross@hashicorp.com>
