Closed iameskild closed 4 days ago
Thanks for taking the time to write such a thorough RFD @iameskild Thoughts below:
To make it easier for Nebari admins, I propose we add a new CLI command,
nebari secret
I have no objection here - though since this will be a wrapper around some other CLIs, we need to make sure our docs cover in-depth documentation to also complete this without having to use our CLI (because some folks are pretty cautious, especially around access and security)
This command would call the cloud provider API and generate the necessary KMS. In the process, this command could also generate the .sops.yaml configuration file
It seems reasonable to me; we would need to decide on what that .sops.yaml
will look like (i.e. key/values and sane defaults)
Including secrets in the KubeSpawner's c.extra_pod_config) (in 03-profiles.py) will allow us to mount those secrets to the JupyterLab's user pod, thereby making them useable by the people. How these secrets are configured on the pod (as a file, env var, etc.), and which Keycloak groups have access to these secrests (if we want to add some basic "role-based access"), can be configured in the nebari-config.yaml.
This makes sense and would help with access to external data sources or other resources.
To ensure I am aligned with your proposal, the idea would be that any secret can be made available to specific roles
in keycloak thus, to all those users within those groups.
But at the same time, the users would not be able to say delete/modify the secrets themselves.
In such a case, it would be best to have these as some sort of env
variable.
That would be to create the Kubernetes secret from the encrypted file directly and then have the users decrypt the secret in their JupyterLab pod
-1
on this as it introduces another workflow/tool that the end-users have to deal with/familiarise. I prefer abstracting this as much as possible on the backend side to minimise end-user overhead.
Given that SOPS is a GitOps tool, it's important to ensure that admins don't accidentally commit plain text secret files in their repos. Adding more strict filters in the .gitignore will help a little but there's always a chance for mistakes.
We must do our due diligence, provide in-depth documentation, and suggest best practices.
Since this has been open for a while I am moving this RFD towards decision/voting. We are using a consent decision-making process for RFD approval therefore:
cc @nebari-dev/maintainers
@trallard I should have raised this earlier but didn't get to try out sops until around 5 days ago. I've looked at the encryption methods in sops and the most likely one we would push on our users is age. Because Age is the only one that supports ssh keys. Age supports ssh and pub/private keys. However sops does not support multiple keys with age (see https://github.com/mozilla/sops/issues/1078).
From a user usability perspective age with ssh IMO is the way to go. We cannot expect our users to create gpg keys, nor cloud keys. I see the following workflow:
nebari init
..... which github users would you like access to secrets?
https://github.com/<username>.keys
and adds to an age recipients fileage -d <filename>
and can optionally supply -i <path-to-ssh-github-key>
.Why can we not just directly use age? The key benefit I see is that we can specify a recipients file with multiple keys and can add/remove users from access to the secrets.
To my knowledge sops does not support this workflow. The one thing we would lose with age is that it encrypts the entire file (which to me personally I've never understood encrypting only the keys).
User Story 1:
I'm a software engineer doing client work. I have ever-changing client credentials to various web services (most notably s3 and gcs). I am looking for a more secure way to store my creds rather than in an .env
file on my machine/pod/NFS mount. I want to be assured that no one else can access these secrets. I shouldn't need to redeploy the entire nebari platform to set my secret. I shouldn't need a platform admin to set up my secrets.
User Story 2: I want to use Argo for my workflows, but the only to pass anything out of Argo is to store credentials - either in the workflow pod as env vars or in the docker image. Neither one is an effective long-term solution. When the creds are stored as env vars, they are visible to anyone who inspects the pod spec via k9s. One argument may be that whoever has access to the pod spec would also have access to the k8s secrets (one of the suggested solutions). There are some nuances here that others may need to expand on (@costrouc @Adam-D-Lewis) .
I'm cleaning up the RFD's and I'm going to close this for now due to no activity, but feel free to re-open if needed!
Summary
See relevant discussion:
Design Proposal
SOPS is a command-line tool for encrypting and decrypting secrets on your local machine.
In the context of Nebari, SOPS can potentially solve the following high-level issues:
Workflow
Starting point: a Nebari admin has a new secret some of their users may need (such as credentials for external data source). They have the appropriate cloud credentials available.
Handling secrets locally
Item 1. and 2. from the workflow outlined above can be performed directly using the cloud provider CLI (
aws kms create-key
) and the SOPS CLI (sops --encrypt <file>
).To make it easier for Nebari admins, I propose we add a new CLI command,
nebari secret
to handle items 1. and 2. This might look something like:.sops.yaml
configuration file to store the KMS andcreation_rules
.encrypt
command encrypts the secret and stores the encrypted secret in the designated location in the repo (./secrets.yaml
).decrypt
command decrypts the secret and prints it stdout.Include these secrets in the Nebari cluster
Items 3. and 4. from the workflow outlined above refers to how to get these secrets included in the Nebari cluster so that they can be used by those who need them.
There exists this SOPS terraform provider which can decrypt these encrypted secrets during the deployment. To grab these secrets and use them, we can create a
secrets
module instage/07-kubernetes-services
that returns the output (i.e. secret) that can be used to createkubernetes_secrets
as such:secret.yaml
:output "my-password" { value = data.sops_file.demo-secret.data["password"] sensitive = true }
resource "kubernetes_secret" "k8s-secret" { metadata { name = "sops-demo-secret" } data = { username = module.sops.my-password } }
c.extra_pod_config = {
as environment variables
}
secrets:
To accomplish this, we will need to add another callable that is used in the `c.kube_spawner_overrides in 03-profile.py:render_profiles.
Alternatives or approaches considered (if any)
There are many specifics that can be modified, such as how users are granted access or how the secrets that are consumed by the deployment.
As for a different usage of SOPS, I can think of one more. That would be to create the kubernetes secret from the encrypted file directly and then have the users decrypt the secret in their JupyterLab pod. This would eliminate the need for the
sops-terraform-provider
above.It might be possible to create tiered- secret files that are then associated to the keycloak groups again. This would introduce multiple KMS-keys.
The question that's hard to answer then becomes how to safely and conveniently disperse the KMS key to those who need to access the secrets.
Best practices
User impact
Access to secrets they may need to access job specific resources.
Unresolved questions
Given that SOPS is a GitOps tool, it's important to ensure that admins don't accidentally commit plain text secret files in their repos. Adding more strict filters in the
.gitignore
will help a little but there's always a chance for mistakes.