At a high level, it switches us to a distroless base container image, but that also includes several related bits:
- Add a writable /tmp but make the rest of our filesystems read-only at runtime.
- Condense our main server binaries into a single pinniped-server binary. This saves a bunch of space in
the image due to duplicated library code. The correct behavior is dispatched based on `os.Args[0]`, and
the `pinniped-server` binary is symlinked to `pinniped-concierge` and `pinniped-supervisor`.
- Strip debug symbols from our binaries. These aren't really useful in a distroless image anyway and all the
normal stuff you'd expect to work, such as stack traces, still does.
- Add a separate `pinniped-concierge-kube-cert-agent` binary with "sleep" and "print" functionality instead of
using builtin /bin/sleep and /bin/cat for the kube-cert-agent. This is split from the main server binary
because the loading/init time of the main server binary was too large for the tiny resource footprint we
established in our kube-cert-agent PodSpec. Using a separate binary eliminates this issue and the extra
binary adds only around 1.5MiB of image size.
- Switch the kube-cert-agent code to use a JSON `{"tls.crt": "<b64 cert>", "tls.key": "<b64 key>"}` format.
This is more robust to unexpected input formatting than the old code, which simply concatenated the files
with some extra newlines and split on whitespace.
- Update integration tests that made now-invalid assumptions about the `pinniped-server` image.
Signed-off-by: Matt Moyer <moyerm@vmware.com>
This CredentialIssuer field is called `spec.impersonationProxy.service.type`, not `spec.impersonationProxy.service.mode`.
Signed-off-by: Matt Moyer <moyerm@vmware.com>
This change updates the impersonation proxy code to run as a
distinct service account that only has permission to impersonate
identities. Thus any future vulnerability that causes the
impersonation headers to be dropped will fail closed instead of
escalating to the concierge's default service account which has
significantly more permissions.
Signed-off-by: Monis Khan <mok@vmware.com>
This typo wasn't caught in testing because 1) the Kubernetes API ignores the unknown field and 2) the `type` field defaults to `LoadBalancer` anyway, so things behave as expected.
Even though this doesn't cause any large problems, it's quite confusing.
Signed-off-by: Matt Moyer <moyerm@vmware.com>
Previously, our controllers would automatically create a CredentialIssuer with a singleton name. The helpers we had for this also used "raw" client access and did not take advantage of the informer cache pattern.
With this change, the CredentialIssuer is always created at install time in the ytt YAML. The controllers now only update the existing CredentialIssuer status, and they do so using the informer cache as much as possible.
This change is targeted at only the kubecertagent controller to start. The impersonatorconfig controller will be updated in a following PR along with other changes.
Signed-off-by: Matt Moyer <moyerm@vmware.com>
Update to follow https://golang.org/doc/effective_go#commentary:
> The first sentence should be a one-sentence summary that starts with the name being declared.
Signed-off-by: Matt Moyer <moyerm@vmware.com>
Followup on the previous comment to split apart the ServiceAccount of the kube-cert-agent and the main concierge pod. This is a bit cleaner and ensures that in testing our main Concierge pod never requires any privileged permissions.
Signed-off-by: Matt Moyer <moyerm@vmware.com>
Since 0dfb3e95c5, we no longer directly create the kube-cert-agent Pod, so our "use"
permission on PodSecurityPolicies no longer has the intended effect. Since the deployments controller is now the
one creating pods for us, we need to get the permission on the PodSpec of the target pod instead, which we do somewhat
simply by using the same service account as the main Concierge pods.
We still set `automountServiceAccountToken: false`, so this should not actually give any useful permissions to the
agent pod when running.
Signed-off-by: Matt Moyer <moyerm@vmware.com>
This controller is responsible for cleaning up kube-cert-agent pods that were deployed by previous versions.
They are easily identified because they use a different `kube-cert-agent.pinniped.dev` label compared to the new agent pods (`true` vs. `v2`).
Signed-off-by: Matt Moyer <moyerm@vmware.com>
This is a relatively large rewrite of much of the kube-cert-agent controllers. Instead of managing raw Pod objects, they now create a single Deployment and let the builtin k8s controller handle it from there.
This reduces the amount of code we need and should handle a number of edge cases better, especially those where a Pod becomes "wedged" and needs to be recreated.
Signed-off-by: Matt Moyer <moyerm@vmware.com>
To make an impersonation request, first make a TokenCredentialRequest
to get a certificate. That cert will either be issued by the Kube
API server's CA or by a new CA specific to the impersonator. Either
way, you can then make a request to the impersonator and present
that client cert for auth and the impersonator will accept it and
make the impesonation call on your behalf.
The impersonator http handler now borrows some Kube library code
to handle request processing. This will allow us to more closely
mimic the behavior of a real API server, e.g. the client cert
auth will work exactly like the real API server.
Signed-off-by: Monis Khan <mok@vmware.com>
This is more than an automatic merge. It also includes a rewrite of the CredentialIssuer API impersonation proxy fields using the new structure, and updates to the CLI to account for that new API.
Signed-off-by: Matt Moyer <moyerm@vmware.com>
This change adds a new virtual aggregated API that can be used by
any user to echo back who they are currently authenticated as. This
has general utility to end users and can be used in tests to
validate if authentication was successful.
Signed-off-by: Monis Khan <mok@vmware.com>
- Because the impersonation proxy config controller needs to be able
to delete the load balancer which it created
Signed-off-by: Margo Crawford <margaretc@vmware.com>
- Watch a configmap to read the configuration of the impersonation
proxy and reconcile it.
- Implements "auto" mode by querying the API for control plane nodes.
- WIP: does not create a load balancer or proper TLS certificates yet.
Those will come in future commits.
Signed-off-by: Margo Crawford <margaretc@vmware.com>
As of upgrading to Kubernetes 1.20, our aggregated API server nows runs some
controllers for the two flowcontrol.apiserver.k8s.io resources in the title of
this commit, so it needs RBAC to read them.
This should get rid of the following error messages in our Concierge logs:
Failed to watch *v1beta1.FlowSchema: failed to list *v1beta1.FlowSchema: flowschemas.flowcontrol.apiserver.k8s.io is forbidden: User "system:serviceaccount:concierge:concierge" cannot list resource "flowschemas" in API group "flowcontrol.apiserver.k8s.io" at the cluster scope
Failed to watch *v1beta1.PriorityLevelConfiguration: failed to list *v1beta1.PriorityLevelConfiguration: prioritylevelconfigurations.flowcontrol.apiserver.k8s.io is forbidden: User "system:serviceaccount:concierge:concierge" cannot list resource "prioritylevelconfigurations" in API group "flowcontrol.apiserver.k8s.io" at the cluster scope
Signed-off-by: Andrew Keesler <akeesler@vmware.com>
We have these redirects set up to make the `kubectl apply -f [...]` commands cleaner, but we never went back and fixed up the documentation to use them until now.
Signed-off-by: Matt Moyer <moyerm@vmware.com>
