The value here is that the exec plugin author can use the kubeconfig to assert
how standard input is treated with respect to the exec plugin, e.g.,
- an exec plugin author can ensure that kubectl fails if it cannot provide
standard input to an exec plugin that needs it (Always)
- an exec plugin author can ensure that an client-go process will still call an
exec plugin that prefers standard input even if standard input is not
available (IfAvailable)
Signed-off-by: Andrew Keesler <akeesler@vmware.com>
Kubernetes-commit: cd83d89ac94c5b61fdd38840098e7223e5af0d34
If a user specifies basic auth, then apply the same short circuit logic
that we do for bearer tokens (see comment).
Signed-off-by: Andrew Keesler <akeesler@vmware.com>
Kubernetes-commit: 9dee2b95c27a9d61c2bade8fe67f120b5853c4d6
- The main idea here is that we want to 1) prevent potentially large CA
bundles from being set in an exec plugin's environment and 2) ensure
that the exec plugin is getting everything it needs in order to talk to
a cluster.
- Avoid breaking existing manual declarations of rest.Config instances by
moving exec Cluster to kubeconfig internal type.
- Use client.authentication.k8s.io/exec to qualify exec cluster extension.
- Deep copy the exec Cluster.Config when we copy a rest.Config.
Signed-off-by: Andrew Keesler <akeesler@vmware.com>
Kubernetes-commit: c4299d15d5289768808034676858e76a177eeae5
If a bearer token is present in a request, the exec credential plugin should accept that as the chosen method of authentication. Judging by an [earlier comment in exec.go](c18bc7e9f7/staging/src/k8s.io/client-go/plugin/pkg/client/auth/exec/exec.go (L217)), this was already intended. This would however not work since UpdateTransportConfig would set the GetCert callback which would then get called by the transport, triggering the exec plugin action even with a token present in the request. See linked issue for further details.
See #87369 for further details.
Signed-off-by: Anders Eknert <anders.eknert@bisnode.com>
Kubernetes-commit: b423216a3b781009fb4ec4d5974eeb3f882f9d2d
This commit adds the ability for users to specify an install hint for
their exec credential provider binary.
In the exec credential provider workflow, if the exec credential binary
does not exist, then the user will see some sort of ugly
exec: exec: "does-not-exist": executable file not found in $PATH
error message. If some user downloads a kubeconfig from somewhere, they
may not know that kubectl is trying to use a binary to obtain
credentials to auth to the API, and scratch their head when they see
this error message. Furthermore, even if a user does know that their
kubeconfig is trying to run a binary, they might not know how to obtain
the binary. This install hint seeks to ease the above 2 user pains.
Signed-off-by: Andrew Keesler <akeesler@vmware.com>
Kubernetes-commit: 94e2065df2eef3b198942efb156ef6e27abcc6f9