9702c6e6e9
This commit adds support for using `gke-exec-auth-plugin` (vTPM-based
certificates for mTLS) for webhooks when calling endpoints matching
`*.googleapis.com`, and integrates this support with
ValidatingAdmissionWebhook.
To enable it, request ValidatingAdmissionWebhook with
`ADMISSION_CONTROL=...,ValidatingAdmissionWebhook,...` (default) and
opt in to `gke-exec-auth-plugin` using `WEBHOOK_GKE_EXEC_AUTH=true`
during the configuration process.
If you don't opt-in, ValidatingAdmissionWebhook will be deployed as
before.
Requesting `WEBHOOK_GKE_EXEC_AUTH=true` will fail if you have not
provided other configuration variables:
* `EXEC_AUTH_PLUGIN_URL`: controls whether `gke-exec-auth-plugin` is
downloaded during the installation step. A prerequisite for
actually using the plugin.
* `TOKEN_URL`, `TOKEN_BODY`, and `TOKEN_BODY_UNQUOTED`:
configuration values used when calling the plugin. `TOKEN_URL`
and `TOKEN_BODY` have existing usage. `TOKEN_BODY_UNQUOTED` is a
new variable that is meant to sidestep the problem of inverting
`strconv.Quote` in Bash.
The existing configuration process for ImagePolicyWebhook has been
reworked to make it play nicely with ValidatingAdmissionWebhook under
`WEBHOOK_GKE_EXEC_AUTH=true`.
* It originally placed the ImagePolicyWebhook configuration object
at the top-level of the file specified by
`--admission-control-config-file`. I can't see why this worked;
it must have been hitting some sort of lucky path through the
various config file loading mechanisms. Now, it places its
configuration in a sub-field of that file, which is shared among
all admission control plugins.
* It mounted its various config files read-write. I reviewed the
code and couldn't see why it was necessary, so I moved the config
files into the existing read-only mount at `/etc/srv/kubernetes`.
* It now checks that all the configuration values it requires have
been provided.
Co-authored-by: Mike Danese <mikedanese@google.com>
Co-authored-by: Taahir Ahmed <taahm@google.com>
Cluster Configuration
Deprecation Notice: This directory has entered maintenance mode and will not be accepting new providers. Deployments in this directory will continue to be maintained and supported at their current level of support.
The scripts and data in this directory automate creation and configuration of a Kubernetes cluster, including networking, DNS, nodes, and control plane components.
See the getting-started guides for examples of how to use the scripts.
cloudprovider/config-default.sh contains a set of tweakable definitions/parameters for the cluster.