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>
using `local -r` will blow up, example output:
```
/home/kubernetes/bin/configure.sh: line 388: local: manifest_name: readonly variable
```
Change-Id: Id379180803d44dd9c7ac0da41c1cd56de0fe54a4
Split arguments to be passed to cluster autoscaler binary,
so each argument is passed separately.
This is preparatory work for migrating CA to disroless base image
and passing multiple arguments together does not work if CA is
not wrapped around with shell script
Change-Id: I26b5a764d2a12079c7f4ed6633ccabf8d623e232
* Touched containers: kube-apiserver, kube-scheduler,
kube-controller-manager.
* Remove the shell dependencies when upstart the containers.
* Reformat the command parameters to ["Exec", "Param1", "Param2"]
