## Other Reference

The framework for this implementation of the CNI plugin is based on the
[containernetworking sample plugin](https://github.com/containernetworking/plugins/tree/main/plugins/sample)

The details for the deployment & installation of this plugin were pretty much lifted directly from the
[Calico CNI plugin](https://github.com/projectcalico/cni-plugin).

Specifically:

// See the License for the specific language governing permissions and
// limitations under the License.

// This is a sample chained plugin that supports multiple CNI versions. It
// parses prevResult according to the cniVersion
package plugin

import (
	"fmt"

	"github.com/containernetworking/plugins/pkg/ns"

	"istio.io/istio/pkg/log"
	"istio.io/istio/tools/istio-iptables/pkg/cmd"
	"istio.io/istio/tools/istio-iptables/pkg/config"

// - this is because during add specifically, if CNI plugins have not finished executing,
// K8S may get a pod Add event without any IPs in the object, and the pod will later be updated with IPs.
//
// We always need the IPs, but this is fine because this AddPodToMesh can be called from the CNI plugin as well,

  //
  // IfNeeded: the webhook will be called at least one additional time as part of the admission evaluation
  // if the object being admitted is modified by other admission plugins after the initial webhook call.
  // Webhooks that specify this option *must* be idempotent, able to process objects they previously admitted.
  // Note:

  //
  // IfNeeded: the webhook will be called at least one additional time as part of the admission evaluation
  // if the object being admitted is modified by other admission plugins after the initial webhook call.
  // Webhooks that specify this option *must* be idempotent, able to process objects they previously admitted.
  // Note:

	// Name of the CNI config file
	CNIConfName string
	// Whether to install CNI plugin as a chained or standalone
	ChainedCNIPlugin bool

	// CNI config template file
	CNINetworkConfigFile string
	// CNI config template string
	CNINetworkConfig string

	// Logging level
	LogLevel string
	// Name of the kubeconfig file used by the CNI plugin
	KubeconfigFilename string
	// The file mode to set when creating the kubeconfig file

# This will build the final image based on either debug or distroless from above
# hadolint ignore=DL3006
FROM ${BASE_DISTRIBUTION:-debug}

LABEL description="Istio CNI plugin installer."

ARG TARGETARCH
COPY ${TARGETARCH:-amd64}/istio-cni /opt/cni/bin/istio-cni
COPY ${TARGETARCH:-amd64}/install-cni /usr/local/bin/install-cni

  optional k8s.io.api.authentication.v1.UserInfo userInfo = 1;
}

// TokenReview attempts to authenticate a token to a known user.
// Note: TokenReview requests may be cached by the webhook token authenticator
// plugin in the kube-apiserver.
message TokenReview {
  // Standard object's metadata.
  // More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata
  // +optional

              WebAssembly filters. See more details at: https://istio.io/docs/reference/config/proxy_extensions/wasm-plugin.html'
            properties:
              failStrategy:
                description: |-
                  Specifies the failure behavior for the plugin due to fatal errors.

                  Valid Options: FAIL_CLOSE, FAIL_OPEN
                enum:
                - FAIL_CLOSE

			// We need a pod IP - if the pod was added via the CNI plugin, that plugin told us the IPs
			// for the pod. If this is a pod added via informer, the pod should have already gone thru
			// the CNI plugin chain, and have a PodIP.
			//
			// If PodIPs exists, it is preferred, otherwise fallback to PodIP.
			//
			// If we get to this point and have a pod that really and truly has no IP in either of those,