Merge pull request #60590 from immutableT/enc_config_automation

Automatic merge from submit-queue (batch tested with PRs 60420, 60590). If you want to cherry-pick this change to another branch, please follow the instructions <a href="https://github.com/kubernetes/community/blob/master/contributors/devel/cherry-picks.md">here</a>.

Enable AESGCM encryption of secrets in etcd by default.

**What this PR does / why we need it**:
Enable encryption of secrets in etcd via AESGCM transform (as described here https://kubernetes.io/docs/tasks/administer-cluster/encrypt-data/) during kube-up.sh build of a cluster.
**Which issue(s) this PR fixes** *(optional, in `fixes #<issue number>(, fixes #<issue_number>, ...)` format, will close the issue(s) when PR gets merged)*:
Fixes #

**Special notes for your reviewer**:

**Release note**:

```release-note
NONE
```

cluster/gce/config-default.sh

@@ -194,6 +194,25 @@ if [[ ${ENABLE_METADATA_CONCEALMENT:-} == "true" ]]; then
   PROVIDER_VARS="${PROVIDER_VARS:-} ENABLE_METADATA_CONCEALMENT METADATA_CONCEALMENT_NO_FIREWALL"
 fi
 
+
+# Enable AESGCM encryption of secrets by default.
+ENCRYPTION_PROVIDER_CONFIG="${ENCRYPTION_PROVIDER_CONFIG:-}"
+if [[ -z "${ENCRYPTION_PROVIDER_CONFIG}" ]]; then
+    ENCRYPTION_PROVIDER_CONFIG=$(cat << EOM | base64 | tr -d '\r\n'
+kind: EncryptionConfig
+apiVersion: v1
+resources:
+  - resources:
+    - secrets
+    providers:
+    - aesgcm:
+        keys:
+        - name: key1
+          secret: $(dd if=/dev/random bs=32 count=1 status=none | base64 | tr -d '\r\n')
+EOM
+)
+fi
+
 # Optional: Enable node logging.
 ENABLE_NODE_LOGGING="${KUBE_ENABLE_NODE_LOGGING:-true}"
 LOGGING_DESTINATION="${KUBE_LOGGING_DESTINATION:-gcp}" # options: elasticsearch, gcp

cluster/gce/util.sh

@@ -841,6 +841,7 @@ ETCD_CA_KEY: $(yaml-quote ${ETCD_CA_KEY_BASE64:-})
 ETCD_CA_CERT: $(yaml-quote ${ETCD_CA_CERT_BASE64:-})
 ETCD_PEER_KEY: $(yaml-quote ${ETCD_PEER_KEY_BASE64:-})
 ETCD_PEER_CERT: $(yaml-quote ${ETCD_PEER_CERT_BASE64:-})
+ENCRYPTION_PROVIDER_CONFIG: $(yaml-quote ${ENCRYPTION_PROVIDER_CONFIG:-})
 EOF
     if [[ "${ENABLE_TOKENREQUEST:-}" == "true" ]]; then
       cat >>$file <<EOF