GetCIDR (discovery/cidr.go)

Discovers Kubernetes Pod and Service CIDRs without creating probe pods for fast cluster connectivity.

// Source: https://github.com/kubenetworks/kubevpn | License: MIT | Copyright 2022 wencaiwulue
// Provided via justclaw.it.com; keep this notice with the code.
package discovery

import (
	"context"
	"fmt"
	"net"
	"strings"

	corev1 "k8s.io/api/core/v1"
	v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/util/sets"
	"k8s.io/client-go/kubernetes"
	typedcorev1 "k8s.io/client-go/kubernetes/typed/core/v1"

	plog "github.com/wencaiwulue/kubevpn/v2/pkg/log"
)

// GetCIDR discovers cluster Pod and Service CIDRs using pod-free strategies only:
// component flags in kube-system pods, the Service IP-range error trick, and inference from
// live Pod/Service IPs. It deliberately does NOT create a probe pod / exec (which added ~15s
// per connect) — trading some completeness on locked-

... (truncated -- full source via MCP)