// The time (in seconds) the connection needs to remain idle before
			// TCP starts sending keepalive probes
			_ = syscall.SetsockoptInt(fd, syscall.IPPROTO_TCP, syscall.TCP_KEEPIDLE, 15)

			// Number of probes.
			// ~ cat /proc/sys/net/ipv4/tcp_keepalive_probes (defaults to 9, we reduce it to 5)
			_ = syscall.SetsockoptInt(fd, syscall.IPPROTO_TCP, syscall.TCP_KEEPCNT, 5)

	DNSCapturePort              = 15053
	ZtunnelInboundPort          = 15008
	ZtunnelOutboundPort         = 15001
	ZtunnelInboundPlaintextPort = 15006
	ProbeIPSet                  = "istio-inpod-probes"

	RouteTableInbound    = 100

	DNSCapturePort              = 15053
	ZtunnelInboundPort          = 15008
	ZtunnelOutboundPort         = 15001
	ZtunnelInboundPlaintextPort = 15006
	ProbeIPSet                  = "istio-inpod-probes"
)

var log = istiolog.RegisterScope("iptables", "iptables helper")

type Config struct {
	RestoreFormat bool `json:"RESTORE_FORMAT"`
	TraceLogging  bool `json:"IPTABLES_TRACE_LOGGING"`

)

const (
	// to reliably identify kubelet healthprobes from inside the pod (versus standard kube-proxy traffic,
	// since the IP is normally the same), we SNAT identified host probes in the host netns to a fixed
	// APIPA/"link-local" IP.
	//
	// It doesn't matter what this IP is, so long as it's not routable and doesn't collide with anything else.
	//