package http

import (
	"context"
	"net"
	"time"
)

// CheckPortAvailability - check if given host and port is already in use.
// Note: The check method tries to listen on given port and closes it.
// It is possible to have a disconnected client in this tiny window of time.
func CheckPortAvailability(host, port string, opts TCPOptions) (err error) {
	lc := &net.ListenConfig{}

-A OUTPUT -p udp --dport 53 -m owner --uid-owner 1337 -j CT --zone 1
-A OUTPUT -p udp --sport 15053 -m owner --uid-owner 1337 -j CT --zone 2
-A OUTPUT -p udp --dport 53 -m owner --gid-owner 1337 -j CT --zone 1
-A OUTPUT -p udp --sport 15053 -m owner --gid-owner 1337 -j CT --zone 2
-A OUTPUT -p udp --dport 53 -j CT --zone 2
-A PREROUTING -p udp --sport 53 -j CT --zone 1

	}
	sort.Slice(endpoints, func(i, j int) bool {
		iDirection, iSubset, iName, iPort := safelyParseSubsetKey(endpoints[i].ClusterName)
		jDirection, jSubset, jName, jPort := safelyParseSubsetKey(endpoints[j].ClusterName)
		if iName == jName {
			if iSubset == jSubset {
				if iPort == jPort {
					return iDirection < jDirection
				}
				return iPort < jPort
			}
			return iSubset < jSubset
		}
		return iName < jName
	})

		"http": 80,
	}

	for _, port := range ingress.service.Spec.Ports {
		if port.Protocol != "TCP" || !portsToShow[port.Name] {
			continue
		}

		// Get port number
		_, err := pilotcontroller.FindPort(ingress.pods[0], &port)
		if err == nil {
			nport := int(port.Port)
			protocol := string(configKube.ConvertProtocol(port.Port, port.Name, port.Protocol, port.AppProtocol))

iptables -t mangle -A ISTIO_PRERT -p tcp -m tcp --dport 15008 -m mark ! --mark 0x539/0xfff -j TPROXY --on-port 15008 --tproxy-mark 0x111/0xfff
iptables -t mangle -A ISTIO_PRERT -p tcp -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
iptables -t mangle -A ISTIO_PRERT ! -d 127.0.0.1/32 -p tcp -m mark ! --mark 0x539/0xfff -j TPROXY --on-port 15006 --tproxy-mark 0x111/0xfff

	)

	// CLI: -A ISTIO_OUTPUT ! -o lo -p udp -m udp --dport 53 -j REDIRECT --to-port 15053
	//
	// DESC: If this is a UDP DNS request to a non-localhost resolver, send it to ztunnel DNS proxy port
	if redirectDNS {
		iptablesBuilder.AppendRule(
			iptableslog.UndefinedCommand, ChainInpodOutput, iptablesconstants.NAT,
			"!", "-o", "lo",
			"-p", "udp",
			"-m", "udp",
			"--dport", "53",
			"-j", "REDIRECT",

iptables -t mangle -A ISTIO_PRERT -p tcp -m tcp --dport 15008 -m mark ! --mark 0x539/0xfff -j TPROXY --on-port 15008 --tproxy-mark 0x111/0xfff
iptables -t mangle -A ISTIO_PRERT -p tcp -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
iptables -t mangle -A ISTIO_PRERT ! -d 127.0.0.1/32 -p tcp -m mark ! --mark 0x539/0xfff -j TPROXY --on-port 15006 --tproxy-mark 0x111/0xfff

-A ISTIO_DIVERT -j ACCEPT
-A ISTIO_TPROXY ! -d 127.0.0.1/32 -p tcp -j TPROXY --tproxy-mark 1337/0xffffffff --on-port 15006
-A PREROUTING -p tcp -j ISTIO_INBOUND
-A ISTIO_INBOUND -p tcp --dport 15020 -j RETURN
-A ISTIO_INBOUND -p tcp --dport 15021 -j RETURN
-A ISTIO_INBOUND -p tcp --dport 15090 -j RETURN
-A ISTIO_INBOUND -p tcp -m conntrack --ctstate RELATED,ESTABLISHED -j ISTIO_DIVERT
-A ISTIO_INBOUND -p tcp -j ISTIO_TPROXY

-A ISTIO_DIVERT -j ACCEPT
-A ISTIO_TPROXY ! -d 127.0.0.1/32 -p tcp -j TPROXY --tproxy-mark 1337/0xffffffff --on-port 15006
-A PREROUTING -p tcp -j ISTIO_INBOUND
-A ISTIO_INBOUND -p tcp --dport 15020 -j RETURN
-A ISTIO_INBOUND -p tcp --dport 15021 -j RETURN
-A ISTIO_INBOUND -p tcp --dport 15090 -j RETURN
-A ISTIO_INBOUND -p tcp -m conntrack --ctstate RELATED,ESTABLISHED -j ISTIO_DIVERT
-A ISTIO_INBOUND -p tcp -j ISTIO_TPROXY

> NOTE: MinIO runs console on random port by default, if you wish to choose a specific port use `--console-address` to pick a specific interface and port.

### Things to consider