#!/bin/bash# SPDX-License-Identifier: GPL-2.0 NR_FILES=32768readonly NETNS="ns-$(mktemp -u XXXXXX)" # default valuesport=443addr_v6="2001:0db8:0:f101::1"addr_v4="10.8.8.8"use_v6=trueaddr="" usage() {    echo "Usage: $0 [-6 | -4] [-p port] [-a address]"    echo -e "\t6: use ipv6"    echo -e "\t4: use ipv4"    echo -e "\tport: Port number"    echo -e "\taddress: ip address"} while getopts "ha:p:64" opt; do    case ${opt} in	h)	    usage $0	    exit 0	    ;;	a)  addr=$OPTARG;;	p)	    port=$OPTARG;;	6)	    use_v6=true;;	4)	    use_v6=false;;    esacdone setup() {    ip netns add "${NETNS}"    ip -netns "${NETNS}" link add veth0 type veth peer name veth1    ip -netns "${NETNS}" link set lo up    ip -netns "${NETNS}" link set veth0 up    ip -netns "${NETNS}" link set veth1 up     if [[ "$use_v6" == true ]]; then        ip -netns "${NETNS}" addr add $addr_v6 nodad dev veth0    else        ip -netns "${NETNS}" addr add $addr_v4 dev lo    fi} cleanup() {    ip netns del "${NETNS}"} if [[ "$addr" != "" ]]; then    addr_v4=$addr;    addr_v6=$addr;fisetupif [[ "$use_v6" == true ]] ; then    ip netns exec "${NETNS}" sh -c \        "ulimit -n ${NR_FILES};./bind_bhash ${port} ipv6 ${addr_v6}"else    ip netns exec "${NETNS}" sh -c \        "ulimit -n ${NR_FILES};./bind_bhash ${port} ipv4 ${addr_v4}"ficleanup