Share Wifi (or VPN tunnel) through eth

wifi2eth.sh

#!/bin/bash

# Share Wifi (or VPN tunnel) through eth

ip_address="192.168.2.1"
netmask="255.255.255.0"
dhcp_range_start="192.168.2.2"
dhcp_range_end="192.168.2.255"
dhcp_time="12h"
dns_server="1.1.1.1"
eth="eth0"
wlan="tun0" # share the vpn tunnel rather than wlan

sudo systemctl start network-online.target &> /dev/null

sudo iptables -F
sudo iptables -t nat -F
sudo iptables -t nat -A POSTROUTING -o $wlan -j MASQUERADE

sudo sh -c "echo 1 > /proc/sys/net/ipv4/ip_forward"

sudo ifconfig $eth down
sudo ifconfig $eth up
sudo ifconfig $eth $ip_address netmask $netmask

# Remove default route created by dhcpcd
sudo ip route del 0/0 dev $eth &> /dev/null

sudo systemctl stop dnsmasq

sudo rm -rf /etc/dnsmasq.d/* &> /dev/null

printf "interface=$eth\n\
bind-interfaces\n\
server=$dns_server\n\
domain-needed\n\
bogus-priv\n\
dhcp-range=$dhcp_range_start,$dhcp_range_end,$dhcp_time" > /tmp/custom-dnsmasq.conf

sudo cp /tmp/custom-dnsmasq.conf /etc/dnsmasq.d/custom-dnsmasq.conf
sudo systemctl start dnsmasq

# port forward to leased ip
miner_ip=$(awk '{ print $3 }' /var/lib/misc/dnsmasq.leases)
sudo iptables -t nat -A PREROUTING -p tcp -d 172.27.232.0/20 --dport 44158 -j DNAT --to-destination $miner_ip:44158