make it actually work

.gitignore

@@ -1,4 +1,5 @@
-config.sh
+.idea
+config/config.sh
 
 # ---> Python
 # Byte-compiled / optimized / DLL files

bridge-install.sh

@@ -6,17 +6,17 @@
 # Config
 
 SOURCE=${BASH_SOURCE[0]}
-while [ -L "$SOURCE" ]; do # resolve $SOURCE until the file is no longer a symlink
+while [ -L "$SOURCE" ]; do
-  DIR=$( cd -P "$( dirname "$SOURCE" )" >/dev/null 2>&1 && pwd )
+  DIR=$(cd -P "$(dirname "$SOURCE")" >/dev/null 2>&1 && pwd)
   SOURCE=$(readlink "$SOURCE")
-  [[ $SOURCE != /* ]] && SOURCE=$DIR/$SOURCE # if $SOURCE was a relative symlink, we need to resolve it relative to the path where the symlink file was located
+  [[ $SOURCE != /* ]] && SOURCE=$DIR/$SOURCE
 done
-DIR=$( cd -P "$( dirname "$SOURCE" )" >/dev/null 2>&1 && pwd )
+DIR=$(cd -P "$(dirname "$SOURCE")" >/dev/null 2>&1 && pwd)
 
-if [[ -f "$DIR/config.sh" ]]; then
+if [[ -f "$DIR/config/config.sh" ]]; then
-  source "$DIR/config.sh"
+  source "$DIR/config/config.sh"
 else
-  echo "config.sh missing!"
+  echo "$DIR/config/config.sh missing!"
   exit 1
 fi
 
@@ -25,12 +25,35 @@ fi
 
 # Must be run as root
 if [ "$(id -u)" -ne 0 ]; then
-        echo 'This script must be run as root.' >&2
+  echo 'This script must be run as root.' >&2
-        exit 1
+  exit 1
 fi
 
+# Reset interfaces
+iptables -X
+iptables -F
+iptables -t nat -X
+iptables -t nat -F
+echo "Cleared iptables"
+
+ifconfig $WLAN_IFACE down
+ifconfig $WLAN_IFACE hw ether $(ethtool -P $WLAN_IFACE | awk '{print $3}')
+ifconfig $WLAN_IFACE up
+echo "Reset $WLAN_IFACE"
+
+while true; do
+  WLAN_IFACE_IP=$(ip -4 -br addr show $WLAN_IFACE | grep -Po "\\d+\\.\\d+\\.\\d+\\.\\d+")
+  if [ -n "${WLAN_IFACE_IP}" ]; then
+    echo "Got it!"
+    break
+  fi
+  echo "Waiting for $WLAN_IFACE to get an IP..."
+  sleep 5
+done
+
 # We only need to get the $WLAN_IFACE IP address and will copy it over to $ETH_IFACE later
-WLAN_IFACE_IP=$(ip -4 -br addr show $WLAN_IFACE | grep -Po "\\d+\\.\\d+\\.\\d+\\.\\d+")
+WLAN_NETMASK=$(ip addr show $WLAN_IFACE | grep -w inet | awk '{print $2}' | cut -d'/' -f2)
+WLAN_NETMASK_CIDR=$(ip addr show $WLAN_IFACE | grep -w inet | awk '{print $2}' | cut -d'/' -f2)
 
 if $NON_INTERACTIVE; then
   NON_INTERACTIVE_APT="-y"
@@ -41,16 +64,18 @@ fi
 # ==============================================================================
 # Install stuff
 
-echo "# INSTALL THINGS #"
+echo -e "\n# INSTALL THINGS #"
 
-echo -e "\nUpdating...\n\n"
+echo -e "Updating...\n\n"
 
+service systemd-resolved start
+sudo systemctl stop dnsmasq
 apt-get update
 apt-get upgrade $NON_INTERACTIVE_APT
 
 echo -e "\n"
 
-THINGS_TO_INSTALL="parprouted dhcp-helper net-tools"
+THINGS_TO_INSTALL="parprouted dhcp-helper net-tools ethtool dnsmasq"
 
 if ! $NON_INTERACTIVE; then
   echo "Going to install: $THINGS_TO_INSTALL"
@@ -64,7 +89,9 @@ apt-get install $NON_INTERACTIVE_APT $THINGS_TO_INSTALL
 echo -e "\n\nSetting up services...\n"
 
 systemctl stop dhcp-helper
-systemctl enable dhcp-helper
+systemctl disable dhcp-helper # remember to enable it later
+sudo systemctl stop dnsmasq
+sudo systemctl disable dnsmasq
 
 if ! $NON_INTERACTIVE; then
   echo -e "\n\nGoing to replace networking with systemd-networkd."
@@ -77,10 +104,10 @@ apt-get --autoremove $NON_INTERACTIVE_APT purge ifupdown dhcpcd5 isc-dhcp-client
 echo -e "\n\nConnecting to WiFi..."
 
 WPA_SUPP_FILE="/etc/wpa_supplicant/wpa_supplicant-$WLAN_IFACE.conf"
-cat > "$WPA_SUPP_FILE" <<EOF
+cat >"$WPA_SUPP_FILE" <<EOF
 ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
 update_config=1
-country=US
+country=USifconfig $WLAN_IFACE
 network={
  ssid="$WIFI_SSID"
  scan_ssid=1
@@ -101,11 +128,10 @@ systemctl status --no-pager wpa_supplicant@$WLAN_IFACE.service
 echo ""
 ifconfig $WLAN_IFACE
 
-
+echo -e "\n\n"
-echo -e "\n\n"https://raspberrypi.stackexchange.com/questions/88954/workaround-for-a-wifi-bridge-on-a-raspberry-pi-with-proxy-arp
+ifconfig $WLAN_IFACE
-
 NET_CONF_FILE="/etc/systemd/network/08-$WLAN_IFACE.network"
-cat > "$NET_CONF_FILE" <<EOF
+cat >"$NET_CONF_FILE" <<EOF
 [Match]
 Name=$WLAN_IFACE
 [Network]
@@ -119,106 +145,22 @@ EOF
 echo "Created network config: $WLAN_IFACE"
 echo -e "Finishing systemd-networkd install...\n\n"
 apt-get install $NON_INTERACTIVE_APT libnss-resolve
-systemctl enable --now systemd-resolved.service
 ln -sf /run/systemd/resolve/stub-resolv.conf /etc/resolv.conf
-systemctl enable --now systemd-networkd.service
+systemctl enable --now systemd-resolved.service
+systemctl restart systemd-networkd.service
 
 echo -e "\n\nInstall complete! Ignore any service errors for now..."
 
-# ==============================================================================
-# Create bridge interface
-
-echo -e "\n# BRIDGE $WLAN_IFACE TO $ETH_IFACE #"
-
-# IP="128.198.192.233"
-# MAC="f0:1f:af:6d:fd:54"
-# ebtables -F
-# ebtables -F -t nat
-# ebtables -t nat -A PREROUTING -i $WLAN_IFACE -j redirect --redirect-target ACCEPT
-# ebtables -t nat -A PREROUTING -i $ETH_IFACE -j redirect --redirect-target ACCEPT
-
-
-# This works but nat and is unreliable and breaks DHCP
-# IP_OTHR="128.198.192.233"
-# iptables -F
-# iptables -F -t nat
-# iptables -t nat -A PREROUTING  -d $IP_OTHR -i  $ETH_IFACE -j DNAT --to-destination $WLAN_IFACE_IP
-# iptables -t nat -A PREROUTING  -d $WLAN_IFACE_IP -i $WLAN_IFACE -j DNAT --to-destination $IP_OTHR
-# iptables -t nat -A POSTROUTING -s $WLAN_IFACE_IP          -j SNAT --to-source      $IP_OTHR
-# iptables -t nat -A POSTROUTING -s $IP_OTHR          -j SNAT --to-source      $WLAN_IFACE_IP
-
 # ==============================================================================
 # Set up configs
 
 echo -e "\n# SET UP CONFIG FILES #"
 
 sed -i'' 's/#net.ipv4.ip_forward=1/net.ipv4.ip_forward=1/' /etc/sysctl.conf
-sudo sysctl -p /etc/sysctl.conf
+sysctl -p /etc/sysctl.conf
 echo "Set net.ipv4.ip_forward=1 in /etc/sysctl.conf"
 
-DHCP_HELPER_CONF="/etc/default/dhcp-helper"
+mkdir -p /var/lib/dnsmasq/
-for ip in $DHCP_SERVERS; do
+echo "Created /var/lib/dnsmasq/"
-  DHCP_SERVERS_CONF+=" -s $ip"
-done
-cat > "$DHCP_HELPER_CONF" <<EOF
-# Relay DHCP requests as broadcast to $WLAN_IFACE
-DHCPHELPER_OPTS="$DHCP_SERVERS_CONF"
-EOF
-echo "Created dhcp-helper config: $DHCP_HELPER_CONF"
-
-# Enable IP forwarding for $WLAN_IFACE if it's not already enabled.
-# grep '^option ip-forwarding 1$' /etc/dhcpcd.conf || printf "option ip-forwarding 1\n" >> /etc/dhcpcd.conf
-
-# Disable dhcpcd control of $ETH_IFACE.
-# grep "^denyinterfaces ${ETH_IFACE}\$" /etc/dhcpcd.conf || printf "denyinterfaces $ETH_IFACE\n" >> /etc/dhcpcd.conf
-
-# Enable avahi reflector if it's not already enabled.
-sed -i'' 's/#enable-reflector=no/enable-reflector=yes/' /etc/avahi/avahi-daemon.conf
-grep '^enable-reflector=yes$' /etc/avahi/avahi-daemon.conf || {
-  printf "something went wrong...\n\n"
-  printf "Manually set 'enable-reflector=yes in /etc/avahi/avahi-daemon.conf'\n"
-}
-echo "Enabled avahi reflector."
-
-PARPROUTED_SERVICE="/etc/systemd/system/parprouted.service"
-cat > "$PARPROUTED_SERVICE" <<EOF
-[Unit]
-Description=proxy arp routing service
-Documentation=https://raspberrypi.stackexchange.com/q/88954/79866
-Requires=sys-subsystem-net-devices-$WLAN_IFACE.device
-# dhcpcd.service
-After=sys-subsystem-net-devices-$WLAN_IFACE.device
-# dhcpcd.service
-
-[Service]
-Type=forking
-# Restart until $WLAN_IFACE gained carrier
-Restart=on-failure
-RestartSec=5
-TimeoutStartSec=30
-# clone the dhcp-allocated IP to $ETH_IFACE so dhcp-helper will relay for the correct subnet
-ExecStartPre=/bin/bash -c '/sbin/ip addr add $WLAN_IFACE_IP/32 dev $ETH_IFACE'
-ExecStartPre=/sbin/ip link set dev $ETH_IFACE up
-ExecStartPre=/sbin/ip link set $WLAN_IFACE promisc on
-ExecStart=-/usr/sbin/parprouted $ETH_IFACE $WLAN_IFACE
-ExecStopPost=/sbin/ip link set $WLAN_IFACE promisc off
-ExecStopPost=/sbin/ip link set dev $ETH_IFACE down
-ExecStopPost=/bin/bash -c '/sbin/ip addr del $WLAN_IFACE_IP/32 dev $ETH_IFACE'
-
-[Install]
-WantedBy=wpa_supplicant.service
-EOF
-echo "Created systemd service: $PARPROUTED_SERVICE"
-
-systemctl daemon-reload
-systemctl enable --now parprouted dhcp-helper
-systemctl restart parprouted dhcp-helper
-echo -e "Enabled and started parprouted and dhcp-helper"
-
-echo -e "Waiting 5 seconds...\n"
-sleep 5
-
-systemctl status --no-pager parprouted
-systemctl status --no-pager dhcp-helper
 
 echo -e "\n\n\n==============\nDone!\nNow reboot!"

bridge/bridge-lan.sh

@@ -0,0 +1,103 @@
+#!/bin/bash
+
+SOURCE=${BASH_SOURCE[0]}
+while [ -L "$SOURCE" ]; do # resolve $SOURCE until the file is no longer a symlink
+  DIR=$(cd -P "$(dirname "$SOURCE")" >/dev/null 2>&1 && pwd)
+  SOURCE=$(readlink "$SOURCE")
+  [[ $SOURCE != /* ]] && SOURCE=$DIR/$SOURCE # if $SOURCE was a relative symlink, we need to resolve it relative to the path where the symlink file was located
+done
+DIR=$(cd -P "$(dirname "$SOURCE")" >/dev/null 2>&1 && pwd)
+
+if [[ -f "$DIR/../config/config.sh" ]]; then
+  . "$DIR/../config/config.sh"
+else
+  echo "$DIR/../config/config.sh missing!"
+  exit 1
+fi
+
+if [ "$(id -u)" -ne 0 ]; then
+  echo 'This script must be run as root.' >&2
+  exit 1
+fi
+
+. "$DIR/get-dhcp-dns.sh"
+
+# ==============================================================================
+
+PRIVATE_LAN_IP="192.168.2.1"
+BRIDGED_CLIENT_IP="192.168.2.2"
+
+# Configure the wired interface with the bridge IP address
+ifconfig $ETH_IFACE $PRIVATE_LAN_IP netmask 255.255.255.0 up
+
+# Mirror the DNS servers to the private LAN
+DHCP_DNS=($(get_dns_servers "$WLAN_IFACE"))
+if [ -n "$DHCP_DNS" ]; then
+  dns_servers_config=""
+  for server in "${DHCP_DNS[@]}"; do
+    dns_servers_config+="server=$server"$'\n'
+  done
+
+  dhcp_opt_6_config="dhcp-option=6"
+  for server in "${DHCP_DNS[@]}"; do
+    dhcp_opt_6_config+=",$server"
+  done
+  echo "Mirrored WLAN DHCP DNS servers: ${DHCP_DNS[*]}"
+else
+  dns_servers_config="""server=1.1.1.1
+server=1.0.0.1"""
+  dhcp_opt_6_config=""
+fi
+
+# Also mirror DNS domain
+DHCP_DNS_DOMAIN=$(get_dns_domain $WLAN_IFACE)
+if [ -n "$DHCP_DNS_DOMAIN" ]; then
+  dns_domain_config="domain=$DHCP_DNS_DOMAIN"
+  echo "Mirrored WLAN DHCP DNS domain: $DHCP_DNS_DOMAIN"
+else
+  dns_domain_config=""
+fi
+
+# Create the dnsmasq.conf file with the generated DNS server config
+cat >/etc/dnsmasq.conf <<EOL
+interface=$ETH_IFACE
+domain-needed
+bogus-priv
+no-resolv
+$dns_servers_config
+$dhcp_opt_6_config
+$dns_domain_config
+listen-address=::1,127.0.0.1,$PRIVATE_LAN_IP
+expand-hosts
+dhcp-range=$PRIVATE_LAN_IP,$BRIDGED_CLIENT_IP,12h
+dhcp-option=option:router,$PRIVATE_LAN_IP
+dhcp-authoritative
+dhcp-leasefile=/var/lib/dnsmasq/dnsmasq.leases
+EOL
+echo "Wrote to /etc/dnsmasq.conf"
+
+# Configure NAT to forward traffic between the private LAN and the WLAN
+iptables -X
+iptables -F
+iptables -t nat -X
+iptables -t nat -F
+echo "Reset iptables"
+
+# Route/forward traffic between nets
+iptables -I INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT
+iptables -I FORWARD -m state --state RELATED,ESTABLISHED -j ACCEPT
+iptables -t nat -I POSTROUTING -o $WLAN_IFACE -j MASQUERADE
+echo "Created iptables to route traffic between nets"
+
+# Port forward everything to the single client
+iptables -t nat -A PREROUTING -i $WLAN_IFACE -j DNAT --to-destination $BRIDGED_CLIENT_IP
+iptables -t nat -A POSTROUTING -o $ETH_IFACE -j MASQUERADE
+echo "Port forwarded everything to the single bridged client"
+
+echo -e "\nRestarting dnsmasq...\n"
+service systemd-resolved stop
+# systemctl enable --now dnsmasq
+systemctl restart dnsmasq
+echo -e "\n"
+sleep 5
+systemctl status --no-pager dnsmasq

bridge/bridge-reset.sh

@@ -0,0 +1,95 @@
+#!/bin/bash
+
+# ==============================================================================
+# Config
+
+SOURCE=${BASH_SOURCE[0]}
+while [ -L "$SOURCE" ]; do
+  DIR=$(cd -P "$(dirname "$SOURCE")" >/dev/null 2>&1 && pwd)
+  SOURCE=$(readlink "$SOURCE")
+  [[ $SOURCE != /* ]] && SOURCE=$DIR/$SOURCE
+done
+DIR=$(cd -P "$(dirname "$SOURCE")" >/dev/null 2>&1 && pwd)
+
+if [[ -f "$DIR/../config/config.sh" ]]; then
+  source "$DIR/../config/config.sh"
+else
+  echo "$DIR/../config/config.sh missing!"
+  exit 1
+fi
+
+# Must be run as root
+if [ "$(id -u)" -ne 0 ]; then
+  echo 'This script must be run as root.' >&2
+  exit 1
+fi
+
+# ==============================================================================
+
+iptables -X
+iptables -F
+iptables -t nat -X
+iptables -t nat -F
+echo "Cleared iptables"
+
+# Restore MAC address to WLAN interface
+ifconfig $WLAN_IFACE down
+ifconfig $WLAN_IFACE hw ether "$(ethtool -P $WLAN_IFACE | awk '{print $3}')"
+ifconfig $WLAN_IFACE up
+echo "Reset $WLAN_IFACE"
+
+while true; do
+  WLAN_IFACE_IP=$(ip -4 -br addr show $WLAN_IFACE | grep -Po "\\d+\\.\\d+\\.\\d+\\.\\d+")
+  if [ -n "${WLAN_IFACE_IP}" ]; then
+    echo "Got it!"
+    break
+  fi
+  echo "Waiting for $WLAN_IFACE to get an IP..."
+  sleep 5
+done
+
+service systemd-resolved start
+sudo systemctl stop dnsmasq
+echo "Reset DNS services"
+
+echo -e "\nConnecting to WiFi..."
+
+WPA_SUPP_FILE="/etc/wpa_supplicant/wpa_supplicant-$WLAN_IFACE.conf"
+cat >"$WPA_SUPP_FILE" <<EOF
+ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
+update_config=1
+country=USifconfig $WLAN_IFACE
+network={
+ ssid="$WIFI_SSID"
+ scan_ssid=1
+ key_mgmt=WPA-EAP
+ eap=PEAP
+ identity="$WIFI_USERNAME"
+ password="$WIFI_PWD"
+ phase1="peaplabel=0"
+ phase2="auth=MSCHAPV2"
+}
+EOF
+chmod 600 "$WPA_SUPP_FILE"
+echo "Created wpa_supplicant: $WPA_SUPP_FILE"
+systemctl disable wpa_supplicant.service
+systemctl stop wpa_supplicant.service
+systemctl enable --now wpa_supplicant@$WLAN_IFACE.service
+systemctl status --no-pager wpa_supplicant@$WLAN_IFACE.service
+echo ""
+ifconfig $WLAN_IFACE
+
+echo -e "\n\n"
+ifconfig $WLAN_IFACE
+NET_CONF_FILE="/etc/systemd/network/08-$WLAN_IFACE.network"
+cat >"$NET_CONF_FILE" <<EOF
+[Match]
+Name=$WLAN_IFACE
+[Network]
+IPForward=yes
+DHCP=yes
+EOF
+echo "Created network config: $WLAN_IFACE"
+
+echo "Restarting systemd-networkd..."
+systemctl restart systemd-networkd.service

bridge/clone-client-mac.sh

@@ -0,0 +1,52 @@
+#!/bin/bash
+
+# ==============================================================================
+# Config and setup
+
+SOURCE=${BASH_SOURCE[0]}
+while [ -L "$SOURCE" ]; do
+  DIR=$(cd -P "$(dirname "$SOURCE")" >/dev/null 2>&1 && pwd)
+  SOURCE=$(readlink "$SOURCE")
+  [[ $SOURCE != /* ]] && SOURCE=$DIR/$SOURCE
+done
+DIR=$(cd -P "$(dirname "$SOURCE")" >/dev/null 2>&1 && pwd)
+
+if [[ -f "$DIR/../config/config.sh" ]]; then
+  . "$DIR/../config/config.sh"
+else
+  echo "$DIR/../config/config.sh missing!"
+  exit 1
+fi
+
+if [ "$(id -u)" -ne 0 ]; then
+  echo 'This script must be run as root.' >&2
+  exit 1
+fi
+
+. "$DIR/get_client_mac_address.sh"
+
+# ==============================================================================
+
+MAC_OTHR=$(get_client_mac_address $ETH_IFACE)
+if [ -z "$MAC_OTHR" ]; then
+  echo "Bridged client not found! MAC address was empty."
+  exit 1
+else
+  echo "Cloning MAC: $MAC_OTHR"
+fi
+
+# Clone MAC address of the wired-only device to the WiFi device
+ifconfig $WLAN_IFACE down
+ifconfig $WLAN_IFACE hw ether $MAC_OTHR
+ifconfig $WLAN_IFACE up
+echo "Set $WLAN_IFACE MAC to $MAC_OTHR"
+
+while true; do
+  WLAN_IFACE_IP=$(ip -4 -br addr show $WLAN_IFACE | grep -Po "\\d+\\.\\d+\\.\\d+\\.\\d+")
+  if [ -n "${WLAN_IFACE_IP}" ]; then
+    echo "Got DHCP IP: $WLAN_IFACE_IP"
+    break
+  fi
+  echo "Waiting for $WLAN_IFACE to get an IP..."
+  sleep 5
+done

bridge/get-dhcp-dns.sh

@@ -0,0 +1,9 @@
+get_dns_servers() {
+  local interface="$1"
+  resolvectl status | awk -v iface="Link [0-9]+ \\($interface\\)" '$0 ~ iface {flag=1; next} flag && /DNS Servers/ {gsub(",", ""); print; exit}' | awk -F ': ' '{print $2}'
+}
+
+get_dns_domain() {
+  local interface="$1"
+  resolvectl status | awk -v iface="Link [0-9]+ \\($interface\\)" '$0 ~ iface {flag=1; next} flag && /DNS Domain/ {print $3; exit}'
+}

bridge/get_client_mac_address.sh

@@ -0,0 +1,20 @@
+function get_client_mac_address() {
+  # Usage: get_client_mac_address <interface_name>
+  local ETH_IFACE="$1"
+  local TARGET_IP="192.168.2.2"
+
+  # Check if the interface is plugged in
+  if ip link show "$ETH_IFACE" | grep -q "state UP"; then
+    local MAC_ADDRESS=$(arp -i "$ETH_IFACE" -n | grep "$TARGET_IP" | awk '{print $3}')
+
+    if [ -n "$MAC_ADDRESS" ]; then
+      echo "$MAC_ADDRESS"
+    else
+      echo "Could not find the MAC address of the connected device with IP address $TARGET_IP"
+      exit 1
+    fi
+  else
+    echo "Interface $ETH_IFACE is not plugged in."
+    exit 1
+  fi
+}

config/config.sh.example

@@ -11,5 +11,9 @@ WIFI_SSID="Example-Network"
 WIFI_USERNAME="username"
 WIFI_PWD="password"
 
+# "transparent": the bridge device clones the client's MAC address and NATs traffic to a private LAN. Only supports one bridged client.
+# TODO: support bridging multiple clients connected to an ethernet hub
+# BRIDGE_MODE="transparent"
+
 # Don't prompt the user for confirmation
 NON_INTERACTIVE=false

wlan2eth.service

@@ -0,0 +1,14 @@
+# /etc/systemd/system/wlan2eth.service
+[Unit]
+Description=wlan2eth
+Wants=basic.target
+After=basic.target network.target
+
+[Service]
+SyslogIdentifier=wlan2eth
+ExecStart=/bin/bash /opt/wlan2eth/wlan2eth.sh
+Restart=always
+RestartSec=2
+
+[Install]
+WantedBy=multi-user.target

wlan2eth.sh

@@ -0,0 +1,50 @@
+#!/usr/bin/env bash
+
+# ==============================================================================
+# Config
+
+SOURCE=${BASH_SOURCE[0]}
+while [ -L "$SOURCE" ]; do
+  DIR=$(cd -P "$(dirname "$SOURCE")" >/dev/null 2>&1 && pwd)
+  SOURCE=$(readlink "$SOURCE")
+  [[ $SOURCE != /* ]] && SOURCE=$DIR/$SOURCE
+done
+DIR=$(cd -P "$(dirname "$SOURCE")" >/dev/null 2>&1 && pwd)
+
+if [[ -f "$DIR/config/config.sh" ]]; then
+  source "$DIR/config/config.sh"
+else
+  echo "config/config.sh missing!"
+  exit 1
+fi
+
+# Must be run as root
+if [ "$(id -u)" -ne 0 ]; then
+  echo 'This script must be run as root.' >&2
+  exit 1
+fi
+
+# ==============================================================================
+
+PREV_STATUS=""
+
+while true; do
+  STATUS=$(cat /sys/class/net/$ETH_IFACE/carrier 2>/dev/null)
+
+  if [ "$STATUS" != "$PREV_STATUS" ]; then
+    if [ "$STATUS" == "0" ]; then
+      echo -e "\n----> Interface $ETH_IFACE has been unplugged."
+      bash "$DIR/bridge/bridge-reset.sh"
+      echo -e "--> Reset complete\n"
+    elif [ "$STATUS" == "1" ]; then
+      echo -e "\n----> Interface $ETH_IFACE has been plugged in."
+      bash "$DIR/bridge/bridge-lan.sh"
+      bash "$DIR/bridge/clone-client-mac.sh"
+      echo -e "--> Bridge complete\n"
+    else
+      echo -e "\n----> Interface $ETH_IFACE not found, doing nothing...\n"
+    fi
+    PREV_STATUS="$STATUS"
+  fi
+  sleep 1
+done