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Merge pull request 'Ztimson patch 16' (#16) from ztimson-patch-16 into master

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Reviewed-on: #16
This commit was merged in pull request #16.
This commit is contained in:
ztimson
2026-10-26 15:43:18 -04:00
parent 09387088df 4b2769aa98
commit 1d7813acff
2 changed files with 573 additions and 55 deletions
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fallback-ap.sh
+467 -53
View File
@@ -4,8 +4,9 @@ set -e
# Configuration =======================================================================================================
#
# Connection settings (SSID, passphrase, subnet, DHCP range, interface) can
# be supplied three ways, highest priority first:
# Connection settings (SSID, passphrase, subnet, DHCP range, interface,
# monitor interfaces, check mode) can be supplied three ways, highest
# priority first:
# 1. Environment variables (FALLBACK_AP_*) - used for headless installs.
# 2. The persisted config file below, written by `install`.
# 3. The hard-coded defaults in this block.
@@ -16,8 +17,39 @@ set -e
CONFIG_FILE="/etc/fallback-ap.conf"
if [ -f "$CONFIG_FILE" ]; then source "$CONFIG_FILE"; fi
# The interface the AP is created on. The AP is NEVER created on any other
# interface, regardless of what is being monitored.
WLAN0_IFACE="${FALLBACK_AP_IFACE:-${SAVED_IFACE:-wlan0}}"
# Which interfaces to watch for connectivity. If any of them is online, the
# AP stays off. Comma-separated list (e.g. "eth0,wlan1,wwan0").
# Leave BLANK to monitor all REAL interfaces: physical ethernet, wifi and
# cellular modems. Virtual interfaces (docker0, br-*, veth*, virbr*, tun/tap,
# wireguard, vlan, bridges, bonds, ...) are detected automatically and never
# count, so Docker/LXC/VM networking cannot keep the AP off.
# Note the missing colon in the expansion: an explicitly empty
# FALLBACK_AP_MONITOR_IFACE="" overrides a value saved in the config file.
MONITOR_IFACE="${FALLBACK_AP_MONITOR_IFACE-${SAVED_MONITOR_IFACE-}}"
MONITOR_IFACE="${MONITOR_IFACE// /}"
# Extra interfaces to ignore when monitoring all (comma-separated, globs
# allowed, e.g. "enx*,usb0"). Only needed for physical NICs you do not want
# to count; virtual interfaces are already excluded. Has no effect when
# MONITOR_IFACE names interfaces explicitly.
IGNORE_IFACE="${FALLBACK_AP_IGNORE_IFACE-${SAVED_IGNORE_IFACE-}}"
IGNORE_IFACE="${IGNORE_IFACE// /}"
# What "online" means:
# link - (default) a monitored interface is connected. An outage here is
# local and fixable; an upstream outage is not our problem, so
# the AP stays off. Fast and never flaps.
# internet - a monitored interface is connected AND can ping a target
# out of that specific interface (also detects dead uplinks)
CHECK_MODE="${FALLBACK_AP_CHECK_MODE:-${SAVED_CHECK_MODE:-link}}"
# Hosts pinged (space-separated, any one answering counts) in internet mode.
CHECK_TARGETS="${FALLBACK_AP_CHECK_TARGETS:-${SAVED_CHECK_TARGETS:-1.1.1.1 8.8.8.8}}"
AP_NAME="${FALLBACK_AP_SSID:-${SAVED_SSID:-$HOSTNAME}}"
AP_PASSWORD="${FALLBACK_AP_PASSWORD:-${SAVED_PASSWORD:-abcd1234}}"
AP_ENCRYPTION="${FALLBACK_AP_ENCRYPTION:-${SAVED_ENCRYPTION:-wpa-psk}}" # none | wpa-psk | sae
@@ -26,11 +58,18 @@ FALLBACK_AP_CIDR="${FALLBACK_AP_CIDR:-${SAVED_CIDR:-10.10.10.1/24}}"
FALLBACK_AP_DHCP_START_OCTET="${FALLBACK_AP_DHCP_START_OCTET:-${SAVED_DHCP_START_OCTET:-100}}"
FALLBACK_AP_DHCP_END_OCTET="${FALLBACK_AP_DHCP_END_OCTET:-${SAVED_DHCP_END_OCTET:-250}}"
AP_CIDR="$FALLBACK_AP_CIDR"
AP_NETWORK_BASE="${AP_CIDR%%/*}" # e.g. "10.10.10.1" out of "10.10.10.1/24"
AP_NETWORK_BASE="${AP_NETWORK_BASE%.*}" # e.g. "10.10.10"
DHCP_START="${AP_NETWORK_BASE}.${FALLBACK_AP_DHCP_START_OCTET}"
DHCP_END="${AP_NETWORK_BASE}.${FALLBACK_AP_DHCP_END_OCTET}"
# Values derived from the CIDR / DHCP settings. A function, because the
# `install` command-line flags can change those settings and need to
# recompute these.
compute_derived() {
AP_CIDR="$FALLBACK_AP_CIDR"
AP_NETWORK_BASE="${AP_CIDR%%/*}" # e.g. "10.10.10.1" out of "10.10.10.1/24"
AP_NETWORK_BASE="${AP_NETWORK_BASE%.*}" # e.g. "10.10.10"
DHCP_START="${AP_NETWORK_BASE}.${FALLBACK_AP_DHCP_START_OCTET}"
DHCP_END="${AP_NETWORK_BASE}.${FALLBACK_AP_DHCP_END_OCTET}"
}
compute_derived
# How often, while the AP has no clients, to stop the AP and give
# NetworkManager a chance to reconnect to a known Wi-Fi network.
@@ -44,6 +83,13 @@ RECOVERY_WINDOW=20
# we query it again.
STATE_SETTLE_DELAY=1
# Internet mode only: how often to run the ping checks, how many consecutive
# failed checks are needed before declaring "offline" (prevents the AP from
# flapping on a single dropped ping), and the per-ping timeout in seconds.
ONLINE_CHECK_INTERVAL=5
FAIL_THRESHOLD=3
PING_TIMEOUT=2
CONNECTION_NAME="Fallback AP"
SERVICE_NAME="fallback-ap"
SERVICE_FILE="/etc/systemd/system/$SERVICE_NAME.service"
@@ -56,6 +102,18 @@ STATE_FILE="$STATE_DIR/state"
# End of Configuration ================================================================================================
validate_check_mode() {
case "$CHECK_MODE" in
link|internet) ;;
*)
echo "Invalid check mode '$CHECK_MODE' (use: link | internet)"
exit 1
;;
esac
}
validate_check_mode
# Resolve the actual location of this script.
SCRIPT_PATH="$(readlink -f "$0")"
@@ -86,17 +144,210 @@ is_ap_on() {
}
is_wifi_connected() {
nmcli -t -f DEVICE,TYPE,STATE,CONNECTION device status 2>/dev/null |
awk -F: -v iface="$WLAN0_IFACE" -v ap="$CONNECTION_NAME" \
'$1 == iface && $2 == "wifi" && $3 == "connected" && $4 != ap {found=1} END {exit !found}'
# --- Connectivity monitoring -----------------------------------------------------------------------------------------
# True if no monitor interface is configured (= monitor everything).
monitor_all() {
[ -z "$MONITOR_IFACE" ]
}
# True if the AP interface is among the monitored interfaces. If it is not,
# a "recovery attempt" (taking the AP down to let wlan0 reconnect to Wi-Fi)
# could never change the result, so it is skipped.
monitors_wlan0() {
if monitor_all; then
return 0
fi
case ",${MONITOR_IFACE}," in
*",${WLAN0_IFACE},"*) return 0 ;;
esac
return 1
}
# A "real" interface is backed by hardware. Linux exposes this as a `device`
# link under /sys/class/net/<iface>/, which physical NICs (PCI, USB, SDIO,
# virtio, ...) have and virtual ones (docker0, veth*, br-*, tun*, wg*, vlan,
# bridges, bonds, dummy) do not. Cellular modems are the exception: NetworkManager
# names them after their control port (e.g. cdc-wdm0), which is not in
# /sys/class/net, so gsm/cdma types are accepted as-is.
is_real_interface() {
local dev="$1"
local type="$2"
case "$type" in
gsm|cdma) return 0 ;;
esac
[ -e "/sys/class/net/$dev/device" ]
}
# True if the device matches an entry of IGNORE_IFACE (globs allowed).
is_ignored_interface() {
local dev="$1"
local pattern
local -a patterns=()
IFS=',' read -r -a patterns <<< "$IGNORE_IFACE" || true
for pattern in "${patterns[@]}"; do
if [ -n "$pattern" ] && [[ "$dev" == $pattern ]]; then
return 0
fi
done
return 1
}
# Prints (one per line) the monitored devices that NetworkManager reports as
# connected, excluding the fallback AP connection itself.
# - Blank MONITOR_IFACE: every real (hardware-backed) ethernet, wifi or
# cellular device that is not in IGNORE_IFACE.
# - Otherwise: only the devices named in MONITOR_IFACE (any type).
# The state is matched with a prefix because nmcli reports values such as
# "connected (externally)" or "connected (site only)".
get_monitored_devices() {
local dev type
local all=0
if monitor_all; then
all=1
fi
while IFS=: read -r dev type; do
if [ -z "$dev" ]; then
continue
fi
if [ "$all" -eq 1 ]; then
case "$type" in
ethernet|wifi|gsm|cdma) ;;
*) continue ;;
esac
if ! is_real_interface "$dev" "$type"; then
continue
fi
if is_ignored_interface "$dev"; then
continue
fi
else
case ",${MONITOR_IFACE}," in
*",${dev},"*) ;;
*) continue ;;
esac
fi
echo "$dev"
done < <(
nmcli -t -f DEVICE,TYPE,STATE,CONNECTION device status 2>/dev/null |
awk -F: -v ap="$CONNECTION_NAME" \
'$3 ~ /^connected/ && $4 != ap {print $1 ":" $2}'
)
}
# Can this specific interface reach the internet? Pings are forced out of the
# given interface (-I) so another interface cannot answer on its behalf.
iface_has_internet() {
local dev="$1"
local target
for target in $CHECK_TARGETS; do
if ping -I "$dev" -c 1 -W "$PING_TIMEOUT" "$target" >/dev/null 2>&1; then
return 0
fi
done
return 1
}
# Is ANY monitored interface online right now (according to CHECK_MODE)?
check_online() {
local dev
while read -r dev; do
if [ -z "$dev" ]; then
continue
fi
if [ "$CHECK_MODE" = "link" ]; then
return 0
fi
if iface_has_internet "$dev"; then
return 0
fi
done < <(get_monitored_devices)
return 1
}
# Debounced wrapper around check_online, used by the main loop. Updates the
# `online`, `fail_count` and `last_online_check` variables of run().
# link mode: checked every tick, no debounce (cheap).
# internet mode: checked every ONLINE_CHECK_INTERVAL seconds, and only
# declared offline after FAIL_THRESHOLD consecutive failures.
# Coming back online is detected on the first success.
update_online() {
local now="$1"
local interval=0
local threshold=1
if [ "$CHECK_MODE" = "internet" ]; then
interval="$ONLINE_CHECK_INTERVAL"
threshold="$FAIL_THRESHOLD"
fi
if (( now - last_online_check < interval )); then
return 0
fi
last_online_check="$now"
if check_online; then
fail_count=0
online=1
else
fail_count=$((fail_count + 1))
if (( fail_count >= threshold )); then
online=0
fi
fi
}
wait_for_online() {
local timeout="$1"
local i
for ((i=0; i<timeout; i++)); do
if check_online; then
return 0
fi
sleep 1
done
return 1
}
# --- Wi-Fi bookkeeping -----------------------------------------------------------------------------------------------
get_wifi_connection() {
nmcli -t -f DEVICE,TYPE,STATE,CONNECTION device status 2>/dev/null |
awk -F: -v iface="$WLAN0_IFACE" \
'$1 == iface && $2 == "wifi" && $3 == "connected" {print $4; exit}'
'$1 == iface && $2 == "wifi" && $3 ~ /^connected/ {print $4; exit}'
}
@@ -148,27 +399,14 @@ wait_for_ap_state() {
}
wait_for_wifi() {
local timeout="$1"
for ((i=0; i<timeout*10; i++)); do
if is_wifi_connected; then
return 0
fi
sleep 0.1
done
return 1
}
# --- AP control (always on $WLAN0_IFACE only) ------------------------------------------------------------------------
start_ap() {
if is_ap_on; then
return 0
fi
log "Enabling AP: $AP_NAME"
log "Enabling AP: $AP_NAME (on $WLAN0_IFACE)"
nmcli connection up "$CONNECTION_NAME" ifname "$WLAN0_IFACE" >/dev/null 2>&1 || {
log "Failed to start AP"
@@ -207,23 +445,32 @@ stop_ap() {
return 0
}
# --- Main loop logic -------------------------------------------------------------------------------------------------
# Called once per second from run(). Relies on run()'s local variables
# (last_attempt, online, fail_count, last_online_check) via dynamic scoping.
tick() {
local now="$1"
if is_wifi_connected; then
update_online "$now"
if (( online )); then
remember_wifi
if is_ap_on; then
stop_ap
log "Connectivity available, shutting down fallback AP"
stop_ap || true
fi
set_state "wifi"
set_state "online"
last_attempt="$now"
return
fi
if ! is_ap_on; then
start_ap
log "No connectivity on monitored interface(s), starting fallback AP"
start_ap || true
set_state "fallback"
last_attempt="$now"
return
@@ -239,14 +486,20 @@ tick() {
return
fi
# Recovery only makes sense if wlan0 is one of the monitored interfaces:
# it works by briefly freeing wlan0 so it can reconnect to known Wi-Fi.
if ! monitors_wlan0; then
return
fi
if (( now - last_attempt >= RECOVERY_CHECK_INTERVAL )); then
last_attempt="$now"
attempt_recovery
attempt_recovery || true
fi
}
attempt_recovery() {
log "No AP clients, checking for known Wi-Fi (AP down for up to ${RECOVERY_WINDOW}s)"
log "No AP clients, checking for connectivity (AP down for up to ${RECOVERY_WINDOW}s)"
set_state "checking"
@@ -254,25 +507,27 @@ attempt_recovery() {
if is_ap_on; then
log "AP did not go down, aborting recovery attempt"
start_ap
start_ap || true
set_state "fallback"
return 1
fi
if wait_for_wifi "$RECOVERY_WINDOW"; then
if wait_for_online "$RECOVERY_WINDOW"; then
sleep "$STATE_SETTLE_DELAY"
if is_wifi_connected; then
log "Wi-Fi reconnected"
if check_online; then
log "Connectivity restored"
remember_wifi
set_state "wifi"
online=1
fail_count=0
set_state "online"
return 0
fi
fi
log "No Wi-Fi available, restoring AP"
log "No connectivity available, restoring AP"
start_ap
start_ap || true
set_state "fallback"
return 1
@@ -283,6 +538,10 @@ save_config() {
mkdir -p "$(dirname "$CONFIG_FILE")"
cat > "$CONFIG_FILE" <<EOF
SAVED_IFACE="$WLAN0_IFACE"
SAVED_MONITOR_IFACE="$MONITOR_IFACE"
SAVED_IGNORE_IFACE="$IGNORE_IFACE"
SAVED_CHECK_MODE="$CHECK_MODE"
SAVED_CHECK_TARGETS="$CHECK_TARGETS"
SAVED_SSID="$AP_NAME"
SAVED_PASSWORD="$AP_PASSWORD"
SAVED_ENCRYPTION="$AP_ENCRYPTION"
@@ -294,25 +553,115 @@ EOF
}
usage_install() {
cat <<EOF
Usage: $SCRIPT_PATH install [options]
Options (each overrides the matching FALLBACK_AP_* env var and any saved value):
--iface NAME Interface the AP is created on (default: wlan0)
--monitor-iface LIST Comma-separated interfaces to watch for connectivity.
Blank ("") monitors all REAL interfaces; virtual ones
(docker, veth, bridges, ...) are skipped (default: blank)
--ignore-iface LIST Comma-separated physical interfaces to ignore when
monitoring all; globs allowed, e.g. "enx*"
(default: none)
--check-mode MODE link | internet (default: link)
--check-targets "H.." Space-separated hosts to ping in internet mode
(default: "1.1.1.1 8.8.8.8")
--ssid NAME AP name (default: hostname)
--password PASS AP passphrase (default: abcd1234)
--encryption TYPE none | wpa-psk | sae (default: wpa-psk)
--cidr ADDR/MASK AP address and subnet (default: 10.10.10.1/24)
--dhcp-start OCTET First DHCP address, last octet (default: 100)
--dhcp-end OCTET Last DHCP address, last octet (default: 250)
-h, --help Show this help
Both "--opt value" and "--opt=value" are accepted. Precedence, highest first:
flags, FALLBACK_AP_* env vars, saved config file, built-in defaults.
Examples:
$SCRIPT_PATH install
$SCRIPT_PATH install --monitor-iface eth0,wwan0
$SCRIPT_PATH install --iface wlan1 --monitor-iface "" --check-mode internet
EOF
}
parse_install_args() {
local opt val
while [ $# -gt 0 ]; do
opt="$1"
case "$opt" in
-h|--help)
usage_install
exit 0
;;
--*=*)
val="${opt#*=}"
opt="${opt%%=*}"
shift
;;
--*)
if [ $# -lt 2 ]; then
echo "Option $opt requires a value."
exit 1
fi
val="$2"
shift 2
;;
*)
echo "Unknown argument: $opt"
usage_install
exit 1
;;
esac
case "$opt" in
--iface) WLAN0_IFACE="$val" ;;
--monitor-iface) MONITOR_IFACE="${val// /}" ;;
--ignore-iface) IGNORE_IFACE="${val// /}" ;;
--check-mode) CHECK_MODE="$val" ;;
--check-targets) CHECK_TARGETS="$val" ;;
--ssid) AP_NAME="$val" ;;
--password) AP_PASSWORD="$val" ;;
--encryption) AP_ENCRYPTION="$val" ;;
--cidr) FALLBACK_AP_CIDR="$val" ;;
--dhcp-start) FALLBACK_AP_DHCP_START_OCTET="$val" ;;
--dhcp-end) FALLBACK_AP_DHCP_END_OCTET="$val" ;;
*)
echo "Unknown option: $opt"
usage_install
exit 1
;;
esac
done
validate_check_mode
compute_derived
}
install() {
if [ "$EUID" -ne 0 ]; then
echo "Run this script as root."
exit 1
fi
parse_install_args "$@"
log "Installing NetworkManager fallback AP"
apt-get update
apt-get install -y network-manager iw
apt-get install -y network-manager iw iputils-ping
systemctl enable NetworkManager
systemctl start NetworkManager
mkdir -p "$STATE_DIR"
if is_wifi_connected; then
remember_wifi
fi
remember_wifi
create_connection
save_config
@@ -345,7 +694,15 @@ EOF
log "Script: $SCRIPT_PATH"
log "Config file: $CONFIG_FILE"
log "SSID: $AP_NAME"
log "Interface: $WLAN0_IFACE"
log "AP interface: $WLAN0_IFACE"
log "Monitored interfaces: ${MONITOR_IFACE:-all real interfaces}"
if monitor_all && [ -n "$IGNORE_IFACE" ]; then
log "Ignored interfaces: $IGNORE_IFACE"
fi
log "Check mode: $CHECK_MODE"
if [ "$CHECK_MODE" = "internet" ]; then
log "Ping targets: $CHECK_TARGETS"
fi
log "Network: $AP_CIDR"
log "DHCP: $DHCP_START - $DHCP_END"
log "Encryption: $AP_ENCRYPTION"
@@ -484,10 +841,56 @@ status() {
echo
echo "=== Config ($CONFIG_FILE) ==="
echo "SSID: $AP_NAME"
echo "Interface: $WLAN0_IFACE"
echo "AP interface: $WLAN0_IFACE"
echo "Monitored interfaces: ${MONITOR_IFACE:-all real interfaces}"
if monitor_all && [ -n "$IGNORE_IFACE" ]; then
echo "Ignored interfaces: $IGNORE_IFACE"
fi
echo "Check mode: $CHECK_MODE"
if [ "$CHECK_MODE" = "internet" ]; then
echo "Ping targets: $CHECK_TARGETS"
fi
echo "Network: $AP_CIDR"
echo "DHCP: $DHCP_START - $DHCP_END"
echo
echo "=== Connectivity ($CHECK_MODE) ==="
local dev found=0
while read -r dev; do
if [ -z "$dev" ]; then
continue
fi
found=1
if [ "$CHECK_MODE" = "internet" ]; then
if iface_has_internet "$dev"; then
echo "$dev: internet OK"
else
echo "$dev: connected, NO internet"
fi
else
echo "$dev: connected"
fi
done < <(get_monitored_devices)
if [ "$found" -eq 0 ]; then
echo "No monitored interface is connected"
fi
echo
echo "=== Connected but NOT counted (virtual / ignored / unmonitored) ==="
local monitored
monitored="$(get_monitored_devices)"
nmcli -t -f DEVICE,STATE,CONNECTION device status 2>/dev/null |
awk -F: -v ap="$CONNECTION_NAME" \
'$2 ~ /^connected/ && $3 != ap {print $1}' |
while read -r dev; do
if ! grep -Fxq "$dev" <<< "$monitored"; then
echo "$dev"
fi
done
echo
echo "=== Last Known Wi-Fi ==="
get_last_wifi || echo "None"
@@ -507,27 +910,36 @@ status() {
run() {
# These are shared with tick/update_online/attempt_recovery through
# dynamic scoping.
local last_attempt=0
local last_online_check=0
local fail_count=0
local online=0
local now
mkdir -p "$STATE_DIR"
log "Fallback AP service started"
log "Script: $SCRIPT_PATH"
log "AP interface: $WLAN0_IFACE | monitoring: ${MONITOR_IFACE:-all real interfaces} | mode: $CHECK_MODE"
exec 9>"$LOCK_FILE"
flock 9
if is_wifi_connected; then
if check_online; then
online=1
remember_wifi
set_state "wifi"
log "Wi-Fi already connected"
set_state "online"
log "Connectivity already available"
else
log "No Wi-Fi connection, starting fallback AP"
start_ap
log "No connectivity on monitored interface(s), starting fallback AP"
start_ap || true
set_state "fallback"
fi
last_online_check="$(date +%s)"
flock -u 9
while true; do
@@ -551,7 +963,8 @@ fi
case "${1:-}" in
install)
install
shift
install "$@"
;;
uninstall)
@@ -575,7 +988,8 @@ case "${1:-}" in
;;
*)
echo "Usage: $SCRIPT_PATH {install|uninstall|start|stop|status|run}"
echo "Usage: $SCRIPT_PATH {install [options]|uninstall|start|stop|status|run}"
echo " $SCRIPT_PATH install --help for install options"
exit 1
;;
esac
install.sh
+105 -1
View File
@@ -11,12 +11,57 @@ if [ "$EUID" -ne 0 ]; then
exit 1
fi
# Ask a question; Enter accepts the default.
prompt() {
local __var="$1" __question="$2" __default="$3" __answer=""
read -r -p "$__question [$__default]: " __answer < /dev/tty || __answer=""
printf -v "$__var" '%s' "${__answer:-$__default}"
}
# Like prompt, but "blank" is a legitimate value. Enter accepts the default;
# typing the clear word (e.g. "all" or "none") sets the value to empty.
prompt_blankable() {
local __var="$1" __question="$2" __default="$3" __clear="$4" __answer=""
read -r -p "$__question [${__default:-$__clear}]: " __answer < /dev/tty || __answer=""
case "$__answer" in
"") __answer="$__default" ;;
"$__clear") __answer="" ;;
esac
printf -v "$__var" '%s' "${__answer// /}"
}
# Ask until the answer is one of the allowed choices. Enter accepts the default.
prompt_choice() {
local __var="$1" __question="$2" __default="$3" __answer="" __opt
shift 3
while true; do
read -r -p "$__question [$__default]: " __answer < /dev/tty || __answer=""
__answer="${__answer:-$__default}"
for __opt in "$@"; do
if [ "$__answer" = "$__opt" ]; then
printf -v "$__var" '%s' "$__answer"
return 0
fi
done
echo " Please enter one of: $*"
done
}
# Lists wireless interfaces (those with a /sys/class/net/<iface>/wireless dir).
detect_wireless() {
local dir
for dir in /sys/class/net/*; do
if [ -d "$dir/wireless" ]; then
basename "$dir"
fi
done
}
EXISTING_CONFIG="/etc/fallback-ap.conf"
if [ -f "$EXISTING_CONFIG" ]; then
@@ -24,20 +69,79 @@ if [ -f "$EXISTING_CONFIG" ]; then
source "$EXISTING_CONFIG"
fi
DETECTED_WIFI="$(detect_wireless | tr '\n' ' ')"
DETECTED_WIFI="${DETECTED_WIFI% }"
DEFAULT_SSID="${SAVED_SSID:-$(hostname)}"
DEFAULT_PASSWORD="${SAVED_PASSWORD:-abcd1234}"
DEFAULT_IFACE="${SAVED_IFACE:-${DETECTED_WIFI%% *}}"
DEFAULT_IFACE="${DEFAULT_IFACE:-wlan0}"
DEFAULT_CIDR="${SAVED_CIDR:-10.10.10.1/24}"
DEFAULT_DHCP_START_OCTET="${SAVED_DHCP_START_OCTET:-100}"
DEFAULT_DHCP_END_OCTET="${SAVED_DHCP_END_OCTET:-250}"
DEFAULT_MONITOR_IFACE="${SAVED_MONITOR_IFACE-}"
DEFAULT_IGNORE_IFACE="${SAVED_IGNORE_IFACE-}"
DEFAULT_CHECK_MODE="${SAVED_CHECK_MODE:-link}"
DEFAULT_CHECK_TARGETS="${SAVED_CHECK_TARGETS:-1.1.1.1 8.8.8.8}"
# --- Access point ----------------------------------------------------------------------------------------------------
[ -z "${FALLBACK_AP_SSID:-}" ] && prompt FALLBACK_AP_SSID "Access point SSID" "$DEFAULT_SSID"
[ -z "${FALLBACK_AP_PASSWORD:-}" ] && prompt FALLBACK_AP_PASSWORD "Access point passphrase" "$DEFAULT_PASSWORD"
if [ -z "${FALLBACK_AP_IFACE:-}" ]; then
if [ -n "$DETECTED_WIFI" ]; then
echo "Detected Wi-Fi interfaces: $DETECTED_WIFI"
fi
prompt FALLBACK_AP_IFACE "Interface to create the access point on" "$DEFAULT_IFACE"
fi
[ -z "${FALLBACK_AP_CIDR:-}" ] && prompt FALLBACK_AP_CIDR "Access point subnet (CIDR)" "$DEFAULT_CIDR"
[ -z "${FALLBACK_AP_DHCP_START_OCTET:-}" ] && prompt FALLBACK_AP_DHCP_START_OCTET "DHCP range start (last octet)" "$DEFAULT_DHCP_START_OCTET"
[ -z "${FALLBACK_AP_DHCP_END_OCTET:-}" ] && prompt FALLBACK_AP_DHCP_END_OCTET "DHCP range end (last octet)" "$DEFAULT_DHCP_END_OCTET"
export FALLBACK_AP_SSID FALLBACK_AP_PASSWORD FALLBACK_AP_CIDR FALLBACK_AP_DHCP_START_OCTET FALLBACK_AP_DHCP_END_OCTET
# --- Connectivity monitoring -----------------------------------------------------------------------------------------
#
# The AP only starts when none of the monitored interfaces are online, and it
# is only ever created on the interface chosen above.
#
# These use "unset" (not "empty") to decide whether to ask, because an empty
# FALLBACK_AP_MONITOR_IFACE / FALLBACK_AP_IGNORE_IFACE is a valid answer
# meaning "all real interfaces" / "ignore nothing".
if [ -z "${FALLBACK_AP_MONITOR_IFACE+x}" ]; then
echo
echo "Which interfaces should count as 'online'? Enter a comma-separated list"
echo "(e.g. eth0,wlan0), or 'all' for every real interface. Virtual interfaces"
echo "(docker, veth, bridges, VPNs) are skipped automatically."
prompt_blankable FALLBACK_AP_MONITOR_IFACE "Interfaces to monitor" "$DEFAULT_MONITOR_IFACE" "all"
fi
if [ -z "$FALLBACK_AP_MONITOR_IFACE" ] && [ -z "${FALLBACK_AP_IGNORE_IFACE+x}" ]; then
echo
echo "Any physical interfaces to ignore (globs allowed, e.g. enx*,usb0)?"
prompt_blankable FALLBACK_AP_IGNORE_IFACE "Interfaces to ignore" "$DEFAULT_IGNORE_IFACE" "none"
fi
if [ -z "${FALLBACK_AP_CHECK_MODE:-}" ]; then
echo
echo "How should 'online' be determined?"
echo " link - the interface is connected (an upstream outage keeps the AP off)"
echo " internet - the interface is connected AND can ping out"
prompt_choice FALLBACK_AP_CHECK_MODE "Check mode" "$DEFAULT_CHECK_MODE" link internet
fi
if [ "$FALLBACK_AP_CHECK_MODE" = "internet" ] && [ -z "${FALLBACK_AP_CHECK_TARGETS:-}" ]; then
prompt FALLBACK_AP_CHECK_TARGETS "Hosts to ping (space-separated)" "$DEFAULT_CHECK_TARGETS"
fi
export FALLBACK_AP_SSID FALLBACK_AP_PASSWORD FALLBACK_AP_IFACE FALLBACK_AP_CIDR FALLBACK_AP_DHCP_START_OCTET FALLBACK_AP_DHCP_END_OCTET
export FALLBACK_AP_CHECK_MODE
[ -n "${FALLBACK_AP_MONITOR_IFACE+x}" ] && export FALLBACK_AP_MONITOR_IFACE
[ -n "${FALLBACK_AP_IGNORE_IFACE+x}" ] && export FALLBACK_AP_IGNORE_IFACE
[ -n "${FALLBACK_AP_CHECK_TARGETS+x}" ] && export FALLBACK_AP_CHECK_TARGETS
echo
echo "Downloading fallback-ap..."
curl -fsSL "$SCRIPT_URL" -o "$INSTALL_PATH"
chmod +x "$INSTALL_PATH"