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Diffstat (limited to 'src/wg-quick.bash')
-rwxr-xr-x | src/wg-quick.bash | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/src/wg-quick.bash b/src/wg-quick.bash new file mode 100755 index 0000000..e686d73 --- /dev/null +++ b/src/wg-quick.bash @@ -0,0 +1,209 @@ +#!/bin/bash +# +# Copyright (c) 2016 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved. +# + +set -e -o pipefail +shopt -s extglob + +SELF="$(readlink -f "${BASH_SOURCE[0]}")" +export PATH="${SELF%/*}:$PATH" + +WG_CONFIG="" +INTERFACE="" +ADDRESSES=( ) +PRE_UP="" +POST_UP="" +PRE_DOWN="" +POST_DOWN="" +SAVE_CONFIG=0 +CONFIG_FILE="" +PROGRAM="${0##*/}" +ARGS=( "$@" ) + +parse_options() { + local interface_section=0 line key value + CONFIG_FILE="$1" + [[ $CONFIG_FILE =~ ^[a-zA-Z0-9_=+.-]{1,16}$ ]] && CONFIG_FILE="/etc/wireguard/$CONFIG_FILE.conf" + [[ -e $CONFIG_FILE ]] || die "\`$CONFIG_FILE' does not exist" + [[ $CONFIG_FILE =~ /?([a-zA-Z0-9_=+.-]{1,16})\.conf$ ]] || die "The config file must be a valid interface name, followed by .conf" + INTERFACE="${BASH_REMATCH[1]}" + shopt -s nocasematch + while read -r line; do + key="${line%%=*}"; key="${key##*( )}"; key="${key%%*( )}" + value="${line#*=}"; value="${value##*( )}"; value="${value%%*( )}" + [[ $key == "["* ]] && interface_section=0 + [[ $key == "[Interface]" ]] && interface_section=1 + if [[ $interface_section -eq 1 ]]; then + case "$key" in + Address) ADDRESSES+=( ${value//,/ } ); continue ;; + PreUp) PRE_UP="$value"; continue ;; + PreDown) PRE_DOWN="$value"; continue ;; + PostUp) POST_UP="$value"; continue ;; + PostDown) POST_DOWN="$value"; continue ;; + SaveConfig) read_bool SAVE_CONFIG "$value"; continue ;; + esac + fi + WG_CONFIG+="$line"$'\n' + done < "$CONFIG_FILE" + shopt -u nocasematch +} + +read_bool() { + local -n out="$1" + case "$2" in + true) out=1 ;; + false) out=0 ;; + *) die "\`$2' is neither true nor false" + esac +} + +cmd() { + echo "[#] $*" >&2 + "$@" +} + +die() { + echo "$PROGRAM: $*" >&2 + exit 1 +} + +auto_su() { + [[ $UID == 0 ]] || exec sudo -p "$PROGRAM must be run as root. Please enter the password for %u to continue: " "$SELF" "${ARGS[@]}" +} + +add_if() { + cmd ip link add "$INTERFACE" type wireguard +} + +del_if() { + if [[ $(ip route show table all) =~ .*\ dev\ $INTERFACE\ table\ ([0-9]+)\ .* ]]; then + cmd ip rule delete table "${BASH_REMATCH[1]}" + cmd ip rule delete table main suppress_prefixlength 0 2>/dev/null + fi + cmd ip link delete dev "$INTERFACE" +} + +up_if() { + cmd ip link set "$INTERFACE" up +} + +add_addr() { + cmd ip address add "$1" dev "$INTERFACE" +} + +add_route() { + if [[ $1 == 0.0.0.0/0 || $1 == ::/0 ]]; then + add_default "$1" + else + cmd ip route add "$1" dev "$INTERFACE" + fi +} + +add_default() { + [[ $(join <(wg show "$INTERFACE" allowed-ips) <(wg show "$INTERFACE" endpoints)) =~ .*\ ${1//./\\.}\ ([0-9.:a-f]+):[0-9]+$ ]] && local endpoint="${BASH_REMATCH[1]}" + [[ -n $endpoint ]] || return 0 + local table=51820 + while [[ -n $(ip route show table $table) ]]; do ((table++)); done + cmd ip route add "$1" dev "$INTERFACE" table $table + cmd ip rule add not to "$endpoint" table $table + cmd ip rule add table main suppress_prefixlength 0 +} + +set_config() { + cmd wg setconf "$INTERFACE" <(echo "$WG_CONFIG") +} + +save_config() { + local old_umask new_config current_config address + [[ $(ip -all -brief address show dev "$INTERFACE") =~ ^$INTERFACE\ +\ [A-Z]+\ +(.+)$ ]] || true + new_config=$'[Interface]\n' + for address in ${BASH_REMATCH[1]}; do + new_config+="Address = $address"$'\n' + done + [[ $SAVE_CONFIG -eq 0 ]] || new_config+=$'SaveConfig = true\n' + [[ -z $PRE_UP ]] || new_config+="PreUp = $PRE_UP"$'\n' + [[ -z $POST_UP ]] || new_config+="PostUp = $POST_UP"$'\n' + [[ -z $PRE_DOWN ]] || new_config+="PreDown = $PRE_DOWN"$'\n' + [[ -z $POST_DOWN ]] || new_config+="PostDown = $POST_DOWN"$'\n' + old_umask="$(umask)" + umask 077 + current_config="$(cmd wg showconf "$INTERFACE")" + trap "rm -f '$CONFIG_FILE.tmp; exit'" INT TERM EXIT + echo "${current_config/\[Interface\]$'\n'/$new_config}" > "$CONFIG_FILE.tmp" || die "Could not write configuration file" + mv "$CONFIG_FILE.tmp" "$CONFIG_FILE" || die "Could not move configuration file" + trap - INT TERM EXIT + umask "$old_umask" +} + +execute_hook() { + [[ -n $1 ]] || return 0 + local hook="${1//%i/$INTERFACE}" + echo "[#] $hook" >&2 + (eval "$hook") +} + +cmd_usage() { + cat >&2 <<-_EOF + Usage: $PROGRAM [ up | down ] [ CONFIG_FILE | INTERFACE ] + + CONFIG_FILE is a configuration file, whose filename is the interface name + followed by \`.conf'. Otherwise, INTERFACE is an interface name, with + configuration found at /etc/wireguard/INTERFACE.conf. It is to be readable + by wg(8)'s \`setconf' sub-command, with the exception of the following additions + to the [Interface] section, which are handled by $PROGRAM: + + - Address: may be specified one or more times and contains one or more + IP addresses (with an optional CIDR mask) to be set for the interface. + - PreUp, PostUp, PreDown, PostDown: script snippets which will be executed + by bash(1) at the corresponding phases of the link, most commonly used + to configure DNS. The string \`%i' is expanded to INTERFACE. + - SaveConfig: if set to \`true', the configuration is saved from the current + state of the interface upon shutdown. + + See wg-quick(8) for more info and examples. + _EOF +} + +cmd_up() { + local i + [[ -z $(ip link show dev "$INTERFACE" 2>/dev/null) ]] || die "\`$INTERFACE' already exists" + trap 'del_if; exit' INT TERM EXIT + execute_hook "$PRE_UP" + add_if + set_config + for i in "${ADDRESSES[@]}"; do + add_addr "$i" + done + up_if + for i in $(wg show "$INTERFACE" allowed-ips | grep -Po '(?<=[\t ])[0-9.:/a-f]+' | sort -nr -k 2 -t /); do + [[ $(ip route get "$i" 2>/dev/null) == *dev\ $INTERFACE\ * ]] || add_route "$i" + done + execute_hook "$POST_UP" + trap - INT TERM EXIT +} + +cmd_down() { + [[ -n $(ip link show dev "$INTERFACE" type wireguard 2>/dev/null) ]] || die "\`$INTERFACE' is not a WireGuard interface" + execute_hook "$PRE_DOWN" + [[ $SAVE_CONFIG -eq 0 ]] || save_config + del_if + execute_hook "$POST_DOWN" +} + +if [[ $# -eq 1 && ( $1 == --help || $1 == -h || $1 == help ) ]]; then + cmd_usage +elif [[ $# -eq 2 && $1 == up ]]; then + auto_su + parse_options "$2" + cmd_up +elif [[ $# -eq 2 && $1 == down ]]; then + auto_su + parse_options "$2" + cmd_down +else + cmd_usage + exit 1 +fi + +exit 0 |