From a5412d10562840a079b955dae4cfb334ae22daf4 Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Date: Mon, 14 May 2018 22:28:53 +0200 Subject: [PATCH] wg-quick: add darwin implementation It's pretty rough and leaves much to be desired, but it works. Signed-off-by: Jason A. Donenfeld --- src/wg-quick/darwin.bash | 444 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 444 insertions(+) create mode 100755 src/wg-quick/darwin.bash diff --git a/src/wg-quick/darwin.bash b/src/wg-quick/darwin.bash new file mode 100755 index 0000000..c4fc8f1 --- /dev/null +++ b/src/wg-quick/darwin.bash @@ -0,0 +1,444 @@ +#!/usr/local/bin/bash +# SPDX-License-Identifier: GPL-2.0 +# +# Copyright (C) 2015-2018 Jason A. Donenfeld . All Rights Reserved. +# + +# The shebang is in /usr/local because this requires bash 4. + +set -e -o pipefail +shopt -s extglob +export LC_ALL=C + +SELF="${BASH_SOURCE[0]}" +SELF="$(cd "${SELF%/*}" && pwd -P)/${SELF##*/}" +export PATH="${SELF%/*}:$PATH" + +WG_CONFIG="" +INTERFACE="" +ADDRESSES=( ) +MTU="" +DNS=( ) +TABLE="" +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 stripped + CONFIG_FILE="$1" + [[ $CONFIG_FILE =~ ^[a-zA-Z0-9_=+.-]{1,15}$ ]] && CONFIG_FILE="/etc/wireguard/$CONFIG_FILE.conf" + [[ -e $CONFIG_FILE ]] || die "\`$CONFIG_FILE' does not exist" + [[ $CONFIG_FILE =~ (^|/)([a-zA-Z0-9_=+.-]{1,15})\.conf$ ]] || die "The config file must be a valid interface name, followed by .conf" + CONFIG_FILE="$(cd "${CONFIG_FILE%/*}" && pwd -P)/${CONFIG_FILE##*/}" + ((($(stat -f '0%#p' "$CONFIG_FILE") & $(stat -f '0%#p' "${CONFIG_FILE%/*}") & 0007) == 0)) || echo "Warning: \`$CONFIG_FILE' is world accessible" >&2 + INTERFACE="${BASH_REMATCH[2]}" + shopt -s nocasematch + while read -r line || [[ -n $line ]]; do + stripped="${line%%\#*}" + key="${stripped%%=*}"; key="${key##*([[:space:]])}"; key="${key%%*([[:space:]])}" + value="${stripped#*=}"; value="${value##*([[:space:]])}"; value="${value%%*([[:space:]])}" + [[ $key == "["* ]] && interface_section=0 + [[ $key == "[Interface]" ]] && interface_section=1 + if [[ $interface_section -eq 1 ]]; then + case "$key" in + Address) ADDRESSES+=( ${value//,/ } ); continue ;; + MTU) MTU="$value"; continue ;; + DNS) DNS+=( ${value//,/ } ); continue ;; + Table) TABLE="$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() { + case "$2" in + true) printf -v "$1" 1 ;; + false) printf -v "$1" 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[@]}" +} + +get_real_interface() { + local interface diff + wg show interfaces >/dev/null + [[ -f "/var/run/wireguard/$INTERFACE.name" ]] || return 1 + interface="$(< "/var/run/wireguard/$INTERFACE.name")" + [[ -n $interface && -S "/var/run/wireguard/$interface.sock" ]] || return 1 + diff=$(( $(stat -f %m "/var/run/wireguard/$interface.sock" 2>/dev/null || echo 200) - $(stat -f %m "/var/run/wireguard/$INTERFACE.name" 2>/dev/null || echo 100) )) + [[ $diff -ge 2 || $diff -le -2 ]] && return 1 + REAL_INTERFACE="$interface" + echo "[+] Interface for $INTERFACE is $REAL_INTERFACE" >&2 + return 0 +} + +add_if() { + export WG_DARWIN_UTUN_NAME_FILE="/var/run/wireguard/$INTERFACE.name" + cmd wireguard-go utun + local i + for i in {1..30}; do + [[ -f "/var/run/wireguard/$INTERFACE.name" ]] && break + sleep 0.1 + done + get_real_interface +} + +del_routes() { + local todelete=( ) destination netif + while read -r destination _ _ _ _ netif _; do + [[ $netif == "$REAL_INTERFACE" ]] && todelete+=( "$destination" ) + done < <(netstat -nr -f inet) + for destination in "${todelete[@]}"; do + cmd route -q delete -inet "$destination" >/dev/null || true + done + todelete=( ) + while read -r destination _ _ netif; do + [[ $netif == "$REAL_INTERFACE" ]] && todelete+=( "$destination" ) + done < <(netstat -nr -f inet6) + for destination in "${todelete[@]}"; do + cmd route -q delete -inet6 "$destination" >/dev/null || true + done + for destination in "${ENDPOINTS[@]}"; do + if [[ $destination == *:* ]]; then + cmd route -q delete -inet6 "$destination" >/dev/null || true + else + cmd route -q delete -inet "$destination" >/dev/null || true + fi + done +} + +del_if() { + [[ -z $REAL_INTERFACE ]] || cmd rm -f "/var/run/wireguard/$REAL_INTERFACE.sock" + cmd rm -f "/var/run/wireguard/$INTERFACE.name" +} + +up_if() { + cmd ifconfig "$REAL_INTERFACE" up +} + +add_addr() { + if [[ $1 == *:* ]]; then + cmd ifconfig "$REAL_INTERFACE" inet6 "$1" + else + cmd ifconfig "$REAL_INTERFACE" inet "$1" "${1%%/*}" + fi +} + +set_mtu() { + local mtu=0 current_mtu=-1 destination netif defaultif + if [[ -n $MTU ]]; then + cmd ifconfig "$REAL_INTERFACE" mtu "$MTU" + return + fi + while read -r destination _ _ _ _ netif _; do + if [[ $destination == default ]]; then + defaultif="$netif" + break + fi + done < <(netstat -nr -f inet) + [[ -n $defaultif && $(ifconfig "$defaultif") =~ mtu\ ([0-9]+) ]] && mtu="${BASH_REMATCH[1]}" + [[ $mtu -gt 0 ]] || mtu=1500 + mtu=$(( mtu - 80 )) + [[ $(ifconfig "$REAL_INTERFACE") =~ mtu\ ([0-9]+) ]] && current_mtu="${BASH_REMATCH[1]}" + [[ $mtu -eq $current_mtu ]] || cmd ifconfig "$REAL_INTERFACE" mtu "$mtu" +} + +collect_gateways() { + local destination gateway + + GATEWAY4="" + while read -r destination gateway _; do + [[ $destination == default ]] || continue + GATEWAY4="$gateway" + break + done < <(netstat -nr -f inet) + + GATEWAY6="" + while read -r destination gateway _; do + [[ $destination == default ]] || continue + [[ $gateway == fe80:* ]] && continue + GATEWAY6="$gateway" + break + done < <(netstat -nr -f inet6) +} + +collect_endpoints() { + ENDPOINTS=( ) + while read -r _ endpoint; do + [[ $endpoint =~ ^\[?([a-z0-9:.]+)\]?:[0-9]+$ ]] || continue + ENDPOINTS+=( "${BASH_REMATCH[1]}" ) + done < <(wg show "$REAL_INTERFACE" endpoints) +} + +set_endpoint_direct_route() { + local old_endpoints endpoint old_gateway4 old_gateway6 remove_all_old=0 added=( ) + old_endpoints=( "${ENDPOINTS[@]}" ) + old_gateway4="$GATEWAY4" + old_gateway6="$GATEWAY6" + collect_gateways + collect_endpoints + + [[ $old_gateway4 != "$GATEWAY4" || $old_gateway6 != "$GATEWAY6" ]] && remove_all_old=1 + + if [[ $remove_all_old -eq 1 ]]; then + for endpoint in "${ENDPOINTS[@]}"; do + [[ " ${old_endpoints[*]} " == *"$endpoint"* ]] || old_endpoints+=( "$endpoint" ) + done + fi + + for endpoint in "${old_endpoints[@]}"; do + [[ $remove_all_old -eq 0 && " ${ENDPOINTS[*]} " == *"$endpoint"* ]] && continue + if [[ $endpoint == *:* ]]; then + cmd route -q delete -inet6 "$endpoint" >/dev/null 2>&1 || true + else + cmd route -q delete -inet "$endpoint" >/dev/null 2>&1 || true + fi + done + + for endpoint in "${ENDPOINTS[@]}"; do + if [[ $remove_all_old -eq 0 && " ${old_endpoints[*]} " == *"$endpoint"* ]]; then + added+=( "$endpoint" ) + continue + fi + if [[ $endpoint == *:* && -n $GATEWAY6 ]]; then + cmd route -q add -inet6 "$endpoint" -gateway "$GATEWAY6" >/dev/null || true + added+=( "$endpoint" ) + elif [[ -n $GATEWAY4 ]]; then + cmd route -q add -inet "$endpoint" -gateway "$GATEWAY4" >/dev/null || true + added+=( "$endpoint" ) + fi + done + ENDPOINTS=( "${added[@]}" ) +} + +set_dns() { + # TODO: this should use scutil and be slightly more clever. But for now + # we simply overwrite any _manually set_ DNS servers for all network + # services. This means we get into trouble if the user doesn't actually + # want DNS via DHCP when setting this back to "empty". Because macOS is + # so horrible to deal with here, we'll simply wait for irate users to + # provide a patch themselves. + + local service response + + { read -r _; while read -r service; do + [[ $service == "*"* ]] && service="${service:1}" + while read -r response; do + [[ $response == *Error* ]] && echo "$response" >&2 + done < <(cmd networksetup -setdnsservers "$service" "${DNS[@]}") + done; } < <(networksetup -listallnetworkservices) +} + +del_dns() { + { read -r _; while read -r service; do + [[ $service == "*"* ]] && service="${service:1}" + while read -r response; do + [[ $response == *Error* ]] && echo "$response" >&2 + done < <(cmd networksetup -setdnsservers "$service" Empty) + done; } < <(networksetup -listallnetworkservices) +} + +monitor_daemon() { + echo "[+] Backgrounding route monitor" >&2 + (trap 'del_routes; del_dns; exit 0' INT TERM EXIT + exec 1>&- 2>&- + local event + # TODO: this should also check to see if the endpoint actually changes + # in response to incoming packets, and then call set_endpoint_direct_route + # then too. That function should be able to gracefully cleanup if the + # endpoints change. + while read -r event; do + [[ $event == RTM_* ]] || continue + ifconfig "$REAL_INTERFACE" >/dev/null 2>&1 || break + [[ $AUTO_ROUTE4 -eq 1 || $AUTO_ROUTE6 -eq 1 ]] && set_endpoint_direct_route + [[ -z $MTU ]] && set_mtu + [[ ${#DNS[@]} -gt 0 ]] && set_dns + done < <(route -n monitor)) & disown +} + +add_route() { + [[ $TABLE != off ]] || return 0 + + local family=inet + [[ $1 == *:* ]] && family=inet6 + + if [[ $1 == */0 && ( -z $TABLE || $TABLE == auto ) ]]; then + if [[ $1 == *:* ]]; then + AUTO_ROUTE6=1 + cmd route -q add -inet6 ::/1 -interface "$REAL_INTERFACE" >/dev/null + cmd route -q add -inet6 8000::/1 -interface "$REAL_INTERFACE" >/dev/null + else + AUTO_ROUTE4=1 + cmd route -q add -inet 0.0.0.0/1 -interface "$REAL_INTERFACE" >/dev/null + cmd route -q add -inet 128.0.0.0/1 -interface "$REAL_INTERFACE" >/dev/null + fi + else + [[ $TABLE == main || $TABLE == auto || -z $TABLE ]] || die "Darwin only supports TABLE=auto|main|off" + cmd route -q add "-$family" "$1" -interface "$REAL_INTERFACE" >/dev/null + fi +} + +set_config() { + cmd wg setconf "$REAL_INTERFACE" <(echo "$WG_CONFIG") +} + +save_config() { + local old_umask new_config current_config address cmd + new_config=$'[Interface]\n' + for address in "${ADDRESSES[@]}"; do + new_config+="Address = $address"$'\n' + done + for address in "${DNS[@]}"; do + new_config+="DNS = $address"$'\n' + done + [[ -n $MTU ]] && new_config+="MTU = $MTU"$'\n' + [[ -n $TABLE ]] && new_config+="Table = $TABLE"$'\n' + [[ $SAVE_CONFIG -eq 0 ]] || new_config+=$'SaveConfig = true\n' + for cmd in "${PRE_UP[@]}"; do + new_config+="PreUp = $cmd"$'\n' + done + for cmd in "${POST_UP[@]}"; do + new_config+="PostUp = $cmd"$'\n' + done + for cmd in "${PRE_DOWN[@]}"; do + new_config+="PreDown = $cmd"$'\n' + done + for cmd in "${POST_DOWN[@]}"; do + new_config+="PostDown = $cmd"$'\n' + done + old_umask="$(umask)" + umask 077 + current_config="$(cmd wg showconf "$REAL_INTERFACE")" + trap 'rm -f "$CONFIG_FILE.tmp"; exit' INT TERM EXIT + echo "${current_config/\[Interface\]$'\n'/$new_config}" > "$CONFIG_FILE.tmp" || die "Could not write configuration file" + sync "$CONFIG_FILE.tmp" + mv "$CONFIG_FILE.tmp" "$CONFIG_FILE" || die "Could not move configuration file" + trap - INT TERM EXIT + umask "$old_umask" +} + +execute_hooks() { + local hook + for hook in "$@"; do + hook="${hook//%i/$REAL_INTERFACE}" + hook="${hook//%I/$INTERFACE}" + echo "[#] $hook" >&2 + (eval "$hook") + done +} + +cmd_usage() { + cat >&2 <<-_EOF + Usage: $PROGRAM [ up | down | save ] [ 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 $PROGRAM: + + - Address: may be specified one or more times and contains one or more + IP addresses (with an optional CIDR mask) to be set for the interface. + - DNS: an optional DNS server to use while the device is up. + - MTU: an optional MTU for the interface; if unspecified, auto-calculated. + - Table: an optional routing table to which routes will be added; if + unspecified or \`auto', the default table is used. If \`off', no routes + are added. Besides \`auto' and \`off', only \`main' is supported on + this platform. + - PreUp, PostUp, PreDown, PostDown: script snippets which will be executed + by bash(1) at the corresponding phases of the link, most commonly used + to configure DNS. The string \`%i' is expanded to INTERFACE. + - SaveConfig: if set to \`true', the configuration is saved from the current + state of the interface upon shutdown. + + See wg-quick(8) for more info and examples. + _EOF +} + +cmd_up() { + local i + get_real_interface && die "\`$INTERFACE' already exists as \`$REAL_INTERFACE'" + trap 'del_if; del_routes; exit' INT TERM EXIT + execute_hooks "${PRE_UP[@]}" + add_if + set_config + for i in "${ADDRESSES[@]}"; do + add_addr "$i" + done + set_mtu + up_if + for i in $(while read -r _ i; do for i in $i; do [[ $i =~ ^[0-9a-z:.]+/[0-9]+$ ]] && echo "$i"; done; done < <(wg show "$REAL_INTERFACE" allowed-ips)); do + add_route "$i" + done + [[ $AUTO_ROUTE4 -eq 1 || $AUTO_ROUTE6 -eq 1 ]] && set_endpoint_direct_route + [[ ${#DNS[@]} -gt 0 ]] && set_dns + monitor_daemon + execute_hooks "${POST_UP[@]}" + trap - INT TERM EXIT +} + +cmd_down() { + if ! get_real_interface || [[ " $(wg show interfaces) " != *" $REAL_INTERFACE "* ]]; then + die "\`$INTERFACE' is not a WireGuard interface" + fi + execute_hooks "${PRE_DOWN[@]}" + [[ $SAVE_CONFIG -eq 0 ]] || save_config + del_if + execute_hooks "${POST_DOWN[@]}" +} + +cmd_save() { + if ! get_real_interface || [[ " $(wg show interfaces) " != *" $REAL_INTERFACE "* ]]; then + die "\`$INTERFACE' is not a WireGuard interface" + fi + save_config +} + +# ~~ function override insertion point ~~ + +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 +elif [[ $# -eq 2 && $1 == save ]]; then + auto_su + parse_options "$2" + cmd_save +else + cmd_usage + exit 1 +fi + +exit 0