wg-quick: wait on process substitutions

Bash does not propagate error values, which is a bummer, but process substitutions are a useful feature. Introduce a new idiom to deal with this: either "; wait $!" after the line to propagate the error, or "|| true" to indicate explicitly that we don't care about the error. Signed-off-by: Jason A. Donenfeld <[email protected]>
WireGuard · Aug 6, 2020 · 26683f6 · 26683f6
1 parent 13fac76
commit 26683f6
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Showing 4 changed files with 49 additions and 49 deletions.
diff --git a/src/wg-quick/darwin.bash b/src/wg-quick/darwin.bash
@@ -92,7 +92,7 @@ detect_launchd() {
 			LAUNCHED_BY_LAUNCHD=1
 			break
 		fi
-	done < <(launchctl procinfo $$ 2>/dev/null)
+	done < <(launchctl procinfo $$ 2>/dev/null); wait $!
 }
 
 read_bool() {
@@ -132,14 +132,14 @@ del_routes() {
 	local todelete=( ) destination gateway netif
 	while read -r destination _ _ _ _ netif _; do
 		[[ $netif == "$REAL_INTERFACE" ]] && todelete+=( "$destination" )
-	done < <(netstat -nr -f inet)
+	done < <(netstat -nr -f inet); wait $!
 	for destination in "${todelete[@]}"; do
 		cmd route -q -n delete -inet "$destination" >/dev/null || true
 	done
 	todelete=( )
 	while read -r destination gateway _ netif; do
 		[[ $netif == "$REAL_INTERFACE" || ( $netif == lo* && $gateway == "$REAL_INTERFACE" ) ]] && todelete+=( "$destination" )
-	done < <(netstat -nr -f inet6)
+	done < <(netstat -nr -f inet6); wait $!
 	for destination in "${todelete[@]}"; do
 		cmd route -q -n delete -inet6 "$destination" >/dev/null || true
 	done
@@ -181,7 +181,7 @@ set_mtu() {
 			defaultif="$netif"
 			break
 		fi
-	done < <(netstat -nr -f inet)
+	done < <(netstat -nr -f inet); wait $!
 	[[ -n $defaultif && $(ifconfig "$defaultif") =~ mtu\ ([0-9]+) ]] && mtu="${BASH_REMATCH[1]}"
 	[[ $mtu -gt 0 ]] || mtu=1500
 	mtu=$(( mtu - 80 ))
@@ -197,22 +197,22 @@ collect_gateways() {
 		[[ $destination == default ]] || continue
 		GATEWAY4="$gateway"
 		break
-	done < <(netstat -nr -f inet)
+	done < <(netstat -nr -f inet); wait $!
 
 	GATEWAY6=""
 	while read -r destination gateway _; do
 		[[ $destination == default ]] || continue
 		GATEWAY6="$gateway"
 		break
-	done < <(netstat -nr -f inet6)
+	done < <(netstat -nr -f inet6); wait $!
 }
 
 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)
+	done < <(wg show "$REAL_INTERFACE" endpoints); wait $!
 }
 
 declare -A SERVICE_DNS
@@ -230,7 +230,7 @@ collect_new_service_dns() {
 		get_response="$(cmd networksetup -getsearchdomains "$service")"
 		[[ $get_response == *" "* ]] && get_response="Empty"
 		[[ -n $get_response ]] && SERVICE_DNS_SEARCH["$service"]="$get_response"
-	done; } < <(networksetup -listallnetworkservices)
+	done; } < <(networksetup -listallnetworkservices); wait $!
 
 	for service in "${!SERVICE_DNS[@]}"; do
 		if ! [[ -n ${found_services["$service"]} ]]; then
@@ -304,7 +304,7 @@ set_dns() {
 			else
 				cmd networksetup -setsearchdomains "$service" "${DNS_SEARCH[@]}"
 			fi
-		)
+		); wait $!
 	done
 }
 
@@ -316,7 +316,7 @@ del_dns() {
 		done < <(
 			cmd networksetup -setdnsservers "$service" ${SERVICE_DNS["$service"]} || true
 			cmd networksetup -setsearchdomains "$service" ${SERVICE_DNS_SEARCH["$service"]} || true
-		)
+		); wait $!
 	done
 }
 
@@ -339,7 +339,7 @@ monitor_daemon() {
 			set_dns
 			sleep 2 && kill -ALRM $pid 2>/dev/null &
 		fi
-	done < <(route -n monitor)) &
+	done < <(route -n monitor); wait $!) &
 	[[ -n $LAUNCHED_BY_LAUNCHD ]] || disown
 }
 
@@ -367,15 +367,15 @@ add_route() {
 }
 
 set_config() {
-	cmd wg setconf "$REAL_INTERFACE" <(echo "$WG_CONFIG")
+	cmd wg setconf "$REAL_INTERFACE" <(echo "$WG_CONFIG"); wait $!
 }
 
 save_config() {
 	local old_umask new_config current_config address cmd
 	new_config=$'[Interface]\n'
 	while read -r address; do
 		[[ $address =~ inet6?\ ([^ ]+) ]] && new_config+="Address = ${BASH_REMATCH[1]}"$'\n'
-	done < <(ifconfig "$REAL_INTERFACE")
+	done < <(ifconfig "$REAL_INTERFACE"); wait $!
 	# TODO: actually determine current DNS for interface
 	for address in "${DNS[@]}"; do
 		new_config+="DNS = $address"$'\n'
@@ -458,7 +458,7 @@ cmd_up() {
 	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) | sort -nr -k 2 -t /); do
+	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); wait $!; } | sort -nr -k 2 -t /); do
 		add_route "$i"
 	done
 	[[ $AUTO_ROUTE4 -eq 1 || $AUTO_ROUTE6 -eq 1 ]] && set_endpoint_direct_route

diff --git a/src/wg-quick/freebsd.bash b/src/wg-quick/freebsd.bash
@@ -121,14 +121,14 @@ del_routes() {
 	local todelete=( ) destination gateway netif
 	while read -r destination _ _ _ _ netif _; do
 		[[ $netif == "$INTERFACE" ]] && todelete+=( "$destination" )
-	done < <(netstat -nr -f inet)
+	done < <(netstat -nr -f inet); wait $!
 	for destination in "${todelete[@]}"; do
 		cmd route -q -n delete -inet "$destination" || true
 	done
 	todelete=( )
 	while read -r destination gateway _ netif; do
 		[[ $netif == "$INTERFACE" || ( $netif == lo* && $gateway == "$INTERFACE" ) ]] && todelete+=( "$destination" )
-	done < <(netstat -nr -f inet6)
+	done < <(netstat -nr -f inet6); wait $!
 	for destination in "${todelete[@]}"; do
 		cmd route -q -n delete -inet6 "$destination" || true
 	done
@@ -191,9 +191,9 @@ set_mtu() {
 		[[ ${BASH_REMATCH[1]} == *:* ]] && family=inet6
 		output="$(route -n get "-$family" "${BASH_REMATCH[1]}" || true)"
 		[[ $output =~ interface:\ ([^ ]+)$'\n' && $(ifconfig "${BASH_REMATCH[1]}") =~ mtu\ ([0-9]+) && ${BASH_REMATCH[1]} -gt $mtu ]] && mtu="${BASH_REMATCH[1]}"
-	done < <(wg show "$INTERFACE" endpoints)
+	done < <(wg show "$INTERFACE" endpoints); wait $!
 	if [[ $mtu -eq 0 ]]; then
-		read -r output < <(route -n get default || true) || true
+		read -r output < <(route -n get default) || true
 		[[ $output =~ interface:\ ([^ ]+)$'\n' && $(ifconfig "${BASH_REMATCH[1]}") =~ mtu\ ([0-9]+) && ${BASH_REMATCH[1]} -gt $mtu ]] && mtu="${BASH_REMATCH[1]}"
 	fi
 	[[ $mtu -gt 0 ]] || mtu=1500
@@ -209,22 +209,22 @@ collect_gateways() {
 		[[ $destination == default ]] || continue
 		GATEWAY4="$gateway"
 		break
-	done < <(netstat -nr -f inet)
+	done < <(netstat -nr -f inet); wait $!
 
 	GATEWAY6=""
 	while read -r destination gateway _; do
 		[[ $destination == default ]] || continue
 		GATEWAY6="$gateway"
 		break
-	done < <(netstat -nr -f inet6)
+	done < <(netstat -nr -f inet6); wait $!
 }
 
 collect_endpoints() {
 	ENDPOINTS=( )
 	while read -r _ endpoint; do
 		[[ $endpoint =~ ^\[?([a-z0-9:.]+)\]?:[0-9]+$ ]] || continue
 		ENDPOINTS+=( "${BASH_REMATCH[1]}" )
-	done < <(wg show "$INTERFACE" endpoints)
+	done < <(wg show "$INTERFACE" endpoints); wait $!
 }
 
 set_endpoint_direct_route() {
@@ -294,7 +294,7 @@ monitor_daemon() {
 		if_exists || break
 		[[ $AUTO_ROUTE4 -eq 1 || $AUTO_ROUTE6 -eq 1 ]] && set_endpoint_direct_route
 		# TODO: set the mtu as well, but only if up
-	done < <(route -n monitor)) & disown
+	done < <(route -n monitor); wait $!) & disown
 }
 
 HAVE_SET_DNS=0
@@ -335,21 +335,21 @@ add_route() {
 }
 
 set_config() {
-	cmd wg setconf "$INTERFACE" <(echo "$WG_CONFIG")
+	cmd wg setconf "$INTERFACE" <(echo "$WG_CONFIG"); wait $!
 }
 
 save_config() {
 	local old_umask new_config current_config address cmd
 	new_config=$'[Interface]\n'
 	{ read -r _; while read -r _ _ _ address _; do
 		new_config+="Address = $address"$'\n'
-	done } < <(netstat -I "$INTERFACE" -n -W -f inet)
+	done } < <(netstat -I "$INTERFACE" -n -W -f inet); wait $!
 	{ read -r _; while read -r _ _ _ address _; do
 		new_config+="Address = $address"$'\n'
-	done } < <(netstat -I "$INTERFACE" -n -W -f inet6)
+	done } < <(netstat -I "$INTERFACE" -n -W -f inet6); wait $!
 	while read -r address; do
 		[[ $address =~ ^nameserver\ ([a-zA-Z0-9_=+:%.-]+)$ ]] && new_config+="DNS = ${BASH_REMATCH[1]}"$'\n'
-	done < <(resolvconf -l "$INTERFACE" 2>/dev/null)
+	done < <(resolvconf -l "$INTERFACE" 2>/dev/null); wait $!
 	[[ -n $MTU ]] && new_config+="MTU = $MTU"$'\n'
 	[[ -n $TABLE ]] && new_config+="Table = $TABLE"$'\n'
 	[[ $SAVE_CONFIG -eq 0 ]] || new_config+=$'SaveConfig = true\n'
@@ -427,7 +427,7 @@ cmd_up() {
 	set_mtu
 	up_if
 	set_dns
-	for i in $(while read -r _ i; do for i in $i; do [[ $i =~ ^[0-9a-z:.]+/[0-9]+$ ]] && echo "$i"; done; done < <(wg show "$INTERFACE" allowed-ips) | sort -nr -k 2 -t /); do
+	for i in $({ while read -r _ i; do for i in $i; do [[ $i =~ ^[0-9a-z:.]+/[0-9]+$ ]] && echo "$i"; done; done < <(wg show "$INTERFACE" allowed-ips); wait $!; } | sort -nr -k 2 -t /); do
 		add_route "$i"
 	done
 	[[ $AUTO_ROUTE4 -eq 1 || $AUTO_ROUTE6 -eq 1 ]] && set_endpoint_direct_route

diff --git a/src/wg-quick/linux.bash b/src/wg-quick/linux.bash
@@ -132,9 +132,9 @@ set_mtu_up() {
 		[[ $endpoint =~ ^\[?([a-z0-9:.]+)\]?:[0-9]+$ ]] || continue
 		output="$(ip route get "${BASH_REMATCH[1]}" || true)"
 		[[ ( $output =~ mtu\ ([0-9]+) || ( $output =~ dev\ ([^ ]+) && $(ip link show dev "${BASH_REMATCH[1]}") =~ mtu\ ([0-9]+) ) ) && ${BASH_REMATCH[1]} -gt $mtu ]] && mtu="${BASH_REMATCH[1]}"
-	done < <(wg show "$INTERFACE" endpoints)
+	done < <(wg show "$INTERFACE" endpoints); wait $!
 	if [[ $mtu -eq 0 ]]; then
-		read -r output < <(ip route show default || true) || true
+		read -r output < <(ip route show default) || true
 		[[ ( $output =~ mtu\ ([0-9]+) || ( $output =~ dev\ ([^ ]+) && $(ip link show dev "${BASH_REMATCH[1]}") =~ mtu\ ([0-9]+) ) ) && ${BASH_REMATCH[1]} -gt $mtu ]] && mtu="${BASH_REMATCH[1]}"
 	fi
 	[[ $mtu -gt 0 ]] || mtu=1500
@@ -191,8 +191,8 @@ remove_firewall() {
 		local table nftcmd
 		while read -r table; do
 			[[ $table == *" wg-quick-$INTERFACE" ]] && printf -v nftcmd '%sdelete %s\n' "$nftcmd" "$table"
-		done < <(nft list tables 2>/dev/null)
-		[[ -z $nftcmd ]] || cmd nft -f <(echo -n "$nftcmd")
+		done < <(nft list tables 2>/dev/null) || true
+		[[ -z $nftcmd ]] || cmd nft -f <(echo -n "$nftcmd"); wait $!
 	fi
 	if type -p iptables >/dev/null; then
 		local line iptables found restore
@@ -202,7 +202,7 @@ remove_firewall() {
 				[[ $line == "*"* || $line == COMMIT || $line == "-A "*"-m comment --comment \"wg-quick(8) rule for $INTERFACE\""* ]] || continue
 				[[ $line == "-A"* ]] && found=1
 				printf -v restore '%s%s\n' "$restore" "${line/#-A/-D}"
-			done < <($iptables-save 2>/dev/null)
+			done < <($iptables-save 2>/dev/null) || true
 			[[ $found -ne 1 ]] || echo -n "$restore" | cmd $iptables-restore -n
 		done
 	fi
@@ -233,22 +233,22 @@ add_default() {
 		[[ $line =~ .*inet6?\ ([0-9a-f:.]+)/[0-9]+.* ]] || continue
 		printf -v restore '%s-I PREROUTING ! -i %s -d %s -m addrtype ! --src-type LOCAL -j DROP %s\n' "$restore" "$INTERFACE" "${BASH_REMATCH[1]}" "$marker"
 		printf -v nftcmd '%sadd rule %s %s preraw iifname != "%s" %s daddr %s fib saddr type != local drop\n' "$nftcmd" "$pf" "$nftable" "$INTERFACE" "$pf" "${BASH_REMATCH[1]}"
-	done < <(ip -o $proto addr show dev "$INTERFACE" 2>/dev/null)
+	done < <(ip -o $proto addr show dev "$INTERFACE"); wait $!
 	printf -v restore '%sCOMMIT\n*mangle\n-I POSTROUTING -m mark --mark %d -p udp -j CONNMARK --save-mark %s\n-I PREROUTING -p udp -j CONNMARK --restore-mark %s\nCOMMIT\n' "$restore" $table "$marker" "$marker"
 	printf -v nftcmd '%sadd rule %s %s postmangle meta l4proto udp mark %d ct mark set mark \n' "$nftcmd" "$pf" "$nftable" $table
 	printf -v nftcmd '%sadd rule %s %s premangle meta l4proto udp meta mark set ct mark \n' "$nftcmd" "$pf" "$nftable"
 	[[ $proto == -4 ]] && cmd sysctl -q net.ipv4.conf.all.src_valid_mark=1
 	if type -p nft >/dev/null; then
-		cmd nft -f <(echo -n "$nftcmd")
+		cmd nft -f <(echo -n "$nftcmd"); wait $!
 	else
-		echo -n "$restore" | cmd $iptables-restore -n
+		echo -n "$restore" | cmd $iptables-restore -n; wait $!
 	fi
 	HAVE_SET_FIREWALL=1
 	return 0
 }
 
 set_config() {
-	cmd wg setconf "$INTERFACE" <(echo "$WG_CONFIG")
+	cmd wg setconf "$INTERFACE" <(echo "$WG_CONFIG"); wait $!
 }
 
 save_config() {
@@ -260,7 +260,7 @@ save_config() {
 	done
 	while read -r address; do
 		[[ $address =~ ^nameserver\ ([a-zA-Z0-9_=+:%.-]+)$ ]] && new_config+="DNS = ${BASH_REMATCH[1]}"$'\n'
-	done < <(resolvconf -l "$(resolvconf_iface_prefix)$INTERFACE" 2>/dev/null || cat "/etc/resolvconf/run/interface/$(resolvconf_iface_prefix)$INTERFACE" 2>/dev/null)
+	done < <(resolvconf -l "$(resolvconf_iface_prefix)$INTERFACE" 2>/dev/null || cat "/etc/resolvconf/run/interface/$(resolvconf_iface_prefix)$INTERFACE" 2>/dev/null) || true
 	[[ -n $MTU && $(ip link show dev "$INTERFACE") =~ mtu\ ([0-9]+) ]] && new_config+="MTU = ${BASH_REMATCH[1]}"$'\n'
 	[[ -n $TABLE ]] && new_config+="Table = $TABLE"$'\n'
 	[[ $SAVE_CONFIG -eq 0 ]] || new_config+=$'SaveConfig = true\n'
@@ -335,7 +335,7 @@ cmd_up() {
 	done
 	set_mtu_up
 	set_dns
-	for i in $(while read -r _ i; do for i in $i; do [[ $i =~ ^[0-9a-z:.]+/[0-9]+$ ]] && echo "$i"; done; done < <(wg show "$INTERFACE" allowed-ips) | sort -nr -k 2 -t /); do
+	for i in $({ while read -r _ i; do for i in $i; do [[ $i =~ ^[0-9a-z:.]+/[0-9]+$ ]] && echo "$i"; done; done < <(wg show "$INTERFACE" allowed-ips); wait $!; } | sort -nr -k 2 -t /); do
 		add_route "$i"
 	done
 	execute_hooks "${POST_UP[@]}"

diff --git a/src/wg-quick/openbsd.bash b/src/wg-quick/openbsd.bash
@@ -131,14 +131,14 @@ del_routes() {
 	[[ -n $REAL_INTERFACE ]] || return 0
 	while read -r destination _ _ _ _ netif _; do
 		[[ $netif == "$REAL_INTERFACE" ]] && todelete+=( "$destination" )
-	done < <(netstat -nr -f inet)
+	done < <(netstat -nr -f inet); wait $!
 	for destination in "${todelete[@]}"; do
 		cmd route -q -n delete -inet "$destination" || true
 	done
 	todelete=( )
 	while read -r destination gateway _ netif; do
 		[[ $netif == "$REAL_INTERFACE" || ( $netif == lo* && $gateway == "$REAL_INTERFACE" ) ]] && todelete+=( "$destination" )
-	done < <(netstat -nr -f inet6)
+	done < <(netstat -nr -f inet6); wait $!
 	for destination in "${todelete[@]}"; do
 		cmd route -q -n delete -inet6 "$destination" || true
 	done
@@ -189,9 +189,9 @@ set_mtu() {
 		[[ ${BASH_REMATCH[1]} == *:* ]] && family=inet6
 		output="$(route -n get "-$family" "${BASH_REMATCH[1]}" || true)"
 		[[ $output =~ interface:\ ([^ ]+)$'\n' && $(ifconfig "${BASH_REMATCH[1]}") =~ mtu\ ([0-9]+) && ${BASH_REMATCH[1]} -gt $mtu ]] && mtu="${BASH_REMATCH[1]}"
-	done < <(wg show "$REAL_INTERFACE" endpoints)
+	done < <(wg show "$REAL_INTERFACE" endpoints); wait $!
 	if [[ $mtu -eq 0 ]]; then
-		read -r output < <(route -n get default || true) || true
+		read -r output < <(route -n get default) || true
 		[[ $output =~ interface:\ ([^ ]+)$'\n' && $(ifconfig "${BASH_REMATCH[1]}") =~ mtu\ ([0-9]+) && ${BASH_REMATCH[1]} -gt $mtu ]] && mtu="${BASH_REMATCH[1]}"
 	fi
 	[[ $mtu -gt 0 ]] || mtu=1500
@@ -207,22 +207,22 @@ collect_gateways() {
 		[[ $destination == default ]] || continue
 		GATEWAY4="$gateway"
 		break
-	done < <(netstat -nr -f inet)
+	done < <(netstat -nr -f inet); wait $!
 
 	GATEWAY6=""
 	while read -r destination gateway _; do
 		[[ $destination == default ]] || continue
 		GATEWAY6="$gateway"
 		break
-	done < <(netstat -nr -f inet6)
+	done < <(netstat -nr -f inet6); wait $!
 }
 
 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)
+	done < <(wg show "$REAL_INTERFACE" endpoints); wait $!
 }
 
 set_endpoint_direct_route() {
@@ -290,7 +290,7 @@ monitor_daemon() {
 		ifconfig "$REAL_INTERFACE" >/dev/null 2>&1 || break
 		[[ $AUTO_ROUTE4 -eq 1 || $AUTO_ROUTE6 -eq 1 ]] && set_endpoint_direct_route
 		# TODO: set the mtu as well, but only if up
-	done < <(route -n monitor)) & disown
+	done < <(route -n monitor); wait $!) & disown
 }
 
 set_dns() {
@@ -339,15 +339,15 @@ add_route() {
 }
 
 set_config() {
-	cmd wg setconf "$REAL_INTERFACE" <(echo "$WG_CONFIG")
+	cmd wg setconf "$REAL_INTERFACE" <(echo "$WG_CONFIG"); wait $!
 }
 
 save_config() {
 	local old_umask new_config current_config address network cmd
 	new_config=$'[Interface]\n'
 	{ read -r _; while read -r _ _ network address _; do
 		[[ $network == *Link* ]] || new_config+="Address = $address"$'\n'
-	done } < <(netstat -I "$REAL_INTERFACE" -n -v)
+	done } < <(netstat -I "$REAL_INTERFACE" -n -v); wait $!
 	# TODO: actually determine current DNS for interface
 	for address in "${DNS[@]}"; do
 		new_config+="DNS = $address"$'\n'
@@ -428,7 +428,7 @@ cmd_up() {
 	set_mtu
 	up_if
 	set_dns
-	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) | sort -nr -k 2 -t /); do
+	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); wait $!; } | sort -nr -k 2 -t /); do
 		add_route "$i"
 	done
 	[[ $AUTO_ROUTE4 -eq 1 || $AUTO_ROUTE6 -eq 1 ]] && set_endpoint_direct_route