Revert "wg-quick: wait on process substitutions"

This reverts commit 26683f6c9ad18d9914b23312c221f27fd5ecab51, which
means the old problem comes back. That's an issue. But waiting on
process substitutions is not available with commonly used bash versions:

  # wg-quick up demo
  [#] ip link add demo type wireguard
  [#] wg setconf demo /dev/fd/63
  /usr/bin/wg-quick: line 251: wait: pid 2955 is not a child of this shell
  [#] ip link delete dev demo

This means we have to wait a few years before fixing this issue. IOW,
bash limitation; can't fix.

Reported-by: Theodore Mozzo <theodore.mozzo@gmail.com>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

1 files changed, 11 insertions, 11 deletions

diff --git a/src/wg-quick/linux.bash b/src/wg-quick/linux.bash
index 8bda740..e4d4c4f 100755
--- 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); wait $!
+	done < <(wg show "$INTERFACE" endpoints)
 	if [[ $mtu -eq 0 ]]; then
-		read -r output < <(ip route show default) || true
+		read -r output < <(ip route show default || true) || 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) || true
-		[[ -z $nftcmd ]] || cmd nft -f <(echo -n "$nftcmd"); wait $!
+		done < <(nft list tables 2>/dev/null)
+		[[ -z $nftcmd ]] || cmd nft -f <(echo -n "$nftcmd")
 	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) || true
+			done < <($iptables-save 2>/dev/null)
 			[[ $found -ne 1 ]] || echo -n "$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"); wait $!
+	done < <(ip -o $proto addr show dev "$INTERFACE" 2>/dev/null)
 	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"); wait $!
+		cmd nft -f <(echo -n "$nftcmd")
 	else
-		echo -n "$restore" | cmd $iptables-restore -n; wait $!
+		echo -n "$restore" | cmd $iptables-restore -n
 	fi
 	HAVE_SET_FIREWALL=1
 	return 0
 }
 
 set_config() {
-	cmd wg setconf "$INTERFACE" <(echo "$WG_CONFIG"); wait $!
+	cmd wg setconf "$INTERFACE" <(echo "$WG_CONFIG")
 }
 
 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) || true
+	done < <(resolvconf -l "$(resolvconf_iface_prefix)$INTERFACE" 2>/dev/null || cat "/etc/resolvconf/run/interface/$(resolvconf_iface_prefix)$INTERFACE" 2>/dev/null)
 	[[ -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); wait $!; } | 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) | sort -nr -k 2 -t /); do
 		add_route "$i"
 	done
 	execute_hooks "${POST_UP[@]}"