net/wireguard: workaround SIOCGIFSTATUS race in FreeBSD kernel

PR:		233955

net/wireguard/Makefile

@@ -2,6 +2,7 @@
 
 PORTNAME=	wireguard
 PORTVERSION=	0.0.20190406
+PORTREVISION=	1
 CATEGORIES=	net
 MASTER_SITES=	https://git.zx2c4.com/WireGuard/snapshot/
 DISTNAME=	WireGuard-${PORTVERSION}

net/wireguard/files/patch-b3e1a1b07d3631bd816f9bfc27452a89dc29fa28

@@ -0,0 +1,65 @@
+From b3e1a1b07d3631bd816f9bfc27452a89dc29fa28 Mon Sep 17 00:00:00 2001
+From: "Jason A. Donenfeld" <Jason@zx2c4.com>
+Date: Sun, 21 Apr 2019 10:11:36 +0900
+Subject: wg-quick: freebsd: workaround SIOCGIFSTATUS race in FreeBSD kernel
+
+---
+ src/tools/wg-quick/freebsd.bash | 31 ++++++++++++++++++++++---------
+ 1 file changed, 22 insertions(+), 9 deletions(-)
+
+diff --git a/src/tools/wg-quick/freebsd.bash b/src/tools/wg-quick/freebsd.bash
+index 9d3a4026..72e0bd04 100755
+--- wg-quick/freebsd.bash
++++ wg-quick/freebsd.bash
+@@ -137,18 +137,30 @@ del_routes() {
+ 	done
+ }
+ 
++if_exists() {
++	# HACK: The goal is simply to determine whether or not the interface exists. The
++	# straight-forward way of doing this would be `ifconfig $INTERFACE`, but this
++	# invokes the SIOCGIFSTATUS ioctl, which races with interface shutdown inside
++	# the tun driver, resulting in a kernel panic. So we work around it the stupid
++	# way by using the one utility that appears to call if_nametoindex fairly early
++	# and fails if it doesn't exist: `arp`.
++	if arp -i "$INTERFACE" -a -n >/dev/null 2>&1; then
++		return 0
++	else
++		return 1
++	fi
++}
++
+ del_if() {
+-	local line monitor_pid
+ 	[[ $HAVE_SET_DNS -eq 0 ]] || unset_dns
+-	exec 39< <(exec route -n monitor 2>/dev/null)
+-	monitor_pid=$!
+ 	cmd rm -f "/var/run/wireguard/$INTERFACE.sock"
+-	while ifconfig "$INTERFACE" >/dev/null 2>&1; do
+-		while read -r line; do
+-			[[ $line =~ ^RTM_IFANNOUNCE:.* ]] && break
+-		done <&39
++	while if_exists; do
++		# HACK: it would be nice to `route monitor` here and wait for RTM_IFANNOUNCE
++		# but it turns out that the announcement is made before the interface
++		# disappears so we sometimes get a hang. So, we're instead left with polling
++		# in a sleep loop like this.
++		sleep 0.1
+ 	done
+-	kill $monitor_pid
+ }
+ 
+ up_if() {
+@@ -274,7 +286,8 @@ monitor_daemon() {
+ 	# endpoints change.
+ 	while read -r event; do
+ 		[[ $event == RTM_* ]] || continue
+-		ifconfig "$INTERFACE" >/dev/null 2>&1 || break
++		[[ -e /var/run/wireguard/$INTERFACE.sock ]] || break
++		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
+-- 
+cgit v1.2.1-20-gc37e
+