wg-quick: freebsd: allow loopback to work

FreeBSD adds a route for point-to-point destination addresses. We don't
really want to specify any destination address, but unfortunately we
have to. Before we tried to cheat by giving our own address as the
destination, but this had the unfortunate effect of preventing
loopback from working on our local ip address. We work around this with
yet another kludge: we set the destination address to 127.0.0.1. Since
127.0.0.1 is already assigned to an interface, this has the same effect
of not specifying a destination address, and therefore we accomplish the
intended behavior.

Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

src/wg-quick/freebsd.bash

@@ -158,7 +158,7 @@ add_addr() {
 	if [[ $1 == *:* ]]; then
 		cmd ifconfig "$INTERFACE" inet6 "$1" alias
 	else
-		cmd ifconfig "$INTERFACE" inet "$1" "${1%%/*}" alias
+		cmd ifconfig "$INTERFACE" inet "$1" 127.0.0.1 alias
 	fi
 }