stun

commit 90fc341c2bb7ae5bacbc51986deae17fe6b383c3
parent 2d3560eed3dd059a95122ee38315e578deeef495
Author: sin <sin@2f30.org>
Date:   Tue, 22 Mar 2016 10:41:41 +0000

Set flags + mtu for linux tun

Diffstat:
M
stun.c
 | 
21
++++++++++++++++++++-

1 file changed, 20 insertions(+), 1 deletion(-)
diff --git a/stun.c b/stun.c
@@ -119,11 +119,12 @@ int
 opentun(char *tundev)
 {
 	struct ifreq ifr;
-	int ret, fd;
+	int ret, fd, s;
 
 	fd = open("/dev/net/tun", O_RDWR);
 	if (fd < 0)
 		err(1, "open %s", "/dev/net/tun");
+
 	memset(&ifr, 0, sizeof(ifr));
 	ifr.ifr_flags = IFF_TUN | IFF_NO_PI;
 	strncpy(ifr.ifr_name, tundev, IFNAMSIZ);
@@ -131,6 +132,24 @@ opentun(char *tundev)
 	ret = ioctl(fd, TUNSETIFF, &ifr);
 	if (ret < 0)
 		err(1, "ioctl: TUNSETIFF %s", tundev);
+
+	/* dummy socket so we can manipulate the params */
+	s = socket(AF_INET, SOCK_STREAM, 0);
+	if (s < 0)
+		err(1, "socket");
+	ret = ioctl(s, SIOCGIFFLAGS, &ifr);
+	if (ret < 0)
+		err(1, "ioctl: SIOCGIFFLAGS %s", tundev);
+	ifr.ifr_flags |= IFF_UP | IFF_RUNNING;
+	ret = ioctl(s, SIOCSIFFLAGS, &ifr);
+	if (ret < 0)
+		err(1, "ioctl: SIOCSIFFLAGS %s", tundev);
+	ifr.ifr_mtu = MTU;
+	ret = ioctl(s, SIOCSIFMTU, &ifr);
+	if (ret < 0)
+		err(1, "ioctl: SIOCSIFMTU %s", tundev);
+	close(s);
+
 	return fd;
 }