[PATCH] ppp: change MTU on TUN device when MRU option received

[Kristen Carlson Accardi]

---
 gatchat/ppp_net.c |   16 ++++++++++++++++
 1 files changed, 16 insertions(+), 0 deletions(-)

diff --git a/gatchat/ppp_net.c b/gatchat/ppp_net.c
index c1f2eb4..fc1f9fb 100644
--- a/gatchat/ppp_net.c
+++ b/gatchat/ppp_net.c
@@ -50,10 +50,26 @@ struct ppp_net {
 
 void ppp_net_set_mtu(struct ppp_net *net, guint16 mtu)
 {
+	struct ifreq ifr;
+	int sock;
+
 	if (net == NULL)
 		return;
 
 	net->mtu = mtu;
+
+	sock = socket(AF_INET, SOCK_DGRAM, 0);
+	if (sock < 0)
+		return;
+
+	memset(&ifr, 0, sizeof(ifr));
+
+	strncpy(ifr.ifr_name, net->if_name, sizeof(ifr.ifr_name));
+	ifr.ifr_mtu = mtu;
+	if (ioctl(sock, SIOCSIFMTU, (caddr_t) &ifr) < 0)
+		g_printerr("Unable to change MTU\n");
+
+	close(sock);
 }
 
 void ppp_net_process_packet(struct ppp_net *net, guint8 *packet)
-- 
1.6.6.1