X-Git-Url: https://www.tinc-vpn.org/git/browse?a=blobdiff_plain;f=src%2Fnet_packet.c;h=1e455434be6f48382bbe776bf46734f388027c71;hb=61275547cdf950e1c4499f19044ff171a9a74af7;hp=c0be8c4de2f074538041c03d89639025403e0927;hpb=eef25266cb862b5e2c24450d158d99e3cb43e511;p=tinc

diff --git a/src/net_packet.c b/src/net_packet.c
index c0be8c4d..1e455434 100644
--- a/src/net_packet.c
+++ b/src/net_packet.c
@@ -150,6 +150,21 @@ static void send_mtu_probe_handler(void *data) {
 		send_udppacket(n, &packet);
 	}
 
+	n->probe_counter = 0;
+	gettimeofday(&n->probe_time, NULL);
+
+	/* Calculate the packet loss of incoming traffic by comparing the rate of
+	   packets received to the rate with which the sequence number has increased.
+	 */
+
+	if(n->received > n->prev_received)
+		n->packetloss = 1.0 - (n->received - n->prev_received) / (float)(n->received_seqno - n->prev_received_seqno);
+	else
+		n->packetloss = n->received_seqno <= n->prev_received_seqno;
+
+	n->prev_received_seqno = n->received_seqno;
+	n->prev_received = n->received;
+
 end:
 	timeout_set(&n->mtutimeout, &(struct timeval){timeout, rand() % 100000});
 }
@@ -196,6 +211,25 @@ static void mtu_probe_h(node_t *n, vpn_packet_t *packet, length_t len) {
 			len = n->maxmtu;
 		if(n->minmtu < len)
 			n->minmtu = len;
+
+		/* Calculate RTT and bandwidth.
+		   The RTT is the time between the MTU probe burst was sent and the first
+		   reply is received. The bandwidth is measured using the time between the
+		   arrival of the first and third probe reply.
+		 */
+
+		struct timeval now, diff;
+		gettimeofday(&now, NULL);
+		timersub(&now, &n->probe_time, &diff);
+		n->probe_counter++;
+
+		if(n->probe_counter == 1) {
+			n->rtt = diff.tv_sec + diff.tv_usec * 1e-6;
+			n->probe_time = now;
+		} else if(n->probe_counter == 3) {
+			n->bandwidth = 2.0 * len / (diff.tv_sec + diff.tv_usec * 1e-6);
+			logger(DEBUG_TRAFFIC, LOG_DEBUG, "%s (%s) RTT %.2f ms, burst bandwidth %.3f Mbit/s, rx packet loss %.2f %%", n->name, n->hostname, n->rtt * 1e3, n->bandwidth * 8e-6, n->packetloss * 1e2);
+		}
 	}
 }