static void send_udppacket(node_t *, vpn_packet_t *);
-unsigned replaywin = 16;
+unsigned replaywin = 32;
bool localdiscovery = true;
bool udp_discovery = true;
int udp_discovery_keepalive_interval = 10;
bool relay_supported = (relay->options >> 24) >= 4;
bool tcponly = (myself->options | relay->options) & OPTION_TCPONLY;
- /* Send it via TCP if it is a handshake packet, TCPOnly is in use, this is a relay packet that the other node cannot understand, or this packet is larger than the MTU.
- TODO: When relaying, the original sender does not know the end-to-end PMTU (it only knows the PMTU of the first hop).
- This can lead to scenarios where large packets are sent over UDP to relay, but then relay has no choice but fall back to TCP. */
+ /* Send it via TCP if it is a handshake packet, TCPOnly is in use, this is a relay packet that the other node cannot understand, or this packet is larger than the MTU. */
if(type == SPTPS_HANDSHAKE || tcponly || (!direct && !relay_supported) || (type != PKT_PROBE && (len - SPTPS_DATAGRAM_OVERHEAD) > relay->minmtu)) {
char buf[len * 4 / 3 + 5];
return;
}
+ /* The packet is supposed to come from the originator or its static relay
+ (i.e. with no dynamic relays in between).
+ If it did not, "help" the static relay by sending it UDP info.
+ Note that we only do this if we're the destination or the static relay;
+ otherwise every hop would initiate its own UDP info message, resulting in elevated chatter. */
+
+ if(n != from->via && to->via == myself)
+ send_udp_info(myself, from);
+
+ /* If we're not the final recipient, relay the packet. */
+
if(to != myself) {
send_sptps_data_priv(to, n, 0, DATA(&pkt), pkt.len - 2 * sizeof(node_id_t));
try_tx_sptps(n, true);
n->sock = ls - listen_socket;
if(direct && sockaddrcmp(&addr, &n->address))
update_node_udp(n, &addr);
+
+ /* If the packet went through a relay, help the sender find the appropriate MTU
+ through the relay path. */
+
+ if(!direct)
+ send_mtu_info(myself, n, MTU);
}
void handle_device_data(void *data, int flags) {