From: Etienne Dechamps <etienne@edechamps.fr>
Date: Sun, 8 Mar 2015 14:32:01 +0000 (+0000)
Subject: Fix UDP/MTU discovery in intermediate SPTPS UDP relays.
X-Git-Tag: release-1.1pre12~198
X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=c23e50385d9de538af676706596f6508b2ceb01a;p=oweals%2Ftinc.git

Fix UDP/MTU discovery in intermediate SPTPS UDP relays.

Refactoring commit 81578484dc74fd92f1b01f71f882016f120ab1de seems to
have introduced a regression as it moved discovery code away from
send_sptps_data_priv() and within send_packet(). The issue is,
send_packet() is not called when the node is simply relaying an UDP
SPTPS packet: indeed, send_sptps_data_priv() is called directly from
handle_incoming_vpn_data() in that case.

As a result, try_tx_sptps() is not called in the relaying case, which in
practice means that a relay doesn't initiate UDP/MTU discovery with the
next relay (unless some other activity compels it to do so). This can
result in packets getting sent over TCP instead of UDP from the relay.
---

diff --git a/src/net_packet.c b/src/net_packet.c
index df87e27..8dba325 100644
--- a/src/net_packet.c
+++ b/src/net_packet.c
@@ -1396,6 +1396,7 @@ skip_harder:
 
 		if(to != myself) {
 			send_sptps_data_priv(to, n, 0, DATA(&pkt), pkt.len - 2 * sizeof(node_id_t));
+			try_tx_sptps(n, true);
 			return;
 		}
 	} else {