From: Guus Sliepen <guus@tinc-vpn.org>
Date: Sun, 1 Sep 2013 22:11:04 +0000 (+0200)
Subject: Slightly relax the connection rate limit for a single address.
X-Git-Tag: import-tinc-1.1~71
X-Git-Url: https://git.meshlink.io/?a=commitdiff_plain;h=796c14b75c9e8066b4f68f6ce7cdaddd97c46a87;p=meshlink

Slightly relax the connection rate limit for a single address.

The restriction of accepting only 1 connection per second from a single address
is a bit too much, especially if one wants to join a VPN using an invitation,
which requires two connections.
---

diff --git a/src/net_socket.c b/src/net_socket.c
index d0beb19f..ab3c17e0 100644
--- a/src/net_socket.c
+++ b/src/net_socket.c
@@ -602,10 +602,22 @@ void handle_new_meta_connection(void *data, int flags) {
 		tarpit = -1;
 	}
 
-	if(prev_time == now.tv_sec && !sockaddrcmp_noport(&sa, &prev_sa)) {
-		// if so, keep the connection open but ignore it completely.
-		tarpit = fd;
-		return;
+	if(!sockaddrcmp_noport(&sa, &prev_sa)) {
+		static int samehost_burst;
+		static int samehost_burst_time;
+
+		if(now.tv_sec - samehost_burst_time > samehost_burst)
+			samehost_burst = 0;
+		else
+			samehost_burst -= now.tv_sec - samehost_burst_time;
+
+		samehost_burst_time = now.tv_sec;
+		samehost_burst++;
+
+		if(samehost_burst > max_connection_burst) {
+			tarpit = fd;
+			return;
+		}
 	}
 
 	memcpy(&prev_sa, &sa, sizeof sa);