From e120e9a78eb9eba3914f4e28e90006705c82703e Mon Sep 17 00:00:00 2001
From: orignal <i2porignal@yandex.ru>
Date: Wed, 20 Apr 2016 14:53:50 -0400
Subject: [PATCH] configurable transit tunnels limit

---
 Config.cpp       |  1 +
 Daemon.cpp       |  2 ++
 I2NPProtocol.cpp | 12 +++++++++++-
 I2NPProtocol.h   |  5 +++--
 4 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/Config.cpp b/Config.cpp
index 922ce236..d7cef879 100644
--- a/Config.cpp
+++ b/Config.cpp
@@ -198,6 +198,7 @@ namespace config {
 	  
     m_OptionsDesc
       .add(general)
+	  .add(limits)	
       .add(httpserver)
       .add(httpproxy)
       .add(socksproxy)
diff --git a/Daemon.cpp b/Daemon.cpp
index 0924b236..81bbcdd5 100644
--- a/Daemon.cpp
+++ b/Daemon.cpp
@@ -141,6 +141,8 @@ namespace i2p
 			i2p::context.SetSupportsV6		 (ipv6);
 			i2p::context.SetSupportsV4		 (ipv4);
 			i2p::context.SetAcceptsTunnels (!transit);
+			uint16_t transitTunnels; i2p::config::GetOption("limits.transittunnels", transitTunnels);
+			SetMaxNumTransitTunnels (transitTunnels);
 
 			bool isFloodfill; i2p::config::GetOption("floodfill", isFloodfill);
 			if (isFloodfill) {
diff --git a/I2NPProtocol.cpp b/I2NPProtocol.cpp
index 7cebf96a..9674fdca 100644
--- a/I2NPProtocol.cpp
+++ b/I2NPProtocol.cpp
@@ -286,6 +286,16 @@ namespace i2p
 		return !msg->GetPayload ()[DATABASE_STORE_TYPE_OFFSET]; // 0- RouterInfo
 	}	
 	
+	static uint16_t g_MaxNumTransitTunnels = DEFAULT_MAX_NUM_TRANSIT_TUNNELS; // TODO:
+	void SetMaxNumTransitTunnels (uint16_t maxNumTransitTunnels)
+	{
+		if (maxNumTransitTunnels > 0 && maxNumTransitTunnels <= 10000 && g_MaxNumTransitTunnels != maxNumTransitTunnels)
+		{
+			LogPrint (eLogDebug, "I2NP: Max number of  transit tunnels set to ", maxNumTransitTunnels);
+			g_MaxNumTransitTunnels = maxNumTransitTunnels;
+		}
+	}
+
 	bool HandleBuildRequestRecords (int num, uint8_t * records, uint8_t * clearText)
 	{
 		for (int i = 0; i < num; i++)
@@ -298,7 +308,7 @@ namespace i2p
 				i2p::crypto::ElGamalDecrypt (i2p::context.GetEncryptionPrivateKey (), record + BUILD_REQUEST_RECORD_ENCRYPTED_OFFSET, clearText);
 				// replace record to reply			
 				if (i2p::context.AcceptsTunnels () && 
-					i2p::tunnel::tunnels.GetTransitTunnels ().size () <= MAX_NUM_TRANSIT_TUNNELS &&
+					i2p::tunnel::tunnels.GetTransitTunnels ().size () <= g_MaxNumTransitTunnels &&
 					!i2p::transport::transports.IsBandwidthExceeded ())
 				{	
 					auto transitTunnel = i2p::tunnel::CreateTransitTunnel (
diff --git a/I2NPProtocol.h b/I2NPProtocol.h
index 6450e958..cf8f4266 100644
--- a/I2NPProtocol.h
+++ b/I2NPProtocol.h
@@ -97,8 +97,6 @@ namespace i2p
 	const uint8_t DATABASE_LOOKUP_TYPE_ROUTERINFO_LOOKUP = 0x08; // 1000			
 	const uint8_t DATABASE_LOOKUP_TYPE_EXPLORATORY_LOOKUP = 0x0C; // 1100
 
-	const unsigned int MAX_NUM_TRANSIT_TUNNELS = 2500;
-
 namespace tunnel
 {		
 	class InboundTunnel;
@@ -259,6 +257,9 @@ namespace tunnel
 
 			std::vector<std::shared_ptr<I2NPMessage> > m_TunnelMsgs, m_TunnelGatewayMsgs;
 	};
+
+	const uint16_t DEFAULT_MAX_NUM_TRANSIT_TUNNELS = 2500;
+	void SetMaxNumTransitTunnels (uint16_t maxNumTransitTunnels);
 }	
 
 #endif