Exploratory

I2NPProtocol.cpp

@@ -81,25 +81,44 @@ namespace i2p
 		return CreateI2NPMessage (eI2NPDeliveryStatus, (uint8_t *)&msg, sizeof (msg));
 	}
 
-	I2NPMessage * CreateDatabaseLookupMsg (const uint8_t * key, const uint8_t * from, uint32_t replyTunnelID)
+	I2NPMessage * CreateDatabaseLookupMsg (const uint8_t * key, const uint8_t * from, 
+		uint32_t replyTunnelID, bool exploratory)
 	{
-#pragma pack(1)
-		struct
+		I2NPMessage * m = NewI2NPMessage ();
+		uint8_t * buf = m->GetPayload ();
+		memcpy (buf, key, 32); // key
+		buf += 32;
+		memcpy (buf, from, 32); // from
+		buf += 32;
+		if (replyTunnelID)
 		{
-			uint8_t key[32];
-			uint8_t from[32];
-			uint8_t flags;
-			uint32_t replyTunnelID;
-			uint16_t size;		
-		} msg;		
-#pragma pack ()	
+			*buf = 0x01; // set delivery flag
+			*(uint32_t *)(buf+1) = htobe32 (replyTunnelID);
+			buf += 5;
+		}
+		else
+		{	
+			*buf = 0; // flag
+			buf++;
+		}	
 		
-		memcpy (msg.key, key, 32);
-		memcpy (msg.from, from, 32);
-		msg.flags = replyTunnelID ? 0x01 : 0;
-		msg.replyTunnelID = htobe32 (replyTunnelID);
-		msg.size = 0;
-		return CreateI2NPMessage (eI2NPDatabaseLookup, (uint8_t *)&msg, sizeof (msg));
+		if (exploratory)
+		{
+			*(uint16_t *)buf = htobe16 (1); // one exlude record
+			buf += 2;
+			// reply with non-floodfill routers only
+			memset (buf, 0, 32);
+			buf += 32;
+		}
+		else
+		{
+			// nothing to exclude
+			*(uint16_t *)buf = htobe16 (0);
+			buf += 2;
+		}	
+		m->len += (buf - m->GetPayload ()); 
+		FillI2NPMessageHeader (m, eI2NPDatabaseLookup);
+		return m; 
 	}	
 
 	I2NPMessage * CreateDatabaseStoreMsg ()
@@ -167,7 +186,7 @@ namespace i2p
 			peerHash[l1] = 0;
 			LogPrint (i,": ", peerHash);	
 
-			i2p::data::netdb.RequestDestination (msg->key, buf + sizeof (*msg) +i*32);
+			i2p::data::netdb.HandleDatabaseSearchReply (msg->key, buf + sizeof (*msg) +i*32);
 		}	
 	}	
 
@@ -211,8 +230,18 @@ namespace i2p
 		i2p::tunnel::Tunnel * tunnel =  i2p::tunnel::tunnels.GetPendingTunnel (replyMsgID);
 		if (tunnel)
 		{
+			// endpoint of inbound tunnel
 			LogPrint ("VariableTunnelBuild reply for tunnel ", tunnel->GetTunnelID ());
-			tunnel->HandleVariableTunnelBuildReplyMsg (buf, len);
+			if (tunnel->HandleTunnelBuildResponse (buf, len))
+			{
+				LogPrint ("Inbound tunnel ", tunnel->GetTunnelID (), " has been created");
+				i2p::tunnel::tunnels.AddInboundTunnel (static_cast<i2p::tunnel::InboundTunnel *>(tunnel));
+			}
+			else
+			{
+				LogPrint ("Inbound tunnel ", tunnel->GetTunnelID (), " has been declined");
+				delete tunnel;
+			}	
 		}
 		else
 		{
@@ -269,8 +298,17 @@ namespace i2p
 		i2p::tunnel::Tunnel * tunnel = i2p::tunnel::tunnels.GetPendingTunnel (replyMsgID);
 		if (tunnel)
 		{	
-			tunnel->HandleVariableTunnelBuildReplyMsg (buf, len);
-			LogPrint ("Tunnel ", tunnel->GetTunnelID (), " has been created");
+			// reply for outbound tunnel
+			if (tunnel->HandleTunnelBuildResponse (buf, len))
+			{	
+				LogPrint ("Outbound tunnel ", tunnel->GetTunnelID (), " has been created");
+				i2p::tunnel::tunnels.AddOutboundTunnel (static_cast<i2p::tunnel::OutboundTunnel *>(tunnel));
+			}	
+			else
+			{	
+				LogPrint ("Outbound tunnel ", tunnel->GetTunnelID (), " has been declined");
+				delete tunnel;
+			}	
 		}	
 		else
 			LogPrint ("Pending tunnel for message ", replyMsgID, " not found");

I2NPProtocol.h

@@ -27,6 +27,7 @@ namespace i2p
 		uint16_t size;		
 	};
 
+	
 	struct I2NPBuildRequestRecordClearText
 	{
 		uint32_t receiveTunnel;
@@ -104,7 +105,8 @@ namespace i2p
 	I2NPMessage * CreateI2NPMessage (const uint8_t * buf, int len);
 	
 	I2NPMessage * CreateDeliveryStatusMsg ();
-	I2NPMessage * CreateDatabaseLookupMsg (const uint8_t * key, const uint8_t * from, uint32_t replyTunnelID);
+	I2NPMessage * CreateDatabaseLookupMsg (const uint8_t * key, const uint8_t * from, 
+		uint32_t replyTunnelID, bool exploratory = false);
 	I2NPMessage * CreateDatabaseStoreMsg ();
 	
 	void HandleDatabaseStoreMsg (uint8_t * buf, size_t len);

NetDb.cpp

@@ -2,6 +2,7 @@
 #include "Log.h"
 #include "I2NPProtocol.h"
 #include "Tunnel.h"
+#include "RouterContext.h"
 #include "NetDb.h"
 
 namespace i2p
@@ -11,19 +12,46 @@ namespace data
 	
 	NetDb netdb;
 
-	NetDb::NetDb ()
+	NetDb::NetDb (): m_IsRunning (false), m_Thread (0)
 	{
 		Load ("netDb");
 	}
 	
 	NetDb::~NetDb ()
 	{
+		Stop ();
 		for (auto l:m_LeaseSets)
 			delete l.second;
 		for (auto r:m_RouterInfos)
 			delete r.second;
 	}	
 
+	void NetDb::Start ()
+	{
+		m_Thread = new std::thread (std::bind (&NetDb::Run, this));
+	}
+	
+	void NetDb::Stop ()
+	{
+		if (m_Thread)
+		{	
+			m_IsRunning = false;
+			m_Thread->join (); 
+			delete m_Thread;
+			m_Thread = 0;
+		}	
+	}	
+	
+	void NetDb::Run ()
+	{
+		m_IsRunning = true;
+		while (m_IsRunning)
+		{	
+			sleep (10);
+			Explore ();
+		}	
+	}	
+	
 	void NetDb::AddRouterInfo (uint8_t * buf, int len)
 	{
 		RouterInfo * r = new RouterInfo (buf, len);
@@ -78,10 +106,9 @@ namespace data
 			i2p::tunnel::InboundTunnel * inbound = i2p::tunnel::tunnels.GetNextInboundTunnel ();
 			if (inbound)
 			{
-				I2NPMessage * msg = i2p::CreateDatabaseLookupMsg (destination, inbound->GetGatewayIdentHash (), 
-					inbound->GetGetwayTunnelID ());
+				I2NPMessage * msg = i2p::CreateDatabaseLookupMsg (destination, inbound->GetNextIdentHash (), 
+					inbound->GetNextTunnelID ());
 				outbound->SendTunnelDataMsg (router, 0, msg);
-				i2p::DeleteI2NPMessage (msg);
 			}	
 			else
 				LogPrint ("No inbound tunnels found");	
@@ -90,12 +117,63 @@ namespace data
 			LogPrint ("No outbound tunnels found");
 	}	
 
-	const RouterInfo * NetDb::GetNextFloodfill () const
+	void NetDb::HandleDatabaseSearchReply (const uint8_t * key, const uint8_t * router)	
+	{
+		if (!memcmp (m_Exploratory, key, 32))
+		{
+			if (m_RouterInfos.find (std::string ((const char *)router, 32)) == m_RouterInfos.end ())
+				LogPrint ("Found new router");
+			else
+				LogPrint ("Bayan");
+		}
+		else
+			RequestDestination (key, router);
+	}	
+
+	void NetDb::Explore ()
+	{
+		i2p::tunnel::OutboundTunnel * outbound = i2p::tunnel::tunnels.GetNextOutboundTunnel ();
+		i2p::tunnel::InboundTunnel * inbound = i2p::tunnel::tunnels.GetNextInboundTunnel ();
+		if (outbound && inbound)
+		{
+			const RouterInfo * floodFill = GetRandomNTCPRouter (true);
+			if (floodFill)
+			{
+				LogPrint ("Exploring new routers ...");
+				CryptoPP::RandomNumberGenerator& rnd = i2p::context.GetRandomNumberGenerator ();
+				rnd.GenerateBlock (m_Exploratory, 32);
+				I2NPMessage * msg = i2p::CreateDatabaseLookupMsg (m_Exploratory, inbound->GetNextIdentHash (), 
+					inbound->GetNextTunnelID (), true);
+				outbound->SendTunnelDataMsg (floodFill->GetIdentHash (), 0, msg);
+			}	
+		}
+	}	
+
+	const RouterInfo * NetDb::GetRandomNTCPRouter (bool floodfillOnly) const
 	{
+		CryptoPP::RandomNumberGenerator& rnd = i2p::context.GetRandomNumberGenerator ();
+		uint32_t ind = rnd.GenerateWord32 (0, m_RouterInfos.size () - 1), i = 0;
+		RouterInfo * last = nullptr;
 		for (auto it: m_RouterInfos)
-			if (it.second->IsFloodfill () && it.second->IsNTCP ())
-				return it.second;
-		return 0;
+		{	
+			if (it.second->IsNTCP () && (!floodfillOnly || it.second->IsFloodfill ()))
+				last = it.second;
+			if (i >= ind) break;
+			else i++;
+		}	
+		return last;
+	}	
+
+	const RouterInfo * NetDb::GetRandomRouter () const
+	{
+		CryptoPP::RandomNumberGenerator& rnd = i2p::context.GetRandomNumberGenerator ();
+		uint32_t ind = rnd.GenerateWord32 (0, m_RouterInfos.size () - 1), i = 0;
+		for (auto it: m_RouterInfos)
+		{	
+			if (i >= ind) return it.second;
+			else i++;
+		}	
+		return nullptr;
 	}	
 }
 }

NetDb.h

@@ -4,6 +4,7 @@
 #include <inttypes.h>
 #include <map>
 #include <string>
+#include <thread>
 #include "RouterInfo.h"
 #include "LeaseSet.h"
 
@@ -18,22 +19,33 @@ namespace data
 			NetDb ();
 			~NetDb ();
 
+			void Start ();
+			void Stop ();
+			
 			void AddRouterInfo (uint8_t * buf, int len);
 			void AddLeaseSet (uint8_t * buf, int len);
 			RouterInfo * FindRouter (const uint8_t * ident);
 			
 			void RequestDestination (const uint8_t * destination, const uint8_t * router);
+			void HandleDatabaseSearchReply (const uint8_t * key, const uint8_t * router);
 			
-			const RouterInfo * GetNextFloodfill () const;
+			const RouterInfo * GetRandomNTCPRouter (bool floodfillOnly = false) const;
+			const RouterInfo * GetRandomRouter () const;
 			
 		private:
 
 			void Load (const char * directory);
+			void Run (); // exploratory thread
+			void Explore ();
 			
 		private:
 
 			std::map<std::string, LeaseSet *> m_LeaseSets;
 			std::map<std::string, RouterInfo *> m_RouterInfos;
+
+			bool m_IsRunning;
+			std::thread * m_Thread;	
+			uint8_t m_Exploratory[32];
 	};
 
 	extern NetDb netdb;