update SSU2 introducers if Firewalled

libi2pd/RouterInfo.cpp

@@ -1321,7 +1321,7 @@ namespace data
 				size_t len = address.IsSSU2 () ? 32 : 16;
 				WriteString (address.i.ToBase64 (len), properties); properties << ';';
 			}
-			if (address.transportStyle == eTransportSSU || (address.IsSSU2 () && isPublished))
+			if (address.transportStyle == eTransportSSU || address.IsSSU2 ())
 			{
 				// write introducers if any
 				if (address.ssu && !address.ssu->introducers.empty())

libi2pd/SSU2.cpp

@@ -21,7 +21,9 @@ namespace transport
 		RunnableServiceWithWork ("SSU2"), m_ReceiveService ("SSU2r"),
 		m_SocketV4 (m_ReceiveService.GetService ()), m_SocketV6 (m_ReceiveService.GetService ()),
 		m_AddressV4 (boost::asio::ip::address_v4()), m_AddressV6 (boost::asio::ip::address_v6()),
-		m_TerminationTimer (GetService ()), m_ResendTimer (GetService ())
+		m_TerminationTimer (GetService ()), m_ResendTimer (GetService ()), 
+		m_IntroducersUpdateTimer (GetService ()), m_IntroducersUpdateTimerV6 (GetService ()),
+		m_IsPublished (true)
 	{
 	}
 
@@ -30,6 +32,7 @@ namespace transport
 		if (!IsRunning ())
 		{
 			StartIOService ();
+			i2p::config::GetOption ("ssu2.published", m_IsPublished);
 			bool found = false;
 			auto& addresses = i2p::context.GetRouterInfo ().GetAddresses ();
 			for (const auto& address: addresses)
@@ -59,6 +62,7 @@ namespace transport
 								{
 									Receive (m_SocketV4);
 								});
+							ScheduleIntroducersUpdateTimer (); // wait for 30 seconds and decide if we need introducers
 						}
 						if (address->IsV6 ())
 						{
@@ -69,6 +73,7 @@ namespace transport
 								{
 									Receive (m_SocketV6);
 								});
+							ScheduleIntroducersUpdateTimerV6 (); // wait for 30 seconds and decide if we need introducers
 						}
 					}
 					else
@@ -828,5 +833,89 @@ namespace transport
 			}
 		}
 	}
+
+	void SSU2Server::ScheduleIntroducersUpdateTimer ()
+	{
+		if (m_IsPublished)
+		{	
+			m_IntroducersUpdateTimer.expires_from_now (boost::posix_time::seconds(SSU2_KEEP_ALIVE_INTERVAL));
+			m_IntroducersUpdateTimer.async_wait (std::bind (&SSU2Server::HandleIntroducersUpdateTimer,
+				this, std::placeholders::_1, true));
+		}	
+	}	
+
+	void SSU2Server::RescheduleIntroducersUpdateTimer ()
+	{
+		if (m_IsPublished)
+		{
+			m_IntroducersUpdateTimer.cancel ();
+			m_IntroducersUpdateTimer.expires_from_now (boost::posix_time::seconds(SSU2_KEEP_ALIVE_INTERVAL/2));
+			m_IntroducersUpdateTimer.async_wait (std::bind (&SSU2Server::HandleIntroducersUpdateTimer,
+				this, std::placeholders::_1, true));
+		}	
+	}
+
+	void SSU2Server::ScheduleIntroducersUpdateTimerV6 ()
+	{
+		if (m_IsPublished)
+		{	
+			m_IntroducersUpdateTimerV6.expires_from_now (boost::posix_time::seconds(SSU2_KEEP_ALIVE_INTERVAL));
+			m_IntroducersUpdateTimerV6.async_wait (std::bind (&SSU2Server::HandleIntroducersUpdateTimer,
+				this, std::placeholders::_1, false));
+		}	
+	}	
+
+	void SSU2Server::RescheduleIntroducersUpdateTimerV6 ()
+	{
+		if (m_IsPublished)
+		{
+			m_IntroducersUpdateTimerV6.cancel ();
+			m_IntroducersUpdateTimerV6.expires_from_now (boost::posix_time::seconds(SSU2_KEEP_ALIVE_INTERVAL/2));
+			m_IntroducersUpdateTimerV6.async_wait (std::bind (&SSU2Server::HandleIntroducersUpdateTimer,
+				this, std::placeholders::_1, false));
+		}	
+	}
+		
+	void SSU2Server::HandleIntroducersUpdateTimer (const boost::system::error_code& ecode, bool v4)
+	{
+		if (ecode != boost::asio::error::operation_aborted)
+		{
+			// timeout expired
+			if (v4)
+			{
+				if (i2p::context.GetStatus () == eRouterStatusTesting)
+				{
+					// we still don't know if we need introducers
+					ScheduleIntroducersUpdateTimer ();
+					return;
+				}
+				if (i2p::context.GetStatus () != eRouterStatusFirewalled)
+				{
+					// we don't need introducers
+					m_Introducers.clear ();
+					return;
+				}
+				UpdateIntroducers (true);
+				ScheduleIntroducersUpdateTimer ();
+			}
+			else
+			{
+				if (i2p::context.GetStatusV6 () == eRouterStatusTesting)
+				{
+					// we still don't know if we need introducers
+					ScheduleIntroducersUpdateTimerV6 ();
+					return;
+				}
+				if (i2p::context.GetStatusV6 () != eRouterStatusFirewalled)
+				{
+					// we don't need introducers
+					m_IntroducersV6.clear ();
+					return;
+				}
+				UpdateIntroducers (false);
+				ScheduleIntroducersUpdateTimerV6 ();
+			}	
+		}
+	}	
 }
 }

libi2pd/SSU2.h

@@ -23,6 +23,7 @@ namespace transport
 	const size_t SSU2_MAX_NUM_INTRODUCERS = 3;
 	const int SSU2_TO_INTRODUCER_SESSION_DURATION = 3600; // 1 hour
 	const int SSU2_TO_INTRODUCER_SESSION_EXPIRATION = 4800; // 80 minutes
+	const int SSU2_KEEP_ALIVE_INTERVAL = 30; // 30 seconds
 		
 	class SSU2Server: private i2p::util::RunnableServiceWithWork
 	{
@@ -82,6 +83,8 @@ namespace transport
 			uint64_t GetIncomingToken (const boost::asio::ip::udp::endpoint& ep);
 			std::pair<uint64_t, uint32_t> NewIncomingToken (const boost::asio::ip::udp::endpoint& ep);
 		
+			void RescheduleIntroducersUpdateTimer ();
+			void RescheduleIntroducersUpdateTimerV6 ();
 		
 		private:
 
@@ -103,6 +106,9 @@ namespace transport
 			std::list<std::shared_ptr<SSU2Session> > FindIntroducers (int maxNumIntroducers, 
 				bool v4, const std::set<i2p::data::IdentHash>& excluded) const;
 			void UpdateIntroducers (bool v4);
+			void ScheduleIntroducersUpdateTimer ();
+			void HandleIntroducersUpdateTimer (const boost::system::error_code& ecode, bool v4);
+			void ScheduleIntroducersUpdateTimerV6 ();
 					
 		private:
 
@@ -116,8 +122,10 @@ namespace transport
 			std::map<uint32_t, std::shared_ptr<SSU2Session> > m_Relays; // we are introducer, relay tag -> session
 			std::list<std::shared_ptr<SSU2Session> > m_Introducers, m_IntroducersV6; // introducers we are connected to
 			i2p::util::MemoryPoolMt<Packet> m_PacketsPool;
-			boost::asio::deadline_timer m_TerminationTimer, m_ResendTimer;
+			boost::asio::deadline_timer m_TerminationTimer, m_ResendTimer,
+				m_IntroducersUpdateTimer, m_IntroducersUpdateTimerV6;
 			std::shared_ptr<SSU2Session> m_LastSession;
+			bool m_IsPublished; // if we maintain introducers
 			
 		public:
 

libi2pd/SSU2Session.cpp

@@ -1831,7 +1831,13 @@ namespace transport
 									else
 									{
 										if (GetRouterStatus () == eRouterStatusTesting)
+										{	
 											SetRouterStatus (eRouterStatusFirewalled);
+											if (m_Address->IsV4 ())
+												m_Server.RescheduleIntroducersUpdateTimer ();
+											else
+												m_Server.RescheduleIntroducersUpdateTimerV6 ();
+										}	
 									}	
 								}
 								else