ri, transports, binding, reserved ip ranges

libi2pd/NTCPSession.cpp

@@ -14,6 +14,7 @@
 #include "NTCPSession.h"
 #include "HTTP.h"
 #include "util.h"
+#include "Config.h"
 #ifdef WITH_EVENTS
 #include "Event.h"
 #endif
@@ -815,43 +816,52 @@ namespace transport
 			else
 			{
 				// create acceptors
+				bool ipv4; i2p::config::GetOption("ipv4", ipv4);
+				bool ipv6; i2p::config::GetOption("ipv6", ipv6);
+
 				auto& addresses = context.GetRouterInfo ().GetAddresses ();
 				for (const auto& address: addresses)
 				{
 					if (!address) continue;
 					if (address->transportStyle == i2p::data::RouterInfo::eTransportNTCP && !address->IsNTCP2 ())
 					{
-						if (address->host.is_v4())
+						if (address->host.is_v4() && context.SupportsV4 () && ipv4)
 						{
 							try
 							{
-								m_NTCPAcceptor = new boost::asio::ip::tcp::acceptor (m_Service, boost::asio::ip::tcp::endpoint(boost::asio::ip::tcp::v4(), address->port));
+								m_NTCPAcceptor = new boost::asio::ip::tcp::acceptor (m_Service);
+								m_NTCPAcceptor->open (boost::asio::ip::tcp::v4());
+								m_NTCPAcceptor->set_option (boost::asio::socket_base::reuse_address (true));
+								m_NTCPAcceptor->bind (boost::asio::ip::tcp::endpoint(boost::asio::ip::tcp::v4(), address->port));
+								m_NTCPAcceptor->listen ();
+
+								LogPrint (eLogInfo, "NTCP: Start listening IPv4 TCP port ", address->port);
+								auto conn = std::make_shared<NTCPSession>(*this);
+								m_NTCPAcceptor->async_accept(conn->GetSocket (), std::bind (&NTCPServer::HandleAccept, this, conn, std::placeholders::_1));
 							} catch ( std::exception & ex ) {
-								/** fail to bind ip4 */
+								/** fail to bind IPv4 */
-								LogPrint(eLogError, "NTCP: Failed to bind to ip4 port ",address->port, ex.what());
+								LogPrint(eLogError, "NTCP: Failed to bind to IPv4 port ",address->port, ex.what());
 								continue;
 							}
 
-							LogPrint (eLogInfo, "NTCP: Start listening TCP port ", address->port);
-							auto conn = std::make_shared<NTCPSession>(*this);
-							m_NTCPAcceptor->async_accept(conn->GetSocket (), std::bind (&NTCPServer::HandleAccept, this, conn, std::placeholders::_1));
 						}
-						else if (address->host.is_v6() && context.SupportsV6 ())
+						else if (address->host.is_v6() && context.SupportsV6 () && ipv6)
 						{
-							m_NTCPV6Acceptor = new boost::asio::ip::tcp::acceptor (m_Service);
 							try
 							{
+								m_NTCPV6Acceptor = new boost::asio::ip::tcp::acceptor (m_Service);
 								m_NTCPV6Acceptor->open (boost::asio::ip::tcp::v6());
 								m_NTCPV6Acceptor->set_option (boost::asio::ip::v6_only (true));
 								m_NTCPV6Acceptor->set_option (boost::asio::socket_base::reuse_address (true));
 								m_NTCPV6Acceptor->bind (boost::asio::ip::tcp::endpoint(boost::asio::ip::tcp::v6(), address->port));
 								m_NTCPV6Acceptor->listen ();
 
-								LogPrint (eLogInfo, "NTCP: Start listening V6 TCP port ", address->port);
+								LogPrint (eLogInfo, "NTCP: Start listening IPv6 TCP port ", address->port);
 								auto conn = std::make_shared<NTCPSession> (*this);
 								m_NTCPV6Acceptor->async_accept(conn->GetSocket (), std::bind (&NTCPServer::HandleAcceptV6, this, conn, std::placeholders::_1));
 							} catch ( std::exception & ex ) {
-								LogPrint(eLogError, "NTCP: failed to bind to ip6 port ", address->port);
+								/** fail to bind IPv6 */
+								LogPrint(eLogError, "NTCP: failed to bind to IPv6 port ", address->port);
 								continue;
 							}
 						}

libi2pd/RouterContext.cpp

@@ -570,8 +570,10 @@ namespace i2p
 
 	bool RouterContext::Load ()
 	{
+		// read router keys
 		std::ifstream fk (i2p::fs::DataDirPath (ROUTER_KEYS), std::ifstream::in | std::ifstream::binary);
-		if (!fk.is_open ())	return false;
+		if (!fk.is_open ())
+			return false;
 		fk.seekg (0, std::ios::end);
 		size_t len = fk.tellg();
 		fk.seekg (0, std::ios::beg);
@@ -589,6 +591,8 @@ namespace i2p
 			m_Keys.FromBuffer (buf, len);
 			delete[] buf;
 		}
+		fk.close();
+
 		// read NTCP2 keys if available
 		std::ifstream n2k (i2p::fs::DataDirPath (NTCP2_KEYS), std::ifstream::in | std::ifstream::binary);
 		if (n2k)
@@ -603,6 +607,7 @@ namespace i2p
 			}
 			n2k.close ();
 		}
+
 		// read RouterInfo
 		m_RouterInfo.SetRouterIdentity (GetIdentity ());
 		i2p::data::RouterInfo routerInfo(i2p::fs::DataDirPath (ROUTER_INFO));
@@ -615,6 +620,11 @@ namespace i2p
 			// Migration to 0.9.24. TODO: remove later
 			m_RouterInfo.DeleteProperty ("coreVersion");
 			m_RouterInfo.DeleteProperty ("stat_uptime");
+
+			bool ipv4; i2p::config::GetOption("ipv4", ipv4);
+			bool ipv6; i2p::config::GetOption("ipv6", ipv6);
+			SetSupportsV4(ipv4);
+			SetSupportsV6(ipv6);
 		}
 		else
 		{

libi2pd/RouterInfo.cpp

@@ -245,13 +245,15 @@ namespace data
 					ExtractCaps (value);
 				else if (!strcmp (key, "s")) // ntcp2 static key
 				{
-					if (!address->ntcp2) address->ntcp2.reset (new NTCP2Ext ());
+					if (!address->ntcp2)
+						address->ntcp2.reset (new NTCP2Ext ());
 					supportedTransports |= (address->host.is_v4 ()) ? eNTCP2V4 : eNTCP2V6;
 					Base64ToByteStream (value, strlen (value), address->ntcp2->staticKey, 32);
 				}
 				else if (!strcmp (key, "i")) // ntcp2 iv
 				{
-					if (!address->ntcp2) address->ntcp2.reset (new NTCP2Ext ());
+					if (!address->ntcp2)
+						address->ntcp2.reset (new NTCP2Ext ());
 					supportedTransports |= (address->host.is_v4 ()) ? eNTCP2V4 : eNTCP2V6;
 					Base64ToByteStream (value, strlen (value), address->ntcp2->iv, 16);
 					address->ntcp2->isPublished = true; // presence if "i" means "published"
@@ -292,8 +294,10 @@ namespace data
 				}
 				if (!s) return;
 			}
-			if (introducers) supportedTransports |= eSSUV4; // in case if host is not presented
+			if (introducers)
-			if (isNTCP2Only && address->ntcp2) address->ntcp2->isNTCP2Only = true;
+				supportedTransports |= eSSUV4; // in case if host is not presented
+			if (isNTCP2Only && address->ntcp2)
+				address->ntcp2->isNTCP2Only = true;
 			if (supportedTransports)
 			{
 				addresses->push_back(address);
@@ -799,7 +803,7 @@ namespace data
 
 	bool RouterInfo::IsV6 () const
 	{
-		return m_SupportedTransports & (eNTCPV6 | eSSUV6);
+		return m_SupportedTransports & (eNTCPV6 | eSSUV6 | eNTCP2V6);
 	}
 
 	bool RouterInfo::IsV4 () const
@@ -819,7 +823,6 @@ namespace data
 			m_SupportedTransports |= eNTCPV4 | eSSUV4 | eNTCP2V4;
 	}
 
-
 	void RouterInfo::DisableV6 ()
 	{
 		if (IsV6 ())
@@ -852,7 +855,6 @@ namespace data
 		}
 	}
 
-
 	bool RouterInfo::UsesIntroducer () const
 	{
 		return m_Caps & Caps::eUnreachable; // non-reachable

libi2pd/SSU.cpp

@@ -10,30 +10,17 @@ namespace i2p
 {
 namespace transport
 {
-
-	SSUServer::SSUServer (const boost::asio::ip::address & addr, int port):
-		m_OnlyV6(true), m_IsRunning(false),
-		m_Thread (nullptr), m_ThreadV6 (nullptr), m_ReceiversThread (nullptr),
-		m_ReceiversThreadV6 (nullptr), m_Work (m_Service), m_WorkV6 (m_ServiceV6),
-		m_ReceiversWork (m_ReceiversService), m_ReceiversWorkV6 (m_ReceiversServiceV6),
-		m_EndpointV6 (addr, port), m_Socket (m_ReceiversService, m_Endpoint),
-		m_SocketV6 (m_ReceiversServiceV6), m_IntroducersUpdateTimer (m_Service),
-		m_PeerTestsCleanupTimer (m_Service), m_TerminationTimer (m_Service),
-		m_TerminationTimerV6 (m_ServiceV6)
-	{
-		OpenSocketV6 ();
-	}
-
 	SSUServer::SSUServer (int port):
-		m_OnlyV6(false), m_IsRunning(false),
+		m_IsRunning(false), m_Thread (nullptr), m_ThreadV6 (nullptr),
-		m_Thread (nullptr), m_ThreadV6 (nullptr), m_ReceiversThread (nullptr),
+		m_ReceiversThread (nullptr), m_ReceiversThreadV6 (nullptr),
-		m_ReceiversThreadV6 (nullptr), 	m_Work (m_Service), m_WorkV6 (m_ServiceV6),
+		m_Work (m_Service), m_WorkV6 (m_ServiceV6),
 		m_ReceiversWork (m_ReceiversService), m_ReceiversWorkV6 (m_ReceiversServiceV6),
 		m_Endpoint (boost::asio::ip::udp::v4 (), port), m_EndpointV6 (boost::asio::ip::udp::v6 (), port),
 		m_Socket (m_ReceiversService), m_SocketV6 (m_ReceiversServiceV6),
 		m_IntroducersUpdateTimer (m_Service), m_PeerTestsCleanupTimer (m_Service),
 		m_TerminationTimer (m_Service), m_TerminationTimerV6 (m_ServiceV6)
 	{
+		if (context.SupportsV4 ())
 			OpenSocket ();
 		if (context.SupportsV6 ())
 			OpenSocketV6 ();
@@ -63,7 +50,7 @@ namespace transport
 	void SSUServer::Start ()
 	{
 		m_IsRunning = true;
-		if (!m_OnlyV6)
+		if (context.SupportsV4 ())
 		{
 			m_ReceiversThread = new std::thread (std::bind (&SSUServer::RunReceivers, this));
 			m_Thread = new std::thread (std::bind (&SSUServer::Run, this));
@@ -795,4 +782,3 @@ namespace transport
 	}
 }
 }
-

libi2pd/Transports.cpp

@@ -227,10 +227,7 @@ namespace transport
 			{
 				if (m_SSUServer == nullptr && enableSSU)
 				{
-					if (address->host.is_v4())
 					m_SSUServer = new SSUServer (address->port);
-					else
-						m_SSUServer = new SSUServer (address->host, address->port);
 					LogPrint (eLogInfo, "Transports: Start listening UDP port ", address->port);
 					try {
 						m_SSUServer->Start ();
@@ -408,23 +405,19 @@ namespace transport
 			if (!peer.numAttempts) // NTCP2
 			{
 				peer.numAttempts++;
-				if (m_NTCP2Server) // we support NTCP2
-				{
-					// NTCP2 have priority over NTCP
 				auto address = peer.router->GetNTCP2Address (true, !context.SupportsV6 ()); // published only
-					if (address)
+				if (address && m_NTCP2Server && !i2p::util::net::IsInReservedRange(address->host)) 
-					{
+				{ // we support NTCP2, it has priority over NTCP and remote address is not in reserved range
 					auto s = std::make_shared<NTCP2Session> (*m_NTCP2Server, peer.router);
 					m_NTCP2Server->Connect (address->host, address->port, s);
 					return true;
 				}
 			}
-			}
 			if (peer.numAttempts == 1) // NTCP1
 			{
 				peer.numAttempts++;
 				auto address = peer.router->GetNTCPAddress (!context.SupportsV6 ());
-				if (address && m_NTCPServer)
+				if (address && m_NTCPServer && !i2p::util::net::IsInReservedRange(address->host))
 				{
 					if (!peer.router->UsesIntroducer () && !peer.router->IsUnreachable ())
 					{
@@ -457,14 +450,14 @@ namespace transport
 			if (peer.numAttempts == 2)// SSU
 			{
 				peer.numAttempts++;
-				if (m_SSUServer && peer.router->IsSSU (!context.SupportsV6 ()))
-				{
 				auto address = peer.router->GetSSUAddress (!context.SupportsV6 ());
+				if (address && m_SSUServer && !i2p::util::net::IsInReservedRange(address->host))
+				{
 					m_SSUServer->CreateSession (peer.router, address->host, address->port);
 					return true;
 				}
 			}
-			LogPrint (eLogInfo, "Transports: No NTCP or SSU addresses available");
+			LogPrint (eLogInfo, "Transports: No valid NTCP2, NTCP or SSU remote addresses available");
 			peer.Done ();
 			std::unique_lock<std::mutex> l(m_PeersMutex);
 			m_Peers.erase (ident);

libi2pd/util.cpp

@@ -337,9 +337,41 @@ namespace net
 			LogPrint(eLogWarning, "NetIface: cannot find ipv4 address for interface ", ifname);
 		}
 		return boost::asio::ip::address::from_string(fallback);
-
 #endif
 	}
+
+	bool IsInReservedRange(const boost::asio::ip::address& host) {
+		if(host.is_v6())
+			return false; // for now checking only v4
+		
+		// https://en.wikipedia.org/wiki/Reserved_IP_addresses
+		std::string reservedIPv4Ranges[][2] = {
+			{"0.0.0.0",      "0.255.255.255"},
+			{"10.0.0.0",     "10.255.255.255"},
+			{"100.64.0.0",   "100.127.255.255"},
+			{"127.0.0.0",    "127.255.255.255"},
+			{"169.254.0.0",  "169.254.255.255"},
+			{"172.16.0.0",   "172.31.255.255"},
+			{"192.0.0.0",    "192.0.0.255"},
+			{"192.0.2.0",    "192.0.2.255"},
+			{"192.88.99.0",  "192.88.99.255"},
+			{"192.168.0.0",  "192.168.255.255"},
+			{"198.18.0.0",   "192.19.255.255"},
+			{"198.51.100.0", "198.51.100.255"},
+			{"203.0.113.0",  "203.0.113.255"},
+			{"224.0.0.0",    "255.255.255.255"}
+		};
+
+		for(int i = 0; i < sizeof(reservedIPv4Ranges); i++) {
+			uint32_t rangeStart = boost::asio::ip::address_v4::from_string(reservedIPv4Ranges[i][0]).to_ulong();
+			uint32_t rangeEnd   = boost::asio::ip::address_v4::from_string(reservedIPv4Ranges[i][1]).to_ulong();
+			uint32_t ip_address = host.to_v4().to_ulong();
+
+			if (ip_address >= rangeStart &&	ip_address <= rangeEnd)
+				return true;
 		}
+		return false;
+	}
+} // net
 } // util
 } // i2p

libi2pd/util.h

@@ -126,6 +126,7 @@ namespace util
 	{
 		int GetMTU (const boost::asio::ip::address& localAddress);
 		const boost::asio::ip::address GetInterfaceAddress(const std::string & ifname, bool ipv6=false);
+		bool IsInReservedRange(const boost::asio::ip::address& host);
 	}
 }
 }