bind NTCP2 connections to specified address

libi2pd/Config.cpp

@@ -50,7 +50,9 @@ namespace config {
 			("nat", bool_switch()->default_value(true),                       "Should we assume we are behind NAT? (default: enabled)")
 			("port", value<uint16_t>()->default_value(0),                     "Port to listen for incoming connections (default: auto)")
 			("ipv4", bool_switch()->default_value(true),                      "Enable communication through ipv4 (default: enabled)")
+			("address4", value<std::string>()->default_value(""),             "Local address to bind ipv4 transport sockets to")
 			("ipv6", bool_switch()->default_value(false),                     "Enable communication through ipv6 (default: disabled)")
+			("address6", value<std::string>()->default_value(""),             "Local address to bind ipv6 transport sockets to")
 			("reservedrange", bool_switch()->default_value(true),             "Check remote RI for being in blacklist of reserved IP ranges (default: enabled)")
 			("netid", value<int>()->default_value(I2PD_NET_ID),               "Specify NetID. Main I2P is 2")
 			("daemon", bool_switch()->default_value(false),                   "Router will go to background after start (default: disabled)")
@@ -247,7 +249,7 @@ namespace config {
 			("ntcp2.enabled", value<bool>()->default_value(true),          "Enable NTCP2 (default: enabled)")
 			("ntcp2.published", value<bool>()->default_value(true),        "Publish NTCP2 (default: enabled)")
 			("ntcp2.port", value<uint16_t>()->default_value(0),            "Port to listen for incoming NTCP2 connections (default: auto)")
-			("ntcp2.addressv6", value<std::string>()->default_value("::"), "Address to bind NTCP2 on")
+			("ntcp2.addressv6", value<std::string>()->default_value("::"), "Address to publish NTCP2 with")
 			("ntcp2.proxy", value<std::string>()->default_value(""),       "Proxy URL for NTCP2 transport")
 		;
 

libi2pd/NTCP2.cpp

@@ -1291,6 +1291,24 @@ namespace transport
 							conn->Terminate ();
 						}
 					});
+					// bind to local address
+					std::shared_ptr<boost::asio::ip::tcp::endpoint> localAddress;
+					if (conn->GetRemoteEndpoint ().address ().is_v6 ())
+					{	
+						if (i2p::util::net::IsYggdrasilAddress (conn->GetRemoteEndpoint ().address ()))
+							localAddress = m_YggdrasilAddress;
+						else 
+							localAddress = m_Address6;
+					}	
+					else
+						localAddress = m_Address4;
+					if (localAddress)
+					{
+						boost::system::error_code ec;
+						conn->GetSocket ().bind (*localAddress, ec);
+						if (ec)
+							LogPrint (eLogError, "NTCP2: can't bind to ", localAddress->address ().to_string (), ": ", ec.message ());	
+					}	
 					conn->GetSocket ().async_connect (conn->GetRemoteEndpoint (), std::bind (&NTCP2Server::HandleConnect, this, std::placeholders::_1, conn, timer));
 				}
 				else
@@ -1631,5 +1649,19 @@ namespace transport
 				conn->Terminate();
 			});
 	}
+
+	void NTCP2Server::SetLocalAddress (const boost::asio::ip::address& localAddress)
+	{	
+		auto addr = std::make_shared<boost::asio::ip::tcp::endpoint>(boost::asio::ip::tcp::endpoint(localAddress, 0));
+		if (localAddress.is_v6 ())
+		{	
+			if (i2p::util::net::IsYggdrasilAddress (localAddress))
+				m_YggdrasilAddress = addr;
+			else 
+				m_Address6 = addr;
+		}	
+		else
+			m_Address4 = addr;
+	}	
 }
 }

libi2pd/NTCP2.h

@@ -248,6 +248,8 @@ namespace transport
 			bool UsingProxy() const { return m_ProxyType != eNoProxy; };
 			void UseProxy(ProxyType proxy, const std::string & address, uint16_t port);
 
+			void SetLocalAddress (const boost::asio::ip::address& localAddress);
+			
 		private:
 
 			void HandleAccept (std::shared_ptr<NTCP2Session> conn, const boost::system::error_code& error);
@@ -273,6 +275,7 @@ namespace transport
 			uint16_t m_ProxyPort;
 			boost::asio::ip::tcp::resolver m_Resolver;
 			std::unique_ptr<boost::asio::ip::tcp::endpoint> m_ProxyEndpoint;
+			std::shared_ptr<boost::asio::ip::tcp::endpoint> m_Address4, m_Address6, m_YggdrasilAddress;
 			
 		public:
 

libi2pd/Transports.cpp

@@ -205,6 +205,46 @@ namespace transport
 			}
 		}
 
+		// bind to interfaces
+		bool ipv4; i2p::config::GetOption("ipv4", ipv4);
+		if (ipv4)
+		{
+			std::string address; i2p::config::GetOption("address4", address);
+			if (!address.empty ())
+			{	
+				boost::system::error_code ec;
+				auto addr = boost::asio::ip::address::from_string (address, ec);
+				if (!ec && m_NTCP2Server)
+					m_NTCP2Server->SetLocalAddress (addr);
+			}	
+		}	
+
+		bool ipv6; i2p::config::GetOption("ipv6", ipv6);
+		if (ipv6)
+		{
+			std::string address; i2p::config::GetOption("address6", address);
+			if (!address.empty ())
+			{	
+				boost::system::error_code ec;
+				auto addr = boost::asio::ip::address::from_string (address, ec);
+				if (!ec && m_NTCP2Server)
+					m_NTCP2Server->SetLocalAddress (addr);
+			}	
+		}
+
+		bool ygg; i2p::config::GetOption("meshnets.yggdrasil", ygg);
+		if (ygg)
+		{
+			std::string address; i2p::config::GetOption("meshnets.yggdrasil", address);
+			if (!address.empty ())
+			{	
+				boost::system::error_code ec;
+				auto addr = boost::asio::ip::address::from_string (address, ec);
+				if (!ec && m_NTCP2Server && i2p::util::net::IsYggdrasilAddress (addr))
+					m_NTCP2Server->SetLocalAddress (addr);
+			}	
+		}
+		
 		// create acceptors
 		auto& addresses = context.GetRouterInfo ().GetAddresses ();
 		for (const auto& address : addresses)