return relay tag for ipv6 introducer

libi2pd/NetDb.cpp

@@ -1172,7 +1172,7 @@ namespace data
 		return GetRandomRouter (
 			[](std::shared_ptr<const RouterInfo> router)->bool
 			{
-				return router->IsIntroducer () && !router->IsHidden () && !router->IsFloodfill (); // floodfills don't send relay tag
+				return router->IsIntroducer (true) && !router->IsHidden () && !router->IsFloodfill (); // floodfills don't send relay tag
 			});
 	}
 

libi2pd/RouterInfo.cpp

@@ -1105,8 +1105,7 @@ namespace data
 
 	bool RouterInfo::IsPeerTesting (bool v4) const
 	{
-		auto supportedTransports = m_SupportedTransports & (v4 ? eSSUV4 : eSSUV6);
+		if (!(m_SupportedTransports & (v4 ? eSSUV4 : eSSUV6))) return false; 
-		if (!supportedTransports) return false; 
 		return (bool)GetAddress (
 			[v4](std::shared_ptr<const RouterInfo::Address> address)->bool
 			{			
@@ -1115,14 +1114,14 @@ namespace data
 			});	
 	}
 
-	bool RouterInfo::IsIntroducer () const
+	bool RouterInfo::IsIntroducer (bool v4) const
 	{
-		// TODO: support ipv6
+		if (!(m_SupportedTransports & (v4 ? eSSUV4 : eSSUV6))) return false; 
-		if (!(m_SupportedTransports & eSSUV4)) return false;
 		return (bool)GetAddress (
-			[](std::shared_ptr<const RouterInfo::Address> address)->bool
+			[v4](std::shared_ptr<const RouterInfo::Address> address)->bool
 			{			
-				return (address->transportStyle == eTransportSSU) && address->IsIntroducer ();
+				return (address->transportStyle == eTransportSSU) && address->IsIntroducer () &&
+					((v4 && address->IsV4 ()) || (!v4 && address->IsV6 ()));
 			});
 	}	
 

libi2pd/RouterInfo.h

@@ -210,7 +210,7 @@ namespace data
 			bool IsExtraBandwidth () const { return m_Caps & RouterInfo::eExtraBandwidth; };
 			bool IsEligibleFloodfill () const;
 			bool IsPeerTesting (bool v4) const;	
-			bool IsIntroducer () const;	
+			bool IsIntroducer (bool v4) const;	
 		
 			uint8_t GetCaps () const { return m_Caps; };
 			void SetCaps (uint8_t caps);

libi2pd/SSUSession.cpp

@@ -212,7 +212,7 @@ namespace transport
 		{
 			uint8_t extendedOptionsLen = buf[headerSize];
 			headerSize++;
-			if (extendedOptionsLen >= 3) // options are presented
+			if (extendedOptionsLen >= 2) // options are presented
 			{
 				uint16_t flags = bufbe16toh (buf + headerSize);
 				sendRelayTag = flags & EXTENDED_OPTIONS_FLAG_REQUEST_RELAY_TAG;
@@ -464,7 +464,7 @@ namespace transport
 		else
 			s.Insert (address->host.to_v6 ().to_bytes ().data (), 16); // our IP V6
 		s.Insert<uint16_t> (htobe16 (address->port)); // our port
-		if (sendRelayTag && i2p::context.GetRouterInfo ().IsIntroducer () && !IsV6 ())
+		if (sendRelayTag && i2p::context.GetRouterInfo ().IsIntroducer (!IsV6 ()))
 		{
 			RAND_bytes((uint8_t *)&m_SentRelayTag, 4);
 			if (!m_SentRelayTag) m_SentRelayTag = 1;