more fixes of misalignment

Destination.cpp

@@ -190,18 +190,17 @@ namespace client
 
 	void ClientDestination::HandleI2NPMessage (const uint8_t * buf, size_t len, i2p::tunnel::InboundTunnel * from)
 	{
-		//TODO: since we are accessing a uint8_t this is unlikely to crash due to alignment but should be improved
-		I2NPHeader * header = (I2NPHeader *)buf;
-		switch (header->typeID)
+		uint8_t typeID = buf[I2NP_HEADER_TYPEID_OFFSET];
+		switch (typeID)
 		{	
 			case eI2NPData:
-				HandleDataMessage (buf + sizeof (I2NPHeader), be16toh (header->size));
+				HandleDataMessage (buf + I2NP_HEADER_SIZE, bufbe16toh (buf + I2NP_HEADER_SIZE_OFFSET));
 			break;
 			case eI2NPDatabaseStore:
-				HandleDatabaseStoreMessage (buf + sizeof (I2NPHeader), be16toh (header->size));
+				HandleDatabaseStoreMessage (buf + I2NP_HEADER_SIZE, bufbe16toh (buf + I2NP_HEADER_SIZE_OFFSET));
 			break;
 			case eI2NPDatabaseSearchReply:
-				HandleDatabaseSearchReplyMessage (buf + sizeof (I2NPHeader), be16toh (header->size));
+				HandleDatabaseSearchReplyMessage (buf + I2NP_HEADER_SIZE, bufbe16toh (buf + I2NP_HEADER_SIZE_OFFSET));
 			break;	
 			default:
 				i2p::HandleI2NPMessage (CreateI2NPMessage (buf, GetI2NPMessageLength (buf), from));

I2NPProtocol.cpp

@@ -545,19 +545,18 @@ namespace i2p
 
 	size_t GetI2NPMessageLength (const uint8_t * msg)
 	{
-		I2NPHeader * header = (I2NPHeader *)msg;
-		return be16toh (header->size) + sizeof (I2NPHeader);
+		return bufbe16toh (msg + I2NP_HEADER_SIZE_OFFSET) + I2NP_HEADER_SIZE;
 	}	
 	
 	void HandleI2NPMessage (uint8_t * msg, size_t len)
 	{
-		I2NPHeader * header = (I2NPHeader *)msg;
-		uint32_t msgID = be32toh (header->msgID);	
-		LogPrint ("I2NP msg received len=", len,", type=", (int)header->typeID, ", msgID=", (unsigned int)msgID);
+		uint8_t typeID = msg[I2NP_HEADER_TYPEID_OFFSET];
+		uint32_t msgID = bufbe32toh (msg + I2NP_HEADER_MSGID_OFFSET);	
+		LogPrint ("I2NP msg received len=", len,", type=", (int)typeID, ", msgID=", (unsigned int)msgID);
 
-		uint8_t * buf = msg + sizeof (I2NPHeader);
-		int size = be16toh (header->size);
-		switch (header->typeID)
+		uint8_t * buf = msg + I2NP_HEADER_SIZE;
+		int size = bufbe16toh (msg + I2NP_HEADER_SIZE_OFFSET);
+		switch (typeID)
 		{	
 			case eI2NPVariableTunnelBuild:
 				LogPrint ("VariableTunnelBuild");
@@ -576,7 +575,7 @@ namespace i2p
 				// TODO:
 			break;	
 			default:
-				LogPrint ("Unexpected message ", (int)header->typeID);
+				LogPrint ("Unexpected message ", (int)typeID);
 		}	
 	}
 

I2NPProtocol.h

@@ -20,6 +20,11 @@ namespace i2p
 	const size_t I2NP_HEADER_CHKS_OFFSET = I2NP_HEADER_SIZE_OFFSET + 2;
 	const size_t I2NP_HEADER_SIZE = I2NP_HEADER_CHKS_OFFSET + 1;
 
+	// I2NP short header
+	const size_t I2NP_SHORT_HEADER_TYPEID_OFFSET = 0;
+	const size_t I2NP_SHORT_HEADER_EXPIRATION_OFFSET = I2NP_SHORT_HEADER_TYPEID_OFFSET + 1;
+	const size_t I2NP_SHORT_HEADER_SIZE = I2NP_SHORT_HEADER_EXPIRATION_OFFSET + 4;
+	
 	// Tunnel Gateway header
 	const size_t TUNNEL_GATEWAY_HEADER_TUNNELID_OFFSET = 0;
 	const size_t TUNNEL_GATEWAY_HEADER_LENGTH_OFFSET = TUNNEL_GATEWAY_HEADER_TUNNELID_OFFSET + 4;
@@ -27,21 +32,6 @@ namespace i2p
 	
 #pragma pack (1)
 
-	struct I2NPHeader
-	{
-		uint8_t typeID;
-		uint32_t msgID;
-		uint64_t expiration;
-		uint16_t size;
-		uint8_t chks;
-	};	
-
-	struct I2NPHeaderShort
-	{
-		uint8_t typeID;
-		uint32_t shortExpiration;
-	};	
-
 	struct I2NPDatabaseStoreMsg
 	{
 		uint8_t key[32];
@@ -118,10 +108,10 @@ namespace tunnel
 		size_t len, offset, maxLen;
 		i2p::tunnel::InboundTunnel * from;
 		
-		I2NPMessage (): buf (nullptr),len (sizeof (I2NPHeader) + 2), 
+		I2NPMessage (): buf (nullptr),len (I2NP_HEADER_SIZE + 2), 
 			offset(2), maxLen (0), from (nullptr) {}; 
 		// reserve 2 bytes for NTCP header
-		I2NPHeader * GetHeader () { return (I2NPHeader *)GetBuffer (); }; // depricated
+	//	I2NPHeader * GetHeader () { return (I2NPHeader *)GetBuffer (); }; // depricated
 		// header accessors
 		uint8_t * GetHeaderBuffer () { return GetBuffer (); };
 		const uint8_t * GetHeaderBuffer () const { return GetBuffer (); };
@@ -131,8 +121,10 @@ namespace tunnel
 		uint32_t GetMsgID () const { return bufbe32toh (GetHeaderBuffer () + I2NP_HEADER_MSGID_OFFSET); };
 		void SetExpiration (uint64_t expiration) { htobe64buf (GetHeaderBuffer () + I2NP_HEADER_EXPIRATION_OFFSET, expiration); };
 		uint64_t GetExpiration () const { return bufbe64toh (GetHeaderBuffer () + I2NP_HEADER_EXPIRATION_OFFSET); };
+		void SetSize (uint16_t size) { htobe16buf (GetHeaderBuffer () + I2NP_HEADER_SIZE_OFFSET, size); };
 		uint16_t GetSize () const { return bufbe16toh (GetHeaderBuffer () + I2NP_HEADER_SIZE_OFFSET); };
-		void UpdateSize () { htobe16buf (GetHeaderBuffer () + I2NP_HEADER_SIZE_OFFSET, GetPayloadLength ()); };	
+		void UpdateSize () { SetSize (GetPayloadLength ()); };	
+		void SetChks (uint8_t chks) { GetHeaderBuffer ()[I2NP_HEADER_CHKS_OFFSET] = chks; };
 		void UpdateChks () 
 		{
 			uint8_t hash[32];
@@ -141,11 +133,11 @@ namespace tunnel
 		}	
 		
 		// payload
-		uint8_t * GetPayload () { return GetBuffer () + sizeof(I2NPHeader); };
+		uint8_t * GetPayload () { return GetBuffer () + I2NP_HEADER_SIZE; };
 		uint8_t * GetBuffer () { return buf + offset; };
 		const uint8_t * GetBuffer () const { return buf + offset; };
 		size_t GetLength () const { return len - offset; };	
-		size_t GetPayloadLength () const { return GetLength () - sizeof(I2NPHeader); };	
+		size_t GetPayloadLength () const { return GetLength () - I2NP_HEADER_SIZE; };	
 			
 		void Align (size_t alignment) 
 		{
@@ -166,25 +158,25 @@ namespace tunnel
 		}	
 
 		// for SSU only
-		uint8_t * GetSSUHeader () { return buf + offset + sizeof(I2NPHeader) - sizeof(I2NPHeaderShort); };	
+		uint8_t * GetSSUHeader () { return buf + offset + I2NP_HEADER_SIZE - I2NP_SHORT_HEADER_SIZE; };	
 		void FromSSU (uint32_t msgID) // we have received SSU message and convert it to regular
 		{
-			I2NPHeaderShort ssu = *(I2NPHeaderShort *)GetSSUHeader ();
-			I2NPHeader * header = GetHeader ();
-			header->typeID = ssu.typeID;
-			header->msgID = htobe32 (msgID);
-			header->expiration = htobe64 (be32toh (ssu.shortExpiration)*1000LL);
-			header->size = htobe16 (len - offset - sizeof (I2NPHeader));
-			header->chks = 0;
+			const uint8_t * ssu = GetSSUHeader ();
+			GetHeaderBuffer ()[I2NP_HEADER_TYPEID_OFFSET] = ssu[I2NP_SHORT_HEADER_TYPEID_OFFSET]; // typeid
+			SetMsgID (msgID);
+			SetExpiration (bufbe32toh (ssu + I2NP_SHORT_HEADER_EXPIRATION_OFFSET)*1000LL);
+			SetSize (len - offset - I2NP_HEADER_SIZE);
+			SetChks (0);
 		}
 		uint32_t ToSSU () // return msgID
 		{
-			I2NPHeader header = *GetHeader ();
-			I2NPHeaderShort * ssu = (I2NPHeaderShort *)GetSSUHeader ();
-			ssu->typeID = header.typeID;
-			ssu->shortExpiration = htobe32 (be64toh (header.expiration)/1000LL); 
-			len = offset + sizeof (I2NPHeaderShort) + be16toh (header.size);
-			return be32toh (header.msgID);
+			uint8_t header[I2NP_HEADER_SIZE];
+			memcpy (header, GetHeaderBuffer (), I2NP_HEADER_SIZE);
+			uint8_t * ssu = GetSSUHeader ();
+			ssu[I2NP_SHORT_HEADER_TYPEID_OFFSET] = header[I2NP_HEADER_TYPEID_OFFSET]; // typeid
+			htobe32buf (ssu + I2NP_SHORT_HEADER_EXPIRATION_OFFSET, bufbe64toh (header + I2NP_HEADER_EXPIRATION_OFFSET)/1000LL);
+			len = offset + I2NP_SHORT_HEADER_SIZE + bufbe16toh (header + I2NP_HEADER_SIZE_OFFSET);
+			return bufbe32toh (header + I2NP_HEADER_MSGID_OFFSET);
 		}	
 	};	
 

NetDb.cpp

@@ -122,7 +122,7 @@ namespace data
 				{	
 					while (msg)
 					{
-						switch (msg->GetHeader ()->typeID) 
+						switch (msg->GetTypeID ()) 
 						{
 							case eI2NPDatabaseStore:	
 								LogPrint ("DatabaseStore");
@@ -137,7 +137,7 @@ namespace data
 								HandleDatabaseLookupMsg (msg);
 							break;	
 							default: // WTF?
-								LogPrint ("NetDb: unexpected message type ", msg->GetHeader ()->typeID);
+								LogPrint ("NetDb: unexpected message type ", msg->GetTypeID ());
 								i2p::HandleI2NPMessage (msg);
 						}	
 						msg = m_Queue.Get ();
@@ -424,7 +424,7 @@ namespace data
 	void NetDb::HandleDatabaseStoreMsg (I2NPMessage * m)
 	{	
 		const uint8_t * buf = m->GetPayload ();
-		size_t len = be16toh (m->GetHeader ()->size);		
+		size_t len = m->GetSize ();		
 		I2NPDatabaseStoreMsg msg;
 		memcpy (&msg, buf, sizeof (I2NPDatabaseStoreMsg));
 		size_t offset = sizeof (I2NPDatabaseStoreMsg);

SSUData.cpp

@@ -168,7 +168,7 @@ namespace transport
 			{
 				// create new message
 				msg = NewI2NPMessage ();
-				msg->len -= sizeof (I2NPHeaderShort);
+				msg->len -= I2NP_SHORT_HEADER_SIZE;
 				incompleteMessage = new IncompleteMessage (msg);
 				m_IncomleteMessages[msgID] = incompleteMessage;
 			}	
@@ -246,13 +246,13 @@ namespace transport
 				else
 				{
 					// we expect DeliveryStatus
-					if (msg->GetHeader ()->typeID == eI2NPDeliveryStatus)
+					if (msg->GetTypeID () == eI2NPDeliveryStatus)
 					{
 						LogPrint ("SSU session established");
 						m_Session.Established ();
 					}	
 					else
-						LogPrint (eLogError, "SSU unexpected message ", (int)msg->GetHeader ()->typeID);
+						LogPrint (eLogError, "SSU unexpected message ", (int)msg->GetTypeID ());
 					DeleteI2NPMessage (msg);
 				}	
 			}	
@@ -316,7 +316,7 @@ namespace transport
 			payload++;
 			*payload = 1; // always 1 message fragment per message
 			payload++;
-			htobuf32(payload, msgID);
+			*(uint32_t *)payload = msgID;
 			payload += 4;
 			bool isLast = (len <= payloadSize);
 			size_t size = isLast ? len : payloadSize;
@@ -359,7 +359,7 @@ namespace transport
 		payload++;
 		*payload = 1; // number of ACKs
 		payload++;
-		htobe32buf (payload, msgID); // msgID	
+		*(uint32_t *)(payload) = htobe32 (msgID); // msgID	
 		payload += 4;
 		*payload = 0; // number of fragments
 
@@ -382,7 +382,7 @@ namespace transport
 		*payload = 1; // number of ACK bitfields
 		payload++;
 		// one ack
-		htobe32buf (payload, msgID); // msgID	
+		*(uint32_t *)(payload) = htobe32 (msgID); // msgID	
 		payload += 4;
 		div_t d = div (fragmentNum, 7);
 		memset (payload, 0x80, d.quot); // 0x80 means non-last

TunnelEndpoint.cpp

@@ -228,7 +228,7 @@ namespace tunnel
 	
 	void TunnelEndpoint::HandleNextMessage (const TunnelMessageBlock& msg)
 	{
-		LogPrint ("TunnelMessage: handle fragment of ", msg.data->GetLength ()," bytes. Msg type ", (int)msg.data->GetHeader()->typeID);
+		LogPrint ("TunnelMessage: handle fragment of ", msg.data->GetLength ()," bytes. Msg type ", (int)msg.data->GetTypeID ());
 		switch (msg.deliveryType)
 		{
 			case eDeliveryTypeLocal:
@@ -245,8 +245,8 @@ namespace tunnel
 					// to somebody else
 					if (!m_IsInbound) // outbound transit tunnel
 					{
-						if (msg.data->GetHeader()->typeID == eI2NPDatabaseStore ||
-						    msg.data->GetHeader()->typeID == eI2NPDatabaseSearchReply )
+						auto typeID = msg.data->GetTypeID ();
+						if (typeID == eI2NPDatabaseStore || typeID == eI2NPDatabaseSearchReply )
 						{
 							// catch RI or reply with new list of routers
 							auto ds = NewI2NPMessage ();

TunnelGateway.cpp

@@ -68,7 +68,8 @@ namespace tunnel
 			if (diLen + 6 <= m_RemainingSize)
 			{
 				// delivery instructions fit
-				uint32_t msgID = msg->GetHeader ()->msgID; // in network bytes order
+				uint32_t msgID;
+				memcpy (&msgID, msg->GetHeaderBuffer () + I2NP_HEADER_MSGID_OFFSET, 4); // in network bytes order
 				size_t size = m_RemainingSize - diLen - 6; // 6 = 4 (msgID) + 2 (size)
 
 				// first fragment
@@ -134,7 +135,7 @@ namespace tunnel
 		m_CurrentTunnelDataMsg = NewI2NPMessage ();
 		m_CurrentTunnelDataMsg->Align (12);
 		// we reserve space for padding
-		m_CurrentTunnelDataMsg->offset += TUNNEL_DATA_MSG_SIZE + sizeof (I2NPHeader);
+		m_CurrentTunnelDataMsg->offset += TUNNEL_DATA_MSG_SIZE + I2NP_HEADER_SIZE;
 		m_CurrentTunnelDataMsg->len = m_CurrentTunnelDataMsg->offset;
 		m_RemainingSize = TUNNEL_DATA_MAX_PAYLOAD_SIZE;
 	}	
@@ -145,7 +146,7 @@ namespace tunnel
 		uint8_t * payload = m_CurrentTunnelDataMsg->GetBuffer ();
 		size_t size = m_CurrentTunnelDataMsg->len - m_CurrentTunnelDataMsg->offset;
 		
-		m_CurrentTunnelDataMsg->offset = m_CurrentTunnelDataMsg->len - TUNNEL_DATA_MSG_SIZE - sizeof (I2NPHeader);
+		m_CurrentTunnelDataMsg->offset = m_CurrentTunnelDataMsg->len - TUNNEL_DATA_MSG_SIZE - I2NP_HEADER_SIZE;
 		uint8_t * buf = m_CurrentTunnelDataMsg->GetPayload ();
 		htobe32buf (buf, m_TunnelID);
 		CryptoPP::RandomNumberGenerator& rnd = i2p::context.GetRandomNumberGenerator ();