Avoid aliasing problems by using special buf endian handling functions wrapping memcpy

Destination.cpp

@@ -357,7 +357,7 @@ namespace client
 
 	void ClientDestination::HandleDataMessage (const uint8_t * buf, size_t len)
 	{
-		uint32_t length = be32toh (*(uint32_t *)buf);
+		uint32_t length = bufbe32toh (buf);
 		buf += 4;
 		// we assume I2CP payload
 		switch (buf[9])

Garlic.cpp

@@ -331,7 +331,7 @@ namespace garlic
 	void GarlicDestination::HandleGarlicMessage (I2NPMessage * msg)
 	{
 		uint8_t * buf = msg->GetPayload ();
-		uint32_t length = be32toh (*(uint32_t *)buf);
+		uint32_t length = bufbe32toh (buf);
 		buf += 4; // length
 		auto it = m_Tags.find (SessionTag(buf));
 		if (it != m_Tags.end ())
@@ -389,7 +389,7 @@ namespace garlic
 	void GarlicDestination::HandleAESBlock (uint8_t * buf, size_t len, std::shared_ptr<i2p::crypto::CBCDecryption> decryption,
 		i2p::tunnel::InboundTunnel * from)
 	{
-		uint16_t tagCount = be16toh (*(uint16_t *)buf);
+		uint16_t tagCount = bufbe16toh (buf);
 		buf += 2; len -= 2;	
 		if (tagCount > 0)
 		{	
@@ -404,7 +404,7 @@ namespace garlic
 		}	
 		buf += tagCount*32;
 		len -= tagCount*32;
-		uint32_t payloadSize = be32toh (*(uint32_t *)buf);
+		uint32_t payloadSize = bufbe32toh (buf);
 		if (payloadSize > len)
 		{
 			LogPrint (eLogError, "Unexpected payload size ", payloadSize);
@@ -460,7 +460,7 @@ namespace garlic
 					// gwHash and gwTunnel sequence is reverted
 					uint8_t * gwHash = buf;
 					buf += 32;
-					uint32_t gwTunnel = be32toh (*(uint32_t *)buf);
+					uint32_t gwTunnel = bufbe32toh (buf);
 					buf += 4;
 					i2p::tunnel::OutboundTunnel * tunnel = nullptr;
 					if (from && from->GetTunnelPool ())

I2PEndian.cpp

@@ -5,6 +5,7 @@
 
 #include "LittleBigEndian.h"
 
+#ifdef NEEDS_LOCAL_ENDIAN
 uint16_t htobe16(uint16_t int16)
 {
 	BigEndian<uint16_t> u16(int16);
@@ -40,6 +41,7 @@ uint64_t be64toh(uint64_t big64)
 	LittleEndian<uint64_t> u64(big64);
 	return u64.raw_value;
 }
+#endif
 
 /* it can be used in Windows 8
 #include <Winsock2.h>

I2PEndian.h

@@ -1,5 +1,7 @@
 #ifndef I2PENDIAN_H__
 #define I2PENDIAN_H__
+#include <inttypes.h>
+#include <cstring>
 
 #if defined(__linux__) || defined(__FreeBSD_kernel__)
 #include <endian.h>
@@ -25,6 +27,7 @@
 #define le64toh(x) OSSwapLittleToHostInt64(x)
 
 #else
+#define NEEDS_LOCAL_ENDIAN
 #include <cstdint>
 uint16_t htobe16(uint16_t int16);
 uint32_t htobe32(uint32_t int32);
@@ -44,5 +47,27 @@ uint64_t be64toh(uint64_t big64);
 
 #endif
 
+inline uint16_t bufbe16toh(const uint8_t *buf)
+{
+	uint16_t big16;
+	memcpy(&big16, buf, sizeof(uint16_t));
+	return be16toh(big16);
+}
+
+inline uint32_t bufbe32toh(const uint8_t *buf)
+{
+	uint32_t big32;
+	memcpy(&big32, buf, sizeof(uint32_t));
+	return be32toh(big32);
+}
+
+inline uint64_t bufbe64toh(const uint8_t *buf)
+{
+	uint64_t big64;
+	memcpy(&big64, buf, sizeof(uint64_t));
+	return be64toh(big64);
+}
+
+
 #endif // I2PENDIAN_H__
 

Identity.cpp

@@ -275,14 +275,14 @@ namespace data
 	SigningKeyType IdentityEx::GetSigningKeyType () const
 	{
 		if (m_StandardIdentity.certificate.type == CERTIFICATE_TYPE_KEY && m_ExtendedBuffer)				
-			return be16toh (*(const uint16_t *)m_ExtendedBuffer); // signing key
+			return bufbe16toh (m_ExtendedBuffer); // signing key
 		return SIGNING_KEY_TYPE_DSA_SHA1;
 	}	
 
 	CryptoKeyType IdentityEx::GetCryptoKeyType () const
 	{
 		if (m_StandardIdentity.certificate.type == CERTIFICATE_TYPE_KEY && m_ExtendedBuffer)				
-			return be16toh (*(const uint16_t *)(m_ExtendedBuffer + 2)); // crypto key
+			return bufbe16toh (m_ExtendedBuffer + 2); // crypto key
 		return CRYPTO_KEY_TYPE_ELGAMAL;
 	}	
 		

NTCPSession.cpp

@@ -338,7 +338,7 @@ namespace transport
 			LogPrint (eLogDebug, "Phase 3 received: ", bytes_transferred);
 			m_Decryption.Decrypt (m_ReceiveBuffer, bytes_transferred, m_ReceiveBuffer);
 			uint8_t * buf = m_ReceiveBuffer;
-			uint16_t size = be16toh (*(uint16_t *)buf);
+			uint16_t size = bufbe16toh (buf);
 			m_RemoteIdentity.FromBuffer (buf + 2, size);
 			size_t expectedSize = size + 2/*size*/ + 4/*timestamp*/ + m_RemoteIdentity.GetSignatureLen ();
 			size_t paddingLen = expectedSize & 0x0F;
@@ -526,7 +526,7 @@ namespace transport
 			m_NextMessageOffset = 0;
 			
 			m_Decryption.Decrypt (encrypted, m_NextMessage->buf);
-			uint16_t dataSize = be16toh (*(uint16_t *)m_NextMessage->buf);
+			uint16_t dataSize = bufbe16toh (m_NextMessage->buf);
 			if (dataSize)
 			{
 				// new message

NetDb.cpp

@@ -436,7 +436,7 @@ namespace data
 		else
 		{
 			LogPrint ("RouterInfo");
-			size_t size = be16toh (*(uint16_t *)(buf + offset));
+			size_t size = bufbe16toh (buf + offset);
 			if (size > 2048)
 			{
 				LogPrint ("Invalid RouterInfo length ", (int)size);
@@ -597,10 +597,10 @@ namespace data
 		uint32_t replyTunnelID = 0;
 		if (flag & 0x01) //reply to tunnel
 		{
-			replyTunnelID = be32toh (*(uint32_t *)(buf + 64));
+			replyTunnelID = bufbe32toh (buf + 64);
 			excluded += 4;
 		}
-		uint16_t numExcluded = be16toh (*(uint16_t *)excluded);	
+		uint16_t numExcluded = bufbe16toh (excluded);	
 		excluded += 2;
 		if (numExcluded > 512)
 		{

SSUData.cpp

@@ -84,7 +84,7 @@ namespace transport
 			uint8_t numAcks =*buf;
 			buf++;
 			for (int i = 0; i < numAcks; i++)
-				ProcessSentMessageAck (be32toh (((uint32_t *)buf)[i]));
+				ProcessSentMessageAck (bufbe32toh (buf+i*4));
 			buf += numAcks*4;
 		}
 		if (flag & DATA_FLAG_ACK_BITFIELDS_INCLUDED)
@@ -94,7 +94,7 @@ namespace transport
 			buf++;
 			for (int i = 0; i < numBitfields; i++)
 			{
-				uint32_t msgID = be32toh (*(uint32_t *)buf);
+				uint32_t msgID = bufbe32toh (buf);
 				buf += 4; // msgID
 				auto it = m_SentMessages.find (msgID);		
 				// process individual Ack bitfields
@@ -137,13 +137,13 @@ namespace transport
 		buf++;
 		for (int i = 0; i < numFragments; i++)
 		{	
-			uint32_t msgID = be32toh (*(uint32_t *)buf); // message ID
+			uint32_t msgID = bufbe32toh (buf); // message ID
 			buf += 4;
 			uint8_t frag[4];
 			frag[0] = 0;
 			memcpy (frag + 1, buf, 3);
 			buf += 3;
-			uint32_t fragmentInfo = be32toh (*(uint32_t *)frag); // fragment info
+			uint32_t fragmentInfo = bufbe32toh (frag); // fragment info
 			uint16_t fragmentSize = fragmentInfo & 0x1FFF; // bits 0 - 13
 			bool isLast = fragmentInfo & 0x010000; // bit 16	
 			uint8_t fragmentNum = fragmentInfo >> 17; // bits 23 - 17

SSUSession.cpp

@@ -210,7 +210,7 @@ namespace transport
 		}	
 		s.Insert (ourAddress, addressSize); // our IP 
 		payload += addressSize; // address
-		uint16_t ourPort = be16toh (*(uint16_t *)payload);
+		uint16_t ourPort = bufbe16toh (payload);
 		s.Insert (payload, 2); // our port
 		payload += 2; // port
 		LogPrint ("Our external address is ", ourIP.to_string (), ":", ourPort);
@@ -221,7 +221,7 @@ namespace transport
 			s.Insert (m_RemoteEndpoint.address ().to_v6 ().to_bytes ().data (), 16); // remote IP v6
 		s.Insert (htobe16 (m_RemoteEndpoint.port ())); // remote port
 		s.Insert (payload, 8); // relayTag and signed on time 
-		m_RelayTag = be32toh (*(uint32_t *)payload);
+		m_RelayTag = bufbe32toh (payload);
 		payload += 4; // relayTag
 		payload += 4; // signed on time
 		// decrypt signature
@@ -242,7 +242,7 @@ namespace transport
 		LogPrint (eLogDebug, "Session confirmed received");	
 		uint8_t * payload = buf + sizeof (SSUHeader);
 		payload++; // identity fragment info
-		uint16_t identitySize = be16toh (*(uint16_t *)payload);	
+		uint16_t identitySize = bufbe16toh (payload);	
 		payload += 2; // size of identity fragment
 		m_RemoteIdentity.FromBuffer (payload, identitySize);
 		m_Data.UpdatePacketSize (m_RemoteIdentity.GetIdentHash ());
@@ -443,7 +443,7 @@ namespace transport
 
 	void SSUSession::ProcessRelayRequest (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& from)
 	{
-		uint32_t relayTag = be32toh (*(uint32_t *)buf);
+		uint32_t relayTag = bufbe32toh (buf);
 		auto session = m_Server.FindRelaySession (relayTag);
 		if (session)
 		{
@@ -457,7 +457,7 @@ namespace transport
 			buf += challengeSize;
 			uint8_t * introKey = buf;
 			buf += 32; // introkey
-			uint32_t nonce = be32toh (*(uint32_t *)buf);
+			uint32_t nonce = bufbe32toh (buf);
 			SendRelayResponse (nonce, from, introKey, session->m_RemoteEndpoint);
 			SendRelayIntro (session.get (), from);
 		}	
@@ -550,9 +550,9 @@ namespace transport
 		uint8_t * payload = buf + sizeof (SSUHeader);
 		uint8_t remoteSize = *payload; 
 		payload++; // remote size
-		//boost::asio::ip::address_v4 remoteIP (be32toh (*(uint32_t* )(payload)));
+		//boost::asio::ip::address_v4 remoteIP (bufbe32toh (payload));
 		payload += remoteSize; // remote address
-		//uint16_t remotePort = be16toh (*(uint16_t *)(payload));
+		//uint16_t remotePort = bufbe16toh (payload);
 		payload += 2; // remote port
 		uint8_t ourSize = *payload; 
 		payload++; // our size
@@ -570,7 +570,7 @@ namespace transport
 			ourIP = boost::asio::ip::address_v6 (bytes);
 		}
 		payload += ourSize; // our address
-		uint16_t ourPort = be16toh (*(uint16_t *)(payload));
+		uint16_t ourPort = bufbe16toh (payload);
 		payload += 2; // our port
 		LogPrint ("Our external address is ", ourIP.to_string (), ":", ourPort);
 		i2p::context.UpdateAddress (ourIP);
@@ -582,9 +582,9 @@ namespace transport
 		if (size == 4)
 		{
 			buf++; // size
-			boost::asio::ip::address_v4 address (be32toh (*(uint32_t* )buf));
+			boost::asio::ip::address_v4 address (bufbe32toh (buf));
 			buf += 4; // address
-			uint16_t port = be16toh (*(uint16_t *)buf);
+			uint16_t port = bufbe16toh (buf);
 			// send hole punch of 1 byte
 			m_Server.Send (buf, 0, boost::asio::ip::udp::endpoint (address, port));
 		}
@@ -844,10 +844,11 @@ namespace transport
 	void SSUSession::ProcessPeerTest (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& senderEndpoint)
 	{
 		uint8_t * buf1 = buf;
-		uint32_t nonce = be32toh (*(uint32_t *)buf);
+		uint32_t nonce = bufbe32toh (buf);
 		buf += 4; // nonce
 		uint8_t size = *buf;
 		buf++; // size
+		
 		uint32_t address = (size == 4) ? *(uint32_t *)buf : 0; // use it as is
 		buf += size; // address
 		uint16_t port = *(uint16_t *)buf; // use it as is

Streaming.cpp

@@ -167,7 +167,7 @@ namespace stream
 
 		if (flags & PACKET_FLAG_MAX_PACKET_SIZE_INCLUDED)
 		{
-			uint16_t maxPacketSize = be16toh (*(uint16_t *)optionData);
+			uint16_t maxPacketSize = bufbe16toh (optionData);
 			LogPrint (eLogDebug, "Max packet size ", maxPacketSize);
 			optionData += 2;
 		}	

Streaming.h

@@ -53,15 +53,15 @@ namespace stream
 		uint8_t * GetBuffer () { return buf + offset; };
 		size_t GetLength () const { return len - offset; };
 
-		uint32_t GetSendStreamID () const { return be32toh (*(uint32_t *)buf); };
-		uint32_t GetReceiveStreamID () const { return be32toh (*(uint32_t *)(buf + 4)); };
-		uint32_t GetSeqn () const { return be32toh (*(uint32_t *)(buf + 8)); };
-		uint32_t GetAckThrough () const { return be32toh (*(uint32_t *)(buf + 12)); };
+		uint32_t GetSendStreamID () const { return bufbe32toh (buf); };
+		uint32_t GetReceiveStreamID () const { return bufbe32toh (buf + 4); };
+		uint32_t GetSeqn () const { return bufbe32toh (buf + 8); };
+		uint32_t GetAckThrough () const { return bufbe32toh (buf + 12); };
 		uint8_t GetNACKCount () const { return buf[16]; };
-		uint32_t GetNACK (int i) const { return be32toh (((uint32_t *)(buf + 17))[i]); };
+		uint32_t GetNACK (int i) const { return bufbe32toh (buf + 17 + 4 * i); };
 		const uint8_t * GetOption () const { return buf + 17 + GetNACKCount ()*4 + 3; }; // 3 = resendDelay + flags
-		uint16_t GetFlags () const { return be16toh (*(uint16_t *)(GetOption () - 2)); };
-		uint16_t GetOptionSize () const { return be16toh (*(uint16_t *)GetOption ()); };
+		uint16_t GetFlags () const { return bufbe16toh (GetOption () - 2); };
+		uint16_t GetOptionSize () const { return bufbe16toh (GetOption ()); };
 		const uint8_t * GetOptionData () const { return GetOption () + 2; };
 		const uint8_t * GetPayload () const { return GetOptionData () + GetOptionSize (); };
 

Tunnel.cpp

@@ -356,7 +356,7 @@ namespace tunnel
 				I2NPMessage * msg = m_Queue.GetNextWithTimeout (1000); // 1 sec
 				while (msg)
 				{
-					uint32_t  tunnelID = be32toh (*(uint32_t *)msg->GetPayload ()); 
+					uint32_t  tunnelID = bufbe32toh (msg->GetPayload ()); 
 					InboundTunnel * tunnel = GetInboundTunnel (tunnelID);
 					if (tunnel)
 						tunnel->HandleTunnelDataMsg (msg);

TunnelEndpoint.cpp

@@ -61,7 +61,7 @@ namespace tunnel
 						break;
 					  	case eDeliveryTypeTunnel: // 1
 							LogPrint ("Delivery type tunnel");	
-							m.tunnelID = be32toh (*(uint32_t *)fragment);
+							m.tunnelID = bufbe32toh (fragment);
 							fragment += 4; // tunnelID
 							m.hash = i2p::data::IdentHash (fragment);
 							fragment += 32; // hash
@@ -79,7 +79,7 @@ namespace tunnel
 					if (isFragmented)
 					{
 						// Message ID
-						msgID = be32toh (*(uint32_t *)fragment); 	
+						msgID = bufbe32toh (fragment); 	
 						fragment += 4;
 						LogPrint ("Fragmented message ", msgID);
 						isLastFragment = false;
@@ -88,14 +88,14 @@ namespace tunnel
 				else
 				{
 					// follow on
-					msgID = be32toh (*(uint32_t *)fragment); // MessageID			
+					msgID = bufbe32toh (fragment); // MessageID			
 					fragment += 4; 
 					fragmentNum = (flag >> 1) & 0x3F; // 6 bits
 					isLastFragment = flag & 0x01;
 					LogPrint ("Follow on fragment ", fragmentNum, " of message ", msgID, isLastFragment ? " last" : " non-last");
 				}	
 				
-				uint16_t size = be16toh (*(uint16_t *)fragment);
+				uint16_t size = bufbe16toh (fragment);
 				fragment += 2;
 				LogPrint ("Fragment size=", (int)size);