extract ret code per hop

libi2pd/Tunnel.cpp

@@ -103,26 +103,22 @@ namespace tunnel
 	{
 		LogPrint (eLogDebug, "Tunnel: TunnelBuildResponse ", (int)msg[0], " records.");
 
-		i2p::crypto::CBCDecryption decryption;
 		TunnelHopConfig * hop = m_Config->GetLastHop ();
 		while (hop)
 		{
 			// decrypt current hop
-			auto idx = hop->recordIndex;
-			if (idx >= 0 && idx < msg[0])
+			if (hop->recordIndex >= 0 && hop->recordIndex < msg[0])
 			{
-				uint8_t * record = msg + 1 + idx*TUNNEL_BUILD_RECORD_SIZE;
-				if (!hop->DecryptBuildResponseRecord (record, record))
+				if (!hop->DecryptBuildResponseRecord (msg + 1))
 					return false;
 			}	
 			else
 			{
-				LogPrint (eLogWarning, "Tunnel: hop index ", idx, " is out of range");
+				LogPrint (eLogWarning, "Tunnel: hop index ", hop->recordIndex, " is out of range");
 				return false;
 			}	
 			
 			// decrypt records before current hop 
-			decryption.SetKey (hop->replyKey);
 			TunnelHopConfig * hop1 = hop->prev;
 			while (hop1)
 			{
@@ -140,8 +136,7 @@ namespace tunnel
 		hop = m_Config->GetFirstHop ();
 		while (hop)
 		{
-			const uint8_t * record = msg + 1 + hop->recordIndex*TUNNEL_BUILD_RECORD_SIZE;
-			uint8_t ret = record[hop->IsECIES () ? ECIES_BUILD_RESPONSE_RECORD_RET_OFFSET : BUILD_RESPONSE_RECORD_RET_OFFSET];
+			uint8_t ret = hop->GetRetCode (msg + 1);
 			LogPrint (eLogDebug, "Tunnel: Build response ret code=", (int)ret);
 			auto profile = i2p::data::netdb.FindRouterProfile (hop->ident->GetIdentHash ());
 			if (profile)

libi2pd/TunnelConfig.cpp

@@ -113,12 +113,13 @@ namespace tunnel
 		memcpy (record + BUILD_REQUEST_RECORD_TO_PEER_OFFSET, (const uint8_t *)ident->GetIdentHash (), 16);
 	}	
 
-	bool ElGamalTunnelHopConfig::DecryptBuildResponseRecord (const uint8_t * encrypted, uint8_t * clearText) const
+	bool ElGamalTunnelHopConfig::DecryptBuildResponseRecord (uint8_t * records) const
 	{
+		uint8_t * record = records + recordIndex*TUNNEL_BUILD_RECORD_SIZE;
 		i2p::crypto::CBCDecryption decryption;
 		decryption.SetKey (replyKey);
 		decryption.SetIV (replyIV);
-		decryption.Decrypt (encrypted, TUNNEL_BUILD_RECORD_SIZE, clearText);
+		decryption.Decrypt (record, TUNNEL_BUILD_RECORD_SIZE, record);
 		return true;
 	}	
 
@@ -176,11 +177,12 @@ namespace tunnel
 		memcpy (record + BUILD_REQUEST_RECORD_TO_PEER_OFFSET, (const uint8_t *)ident->GetIdentHash (), 16);
 	}
 
-	bool LongECIESTunnelHopConfig::DecryptBuildResponseRecord (const uint8_t * encrypted, uint8_t * clearText) const
+	bool LongECIESTunnelHopConfig::DecryptBuildResponseRecord (uint8_t * records) const
 	{
+		uint8_t * record = records + recordIndex*TUNNEL_BUILD_RECORD_SIZE;
 		uint8_t nonce[12];
 		memset (nonce, 0, 12);
-		if (!DecryptECIES (m_CK, nonce, encrypted, TUNNEL_BUILD_RECORD_SIZE, clearText))
+		if (!DecryptECIES (m_CK, nonce, record, TUNNEL_BUILD_RECORD_SIZE, record))
 		{
 			LogPrint (eLogWarning, "Tunnel: Response AEAD decryption failed");
 			return false;
@@ -223,12 +225,13 @@ namespace tunnel
 		memcpy (record + BUILD_REQUEST_RECORD_TO_PEER_OFFSET, (const uint8_t *)ident->GetIdentHash (), 16);
 	}
 	
-	bool ShortECIESTunnelHopConfig::DecryptBuildResponseRecord (const uint8_t * encrypted, uint8_t * clearText) const
+	bool ShortECIESTunnelHopConfig::DecryptBuildResponseRecord (uint8_t * records) const
 	{
+		uint8_t * record = records + recordIndex*SHORT_TUNNEL_BUILD_RECORD_SIZE;
 		uint8_t nonce[12];
 		memset (nonce, 0, 12);
 		nonce[4] = recordIndex; // nonce is record index
-		if (!DecryptECIES (replyKey, nonce, encrypted, SHORT_TUNNEL_BUILD_RECORD_SIZE, clearText))
+		if (!DecryptECIES (replyKey, nonce, record, SHORT_TUNNEL_BUILD_RECORD_SIZE, record))
 		{
 			LogPrint (eLogWarning, "Tunnel: Response AEAD decryption failed");
 			return false;

libi2pd/TunnelConfig.h

@@ -40,9 +40,9 @@ namespace tunnel
 		void SetNext (TunnelHopConfig * n);
 		void SetPrev (TunnelHopConfig * p);		
 
-		virtual bool IsECIES () const { return false; };
+		virtual uint8_t GetRetCode (const uint8_t * records) const = 0;
 		virtual void CreateBuildRequestRecord (uint8_t * record, uint32_t replyMsgID, BN_CTX * ctx) = 0;
-		virtual bool DecryptBuildResponseRecord (const uint8_t * encrypted, uint8_t * clearText) const = 0;
+		virtual bool DecryptBuildResponseRecord (uint8_t * records) const = 0;
 		virtual void DecryptRecord (uint8_t * records, int index) const; // AES
 	};
 
@@ -50,15 +50,16 @@ namespace tunnel
 	{
 		ElGamalTunnelHopConfig (std::shared_ptr<const i2p::data::IdentityEx> r):
 			TunnelHopConfig (r) {};
+		uint8_t GetRetCode (const uint8_t * records) const 
+		{ return (records + recordIndex*TUNNEL_BUILD_RECORD_SIZE)[BUILD_RESPONSE_RECORD_RET_OFFSET]; };	
 		void CreateBuildRequestRecord (uint8_t * record, uint32_t replyMsgID, BN_CTX * ctx);	
-		bool DecryptBuildResponseRecord (const uint8_t * encrypted, uint8_t * clearText) const;	
+		bool DecryptBuildResponseRecord (uint8_t * records) const;	
 	};	
 
 	struct ECIESTunnelHopConfig: public TunnelHopConfig, public i2p::crypto::NoiseSymmetricState
 	{
 		ECIESTunnelHopConfig (std::shared_ptr<const i2p::data::IdentityEx> r):
 			TunnelHopConfig (r) {};
-		bool IsECIES () const { return true; };	
 		void EncryptECIES (const uint8_t * clearText, size_t len, uint8_t * encrypted);	
 		bool DecryptECIES (const uint8_t * key, const uint8_t * nonce, const uint8_t * encrypted, size_t len, uint8_t * clearText) const;
 	};
@@ -67,16 +68,20 @@ namespace tunnel
 	{
 		LongECIESTunnelHopConfig (std::shared_ptr<const i2p::data::IdentityEx> r):
 			ECIESTunnelHopConfig (r) {};
+		uint8_t GetRetCode (const uint8_t * records) const 
+		{ return (records + recordIndex*TUNNEL_BUILD_RECORD_SIZE)[ECIES_BUILD_RESPONSE_RECORD_RET_OFFSET]; };		
 		void CreateBuildRequestRecord (uint8_t * record, uint32_t replyMsgID, BN_CTX * ctx);
-		bool DecryptBuildResponseRecord (const uint8_t * encrypted, uint8_t * clearText) const;		
+		bool DecryptBuildResponseRecord (uint8_t * records) const;		
 	};	
 
 	struct ShortECIESTunnelHopConfig: public ECIESTunnelHopConfig
 	{
 		ShortECIESTunnelHopConfig (std::shared_ptr<const i2p::data::IdentityEx> r):
 			ECIESTunnelHopConfig (r) {};
+		uint8_t GetRetCode (const uint8_t * records) const 
+		{ return (records + recordIndex*SHORT_TUNNEL_BUILD_RECORD_SIZE)[ECIES_BUILD_RESPONSE_RECORD_RET_OFFSET]; }; // TODO			
 		void CreateBuildRequestRecord (uint8_t * record, uint32_t replyMsgID, BN_CTX * ctx);
-		bool DecryptBuildResponseRecord (const uint8_t * encrypted, uint8_t * clearText) const;	
+		bool DecryptBuildResponseRecord (uint8_t * records) const;	
 		void DecryptRecord (uint8_t * records, int index) const override; // Chacha20
 	};