From 3c8f859169cb3c51807a814ae2e336c2ae124c5b Mon Sep 17 00:00:00 2001
From: orignal <romakoshelkin@yandex.ru>
Date: Thu, 20 Feb 2014 20:28:41 -0500
Subject: [PATCH] replaced ElGamalEncrypt to ElGamalEncryption

---
 ElGamal.h        | 32 ++++----------------------------
 Garlic.cpp       |  5 ++---
 Garlic.h         |  2 --
 I2NPProtocol.cpp |  2 +-
 Identity.h       | 16 ++++++++++++++++
 5 files changed, 23 insertions(+), 34 deletions(-)

diff --git a/ElGamal.h b/ElGamal.h
index 745c3840..b3f0e44f 100644
--- a/ElGamal.h
+++ b/ElGamal.h
@@ -17,14 +17,13 @@ namespace crypto
 	{
 		public:
 
-			ElGamalEncryption (const uint8_t * key, bool zeroPadding = false):
+			ElGamalEncryption (const uint8_t * key):
 				y (key, 256), k (rnd, CryptoPP::Integer::One(), elgp-1),
-				a (a_exp_b_mod_c (elgg, k, elgp)), b1 (a_exp_b_mod_c (y, k, elgp)), 
-				m_ZeroPadding (zeroPadding)
+				a (a_exp_b_mod_c (elgg, k, elgp)), b1 (a_exp_b_mod_c (y, k, elgp))
 			{
 			}
 
-			void Encrypt (const uint8_t * data, int len, uint8_t * encrypted)
+			void Encrypt (const uint8_t * data, int len, uint8_t * encrypted, bool zeroPadding = false)
 			{
 				// calculate b = b1*m mod p
 				uint8_t m[255];
@@ -34,7 +33,7 @@ namespace crypto
 				CryptoPP::Integer b (a_times_b_mod_c (b1, CryptoPP::Integer (m, 255), elgp));
 
 				// copy a and b
-				if (m_ZeroPadding)
+				if (zeroPadding)
 				{
 					encrypted[0] = 0;
 					a.Encode (encrypted + 1, 256);
@@ -72,29 +71,6 @@ namespace crypto
 		memcpy (data, m + 33, 222);
 		return true;
 	}	
-
-
-// deprecated
-
-	inline void ElGamalEncrypt (const uint8_t * key, const uint8_t * data, int len, 
-		uint8_t * encrypted, bool zeroPadding = false) // 514 with padding and 512 without
-	{
-		CryptoPP::AutoSeededRandomPool rnd;		
-		CryptoPP::Integer y(key, 256), k(rnd, CryptoPP::Integer::One(), elgp-1);
-
-		if (zeroPadding)
-		{
-			encrypted[0] = 0;
-			encrypted[257] = 0;
-		}	
-		a_exp_b_mod_c (elgg, k, elgp).Encode (zeroPadding ? encrypted + 1 : encrypted, 256);
-		uint8_t m[255];
-		m[0] = 0xFF;
-		memcpy (m+33, data, len);
-		CryptoPP::SHA256().CalculateDigest(m+1, m+33, 222);
-		a_times_b_mod_c (a_exp_b_mod_c (y, k, elgp), 
-			CryptoPP::Integer (m, 255), elgp).Encode (zeroPadding ? encrypted + 258 : encrypted + 256, 256);
-	}	
 }
 }	
 
diff --git a/Garlic.cpp b/Garlic.cpp
index 80a267c7..e73a6f02 100644
--- a/Garlic.cpp
+++ b/Garlic.cpp
@@ -15,8 +15,7 @@ namespace garlic
 {	
 	GarlicRoutingSession::GarlicRoutingSession (const i2p::data::RoutingDestination& destination, int numTags):
 		m_Destination (destination), m_FirstMsgID (0), m_IsAcknowledged (false), 
-		m_NumTags (numTags), m_NextTag (-1), m_SessionTags (0),
-		m_ElGamalEncryption (m_Destination.GetEncryptionPublicKey (), true)
+		m_NumTags (numTags), m_NextTag (-1), m_SessionTags (0)
 	{
 		// create new session tags and session key
 		m_Rnd.GenerateBlock (m_SessionKey, 32);
@@ -56,7 +55,7 @@ namespace garlic
 			m_Rnd.GenerateBlock (elGamal.preIV, 32); // Pre-IV
 			uint8_t iv[32]; // IV is first 16 bytes
 			CryptoPP::SHA256().CalculateDigest(iv, elGamal.preIV, 32); 
-			m_ElGamalEncryption.Encrypt ((uint8_t *)&elGamal, sizeof(elGamal), buf);			
+			m_Destination.GetElGamalEncryption ()->Encrypt ((uint8_t *)&elGamal, sizeof(elGamal), buf, true);			
 			m_Encryption.SetKeyWithIV (m_SessionKey, 32, iv);
 			buf += 514;
 			len += 514;	
diff --git a/Garlic.h b/Garlic.h
index ca6bae64..0383b030 100644
--- a/Garlic.h
+++ b/Garlic.h
@@ -9,7 +9,6 @@
 #include <cryptopp/osrng.h>
 #include "I2NPProtocol.h"
 #include "LeaseSet.h"
-#include "ElGamal.h"
 
 namespace i2p
 {	
@@ -66,7 +65,6 @@ namespace garlic
 			uint8_t * m_SessionTags; // m_NumTags*32 bytes
 			
 			CryptoPP::CBC_Mode<CryptoPP::AES>::Encryption m_Encryption;
-			i2p::crypto::ElGamalEncryption m_ElGamalEncryption;
 			CryptoPP::AutoSeededRandomPool m_Rnd;
 	};	
 
diff --git a/I2NPProtocol.cpp b/I2NPProtocol.cpp
index f42d9f9d..25549a09 100644
--- a/I2NPProtocol.cpp
+++ b/I2NPProtocol.cpp
@@ -212,7 +212,7 @@ namespace i2p
 		const I2NPBuildRequestRecordClearText& clearText,
 	    I2NPBuildRequestRecordElGamalEncrypted& record)
 	{
-		i2p::crypto::ElGamalEncrypt (router.GetRouterIdentity ().publicKey, (uint8_t *)&clearText, sizeof(clearText), record.encrypted);
+		router.GetElGamalEncryption ()->Encrypt ((uint8_t *)&clearText, sizeof(clearText), record.encrypted);
 		memcpy (record.toPeer, (const uint8_t *)router.GetIdentHash (), 16);
 	}	
 	
diff --git a/Identity.h b/Identity.h
index e17b27be..10af227c 100644
--- a/Identity.h
+++ b/Identity.h
@@ -3,6 +3,7 @@
 
 #include <inttypes.h>
 #include <string.h>
+#include "ElGamal.h"
 
 namespace i2p
 {
@@ -84,9 +85,24 @@ namespace data
 	class RoutingDestination
 	{
 		public:
+
+			RoutingDestination (): m_ElGamalEncryption (nullptr) {};
+			virtual ~RoutingDestination () { delete m_ElGamalEncryption; };
+			
 			virtual const IdentHash& GetIdentHash () const = 0;
 			virtual const uint8_t * GetEncryptionPublicKey () const = 0;
 			virtual bool IsDestination () const = 0; // for garlic 
+
+			i2p::crypto::ElGamalEncryption * GetElGamalEncryption () const
+			{
+				if (!m_ElGamalEncryption)
+					m_ElGamalEncryption = new i2p::crypto::ElGamalEncryption (GetEncryptionPublicKey ());
+				return m_ElGamalEncryption;
+			}
+			
+		private:
+
+			mutable i2p::crypto::ElGamalEncryption * m_ElGamalEncryption; // use lazy initialization
 	};	
 }
 }