removed ElGamal encryption support for own router

libi2pd/Crypto.cpp

@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2013-2020, The PurpleI2P Project
+* Copyright (c) 2013-2021, The PurpleI2P Project
 *
 * This file is part of Purple i2pd project and licensed under BSD3
 *
@@ -452,14 +452,14 @@ namespace crypto
 	}
 
 	bool ElGamalDecrypt (const uint8_t * key, const uint8_t * encrypted, 
-		uint8_t * data, BN_CTX * ctx, bool zeroPadding)
+		uint8_t * data, BN_CTX * ctx)
 	{
 		BN_CTX_start (ctx);
 		BIGNUM * x = BN_CTX_get (ctx), * a = BN_CTX_get (ctx), * b = BN_CTX_get (ctx);
 		BN_bin2bn (key, 256, x);
 		BN_sub (x, elgp, x); BN_sub_word (x, 1); // x = elgp - x- 1
-		BN_bin2bn (zeroPadding ? encrypted + 1 : encrypted, 256, a);
-		BN_bin2bn (zeroPadding ? encrypted + 258 : encrypted + 256, 256, b);
+		BN_bin2bn (encrypted + 1, 256, a);
+		BN_bin2bn (encrypted + 258, 256, b);
 		// m = b*(a^x mod p) mod p
 		BN_mod_exp (x, a, x, elgp, ctx);
 		BN_mod_mul (b, b, x, elgp, ctx);
@@ -552,7 +552,7 @@ namespace crypto
 		BN_CTX_end (ctx);
 	}
 
-	bool ECIESDecrypt (const EC_GROUP * curve, const BIGNUM * key, const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx, bool zeroPadding)
+	bool ECIESDecrypt (const EC_GROUP * curve, const BIGNUM * key, const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx)
 	{
 		bool ret = true;
 		BN_CTX_start (ctx);
@@ -561,16 +561,8 @@ namespace crypto
 		int len = BN_num_bytes (q);
 		// point for shared secret
 		BIGNUM * x = BN_CTX_get (ctx), * y = BN_CTX_get (ctx);
-		if (zeroPadding)
-		{
 		BN_bin2bn (encrypted + 1, len, x);
 		BN_bin2bn (encrypted + 1 + len, len, y);
-		}
-		else
-		{
-			BN_bin2bn (encrypted, len, x);
-			BN_bin2bn (encrypted + len, len, y);
-		}
 		auto p = EC_POINT_new (curve);
 		if (EC_POINT_set_affine_coordinates_GFp (curve, p, x, y, nullptr))
 		{
@@ -587,10 +579,7 @@ namespace crypto
 			CBCDecryption decryption;
 			decryption.SetKey (shared);
 			decryption.SetIV (iv);
-			if (zeroPadding)
 			decryption.Decrypt (encrypted + 258, 256, m);
-			else
-				decryption.Decrypt (encrypted + 256, 256, m);
 			// verify and copy
 			uint8_t hash[32];
 			SHA256 (m + 33, 222, hash);

libi2pd/Crypto.h

@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2013-2020, The PurpleI2P Project
+* Copyright (c) 2013-2021, The PurpleI2P Project
 *
 * This file is part of Purple i2pd project and licensed under BSD3
 *
@@ -108,13 +108,13 @@ namespace crypto
 	};
 
 	// ElGamal
-	void ElGamalEncrypt (const uint8_t * key, const uint8_t * data, uint8_t * encrypted, BN_CTX * ctx, bool zeroPadding = false);
-	bool ElGamalDecrypt (const uint8_t * key, const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx, bool zeroPadding = false);
+	void ElGamalEncrypt (const uint8_t * key, const uint8_t * data, uint8_t * encrypted, BN_CTX * ctx, bool zeroPadding = false); // 222 bytes data, 514 bytes encrypted with zeropadding, 512 without
+	bool ElGamalDecrypt (const uint8_t * key, const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx); // 514 bytes encrypted, 222 data
 	void GenerateElGamalKeyPair (uint8_t * priv, uint8_t * pub);
 
 	// ECIES
 	void ECIESEncrypt (const EC_GROUP * curve, const EC_POINT * key, const uint8_t * data, uint8_t * encrypted, BN_CTX * ctx, bool zeroPadding = false); // 222 bytes data, 514 bytes encrypted with zeropadding, 512 without
-	bool ECIESDecrypt (const EC_GROUP * curve, const BIGNUM * key, const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx, bool zeroPadding = false);
+	bool ECIESDecrypt (const EC_GROUP * curve, const BIGNUM * key, const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx); // 514 bytes encrypted, 222 data
 	void GenerateECIESKeyPair (const EC_GROUP * curve, BIGNUM *& priv, EC_POINT *& pub);
 
 	// HMAC

libi2pd/CryptoKey.cpp

@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2013-2020, The PurpleI2P Project
+* Copyright (c) 2013-2021, The PurpleI2P Project
 *
 * This file is part of Purple i2pd project and licensed under BSD3
 *
@@ -31,10 +31,10 @@ namespace crypto
 		memcpy (m_PrivateKey, priv, 256);
 	}
 
-	bool ElGamalDecryptor::Decrypt (const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx, bool zeroPadding)
+	bool ElGamalDecryptor::Decrypt (const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx)
 	{
 		if (!ctx) return false;
-		return ElGamalDecrypt (m_PrivateKey, encrypted, data, ctx, zeroPadding);
+		return ElGamalDecrypt (m_PrivateKey, encrypted, data, ctx);
 	}
 
 	ECIESP256Encryptor::ECIESP256Encryptor (const uint8_t * pub)
@@ -72,10 +72,10 @@ namespace crypto
 		if (m_PrivateKey) BN_free (m_PrivateKey);
 	}
 
-	bool ECIESP256Decryptor::Decrypt (const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx, bool zeroPadding)
+	bool ECIESP256Decryptor::Decrypt (const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx)
 	{
 		if (m_Curve && m_PrivateKey)
-			return ECIESDecrypt (m_Curve, m_PrivateKey, encrypted, data, ctx, zeroPadding);
+			return ECIESDecrypt (m_Curve, m_PrivateKey, encrypted, data, ctx);
 		return false;
 	}
 
@@ -130,10 +130,10 @@ namespace crypto
 		if (m_PrivateKey) BN_free (m_PrivateKey);
 	}
 
-	bool ECIESGOSTR3410Decryptor::Decrypt (const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx, bool zeroPadding)
+	bool ECIESGOSTR3410Decryptor::Decrypt (const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx)
 	{
 		if (m_PrivateKey)
-			return ECIESDecrypt (GetGOSTR3410Curve (eGOSTR3410CryptoProA)->GetGroup (), m_PrivateKey, encrypted, data, ctx, zeroPadding);
+			return ECIESDecrypt (GetGOSTR3410Curve (eGOSTR3410CryptoProA)->GetGroup (), m_PrivateKey, encrypted, data, ctx);
 		return false;
 	}
 
@@ -171,7 +171,7 @@ namespace crypto
 		m_StaticKeys.SetPrivateKey (priv, calculatePublic);
 	}
 
-	bool ECIESX25519AEADRatchetDecryptor::Decrypt (const uint8_t * epub, uint8_t * sharedSecret, BN_CTX * ctx, bool zeroPadding)
+	bool ECIESX25519AEADRatchetDecryptor::Decrypt (const uint8_t * epub, uint8_t * sharedSecret, BN_CTX * ctx)
 	{
 		return m_StaticKeys.Agree (epub, sharedSecret);
 	}

libi2pd/CryptoKey.h

@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2013-2020, The PurpleI2P Project
+* Copyright (c) 2013-2021, The PurpleI2P Project
 *
 * This file is part of Purple i2pd project and licensed under BSD3
 *
@@ -21,7 +21,7 @@ namespace crypto
 		public:
 
 			virtual ~CryptoKeyEncryptor () {};
-			virtual void Encrypt (const uint8_t * data, uint8_t * encrypted, BN_CTX * ctx, bool zeroPadding) = 0; // 222 bytes data, 512/514 bytes encrypted
+			virtual void Encrypt (const uint8_t * data, uint8_t * encrypted, BN_CTX * ctx, bool zeroPadding) = 0;
 	};
 
 	class CryptoKeyDecryptor
@@ -29,7 +29,7 @@ namespace crypto
 		public:
 
 			virtual ~CryptoKeyDecryptor () {};
-			virtual bool Decrypt (const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx, bool zeroPadding) = 0; // 512/514 bytes encrypted, 222 bytes data
+			virtual bool Decrypt (const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx) = 0; 
 			virtual size_t GetPublicKeyLen () const = 0; // we need it to set key in LS2
 	};
 
@@ -39,7 +39,7 @@ namespace crypto
 		public:
 
 			ElGamalEncryptor (const uint8_t * pub);
-			void Encrypt (const uint8_t * data, uint8_t * encrypted, BN_CTX * ctx, bool zeroPadding);
+			void Encrypt (const uint8_t * data, uint8_t * encrypted, BN_CTX * ctx, bool zeroPadding) override; // 222 bytes data, 512/514 bytes encrypted
 
 		private:
 
@@ -51,8 +51,8 @@ namespace crypto
 		public:
 
 			ElGamalDecryptor (const uint8_t * priv);
-			bool Decrypt (const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx, bool zeroPadding);
-			size_t GetPublicKeyLen () const { return 256; };
+			bool Decrypt (const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx) override; // 514 bytes encrypted, 222 bytes data
+			size_t GetPublicKeyLen () const override { return 256; };
 
 		private:
 
@@ -67,7 +67,7 @@ namespace crypto
 
 			ECIESP256Encryptor (const uint8_t * pub);
 			~ECIESP256Encryptor ();
-			void Encrypt (const uint8_t * data, uint8_t * encrypted, BN_CTX * ctx, bool zeroPadding);
+			void Encrypt (const uint8_t * data, uint8_t * encrypted, BN_CTX * ctx, bool zeroPadding) override;
 
 		private:
 
@@ -82,8 +82,8 @@ namespace crypto
 
 			ECIESP256Decryptor (const uint8_t * priv);
 			~ECIESP256Decryptor ();
-			bool Decrypt (const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx, bool zeroPadding);
-			size_t GetPublicKeyLen () const { return 64; };
+			bool Decrypt (const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx) override;
+			size_t GetPublicKeyLen () const override { return 64; };
 
 		private:
 
@@ -101,7 +101,7 @@ namespace crypto
 
 			ECIESGOSTR3410Encryptor (const uint8_t * pub);
 			~ECIESGOSTR3410Encryptor ();
-			void Encrypt (const uint8_t * data, uint8_t * encrypted, BN_CTX * ctx, bool zeroPadding);
+			void Encrypt (const uint8_t * data, uint8_t * encrypted, BN_CTX * ctx, bool zeroPadding) override;
 
 		private:
 
@@ -115,8 +115,8 @@ namespace crypto
 
 			ECIESGOSTR3410Decryptor (const uint8_t * priv);
 			~ECIESGOSTR3410Decryptor ();
-			bool Decrypt (const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx, bool zeroPadding);
-			size_t GetPublicKeyLen () const { return 64; };
+			bool Decrypt (const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx) override;
+			size_t GetPublicKeyLen () const override { return 64; };
 
 		private:
 
@@ -133,7 +133,7 @@ namespace crypto
 
 			ECIESX25519AEADRatchetEncryptor (const uint8_t * pub);
 			~ECIESX25519AEADRatchetEncryptor () {};
-			void Encrypt (const uint8_t *, uint8_t * pub, BN_CTX *, bool);
+			void Encrypt (const uint8_t *, uint8_t * pub, BN_CTX *, bool) override;
 			// copies m_PublicKey to pub
 
 		private:
@@ -147,9 +147,9 @@ namespace crypto
 
 			ECIESX25519AEADRatchetDecryptor (const uint8_t * priv, bool calculatePublic = false);
 			~ECIESX25519AEADRatchetDecryptor () {};
-			bool Decrypt (const uint8_t * epub, uint8_t * sharedSecret, BN_CTX * ctx, bool zeroPadding);
+			bool Decrypt (const uint8_t * epub, uint8_t * sharedSecret, BN_CTX * ctx) override;
 			// agree with static and return in sharedSecret (32 bytes)
-			size_t GetPublicKeyLen () const { return 32; };
+			size_t GetPublicKeyLen () const override { return 32; };
 			const uint8_t * GetPubicKey () const { return m_StaticKeys.GetPublicKey (); };
 
 		private:

libi2pd/Destination.cpp

@@ -1249,9 +1249,9 @@ namespace client
 	{
 		if (preferredCrypto == i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD)
 			if (m_ECIESx25519EncryptionKey && m_ECIESx25519EncryptionKey->decryptor)
-				return m_ECIESx25519EncryptionKey->decryptor->Decrypt (encrypted, data, ctx, true);
+				return m_ECIESx25519EncryptionKey->decryptor->Decrypt (encrypted, data, ctx);
 		if (m_StandardEncryptionKey && m_StandardEncryptionKey->decryptor)
-			return m_StandardEncryptionKey->decryptor->Decrypt (encrypted, data, ctx, true);
+			return m_StandardEncryptionKey->decryptor->Decrypt (encrypted, data, ctx);
 		else
 			LogPrint (eLogError, "Destinations: decryptor is not set");
 		return false;

libi2pd/RouterContext.cpp

@@ -880,7 +880,7 @@ namespace i2p
 
 	bool RouterContext::Decrypt (const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx, i2p::data::CryptoKeyType preferredCrypto) const
 	{
-		return m_Decryptor ? m_Decryptor->Decrypt (encrypted, data, ctx, true) : false;
+		return m_Decryptor ? m_Decryptor->Decrypt (encrypted, data, ctx) : false;
 	}
 
 	bool RouterContext::DecryptTunnelBuildRecord (const uint8_t * encrypted, uint8_t * data)
@@ -889,11 +889,8 @@ namespace i2p
 			return DecryptECIESTunnelBuildRecord (encrypted, data, ECIES_BUILD_REQUEST_RECORD_CLEAR_TEXT_SIZE);
 		else
 		{
-			if (!m_TunnelDecryptor) return false;	
-			BN_CTX * ctx = BN_CTX_new ();
-			bool success = m_TunnelDecryptor->Decrypt (encrypted, data, ctx, false);
-			BN_CTX_free (ctx);
-			return success;
+			LogPrint (eLogError, "Router: Non-ECIES router is not longer supported");
+			return false;
 		}
 	}
 
@@ -903,7 +900,7 @@ namespace i2p
 		m_CurrentNoiseState = m_InitialNoiseState;
 		m_CurrentNoiseState.MixHash (encrypted, 32); // h = SHA256(h || sepk)
 		uint8_t sharedSecret[32];
-		if (!m_TunnelDecryptor->Decrypt (encrypted, sharedSecret, nullptr, false))
+		if (!m_TunnelDecryptor->Decrypt (encrypted, sharedSecret, nullptr))
 		{
 			LogPrint (eLogWarning, "Router: Incorrect ephemeral public key");
 			return false;
@@ -928,7 +925,7 @@ namespace i2p
 			return DecryptECIESTunnelBuildRecord (encrypted, data, SHORT_REQUEST_RECORD_CLEAR_TEXT_SIZE);
 		else
 		{
-			LogPrint (eLogWarning, "Router: Can't decrypt short request record on non-ECIES router");
+			LogPrint (eLogError, "Router: Can't decrypt short request record on non-ECIES router");
 			return false;
 		}	 
 	}	

libi2pd_client/I2CP.cpp

@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2013-2020, The PurpleI2P Project
+* Copyright (c) 2013-2021, The PurpleI2P Project
 *
 * This file is part of Purple i2pd project and licensed under BSD3
 *
@@ -55,9 +55,9 @@ namespace client
 	bool I2CPDestination::Decrypt (const uint8_t * encrypted, uint8_t * data, BN_CTX * ctx, i2p::data::CryptoKeyType preferredCrypto) const
 	{
 		if (preferredCrypto == i2p::data::CRYPTO_KEY_TYPE_ECIES_X25519_AEAD && m_ECIESx25519Decryptor)
-			return m_ECIESx25519Decryptor->Decrypt (encrypted, data, ctx, true);
+			return m_ECIESx25519Decryptor->Decrypt (encrypted, data, ctx);
 		if (m_Decryptor)
-			return m_Decryptor->Decrypt (encrypted, data, ctx, true);
+			return m_Decryptor->Decrypt (encrypted, data, ctx);
 		else
 			LogPrint (eLogError, "I2CP: decryptor is not set");
 		return false;