compressable crypto key and padding for routers and destination

libi2pd/Identity.cpp

@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2013-2020, The PurpleI2P Project
+* Copyright (c) 2013-2022, The PurpleI2P Project
 *
 * This file is part of Purple i2pd project and licensed under BSD3
 *
@@ -49,13 +49,22 @@ namespace data
 
 	IdentityEx::IdentityEx(const uint8_t * publicKey, const uint8_t * signingKey, SigningKeyType type, CryptoKeyType cryptoType)
 	{
+		uint8_t randomPaddingBlock[32];
+		RAND_bytes (randomPaddingBlock, 32);
 		if (cryptoType == CRYPTO_KEY_TYPE_ECIES_X25519_AEAD)
 		{
-			memcpy (m_StandardIdentity.publicKey, publicKey, 32);
+			memcpy (m_StandardIdentity.publicKey, publicKey ? publicKey : randomPaddingBlock, 32);
-			RAND_bytes (m_StandardIdentity.publicKey + 32, 224);
+			for (int i = 0; i < 7; i++) // 224 bytes
+				memcpy (m_StandardIdentity.publicKey + 32*i, randomPaddingBlock, 32);
 		}
 		else
-			memcpy (m_StandardIdentity.publicKey, publicKey, 256);
+		{
+			if (publicKey)
+				memcpy (m_StandardIdentity.publicKey, publicKey, 256);
+			else
+				for (int i = 0; i < 8; i++) // 256 bytes
+					memcpy (m_StandardIdentity.publicKey + 32*i, randomPaddingBlock, 32);
+		}	
 		if (type != SIGNING_KEY_TYPE_DSA_SHA1)
 		{
 			size_t excessLen = 0;
@@ -93,7 +102,8 @@ namespace data
 				case SIGNING_KEY_TYPE_REDDSA_SHA512_ED25519:
 				{
 					size_t padding = 128 - i2p::crypto::EDDSA25519_PUBLIC_KEY_LENGTH; // 96 = 128 - 32
-					RAND_bytes (m_StandardIdentity.signingKey, padding);
+					for (int i = 0; i < 3; i++) // 96 bytes
+						memcpy (m_StandardIdentity.signingKey + 32*i, randomPaddingBlock, 32);
 					memcpy (m_StandardIdentity.signingKey + padding, signingKey, i2p::crypto::EDDSA25519_PUBLIC_KEY_LENGTH);
 					break;
 				}
@@ -695,7 +705,7 @@ namespace data
 		return nullptr;
 	}
 
-	PrivateKeys PrivateKeys::CreateRandomKeys (SigningKeyType type, CryptoKeyType cryptoType)
+	PrivateKeys PrivateKeys::CreateRandomKeys (SigningKeyType type, CryptoKeyType cryptoType, bool isDestination)
 	{
 		if (type != SIGNING_KEY_TYPE_DSA_SHA1)
 		{
@@ -705,9 +715,12 @@ namespace data
 			GenerateSigningKeyPair (type, keys.m_SigningPrivateKey, signingPublicKey);
 			// encryption
 			uint8_t publicKey[256];
-			GenerateCryptoKeyPair (cryptoType, keys.m_PrivateKey, publicKey);
+			if (isDestination)
+				RAND_bytes (keys.m_PrivateKey, 256);
+			else	
+				GenerateCryptoKeyPair (cryptoType, keys.m_PrivateKey, publicKey);
 			// identity
-			keys.m_Public = std::make_shared<IdentityEx> (publicKey, signingPublicKey, type, cryptoType);
+			keys.m_Public = std::make_shared<IdentityEx> (isDestination ? nullptr : publicKey, signingPublicKey, type, cryptoType);
 
 			keys.CreateSigner ();
 			return keys;

libi2pd/Identity.h

@@ -1,5 +1,5 @@
 /*
-* Copyright (c) 2013-2021, The PurpleI2P Project
+* Copyright (c) 2013-2022, The PurpleI2P Project
 *
 * This file is part of Purple i2pd project and licensed under BSD3
 *
@@ -171,7 +171,7 @@ namespace data
 			std::shared_ptr<i2p::crypto::CryptoKeyDecryptor> CreateDecryptor (const uint8_t * key) const;
 
 			static std::shared_ptr<i2p::crypto::CryptoKeyDecryptor> CreateDecryptor (CryptoKeyType cryptoType, const uint8_t * key);
-			static PrivateKeys CreateRandomKeys (SigningKeyType type = SIGNING_KEY_TYPE_DSA_SHA1, CryptoKeyType cryptoType = CRYPTO_KEY_TYPE_ELGAMAL);
+			static PrivateKeys CreateRandomKeys (SigningKeyType type = SIGNING_KEY_TYPE_DSA_SHA1, CryptoKeyType cryptoType = CRYPTO_KEY_TYPE_ELGAMAL, bool isDestination = false);
 			static void GenerateSigningKeyPair (SigningKeyType type, uint8_t * priv, uint8_t * pub);
 			static void GenerateCryptoKeyPair (CryptoKeyType type, uint8_t * priv, uint8_t * pub); // priv and pub are 256 bytes long
 			static i2p::crypto::Signer * CreateSigner (SigningKeyType keyType, const uint8_t * priv);

libi2pd_client/BOB.cpp

@@ -547,7 +547,7 @@ namespace client
 		}
 
 
-		m_Keys = i2p::data::PrivateKeys::CreateRandomKeys (signatureType, cryptoType);
+		m_Keys = i2p::data::PrivateKeys::CreateRandomKeys (signatureType, cryptoType, true);
 		SendReplyOK (m_Keys.GetPublic ()->ToBase64 ().c_str ());
 	}
 

libi2pd_client/ClientContext.cpp

@@ -261,7 +261,7 @@ namespace client
 		static const std::string transient("transient");
 		if (!filename.compare (0, transient.length (), transient)) // starts with transient
 		{
-			keys = i2p::data::PrivateKeys::CreateRandomKeys (sigType, cryptoType);
+			keys = i2p::data::PrivateKeys::CreateRandomKeys (sigType, cryptoType, true);
 			LogPrint (eLogInfo, "Clients: New transient keys address ", m_AddressBook.ToAddress(keys.GetPublic ()->GetIdentHash ()), " created");
 			return true;
 		}
@@ -288,7 +288,7 @@ namespace client
 		else
 		{
 			LogPrint (eLogError, "Clients: Can't open file ", fullPath, " Creating new one with signature type ", sigType, " crypto type ", cryptoType);
-			keys = i2p::data::PrivateKeys::CreateRandomKeys (sigType, cryptoType);
+			keys = i2p::data::PrivateKeys::CreateRandomKeys (sigType, cryptoType, true);
 			std::ofstream f (fullPath, std::ofstream::binary | std::ofstream::out);
 			size_t len = keys.GetFullLen ();
 			uint8_t * buf = new uint8_t[len];
@@ -328,7 +328,7 @@ namespace client
 		i2p::data::SigningKeyType sigType, i2p::data::CryptoKeyType cryptoType,
 		const std::map<std::string, std::string> * params)
 	{
-		i2p::data::PrivateKeys keys = i2p::data::PrivateKeys::CreateRandomKeys (sigType, cryptoType);
+		i2p::data::PrivateKeys keys = i2p::data::PrivateKeys::CreateRandomKeys (sigType, cryptoType, true);
 		auto localDestination = std::make_shared<RunnableClientDestination> (keys, isPublic, params);
 		AddLocalDestination (localDestination);
 		return localDestination;
@@ -339,7 +339,7 @@ namespace client
 		i2p::data::SigningKeyType sigType, i2p::data::CryptoKeyType cryptoType,
 		const std::map<std::string, std::string> * params)
 	{
-		i2p::data::PrivateKeys keys = i2p::data::PrivateKeys::CreateRandomKeys (sigType, cryptoType);
+		i2p::data::PrivateKeys keys = i2p::data::PrivateKeys::CreateRandomKeys (sigType, cryptoType, true);
 		auto localDestination = std::make_shared<ClientDestination> (service, keys, isPublic, params);
 		AddLocalDestination (localDestination);
 		return localDestination;

libi2pd_client/SAM.cpp

@@ -709,7 +709,7 @@ namespace client
 				LogPrint (eLogWarning, "SAM: ", SAM_PARAM_CRYPTO_TYPE, "error: ", ex.what ());
 			}
 		}
-		auto keys = i2p::data::PrivateKeys::CreateRandomKeys (signatureType, cryptoType);
+		auto keys = i2p::data::PrivateKeys::CreateRandomKeys (signatureType, cryptoType, true);
 #ifdef _MSC_VER
 		size_t l = sprintf_s (m_Buffer, SAM_SOCKET_BUFFER_SIZE, SAM_DEST_REPLY,
 			keys.GetPublic ()->ToBase64 ().c_str (), keys.ToBase64 ().c_str ());