From acc5592f590248067e41cdbed383eb337f3ebe6b Mon Sep 17 00:00:00 2001
From: orignal <i2porignal@yandex.ru>
Date: Tue, 13 Oct 2020 21:12:52 -0400
Subject: [PATCH] create DH keys for SSU session directly

---
 libi2pd/SSUSession.cpp     | 12 ++++++++----
 libi2pd/SSUSession.h       |  1 +
 libi2pd/TransportSession.h |  3 +--
 libi2pd/Transports.cpp     | 14 +-------------
 libi2pd/Transports.h       |  4 ----
 5 files changed, 11 insertions(+), 23 deletions(-)

diff --git a/libi2pd/SSUSession.cpp b/libi2pd/SSUSession.cpp
index 399b2fc7..9ce6e2e3 100644
--- a/libi2pd/SSUSession.cpp
+++ b/libi2pd/SSUSession.cpp
@@ -224,7 +224,11 @@ namespace transport
 			return;
 		}
 		if (!m_DHKeysPair)
-			m_DHKeysPair = transports.GetNextDHKeysPair ();
+		{
+			auto pair = std::make_shared<i2p::crypto::DHKeys> ();
+			pair->GenerateKeys ();
+			m_DHKeysPair = pair;
+		}	
 		CreateAESandMacKey (buf + headerSize);
 		SendSessionCreated (buf + headerSize, sendRelayTag);
 	}
@@ -826,9 +830,9 @@ namespace transport
 	{
 		if (m_State == eSessionStateUnknown)
 		{
-			// set connect timer
-			ScheduleConnectTimer ();
-			m_DHKeysPair = transports.GetNextDHKeysPair ();
+			ScheduleConnectTimer (); // set connect timer
+			m_DHKeysPair = std::make_shared<i2p::crypto::DHKeys> ();
+			m_DHKeysPair->GenerateKeys ();
 			SendSessionRequest ();
 		}
 	}
diff --git a/libi2pd/SSUSession.h b/libi2pd/SSUSession.h
index ea820517..3aa04638 100644
--- a/libi2pd/SSUSession.h
+++ b/libi2pd/SSUSession.h
@@ -166,6 +166,7 @@ namespace transport
 			bool m_IsDataReceived;
 			std::unique_ptr<SignedData> m_SignedData; // we need it for SessionConfirmed only
 			std::map<uint32_t, std::shared_ptr<const i2p::data::RouterInfo> > m_RelayRequests; // nonce->Charlie
+			std::shared_ptr<i2p::crypto::DHKeys> m_DHKeysPair; // X - for client and Y - for server
 	};
 }
 }
diff --git a/libi2pd/TransportSession.h b/libi2pd/TransportSession.h
index a97f246f..12d4894b 100644
--- a/libi2pd/TransportSession.h
+++ b/libi2pd/TransportSession.h
@@ -64,7 +64,7 @@ namespace transport
 		public:
 
 			TransportSession (std::shared_ptr<const i2p::data::RouterInfo> router, int terminationTimeout):
-				m_DHKeysPair (nullptr), m_NumSentBytes (0), m_NumReceivedBytes (0), m_IsOutgoing (router), m_TerminationTimeout (terminationTimeout),
+				m_NumSentBytes (0), m_NumReceivedBytes (0), m_IsOutgoing (router), m_TerminationTimeout (terminationTimeout),
 				m_LastActivityTimestamp (i2p::util::GetSecondsSinceEpoch ())
 			{
 				if (router)
@@ -103,7 +103,6 @@ namespace transport
 
 			std::shared_ptr<const i2p::data::IdentityEx> m_RemoteIdentity;
 			mutable std::mutex m_RemoteIdentityMutex;
-			std::shared_ptr<i2p::crypto::DHKeys> m_DHKeysPair; // X - for client and Y - for server
 			size_t m_NumSentBytes, m_NumReceivedBytes;
 			bool m_IsOutgoing;
 			int m_TerminationTimeout;
diff --git a/libi2pd/Transports.cpp b/libi2pd/Transports.cpp
index 8fe4a731..4e0aa6a5 100644
--- a/libi2pd/Transports.cpp
+++ b/libi2pd/Transports.cpp
@@ -134,7 +134,7 @@ namespace transport
 		m_IsOnline (true), m_IsRunning (false), m_IsNAT (true), m_CheckReserved(true), m_Thread (nullptr),
 		m_Service (nullptr), m_Work (nullptr), m_PeerCleanupTimer (nullptr), m_PeerTestTimer (nullptr),
 		m_SSUServer (nullptr), m_NTCP2Server (nullptr),
-		m_DHKeysPairSupplier (5), m_X25519KeysPairSupplier (5), // 5 pre-generated keys
+		m_X25519KeysPairSupplier (5), // 5 pre-generated keys
 		m_TotalSentBytes(0), m_TotalReceivedBytes(0), m_TotalTransitTransmittedBytes (0),
 		m_InBandwidth (0), m_OutBandwidth (0), m_TransitBandwidth(0),
 		m_LastInBandwidthUpdateBytes (0), m_LastOutBandwidthUpdateBytes (0),
@@ -165,7 +165,6 @@ namespace transport
 		}
 
 		i2p::config::GetOption("nat", m_IsNAT);
-		m_DHKeysPairSupplier.Start ();
 		m_X25519KeysPairSupplier.Start ();
 		m_IsRunning = true;
 		m_Thread = new std::thread (std::bind (&Transports::Run, this));
@@ -260,7 +259,6 @@ namespace transport
 			m_NTCP2Server = nullptr;
 		}
 
-		m_DHKeysPairSupplier.Stop ();
 		m_X25519KeysPairSupplier.Stop ();
 		m_IsRunning = false;
 		if (m_Service) m_Service->stop ();
@@ -540,16 +538,6 @@ namespace transport
 		}
 	}
 
-	std::shared_ptr<i2p::crypto::DHKeys> Transports::GetNextDHKeysPair ()
-	{
-		return m_DHKeysPairSupplier.Acquire ();
-	}
-
-	void Transports::ReuseDHKeysPair (std::shared_ptr<i2p::crypto::DHKeys> pair)
-	{
-		m_DHKeysPairSupplier.Return (pair);
-	}
-
 	std::shared_ptr<i2p::crypto::X25519Keys> Transports::GetNextX25519KeysPair ()
 	{
 		return m_X25519KeysPairSupplier.Acquire ();
diff --git a/libi2pd/Transports.h b/libi2pd/Transports.h
index 7108fbac..d480840a 100644
--- a/libi2pd/Transports.h
+++ b/libi2pd/Transports.h
@@ -59,7 +59,6 @@ namespace transport
 			std::condition_variable m_Acquired;
 			std::mutex m_AcquiredMutex;
 	};
-	typedef EphemeralKeysSupplier<i2p::crypto::DHKeys> DHKeysPairSupplier;
 	typedef EphemeralKeysSupplier<i2p::crypto::X25519Keys> X25519KeysPairSupplier;
 	
 	struct Peer
@@ -97,8 +96,6 @@ namespace transport
 			void SetOnline (bool online);
 
 			boost::asio::io_service& GetService () { return *m_Service; };
-			std::shared_ptr<i2p::crypto::DHKeys> GetNextDHKeysPair ();
-			void ReuseDHKeysPair (std::shared_ptr<i2p::crypto::DHKeys> pair);
 			std::shared_ptr<i2p::crypto::X25519Keys> GetNextX25519KeysPair ();
 			void ReuseX25519KeysPair (std::shared_ptr<i2p::crypto::X25519Keys> pair);
 
@@ -166,7 +163,6 @@ namespace transport
 			mutable std::mutex m_PeersMutex;
 			std::unordered_map<i2p::data::IdentHash, Peer> m_Peers;
 
-			DHKeysPairSupplier m_DHKeysPairSupplier;
 			X25519KeysPairSupplier m_X25519KeysPairSupplier;
 
 			std::atomic<uint64_t> m_TotalSentBytes, m_TotalReceivedBytes, m_TotalTransitTransmittedBytes;