From d3bc9eb11022002fc0c3a7ee56cd6d8f3795e9fb Mon Sep 17 00:00:00 2001
From: orignal <i2porignal@yandex.ru>
Date: Mon, 27 Jun 2022 23:03:27 -0400
Subject: [PATCH] update token and conn id after HolePunch

---
 libi2pd/SSU2.cpp        | 24 ++++++++++++++++++++++--
 libi2pd/SSU2.h          |  1 +
 libi2pd/SSU2Session.cpp | 20 ++++++++++++--------
 3 files changed, 35 insertions(+), 10 deletions(-)

diff --git a/libi2pd/SSU2.cpp b/libi2pd/SSU2.cpp
index 5b0a55dd..4210afc0 100644
--- a/libi2pd/SSU2.cpp
+++ b/libi2pd/SSU2.cpp
@@ -243,6 +243,17 @@ namespace transport
 		}
 	}
 
+	void SSU2Server::UpdateSessionConnID (uint64_t oldConnID)
+	{
+		auto it = m_Sessions.find (oldConnID);
+		if (it != m_Sessions.end ())
+		{
+			auto session = it->second;
+			m_Sessions.erase (it);
+			m_Sessions.emplace (session->GetConnID (), session);
+		}	
+	}	
+		
 	void SSU2Server::AddSessionByRouterHash (std::shared_ptr<SSU2Session> session)
 	{
 		if (session)
@@ -369,8 +380,17 @@ namespace transport
 					m_LastSession->ProcessSessionConfirmed (buf, len);
 				break;
 				case eSSU2SessionStateIntroduced:
-					m_LastSession->SetRemoteEndpoint (senderEndpoint);
-					m_LastSession->ProcessHolePunch (buf, len);
+					if (m_LastSession->GetRemoteEndpoint ().address ().is_unspecified ())	
+						m_LastSession->SetRemoteEndpoint (senderEndpoint);
+					if (m_LastSession->GetRemoteEndpoint () == senderEndpoint)
+						m_LastSession->ProcessHolePunch (buf, len);
+					else
+					{
+						LogPrint (eLogWarning, "SSU2: HolePunch endpoint ", senderEndpoint,
+							" doesn't match RelayResponse ", m_LastSession->GetRemoteEndpoint ());
+						m_LastSession->Terminate ();
+						m_LastSession = nullptr;	
+					}		
 				break;
 				case eSSU2SessionStatePeerTest:
 					m_LastSession->SetRemoteEndpoint (senderEndpoint);
diff --git a/libi2pd/SSU2.h b/libi2pd/SSU2.h
index 429cfdb7..2373ec17 100644
--- a/libi2pd/SSU2.h
+++ b/libi2pd/SSU2.h
@@ -53,6 +53,7 @@ namespace transport
 		
 			void AddSession (std::shared_ptr<SSU2Session> session);
 			void RemoveSession (uint64_t connID);
+			void UpdateSessionConnID (uint64_t oldConnID); // session has new connID
 			void AddSessionByRouterHash (std::shared_ptr<SSU2Session> session);
 			bool AddPendingOutgoingSession (std::shared_ptr<SSU2Session> session);
 			void RemovePendingOutgoingSession (const boost::asio::ip::udp::endpoint& ep);
diff --git a/libi2pd/SSU2Session.cpp b/libi2pd/SSU2Session.cpp
index 7ceb7188..e681e993 100644
--- a/libi2pd/SSU2Session.cpp
+++ b/libi2pd/SSU2Session.cpp
@@ -955,8 +955,16 @@ namespace transport
 		// connect to Charlie
 		if (m_State == eSSU2SessionStateIntroduced)
 		{
+			// create new connID
+			uint64_t oldConnID = GetConnID ();
+			RAND_bytes ((uint8_t *)&m_DestConnID, 8);
+			RAND_bytes ((uint8_t *)&m_SourceConnID, 8);	
+			m_Server.UpdateSessionConnID (oldConnID);
+			// new token
+			m_Server.UpdateOutgoingToken (m_RemoteEndpoint, headerX[1], i2p::util::GetSecondsSinceEpoch () + SSU2_TOKEN_EXPIRATION_TIMEOUT);
+			// connect
 			m_State = eSSU2SessionStateUnknown;
-			Connect ();
+			SendSessionRequest (headerX[1]);
 		}
 
 		return true;
@@ -1463,13 +1471,9 @@ namespace transport
 					s.Insert (buf + 2, 10 + csz); // nonce, timestamp, ver, csz and Charlie's endpoint
 					if (s.Verify (it->second.first->GetRemoteIdentity (), buf + 12 + csz))
 					{
-						// update Charlie's endpoint and connect
-						if (it->second.first->m_State == eSSU2SessionStateIntroduced &&
-							ExtractEndpoint (buf + 12, csz, it->second.first->m_RemoteEndpoint))
-						{
-							it->second.first->m_State = eSSU2SessionStateUnknown;
-							it->second.first->Connect ();
-						}
+						if (it->second.first->m_State == eSSU2SessionStateIntroduced) // HolePunch not received yet
+							// update Charlie's endpoint
+							ExtractEndpoint (buf + 12, csz, it->second.first->m_RemoteEndpoint);
 					}
 					else
 					{