don't adjust clock if offsets came from same router

PurpleI2P · Jan 25, 2024 · 70639f1 · 70639f1
1 parent c5a1806
commit 70639f1
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Showing 3 changed files with 26 additions and 12 deletions.
diff --git a/libi2pd/SSU2.cpp b/libi2pd/SSU2.cpp
@@ -210,27 +210,40 @@ namespace transport
 		return ep.port ();
 	}
 
-	void SSU2Server::AdjustTimeOffset (int64_t offset)
+	void SSU2Server::AdjustTimeOffset (int64_t offset, std::shared_ptr<const i2p::data::IdentityEx> from)
 	{
 		if (offset)
 		{	
 			if (m_PendingTimeOffset) // one more
 			{	
-				if (std::abs (m_PendingTimeOffset - offset) < SSU2_CLOCK_SKEW)
+				if (m_PendingTimeOffsetFrom && from && 
+					m_PendingTimeOffsetFrom->GetIdentHash ().GetLL()[0] != from->GetIdentHash ().GetLL()[0]) // from different routers
 				{	
-					offset = (m_PendingTimeOffset + offset)/2; // average
-					LogPrint (eLogWarning, "SSU2: Clock adjusted by ", offset, " seconds");
-					i2p::util::AdjustTimeOffset (offset);
-				}	
+					if (std::abs (m_PendingTimeOffset - offset) < SSU2_CLOCK_SKEW)
+					{	
+						offset = (m_PendingTimeOffset + offset)/2; // average
+						LogPrint (eLogWarning, "SSU2: Clock adjusted by ", offset, " seconds");
+						i2p::util::AdjustTimeOffset (offset);
+					}	
+					else
+						LogPrint (eLogWarning, "SSU2: Time offsets are too different. Clock not adjusted");
+					m_PendingTimeOffset = 0;
+					m_PendingTimeOffsetFrom = nullptr;
+				}
 				else
-					LogPrint (eLogWarning, "SSU2: Time offsets are too different. Clock not adjusted");
-				m_PendingTimeOffset = 0;
+					LogPrint (eLogWarning, "SSU2: Time offsets from same router. Clock not adjusted");
 			}
 			else
+			{	
 				m_PendingTimeOffset = offset; // first 
+				m_PendingTimeOffsetFrom = from;
+			}	
 		}	
 		else
+		{	
 			m_PendingTimeOffset = 0; // reset
+			m_PendingTimeOffsetFrom = nullptr;
+		}	
 	}	
 
 	boost::asio::ip::udp::socket& SSU2Server::OpenSocket (const boost::asio::ip::udp::endpoint& localEndpoint)

diff --git a/libi2pd/SSU2.h b/libi2pd/SSU2.h
@@ -67,7 +67,7 @@ namespace transport
 			bool IsSupported (const boost::asio::ip::address& addr) const;
 			uint16_t GetPort (bool v4) const;
 			bool IsSyncClockFromPeers () const { return m_IsSyncClockFromPeers; };
-			void AdjustTimeOffset (int64_t offset);
+			void AdjustTimeOffset (int64_t offset, std::shared_ptr<const i2p::data::IdentityEx> from);
 
 			void AddSession (std::shared_ptr<SSU2Session> session);
 			void RemoveSession (uint64_t connID);
@@ -164,6 +164,7 @@ namespace transport
 			bool m_IsPublished; // if we maintain introducers
 			bool m_IsSyncClockFromPeers;
 			int64_t m_PendingTimeOffset; // during peer test
+			std::shared_ptr<const i2p::data::IdentityEx> m_PendingTimeOffsetFrom;
 
 			// proxy
 			bool m_IsThroughProxy;

diff --git a/libi2pd/SSU2Session.cpp b/libi2pd/SSU2Session.cpp
@@ -1671,10 +1671,10 @@ namespace transport
 						if (std::abs (offset) > SSU2_CLOCK_THRESHOLD)
 						{	
 							LogPrint (eLogWarning, "SSU2: Time offset ", offset, " from ", m_RemoteEndpoint);
-							m_Server.AdjustTimeOffset (-offset);
+							m_Server.AdjustTimeOffset (-offset, GetRemoteIdentity ());
 						}	
 						else
-							m_Server.AdjustTimeOffset (0);
+							m_Server.AdjustTimeOffset (0, nullptr);
 					}
 					else if (std::abs (offset) > SSU2_CLOCK_SKEW)
 					{
@@ -2485,7 +2485,7 @@ namespace transport
 				i2p::context.SetTestingV6 (testing);
 		}
 		if (!testing)
-			m_Server.AdjustTimeOffset (0); // reset time offset when testing is over
+			m_Server.AdjustTimeOffset (0, nullptr); // reset time offset when testing is over
 	}
 
 	size_t SSU2Session::CreateAddressBlock (uint8_t * buf, size_t len, const boost::asio::ip::udp::endpoint& ep)