From 1738d118f70a9a34b8f2e7e619534b7ce00f8d68 Mon Sep 17 00:00:00 2001
From: orignal <i2porignal@yandex.ru>
Date: Fri, 28 Oct 2022 14:06:45 -0400
Subject: [PATCH] recconnect to proxy

---
 libi2pd/SSU2.cpp | 29 ++++++++++++++++++++++++++++-
 libi2pd/SSU2.h   |  7 +++++--
 2 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/libi2pd/SSU2.cpp b/libi2pd/SSU2.cpp
index 90139c10..ee6fe53c 100644
--- a/libi2pd/SSU2.cpp
+++ b/libi2pd/SSU2.cpp
@@ -1157,6 +1157,7 @@ namespace transport
 				{
 					LogPrint (eLogError, "SSU2: Can't connect to proxy ", *m_ProxyEndpoint, " ", ecode.message ());
 					m_UDPAssociateSocket.reset (nullptr);
+					ReconnectToProxy ();
 				}
 				else
 					HandshakeWithProxy ();
@@ -1177,6 +1178,7 @@ namespace transport
 				{
 					LogPrint(eLogError, "SSU2: Proxy write error ", ecode.message());
 					m_UDPAssociateSocket.reset (nullptr);	
+					ReconnectToProxy ();
 				}	
 				else
 					ReadHandshakeWithProxyReply ();
@@ -1194,6 +1196,7 @@ namespace transport
 				{
 					LogPrint(eLogError, "SSU2: Proxy read error ", ecode.message());
 					m_UDPAssociateSocket.reset (nullptr);
+					ReconnectToProxy ();
 				}	
 				else
 				{
@@ -1224,6 +1227,7 @@ namespace transport
 				{
 					LogPrint(eLogError, "SSU2: Proxy write error ", ecode.message());
 					m_UDPAssociateSocket.reset (nullptr);	
+					ReconnectToProxy ();
 				}	
 				else
 					ReadUDPAssociateReply ();
@@ -1241,6 +1245,7 @@ namespace transport
 				{
 					LogPrint(eLogError, "SSU2: Proxy read error ", ecode.message());
 					m_UDPAssociateSocket.reset (nullptr);
+					ReconnectToProxy ();
 				}	
 				else
 				{
@@ -1280,14 +1285,36 @@ namespace transport
 				(void) bytes_transferred;
 				if (ecode)
 				{
-					LogPrint(eLogError, "SSU2: Proxy UDP Associate socket error ", ecode.message());
+					LogPrint(eLogWarning, "SSU2: Proxy UDP Associate socket error ", ecode.message());
 					m_UDPAssociateSocket.reset (nullptr);
+					m_ProxyRelayEndpoint.reset (nullptr);
+					ConnectToProxy (); // try to reconnect immediately
 				}	
 				else
 					ReadUDPAssociateSocket ();
 			});	
 	}	
 
+	void SSU2Server::ReconnectToProxy ()
+	{
+		LogPrint(eLogInfo, "SSU2: Reconnect to proxy after ", SSU2_PROXY_CONNECT_RETRY_TIMEOUT, " seconds");
+		if (m_ProxyConnectRetryTimer)
+			m_ProxyConnectRetryTimer->cancel ();
+		else	
+			m_ProxyConnectRetryTimer.reset (new boost::asio::deadline_timer (m_ReceiveService.GetService ()));
+		m_ProxyConnectRetryTimer->expires_from_now (boost::posix_time::seconds (SSU2_PROXY_CONNECT_RETRY_TIMEOUT));
+		m_ProxyConnectRetryTimer->async_wait (
+			[this](const boost::system::error_code& ecode)
+			{
+				if (ecode != boost::asio::error::operation_aborted)
+				{
+					m_UDPAssociateSocket.reset (nullptr);
+					m_ProxyRelayEndpoint.reset (nullptr);
+					ConnectToProxy ();
+				}
+			});	                                                               
+	}	
+		
 	bool SSU2Server::SetProxy (const std::string& address, uint16_t port)
 	{
 		boost::system::error_code ecode;
diff --git a/libi2pd/SSU2.h b/libi2pd/SSU2.h
index fb2925cb..c5c2c140 100644
--- a/libi2pd/SSU2.h
+++ b/libi2pd/SSU2.h
@@ -27,8 +27,9 @@ namespace transport
 	const size_t SSU2_MAX_NUM_INTRODUCERS = 3;
 	const int SSU2_TO_INTRODUCER_SESSION_DURATION = 3600; // 1 hour
 	const int SSU2_TO_INTRODUCER_SESSION_EXPIRATION = 4800; // 80 minutes
-	const int SSU2_KEEP_ALIVE_INTERVAL = 30; // 30 seconds
-
+	const int SSU2_KEEP_ALIVE_INTERVAL = 30; // in seconds
+	const int SSU2_PROXY_CONNECT_RETRY_TIMEOUT = 30; // in seconds
+	
 	class SSU2Server: private i2p::util::RunnableServiceWithWork
 	{
 		struct Packet
@@ -124,6 +125,7 @@ namespace transport
 				const uint8_t * payload, size_t payloadLen, const boost::asio::ip::udp::endpoint& to);
 			void ProcessNextPacketFromProxy (uint8_t * buf, size_t len);
 			void ConnectToProxy ();
+			void ReconnectToProxy ();
 			void HandshakeWithProxy ();
 			void ReadHandshakeWithProxyReply ();
 			void SendUDPAssociateRequest ();
@@ -155,6 +157,7 @@ namespace transport
 			std::unique_ptr<boost::asio::ip::tcp::endpoint> m_ProxyEndpoint;
 			std::unique_ptr<boost::asio::ip::tcp::socket> m_UDPAssociateSocket;
 			std::unique_ptr<boost::asio::ip::udp::endpoint> m_ProxyRelayEndpoint;
+			std::unique_ptr<boost::asio::deadline_timer> m_ProxyConnectRetryTimer;
 		
 		public: