diff --git a/src/i2p.cpp b/src/i2p.cpp index 84189452759..a3bfc23a65d 100644 --- a/src/i2p.cpp +++ b/src/i2p.cpp @@ -380,7 +380,9 @@ void Session::CreateIfNotCreatedAlready() // in the reply in DESTINATION=. const Reply& reply = SendRequestAndGetReply( *sock, - strprintf("SESSION CREATE STYLE=STREAM ID=%s DESTINATION=TRANSIENT SIGNATURE_TYPE=7", session_id)); + strprintf("SESSION CREATE STYLE=STREAM ID=%s DESTINATION=TRANSIENT SIGNATURE_TYPE=7 " + "inbound.quantity=1 outbound.quantity=1", + session_id)); m_private_key = DecodeI2PBase64(reply.Get("DESTINATION")); } else { @@ -396,7 +398,8 @@ void Session::CreateIfNotCreatedAlready() const std::string& private_key_b64 = SwapBase64(EncodeBase64(m_private_key)); SendRequestAndGetReply(*sock, - strprintf("SESSION CREATE STYLE=STREAM ID=%s DESTINATION=%s", + strprintf("SESSION CREATE STYLE=STREAM ID=%s DESTINATION=%s " + "inbound.quantity=3 outbound.quantity=3", session_id, private_key_b64)); } diff --git a/src/net.cpp b/src/net.cpp index 15ed6688341..4e4f2f78be7 100644 --- a/src/net.cpp +++ b/src/net.cpp @@ -436,6 +436,7 @@ static CAddress GetBindAddress(const Sock& sock) CNode* CConnman::ConnectNode(CAddress addrConnect, const char *pszDest, bool fCountFailure, ConnectionType conn_type) { + AssertLockNotHeld(m_unused_i2p_sessions_mutex); assert(conn_type != ConnectionType::INBOUND); if (pszDest == nullptr) { @@ -496,8 +497,23 @@ CNode* CConnman::ConnectNode(CAddress addrConnect, const char *pszDest, bool fCo if (m_i2p_sam_session) { connected = m_i2p_sam_session->Connect(addrConnect, conn, proxyConnectionFailed); } else { - i2p_transient_session = std::make_unique(proxy.proxy, &interruptNet); + { + LOCK(m_unused_i2p_sessions_mutex); + if (m_unused_i2p_sessions.empty()) { + i2p_transient_session = + std::make_unique(proxy.proxy, &interruptNet); + } else { + i2p_transient_session.swap(m_unused_i2p_sessions.front()); + m_unused_i2p_sessions.pop(); + } + } connected = i2p_transient_session->Connect(addrConnect, conn, proxyConnectionFailed); + if (!connected) { + LOCK(m_unused_i2p_sessions_mutex); + if (m_unused_i2p_sessions.size() < MAX_UNUSED_I2P_SESSIONS_SIZE) { + m_unused_i2p_sessions.emplace(i2p_transient_session.release()); + } + } } if (connected) { @@ -1053,6 +1069,7 @@ void CConnman::CreateNodeFromAcceptedSocket(std::unique_ptr&& sock, bool CConnman::AddConnection(const std::string& address, ConnectionType conn_type) { + AssertLockNotHeld(m_unused_i2p_sessions_mutex); std::optional max_connections; switch (conn_type) { case ConnectionType::INBOUND: @@ -1517,6 +1534,7 @@ void CConnman::DumpAddresses() void CConnman::ProcessAddrFetch() { + AssertLockNotHeld(m_unused_i2p_sessions_mutex); std::string strDest; { LOCK(m_addr_fetches_mutex); @@ -1598,6 +1616,7 @@ std::unordered_set CConnman::GetReachableEmptyNetworks() const void CConnman::ThreadOpenConnections(const std::vector connect) { + AssertLockNotHeld(m_unused_i2p_sessions_mutex); SetSyscallSandboxPolicy(SyscallSandboxPolicy::NET_OPEN_CONNECTION); FastRandomContext rng; // Connect to specific addresses @@ -1947,6 +1966,7 @@ std::vector CConnman::GetAddedNodeInfo() const void CConnman::ThreadOpenAddedConnections() { + AssertLockNotHeld(m_unused_i2p_sessions_mutex); SetSyscallSandboxPolicy(SyscallSandboxPolicy::NET_ADD_CONNECTION); while (true) { @@ -1976,6 +1996,7 @@ void CConnman::ThreadOpenAddedConnections() // if successful, this moves the passed grant to the constructed node void CConnman::OpenNetworkConnection(const CAddress& addrConnect, bool fCountFailure, CSemaphoreGrant *grantOutbound, const char *pszDest, ConnectionType conn_type) { + AssertLockNotHeld(m_unused_i2p_sessions_mutex); assert(conn_type != ConnectionType::INBOUND); // diff --git a/src/net.h b/src/net.h index 666e0f3b8a5..2025dfdb054 100644 --- a/src/net.h +++ b/src/net.h @@ -38,6 +38,7 @@ #include #include #include +#include #include #include #include @@ -744,7 +745,7 @@ public: bool GetNetworkActive() const { return fNetworkActive; }; bool GetUseAddrmanOutgoing() const { return m_use_addrman_outgoing; }; void SetNetworkActive(bool active); - void OpenNetworkConnection(const CAddress& addrConnect, bool fCountFailure, CSemaphoreGrant* grantOutbound, const char* strDest, ConnectionType conn_type); + void OpenNetworkConnection(const CAddress& addrConnect, bool fCountFailure, CSemaphoreGrant* grantOutbound, const char* strDest, ConnectionType conn_type) EXCLUSIVE_LOCKS_REQUIRED(!m_unused_i2p_sessions_mutex); bool CheckIncomingNonce(uint64_t nonce); bool ForNode(NodeId id, std::function func); @@ -820,7 +821,7 @@ public: * - Max total outbound connection capacity filled * - Max connection capacity for type is filled */ - bool AddConnection(const std::string& address, ConnectionType conn_type); + bool AddConnection(const std::string& address, ConnectionType conn_type) EXCLUSIVE_LOCKS_REQUIRED(!m_unused_i2p_sessions_mutex); size_t GetNodeCount(ConnectionDirection) const; void GetNodeStats(std::vector& vstats) const; @@ -886,10 +887,10 @@ private: bool Bind(const CService& addr, unsigned int flags, NetPermissionFlags permissions); bool InitBinds(const Options& options); - void ThreadOpenAddedConnections() EXCLUSIVE_LOCKS_REQUIRED(!m_added_nodes_mutex); + void ThreadOpenAddedConnections() EXCLUSIVE_LOCKS_REQUIRED(!m_added_nodes_mutex, !m_unused_i2p_sessions_mutex); void AddAddrFetch(const std::string& strDest) EXCLUSIVE_LOCKS_REQUIRED(!m_addr_fetches_mutex); - void ProcessAddrFetch() EXCLUSIVE_LOCKS_REQUIRED(!m_addr_fetches_mutex); - void ThreadOpenConnections(std::vector connect) EXCLUSIVE_LOCKS_REQUIRED(!m_addr_fetches_mutex, !m_added_nodes_mutex, !m_nodes_mutex); + void ProcessAddrFetch() EXCLUSIVE_LOCKS_REQUIRED(!m_addr_fetches_mutex, !m_unused_i2p_sessions_mutex); + void ThreadOpenConnections(std::vector connect) EXCLUSIVE_LOCKS_REQUIRED(!m_addr_fetches_mutex, !m_added_nodes_mutex, !m_nodes_mutex, !m_unused_i2p_sessions_mutex); void ThreadMessageHandler() EXCLUSIVE_LOCKS_REQUIRED(!mutexMsgProc); void ThreadI2PAcceptIncoming(); void AcceptConnection(const ListenSocket& hListenSocket); @@ -956,7 +957,7 @@ private: bool AlreadyConnectedToAddress(const CAddress& addr); bool AttemptToEvictConnection(); - CNode* ConnectNode(CAddress addrConnect, const char *pszDest, bool fCountFailure, ConnectionType conn_type); + CNode* ConnectNode(CAddress addrConnect, const char *pszDest, bool fCountFailure, ConnectionType conn_type) EXCLUSIVE_LOCKS_REQUIRED(!m_unused_i2p_sessions_mutex); void AddWhitelistPermissionFlags(NetPermissionFlags& flags, const CNetAddr &addr) const; void DeleteNode(CNode* pnode); @@ -1133,6 +1134,26 @@ private: */ std::vector m_onion_binds; + /** + * Mutex protecting m_i2p_sam_sessions. + */ + Mutex m_unused_i2p_sessions_mutex; + + /** + * A pool of created I2P SAM transient sessions that should be used instead + * of creating new ones in order to reduce the load on the I2P network. + * Creating a session in I2P is not cheap, thus if this is not empty, then + * pick an entry from it instead of creating a new session. If connecting to + * a host fails, then the created session is put to this pool for reuse. + */ + std::queue> m_unused_i2p_sessions GUARDED_BY(m_unused_i2p_sessions_mutex); + + /** + * Cap on the size of `m_unused_i2p_sessions`, to ensure it does not + * unexpectedly use too much memory. + */ + static constexpr size_t MAX_UNUSED_I2P_SESSIONS_SIZE{10}; + /** * RAII helper to atomically create a copy of `m_nodes` and add a reference * to each of the nodes. The nodes are released when this object is destroyed.