diff options
Diffstat (limited to 'src/net.cpp')
-rw-r--r-- | src/net.cpp | 172 |
1 files changed, 96 insertions, 76 deletions
diff --git a/src/net.cpp b/src/net.cpp index e388f05b03..4801f5c1f9 100644 --- a/src/net.cpp +++ b/src/net.cpp @@ -412,6 +412,9 @@ CNode* CConnman::ConnectNode(CAddress addrConnect, const char *pszDest, bool fCo // Resolve const uint16_t default_port{pszDest != nullptr ? GetDefaultPort(pszDest) : m_params.GetDefaultPort()}; + + // Collection of addresses to try to connect to: either all dns resolved addresses if a domain name (pszDest) is provided, or addrConnect otherwise. + std::vector<CAddress> connect_to{}; if (pszDest) { std::vector<CService> resolved{Lookup(pszDest, default_port, fNameLookup && !HaveNameProxy(), 256)}; if (!resolved.empty()) { @@ -432,8 +435,16 @@ CNode* CConnman::ConnectNode(CAddress addrConnect, const char *pszDest, bool fCo LogPrintf("Not opening a connection to %s, already connected to %s\n", pszDest, addrConnect.ToStringAddrPort()); return nullptr; } + // Add the address to the resolved addresses vector so we can try to connect to it later on + connect_to.push_back(addrConnect); } + } else { + // For resolution via proxy + connect_to.push_back(addrConnect); } + } else { + // Connect via addrConnect directly + connect_to.push_back(addrConnect); } // Connect @@ -443,94 +454,99 @@ CNode* CConnman::ConnectNode(CAddress addrConnect, const char *pszDest, bool fCo assert(!addr_bind.IsValid()); std::unique_ptr<i2p::sam::Session> i2p_transient_session; - if (addrConnect.IsValid()) { - const bool use_proxy{GetProxy(addrConnect.GetNetwork(), proxy)}; - bool proxyConnectionFailed = false; + for (auto& target_addr: connect_to) { + if (target_addr.IsValid()) { + const bool use_proxy{GetProxy(target_addr.GetNetwork(), proxy)}; + bool proxyConnectionFailed = false; - if (addrConnect.IsI2P() && use_proxy) { - i2p::Connection conn; - bool connected{false}; + if (target_addr.IsI2P() && use_proxy) { + i2p::Connection conn; + bool connected{false}; - if (m_i2p_sam_session) { - connected = m_i2p_sam_session->Connect(addrConnect, conn, proxyConnectionFailed); - } else { - { - LOCK(m_unused_i2p_sessions_mutex); - if (m_unused_i2p_sessions.empty()) { - i2p_transient_session = - std::make_unique<i2p::sam::Session>(proxy, &interruptNet); - } else { - i2p_transient_session.swap(m_unused_i2p_sessions.front()); - m_unused_i2p_sessions.pop(); + if (m_i2p_sam_session) { + connected = m_i2p_sam_session->Connect(target_addr, conn, proxyConnectionFailed); + } else { + { + LOCK(m_unused_i2p_sessions_mutex); + if (m_unused_i2p_sessions.empty()) { + i2p_transient_session = + std::make_unique<i2p::sam::Session>(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()); + connected = i2p_transient_session->Connect(target_addr, 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) { - sock = std::move(conn.sock); - addr_bind = CAddress{conn.me, NODE_NONE}; + if (connected) { + sock = std::move(conn.sock); + addr_bind = CAddress{conn.me, NODE_NONE}; + } + } else if (use_proxy) { + LogPrintLevel(BCLog::PROXY, BCLog::Level::Debug, "Using proxy: %s to connect to %s\n", proxy.ToString(), target_addr.ToStringAddrPort()); + sock = ConnectThroughProxy(proxy, target_addr.ToStringAddr(), target_addr.GetPort(), proxyConnectionFailed); + } else { + // no proxy needed (none set for target network) + sock = ConnectDirectly(target_addr, conn_type == ConnectionType::MANUAL); } - } else if (use_proxy) { - LogPrintLevel(BCLog::PROXY, BCLog::Level::Debug, "Using proxy: %s to connect to %s:%s\n", proxy.ToString(), addrConnect.ToStringAddr(), addrConnect.GetPort()); - sock = ConnectThroughProxy(proxy, addrConnect.ToStringAddr(), addrConnect.GetPort(), proxyConnectionFailed); - } else { - // no proxy needed (none set for target network) - sock = ConnectDirectly(addrConnect, conn_type == ConnectionType::MANUAL); + if (!proxyConnectionFailed) { + // If a connection to the node was attempted, and failure (if any) is not caused by a problem connecting to + // the proxy, mark this as an attempt. + addrman.Attempt(target_addr, fCountFailure); + } + } else if (pszDest && GetNameProxy(proxy)) { + std::string host; + uint16_t port{default_port}; + SplitHostPort(std::string(pszDest), port, host); + bool proxyConnectionFailed; + sock = ConnectThroughProxy(proxy, host, port, proxyConnectionFailed); + } + // Check any other resolved address (if any) if we fail to connect + if (!sock) { + continue; } - if (!proxyConnectionFailed) { - // If a connection to the node was attempted, and failure (if any) is not caused by a problem connecting to - // the proxy, mark this as an attempt. - addrman.Attempt(addrConnect, fCountFailure); + + NetPermissionFlags permission_flags = NetPermissionFlags::None; + std::vector<NetWhitelistPermissions> whitelist_permissions = conn_type == ConnectionType::MANUAL ? vWhitelistedRangeOutgoing : std::vector<NetWhitelistPermissions>{}; + AddWhitelistPermissionFlags(permission_flags, target_addr, whitelist_permissions); + + // Add node + NodeId id = GetNewNodeId(); + uint64_t nonce = GetDeterministicRandomizer(RANDOMIZER_ID_LOCALHOSTNONCE).Write(id).Finalize(); + if (!addr_bind.IsValid()) { + addr_bind = GetBindAddress(*sock); } - } else if (pszDest && GetNameProxy(proxy)) { - std::string host; - uint16_t port{default_port}; - SplitHostPort(std::string(pszDest), port, host); - bool proxyConnectionFailed; - sock = ConnectThroughProxy(proxy, host, port, proxyConnectionFailed); - } - if (!sock) { - return nullptr; - } + CNode* pnode = new CNode(id, + std::move(sock), + target_addr, + CalculateKeyedNetGroup(target_addr), + nonce, + addr_bind, + pszDest ? pszDest : "", + conn_type, + /*inbound_onion=*/false, + CNodeOptions{ + .permission_flags = permission_flags, + .i2p_sam_session = std::move(i2p_transient_session), + .recv_flood_size = nReceiveFloodSize, + .use_v2transport = use_v2transport, + }); + pnode->AddRef(); - NetPermissionFlags permission_flags = NetPermissionFlags::None; - std::vector<NetWhitelistPermissions> whitelist_permissions = conn_type == ConnectionType::MANUAL ? vWhitelistedRangeOutgoing : std::vector<NetWhitelistPermissions>{}; - AddWhitelistPermissionFlags(permission_flags, addrConnect, whitelist_permissions); + // We're making a new connection, harvest entropy from the time (and our peer count) + RandAddEvent((uint32_t)id); - // Add node - NodeId id = GetNewNodeId(); - uint64_t nonce = GetDeterministicRandomizer(RANDOMIZER_ID_LOCALHOSTNONCE).Write(id).Finalize(); - if (!addr_bind.IsValid()) { - addr_bind = GetBindAddress(*sock); + return pnode; } - CNode* pnode = new CNode(id, - std::move(sock), - addrConnect, - CalculateKeyedNetGroup(addrConnect), - nonce, - addr_bind, - pszDest ? pszDest : "", - conn_type, - /*inbound_onion=*/false, - CNodeOptions{ - .permission_flags = permission_flags, - .i2p_sam_session = std::move(i2p_transient_session), - .recv_flood_size = nReceiveFloodSize, - .use_v2transport = use_v2transport, - }); - pnode->AddRef(); - - // We're making a new connection, harvest entropy from the time (and our peer count) - RandAddEvent((uint32_t)id); - return pnode; + return nullptr; } void CNode::CloseSocketDisconnect() @@ -2256,7 +2272,11 @@ void CConnman::ThreadDNSAddressSeed() if (!resolveSource.SetInternal(host)) { continue; } - unsigned int nMaxIPs = 256; // Limits number of IPs learned from a DNS seed + // Limit number of IPs learned from a single DNS seed. This limit exists to prevent the results from + // one DNS seed from dominating AddrMan. Note that the number of results from a UDP DNS query is + // bounded to 33 already, but it is possible for it to use TCP where a larger number of results can be + // returned. + unsigned int nMaxIPs = 32; const auto addresses{LookupHost(host, nMaxIPs, true)}; if (!addresses.empty()) { for (const CNetAddr& ip : addresses) { |