diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/net.cpp | 20 | ||||
| -rw-r--r-- | src/net.h | 12 | ||||
| -rw-r--r-- | src/net_processing.cpp | 2 |
3 files changed, 23 insertions, 11 deletions
diff --git a/src/net.cpp b/src/net.cpp index 7841965f60..e43b480612 100644 --- a/src/net.cpp +++ b/src/net.cpp @@ -94,6 +94,7 @@ const std::string NET_MESSAGE_COMMAND_OTHER = "*other*"; static const uint64_t RANDOMIZER_ID_NETGROUP = 0x6c0edd8036ef4036ULL; // SHA256("netgroup")[0:8] static const uint64_t RANDOMIZER_ID_LOCALHOSTNONCE = 0xd93e69e2bbfa5735ULL; // SHA256("localhostnonce")[0:8] +static const uint64_t RANDOMIZER_ID_ADDRCACHE = 0x1cf2e4ddd306dda9ULL; // SHA256("addrcache")[0:8] // // Global state variables // @@ -2539,12 +2540,19 @@ std::vector<CAddress> CConnman::GetAddresses(size_t max_addresses, size_t max_pc return addresses; } -std::vector<CAddress> CConnman::GetAddresses(Network requestor_network, size_t max_addresses, size_t max_pct) +std::vector<CAddress> CConnman::GetAddresses(CNode& requestor, size_t max_addresses, size_t max_pct) { + SOCKET socket; + WITH_LOCK(requestor.cs_hSocket, socket = requestor.hSocket); + auto local_socket_bytes = GetBindAddress(socket).GetAddrBytes(); + uint64_t cache_id = GetDeterministicRandomizer(RANDOMIZER_ID_ADDRCACHE) + .Write(requestor.addr.GetNetwork()) + .Write(local_socket_bytes.data(), local_socket_bytes.size()) + .Finalize(); const auto current_time = GetTime<std::chrono::microseconds>(); - if (m_addr_response_caches.find(requestor_network) == m_addr_response_caches.end() || - m_addr_response_caches[requestor_network].m_update_addr_response < current_time) { - m_addr_response_caches[requestor_network].m_addrs_response_cache = GetAddresses(max_addresses, max_pct); + if (m_addr_response_caches.find(cache_id) == m_addr_response_caches.end() || + m_addr_response_caches[cache_id].m_update_addr_response < current_time) { + m_addr_response_caches[cache_id].m_addrs_response_cache = GetAddresses(max_addresses, max_pct); // Choosing a proper cache lifetime is a trade-off between the privacy leak minimization // and the usefulness of ADDR responses to honest users. @@ -2570,9 +2578,9 @@ std::vector<CAddress> CConnman::GetAddresses(Network requestor_network, size_t m // nodes to be "terrible" (see IsTerrible()) if the timestamps are older than 30 days, // max. 24 hours of "penalty" due to cache shouldn't make any meaningful difference // in terms of the freshness of the response. - m_addr_response_caches[requestor_network].m_update_addr_response = current_time + std::chrono::hours(21) + GetRandMillis(std::chrono::hours(6)); + m_addr_response_caches[cache_id].m_update_addr_response = current_time + std::chrono::hours(21) + GetRandMillis(std::chrono::hours(6)); } - return m_addr_response_caches[requestor_network].m_addrs_response_cache; + return m_addr_response_caches[cache_id].m_addrs_response_cache; } bool CConnman::AddNode(const std::string& strNode) @@ -269,7 +269,7 @@ public: * A non-malicious call (from RPC or a peer with addr permission) should * call the function without a parameter to avoid using the cache. */ - std::vector<CAddress> GetAddresses(Network requestor_network, size_t max_addresses, size_t max_pct); + std::vector<CAddress> GetAddresses(CNode& requestor, size_t max_addresses, size_t max_pct); // This allows temporarily exceeding m_max_outbound_full_relay, with the goal of finding // a peer that is better than all our current peers. @@ -447,15 +447,19 @@ private: /** * Addr responses stored in different caches - * per network prevent cross-network node identification. + * per (network, local socket) prevent cross-network node identification. * If a node for example is multi-homed under Tor and IPv6, * a single cache (or no cache at all) would let an attacker * to easily detect that it is the same node by comparing responses. + * Indexing by local socket prevents leakage when a node has multiple + * listening addresses on the same network. + * * The used memory equals to 1000 CAddress records (or around 32 bytes) per * distinct Network (up to 5) we have/had an inbound peer from, - * resulting in at most ~160 KB. + * resulting in at most ~160 KB. Every separate local socket may + * add up to ~160 KB extra. */ - std::map<Network, CachedAddrResponse> m_addr_response_caches; + std::map<uint64_t, CachedAddrResponse> m_addr_response_caches; /** * Services this instance offers. diff --git a/src/net_processing.cpp b/src/net_processing.cpp index 60bdfbe9f5..bf359a0d68 100644 --- a/src/net_processing.cpp +++ b/src/net_processing.cpp @@ -3516,7 +3516,7 @@ void PeerLogicValidation::ProcessMessage(CNode& pfrom, const std::string& msg_ty if (pfrom.HasPermission(PF_ADDR)) { vAddr = m_connman.GetAddresses(MAX_ADDR_TO_SEND, MAX_PCT_ADDR_TO_SEND); } else { - vAddr = m_connman.GetAddresses(pfrom.addr.GetNetwork(), MAX_ADDR_TO_SEND, MAX_PCT_ADDR_TO_SEND); + vAddr = m_connman.GetAddresses(pfrom, MAX_ADDR_TO_SEND, MAX_PCT_ADDR_TO_SEND); } FastRandomContext insecure_rand; for (const CAddress &addr : vAddr) { |