diff options
| -rw-r--r-- | src/net.cpp | 16 | ||||
| -rw-r--r-- | src/net.h | 11 | ||||
| -rw-r--r-- | src/net_processing.cpp | 23 | ||||
| -rw-r--r-- | src/validation.h | 14 |
4 files changed, 45 insertions, 19 deletions
diff --git a/src/net.cpp b/src/net.cpp index 55043ffe30..12bdcb465a 100644 --- a/src/net.cpp +++ b/src/net.cpp @@ -2864,8 +2864,20 @@ bool CConnman::ForNode(NodeId id, std::function<bool(CNode* pnode)> func) return found != nullptr && NodeFullyConnected(found) && func(found); } -int64_t PoissonNextSend(int64_t nNow, int average_interval_seconds) { - return nNow + (int64_t)(log1p(GetRand(1ULL << 48) * -0.0000000000000035527136788 /* -1/2^48 */) * average_interval_seconds * -1000000.0 + 0.5); +int64_t CConnman::PoissonNextSendInbound(int64_t now, int average_interval_seconds) +{ + if (m_next_send_inv_to_incoming < now) { + // If this function were called from multiple threads simultaneously + // it would possible that both update the next send variable, and return a different result to their caller. + // This is not possible in practice as only the net processing thread invokes this function. + m_next_send_inv_to_incoming = PoissonNextSend(now, average_interval_seconds); + } + return m_next_send_inv_to_incoming; +} + +int64_t PoissonNextSend(int64_t now, int average_interval_seconds) +{ + return now + (int64_t)(log1p(GetRand(1ULL << 48) * -0.0000000000000035527136788 /* -1/2^48 */) * average_interval_seconds * -1000000.0 + 0.5); } CSipHasher CConnman::GetDeterministicRandomizer(uint64_t id) const @@ -310,6 +310,13 @@ public: unsigned int GetReceiveFloodSize() const; void WakeMessageHandler(); + + /** Attempts to obfuscate tx time through exponentially distributed emitting. + Works assuming that a single interval is used. + Variable intervals will result in privacy decrease. + */ + int64_t PoissonNextSendInbound(int64_t now, int average_interval_seconds); + private: struct ListenSocket { SOCKET socket; @@ -434,6 +441,8 @@ private: * This takes the place of a feeler connection */ std::atomic_bool m_try_another_outbound_peer; + std::atomic<int64_t> m_next_send_inv_to_incoming; + friend struct CConnmanTest; }; extern std::unique_ptr<CConnman> g_connman; @@ -863,6 +872,6 @@ public: /** Return a timestamp in the future (in microseconds) for exponentially distributed events. */ -int64_t PoissonNextSend(int64_t nNow, int average_interval_seconds); +int64_t PoissonNextSend(int64_t now, int average_interval_seconds); #endif // BITCOIN_NET_H diff --git a/src/net_processing.cpp b/src/net_processing.cpp index ed9debc95a..473a4b8c55 100644 --- a/src/net_processing.cpp +++ b/src/net_processing.cpp @@ -71,6 +71,21 @@ static const int STALE_RELAY_AGE_LIMIT = 30 * 24 * 60 * 60; /// limiting block relay. Set to one week, denominated in seconds. static const int HISTORICAL_BLOCK_AGE = 7 * 24 * 60 * 60; +/** Average delay between local address broadcasts in seconds. */ +static constexpr unsigned int AVG_LOCAL_ADDRESS_BROADCAST_INTERVAL = 24 * 60 * 60; +/** Average delay between peer address broadcasts in seconds. */ +static const unsigned int AVG_ADDRESS_BROADCAST_INTERVAL = 30; +/** Average delay between trickled inventory transmissions in seconds. + * Blocks and whitelisted receivers bypass this, outbound peers get half this delay. */ +static const unsigned int INVENTORY_BROADCAST_INTERVAL = 5; +/** Maximum number of inventory items to send per transmission. + * Limits the impact of low-fee transaction floods. */ +static constexpr unsigned int INVENTORY_BROADCAST_MAX = 7 * INVENTORY_BROADCAST_INTERVAL; +/** Average delay between feefilter broadcasts in seconds. */ +static constexpr unsigned int AVG_FEEFILTER_BROADCAST_INTERVAL = 10 * 60; +/** Maximum feefilter broadcast delay after significant change. */ +static constexpr unsigned int MAX_FEEFILTER_CHANGE_DELAY = 5 * 60; + // Internal stuff namespace { /** Number of nodes with fSyncStarted. */ @@ -3496,8 +3511,12 @@ bool PeerLogicValidation::SendMessages(CNode* pto, std::atomic<bool>& interruptM bool fSendTrickle = pto->fWhitelisted; if (pto->nNextInvSend < nNow) { fSendTrickle = true; - // Use half the delay for outbound peers, as there is less privacy concern for them. - pto->nNextInvSend = PoissonNextSend(nNow, INVENTORY_BROADCAST_INTERVAL >> !pto->fInbound); + if (pto->fInbound) { + pto->nNextInvSend = connman->PoissonNextSendInbound(nNow, INVENTORY_BROADCAST_INTERVAL); + } else { + // Use half the delay for outbound peers, as there is less privacy concern for them. + pto->nNextInvSend = PoissonNextSend(nNow, INVENTORY_BROADCAST_INTERVAL >> 1); + } } // Time to send but the peer has requested we not relay transactions. diff --git a/src/validation.h b/src/validation.h index b9c2f6c023..cd29083f21 100644 --- a/src/validation.h +++ b/src/validation.h @@ -104,20 +104,6 @@ static const unsigned int DATABASE_WRITE_INTERVAL = 60 * 60; static const unsigned int DATABASE_FLUSH_INTERVAL = 24 * 60 * 60; /** Maximum length of reject messages. */ static const unsigned int MAX_REJECT_MESSAGE_LENGTH = 111; -/** Average delay between local address broadcasts in seconds. */ -static const unsigned int AVG_LOCAL_ADDRESS_BROADCAST_INTERVAL = 24 * 60 * 60; -/** Average delay between peer address broadcasts in seconds. */ -static const unsigned int AVG_ADDRESS_BROADCAST_INTERVAL = 30; -/** Average delay between trickled inventory transmissions in seconds. - * Blocks and whitelisted receivers bypass this, outbound peers get half this delay. */ -static const unsigned int INVENTORY_BROADCAST_INTERVAL = 5; -/** Maximum number of inventory items to send per transmission. - * Limits the impact of low-fee transaction floods. */ -static const unsigned int INVENTORY_BROADCAST_MAX = 7 * INVENTORY_BROADCAST_INTERVAL; -/** Average delay between feefilter broadcasts in seconds. */ -static const unsigned int AVG_FEEFILTER_BROADCAST_INTERVAL = 10 * 60; -/** Maximum feefilter broadcast delay after significant change. */ -static const unsigned int MAX_FEEFILTER_CHANGE_DELAY = 5 * 60; /** Block download timeout base, expressed in millionths of the block interval (i.e. 10 min) */ static const int64_t BLOCK_DOWNLOAD_TIMEOUT_BASE = 1000000; /** Additional block download timeout per parallel downloading peer (i.e. 5 min) */ |